Resin composition for release paper or release film, release paper and release film

Abstract

[Problem] To provide a resin composition for a release liner or release film that yields a cured film with good peelability and repeatability in both cases of curing at low temperature and curing in a short time. [Solution] (A) Hydroxyl group-containing acrylic resin having a hydroxyl value of 140–180 mgKOH / g, (B) a resin selected from full ether-type methylated melamine resins, methylol-type methylated melamine resins, and polymers thereof, and (C) An organopolysiloxane having two or more functional groups in one molecule capable of chemically bonding to one or more resins selected from component (A) and component (B). A resin composition for release paper or release film comprising

Description

Technology Field

[0001] The present invention relates to a resin composition for a release liner or a release film, and a release liner or a release film having a cured film formed by curing the composition on a substrate. Background Technology

[0002] Conventionally, a release agent is applied to the surface of a sheet-shaped substrate, such as paper or plastic, and a cured film is formed to impart release properties to adhesive or tacky materials.

[0003] Release liners and release films have a wide range of applications. They are used for adhesive materials such as labels, stickers, and tapes, or in molding processes for non-adhesive materials such as ceramic layers and urethane resins; therefore, different performance characteristics are required depending on the application.

[0004] An example of a material used in the molding process of non-stick materials is a process paper for manufacturing synthetic leather. In the manufacturing process of synthetic leather, a release agent is cured onto a substrate to form a process paper, and a urethane resin, vinyl chloride resin, polyamide resin, polyamino acid resin, etc., is applied onto this process paper and dried. Synthetic leather is manufactured by forming an adhesive layer on the dried resin, attaching a substrate, and peeling the resin from the process paper.

[0005] Synthetic leather comes in matte (gloss-free) and enamel (high gloss) types. However, in the manufacture of enamel-type synthetic leather, a high gloss is required for the cured film because the surface condition of the release agent film is reflected in the synthetic leather. Additionally, to increase the productivity of synthetic leather, the process paper is generally used multiple times. Therefore, it is desirable that the change in peelability (release properties) be minimal upon repeated use.

[0006] Polypropylene-based, aminoalkyd resin / aminoacrylic resin-based, and silicone-based resin compositions are known to be representative resin compositions for making the surface of process paper for synthetic leather release paper. Polypropylene-based compositions have excellent release endurance when used repeatedly, but they have limitations when used at relatively high temperatures, in which case the release surface is prone to scratching, and they also have difficulties such as being unsuitable for enamel-type synthetic leather. Aminoalkyd resin / aminoacrylic resin-based compositions have excellent gloss but lack release properties. Silicone-based compositions have excellent release properties but poor gloss, making them unsuitable for enamel-type synthetic leather.

[0007] In order to solve the above problems, Patent Document 1 (Japanese Patent Publication No. 56-14550) discloses a resin composition for process release paper comprising a silicone-modified acrylic resin formed by modifying an organopolysiloxane in which 15 to 50 mol% of the organic groups bonded to silicon atoms in one molecule are phenyl groups and at least one of the remaining organic groups is a hydroxyl group-substituted organic group, and a polyisocyanate compound. It is also stated that "by using hydroxyl group-substituted organic groups, a process release paper having excellent heat resistance, good gloss, and good release properties can be obtained."

[0008] In addition, Patent Document 2 (Japanese Patent Publication No. 56-11980) discloses a resin composition for process release paper comprising a silicone-modified alkyd resin formed by modifying an organopolysiloxane in which 15 to 50 mol% of the organic groups bonded to silicon atoms in one molecule are phenyl groups and at least one of the remaining organic groups is a hydroxyl group-substituted organic group, and a polyisocyanate compound. It is also stated that "even with process release paper using alkyd resin, it is possible to obtain process release paper that has excellent heat resistance, good gloss, and good release properties."

[0009] Patent Document 3 (Japanese Patent Publication No. 56-14566) discloses a resin composition for process release paper comprising a silicone-modified acrylic resin formed by modifying an organopolysiloxane in which 15 to 50 mol% of the organic groups bonded to silicon atoms in one molecule are phenyl groups and at least one of the remaining organic groups is a hydroxyl group-substituted organic group, an alkanol-modified amino resin, and an acidic catalyst. It is also stated that "by means of an acidic catalyst, a process release paper comprising both an acrylic resin and an amino resin can be obtained that has excellent heat resistance, good gloss, and good release properties."

