EP1379445B1 - Water soluble containers comprising at least two compartments - Google Patents

Abstract

A process for producing a water-soluble article comprising a first compartment containing a first composition and a second compartment comprising a second composition, which process comprises: a. producing a first compartment; b. filling the first compartment with the first composition; and either c. providing a sealing film comprising the second composition and sealing the first compartment with the sealing film; or d. sealing the first compartment with a sealing film; producing a second compartment from the of sealing film of the first compartment; filing the second compartment with the second composition; and sealing the second compartment with a second sealing film. (same again)

Description

• The present invention relates to a water-soluble containerand to a process for preparing such a container.
• It is known to package chemical compositions, particularlythose which may be of a hazardous or irritant nature, infilms, particularly water soluble films. Such containers cansimply be added to water in order to dissolve or disperse thecontents of the container into the water.
• For example, WO 89/12587 discloses a package which comprisesan envelope of a water soluble material which comprises aflexible wall and a water-soluble heat seal. The package maycontain an organic liquid comprising, for example, apesticide, fungicide, insecticide or herbicide.
• WO 92/17382 discloses a package containing an agrochemicalcomprising a first sheet of non-planar water-soluble orwater-dispersible material and a second sheet of water-solubleor water-dispersible material superposed on the firstsheet and sealed to it.
• WO93/08095 discloses a two compartment thermoformed sachet inwhich a formed pocket is filled with a first composition thena first film is laid over the first composition and thesecond composition is added over the top of the first film.Finally a second film is overlaid over the pocket and the twofilms are sealed to a sealing portion of the formed pocket.
• The present application offers a simple process providingflexibility in the size and proportions of each compartment.In addition combinations of different formats, i.e. liquidfirst composition and solid second composition, are moreeasily produced and are more aesthetically pleasing.
• The present invention provides a process for producing awater-soluble article comprising a first compartment, forexample in the form of a pocket, said compartment beingsealed with a sealing film, wherein said sealing filmcomprises a second composition, for example held within asecond compartment, which process comprises:
• a. producing a first compartment;
• b. filling the first compartment with the firstcomposition; and
• c. providing a sealing film comprising a second compositionand sealing the first compartment with the sealing film;
wherein the first compartment is formed by thermoforming apoly (vinyl alcohol) film or wherein the first compartment ismade by injection moulding.
• The term "water soluble" is taken to include waterdispersible. The term "water-soluble" when used herein meansthat when used in a washing machine, such as a fabric or dishwashing machine, the water-soluble aspects of the article aresubstantially (greater than 70%, ideally greater than 85%)dissolved or dispersed into the water. This can be tested byplacing the article in 10 litres of agitated water at 45°Cfor 40 minutes and measuring any undissolved or non-disintegratedpieces of the parts of the article, which arewater-soluble, that are left.
• The containers produced by he process of the presentinvention can have a particularly attractive appearance sincethey contain two compositions held in a fixed position inrelation to each other. The compositions can be easilydifferentiated to accentuate their difference. For example,the compositions can have a different physical appearance, orcan be coloured differently. Thus, for example, the containers can have anappearance of a fried egg or eyeball.
• The container may contain two components which areincompatible with each other. It may also contain acomponent which is incompatible with the part of thecontainer enclosing the other component. For example, thesecond composition may be incompatible with the part of thecontainer enclosing the first composition.
• The invention allows the use of multi-compartment sachetswherein the first composition and the second composition areeach intended to be released into an aqueous environment, forexample, a pharmaceutical or neutraceutical composition, anagricultural or pesticidal composition or a hazardouscompound potentially toxic or damaging to health or to theenvironment.
• It is possible to ensure that the components are released atdifferent times. Thus, for instance, one composition can bereleased immediately the container is added to water, whereasthe other may be released later. This may be achieved byhaving a compartment which takes longer to dissolvesurrounding one of the compositions, which may be either thefirst or the second composition. This may be achieved, forexample, by having different compartment thicknesses ordifferent compartment materials or coatings. Alternatively,in one embodiment of the invention, the second compositionmay simply be held on the outside of the sealing film, inwhich case it can start to dissolve as soon as the article isadded to water. It may also be achieved by choosingcompartments which dissolve at different temperatures, for example the different temperatures encountered during thecycle of a laundry or dish washing machine.
