Embodiment
The result that present inventors attentively study to achieve these goals is characterised in that use is that thermal endurance black pigment below the 5 μ m is dispersed in the slurry in the solvent with maximum particle diameter.
Thus, Photocurable composition of the present invention can be made the paste that does not have the secondary agglutinator easily.Its result can provide the PDP that forms high meticulous telegraph circuit and black matrix".
On the other hand, contain the Photocurable composition of filler such as thermal endurance black pigment, do not have the shortcoming that stabilizer at room temperature may tackify if exist.Therefore, for the polymerization that suppresses photopolymerization monomer be considered to because the gelation of the Photocurable composition that the carboxyl reaction in thermal endurance black pigment and the organic bond causes can be used phosphate as stabilizer at present.Yet, in Photocurable composition of the present invention, if use phosphate as stabilizer, the problem of existence be cause in the slurry the sedimentation of thermal endurance black pigment, cause the powder aggegation easily, and then bring harmful effect for the storage stability of slurry.
To this, present inventors make further research again, found that by cooperating the organic acid as stabilizer, preferred organic acid and thermal polymerization inhibitor, can be provided in storage stability under the room temperature also extremely good, also can fully adapt to the Photocurable composition of the property produced in batches.
In addition according to Photocurable composition of the present invention, if use the cobaltosic oxide black particles as above-mentioned thermal endurance black pigment, it is fine and close that the black thin film that forms becomes, even film also can present enough black, its result can obtain not damaging the adaptation good with respect to substrate, clarity, agglutinating property in each operation of drying, exposure, development, sintering, can obtain satisfying simultaneously the pattern of sufficient interlayer conductivity (interlayer conduction of the white layer of transparency electrode and bus electrode) and blackness behind sintering.
Thereby, if use the black layer material of such Photocurable composition as the bus electrode of the white black double-layer structure that forms on the PDP front substrate, be clipped in sandwich between transparency electrode such as ITO or nesa coating and the white layer because bus electrode has black layer, therefore can fully satisfy the interlayer conduction of transparency electrode and white layer and the black when the picture side is observed simultaneously.
And, Photocurable composition of the present invention, because storage stability thickness good and that use is thin can obtain enough contrasts as mentioned above, therefore batch process and the cost degradation for PDP is exceedingly useful.
Be illustrated particularly at Photocurable composition of the present invention below.
At first, be that the slurry (A) that thermal endurance black pigment below the 5 μ m is dispersed in the solvent can be according at present known method by making the thermal endurance black pigment be evenly dispersed in that modulation forms in the solvent with maximum particle diameter.For example, using mixer such as ball mill to make solvent, dispersant and thermal endurance black pigment mix fully disperses modulation to form.
Here, as stable on heating black pigment,, therefore can use inorganic pigment with tone stability under the high temperature owing in the substrate manufacture operation of PDP, follow 500～600 ℃ high temperature sintering.Oxide such as Cr, Co, Cu, Ni, Fe, Mn and composite oxides etc. are arranged particularly, but be not limited to these, these can use more than 2 kinds alone or in combination.Particularly in the present invention, copper-chromium is that black composite oxide, copper-iron are black composite oxide, cobaltosic oxide etc., and therefore densification and excellent color tone because the black thin film that forms behind sintering becomes are fit to use.
It is below the 2 μ m that this thermal endurance black pigment preferably uses average grain diameter, more preferably the following particulate of the above 1 μ m of 0.01 μ m.Its reason be because, if average grain diameter is below the 2 μ m, ground forms fine and close sintered film even a small amount of interpolation also can not can damage adaptation etc., and the resin combination that can provide lower floor's (black layer) electrode of satisfying sufficient interlayer conductivity (interlayer conduction of the white layer of transparency electrode and bus electrode) and black simultaneously to use.On the other hand, if the average grain diameter of thermal endurance black pigment greater than 2 μ m, the compactness variation of sintered film, the degree of blackness of the lower electrode film of formation reduces easily.In addition, if less than 0.01 μ m,, therefore be not suitable for because covering power reduces, manifests transparent feel.