[0010] Patent Document 4 (Japanese Patent Publication No. Hei 3-263475) discloses a resin composition for process release paper comprising a silicone-modified alkyd resin formed by modifying an organopolysiloxane in which a methyl group, a phenyl group, and an organic group are bonded to a silicon atom, at least one of the organic groups is a hydroxyl group-substituted organic group, and 15 to 50 mol% of the total substituents bonded to the silicon atom are phenyl groups, an alkanol-modified amino resin, and an acidic catalyst. It is also stated that "by using an acidic catalyst, a process release paper comprising both an alkyd resin and an amino resin can be obtained that has excellent heat resistance, good gloss, and good release properties."

[0011] Patent Document 5 (Japanese Patent Publication No. Hei 2-28242) discloses a resin composition for process release paper comprising an alkyd resin or an acrylic resin, an organopolysiloxane in which 15 to 50 mol% of the silicon atom bonded organic groups in one molecule are phenyl groups and at least one of the remaining organic groups is a hydroxyl group substituted organic group, an alkanol-modified amino resin, and an acidic catalyst. It is also stated, "The process release paper obtained by this resin composition for process release paper has excellent releaseability and heat resistance, and good gloss compared to conventional process release papers."

[0012] Patent Document 6 (Japanese Patent No. 5282083) discloses a release agent composition comprising a hydroxyl group-containing acrylic resin having a hydroxyl group value of 10 to 150 mgKOH / g, a glass transition temperature of 20 to 100°C, and a weight-average molecular weight of 20,000 to 100,000, an amino resin, and a silicone resin having a functional group capable of chemically bonding to at least one of the hydroxyl group-containing acrylic resin and the amino resin. It is also stated that "it has excellent release properties, gloss, surface condition, and repeatability at high temperatures."

[0013] As mentioned above, aminoalkyd resin and aminoacrylic resin-based release agents have improved gloss, heat resistance, and release properties, and have achieved certain effects. However, aminoalkyd resin and aminoacrylic resin-based release agents have the drawback of slow curing, so it was necessary to improve the curing properties.

[0014] In order to solve the above problems, Patent Document 7 (Japanese Patent Publication No. 2000-095929) discloses a release agent composition for process release paper comprising an alkyd resin, an amino resin, and a silicone resin containing a functional group reactive to the alkyd resin and the amino resin, wherein the amino resin contains at least one methylol group per triazine nucleus, and the methylated melamine resin is contained as a main component, and it is described as having "excellent peelability, gloss, surface condition, and reusability, and is capable of curing and drying at low temperatures."

[0015] Recently, there has been a strong demand for release agent compositions capable of curing at low temperatures or curing in a short time to increase the production efficiency of process papers. If curing is possible at low temperatures, the amount of heat required during production can be reduced, thereby increasing production efficiency. On the other hand, if curing is possible in a short time, the production speed can be accelerated, which also increases production efficiency. Therefore, if a release agent composition capable of curing at low temperatures and in a short time can be identified, it becomes possible to provide stable quality without being affected by changes in curing temperature and curing time resulting from production efficiency improvements.

[0016] It has been found through investigation that aminoalkyd resin and aminoacrylic resin-based release agents have a low amount of silicone resin that imparts release properties, and therefore the release characteristics change depending on whether or not the silicone can be immobilized on the surface layer. This leads to instability in quality, as the release characteristics change when cured at low temperatures and when cured in a short time. However, in conventional release agent compositions, no composition capable of achieving both low-temperature curing and short-time curing properties is found. Prior art literature

[0017] Japanese Patent Publication No. 56-14550, Japanese Patent Publication No. 56-11980, Japanese Patent Publication No. 56-14566, Japanese Patent Publication No. 3-263475, Japanese Patent Publication No. 2-28242, Japanese Patent No. 5282083, Japanese Patent Publication No. 2000-095929 The problem to be solved

[0018] The present invention has been made in consideration of the above circumstances and aims to provide a resin composition for a release liner or release film capable of forming a release film with good releaseability and repeatability in both cases of curing at a low temperature and curing in a short time, and a release liner or release film having a cured film formed by curing the composition on a substrate. means of solving the problem

[0019] As a result of conducting a thorough examination to achieve the above objective, the inventors discovered that a resin composition comprising (A) a hydroxyl group-containing acrylic resin having a hydroxyl group value of 140 to 180 mgKOH / g, (B) a resin selected from a full ether-type methylated melamine resin, a methylol-type methylated melamine resin, and a polymer thereof, and (C) an organopolysiloxane having two or more functional groups in one molecule capable of chemically bonding to one or more resins selected from the components of (A) and (B), is suitable as a resin composition for release paper or release film, and thus the present invention was made.