• The first compartment may be formed of, for example, amoulded polymer, especially one produced by injectionmoulding or blow moulding. Injection moulding of water-solublepolymers is taught in WO01/36290. The walls of thecompartment may, for example, have a thickness of greaterthan 100 µm, for example greater than 150 µm or greater than200 µm, 300 µm, 500 µm, 750 µm or 1mm. Preferably the wallshave a thickness of from 200 to 400µm.
• It will be appreciated that the first compartment may berigid or flexible. The first compartment is preferably rigidwhen the first compartment is sealed with a sealing filmcomprising the second composition.
• The first compartment may also, for example, be formed of afilm. Preferably the first compartment is made from a film.
• Where a film is used it may be a single film, or a laminatedfilm as disclosed in GB-A-2,244,258 or a coated film. Whilea single film may have pinholes, the two or more layers in alaminate are unlikely to have pinholes which coincide.
• The film may be produced by any process, for example byextrusion and blowing or by casting. The film may beunoriented, monoaxially oriented or biaxially oriented. Ifthe layers in the film are oriented, they usually have the same orientation, although their planes of orientation may bedifferent if desired.
• The layers in a laminate may be the same or different. Thusthey may each comprise the same polymer or differentpolymers.
• Examples of water-soluble polymers which may be used in asingle layer film or in one or more layers of a laminate orwhich may be used for injection moulding are poly(vinylalcohol) (PVOH), cellulose derivatives such as hydroxypropylmethyl cellulose (HPMC), soluble polyurethane resins andgelatin. An example of a preferred PVOH is ethoxylated PVOH.The PVOH may be partially or fully alcoholised or hydrolysed.For example it may be from 40 to 100%, preferably from 70 to92%, more preferably about 88% or about 92%, alcoholised orhydrolysed. The degree of hydrolysis is known to influencethe temperature at which the PVOH starts to dissolve inwater. 88% hydrolysis corresponds to a film soluble in cold(ie room temperature) water, whereas 92% hydrolysiscorresponds to a film soluble in warm water.
• The thickness of the film used to produce the firstcompartment, which may be in the form of a pocket, ispreferably 40 to 300 µm, more preferably 80 to 200 µm,especially 100 to 160 µm, more especially 100 to 150 µm andideally 60 to 120µm.
• The film used for the first compartment or the sealing filmof the first or second container is preferably part of acontinuous film web.
• The compartment may be formed by, for example, vacuum formingor thermoforming. For example, in a thermoforming processthe film may be drawn down or blown down into a mould. Thus,for example, the film is heated to the thermoformingtemperature using a thermoforming heater plate assembly, andthen drawn down under vacuum or blown down under pressureinto the mould. Plug-assisted thermoforming and pre-stretchingthe film, for example by blowing the film awayfrom the mould before thermoforming, may, if desired, beused. One skilled in the art can choose an appropriatetemperature, pressure or vacuum and dwell time to achieve anappropriate pocket. The amount of vacuum or pressure and thethermoforming temperature used depend on the thickness of thefilm and on the polymer or mixture of polymers being used.Thermoforming of PVOH films is known and described in, forexample, WO 00/55045.
• A suitable forming temperature for PVOH or ethoxylated PVOHis, for example, from 90 to 130°C, especially 90 to 120°C. Asuitable forming pressure is, for example, 69 to 138kPa (10to 20 p.s.i.), especially 83 to 117 kPa (12 to 17 p.s.i.). Asuitable forming vacuum is 0 to 4 kPa (0 to 40 mbar),especially 0 to 2 kPa (0 to 20 mbar). A suitable dwell timeis, for example, 0.4 to 2.5 seconds, especially 2 to 2.5seconds.
• While desirably conditions are chosen within the aboveranges, it is possible to use one or more of these parametersoutside the above ranges, although it may be necessary tocompensate by changing the values of the other twoparameters.
• The first compartment is filled with the desired firstcomposition. The first compartment may be completely filledor only partially filled. The composition may be a solid.For example, it may be a particulate or granulated solid, ora tablet. It may also be a liquid, which may be thickened orgelled if desired. The liquid composition may be non-aqueousor aqueous, for example comprising less than or more than 5%total or free water respectively. The composition may havemore than one phase. For example it may comprise an aqueouscomposition and a liquid composition which is immiscible withthe aqueous composition. It may also comprise a liquidcomposition and a separate solid composition, for example inthe form of a ball, pill or speckles.