In addition, the thermal endurance black pigment preferably uses specific area at 1.0～20m2Cobaltosic oxide particulate in the/g scope.Its reason be because, if the not enough 1.0m of its specific area2/ g, the precision of the circuit pattern that forms by exposing reduces, and obtains the linearity at line edge or the sintered film of enough blackness and becomes difficult.On the other hand, if surpass 20m2/ g, the surface area of particle becomes excessive, and lower floor's development relative deficiency takes place when developing easily.
The combined amount of the thermal endurance black pigment in this slurry, suiting to be adjusted into respect to 100 mass parts organic bonds (B) is the scope of 1～120 mass parts, preferred 30～100 mass parts.Its reason is because if the use level of thermal endurance black pigment is also lacked than above-mentioned scope, then can not get enough blackness behind sintering, on the other hand, if combined amount surpasses above-mentioned scope, the permeability variation of light, clarity reduce, cost uprises in addition, is unfavorable.
The solvent that uses in the above-mentioned slurry can be selected arbitrarily, but in order to prevent the solvent upset, solvent and the kind used in hope and the paste are same.
In addition, the concentration of the solid constituent in the slurry can be selected arbitrarily, if but consider operability etc., be preferably 50～80 quality %.That is, to be preferably with respect to 100 mass parts slurries be the ratio of 20～50 mass parts to the use level of solvent.
In addition, the dispersant that uses in the above-mentioned slurry, as long as can disperse the thermal endurance black pigment equably, limit especially, for example can enumerate the chemical Off ロ-macromolecule dispersing agents such as レ Application made of マ リ ア リ system series and common prosperity society that Japanese grease is made.
The combined amount of this dispersant, being suitably with respect to 100 mass parts thermal endurance black pigments is 1～20 mass parts.Under the situation that the use level of this dispersant is lacked than above-mentioned scope, can not obtain sufficient dispersion effect, on the other hand, add and also can not get better dispersion effect even surpass above-mentioned scope volume.
Secondly, as above-mentioned organic bond (B), can use the resin that contains carboxyl, itself have a photoresist of the carboxyl that contains the ethene unsaturated double-bond and have any in the resin of the carboxyl that does not contain the ethene unsaturated double-bond specifically.As the resin that can be fit to use (in oligomer and the polymer any all can), can be listed below.
(1) by making unsaturated carboxylic acid (a) and contain the resin that contains carboxyl that compound (b) copolymerization of unsaturated double-bond obtains
(2) by at unsaturated carboxylic acid (a) with contain the photoresist that contains carboxyl that addition ethene unsaturated group obtains as side group in the copolymer of compound (b) of unsaturated double-bond
(3) feasible copolymer and the secondary hydroxyl of unsaturated carboxylic acid (a) reaction generation and the photoresist that contains carboxyl that multi-anhydride (d) reaction obtains that contains the compound (c) of epoxy radicals and unsaturated double-bond and contain the compound (b) of unsaturated double-bond
(4) make the copolymer contain the acid anhydrides (e) of unsaturated double-bond and to contain the compound (b) of unsaturated double-bond react the photoresist that contains carboxyl that obtains with the compound (f) that contains hydroxyl and unsaturated double-bond
(5) secondary hydroxyl and the multi-anhydride (d) that makes multi-functional epoxy compound (g) and unsaturated monocarboxylic (h) reaction generate reacts the photoresist that contains carboxyl that obtains
(6) make and to react the resin that contains carboxyl that obtains with multi-anhydride (d) by the secondary hydroxyl that contains 1 carboxyl in epoxy radicals and 1 molecule in the copolymer of the compound (b) contain unsaturated double-bond and (methyl) glycidyl acrylate, do not contain organic acid (i) the reaction generation of ethene unsaturated double-bond
(7) make the polymer (j) that contains hydroxyl react the resin that contains carboxyl that obtains with multi-anhydride (d)
(8) make the polymer (j) that contains hydroxyl react the resin that contains carboxyl that obtains, react the photoresist that contains carboxyl that obtains with the compound that contains epoxy radicals and unsaturated double-bond (c) with multi-anhydride (d)
The above-mentioned resin that contains the photoresist of carboxyl and contain carboxyl can be used alone or as a mixture, but preferably cooperates with the ratio of 10～80 quality % that add up to total composition in either case.When the use level of these polymer was more very few than above-mentioned scope, it is inhomogeneous that the distribution of the above-mentioned resin in the film of formation becomes easily, is difficult to obtain the enough photo-curables and the photocuring degree of depth, becomes difficult by selecting exposure, development to form pattern.On the other hand, if more too much than above-mentioned scope, fold and live width that pattern takes place during owing to sintering are easily shunk, and are unfavorable therefore.
