Detailed Description
[ Optical film ]
An optical film according to an embodiment will be described below. The optical film according to the present embodiment (hereinafter, also simply referred to as "optical film") contains a compound (a) (hereinafter, also simply referred to as "compound (a)") having a skeleton represented by the following formula (A1) as a partial structure, and the content of the compound (a) per unit volume is 2.5kg/m3 to 30kg/m3.
[ Chemical formula 2]
The optical film contains the compound (a) and the content thereof is in the above numerical range, whereby the wavelength dispersion value is not easily changed even in the case of exposure to light.
The skeleton represented by the formula (A1) is a skeleton formed of carbon atoms and sulfur atoms, which is included in the compound represented by the formula (A1).
In view of the tendency that the optical film is less likely to change in wavelength dispersion value and phase difference value even when exposed to light, the compound (a) contained in the optical film preferably has a substituent represented by the following general formula (a 11). From the same viewpoint, the number of the substituents is preferably 1 or 2, more preferably 2.
[ Chemical formula 3]
In formula (A11), the alternative represents a linkage.
In the formula (A11), R11 represents a hydrocarbon group. The number of carbon atoms of the hydrocarbon group may be, for example, 1 to 20.
The compound (a) contained in the optical film is preferably a compound having a group represented by any one of the following formulas (a 21) and (a 22) in view of the tendency that the optical film becomes an optical film which is less likely to change in wavelength dispersion value and phase difference value even when exposed to light, and more preferably a compound having a group represented by the following formula (a 21) in view of the tendency that the optical film becomes an optical film which is less likely to change in phase difference value even when exposed to light. In formula (a 21) and (a 22)), the connection bond is represented.
[ Chemical formula 4]
The compound (a) is preferably a compound represented by the following formulas (a 31) to (a 36) and a compound derived from the following formulas (a 31) and (a 32) in view of the tendency of the optical film to be an optical film which is less likely to change in wavelength dispersion value and phase difference value even when exposed to light, and is more preferably a compound represented by the following formula (a 31) and a compound derived from the following formula (a 31) in view of the tendency of the optical film to be an optical film which is less likely to change in phase difference value even when exposed to light.
[ Chemical formula 5]
In view of the tendency that the optical film is less likely to change in wavelength dispersion value and phase difference value even when exposed to light, the CLogP of the compound (a) contained in the optical film is preferably 2 to 10, more preferably 4 to 9.CLogP is a value for estimating the affinity of an organic compound for water and 1-octanol [ p= (concentration of an organic compound in 1-octanol phase)/(concentration of an organic compound in aqueous phase) ], and can be calculated by a calculation program using a fragment value of an atomic group determined by the number of atoms constituting the compound and the type of chemical bond. In this specification, CLogP refers to a value calculated using Chem draw.18.2 of PerkinElmer corporation.
The content of the compound (A) per unit volume of the optical film is 2.5kg/m3 or more. The content is preferably 3kg/m3 or more, from the viewpoint that the optical film tends to be less likely to change in wavelength dispersion value and phase difference value even when exposed to light. The content of the compound (A) per unit volume of the optical film is 30kg/m3 or less. The content is preferably 29kg/m3 or less, from the viewpoint that the optical film tends to be less likely to change in wavelength dispersion value and phase difference value even when exposed to light.
The optical film preferably contains at least one of a cured product and an uncured product of a polymerizable liquid crystal compound in addition to the compound (a). The optical film may be a cured product of a polymerizable liquid crystal composition containing a polymerizable liquid crystal compound and the compound (a). The compound (a) may have functions of, for example, a leveling agent, an antioxidant, a polymerization initiator, and a colorant in the polymerizable liquid crystal composition.
The content of the cured product of the polymerizable liquid crystal compound may be 70 mass% or more, 80 mass% or more, 90 mass% or more, or 95 mass% or more based on the total amount of the optical film.
In the present specification, the polymerizable liquid crystal compound means a liquid crystal compound having a polymerizable group, particularly a photopolymerizable group. As the polymerizable liquid crystal compound, for example, a polymerizable liquid crystal compound conventionally known in the field of a retardation film can be used.
The polymerizable group means a group capable of participating in polymerization. The photopolymerizable group is a group that can participate in polymerization reaction by using reactive species generated by a photopolymerization initiator, for example, a living radical, an acid, or the like, as a polymerizable group. Examples of the photopolymerizable group include vinyl, vinyloxy, 1-chlorovinyl, isopropenyl, 4-vinylphenyl, acryloyloxy, methacryloyloxy, oxetanyl and oxetanyl groups. Among them, acryloyloxy, methacryloyloxy, vinyloxy, oxetanyl and oxetanyl groups are preferable, and acryloyloxy is more preferable. The liquid crystal property exhibited by the polymerizable liquid crystal compound may be a thermotropic liquid crystal or a lyotropic liquid crystal, and is preferably a thermotropic liquid crystal in view of enabling precise film thickness control. The phase-ordered structure in the thermotropic liquid crystal may be a nematic liquid crystal or a smectic liquid crystal. The polymerizable liquid crystal compound may be used singly or in combination of two or more.
The polymerizable liquid crystal compound is preferably a compound having the following characteristics (1) to (4).
(1) Is a compound capable of forming a nematic or smectic phase.
(2) The polymerizable liquid crystal compound has pi electrons in the long axis direction (a).
(3) Pi electrons are present in a direction intersecting the long axis direction (a) [ intersecting direction (b) ].
(4) The pi electron density in the long axis direction (a) of the polymerizable liquid crystal compound defined by the following formula (i) by taking the total of pi electrons present in the long axis direction (a) as N (pi a) and the total of molecular weights present in the long axis direction as N (Aa):
D (pi a) =n (pi a)/N (Aa) (i), and,
The pi electron density in the cross direction (b) of the polymerizable liquid crystal compound defined by the following formula (ii) by taking the sum of pi electrons present in the cross direction (b) as N (pi b) and the sum of molecular weights present in the cross direction (b) as N (Ab):
D(πb)=N(πb)/N(Ab)(ii)
there is a relationship of formula (iii):
0≤〔D(πa)/D(πb)〕<1(iii)
[ i.e., the pi electron density in the cross direction (b) is greater than the pi electron density in the long axis direction (a) ]. As described above, the polymerizable liquid crystal compound having pi electrons in the long axis and the direction intersecting the long axis has, for example, a T-shaped structure.
The polymerizable liquid crystal compound is preferably a compound capable of forming a nematic phase.
In the features (1) to (4), the long axis direction (a) and pi-electron number N are defined as follows.
For example, in the case of a compound having a rod-like structure, the long axis direction (a) is the long axis direction of the rod.
Pi electrons that disappear due to the polymerization reaction are not included in pi electron number N (pi a) existing in the long axis direction (a).
The pi electrons N (pi a) existing in the long axis direction (a) include the number of pi electrons existing in the ring which is the sum of pi electrons on the long axis and pi electrons conjugated thereto, for example, existing in the long axis direction (a) and satisfies the rule of the shock.
Pi electrons that disappear due to the polymerization reaction are not included in the pi electron number N (pi b) existing in the cross direction (b).
The polymerizable liquid crystal compound satisfying the above characteristics has a mesogenic structure in the long axis direction. The mesogenic structure exhibits a liquid crystal phase (nematic phase, smectic phase).
The polymerizable liquid crystal compounds satisfying the above (1) to (4) can be applied to a photo-alignment film described later and heated to a temperature equal to or higher than the phase transition temperature, thereby forming a nematic phase and a smectic phase. In a nematic phase or smectic phase formed by aligning the polymerizable liquid crystal compound, for example, alignment is performed such that the long axis directions of the polymerizable liquid crystal compound are parallel to each other, and the long axis directions are alignment directions of the nematic phase. When such a polymerizable liquid crystal compound is formed into a film and polymerized in a nematic phase or smectic phase, a polymer film formed of a polymer obtained by polymerization in a state of being oriented in the long axis direction (a) can be formed. The polymer film absorbs ultraviolet rays by pi electrons in the long axis direction (a) and pi electrons in the cross direction (b).
Here, the maximum absorption wavelength of ultraviolet light absorbed by pi electrons in the cross direction (b) is set to λbmax. The λbmax is usually 300nm to 400nm. Since pi electron density satisfies the above formula (iii), pi electron density in the cross direction (b) is larger than pi electron density in the long axis direction (a), it is a polymer film having higher absorption of linearly polarized ultraviolet light (wavelength λbmax) having a vibration plane in the cross direction (b) than that of linearly polarized ultraviolet light (wavelength λbmax) having a vibration plane in the long axis direction (a). The ratio (ratio of absorbance in the cross direction (b) of linearly polarized ultraviolet rays to absorbance in the longitudinal direction (a)) is, for example, greater than 1.0, preferably 1.2 or more and 30 or less, for example, 10 or less.
The polymerizable liquid crystal compound having the above-mentioned characteristics is usually a compound exhibiting inverse wavelength dispersibility in many cases. Specifically, for example, a compound represented by the following formula (X) is given.
[ Chemical formula 6]
In the formula (X), ar represents a divalent aromatic group which may have a substituent. Here, the aromatic group means a group containing an aromatic ring having pi electrons of the ring structure [4n+2] numbers according to the scholler rule. Here, n represents an integer. When a ring structure is formed so as to contain heteroatoms such as-n=, -S-, and the like, the case where the aromatic character is satisfied by including a pair of noncovalent electrons on these heteroatoms, is also included. The aromatic group preferably contains at least 1 or more of a nitrogen atom, an oxygen atom and a sulfur atom. The number of aromatic rings contained in Ar may be 1 or 2 or more. When the number of aromatic rings included in Ar is 2 or more, 2 or more aromatic rings may be bonded to each other through a divalent bonding group such as a single bond, -CO-O-, -O-.
G1 and G2 each independently represent a divalent aromatic group or a divalent alicyclic hydrocarbon group. The hydrogen atom contained in the divalent aromatic group or the divalent alicyclic hydrocarbon group may be substituted with a halogen atom, an alkyl group having 1 to 4 carbon atoms, a fluoroalkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a cyano group or a nitro group, and the carbon atoms constituting the divalent aromatic group or the divalent alicyclic hydrocarbon group may be substituted with an oxygen atom, a sulfur atom or a nitrogen atom.
Each of G1 and G2 is independently preferably a1, 4-phenylenediyl group which may be substituted with at least 1 substituent selected from the group consisting of a halogen atom and an alkyl group having 1 to 4 carbon atoms, or a1, 4-cyclohexanediyl group which may be substituted with at least 1 substituent selected from the group consisting of a halogen atom and an alkyl group having 1 to 4 carbon atoms, more preferably a1, 4-phenylenediyl group substituted with a methyl group, an unsubstituted 1, 4-phenylenediyl group or an unsubstituted 1, 4-trans-cyclohexanediyl group, further preferably an unsubstituted 1, 4-phenylenediyl group or an unsubstituted 1, 4-trans-cyclohexanediyl group.
It is preferable that at least 1 of G1 and G2 in the plurality of groups is a divalent alicyclic hydrocarbon group, and it is more preferable that at least 1 of G1 and G2 bonded to L1 or L2 is a divalent alicyclic hydrocarbon group.
L1、L2、B1 and B2 are each independently a single bond or a divalent linking group.
L1 and L2 are each independently preferably a single bond, an alkylene group 、-O-、-S-、-Ra1ORa2-、-Ra3COORa4-、-Ra5OCORa6-、Ra7OC＝OORa8-、-N＝N-、-CRc＝CRd- having 1 to 4 carbon atoms or-C.ident.C-. Here, Ra1～Ra8 each independently represents a single bond or an alkylene group having 1 to 4 carbon atoms, and Rc and Rd each represent an alkyl group having 1 to 4 carbon atoms or a hydrogen atom. L1 and L2 are each independently more preferably a single bond, -ORa2-1-、-CH2-、-CH2CH2-、-COORa4-1 -, OR OCORa6-1 -. Here, Ra2-1、Ra4-1 and Ra6-1 each independently represent any one of a single bond, -CH2 -and-CH2CH2 -. L1 and L2 are each independently further preferably a single bond, -O-, -CH2CH2-、-COO-、-COOCH2CH2 -, or OCO-.