[0020] Accordingly, the present invention provides the following resin composition for a release liner or a release film, and a release liner or a release film.

[0021] 1. (A) Hydroxyl group-containing acrylic resin having a hydroxyl group value of 140–180 mgKOH / g,

[0022] (B) a resin selected from full ether-type methylated melamine resins, methylol-type methylated melamine resins, and polymers thereof, and

[0023] (C) An organopolysiloxane having two or more functional groups in one molecule capable of chemically bonding to one or more resins selected from component (A) and component (B).

[0024] A resin composition for release paper or release film comprising

[0025] 2. (A) A resin composition for a release liner or release film as described in 1, wherein the weight-average molecular weight of the component is 5,000 to 400,000.

[0026] 3. A resin composition for a release liner or release film described in 1 or 2, wherein the amount of (B) component is 10 to 120 parts by mass per 100 parts by mass of (A) component.

[0027] 4. (B) A resin composition for a release liner or release film as described in any one of 1 to 3, wherein the component is a resin selected from a full ether-type methylated melamine resin and a polymer thereof.

[0028] 5. A resin composition for a release liner or release film described in any one of 1 to 4, wherein the amount of (C) component is 0.5 to 20 parts by mass per 100 parts by mass of (A) component.

[0029] 6. (C) A resin composition for a release liner or release film as described in any one of 1 to 5, comprising an organopolysiloxane in which 10 to 60 mol% of the organic groups bonded to silicon atoms in one molecule are phenyl groups.

[0030] 7. (D) A resin composition for a release liner or release film as described in any one of 1 to 6, further comprising an acidic catalyst.

[0031] 8. A release liner or release film having a cured film formed by heating a substrate after coating it with a resin composition for a release liner or release film described in any one of 1 to 7. Effects of the invention

[0032] The resin composition for release paper or release film of the present invention can form a release film with good release properties and repeatability, whether cured at a low temperature or cured in a short time, and has a gloss equivalent to or greater than that of conventional release agent compositions. Specific details for implementing the invention

[0033] (Form for carrying out the invention)

[0034] The present invention will be described in more detail below. Hereinafter, the "resin composition for release paper or release film" may be abbreviated simply as "composition."

[0035] [(A) Ingredient]

[0036] The component (A) of the present invention is a hydroxyl group-containing acrylic resin having a hydroxyl group value of 140 to 180 mgKOH / g, and can be used alone or in a suitable combination of two or more types.

[0037] The hydroxyl group value of the hydroxyl group-containing acrylic resin is 140 to 180 mgKOH / g, and is particularly preferably 141 to 178 mgKOH / g. If the hydroxyl group value is less than 140 mgKOH / g, the peelability and repeatability when cured in a short time are poor. On the other hand, if the hydroxyl group value exceeds 180 mgKOH / g, the surface condition of the cured film deteriorates and the gloss is reduced. In addition, in the present invention, the hydroxyl group value of the hydroxyl group-containing acrylic resin is adopted as a value measured in accordance with the neutralization titration method (JIS K0070).

[0038] In the present invention, by using a hydroxyl group-containing acrylic resin with a hydroxyl group value of 140 to 180 mgKOH / g as component (A), it was found that peelability and repeatability are good in both cases of curing at low temperature and curing in a short time. Although not bound by theory, it is believed that peelability is improved as the organopolysiloxane of component (C) is immobilized on the surface of the coating film. Therefore, it is presumed that as the curing time becomes shorter, the time for the organopolysiloxane to migrate to the surface layer decreases, and it becomes immobilized within the film before migrating to the surface layer, resulting in poor peelability. As the amount of hydroxyl groups of component (A) increases, the compatibility between component (A) and the organopolysiloxane of component (C) deteriorates, making migration to the surface easier. Therefore, it is believed that even under short-time curing conditions, a film in which the organopolysiloxane is immobilized on the film surface is obtained, exhibiting excellent peelability and repeatability.

[0039] (A) As for the hydroxyl group-containing acrylic resin of component A, it is not particularly limited to any hydroxyl group-containing acrylic resin having the specific hydroxyl group value described above, but it is preferable to use a copolymer of a radical polymerizable monomer (Aa) having one or more hydroxyl groups in one molecule and one or more radical polymerizable groups in one molecule, and a radical polymerizable monomer (Ab) having one or more radical polymerizable groups in one molecule and not having hydroxyl groups in one molecule.