• The composition may be any composition that is intended to bereleased in an aqueous environment. Thus, for example, itmay be an agrochemical composition such as a plant protectionagent; for instance a pesticide, such as an insecticide, afungicide, an herbicide, an acaricide, or a nematocide; aplant growth regulator or a plant nutrient. Suchcompositions are generally packaged in amounts of from 0.1 gto 7 kg, preferably 1g to 5 kg, when in solid form. When inliquid or gelled form, such compositions are generallypackaged in amounts of from 1 ml to 10 litres, preferably 0.1to 6 litres, especially from 0.25 to 1.5 litres.
• The composition may be any composition intended forpharmaceutical or neutraceutical use. Thus, for example, itmay be a cold or flu remedy, or any other medicine, which maybe added to a drink, or it may be a vitamin, mineral or plantextract.
• The composition may be hazardous product, especially onewhich should not be handled directly or contact the skin.
• The first composition may also be a fabric care, surface careor dishwashing composition. Thus, for example, it may be adishwashing, water-softening, laundry or detergentcomposition, or a rinse aid. Such compositions may besuitable for use in a domestic washing machine. Thecomposition may also be a disinfectant, antibacterial orantiseptic composition, or a refill composition for atrigger-type spray. Such compositions are generally packagedin amounts of from 5 to 100 g, especially from 15 to 40 g.For example, a dishwashing composition may weigh from 15 to30 g, a water-softening composition may weigh from 15 to 40g.
• The composition, if in liquid form, may be anhydrous orcomprise water, for example at least 5 wt %, preferably atleast 10 wt% water based on the weight of the composition.Desirably the composition contains less than 80 wt% water. By"anhydrous" we mean that there is present less than 3 wt % ofwater, and ideally less than 0.5 wt %.
• The remaining ingredients of the first composition depend onthe use of the composition. Thus, for example, thecomposition may contain surface active agents such as ananionic, nonionic, cationic, amphoteric or zwitterionicsurface active agents or mixtures thereof,
• Examples of secondary alkyl sulfate surfactants are thosewhich have the sulfate moiety on a "backbone" of themolecule, for example those of formula:CH₃(CH₂)_n(CHOSO₃ ^-M⁺) (CH₂)_mCH₃ wherein m and n are independently 2 or more, the sum of m+ntypically being 6 to 20, for example 9 to 15, and M is awater-solubilising cation such as lithium, sodium orpotassium.
• Especially preferred secondary alkyl sulfates are the (2,3)alkyl sulfate surfactants of formulae:CH₃(CH₂)_x(CHOSO₃ ^-M⁺)CH₃ andCH₃(CH₂)_x(CHOSO₃ ^-M⁺)CH₂CH₃for the 2-sulfate and 3-sulfate, respectively. In theseformulae x is at least 4, for example 6 to 20, preferably 10to 16. M is cation, such as an alkali metal, for examplelithium, sodium or potassium.
• Examples of alkoxylated alkyl sulfates are ethoxylated alkylsulfates of the formula:RO(C₂H₄O)_nSO₃ ^-M⁺wherein R is a C₈-C₂₀ alkyl group, preferably C₁₀-C₁₈ such as aC₁₂-C₁₆, n is at least 1, for example from 1 to 20, preferably1 to 15, especially 1 to 6, and M is a salt-forming cationsuch as lithium, sodium, potassium, ammonium, alkylammoniumor alkanolammonium. These compounds can provide especiallydesirable fabric cleaning performance benefits when used incombination with alkyl sulfates.
• The alkyl sulfates and alkyl ether sulfates will generally beused in the form of mixtures comprising varying alkyl chainlengths and, if present, varying degrees of alkoxylation.
• Other anionic surfactants which may be employed are salts offatty acids, for example C₈-C₁₈ fatty acids, especially thesodium or potassium salts, and alkyl, for example C₈-C₁₈,benzene sulfonates.
• Examples of nonionic surfactants are fatty acid alkoxylates,such as fatty acid ethoxylates, especially those of formula:R(C₂H₄O)_nOHwherein R is a straight or branched C₈-C₁₆ alkyl group,preferably a C₉-C₁₅, for example C₁₀-C₁₄, alkyl group and n isat least 1, for example from 1 to 16, preferably 2 to 12,more preferably 3 to 10.
• The alkoxylated fatty alcohol nonionic surfactant willfrequently have a hydrophilic-lipophilic balance (HLB) whichranges from 3 to 17, more preferably from 6 to 15, mostpreferably from 10 to 15.