In addition, as the above-mentioned resin that contains the photoresist of carboxyl and contain carboxyl, suitable use separately weight average molecular weight be 1000～100000, preferred 5000～70000 and acid number be 50～250mgKOH/g, and be 350～2000, preferred 400～1500 resin for its pair of the photoresist key equivalent that contains carboxyl.Being lower than at the molecular weight of above-mentioned resin under 1000 the situation, will the adaptation of film bringing harmful effect when developing, on the other hand, being higher than under 100000 the situation, because poor visualization takes place easily, is unfavorable therefore.In addition, be lower than at acid number under the situation of 50mgKOH/g, dissolubility with respect to alkaline aqueous solution is insufficient, poor visualization takes place easily, be higher than under the situation of 250mgKOH/g on the other hand, because the dissolving of the deterioration and the photocuring part (exposed portion) of film adaptation takes place when developing, be unfavorable therefore.In addition, for the situation of the photoresist that contains carboxyl, if two key equivalents of photoresist are less than 350, if easy residual residue when sintering then is on the other hand greater than 2000, because the operation degree of freedom when developing is narrow, and needing high exposure when photocuring, is unfavorable therefore.
Secondly, the photopolymerization monomer in the Photocurable composition of the present invention (C) uses for the photo-curable and the raising development that promote composition.As this photopolymerization monomer (C), specifiable is acrylic acid 2-hydroxyl ethyl ester for example, acrylic acid 2-hydroxypropyl acrylate, diacrylate diethylene glycol (DEG) ester, the diacrylate triethyleneglycol ester, polyethyleneglycol diacrylate, urethane diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetracrylate, the triacrylate of trimethylolpropane oxirane modification, the triacrylate of trimethylolpropane epoxy pronane modification, five acrylic acid dipentaerythritol ester, six acrylic acid dipentaerythritol ester and corresponding to each methyl acrylic ester of aforesaid propylene acid esters; The list of polyacid such as phthalic acid, adipic acid, maleic acid, furoate clothing, butanedioic acid, trimellitic acid, terephthalic acids and hydroxyalkyl (methyl) acrylate-, two-, three-or its above polyester etc., but be not limited to specific these, these esters can separately or mix more than 2 kinds and use in addition.In these photopolymerization monomers, contain the polyfunctional monomer of 2 above acryloyl groups or methacryl in preferred 1 molecule.
The use level of this photopolymerization monomer (C), being suitably for respect to the above-mentioned organic bond of 100 mass parts (contain the photoresist of carboxyl and/or contain the resin of carboxyl) is 20～100 mass parts (B).The use level of photopolymerization monomer (C) than above-mentioned scope after a little while, the sufficient photo-curable of composition is difficult to obtain, become when excessive if surpass above-mentioned scope on the other hand, become early, therefore take place to solidify inhomogeneous easily owing to compare the photocuring at surperficial position with the position, deep of film.