[0040] Here, (Aa) is not particularly limited as long as it is a radical polymerizable monomer having at least one hydroxyl group and at least one radical polymerizable group in one molecule, and may be used alone or in a mixture of two or more types. Examples of radical polymerizable groups include acrylic groups, methacrylic groups, styryl groups, cinnamate ester groups, vinyl groups, allyl groups, etc.

[0041] (Aa) As components, specifically, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 1,4-cyclohexanedimethanol (meth)acrylate, 2-hydroxyethyl (meth)acrylate, and the Flaxel F series (manufactured by Daicel Co., Ltd.) modified with caprolactone are exemplified.

[0042] In addition, as for the (Ab) component, any radical polymerizable monomer having one or more radical polymerizable groups in one molecule that does not have a hydroxyl group in one molecule is not particularly limited and can be used alone or in a suitable combination of two or more types. Examples of radical polymerizable groups include acrylic groups, methacrylic groups, styryl groups, cinnamate ester groups, vinyl groups, allyl groups, etc.

[0043] (Ab) As a component, specifically, styrene compounds such as styrene, o-methylstyrene, p-methylstyrene, α-methylstyrene; ester compounds of (meth)acrylic acid such as methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, isobornyl (meth)acrylate, trifluoropropyl (meth)acrylate, perfluorobutylethyl (meth)acrylate, perfluorooctylethyl (meth)acrylate; Epoxy group-containing radical polymerizable monomers such as glycidyl (meth)acrylate, β-methylglycidyl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate; Radical polymerizable silane compounds such as γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropyldimethylmethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-methacryloxypropyltribubutoxysilane, γ-methacryloxypropyltriisopropeneoxysilane, γ-acryloxypropyltrimethoxysilane, acryloxymethyltrimethoxysilane, γ-acryloxypropyltriethoxysilane, γ-acryloxypropylmethyldiethoxysilane, styryltrimethoxysilane, styryltriethoxysilane, α-methylstyryltrimethoxysilane; radical polymerizable monomers containing polyoxyalkylene groups; glycerol (meth)acrylate, etc. are examples.

[0044] The polymerization ratio between component (Aa) and component (Ab) is adjusted according to the hydroxyl group value of the hydroxyl group-containing acrylic resin. The hydroxyl group value of the hydroxyl group-containing acrylic resin obtained by polymerization needs to be 140 to 180 mgKOH / g. Specifically, the polymerization ratio between component (Aa) and component (Ab) is preferably 1:0.1 to 1:10 in molar ratio ((Aa):(Ab)) of component (Aa) and component (Ab), and more preferably 1:0.3 to 1:5. If component (Aa) is too low or too high, synthesis may become difficult.

[0045] Copolymerization of component (Aa) and component (Ab) is carried out in the presence of a conventional radical polymerization initiator, such as peroxides including benzoyl peroxide, dicumyl peroxide, lauroyl peroxide, 2-ethylperoxyhexanoate tert-butyl, and azo compounds including 2,2'-azobis(2-methylbutyronitrile), and any of the solution polymerization, emulsion polymerization, suspension polymerization, or bulk polymerization methods may be applied.

[0046] In addition, the amount of polymerization initiator used is preferably 0.01 to 10 parts by mass and more preferably 0.02 to 5 parts by mass per 100 parts by mass of the total of components (Aa) and (Ab).

[0047] In the present invention, among these polymerization methods, solution polymerization is preferred because it is easy to adjust the weight-average molecular weight of (A) the hydroxyl group-containing acrylic resin to an optimal range.

[0048] Solvents used in this case include aromatic hydrocarbons such as benzene, toluene, and xylene; ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; esters such as ethyl acetate, n-butyl acetate, and isobutyl acetate; and monohydric alcohols such as ethanol, isopropanol, n-butanol, and isobutanol, and can be used alone or in a suitable combination of two or more.

[0049] The amount of solvent used is preferably 10 to 900 parts by mass for every 100 parts by mass of the total of components (Aa) and (Ab), and more preferably 20 to 800 parts by mass.

[0050] When copolymerizing component (Aa) and component (Ab) by solution polymerization, it is preferable to use polymerization conditions of 50 to 180°C, particularly 60 to 120°C for 1 to 15 hours, particularly 2 to 10 hours.