• Examples of fatty alcohol ethoxylates are those made fromalcohols of 12 to 15 carbon atoms and which contain about 7moles of ethylene oxide. Such materials are commerciallymarketed under the trademarks Neodol 25-7 and Neodol 23-6.5by Shell Chemical Company. Other useful Neodols includeNeodol 1-5, an ethoxylated fatty alcohol averaging 11 carbonatoms in its alkyl chain with about 5 moles of ethyleneoxide; Neodol 23-9, an ethoxylated primary C₁₂-C₁₃ alcoholhaving about 9 moles of ethylene oxide; and Neodol 91-10, anethoxylated C₉-C₁₁ primary alcohol having about 10 moles ofethylene oxide.
• Alcohol ethoxylates of this type have also been marketed byShell Chemical Company under the Dobanol trademark. Dobanol91-5 is an ethoxylated C₉-C₁₁ fatty alcohol with an average of5 moles ethylene oxide and Dobanol 25-7 is an ethoxylated C₁₂-C₁₅fatty alcohol with an average of 7 moles of ethylene oxideper mole of fatty alcohol.
• Other examples of suitable ethoxylated alcohol nonionicsurfactants include Tergitol 15-S-7 and Tergitol 15-S-9, bothof which are linear secondary alcohol ethoxylates availablefrom Union Carbide Corporation. Tergitol 15-S-7 is a mixedethoxylated product of a C₁₁-C₁₅ linear secondary alkanol with7 moles of ethylene oxide and Tergitol 15-S-9 is the same butwith 9 moles of ethylene oxide.
• Other suitable alcohol ethoxylated nonionic surfactants areNeodol 45-11, which is a similar ethylene oxide condensationproducts of a fatty alcohol having 14-15 carbon atoms and thenumber of ethylene oxide groups per mole being about 11.
  Such products are also available from Shell Chemical Company.
• Further nonionic surfactants are, for example, C₁₀-C₁₈ alkylpolyglycosides, such s C₁₂-C₁₆ alkyl polyglycosides,especially the polyglucosides. These are especially usefulwhen high foaming compositions are desired. Furthersurfactants are polyhydroxy fatty acid amides, such as C₁₀-C₁₈N-(3-methoxypropyl) glycamides and ethylene oxide-propyleneoxide block polymers of the Pluronic type.
• Examples of cationic surfactants are those of the quaternaryammonium type.
• The total content of surfactants in the composition isdesirably 60 to 95 wt%, especially 75 to 90 wt%. Desirablyan anionic surfactant is present in an amount of 50 to 75wt%, the nonionic surfactant is present in an amount of 5 to50 wt%, and/or the cationic surfactant is present in anamount of from 0 to 20 wt%. The amounts are based on thetotal solids content of the composition, i.e. excluding anysolvent which may be present.
• The first and second compositions, particularly when used aslaundry washing or dishwashing compositions, may alsoindependently comprise enzymes, such as protease, lipase,amylase, cellulase and peroxidase enzymes. Such enzymes arecommercially available and sold, for example, under theregistered trade marks Esperase, Alcalase and Savinase byNova Industries A/S and Maxatase by InternationalBiosynthetics, Inc. Desirably the enzymes are independentlypresent in the first or second compositions in an amount offrom 0.5 to 3 wt%, especially 1 to 2 wt%, when added ascommecial preparations they are not pure and this representsan equivalent amount of 0.005 to 0.5 wt% of pure enzyme.
• The first and second compositions may, if desired,independently comprise a thickening agent or gelling agent.Suitable thickeners are polyacrylate polymers such as thosesold under the trade mark CARBOPOL, or the trade mark ACUSOLby Rohm and Haas Company. Other suitable thickeners arexanthan gums. The thickener, if present, is generallypresent in an amount of from 0.2 to 4 wt%, especially 0.5 to2 wt%.
• First or second compositions used in dishwashingindependently usually comprise a detergency builder. The builders counteract the effects of calcium, or other ion,water hardness encountered. Examples of such materials arecitrate, succinate, malonate, carboxymethyl succinate,carboxylate, polycarboxylate and polyacetyl carboxylatesalts, for example with alkali metal or alkaline earth metalcations, or the corresponding free acids. Specific examplesare sodium, potassium and lithium salts of oxydisuccinicacid, mellitic acid, benzene polycarboxylic acids, C₁₀-C₂₂fatty acids and citric acid. Other examples are organicphosphonate type sequestering agents such as those sold byMonsanto under the trade mark Dequest and alkylhydroxyphosphonates. Citrate salts and C₁₂-C₁₈ fatty acid soaps arepreferred. Further builders are; phosphates such as sodium,potassium or ammonium salts of mono-, di- or tri-poly oroligo-phosphates; zeolites; silicates, amorphous orstructured, such as sodium, potassium or ammonium salts.Further builders are; phosphates such as sodium, potassium orammonium salts of mono-, di- or tri-poly or oligo-phosphates;zeolites; silicates, amorphous or structured, such as sodium,potassium or ammonium salts.