B1 and B2 are each independently preferably a single bond, an alkylene group having 1 to 4 carbon atoms, -O-, -S-, -Ra9ORa10-、-Ra11COORa12-、-Ra13OCORa14 -or Ra15OC＝OORa16-.Ra9～Ra16 is each independently a single bond or an alkylene group having 1 to 4 carbon atoms. B1 and B2 are each independently more preferably a single bond, -ORa10-1-、-CH2-、-CH2CH2-、-COORa12-1 -, OR OCORa14-1 -. Here, Ra10-1、Ra12-1 and Ra14-1 each independently represent any one of a single bond, -CH2 -, and-CH2CH2 -. B1 and B2 are each independently further preferably a single bond, -O-, -CH2CH2-、-COO-、-COOCH2CH2 -, -OCO-or OCOCH2CH2 -.
K. l each independently represents an integer of 0 to 3, and satisfies a relationship of 1.ltoreq.k+l. Here, when 2.ltoreq.k+l, B1、B2、G1 and G2 each may be the same or different from each other.
From the viewpoint of exhibiting inverse wavelength dispersibility, k and l are preferably in the range of 2.ltoreq.k+l.ltoreq.6, k+l=4 is preferred, k=2 is more preferred, and l=2 is preferred. k=2 and l=2 in a symmetrical structure, therefore, it is preferable.
E1 and E2 each independently represent an alkanediyl group having 1 to 17 carbon atoms. E1 and E2 are more preferably alkanediyl having 4 to 12 carbon atoms. In addition, the hydrogen atom contained in the alkanediyl group may be substituted by a halogen atom, the alkanediyl group comprises-CH2 -which may be replaced by-O-, -S-, -SiH2 -or-C (=o) -substitution.
P1 and P2 each independently represent a polymerizable group or a hydrogen atom, and at least 1 is a polymerizable group.
Examples of the polymerizable group represented by P1 or P2 include an epoxy group, a vinyl group, a vinyloxy group, a 1-chlorovinyl group, an isopropenyl group, a 4-vinylphenyl group, an acryloyloxy group, a methacryloyloxy group, an oxetanyl group, and an oxetanyl group. Among them, acryloyloxy, methacryloyloxy, vinyloxy, oxetanyl and oxetanyl groups are preferable, and acryloyloxy is more preferable.
Ar preferably has at least one selected from the group consisting of an aromatic hydrocarbon ring which may have a substituent, an aromatic heterocyclic ring which may have a substituent, and an electron withdrawing group. Examples of the aromatic hydrocarbon ring include a benzene ring, a naphthalene ring, and an anthracene ring, and a benzene ring and a naphthalene ring are preferable. Examples of the aromatic heterocycle include a furan ring, a benzofuran ring, a pyrrole ring, an indole ring, a thiophene ring, a benzothiophene ring, a pyridine ring, a pyrazine ring, a pyrimidine ring, a triazole ring, a triazine ring, a pyrroline ring, an imidazole ring, a pyrazole ring, a thiazole ring, a benzothiazole ring, a thienothiazole ring, an oxazole ring, a benzoxazole ring, and a phenanthroline ring. Among them, a thiazole ring, a benzothiazole ring or a benzofuran ring is preferable, and a benzothiazolyl group is more preferable. In addition, in the case where a nitrogen atom is contained in Ar, the nitrogen atom preferably has pi electrons.
In the formula (X), the total number N pi of pi electrons included in the 2-valent aromatic group represented by Ar is preferably 8 or more, more preferably 10 or more, further preferably 14 or more, and particularly preferably 16 or more. The content is preferably 30 or less, more preferably 26 or less, and even more preferably 24 or less.
Examples of the aromatic group represented by Ar include the following groups.
[ Chemical formula 7]
In the formula (Ar-1) to (Ar-23), the symbols represent a bond, and Z0、Z1 and Z2 each independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 12 carbon atoms, a cyano group, a nitro group, an alkylsulfinyl group having 1 to 12 carbon atoms, an alkylsulfonyl group having 1 to 12 carbon atoms, a carboxyl group, a fluoroalkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkylthio group having 1 to 12 carbon atoms, an N-alkylamino group having 1 to 12 carbon atoms, an N, N-dialkylamino group having 2 to 12 carbon atoms, an N-alkylsulfonyl group having 1 to 12 carbon atoms, or an N, N-dialkylsulfamoyl group having 2 to 12 carbon atoms. In addition, Z0、Z1 and Z2 may contain a polymerizable group.
Q1 and Q2 each independently represent-CR21R22-、-S-、-NH-、-NR21 -; -CO-or-O-, R21 and R22 each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.
Q1 and Q2 are preferably-NH-, -S-, -NR21 -and-O-. R21 is preferably a hydrogen atom. Q1 and Q2 are more preferably-S-, -O-and-NH-.
J1 and J2 each independently represent a carbon atom or a nitrogen atom.
Y1、Y2 and Y3 each independently represent an aromatic hydrocarbon group or an aromatic heterocyclic group which may be substituted.
W1 and W2 each independently represent a hydrogen atom, a cyano group, a methyl group or a halogen atom, and m represents an integer of 0 to 6.
Examples of the aromatic hydrocarbon group in Y1、Y2 and Y3 include aromatic hydrocarbon groups having 6 to 20 carbon atoms such as phenyl, naphthyl, anthryl, phenanthryl and biphenyl, and are preferably phenyl and naphthyl, and more preferably phenyl. Examples of the aromatic heterocyclic group include an aromatic heterocyclic group having 4 to 20 carbon atoms, which contains at least 1 heteroatom such as a nitrogen atom, an oxygen atom, and a sulfur atom, such as a furyl group, a pyrrolyl group, a thienyl group, a pyridyl group, a thiazolyl group, and a benzothiazolyl group, and preferable examples thereof are a furyl group, a thienyl group, a pyridyl group, a thiazolyl group, and a benzothiazolyl group.
Y1、Y2 and Y3 each independently may be an optionally substituted polycyclic aromatic hydrocarbon group or a polycyclic aromatic heterocyclic group. Polycyclic aromatic hydrocarbon group refers to a condensed polycyclic aromatic hydrocarbon group or a group derived from an aromatic ring set. Polycyclic aromatic heterocyclic groups refer to fused polycyclic aromatic heterocyclic groups or groups from an aromatic ring set.
Z0、Z1 and Z2 are each independently preferably a hydrogen atom, a halogen atom, an alkyl group having 1 to 12 carbon atoms, a cyano group, a nitro group, or an alkoxy group having 1 to 12 carbon atoms, Z0 is more preferably a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, a cyano group, and Z1 and Z2 are more preferably a hydrogen atom, a fluorine atom, a chlorine atom, a methyl group, or a cyano group. Z0、Z1 and Z2 may also contain polymerizable groups.
Of the formulae (Ar-1) to (Ar-23), the formulae (Ar-6) and (Ar-7) are preferable from the viewpoint of molecular stability.
In the formulae (Ar-16) to (Ar-23), Y1 may form an aromatic heterocyclic group together with the nitrogen atom to which it is bonded and Z0. Examples of the aromatic heterocyclic group include the rings described above as aromatic heterocyclic groups that Ar may have, and examples thereof include pyrrole rings, imidazole rings, pyrroline rings, pyridine rings, pyrazine rings, pyrimidine rings, indole rings, quinoline rings, isoquinoline rings, purine rings, and pyrrolidine rings. The aromatic heterocyclic group may have a substituent. Further, Y1 may be the above-mentioned optionally substituted polycyclic aromatic hydrocarbon group or polycyclic aromatic heterocyclic group together with the nitrogen atom to which it is bonded and Z0. For example, a benzofuran ring, a benzothiazole ring, and a benzoxazole ring can be cited.
The content of the polymerizable liquid crystal compound in the polymerizable liquid crystal composition is, for example, 70 to 99.5 parts by mass, preferably 80 to 99 parts by mass, more preferably 85 to 98 parts by mass, and even more preferably 90 to 95 parts by mass, per 100 parts by mass of the solid content of the polymerizable liquid crystal composition. When the content of the polymerizable liquid crystal compound is within the above range, it is advantageous from the viewpoint of the orientation of the obtained liquid crystal cured film. In the present specification, the solid content of the polymerizable liquid crystal composition refers to all components from which volatile components such as an organic solvent are removed from the polymerizable liquid crystal composition.
The polymerizable liquid crystal composition contains a compound (A). The content of the compound (a) in the polymerizable liquid crystal composition is, for example, 1 to 20 parts by mass, preferably 3 to 12 parts by mass, and more preferably 5 to 10 parts by mass, per 100 parts by mass of the solid content of the polymerizable liquid crystal composition, in view of the tendency that the optical film becomes an optical film which is less liable to change in the wavelength dispersion value and the phase difference value even when exposed to light.
The polymerizable liquid crystal composition may contain additives such as a solvent, a photopolymerization initiator, a leveling agent, an antioxidant, and a photosensitizing agent in addition to the polymerizable liquid crystal compound and the compound (a). These components may be used alone in 1 kind, or may be used in combination of 2 or more kinds.
The polymerizable liquid crystal composition is usually applied to a substrate or the like in a state of being dissolved in a solvent, and therefore, preferably contains a solvent. The solvent is preferably a solvent capable of dissolving the polymerizable liquid crystal compound, and is preferably a solvent inactive to the polymerization reaction of the polymerizable liquid crystal compound. Examples of the solvent include alcohol solvents such as water, methanol, ethanol, ethylene glycol, isopropanol, propylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether, 1-methoxy-2-propanol, 2-butoxyethanol, and propylene glycol monomethyl ether, ester solvents such as ethyl acetate, butyl acetate, ethylene glycol methyl ether acetate, γ -butyrolactone, propylene glycol methyl ether acetate, and ethyl lactate, ketone solvents such as acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-heptanone, and methyl isobutyl ketone, aliphatic hydrocarbon solvents such as pentane, hexane, and heptane, alicyclic hydrocarbon solvents such as ethylcyclohexane, aromatic hydrocarbon solvents such as toluene and xylene, nitrile solvents such as acetonitrile, ether solvents such as tetrahydrofuran and dimethoxyethane, chlorine-containing solvents such as chloroform and chlorobenzene, amide solvents such as dimethylacetamide, dimethylformamide, N-methyl-2-pyrrolidone (NMP), and 1, 3-dimethyl-2-imidazolidinone, and the like. These solvents may be used singly or in combination of two or more. Among them, alcohol solvents, ester solvents, ketone solvents, chlorine-containing solvents, amide solvents, and aromatic hydrocarbon solvents are preferable.
The content of the solvent in the polymerizable liquid crystal composition is preferably 50 to 98 parts by mass, more preferably 70 to 95 parts by mass, relative to 100 parts by mass of the polymerizable liquid crystal composition. Therefore, the solid content is preferably 2 to 50 parts by mass based on 100 parts by mass of the polymerizable liquid crystal composition. When the solid content is 50 parts by mass or less, the viscosity of the polymerizable liquid crystal composition becomes low, and thus the film thickness becomes substantially uniform, and unevenness tends to be less likely to occur. The solid content can be appropriately determined in consideration of the thickness of the liquid crystal cured film to be produced.
The polymerization initiator is a compound which generates a reactive species by the action of heat or light and can initiate the polymerization reaction of a polymerizable liquid crystal compound or the like. Examples of the reactive species include free radicals, active species such as cations and anions. Among them, a photopolymerization initiator that generates radicals by light irradiation is preferable from the viewpoint of easy control of the reaction.
Examples of the photopolymerization initiator include benzoin compounds, benzophenone compounds, benzil ketal compounds, oxime compounds, α -hydroxyketone compounds, α -aminoketone compounds, triazine compounds, iodonium salts, and sulfonium salts.
The content of the photopolymerization initiator is, for example, 0.1 to 30 parts by mass, preferably 1 to 20 parts by mass, and more preferably 1 to 15 parts by mass, based on 100 parts by mass of the polymerizable liquid crystal compound. If the amount is within the above range, the reaction of the polymerizable group proceeds sufficiently, and the alignment of the polymerizable liquid crystal compound is not easily disturbed.