Secondly, as the Photoepolymerizationinitiater initiater in the Photocurable composition of the present invention (D), specifiable is for example benzoin and benzoin alkyl ethers such as benzoin, benzoin methyl ether, benzoin ether, benzoin isopropyl ether; Acetophenone, 2,2-dimethoxy-2-phenyl acetophenone, 2,2-diethoxy-2-phenyl acetophenone, 1, acetophenones such as 1-dichloroacetophenone; 2-methyl isophthalic acid-[4-(methyl mercapto) phenyl]-2-morpholinyl third-1-ketone, 2-benzyl-2-dimethylamino-1-(4-morpholinyl phenyl)-Ding-aminoacetophenone classes such as 1-ketone; Anthraquinone classes such as 2-methylanthraquinone, 2-EAQ, 2-tert-butyl group anthraquinone, 1-chloroanthraquinone; 2,4-dimethyl thioxanthones, 2,4-diethyl thioxanthone, 2-clopenthixal ketone, 2, thioxanthene ketones such as 4-diisopropyl thioxanthones; Ketal classes such as acetophenone dimethyl ketal, benzyl dimethyl ketal; Benzophenones such as benzophenone; Perhaps xanthones; (2,6-dimethoxy benzoyl)-2,4,4-amyl group phosphine oxide, two (2,4, the 6-trimethylbenzoyl)-phenyl phosphine oxide, 2,4,6-trimethylbenzoyl diphenyl phosphine oxide, ethyl-2,4, phosphinoxides such as 6-trimethylbenzoyl phenyl phosphine oxide; Various peroxides etc., these known habitual Photoepolymerizationinitiater initiaters can separately or mix use more than 2 kinds.The cooperation ratio of these Photoepolymerizationinitiater initiaters (D) is suitably for respect to the above-mentioned organic bond of 100 mass parts (contain the photoresist of carboxyl and/or contain the resin of carboxyl) and is (B) 1～30 mass parts, preferred 5～20 mass parts.
In addition, above-mentioned Photoepolymerizationinitiater initiater (D) can mix N, N-dimethylamino ethyl benzoate, N, using more than a kind or 2 kinds in the light sensitizer of tertiary amines such as N-dimethylamino benzoic acid isopentyl ester, amyl group-4-dimethylaminobenzoic acid ester, triethylamine, triethanolamine.
In addition, under the situation that requires the darker photocuring degree of depth, may be combined in the visibility region two luxuriant titanium class Photoepolymerizationinitiater initiaters such as Irgacure-784 that the Ciba Speciality Chemicals society of causing radical polymerization makes as required and use as the leuco dye of auxiliary curing agent.
In the present invention, in Photocurable composition, mix under the situation of excessive inorganic filler and glass powder, exist the storage stability of the composition that obtains poor, because gelation and mobile reduction cause being coated with the tendency of operability variation.Thereby, in composition of the present invention, in order to improve the storage stability of composition, preferred add for as the metal or the oxide powder complexing of the composition of inorganic filler and glass powder or form salt etc. effectively certain compound be that organic acid (E) is as stabilizer.As this organic acid (E), specifiablely be acid such as malonic acid, adipic acid, formic acid, acetic acid, acetoacetic acid, citric acid, stearic acid, maleic acid, fumaric acid, phthalic acid.These acid can separately or mix more than 2 kinds to be used.Such organic acid is preferably being that the ratio of 0.1～10 mass parts is added with respect to the above-mentioned glass powder of 100 mass parts and inorganic fine particles.
On the other hand, the past is used the stabilizer of phosphate as cobalt always, is not very effective for cobaltosic oxide still.
In addition on the one hand, in Photocurable composition of the present invention, cooperate under the situation of photopolymerization monomer, exist the storage stability of the composition that obtains poor, because gelation and mobile reduction cause being coated with the tendency of operability variation.Therefore, in composition of the present invention,, preferably add the thermal polymerization inhibitor (F) of photopolymerization monomer in order to improve the storage stability of composition.As this thermal polymerization inhibitor (F), specifiable is phenthazine, quinhydrones, N-nonox, chloranil, pyrogallol, benzoquinones, tert-butyl catechol etc., and these can separately or mix use more than 2 kinds.Such thermal polymerization inhibitor (F) is preferably with respect to the above-mentioned organic bond of 100 mass parts to be the ratio interpolation of 0.01～1 mass parts.
Also have, Photocurable composition of the present invention, can cooperate softening point as required with the ratio of the amount of not damaging Photocurable composition characteristic of the present invention is 400～600 ℃ glass powder, electroconductive powder.