• Other suitable builders are polymers and copolymers known tohave builder properties. For example, such materials includeappropriate polyacrylic acid, polymaleic acid, andpolyacrylic/polymaleic and copolymers and their salts, suchas those sold by BASF under the trade mark Sokalan.
• The builder is desirably present in an amount of up to 90wt%, preferably 15 to 90 wt%, more preferable 15 to 75 wt%,relative to the total weight of the composition. Furtherdetails of suitable components are given in, for example, EP-A-694,059,EP-A-518,720 and WO 99/06522.
• The first and second compositions can also independentlyoptionally comprise one or more additional ingredients.These include conventional detergent composition componentssuch as further surfactants, bleaches, bleach enhancingagents, builders, suds boosters or suds suppressors, anti-tarnishand anti-corrosion agents, organic solvents, co-solvents,phase stabilisers, emulsifying agents,preservatives, soil suspending agents, soil release agents,germicides, pH adjusting agents or buffers, non-builderalkalinity sources, chelating agents, clays such as smectiteclays, enzyme stabilizers, anti-limescale agents, colourants,dyes, hydrotropes, dye transfer inhibiting agents,brighteners, and perfumes. If used, such optionalingredients will generally constitute no more than 15 wt%,for example from 1 to 6 wt%, the total weight of thecompositions.
• First or second compositions which comprise an enzyme mayoptionally contain materials which maintain the stability ofthe enzyme. Such enzyme stabilizers include, for example,polyols such as propylene glycol, boric acid and borax.Combinations of these enzyme stabilizers may also beemployed. If utilized, the enzyme stabilizers generallyconstitute from 0.1 to 5 wt%, ideally 0.1 to 1 wt% of thecompositions.
• The first and second compositions may independentlyoptionally comprise materials which serve as phasestabilizers and/or co-solvents. Example are C₁-C₃ alcoholssuch as methanol, ethanol and propanol. C₁-C₃ alkanolaminessuch as mono-, di- and triethanolamines can also be used, bythemselves or in combination with the alcohols. The phase stabilizers and/or co-solvents can, for example, constitute 0to 1 wt%, preferably 0.1 to 0.5 wt%, of the composition.
• The first and second compositions may independentlyoptionally comprise components which adjust or maintain thepH of the compositions at optimum levels. The pH may befrom, for example, 1 to 13, such as 8 to 11 depending on thenature of the composition. For example a dishwashingcomposition desirably has a pH of 8 to 11, a laundrycomposition desirable has a pH of 7 to 9, and a water-softeningcomposition desirably has a pH of 7 to 9. Examplesof pH adjusting agents are NaOH and citric acid.
• The above examples may be used for dish or fabric washing. Inparticular dish washing formulations are preferred which areadapted to be used in automatic dish washing machines. Due totheir specific requirements specialised formulation arerequired and these are illustrated below
• Amounts of the ingredients can vary within wide ranges,however preferred automatic dishwashing detergentcompositions herein (which typically have a 1% aqueoussolution pH of above 8, more preferably from 9.5 to 12, mostpreferably from 9.5 to 10.5) are those wherein there ispresent: from 5% to 90%, preferably from 5% to 75%, ofbuilder; from 0.1% to 40%, preferably from 0.5% to 30%, ofbleaching agent; from 0.1% to 15%, preferably from 0.2% to10%, of the surfactant system; from 0.0001% to 1%, preferablyfrom 0.001% to 0.05%, of a metal-containing bleach catalyst;and from 0.1% to 40%, preferably from 0.1% to 20% of a water-solublesilicate. Such fully-formulated embodiments typicallyfurther comprise from 0.1% to 15% of a polymeric dispersant,from 0.01% to 10% of a chelant, and from 0.00001% to 10% of a detersive enzyme, though further additional or adjunctingredients may be present. Detergent compositions herein ingranular form typically limit water content, for example toless than 7% free water, for better storage stability.