The leveling agent is an additive having a function of adjusting the fluidity of the polymerizable liquid crystal composition and flattening a coating film obtained by applying the composition, and examples thereof include silicone-based, polyacrylate-based, and perfluoroalkyl-based leveling agents. As the leveling agent, commercially available products, specifically, examples thereof include DC3PA, SH7PA, DC11PA, SH28PA, SH29PA, SH30PA, ST80PA, ST86PA, SH8400, SH8700, FZ2123 (manufactured by Touretonin Co., ltd., all of them), KP321, KP323, KP324, KP326, KP340, KP341, X22-161A, KF6001 (manufactured by Xinyue chemical industry Co., ltd., all of them), TSF400, TSF401, TSF410, TSF4300, TSF4440, TSF4445, TSF-4446, TSF4452, TSF4460 (manufactured by Migao Japan contract Co., all of them), fluorine resin FC-72, fluorine resin FC-40, fluorine resin FC-43 Florinerert FC-3283 (manufactured by Surflon 3M (Inc.), MEGAFACE (manufactured by DIC (Inc.) of registered trademark )R-08、MEGAFACE R-30、MEGAF ACE R-90、MEGAFACE F-410、MEGAFACE F-411、MEGAFACE F-443、MEGAFACE F-445、MEGAFACE F-470、MEGAFACE F-477、MEGAFACE F-479、MEGAFACE F-482、MEGAFACE F-483( or more), EF301, EFTOP EF, EFTOP EF351, EFTOP EF352 (manufactured by Mitsubishi material electronics, inc.), surflon S-381, surflon S-382, surflon S-383, surflon S-393, surflon SC-101, surflon SC-105, KH-40, SA-100 (manufactured by AGC definition (Inc.), trade names E1830, E5844 (manufactured by Mitsubishi gold densification Studies), BM-1000, BM-1100, BYK-352, BYK-353, and BYK-361N (manufactured by BYK-361). BM Chemie company). The leveling agent may be used alone or in combination of 2 or more.
The content of the leveling agent is preferably 0.01 to 5 parts by mass, more preferably 0.05 to 3 parts by mass, per 100 parts by mass of the polymerizable liquid crystal compound. If the content of the leveling agent is within the above range, the resulting liquid crystal cured film tends to be smoother, and is therefore preferable.
By compounding an antioxidant, the polymerization reaction of the polymerizable liquid crystal compound can be controlled. The antioxidant may be a primary antioxidant selected from a phenol-based antioxidant, an amine-based antioxidant, a quinone-based antioxidant and a nitroso-based antioxidant, or may be a secondary antioxidant selected from a phosphorus-based antioxidant and a sulfur-based antioxidant. In order to polymerize the polymerizable liquid crystal compound without disturbing the alignment of the polymerizable liquid crystal compound, the content of the antioxidant is, for example, 0.01 to 10 parts by mass, preferably 0.1 to 5 parts by mass, and more preferably 0.1 to 3 parts by mass, per 100 parts by mass of the polymerizable liquid crystal compound. The antioxidant may be used alone or in combination of 2 or more.
In addition, by using a photosensitizing agent, the photopolymerization initiator can be made highly sensitive. Examples of the photosensitizing agent include xanthones such as xanthone and thioxanthone, anthracenes having a substituent such as an alkyl ether, phenothiazines, and rubrene. The photosensitizers may be used singly or in combination of 2 or more. The content of the photosensitizing agent is, for example, 0.01 to 10 parts by mass, preferably 0.05 to 5 parts by mass, and more preferably 0.1 to 3 parts by mass, relative to 100 parts by mass of the polymerizable liquid crystal compound.
The polymerizable liquid crystal composition can be obtained by stirring the components other than the polymerizable liquid crystal compound, such as the compound (a), the polymerizable liquid crystal compound, and the solvent, at a predetermined temperature.
The optical film can be produced, for example, as follows. That is, first, a coating film of the polymerizable liquid crystal composition is formed. The polymerizable liquid crystal compound is oriented in the horizontal direction with respect to the plane of the coating film. The polymerizable liquid crystal composition is cured while maintaining the horizontally aligned state of the polymerizable liquid crystal compound. Thereby producing an optical film. As a method of aligning the polymerizable liquid crystal compound in the horizontal direction, for example, a method of applying a polymerizable liquid crystal composition containing a rod-like polymerizable liquid crystal compound which is easily horizontally aligned to a later-described horizontal alignment film is mentioned.
The optical film preferably satisfies the following formula (1) and (2). By satisfying these equations, the optical film improves the reflection hue and tends to be less likely to be colored in black display when the circularly polarizing plate provided with the optical film is used in an organic EL display device.
0.82≤Re(450)/Re(550)≤0.98(1)
100nm≤Re(550)≤160nm(2)
[ Wherein Re (450) represents the in-plane phase difference value for light having a wavelength of 450nm, and Re (550) represents the in-plane phase difference value for light having a wavelength of 550 nm. ]
From the same point of view, re (450)/Re (550) is preferably 0.70 or more, more preferably 0.78 or more, and further preferably 0.95 or less, more preferably 0.92 or less.
From the same viewpoint, re (550) is preferably 130nm or more, and more preferably 150nm or less.
Re (450) may be 110nm or more and 130nm or less.
Re (630) may be 135nm or more and 155nm or less.
Re (630)/Re (550) may be 0.95 or more and may be 1.05 or less. Re (630) represents the in-plane phase difference value for light of wavelength 630 nm.
The in-plane retardation value is determined by the following formula (3). Therefore, the in-plane retardation (Re (λ)) of the optical film at the wavelength λ (nm) can be adjusted by changing the three-dimensional refractive index and the thickness d. The three-dimensional refractive index depends on the molecular structure and the alignment state of the polymerizable liquid crystal compound.
Re(λ)=(nx(λ)-ny(λ))×d(3)
[ Wherein nx (λ) represents a principal refractive index at a wavelength λ in a plane of the optical film, ny (λ) represents a refractive index at a wavelength λ in the same plane as nx and in a direction orthogonal to the direction of nx, and d represents a thickness of the optical film. ]
The thickness of the optical film is preferably 0.5 to 5.0. Mu.m, more preferably 0.8 to 4. Mu.m, and still more preferably 1.0 to 3.5. Mu.m.
[ Laminate ]
The laminate according to the present embodiment (hereinafter, also simply referred to as "laminate") includes the optical film according to the above embodiment and the horizontal alignment film. The optical film may be said to be a horizontally oriented liquid crystal cured film in the laminate.
(Horizontal alignment film)
The horizontal alignment film has an alignment control force that aligns the polymerizable liquid crystal compound in a horizontal direction with respect to the film plane of the liquid crystal cured film. The orientation control force can be arbitrarily adjusted by the kind of the orientation film, the surface state, the rubbing condition, and the like, and in the case where the orientation film is formed of a photo-alignment polymer, it can be arbitrarily adjusted by the polarized light irradiation condition, and the like.
The horizontal alignment film preferably has solvent resistance that does not dissolve due to application of the polymerizable liquid crystal composition or the like, and also has heat resistance for removal of the solvent and heat treatment for alignment of the polymerizable liquid crystal compound to be described later. Examples of the horizontal alignment film include a rubbing alignment film, a photo-alignment film, and a groove alignment film having a concave-convex pattern and a plurality of grooves on the surface. From the viewpoint of accuracy and quality of the orientation angle, a photo-alignment film is preferable.
The rubbing alignment film can be produced as follows, for example. That is, a composition (hereinafter, also referred to as "oriented polymer composition") containing an oriented polymer and a solvent is prepared. The oriented polymer composition is applied to the surface of a substrate, and the solvent is removed to obtain a coating film. The alignment control force is applied by rubbing the coating film. Thus, a rubbing alignment film can be obtained. Examples of the solvent include the same solvents as those which can be contained in the polymerizable liquid crystal composition.
Examples of the alignment polymer include polyamides having an amide bond in the molecule, gelatins, polyimides having an imide bond in the molecule, polyamic acids as hydrolysates thereof, polyvinyl alcohols, alkyl-modified polyvinyl alcohols, polyacrylamides, polyoxazoles, polyethylenimines, polystyrenes, polyvinylpyrrolidone, polyacrylic acids, and polyacrylates. Among them, polyvinyl alcohol is preferable. The alignment polymer may be used alone or in combination of 2 or more.
The concentration of the alignment polymer in the alignment polymer composition is preferably 0.1 to 20%, more preferably 0.1 to 10% in terms of solid content conversion relative to the solution, as long as the alignment polymer material is completely soluble in the solvent.
As the alignment polymer composition, a commercially available alignment film material can be used as it is. Examples of commercially available alignment film materials include SUNEVER (registered trademark, manufactured by Nissan chemical industries, ltd.), optomer (registered trademark, manufactured by JSR, ltd.), and the like.
The photo-alignment film can be produced, for example, as follows. That is, a composition (hereinafter, also referred to as a "composition for forming a photo-alignment film") containing at least one of a polymer and a monomer having a photoreactive group and a solvent is prepared. The composition for forming a photo-alignment film is applied to the surface of a substrate, and the solvent is removed to obtain a coating film. Polarized light is irradiated to the coating film. Thus, a photo-alignment film can be obtained. ) The photo-alignment film is also advantageous in that the direction of the alignment control force can be arbitrarily controlled by selecting the polarization direction of the irradiated polarized light.
The photoreactive group is a group that generates liquid crystal aligning ability by irradiation with light. Specifically, examples thereof include photoreactive groups that are involved in the alignment induction or isomerization reaction, dimerization reaction, photocrosslinking reaction, photodecomposition reaction, or the like of molecules generated by light irradiation and that are sources of liquid crystal alignment ability. Among them, a group participating in dimerization reaction or photocrosslinking reaction is preferable in view of excellent orientation. The photoreactive group is preferably a group having an unsaturated bond, particularly a double bond, and particularly preferably a group having at least one selected from the group consisting of a carbon-carbon double bond (c=c bond), a carbon-nitrogen double bond (c=n bond), a nitrogen-nitrogen double bond (n=n bond), and a carbon-oxygen double bond (c=o bond).
Examples of the photoreactive group having a c=c bond include a vinyl group, a polyalkenyl group, a stilbene azolyl group (stilbazole group), a stilbene azolium group (stilbazolium group), a chalcone group, and a cinnamoyl group. Examples of the photoreactive group having a c=n bond include a group having a structure such as an aromatic schiff base or an aromatic hydrazone. Examples of the photoreactive group having an n=n bond include an azo phenyl group, an azo naphthyl group, an aromatic heterocyclic azo group, a disazo group, a formazan (formazan) group, a group having an azobenzene oxide structure, and the like. Examples of the photoreactive group having a c=o bond include a benzophenone group, a coumarin group, an anthraquinone group, and a maleimide group. These groups may have substituents such as alkyl, alkoxy, aryl, allyloxy, cyano, alkoxycarbonyl, hydroxyl, sulfonic acid, haloalkyl, and the like.
The photoreactive group is preferably a photoreactive group involved in a photodimerization reaction, and is preferably a cinnamoyl group or a chalcone group in view of the fact that the amount of polarized light irradiation required for photoalignment is small, and a photoalignment film excellent in thermal stability and temporal stability is easily obtained. The polymer having a photoreactive group that forms the horizontal alignment film is particularly preferably a polymer having a cinnamoyl group in which the terminal portion of the side chain of the polymer has a cinnamic acid structure, because adhesion to the horizontal alignment liquid crystal cured film can be further improved when the horizontal alignment liquid crystal cured film is formed of a polymerizable liquid crystal compound having a (meth) acryloyloxy group as a polymerizable group.
Examples of the solvent contained in the composition for forming a photo-alignment film include the same solvents as those contained in the polymerizable liquid crystal composition. The solvent may be appropriately selected according to the solubility of the polymer or monomer having a photoreactive group.
The content of the polymer or monomer having a photoreactive group in the composition for forming a photoalignment film may be appropriately adjusted according to the kind of the polymer or monomer and the thickness of the photoalignment film to be targeted. The content is preferably set to be at least 0.2 mass%, more preferably in the range of 0.3 to 10 mass%, based on the mass of the composition for forming a photo-alignment film. In addition, from the viewpoint of ease of production, in the case where the horizontally oriented liquid crystal cured film is formed of a polymerizable liquid crystal compound having a (meth) acryloyloxy group as a polymerizable group, the polymer forming the photo-alignment film is preferably a (meth) acrylic polymer, in terms of improving adhesion to the horizontally oriented liquid crystal cured film. The composition for forming a photo-alignment film may contain a polymer material such as polyvinyl alcohol or polyimide, and a photosensitizing agent, so long as the properties of the photo-alignment film are not significantly impaired.
A groove (oriented film) is a film having a concave-convex pattern or a plurality of grooves (grooves) on the film surface. In the case of applying a polymerizable liquid crystal compound to a film having a plurality of linear grooves arranged at equal intervals, the liquid crystal molecules are aligned in a direction along the grooves.