In order to improve the adaptation of conductor circuit behind the sintering, glass powder can be with respect to 100 mass parts cobaltosic oxide (Co3O4) thermal endurance black pigment such as black particles is that the ratio that 200 mass parts are following, preferred 150 mass parts are following is added.As this glass powder, preferred glass inversion point (Tg) is that 300～500 ℃, glass softening point (Ts) are 400～600 ℃ glass powder.In addition, from the clarity aspect, preferably using average grain diameter is the glass powder that 20 μ m are following, preferred 5 μ m are following.
By add above-mentioned glass powder in Photocurable composition, the film behind the exposure imaging can be easy to sintering below 600 ℃.But, in composition of the present invention, used the good organic bond of flammability, make that removing adhesive before the glass powder fusion is over, if but the softening point of glass powder is lower than 400 ℃, under than this also low temperature fusion takes place, wrapping organic bond easily, because remaining organic bond decomposes, bubbling easily in the composition, is unfavorable therefore.
As glass powder, be fit to use the amorphism frit as main component such as lead oxide, bismuth oxide or zinc oxide.
In the present invention, as the diluent that is used for the paste composition livering or be used for the diluent that the corresponding viscosity of various painting process is adjusted, can cooperate the organic solvent of Sq.Concrete specifiable is ketones such as methyl ethyl ketone, cyclohexanone; Toluene, dimethylbenzene, durol etc. are aromatic hydrocarbon based; Glycol ethers such as cellosolve, methyl cellosolve, carbitol, methyl carbitol, butyl carbitol, Glycol Monomethyl ether, DPG monomethyl ether, DPG monoethyl ether, triethylene glycol monoethyl ether; Acetates such as ethyl acetate, butyl acetate, cellosolve acetate, butylacetic acid cellosolve, carbitol acetate, butyl carbitol acetate, Glycol Monomethyl ether acetic acid esters; Alcohols such as ethanol, propyl alcohol, ethylene glycol, propylene glycol, terpineol; Aliphatic hydrocarbon such as octane, decane; Petroleum-type solvents such as benzinum, naphtha, hydrotreated naphtha, solvent naphtha, these solvents can separately or mix use more than 2 kinds.
Photocurable composition of the present invention in addition as required can also hybrid silicone class, propylene class froth breaking levelling agent, be used to improve other additives such as silane coupler of film adaptation.Moreover, in the time of can also adding known habitual antioxidant and sintering as required as with particulates such as the metal oxide of substrate binding constituents, Si oxide, boron oxide compound.
Photocurable composition of the present invention, forming under the situation of film like in advance, can be on substrate lamination, but under the situation of paste shape composition, using the coating process that it is suitable that silk screen print method, rod are coated with method, knife coating etc. for example to become at substrate on the glass plate of PDP front substrate is coated with, then in order to obtain dry to touch, use heated air circulation type drying oven, far infrared drying stove etc. to descend dry about 5～40 minutes at about 60～120 ℃, make organic solvent evaporation, obtain tack-free filming.Then, the exposure of selecting, development, sintering, the telegraph circuit of formation predetermined pattern.
As exposure process, can use the contact exposure and the noncontact exposure of the negative mask that contains the regulation exposing patterns.As exposure light source, use Halogen lamp LED, high-pressure mercury-vapor lamp, laser, metal halide lamp, black light lamp, electrodeless lamp etc.Exposure is preferably 50～1000mJ/cm2About.
As developing procedure, can use spray-on process, infusion process etc.As developer solution, be fit to use amine aqueous solutions such as the metal alkaline aqueous solution such as NaOH, potassium hydroxide, sodium carbonate, potash, sodium metasilicate and monoethanolamine, diethanol amine, triethanolamine, rare alkaline aqueous solution of the following concentration of particularly about 1.5 quality %, as long as but can make and contain the carboxyl saponification of carboxy resin in the composition and remove uncured portion (unexposed portion) just passable, be not limited to above-mentioned developer solution.In addition, in order to remove the unwanted developer solution in back that develops, preferably wash or the acid neutralization.