• Non-ionic surfactants useful in ADW (Automatic Dish Washing)compositions of the present invention desirably includesurfactant(s) at levels of from 2% to 60% of the composition.In general, bleach-stable surfactants are preferred. Non-ionicsurfactants generally are well known, being describedin more detail in Kirk Othmer's Encyclopedia of ChemicalTechnology, 3rd Ed., Vol. 22, pp. 360-379, "Surfactants andDetersive Systems", incorporated by reference herein.
• Preferably the ADW composition comprises at least one non-ionicsurfactant. One class of non-ionics are ethoxylatednon-ionic surfactants prepared by the reaction of amonohydroxy alkanol or alkylphenol with 6 to 20 carbon atomswith preferably at least 12 moles particularly preferred atleast 16 moles, and still more preferred at least 20 moles ofethylene oxide per mole of alcohol or alkylphenol.
• Particularly preferred non-ionic surfactants are the non-ionicfrom a linear chain fatty alcohol with 16-20 carbonatoms and at least 12 moles particularly preferred at least16 and still more preferred at least 20 moles of ethyleneoxide per mole of alcohol.
• According to one preferred embodiment the non-ionicsurfactant additionally comprise propylene oxide units in themolecule. Preferably this PO units constitute up to 25% byweight, preferably up to 20% by weight and still morepreferably up to 15% by weight of the overall molecular weight of the non-ionic surfactant. Particularly preferredsurfactants are ethoxylated mono-hydroxy alkanols oralkylphenols, which additionally comprises polyoxyethylene-polyoxypropyleneblock copolymer units. The alcohol oralkylphenol portion of such surfactants constitutes more than30%, preferably more than 50%, more preferably more than 70%by weight of the overall molecular weight of the non-ionicsurfactant.
• Another class of non-ionic surfactants includes reverse blockcopolymers of polyoxyethylene and polyoxypropylene and blockcopolymers of polyoxyethylene and polyoxypropylene initiatedwith trimethylolpropane.
• Another preferred non-ionic surfactant can be described bythe formula:R¹O[CH₂CH(CH₃)O]_x[CH₂CH₂O]_y[CH₂CH(OH)R²]whereinR¹ represents a linear or branched chain aliphatichydrocarbon group with 4-18 carbon atoms or mixturesthereof,R² represents a linear or branched chain aliphatichydrocarbon rest with 2-26 carbon atoms or mixtures thereof,x is a value between 0.5 and 1.5 andy is a value of at least15.
• Another group of preferred nonionic surfactants are the end-cappedpolyoxyalkylated non-ionics of formula:R¹O[CH₂CH(R³)O]_x[CH₂]_kCH(OH) [CH₂]_jOR²wherein R¹ and R² represent linear or branched chain,saturated or unsaturated, aliphatic or aromatic hydrocarbon groups with 1-30 carbon atoms, R³ represents a hydrogenatom or a methyl, ethyl, n-propyl, iso-propyl, n-butyl, 2-butylor 2-methyl-2-butyl group , x is a value between 1 and30 and, k and j are values between 1 and 12, preferablybetween 1 and 5. When the value of x is ≥2 each R³ in theformula above can be different. R¹ and R² are preferablylinear or branched chain, saturated or unsaturated, aliphaticor aromatic hydrocarbon groups with 6-22 carbon atoms,where group with 8 to 18 carbon atoms are particularlypreferred. For the group R³ H, methyl or ethyl areparticularly preferred. Particularly preferred values for xare comprised between 1 and 20, preferably between 6 and 15.
• As described above, in case x≥2, each R³ in the formula canbe different. For instance, when x=3, the group R³ could bechosen to build ethylene oxide (R³=H) or propylene oxide(R³=methyl) units which can be used in every single order forinstance (PO) (EO) (EO), (EO) (PO) (EO), (EO) (EO) (PO),(EO) (EO) (EO), (PO) (EO) (PO), (PO) (PO) (EO) and (PO) (PO) (PO).The value 3 for x is only an example and bigger values can bechosen whereby a higher number of variations of (EO) or (PO)units would arise.
• Particularly preferred end-capped polyoxyalkylated alcoholsof the above formula are those where k=1 and j=1 originatingmolecules of simplified formula:R¹O[CH₂CH(R³)O]_xCH₂CH(OH)CH₂OR²
• The use of mixtures of different non-ionic surfactants isparticularly preferred in ADW formulations for examplemixtures of alkoxylated alcohols and hydroxy group containingalkoxylated alcohols.
• The first composition and the second composition may be thesame or different. If they are different, they may,nevertheless, have one or more individual components incommon.
• After the first compartment has been filled, a sealing filmis placed on top of the first compartment and sealed thereto.