The thickness of the alignment film (alignment film or photo-alignment film containing an alignment polymer) is, for example, 10 to 10000nm, preferably 10 to 1000nm, more preferably 10 to 500nm or less, still more preferably 10 to 300nm, particularly preferably 50 to 250nm.
(Curable resin)
The laminate may include a cured resin layer. The thickness of the cured resin layer is 0.1 to 10 μm, preferably 0.5 to5 μm, from the viewpoint of thickness reduction of the laminate.
Examples of the cured resin layer include films of cycloolefin polymers (COPs), polyethylene terephthalate (PET), cellulose Triacetate (TAC), and the like, which are also used as a base material described later, and cured products of a composition for forming a cured resin layer containing a polymerizable monomer, but from the viewpoint of film formation, the cured resin layer is preferably a cured product of a composition for forming a cured resin layer. The cured resin layer may be composed of a plurality of layers, but is preferably 2 or less layers, more preferably a single layer, from the viewpoint of productivity. In addition, from the viewpoint of not affecting the optical characteristics of the multilayer, it is preferable that the cured resin layer is optically isotropic.
In the present disclosure, the resin contained in the cured resin layer is sometimes referred to as a resin based on the largest number of functional groups among the contained functional groups. For example, when the number of acryloyloxy groups in the functional groups contained in the resin is the largest, the resin is referred to as an acrylic resin, and when the number of epoxy groups in the functional groups contained in the resin is the largest, the resin is referred to as an epoxy resin or the like.
The cured resin layer preferably contains at least 1 selected from the group consisting of acrylic resin, epoxy resin, oxetane resin, polyurethane resin, and melamine resin. By including at least 1 resin as described above, the curability is high, and the reliability when combined with a horizontally oriented liquid crystal cured film is easily improved.
The composition for forming a cured resin layer constituting the cured resin layer is a composition containing a curable polymerizable monomer such as a radical polymerizable monomer, a cationic polymerizable monomer, or a thermal polymerizable monomer as a curable material, and more preferably contains a radical polymerizable monomer or a cationic polymerizable monomer, from the viewpoint of high reaction rate and improved productivity, and from the viewpoint of easy improvement of reliability in combination with a horizontally oriented liquid crystal cured film.
The cured resin layer preferably contains at least 1 selected from the group consisting of acrylic resin, epoxy resin, oxetane resin, polyurethane resin, and melamine resin. By including such a resin in the cured resin layer, the curability is high, and the reliability when combined with the horizontally oriented liquid crystal cured film is easily improved.
The composition for forming a cured resin layer contains a curable polymerizable monomer as a curable material. Examples of the polymerizable monomer include a radical polymerizable monomer, a cation polymerizable monomer, and a thermal polymerizable monomer. The polymerizable monomer is preferably a radical polymerizable monomer or a cation polymerizable monomer from the viewpoints of high reaction rate and improved productivity, and easy improvement of reliability in combination with the horizontally oriented liquid crystal cured film.
Examples of such a radically polymerizable monomer include (meth) acrylate compounds such as polyfunctional (meth) acrylate compounds, urethane (meth) acrylate compounds such as polyfunctional urethane (meth) acrylate compounds, epoxy (meth) acrylate compounds such as polyfunctional epoxy (meth) acrylate compounds, carboxyl-modified epoxy (meth) acrylate compounds, polyester (meth) acrylate compounds, and the like. The number of these may be 1 alone, or 2 or more may be used in combination.
The polymerizable monomer is preferably a polymerizable monomer having a (meth) acryloyloxy group, more preferably a polyfunctional (meth) acrylate compound, and even more preferably a polyfunctional acrylate compound, from the viewpoints of improving reliability in combination with a horizontally oriented liquid crystal cured film, improving adhesion to an adjacent layer, and improving productivity.
Examples of the polyfunctional acrylate compound include a 2-functional (meth) acrylate monomer having 2 (meth) acryloyloxy groups in the molecule and a 3-functional or more (meth) acrylate monomer having 3 or more (meth) acryloyloxy groups in the molecule.
In the present specification, "(meth) acrylate" means "acrylate" or "methacrylate", "(meth) acryl" means "acryl" or "methacryl", and "multifunctional (meth) acrylate compound" means a compound having 2 or more (meth) acryloyloxy groups in the molecule.
The polyfunctional (meth) acrylate compound may be used alone or in combination of 1 or more than 2. In the case where 2 or more kinds of the multifunctional (meth) acrylate compounds are used, the number of (meth) acryloyloxy groups contained in each of the multifunctional (meth) acrylate compounds may be the same or different.
Examples of the monomer having 2 (meth) acryloyloxy groups in the molecule include polyoxyalkylene glycol di (meth) acrylate such as ethylene glycol di (meth) acrylate, 1, 3-butanediol di (meth) acrylate, 1, 4-butanediol di (meth) acrylate, alkylene glycol di (meth) acrylate such as 1, 6-hexanediol di (meth) acrylate, 1, 9-nonanediol di (meth) acrylate and neopentyl glycol di (meth) acrylate, di (meth) acrylate of aliphatic polyhydric alcohols such as diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate and polybutylene glycol di (meth) acrylate, halogen-substituted alkylene glycol di (meth) acrylate such as tetrafluoroethylene glycol di (meth) acrylate, trimethylolpropane di (meth) acrylate, ditrimethylolpropane di (meth) acrylate, pentaerythritol di (meth) acrylate, hydrogenated dicyclopentadiene di (meth) acrylate, hydrogenated dicyclopentadiene such as tricyclodecanedimethanol di (meth) acrylate or tricyclodecane dimethanol di (meth) acrylate, 1, 3-dioxane-2, 5-diylbis (meth) acrylate [ alias: dioxane diol di (meth) acrylate ], dioxane diol such as dioxane diol di (meth) acrylate ], bis (meth) acrylate of dioxane dimethanol, bis (meth) acrylate of bisphenol A or alkylene oxide adduct of bisphenol F such as bisphenol A ethylene oxide adduct diacrylate, bis (meth) acrylate of bisphenol A ethylene oxide adduct of bisphenol F, bisphenol A or bisphenol F ethylene oxide adduct of bisphenol A ethylene oxide adduct of bisphenol F), bis (meth) acrylate of polysiloxane di (meth) acrylate, neopentyl glycol hydroxypivalate di (meth) acrylate, 2-bis [4- (meth) acryloyloxyethoxy ethoxyphenyl ] propane, 2-bis [4- (meth) acryloyloxyethoxy-cyclohexyl ] propane, 2- (2-hydroxy-1, 1-diethyl) -5-dihydroxy (meth) acrylate, and the like.
Examples of the monomer having 3 (meth) acryloyloxy groups in the molecule include glycerol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, ditrimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, a reactant of pentaerythritol tri (meth) acrylate with an acid anhydride, caprolactone-modified trimethylolpropane tri (meth) acrylate, caprolactone-modified pentaerythritol tri (meth) acrylate, ethylene oxide-modified trimethylolpropane tri (meth) acrylate, ethylene oxide-modified pentaerythritol tri (meth) acrylate, propylene oxide-modified trimethylolpropane tri (meth) acrylate, propylene oxide-modified pentaerythritol tri (meth) acrylate, isocyanurate tri (meth) acrylate, a reactant of caprolactone-modified pentaerythritol tri (meth) acrylate with an acid anhydride, a reactant of ethylene oxide-modified pentaerythritol tri (meth) acrylate with an acid anhydride, and a reactant of propylene oxide-modified pentaerythritol tri (meth) acrylate with an acid anhydride.
Examples of the monomer having 4 (meth) acryloyloxy groups in the molecule include ditrimethylolpropane tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol tetra (meth) acrylate, tripentaerythritol tetra (meth) acrylate, caprolactone-modified pentaerythritol tetra (meth) acrylate, caprolactone-modified tripentaerythritol tetra (meth) acrylate, ethylene oxide-modified pentaerythritol tetra (meth) acrylate, ethylene oxide-modified tripentaerythritol tetra (meth) acrylate, propylene oxide-modified pentaerythritol tetra (meth) acrylate, and propylene oxide-modified tripentaerythritol tetra (meth) acrylate.
Examples of the monomer having 5 (meth) acryloyloxy groups in the molecule include dipentaerythritol penta (meth) acrylate, tripentaerythritol penta (meth) acrylate, a reactant of dipentaerythritol penta (meth) acrylate and an acid anhydride, caprolactone-modified dipentaerythritol penta (meth) acrylate, caprolactone-modified tripentaerythritol penta (meth) acrylate, ethylene oxide-modified dipentaerythritol penta (meth) acrylate, ethylene oxide-modified tripentaerythritol penta (meth) acrylate, propylene oxide-modified dipentaerythritol penta (meth) acrylate, propylene oxide-modified tripentaerythritol penta (meth) acrylate, a reactant of caprolactone-modified dipentaerythritol penta (meth) acrylate and an acid anhydride, a reactant of ethylene oxide-modified dipentaerythritol penta (meth) acrylate and an acid anhydride, and the like.
Examples of the monomer having 6 (meth) acryloyloxy groups in the molecule include dipentaerythritol hexa (meth) acrylate, tripentaerythritol hexa (meth) acrylate, caprolactone-modified dipentaerythritol hexa (meth) acrylate, caprolactone-modified tripentaerythritol hexa (meth) acrylate, ethylene oxide-modified dipentaerythritol hexa (meth) acrylate, ethylene oxide-modified tripentaerythritol hexa (meth) acrylate, propylene oxide-modified dipentaerythritol hexa (meth) acrylate, and propylene oxide-modified tripentaerythritol hexa (meth) acrylate.
Examples of the monomer having 7 (meth) acryloyloxy groups in the molecule include tripentaerythritol hepta (meth) acrylate, a tripentaerythritol hepta (meth) acrylate-anhydride reactant, caprolactone-modified tripentaerythritol hepta (meth) acrylate-anhydride reactant, ethylene oxide-modified tripentaerythritol hepta (meth) acrylate-anhydride reactant, propylene oxide-modified tripentaerythritol hepta (meth) acrylate, and propylene oxide-modified tripentaerythritol hepta (meth) acrylate-anhydride reactant.
Examples of the monomer having 8 (meth) acryloyloxy groups in the molecule include tripentaerythritol octa (meth) acrylate, caprolactone-modified tripentaerythritol octa (meth) acrylate, ethylene oxide-modified tripentaerythritol octa (meth) acrylate, and propylene oxide-modified tripentaerythritol octa (meth) acrylate.
Examples of the cationically polymerizable monomer include an epoxy compound having an epoxy group and an oxetane compound having an oxetanyl group.
The epoxy compound is a polymerizable monomer having at least 1 or more epoxy groups in the molecule. Examples of the epoxy compound include alicyclic epoxy compounds, aromatic epoxy compounds, and aliphatic epoxy compounds.
The alicyclic epoxy compound is a compound having at least 1 epoxy group directly bonded to an alicyclic ring in a molecule. Examples of the alicyclic epoxy compound include 3, 4-epoxycyclohexylmethyl 3, 4-epoxycyclohexane carboxylate, 3, 4-epoxy-6-methylcyclohexylmethyl 3, 4-epoxy-6-methylcyclohexane carboxylate, ethylenebis (3, 4-epoxycyclohexane carboxylate), bis (3, 4-epoxycyclohexylmethyl) adipate, bis (3, 4-epoxy6-methylcyclohexylmethyl) adipate, diethylene glycol bis (3, 4-epoxycyclohexylmethyl) ether, and ethylene glycol bis (3, 4-epoxycyclohexylmethyl) ether. These alicyclic epoxy compounds may be used singly or in combination of 1 or more than 2.
The aromatic epoxy compound is a compound having an aromatic ring and an epoxy group in a molecule. Specific examples thereof include bisphenol epoxy compounds such as diglycidyl ether of bisphenol a, diglycidyl ether of bisphenol F, diglycidyl ether of bisphenol S, and oligomers thereof, novolacs such as phenol novolacs, cresol novolacs, and hydroxybenzaldehyde phenol novolacs, multifunctional epoxy compounds such as glycidyl ether of 2,2', 4' -tetrahydroxydiphenylmethane, and glycidyl ether of 2,2', 4' -tetrahydroxybenzophenone, and multifunctional epoxy resins such as epoxidized polyvinylphenol. These aromatic epoxy compounds may be used singly or in combination of 1 or more than 2.