In sintering circuit, the substrate after the development carries out about 400～600 ℃ heat treated under air or nitrogen atmosphere, form desirable black pattern.Also have, programming rate at this moment preferably sets below 20 ℃/minute.
Embodiment
Below with reference to embodiment and comparative example the present invention is specifically described, but obviously the present invention is not limited to the following examples.Also have, " part " of appearance and " % " all are quality criteria unless otherwise specified.(synthesis example 1)
In the flask of being furnished with thermometer, blender, dropping funel and reflux condenser, with 0.76: 0.24 mol ratio pack into methyl methacrylate and methacrylic acid, add the DPG monomethyl ether as solvent, azodiisobutyronitrile as catalyst, nitrogen atmosphere, 80 ℃ of following stirrings 2～6 hours, obtain resin solution.Cool off this resin solution, use methylnaphthohydroquinone as polymerization inhibitor, Xiuization 4-butyl-phosphonium as catalyst, under the condition of 95～105 ℃ and 16 hours, make that glycidyl methacrylate is the addition mol ratio generation addition reaction of 0.12 mole ratio with the carboxyl with respect to 1 mole of above-mentioned resin, take out the cooling back, generates organic bond A.The resin of this organic bond A, weight average molecular weight is about 10000, and acid number is 59mgKOH/g, and two key equivalents are 950.Also have, the mensuration of the weight average molecular weight of the copolymer resins that obtains is by with (strain) Shimadzu Seisakusho Ltd. system Port Application プ LC-6AD and clear and electrician's (strain) makes カ ラ system Shodex (registered trade mark) KF-804, these three high-speed liquid chromatographies that connect into of KF-803, KF-802 are measured.(synthesis example 2)
Except packing into methyl methacrylate and methacrylic acid than to be made as mol ratio be 0.87: 0.13 and do not make the glycidyl methacrylate generation addition reaction, with the above-mentioned synthesis example 1 same organic bond B that generates.The resin of this organic bond B, weight average molecular weight is about 10000, and acid number is 74mgKOH/g.
Use the organic bond A or the B that obtain thus,, after the blender stirring, undertaken pasteization by the grinding of 3 bench roller formula grinders according to ratio of components complexing compositions as follows.Grinding condition is to obtain the 1kg sample size at room temperature 30 minutes.
Also have, in this embodiment, with maximum particle diameter is that thermal endurance black pigment below the 5 μ m evenly is dispersed to the slurry (A) in the solvent, be to be 10 parts dispersant by using with respect to 100 parts of black particle, make that maximum particle diameter is that the 5 μ m concentration of black particle in TPM (tripropylene glycol monomethyl ether) following, that average grain diameter is the cobaltosic oxide of 0.2 μ m is 70%, adopt ball mill evenly to disperse modulation to form (solvent strength of slurry second month in a season: 100 parts of slurries are had 23 parts of solvents).Wherein, as dispersant, the macromolecule dispersing agent that uses Japanese grease to make: AKM-0531 for slurry (A-1), uses the macromolecule dispersing agent of the chemical manufacturing of common prosperity society: being of DOPA-15B slurry (A-2).