• The sealing film comprises a secondcomposition at the time it is placed on top of the firstcompartment. This may be held or otherwise adhered on thesealing film. For example it can be in the form of a solidcomposition such as a ball or pill held on the sealing memberby an adhesive or by mechanical means. This is especiallyappropriate when the sealing film has a degree of rigidity.It is also possible for a previously prepared containercontaining the second composition to be adhered to thesealing film. For example, a sealing film may have a filledcompartment containing a composition attached therebetween,within or to the sealing film. Preferably the firstcompartment is sealed by the sealing film of the secondcompartment.
• The second composition or compartment may be held on eitherside of the sealing film such that it is inside or outsidethe first compartment.
• Generally, however, the second composition is held within asecond compartment in the sealing film. This is especiallyappropriate when the sealing film is flexible.
• The sealing film is placed on top of the first compartmentand sealed thereto. For example the sealing film may be placed over a filled compartment and across the sealingportion, if present, and the films sealed together at thesealing portion. In general there is only one secondcompartment or composition within or on the sealing film, butit is possible to have more than one second compartment orcomposition if desired, for example 2 or 3 secondcompartments or compositions.
• The second compartment may be formed by any technique. Forexample it can be formed by vertical form fill sealing thesecond composition within a film, such as by the processdescribed in WO 89/12587.
• However, it is preferred to use vacuum forming orthermoforming techniques, such as that previously describedin relation to the first compartment of the container of thepresent invention. Thus, for example, a pocket surrounded bya sealing portion is formed in a film, the pocket is filledwith the second composition, a film is placed on top of thefilled pocket and across the sealing portion and the 3 filmsare sealed together at the sealing portion.
• Further details of this thermoforming process are generallythe same as those given above in relation to the firstcompartment of the container of the present invention. Allof the above details are incorporated by reference to thesecond compartment, with the following differences:
• The second compartment is generally smaller than the firstcompartment since the film containing the second compositionis used to form a lid on the first compartment. In generalthe first compartment and the second compartment (orcomposition if not held within a compartment) have a volume ratio of from 2:1 to 20:1, preferable 4:1 to 10:1. Generallythe second compartment does not extend across the sealingportion.
• The thickness of the film or films comprising the secondcompartment may also be less than the thickness of the filmmaking up the first compartment of the container of thepresent invention, because the film or films are notsubjected to as much localised stretching in thethermoforming step. It is also desirable to have a thicknesswhich is less than that of the film used to form the firstcompartment to ensure a sufficient heat transfer through thefilm to soften the base web if heat sealing is used.
• The thickness of the covering film is generally from 20 to160 µm, preferably from 40 to 100 µm, such as 40 to 80 µm or50 to 60 µm.
• This sealing film may be a single-layered film but isdesirably laminated to reduce the possibility of pinholesallowing leakage through the film. The film may be the sameor different as the film forming the first compartment. Iftwo or more films are used to form the film comprising thesecond compartment, the films may be the same or different.Examples of suitable films are those given for the filmforming the first compartment.
• The first compartment and the sealing film may be sealedtogether by any suitable means, for example by means of anadhesive or by heat sealing. Other methods of sealing includeinfra-red, radio frequency, ultrasonic, laser, solvent,vibration and spin welding. An adhesive such as an aqueous solution of PVOH may also be used. The seal desirably iswater-soluble.
• If heat sealing is used, a suitable sealing temperature is,for example, 120 to 195°C, for example 140 to 150°C. Asuitable sealing pressure is, for example, from 250 to 600kPa. Examples of sealing pressures are 276 to 552 kPa (40 to80 p.s.i.), especially 345 to 483 kPa (50 to 70 p.s.i.) or400 to 800 kPa (4 to 8 bar), especially 500 to 700 kPa (5 to7 bar) depending on the heat sealing machine used. Suitablesealing dwell times are 0.4 to 2.5 seconds.
• One skilled in the art can use an appropriate temperature,pressure and dwell time to achieve a seal of the desiredintegrity. While desirably conditions are chosen within theabove ranges, it is possible to use one or more of theseparameters outside the above ranges, although it would mightbe necessary to compensate by changing the values of theother two parameters.