In the case of the hydrogenated epoxy compound, the core hydride of the aromatic epoxy compound described above becomes the hydrogenated epoxy compound. These can be produced by selectively hydrogenating an aromatic polyol, typically a bisphenol, which is a raw material for the corresponding aromatic epoxy compound, in the presence of a catalyst under pressure, reacting the thus-obtained polyol, typically a hydrogenated bisphenol, with epichlorohydrin to produce a chlorohydrin ether, and further subjecting the chlorohydrin ether to intramolecular ring closure with a base. These hydrogenated epoxy compounds may be used singly or in combination of 1 or more than 2.
Among the aliphatic epoxy compounds, polyglycidyl ethers of aliphatic polyols or alkylene oxide adducts thereof are included. Specific examples thereof include diglycidyl ether of neopentyl glycol, diglycidyl ether of 1, 4-butanediol, diglycidyl ether of 1, 6-hexanediol, triglycidyl ether of glycerin, triglycidyl ether of trimethylolpropane, diglycidyl ether of polyethylene glycol, diglycidyl ether of propylene glycol, polyglycidyl ether of polyether polyol obtained by adding 1 or 2 or more alkylene oxides (ethylene oxide, propylene oxide) to aliphatic polyol such as ethylene glycol, propylene glycol, glycerin, and the like. These aliphatic epoxy compounds may be used singly or in combination of 1 or more than 2.
The oxetane compound is a compound having at least 1 oxetane group in the molecule, and specific examples thereof include 3-ethyl-3-hydroxymethyloxetane (also referred to as oxetane alcohol), 2-ethylhexyl oxetane, 1, 4-bis [ (3-ethyloxetan-3-yl) methoxy } methyl ] benzene (also referred to as xylylenedioxetane), 3-ethyl-3 [ (3-ethyloxetan-3-yl) methoxy } methyl ] oxetane, 3-ethyl-3- (phenoxymethyl) oxetane, 3- (cyclohexyloxy) methyl-3-ethyloxetane and the like.
Examples of the thermally polymerizable monomer include melamine compounds. Examples of the melamine compound include hexamethoxymethyl melamine, hexaethoxymethyl melamine, hexapropoxymethyl melamine, and hexabutoxymethyl melamine. The melamine compound may be used alone or in combination of 1 or more than 2.
Further, as the other polymerizable monomer, a combination of an isocyanate compound and an alcohol compound having a hydroxyl group in the molecule can be given, and a polyurethane resin can be produced. The isocyanate compound used for producing the polyurethane resin and the urea resin generally has 2 or more isocyanate groups (-NCO) in the molecule, and various diisocyanates having an aromatic, aliphatic or alicyclic structure can be used. Specific examples thereof include tetramethylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, 2, 4-toluene diisocyanate, 4 '-diphenyl diisocyanate, 1, 5-naphthalene diisocyanate, 3' -dimethyl-4, 4 '-diphenyl diisocyanate, xylene diisocyanate, trimethylhexamethylene diisocyanate, 4' -diphenylmethane diisocyanate, and nuclear hydrides of diisocyanates having aromatic rings among them. Further, the alcohol compound used for the polyurethane resin generally has 2 or more hydroxyl groups in the molecule, and examples thereof include ethylene glycol, 1, 2-propylene glycol, 1, 3-propylene glycol, diethylene glycol, dipropylene glycol, neopentyl glycol, 1, 3-butanediol, 1, 4-butanediol, 1, 6-hexanediol, 1, 9-nonanediol, 1, 10-decanediol, 2, 4-trimethyl-1, 3-pentanediol, 3-methyl-1, 5-pentanediol, neopentyl glycol ester of hydroxypivalic acid, 1, 4-cyclohexanediol, spiroglycol, tricyclodecanedimethanol, bisphenol A, hydrogenated bisphenol A, trimethylolethane, trimethylolpropane, glycerol, 3-methylpentane-1, 3, 5-triol, pentaerythritol, dipentaerythritol, tripentaerythritol, glucose and the like.
The polymerizable monomer may be suitably selected from the viewpoint of suppressing warpage due to heating during and after curing, the viewpoint of improving processing characteristics, the viewpoint of adjusting adhesion to a substrate or a liquid crystal cured film, the viewpoint of improving productivity, the viewpoint of improving solvent resistance, and the viewpoint of improving reliability in combination with a horizontally oriented liquid crystal cured film. In the present disclosure, the cured resin layer preferably contains at least 1 selected from the group consisting of acrylic resin, epoxy resin, oxetane resin, polyurethane resin, and melamine resin. For example, 2 or more radical polymerizable monomers may be used, or a combination of a radical polymerizable monomer and a cation polymerizable monomer may be used. In particular, from the viewpoint of improving productivity, it is preferable to contain a radical polymerizable monomer.
The composition for forming a cured resin layer may contain, in addition to the polymerizable monomer, additives such as a photopolymerization initiator, a thermal polymerization initiator, a solvent, an antioxidant, a photosensitizing agent, a leveling agent, an antioxidant, a chain transfer agent, a light stabilizer, an adhesion promoter, a filler, a flow regulator, a plasticizer, a defoaming agent, a pigment, an antistatic agent, and an ultraviolet absorber. These additives are usually 0.1 to 15% by mass relative to the mass of the solid content of the cured resin layer-forming composition. The solid content of the composition for forming a cured resin layer, when the composition for forming a cured resin layer contains a solvent, means the total amount of the components after the solvent is removed from the composition.
The content of the polymerizable monomer in the curable resin layer-forming composition is preferably 50 parts by mass or more, more preferably 60 parts by mass or more, based on 100 parts by mass of the solid content of the composition. If the content is within the above range, the reliability in combination with the horizontally oriented liquid crystal cured film can be easily improved.
The composition for forming a cured resin layer preferably contains a polymerization initiator. The polymerizable initiator may be a photopolymerization initiator, a thermal polymerization initiator, or the like, but from the viewpoint of improving productivity, it is preferable to use a photopolymerization initiator. The photopolymerization initiator is not particularly limited as long as it can initiate curing of the polymerizable monomer by irradiation with active energy rays such as visible rays, ultraviolet rays, X rays, and electron rays, and a photo radical polymerization initiator and a photo cation polymerization initiator may be suitably used depending on the kind of the polymerizable monomer. The photo-radical polymerization initiator and the photo-cation polymerization initiator are specifically the same polymerization initiators as those exemplified above as polymerization initiators that can be incorporated in the polymerizable liquid crystal composition for forming a horizontally oriented liquid crystal cured film.
When the composition for forming a cured resin layer contains a polymerization initiator, the content of the polymerization initiator is preferably 0.1 to 10 parts by mass, more preferably 0.5 to 7 parts by mass, relative to 100 parts by mass of the total amount of the curable compounds. If the content of the polymerization initiator is not less than the above-mentioned lower limit, the polymerization initiator can be sufficiently exhibited, and if the content of the polymerization initiator is not more than the above-mentioned upper limit, the polymerization initiator is less likely to remain.
When the curable resin layer-forming composition contains a solvent, the solvent may be appropriately selected from the viewpoint of sufficiently dissolving the polymerizable monomer, the polymerization initiator, and the like added to the curable resin layer-forming composition, and the viewpoint of not dissolving the base material, and for example, a solvent usable in the polymerizable liquid crystal composition for forming a horizontally oriented liquid crystal cured film may be used. The content of the solvent may be 1 to 10000 parts by mass, preferably 10 to 1000 parts by mass, more preferably 20 to 500 parts by mass, relative to 100 parts by mass of the total amount of the components contained in the composition for forming a cured resin layer.
In the laminate of the present disclosure, it is preferable that the cured resin layer is optically isotropic. If the cured resin layer is optically isotropic, the cured resin layer, when combined with the horizontally oriented liquid crystal cured film, does not affect the optical properties of the horizontally oriented liquid crystal cured film, and a laminate having high optical properties can be obtained.
When the laminate includes a cured resin layer, the lamination order of the layers of the laminate may be appropriately selected, but the laminate preferably has a laminated structure including a horizontally oriented liquid crystal cured film, a horizontally oriented film, and a cured resin layer in this order. The laminate may further include an adhesive layer.
The laminate can be produced, for example, by a method comprising the following steps.
A step of forming a cured resin layer
A step of forming a horizontal alignment film
A step of forming a horizontally oriented liquid crystal cured film (optical film) on the horizontally oriented film
(Step of forming cured resin layer)
The curable resin layer can be obtained, for example, by applying the composition for forming a curable resin layer to a substrate, and then drying and removing the solvent in the presence of the solvent to cure the polymerizable monomer.
Examples of the substrate include a glass substrate and a film substrate, but from the viewpoint of processability, a resin film substrate is preferable. Examples of the resin constituting the film base material include polyolefin such as polyethylene, polypropylene and norbornene polymer, cyclic olefin resin, polyvinyl alcohol, polyethylene terephthalate, polymethacrylate, polyacrylate, cellulose ester such as cellulose triacetate, cellulose diacetate and cellulose acetate propionate, polyethylene naphthalate, polycarbonate, polysulfone, polyether sulfone, polyether ketone, polyphenylene sulfide and polyphenylene oxide. Such a resin can be formed into a film by known means such as solvent casting or melt extrusion to prepare a substrate. The surface of the substrate (for example, the surface to be bonded to the adhesive layer) may be subjected to a surface treatment such as a mold release treatment such as a silicone treatment, a corona treatment, a plasma treatment, or the like.
As the base material, a commercially available product can be used. Examples of the commercially available cellulose ester substrates include cellulose ester substrates manufactured by Fuji Photo Film, such as Fujitac Film, cellulose ester substrates manufactured by KONICA MINOLTA Opto, such as "KC8UX2M", "KC8UY", and "KC4 UY". Examples of the commercially available cycloolefin resin include cycloolefin resins produced by Ti cona (germany) such as "Topas (registered trademark)", cycloolefin resins produced by JSR (registered trademark) ", which are produced by zeton (registered trademark)", cycloolefin resins produced by mitsunobu chemical company such as "ZEONOR (registered trademark)", and cycloolefin resins produced by Zeon (registered trademark) ", which are produced by Zeon (japan) and" Apel (registered trademark) ". Commercially available cycloolefin resin base materials can also be used. Examples of the commercially available cycloolefin resin base material include cycloolefin resin base materials made by Seattle chemical industries, inc., such as "Esushina (registered trademark)" and "SCA40 (registered trademark)", cycloolefin resin base materials made by OPTES, inc., such as "ZeonorFilm (registered trademark)", and cycloolefin resin base materials made by JSR, inc., such as "Arton Film (registered trademark)".
The thickness of the base material is usually 5 to 300. Mu.m, preferably 10 to 150. Mu.m, from the viewpoints of thinning and easiness of peeling of the base material.
Examples of the method of applying the composition for forming a cured resin layer to a substrate or the like include known methods such as spin coating, extrusion, gravure coating, die coating, bar coating, coating by an applicator method, and printing by a flexographic method.
In the case where the curable resin layer-forming composition contains a solvent, examples of the method for drying and removing the solvent include a natural drying method, a pneumatic drying method, a heat drying method, and a reduced pressure drying method.
(Horizontal alignment film Forming Process)
When the horizontal alignment film included in the laminate is a rubbing alignment film, the alignment polymer composition is applied to the cured resin layer, and the solvent is removed to form a coating film. Then, the coating film is rubbed, thereby obtaining a horizontally oriented film.
Examples of the method of applying the alignment polymer composition to the cured resin layer include known methods such as spin coating, extrusion, gravure coating, die coating, bar coating, coating by an applicator, and printing by a flexographic printing.
Examples of the method for drying and removing the solvent from the oriented polymer composition include a natural drying method, a pneumatic drying method, a heat drying method and a reduced pressure drying method.
As a method of the rubbing treatment, for example, a method of bringing the coating film into contact with a rubbing roller around which a rubbing cloth is wound and rotated is given. In the rubbing treatment, a plurality of regions (patterns) having different alignment directions can be formed on the alignment film by masking.
When the horizontal alignment film is a photo-alignment film, a composition for forming a photo-alignment film is applied to the cured resin layer, and after the solvent is removed, polarized light is irradiated to obtain a photo-horizontal alignment film. The polarized light of the illumination is preferably polarized UV light.
As a method of applying the composition for forming a photo-alignment film on the cured resin layer and a method of removing the solvent from the applied composition for forming a photo-alignment film, the same methods as those listed in the alignment polymer composition can be mentioned.