In addition, as glass powder, use 60%PbO, 20%B2O3, 15%SiO2, 5%Al2O3Pulverize and make thermalexpansioncoefficient300=70 * 10-7/ ℃, glass transition point is that 445 ℃, average grain diameter are the glass powder of 1.6 μ m.The conductive paste of white layer electrode (upper strata) usefulness;
100.0 parts of organic bond A
50.0 parts of pentaerythritol triacrylates
5.0 parts of 2-benzyl-2-dimethylamino-1-(4-morpholinyl phenyl) fourths-1-ketone
80.0 parts of tripropylene glycol monomethyl ethers
450.0 parts in silver powder
22.0 parts of glass powders
The paste of 1.0 parts of black layer electrode (lower floor) usefulness of phosphate; (composition example 1)
100.0 parts of organic bond B
50.0 parts of pentaerythritol triacrylates
5.0 parts of 2-benzyl-2-dimethylamino-1-(4-morpholinyl phenyl) fourths-1-ketone
40.0 parts of tripropylene glycol monomethyl ethers
50.0 parts in slurry (A-1) (composition example 2)
100.0 parts of organic bond B
50.0 parts of pentaerythritol triacrylates
7.5 parts of 2-methyl isophthalic acids-[4-(methyl mercapto) phenyl]-2-morpholinyl third-1-ketone
2,1.0 parts of 4-diethyl thioxanthones
40.0 parts of tripropylene glycol monomethyl ethers
50.0 parts in slurry (A-1) (composition example 3)
100.0 parts of organic bond B
50.0 parts of pentaerythritol triacrylates
7.5 parts of 2-methyl isophthalic acids-[4-(methyl mercapto) phenyl]-2-morpholinyl third-1-ketone
2,1.0 parts of 4-diethyl thioxanthones
40.0 parts of tripropylene glycol monomethyl ethers
50.0 parts in slurry (A-1)
1.0 parts of malonic acid (composition example 4)
100.0 parts of organic bond B
50.0 parts of pentaerythritol triacrylates
7.5 parts of 2-methyl isophthalic acids-[4-(methyl mercapto) phenyl]-2-morpholinyl third-1-ketone
2,1.0 parts of 4-diethyl thioxanthones
40.0 parts of tripropylene glycol monomethyl ethers
50.0 parts in slurry (A-1)
1.0 parts of malonic acid
0.1 part of phenthazine (composition example 5)
100.0 parts of organic bond B
50.0 parts of pentaerythritol triacrylates
7.5 parts of 2-methyl isophthalic acids-[4-(methyl mercapto) phenyl]-2-morpholinyl third-1-ketone
2,1.0 parts of 4-diethyl thioxanthones
40.0 parts of tripropylene glycol monomethyl ethers
50.0 parts in slurry (A-2)
1.0 parts of malonic acid
0.1 part of phenthazine (comparative composition example 1)
100.0 parts of organic bond B
50.0 parts of pentaerythritol triacrylates
5.0 parts of 2-benzyl-2-dimethylamino-1-(4-morpholinyl phenyl) fourths-1-ketone
80.0 parts of tripropylene glycol monomethyl ethers
Cobaltosic oxide (Co3O4)
Average grain diameter: 35.0 parts of 0.2 μ m
1.0 parts of phosphates
For the various pastes in composition example 1～5 that obtains thus and the comparative composition example 1, estimate maximum particle diameter, the wire shaped behind the sintering, the stability of paste, resistivity, interlayer conduction, the L of cobaltosic oxide*Value.Its evaluation method is as described below.(maximum particle diameter of cobaltosic oxide)
The fineness gauge that the paste of black layer electrode (lower floor) usefulness that obtains at combinations thereof, use can 2.5 μ m units be measured 5～25 μ m is measured the maximum particle diameter of cobaltosic oxide.(stability of paste)
The various pastes of 300g composition example 3,4, comparative composition example 1 are put into closed container respectively, placed 1 month down, estimate the tackify rate (%) of paste at 40 ℃.(wire shaped behind the sintering)
On the glass substrate that has the ITO film, use 300 purpose polyester screen to be coated with to estimate the paste of usefulness comprehensively, then, use the heated air circulation type drying oven 90 ℃ dry 20 minutes down, form the dry to touch good film.Secondly, on this film, use the 300 purpose polyester screen conductivity paste of the white layer of coating electrode (upper strata) usefulness comprehensively, then, use the heated air circulation type drying oven 90 ℃ dry 20 minutes down, form the good white black two-layer film of dry to touch.Then, use metal halide lamp as light source, line/egative film of μ m carries out pattern exposure at interval=50/100 in use, makes that the accumulation light quantity on the composition is 300mJ/cm2, follow 0.5wt%Na at 25 ℃2CO3The aqueous solution develops, washing, and the speed with 5 ℃/minute heats up under air atmosphere at last, at 30 minutes pattern-making sintered base plates of 550 ℃ of following sintering.Then, same with the situation that above-mentioned resistivity is estimated except sintering, make the pattern sintered base plate.