• If more than one container is formed at the same time fromthe same sheet, the containers may then be separated fromeach other, for example by cutting around the sealingportions, or flanges. Alternatively, they may be leftconjoined and, for example, perforations provided between theindividual containers so that they can be easily separated ata later stage, for example by a consumer. If the containersare separated, the flanges are at least in part left inplace. However, desirably the flanges are partially removedin order to provide an even more attractive appearance.Generally the flanges remaining should be as small aspossible for aesthetic purposes while bearing in mind thatsome flange is required to ensure the two films remain adhered to each other. A flange having a width of 1 mm to 8mm is desirable, preferably 2 mm to 7 mm, most preferablyabout
  5 mm.
• The containers may themselves be packaged in outer containersif desired, for example non-water soluble containers whichare removed before the water-soluble containers are used.
• The containers produced by the process of the presentinvention, especially when used for a fabric care, surfacecare or dishwashing composition, may have a maximum dimensionof 5 cm, excluding any flanges. For example, a container mayhave a length of 1 to 5 cm, especially 3.5 to 4.5 cm, a widthof 1.5 to 3.5 cm, especially 2 to 3 cm, and a height of 1 to2 cm, especially 1.25 to 1.75 cm.
• The first composition and the second composition may beappropriately chosen depending on the desired use of thearticle.
• If the article is for use in laundry washing, the firstcomposition may comprise, for example, a detergent, and thesecond composition may comprise a bleach, stain remover,water-softener, enzyme or fabric conditioner. The articlemay be adapted to release the compositions at different timesduring the laundry wash. For example, a bleach or fabricconditioner is generally released at the end of a wash, and awater-softener is generally released at the start of a wash.An enzyme may be released at the start or the end of a wash.
• If the article is for use as a fabric conditioner, the firstcomposition may comprise a fabric conditioner and the secondcomposition may comprise an enzyme which is released beforeor after the fabric conditioner in a rinse cycle.
• If the article is for use in dish washing the firstcomposition may comprise a detergent and the secondcomposition may comprise a water-softener, salt, enzyme,rinse aid, bleach or bleach activator. The article may beadapted to release the compositions at different times duringthe laundry wash. For example, a rinse aid, bleach or bleachactivator is generally released at the end of a wash, and awater-softener, enzyme is generally released at the start ofa wash.
• If the article is for use as an agrochemical product, thefirst compartment may comprise a plant feed and the secondcompartment may comprise a pesticidal composition.
• If the article is for use as a pharmaceutical/nutraceuticalcomposition, the first compartment may comprise anutraceutical composition and the second compartment apharmaceutical composition.
• The containers of the present invention will now be furtherdescribed with reference to figures 1 to 4. These illustrateexamples of containers which can be produced.
• Each figure shows an article containing a first compartment 1and a second composition 2. In figures 1 to 3, the secondcomposition is held in a second compartment in a sealing member in the form of a film. In figure 4 the secondcomposition is simply held in a recess in the sealing member.

Claims (10)

1. A process for producing a water-soluble articlecomprising a first compartment containing a firstcomposition, said compartment being sealed with a sealingfilm, wherein said sealing film comprises a secondcomposition, which process comprises:

   a. producing a first compartment;

   b. filling the first compartment with the firstcomposition; and

   c. providing a sealing film comprising the secondcomposition and sealing the first compartment with thesealing film;

      wherein the first compartment is formed by thermoforminga poly(vinyl alcohol) film or wherein the first compartmentis made by injection moulding.
2. A process according to claim 1 wherein the firstcompartment and the sealing film comprise a poly(vinylalcohol).
3. A process according to claims 1 or 2 wherein the firstcomposition is a particulate solid, a gel or a liquid.
4. A process according to claim 1 wherein the secondcomposition is held in a second compartment which has beenformed by a vertical form fill sealing method.
5. A process according to any one of claims 1 to 4 whereinat least one compartment has been formed by thermoforming.
6. A process according to any one of the preceding claimswherein the second composition is a particulate solid, a gel,a liquid or a compressed solid.
7. A process according to any one of the preceding claimswherein the first composition and the second composition areeach a fabric care, surface care or dishwashing composition.
8. A process according to claim 7 wherein each compositionis a dishwashing, water-softening, laundry or detergentcomposition or a rinse aid.
9. A process according to claim 7 wherein each compositionis a disinfectant, antibacterial or antiseptic composition ora refill composition for a trigger-type spray.
10. A process accordingly to any one of claims 1 to 6wherein the first composition and the second composition areeach compositions which are intended to be released into anaqueous environment for example, a pharmaceutical orneutraceutical composition, an agriculture or pesticidalcomposition or a hazardous compound potentially toxic ordamaging to health or to the environment.

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