In the case of irradiating polarized light, polarized U V light may be directly irradiated to a product obtained by removing a solvent from the composition for forming a photo-alignment film applied to the surface on which a horizontal alignment film is to be formed. In addition, it is particularly preferable that the polarized light is substantially parallel light. The wavelength of the irradiated polarized light is preferably a wavelength in a wavelength region where the photoreactive group of the polymer or monomer having the photoreactive group can absorb light energy. Specifically, UV (ultraviolet) having a wavelength of 250 to 400nm is preferable. Examples of the light source used for the polarized light irradiation include ultraviolet light lasers such as xenon lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, metal halide lamps, krF, arF, and the like, and more preferably high-pressure mercury lamps, ultra-high-pressure mercury lamps, and metal halide lamps. Among them, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, and a metal halide lamp are preferable because of the high emission intensity of ultraviolet rays having a wavelength of 313 nm. Polarized UV light can be irradiated by passing light from a light source through an appropriate polarizer for irradiation. As the polarizer, a polarizing prism such as a polarizing filter, a gram-thompson, a gram-taylor, or a wire grid type polarizer can be used.
In rubbing or polarized light irradiation, a plurality of regions (patterns) having different directions of alignment of the liquid crystal can be formed by masking.
Examples of the method for obtaining the groove alignment film include a method for forming a concave-convex pattern by exposing the surface of a photosensitive polyimide film through an exposure mask having a slit in a pattern shape, and then performing development and rinsing processes, a method for forming a layer of UV curable resin before curing on a plate-shaped master having grooves on the surface, a method for transferring the formed resin layer to the cured resin layer and then curing, and a method for pressing a roll-shaped master having a plurality of grooves on a film of UV curable resin before curing formed on the cured resin layer, thereby forming concave-convex patterns, and then curing.
In the case where the laminate does not include a cured resin layer, a horizontal alignment film can be formed on a substrate.
(Step of forming a cured film of liquid Crystal in horizontal orientation)
In this step, a polymerizable liquid crystal composition is applied to the horizontal alignment film to obtain a coating film. The obtained coating film is heated to a temperature equal to or higher than the liquid crystal phase transition temperature of the polymerizable liquid crystal compound contained in the polymerizable liquid crystal composition. Thus, the solvent is removed from the coating film by drying, and the polymerizable liquid crystal compound is oriented in the horizontal direction.
The heating temperature of the coating film can be appropriately determined in consideration of the material of the polymerizable liquid crystal compound used, the substrate on which the coating film is formed, and the like. In order to put the polymerizable liquid crystal compound into a horizontally aligned state while removing the solvent contained in the polymerizable liquid crystal composition, the heating temperature is preferably a temperature 3 ℃ or higher, more preferably 5 ℃ or higher than the liquid crystal phase (nematic phase) transition temperature of the polymerizable liquid crystal compound. The upper limit of the heating temperature is not particularly limited, but is preferably 180 ℃ or less, more preferably 150 ℃ or less, in order to avoid damage to the coating film, the substrate, or the like caused by heating. The nematic phase transition temperature can be measured using, for example, a polarizing microscope equipped with a temperature adjustment stage, a Differential Scanning Calorimeter (DSC), a thermogravimetric analysis device (TG-DTA), or the like.
The heating time may be appropriately determined depending on the heating temperature, the kind of the polymerizable liquid crystal compound to be used, the kind of the solvent, the boiling point thereof, the amount thereof, and the like. The heating time is, for example, 0.5 to 10 minutes, preferably 0.5 to 5 minutes.
The solvent may be removed from the coating film simultaneously with or independently of the heating of the polymerizable liquid crystal compound to a nematic phase transition temperature or higher, but is preferably simultaneously from the viewpoint of improving productivity. The removal of the solvent from the coating film is usually performed simultaneously with the heating of the polymerizable liquid crystal compound to a nematic phase transition temperature or higher, and a pre-drying step for properly removing the solvent in the coating film under the condition that the polymerizable liquid crystal compound contained in the coating film obtained from the polymerizable liquid crystal composition is not polymerized may be provided before the heating of the polymerizable liquid crystal compound to a liquid crystal phase transition temperature or higher. Examples of the drying method in the pre-drying step include a natural drying method, a ventilation drying method, a heating drying method, and a reduced pressure drying method, and the drying temperature (heating temperature) in the drying step can be appropriately determined according to the type of the polymerizable liquid crystal compound to be used, the type of the solvent, the boiling point thereof, the amount thereof, and the like.
Next, in the obtained dry coating film, the polymerizable liquid crystal compound is polymerized while maintaining the horizontally aligned state of the polymerizable liquid crystal compound, thereby forming a horizontally aligned liquid crystal cured film. The polymerization method is preferably a photopolymerization method, and the horizontally oriented liquid crystal cured film can be formed by irradiation with light from the side of the coated surface of the polymerizable liquid crystal composition. In photopolymerization, the light to be irradiated to the dried coating film may be appropriately selected depending on the type of photopolymerization initiator contained in the dried coating film, the type of polymerizable liquid crystal compound (particularly, the type of polymerizable group contained in the polymerizable liquid crystal compound), and the amount thereof. Specific examples thereof include 1 or more light and active electron rays selected from the group consisting of visible light, ultraviolet light, infrared light, X-rays, α -rays, β -rays and γ -rays. Among them, ultraviolet light is preferable from the viewpoint of easy control of the progress of polymerization reaction and the possibility of using a device widely used in the art as a photopolymerization device. The types of the polymerizable liquid crystal compound and the photopolymerization initiator contained in the polymerizable liquid crystal composition are preferably selected in advance so that photopolymerization can be performed by ultraviolet light. In addition, in the polymerization, the polymerization temperature can be controlled by cooling the dried coating film by an appropriate cooling means and simultaneously irradiating the film with light. If the polymerization of the polymerizable liquid crystal compound is carried out at a lower temperature by using such a cooling means, a horizontally oriented liquid crystal cured film can be formed appropriately even if a substrate having low heat resistance is used as the substrate.
Examples of the light source of the active energy ray include a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a xenon lamp, a halogen lamp, a carbon arc lamp, a tungsten lamp, a gallium lamp, an excimer laser, an LED light source that emits light in a wavelength range of 380 to 440nm, a chemical lamp, a black light lamp, a microwave-excited mercury lamp, and a metal halide lamp.
The ultraviolet irradiation intensity is, for example, 10 to 3,000mW/cm2. The irradiation time of the light is, for example, 0.1 seconds to 10 minutes, preferably 0.1 seconds to 5 minutes, more preferably 0.1 seconds to 3 minutes, and still more preferably 0.1 seconds to 1 minute. When the ultraviolet irradiation intensity is applied 1 or more times, the cumulative light amount is, for example, 10 to 3,000mJ/cm2, preferably 50 to 2,000mJ/cm2, more preferably 100 to 1,000mJ/cm2.
When the laminate further includes an adhesive layer, examples of the adhesive constituting the laminate include a pressure-sensitive adhesive, a dry-curable adhesive, and a chemically reactive adhesive. Examples of the chemically reactive adhesive include an active energy ray-curable adhesive.
The pressure sensitive adhesive typically comprises a polymer and may also comprise a solvent. Examples of the polymer include an acrylic polymer, a silicone polymer, a polyester, a polyurethane, and a polyether. Among them, an acrylic adhesive containing an acrylic polymer is preferable because it is excellent in optical transparency, has moderate wettability and cohesion, is excellent in adhesion, has high weather resistance and heat resistance, and is less likely to cause lifting and peeling under heating and humidification.
The acrylic polymer is preferably a copolymer of a (meth) acrylic acid ester in which the alkyl group of the ester moiety is an alkyl group having 1 to 20 carbon atoms such as methyl, ethyl, or butyl, and a (meth) acrylic monomer having a functional group such as (meth) acrylic acid or hydroxyethyl (meth) acrylate.
The pressure-sensitive adhesive containing such a copolymer is preferable because it is excellent in adhesion and can be removed relatively easily without generating a residual adhesive or the like on the transfer object even when it is removed after being attached to the transfer object. The glass transition temperature of the acrylic polymer is preferably 25 ℃ or less, more preferably 0 ℃ or less. The mass average molecular weight of such an acrylic polymer is preferably 10 ten thousand or more.
The solvent may be the same as that used in the polymerizable liquid crystal composition and the like. The pressure sensitive adhesive may contain a light diffusing agent. The light diffusing agent is an additive that imparts light diffusibility to the binder, and may be any fine particles having a refractive index different from that of the polymer contained in the binder. Examples of the light diffusing agent include fine particles made of an inorganic compound and fine particles made of an organic compound (polymer). Since the polymer contained in the binder including the acrylic polymer as an active ingredient has a refractive index of 1.4 to 1.6 in many cases, it is preferable to select the polymer appropriately from light diffusers having a refractive index of 1.2 to 1.8. The refractive index difference between the polymer contained as an active ingredient in the binder and the light diffusing agent is usually 0.01 or more, and is preferably 0.01 to 0.2 from the viewpoints of the brightness and display properties of the display device. The fine particles used as the light diffusing agent are preferably spherical fine particles and fine particles close to monodisperse fine particles, and more preferably fine particles having an average particle diameter of 2 to 6 μm. The refractive index can be measured by a general minimum deflection angle method or an Abbe refractometer.
Examples of the fine particles formed of an inorganic compound include alumina (refractive index 1.76) and silica (refractive index 1.45). Examples of the fine particles formed of the organic compound (polymer) include melamine beads (refractive index 1.57), polymethyl methacrylate beads (refractive index 1.49), methyl methacrylate/styrene copolymer resin beads (refractive index 1.50 to 1.59), polycarbonate beads (refractive index 1.55), polyethylene beads (refractive index 1.53), polystyrene beads (refractive index 1.6), polyvinyl chloride beads (refractive index 1.46), and silicone beads (refractive index 1.46). The content of the light diffusing agent is, for example, 3 to 30 parts by mass based on 100 parts by mass of the polymer.
The thickness of the pressure-sensitive adhesive may be determined according to its adhesion force and the like, and is therefore not particularly limited, and is, for example, 1 μm to 40 μm. The thickness is preferably 3 μm to 25 μm, more preferably 5 μm to 20 μm, from the viewpoints of workability, durability, and the like. By setting the thickness of the adhesive layer formed of the adhesive to 5 μm to 20 μm, the brightness when the display device is viewed from the front and the brightness when the display device is viewed from an oblique direction can be maintained, and the stain and blurring of the display image are less likely to occur.
The dry curable adhesive may contain a solvent. Examples of the dry curable adhesive include a polymer or a polyurethane resin containing a monomer having a proton functional group such as a hydroxyl group, a carboxyl group, or an amino group and an ethylenically unsaturated group as a main component, and a composition further containing a crosslinking agent or a curable compound such as a polyaldehyde, an epoxy compound, an epoxy resin, a melamine compound, a zirconia compound, and a zinc compound. Examples of the polymer of the monomer having a proton functional group such as a hydroxyl group, a carboxyl group or an amino group and an ethylenically unsaturated group include ethylene-maleic acid copolymer, itaconic acid copolymer, acrylic acid copolymer, acrylamide copolymer, saponified product of polyvinyl acetate, and polyvinyl alcohol resin.
Examples of the polyvinyl alcohol resin include polyvinyl alcohol, partially saponified polyvinyl alcohol, fully saponified polyvinyl alcohol, carboxyl-modified polyvinyl alcohol, acetoacetyl-modified polyvinyl alcohol, hydroxymethyl-modified polyvinyl alcohol, and amino-modified polyvinyl alcohol. The content of the polyvinyl alcohol resin in the aqueous adhesive binder is, for example, 1 to 10 parts by mass, preferably 1 to 5 parts by mass, per 100 parts by mass of water.
Examples of the polyurethane resin include polyester-based ionomer polyurethane resins. The polyester-based ionomer polyurethane resin is a polyurethane resin having a polyester skeleton, and is a resin in which a small amount of an ionic component (hydrophilic component) is introduced. The ionomer polyurethane resin is emulsified in water without using an emulsifier to form an emulsion, and thus can be produced into an aqueous adhesive. In the case of using a polyester-based ionomer polyurethane resin, it is effective to blend a water-soluble epoxy compound as a crosslinking agent.