At the sintered base plate that obtains thus, use the microscopic examination pattern, have or not the irregular corrugationless etc. that departs from, has on the evaluation line.(resistivity, interlayer conduction)
Except using the negative mask exposure of pattern dimension, similarly make the test substrate with the evaluation of above-mentioned (wire shaped behind the sintering) as 0.4cm * 10cm.At the test substrate that obtains thus, use milliohmmeter to measure the resistance value of sintered film, then use サ-Off コ--(surface coated device) to measure the thickness of sintered film, calculate the resistivity of sintered film.
In addition, place tester on the white layer electrode (upper strata) of sintered film and ITO film, carry out the affirmation of conducting, the situation of conducting is designated as zero, not the situation of conducting be designated as *.(L*Value)
Except using the negative mask exposure of pattern dimension, similarly make the test substrate with the evaluation of above-mentioned (wire shaped behind the sintering) as 3cm * 10cm.At the test substrate that obtains thus, use color colorimeter (ミ ノ Le カ メ ラ (strain) manufacturing, CR-221) to measure L according to JIS-Z-8729*a*b*Chromatic value is L with the index of representing brightness*Value is estimated as the index of degree of blackness.This L*It is good more to be worth more little degree of blackness.
These evaluation results are as shown in table 1.
Table 1
| The composition example | Comparative composition example 1 |
| ??1 | ??2 | ????3 | ????4 | ????5 |
| Maximum particle diameter (μ m) | Below 5 | Below 5 | Below 5 | Below 5 | Below 5 | ????12.5 |
| The tackify rate (%) of paste | ??- | ??- | ????10 | ????5 | ????5 | ????10 |
| Wire shaped behind the sintering | Do not have | Do not have | Do not have | Do not have | Do not have | Have |
| Layer is asked conducting | ??○ | ??○ | ????○ | ????○ | ????○ | ????○ |
| Resistivity (* 10-6Ωcm) | ??3.2 | ??3.3 | ????3.2 | ????3.2 | ????3.2 | ????3.4 |
| ?L*Value | ??8.1 | ??8.4 | ????8.3 | ????8.2 | ????8.1 | ????9.7 |
Can obviously learn the little and even dispersion of the maximum particle diameter of the cobaltosic oxide in the Photocurable composition paste of the present invention from the result shown in this table 1.
Can learn, on the wire shaped behind the sintering, do not have irregularly to depart from fold etc. in addition, can form high meticulous telegraph circuit according to Photocurable composition of the present invention.
Also have, can learn Photocurable composition of the present invention, not only can form high meticulous sintering pattern, even also can form the good black layer electrode (lower floor) that behind sintering, also can satisfy enough interlayer conductions and blackness simultaneously of storage stability.Can learn that particularly storage stability is good under the situation of mixed organic acid and polymerization inhibitor.
Also have, no problem at the adaptation behind the paste evaluation sintering of above-mentioned evaluation usefulness.This adaptation is that cellophane tape is peeled off, whether figuratum peeling off estimated by using.
As mentioned above, Photocurable composition according to the present invention can not can cause thermal endurance black pigment secondary aggegation ground carry out pasteization, and storage stability is good, in each operation of drying, exposure, development, sintering, can not damage the adaptation good, clarity, agglutinating property, even behind sintering, can form sintered film with enough blackness with respect to substrate yet.
And, according to Photocurable composition of the present invention, can be provided in black layer (lower floor) telegraph circuit that can satisfy enough interlayer conductivity (interlayer conduction of the white layer of transparency electrode and bus electrode) and blackness in the bus electrode that forms white black double-layer structure on the front substrate of PDP simultaneously etc., the meticulous black pattern of height.
Such Photocurable composition of the present invention, owing to improve the productivity ratio of paste, storage stability is good and use thin thickness can obtain enough contrasts, therefore a large amount of productions and the cost degradation for PDP is exceedingly useful.