Examples of the epoxy resin include polyamide epoxy resins obtained by reacting epichlorohydrin with polyamide polyamine obtained by reacting polyalkylene polyamine such as diethylenetriamine or triethylenetetramine with dicarboxylic acid such as adipic acid. Examples of the commercial products of the polyamide epoxy resin include Sumirez resin (registered trademark) 650 and Sumirez resin 675 (Sumika Chemtex co., ltd. As described above), WS-525 (manufactured by japan PMC corporation), and the like. When the epoxy resin is blended, the amount of the epoxy resin is, for example, 1 to 100 parts by mass, preferably 1 to 50 parts by mass, per 100 parts by mass of the polyvinyl alcohol resin.
The thickness of the adhesive layer formed of the dry curable adhesive is, for example, 0.001 to 5 μm, preferably 0.01 to 2 μm, and more preferably 0.01 to 0.5 μm. If the pressure-sensitive adhesive layer formed of the dry curable pressure-sensitive adhesive is too thick, the appearance tends to be poor.
The active energy ray-curable adhesive may contain a solvent. The active energy ray-curable adhesive is an adhesive that cures upon irradiation with active energy rays. Examples of the active energy ray-curable adhesive include a cationically polymerizable adhesive containing an epoxy compound and a cationic polymerization initiator, a radically polymerizable adhesive containing an acrylic curing component and a radical polymerization initiator, an adhesive containing both a cationically polymerizable curing component such as an epoxy compound and a radically polymerizable curing component such as an acrylic compound and further containing a cationic polymerization initiator and a radical polymerization initiator, and an adhesive which does not contain these polymerization initiators and can be cured by irradiation with an electron beam.
The active energy ray-curable adhesive is preferably a radical-polymerizable active energy ray-curable adhesive containing an acrylic curing component and a photo radical polymerization initiator, or a cation-polymerizable active energy ray-curable adhesive containing an epoxy compound and a photo cation polymerization initiator. Examples of the acrylic acid-based curing component include (meth) acrylic acid esters such as methyl (meth) acrylate and hydroxyethyl (meth) acrylate, and (meth) acrylic acid. The active energy ray-curable adhesive containing an epoxy compound may further contain a compound other than the epoxy compound. Examples of the compound other than the epoxy compound include oxetane compounds and acrylic compounds.
Examples of the photo radical polymerization initiator and the photo cation polymerization initiator include the photo radical polymerization initiator and the photo cation polymerization initiator described above. The content of the radical polymerization initiator and the cationic polymerization initiator is, for example, 0.5 to 20 parts by mass, preferably 1 to 15 parts by mass, per 100 parts by mass of the active energy ray-curable adhesive.
The active energy ray-curable adhesive may further contain an ion scavenger, an antioxidant, a chain transfer agent, an adhesion promoter, a thermoplastic resin, a filler, a flow regulator, a plasticizer, a defoaming agent, and the like.
In the present specification, active energy rays are defined as energy rays capable of decomposing a compound capable of generating an active species to generate an active species. Examples of such active energy rays include visible light, ultraviolet light, infrared light, X-rays, α -rays, β -rays, γ -rays, and electron rays, and ultraviolet light and electron rays are preferable. The irradiation conditions of ultraviolet rays are preferably the same as those of the polymerization of the polymerizable liquid crystal compound described above.
The laminate may include other layers such as a vertical alignment liquid crystal cured film and another alignment liquid crystal cured film.
[ Polarizing plate ]
The polarizing plate according to the present embodiment includes the polarizing film and the optical film according to the above embodiment. The polarizing plate may include a polarizing film and a laminate according to the above embodiment.
(Polarizing film)
The polarizing film is a film having a polarizing function, and examples thereof include a stretched film having a dye having absorption anisotropy adsorbed thereon, a film containing a dye having absorption anisotropy coated thereon, and the like as a polarizer. Examples of the dye having absorption anisotropy include dichromatic dyes.
The polarizer can be manufactured, for example, through the following steps (1) to (4). Thus, a stretched film having adsorbed a dye having absorption anisotropy can be obtained as a polarizer.
Step (1) of uniaxially stretching the polyvinyl alcohol resin film
A step (2) of dyeing the polyvinyl alcohol resin film with a dichroic dye to adsorb the dichroic dye
A step (3) of treating the polyvinyl alcohol resin film having the dichromatic pigment adsorbed thereto with an aqueous boric acid solution
A step (4) of washing with water after the treatment with the aqueous boric acid solution
The polyvinyl alcohol resin can be obtained by saponifying a polyvinyl acetate resin. As the polyvinyl acetate-based resin, a copolymer of vinyl acetate and other monomers copolymerizable therewith may be used in addition to polyvinyl acetate which is a homopolymer of vinyl acetate. Examples of the other monomer copolymerizable with vinyl acetate include unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated sulfonic acids, and acrylamides having an ammonium group.
The saponification degree of the polyvinyl alcohol resin is, for example, 85 to 100 mol%, preferably 98 mol% or more. The polyvinyl alcohol resin may be modified, and for example, polyvinyl formal or polyvinyl acetal modified with aldehydes may be used. The polymerization degree of the polyvinyl alcohol resin is, for example, 1,000 to 10,000, preferably 1,500 to 5,000.
A film made of such a polyvinyl alcohol resin can be used as a polarizing film blank. The method for forming the polyvinyl alcohol resin into a film is not particularly limited, and the film can be formed by a known method. The thickness of the polyvinyl alcohol-based green film may be, for example, 10 to 150 μm.
The uniaxial stretching of the polyvinyl alcohol resin film may be performed before dyeing with a dichroic dye, simultaneously with dyeing, or after dyeing. In the case of uniaxial stretching after dyeing, the uniaxial stretching may be performed before boric acid treatment or may be performed in boric acid treatment. In addition, uniaxial stretching may be performed in a plurality of stages among them. In the case of uniaxial stretching, uniaxial stretching may be performed between rolls having different peripheral speeds, or uniaxial stretching may be performed using a hot roll. The uniaxial stretching may be a dry stretching in which stretching is performed in the atmosphere, or a wet stretching in which stretching is performed in a state in which a polyvinyl alcohol resin film is swollen with a solvent. The stretching ratio is, for example, 3 to 8 times.
Dyeing of the polyvinyl alcohol resin film with the dichromatic pigment can be performed, for example, by immersing the polyvinyl alcohol resin film in an aqueous solution containing the dichromatic pigment.
As the dichroic dye, specifically, iodine or a dichroic organic dye can be used. Examples of the organic dye having dichroism include a dichroism direct dye formed by a disazo compound such as c.i. direct red (DIRECT RE D) 39, and a dichroism direct dye formed by a compound such as trisazo or tetraazo. The polyvinyl alcohol resin film is preferably immersed in water before the dyeing treatment.
When iodine is used as the dichromatic pigment, a method of immersing a polyvinyl alcohol resin film in an aqueous solution containing iodine and potassium iodide to dye the film is generally employed. The iodine content in the aqueous solution is, for example, 0.01 to 1 part by mass per 100 parts by mass of water. The content of potassium iodide is, for example, 0.5 to 20 parts by mass per 100 parts by mass of water. The temperature of the aqueous solution used for dyeing is, for example, 20 to 40 ℃. The immersion time (dyeing time) for immersing in the aqueous solution is, for example, 20 to 1,800 seconds.
On the other hand, in the case of using a dichroic organic dye as a dichroic dye, for example, a method of immersing a polyvinyl alcohol resin film in an aqueous solution containing a water-soluble dichroic dye and dyeing the film can be adopted. The content of the dichroic organic dye in the aqueous solution is, for example, 1×10-4 to 10 parts by mass, preferably 1×10-3 to 1 part by mass, and more preferably 1×10-3～1×10-2 parts by mass, relative to 100 parts by mass of water. The aqueous solution may contain an inorganic salt such as sodium sulfate as a dyeing auxiliary. The temperature of the aqueous solution of the dichroic dye used for dyeing is, for example, 20-80 ℃. The immersion time (dyeing time) for immersing in the aqueous solution is, for example, 10 to 1,800 seconds.
The boric acid treatment after dyeing with a dichroic dye can be performed, for example, by immersing the dyed polyvinyl alcohol resin film in an aqueous boric acid solution. The boric acid content in the aqueous boric acid solution is, for example, 2 to 15 parts by mass, preferably 5 to 12 parts by mass, based on 100 parts by mass of water. When iodine is used as the dichromatic pigment, the aqueous boric acid solution preferably contains potassium iodide, and the content of potassium iodide in this case is, for example, 0.1 to 15 parts by mass, preferably 5 to 12 parts by mass, relative to 100 parts by mass of water. The immersion time in the aqueous boric acid solution is, for example, 60 to 1,200 seconds, preferably 150 to 600 seconds, and more preferably 200 to 400 seconds. The temperature of the boric acid treatment is, for example, 50 ℃ or higher, preferably 50 to 85 ℃, and more preferably 60 to 80 ℃.
The polyvinyl alcohol resin film after boric acid treatment may be subjected to a water washing treatment. The water-washing treatment may be performed, for example, by immersing the boric acid-treated polyvinyl alcohol resin film in water. The temperature of water in the water washing treatment is, for example, 5 to 40 ℃. The immersion time is, for example, 1 to 120 seconds.
The polarizer may be obtained by performing a drying process after washing with water. The drying treatment may be performed using, for example, a hot air dryer or a far infrared heater. The temperature of the drying treatment is, for example, 30 to 100 ℃, preferably 50 to 80 ℃. The drying time is, for example, 60 to 600 seconds, preferably 120 to 600 seconds. Through the drying treatment, the water ratio of the polaroid can be reduced to a practical degree. The water content is, for example, 5 to 20% by weight, preferably 8 to 15% by weight. If the moisture content is less than 5 wt%, the flexibility of the polarizer is impaired, and sometimes the polarizer is damaged or broken after it is dried. In addition, if the moisture content is more than 20 wt%, there is a possibility that the heat stability of the polarizer may be deteriorated.
The thickness of the polarizer is preferably 5-40 μm.
Examples of the film coated with the dye having absorption anisotropy include a film obtained by coating a composition containing a dichroic dye having liquid crystallinity, or a composition containing a dichroic dye and a polymerizable liquid crystal. The film preferably has a protective film on one or both sides thereof. As the protective film, the same substrate as exemplified above can be exemplified.
The thinner the film coated with the pigment having absorption anisotropy is, the more preferable, but if it is too thin, strength tends to be lowered and workability tends to be poor. The thickness of the film is, for example, 20 μm or less, preferably 5 μm or less, and more preferably 0.5 to 3 μm.
The film coated with the dye having absorption anisotropy is specifically a film described in japanese patent application laid-open No. 2012-33249.
The polarizing film may be provided with a transparent protective film. The transparent protective film may be attached to at least one side of the polarizer using an adhesive. As the transparent protective film, a transparent film similar to the base material exemplified above can be preferably used.
The polarizing plate according to the present embodiment can be obtained by laminating the optical film or the laminate according to the above embodiment and the polarizing film via an adhesive layer or the like, for example.
The transmitted light of the polarizing plate according to the present embodiment may be linearly polarized light, circularly polarized light, or elliptically polarized light.
In the case of a polarizing plate, in the case of linearly polarized light, the optical film and the polarizing film according to the above embodiment are preferably laminated such that an angle formed between a slow axis (optical axis) of the optical film and an absorption axis of the polarizing film is 0±5° or 90±5°. In the case of a polarizing plate, the optical film and the polarizing film according to the above embodiment are preferably laminated such that an angle between a slow axis (optical axis) of the optical film and an absorption axis of the polarizing film is 45±5°.
The polarizing plate according to the present embodiment may include, for example, an adhesive layer (sheet) for bonding the polarizing plate to a display element such as an organic EL, a protective film used for protecting the surface of a polarizer or an optical film from damage or contamination, and the like.
[ Image display device ]
The image display device according to the present embodiment includes the polarizing plate according to the above embodiment. The image display device is a device having a display element, and includes a light emitting element or a light emitting device as a light emitting source. The image display device may be, for example, a liquid crystal display device, an organic Electroluminescence (EL) display device, an inorganic Electroluminescence (EL) display device, a touch panel display device, an electron emission display device (for example, an electric field emission display device (FED), a surface electric field emission display device (SED)), an electronic paper (a display device using electronic ink or an electrophoretic element), a plasma display device, a projection display device (for example, a Grating Light Valve (GLV) display device, a display device having a Digital Micromirror Device (DMD)), or a piezoelectric ceramic display.
The liquid crystal display device includes any of a transmissive liquid crystal display device, a semi-transmissive liquid crystal display device, a reflective liquid crystal display device, a direct-view liquid crystal display device, a projection liquid crystal display device, and the like. These display devices may be display devices that display two-dimensional images, or may be stereoscopic display devices that display three-dimensional images. The polarizing plate according to the present embodiment can be suitably used for an organic Electroluminescence (EL) display device and an inorganic Electroluminescence (EL) display device, and the optical film according to the present embodiment can be suitably used for a liquid crystal display device and a touch panel display device. These display devices can exhibit good image display characteristics by including the polarizing plate according to the above embodiment with high reliability.
Examples
Hereinafter, the present disclosure will be described more specifically based on examples and comparative examples, but the present disclosure is not limited to the following examples. Unless otherwise specified, "%" and "parts" in the examples refer to mass% and parts, respectively.
Examples 1 to 4 and comparative example 1
(Preparation of composition for Forming photo-alignment film)
The photo-alignment polymer (weight average molecular weight: 50000, m: n=50:50) having the structure shown below was produced according to the method described in japanese patent laid-open No. 2021-196514. 2 parts of a photo-alignment polymer and 98 parts of cyclopentanone (solvent) were mixed as components to obtain a mixture. The mixture was stirred at 80 ℃ for 1 hour to prepare a composition for forming a photo-alignment film.
Light-oriented material:
[ chemical formula 8]
(Production of polymerizable liquid Crystal Compound)
The polymerizable liquid crystal compound (P1) and the polymerizable liquid crystal compound (P2) each having a structure shown below were prepared. The polymerizable liquid crystal compound (P1) was prepared in the same manner as described in Japanese unexamined patent publication No. 2019-003177. The polymerizable liquid crystal compound (P2) is prepared in the same manner as described in japanese patent application laid-open No. 2009-173893.
Polymerizable liquid crystal compound (P1):
[ chemical formula 9]
Polymerizable liquid crystal compound (P2):
[ chemical formula 10]
1Mg of the polymerizable liquid crystal compound (P1) was dissolved in 10mL of chloroform to obtain a solution. The obtained solution was filled with a measurement sample in a measurement cuvette having an optical path length of 1cm, and the measurement sample was set in an ultraviolet-visible spectrophotometer (manufactured by Shimadzu corporation, "UV-2450"), and the absorption spectrum was measured. The wavelength of the maximum absorbance was read from the obtained absorption spectrum, and as a result, the maximum absorption wavelength λmax was 356nm in the range of 300 to 400 nm.
(Preparation of polymerizable liquid Crystal composition)
The polymerizable liquid crystal compound (P1) and the polymerizable liquid crystal compound (P2) were mixed at a mass ratio (P1: P2) of 90:10 to obtain a mixture. 0.1 part by mass of a leveling agent "BYK-361N" (manufactured by BM Chemie Co., ltd.) and additive A were added to 100 parts by mass of the mixture. The addition amount of the additive a with respect to 100 parts by mass of the mixture was set to the value shown in table 1. The abbreviations in table 1 are as follows.
Compound (A31) A compound (CLogP: 4.352) represented by the above formula (A31)
Compound (A32) A compound (CLogP: 8.496) represented by the above formula (A32)
Compound (C1) A compound (CLogP: 3.8153) represented by the following formula (C1)
[ Chemical formula 11]
N-methyl-2-pyrrolidone (NMP) was further added to the mixture so that the concentration of the solid components (polymerizable liquid crystal compounds (P1), (P2), additive a, and leveling agent) became 13%. The mixture was stirred at a temperature of 80 ℃ for 1 hour, thereby preparing a polymerizable liquid crystal composition.
(Production of laminate)
As a base material, a biaxially stretched polyethylene terephthalate (PET) film (Diafoil mitsubishi resin (ltd)) was prepared. The composition for forming a photo-alignment film is coated on one surface of a substrate by a bar coater. The resulting coating film was dried at 120 ℃ for 2 minutes, and then cooled to room temperature to form a dried film. Then, a polarized ultraviolet light of 100mJ (based on 313 nm) was irradiated using a UV irradiation apparatus (SPOTCURE SP-9, manufactured by USHIO INC.) to obtain a photo-alignment film. The film thickness of the photo-alignment film was 100nm as measured by using an Ellipsometer (ellidometer) M-220 manufactured by Japanese spectroscopic Co.
The obtained photo-alignment film was coated with the polymerizable liquid crystal composition by a bar coater to form a coating film. The coated film was heated and dried at 120 ℃ for 2 minutes, and then cooled to room temperature to obtain a dried film. Subsequently, an ultraviolet light having an exposure of 500mJ/cm2 (based on 365 nm) was irradiated to the above-mentioned dry film under a nitrogen atmosphere using a high-pressure mercury lamp (USHIO INC. Incorporated herein BY reference "Unic ure VB-15201 BY-A"), whereby a horizontally oriented liquid crystal cured film (optical film) was formed. Thus, a laminate formed of the substrate, the photo-alignment film, and the horizontally-aligned liquid crystal cured film was obtained. The polymerizable liquid crystal compound is cured in a state of being oriented in the horizontal direction with respect to the substrate surface. The thickness of the optical film was 2.0 μm as measured by using a laser microscope LEXT OLS4100 manufactured by Olympus corporation.
(Production of test piece 1)
The laminate was cut into 4cm. Times.4 cm pieces. The surface of the laminate on the optical film side was subjected to corona treatment (output: 0.3kW, treatment rate: 3 m/min) 1 time by a corona treatment apparatus (AGF-B10, manufactured by Chun Motor Co., ltd.). The laminate and glass were bonded together with a pressure-sensitive adhesive (manufactured by LINTEC Co., ltd., thickness: 25 μm) interposed therebetween. The lamination was performed so that the corona-treated surface of the laminate faced the glass. The base material (PET film) was peeled off from the laminate to obtain a1 st test piece (layer constitution: glass/adhesive/optical film/photo-alignment film).
(Measurement of in-plane phase Difference value of optical film Using test piece 1)
The in-plane retardation of the optical film was measured using the 1 st test piece. For the measurement, KOBRA-WR manufactured by KORABLE SECURING KORGANING Co., ltd was used. The wavelengths of light were set to 448.2nm, 498.6nm, 548.4nm, 587.3nm, 628.7nm and 748.6nm. Based on the measurement results of these wavelengths, the in-plane phase difference values for the light having wavelengths of 450nm, 550nm and 630nm were obtained by using the Cauchy dispersion formula. The results are shown in Table 1.
(Production of polarizing film)
A polyvinyl alcohol film (average polymerization degree: about 2400, saponification degree: 99.9 mol% or more, thickness: 30 μm) was immersed in pure water at 30 ℃. Next, the polyvinyl alcohol film was immersed in an aqueous solution at 30 ℃ and subjected to iodine dyeing (hereinafter, also referred to as an iodine dyeing step). The aqueous solution used in the iodine staining procedure was a mixture of iodine, potassium iodide and water (mass ratio of iodine to potassium iodide to water was 0.02:2:100).
The polyvinyl alcohol film subjected to the iodine dyeing step was immersed in an aqueous solution at 56.5 ℃ and subjected to boric acid treatment (hereinafter, also referred to as boric acid treatment step). The aqueous solution used in the boric acid treatment step was a mixture of potassium iodide, boric acid and water (the mass ratio of potassium iodide to boric acid to water is 12:5:100).
The polyvinyl alcohol film subjected to the boric acid treatment step was washed with pure water at 8 ℃ and then dried at 65 ℃. Thus, a polarizer in which iodine was adsorbed and oriented on polyvinyl alcohol (thickness after stretching was 12 μm) was obtained. In the iodine dyeing step and the boric acid treatment step, the polyvinyl alcohol film is stretched. The total stretch ratio in this stretching was 5.3 times.
Saponification-treated cellulose triacetate films (KC 4UYTAC, thickness: 40 μm, manufactured by KONICA MINOLTA Co., ltd.) were respectively bonded to both sides of the polarizer with a nip roller via an aqueous adhesive. The resulting laminate was dried at 60℃for 2 minutes while maintaining the tension at 430N/m. A polarizing film having a polarizer and protective films provided on both sides of the polarizer was obtained.
The aqueous adhesive for bonding was prepared by adding 3 parts of carboxyl group-modified polyvinyl alcohol (KURARAY POVAL KL318 manufactured by KURARAY corporation) and 1.5 parts of water-soluble polyamide epoxy resin (Sumirez resin (registered trademark) 650, manufactured by Tian Gang chemical industry co., ltd. In water, as an aqueous solution having a solid content concentration of 30%) to 100 parts of water.
For the polarizer, measurement of optical characteristics was performed using a spectrophotometer (V7100, manufactured by japan spectroscopy). The visibility correction monomer transmittance of the polarizer was 42.1%, the visibility correction polarization was 99.996%, the monomer hue a* was-1.1, and the monomer hue b* was 3.7.
(Production of test piece 2)
The 1 st test piece was produced in the same manner as the 1 st test piece. The surface of the 1 st test piece on the photo-alignment film side was subjected to corona treatment (output: 0.3kW, treatment rate: 3 m/min) 1 time using a corona treatment apparatus (AGF-B10, manufactured by Chun Motor Co., ltd.). The polarizing film and the 1 st test piece were bonded via a pressure-sensitive adhesive (manufactured by LINTEC Co., ltd., thickness: 25 μm). The test piece 1 was bonded so that the corona-treated surface of the test piece faced the protective film on one side of the polarizing film and the angle between the light absorption axis direction of the polarizer and the slow axis direction of the laminate was 45 °. Thus, a2 nd test piece (layer constitution: glass/adhesive/optical film/photo-alignment film/triacetylcellulose film/polarizer/triacetylcellulose film) in which a polarizing plate was bonded to glass was obtained.
(Exposure treatment)
The 2 nd test piece was housed in a chamber of a light resistance tester (SANTEST XLS +, manufactured by ATLAS). The 2 nd test piece was stored so that the polarizing plate side became the xenon lamp side. While the 2 nd test piece was allowed to stand for 300 hours by irradiation with xenon lamp light (illuminance: 267mW/m2). The 2 nd test piece was taken out of the chamber and allowed to stand at 25℃under 55% humidity for 1 hour.
(Measurement of in-plane phase Difference value of optical film Using test piece 2)
The in-plane retardation of the optical film was measured in the same manner as in the measurement of the in-plane retardation of the optical film using the 1 st test piece except that the 2 nd test piece before the exposure treatment was used instead of the 1 st test piece.
The in-plane retardation of the optical film was measured in the same manner as in the case of (measurement of in-plane retardation of the optical film using the 1 st test piece) except that the 2 nd test piece after the exposure treatment was used instead of the 1 st test piece.
The change amount (Δre (450)/Re (550)) of the wavelength dispersion value (Re (450)/Re (550)) of the circularly polarizing plate with glass before and after the exposure treatment was calculated, and the change amount was evaluated according to the following criteria, and the results are shown in table 1.
(Reference)
A is less than 0.02
B is more than 0.02 and less than 0.03
C is more than 0.03
The amount of change (Δre (550)) of Re (550) of the glass-equipped circularly polarizing plate before and after the exposure treatment was calculated. The amount of change was evaluated according to the following criteria. The results are shown in Table 1.
(Reference)
A is less than 4nm
B is more than 4nm and less than 7nm
C is above 7nm
(Determination of the content of Compound (A))
The content of the compound (a) per unit volume of the optical film was measured. Specifically, the 1 st test piece was scraped from the photo-alignment film side by a spatula, and about 3 to 4mg of the optical film was collected. The collected optical film was added to 2mL of THF (tetrahydrofuran) and left to stand for 24 hours. Thus, an extract solution in which the target component is extracted into THF is obtained. The extract was subjected to HPLC measurement under the following conditions, whereby quantitative analysis of the compound (a) was performed. From the result of the quantitative analysis, the content of the compound (a) per unit volume of the optical film was calculated. The results are shown in Table 1.
< Conditions for HPLC measurement >
Measurement device HPLC LC-10AT (manufactured by Shimadzu corporation)
Column L-column ODS (length: 105mm, inner diameter: 3mm, particle size: 3 μm)
Flow rate 0.5 mL/min
Sample injection amount 5. Mu.L
Detection wavelength of 254nm, 350nm
Mobile phase a water with 0.1% TFA (trifluoroacetic acid ) added
Mobile phase B acetonitrile
Stabilization time 15 min
Gradient conditions of 70% -100% mobile phase B for 30min, and then 100% mobile phase B for 30min
TABLE 1