[0051] (A) The weight-average molecular weight of the component is preferably 5,000 to 400,000, more preferably 10,000 to 300,000, and even more preferably 20,000 to 200,000. If the weight-average molecular weight is within the above range, the coating properties and handling properties are good. In addition, the weight-average molecular weight is a polystyrene equivalent value obtained by gel permeation chromatography (hereinafter abbreviated as "GPC") using tetrahydrofuran as the developing solvent.

[0052] [(B) Ingredient]

[0053] (B) The component is a resin selected from full ether-type methylated melamine resin, methylol-type methylated melamine resin, and polymers thereof, and can be used alone or in a suitable combination of two or more types. In the present invention, the component (B) comprises a structure in which a functional group is bonded through three nitrogen atoms around a triazine ring. The component (B) acts as a crosslinking agent that reacts with the component (A) and / or the component (C).

[0054] Melamine resin is a synthetic resin obtained by condensing melamine and formaldehyde, and is a condensation product composed of monomers or polymers of two or more. It has an imino group, a methylol group, or an alkoxymethyl group as a functional group in one molecule, and is classified into full ether type, methylol type, imino type, and methylol / imino type depending on the functional group.

[0055] In addition, melamine resins are classified according to the type of alkoxymethyl group, melamine resins in which all alkoxymethyl groups are methoxymethyl groups are methylated melamine resins, melamine resins in which all alkoxymethyl groups are n-butoxymethyl groups are n-butylated melamine resins, and melamine resins in which methoxymethyl groups and n-butoxymethyl groups are mixed in the alkoxymethyl groups are methylated / n-butylated melamine resins.

[0056] In the present invention, component (B) is used such that a cured film with excellent peelability, repeatability, and curability is obtained, and a full ether-type methylated melamine resin, a methylol-type methylated melamine resin, and a polymer thereof are used, and a full ether-type methylated melamine resin and a polymer thereof are preferred.

[0057] In the present invention, component (B) may be commercially available or synthesized according to conventionally known methods. Examples of commercially available products include Cymel 300, Cymel 303LF, Cymel 350, Cymel 370N (all manufactured by AllNex Japan Co., Ltd.), Nikalac MW-30M, Nikalac MW-30 (all manufactured by Nihon Carbide Co., Ltd.), etc.

[0058] (B) The amount of component (B) is preferably 10 to 120 parts by mass with respect to 100 parts by mass of component (A), more preferably 15 to 110 parts by mass, and even more preferably 20 to 100 parts by mass. Within the above range, a cured film with good peelability and curability and excellent repeatability is obtained.

[0059] [(C) Ingredient]

[0060] The component (C) of the present invention is an organopolysiloxane having two or more, preferably two to four, functional groups in one molecule that can chemically bond with one or more resins selected from components (A) and (B), and can be used alone or in a suitable combination of two or more types. By having two or more functional groups in one molecule that can chemically bond with one or more resins selected from components (A) and (B), the component (C) which is the release component can be chemically bonded to the components (A) and (B) that form the release layer, thereby suppressing the migration of the component (C) into the adhesive layer, so that excessive peeling during tape storage or a decrease in adhesive strength during use can be prevented.

[0061] Examples of such functional groups include hydroxyl groups, amino groups, carboxyl groups, epoxy groups, isocyanate groups, etc., and hydroxyl groups and epoxy groups are preferred, and hydroxyl groups are more preferred.

[0062] (C) The organopolysiloxane of the component may have a straight chain or branched chain structure within the range in which the functional effects of the present invention can be exerted, but an organopolysiloxane represented by the following average composition formula (1) is preferred.

[0063]

[0064] (during food, R 1 is an independent, unsubstituted or substituted monovalent hydrocarbon group having 1 to 20 carbon atoms, or a monovalent organic group having 1 to 20 carbon atoms having a hydroxyl group, an amino group, a carboxyl group, an epoxy group, or an isocyanate group, and R 1 At least two of the groups are monovalent organic groups having 1 to 20 carbon atoms, having a hydroxyl group, an amino group, a carboxyl group, an epoxy group, or an isocyanate group. a is an integer greater than or equal to 2, b is an integer greater than or equal to 1, c is an integer greater than or equal to 0, and d is an integer greater than or equal to 0, and 4 ≤ a + b + c + d ≤ 500.

[0065] In the above equation (1), R 1 Examples include unsubstituted or substituted monovalent hydrocarbon groups having 1 to 20 carbon atoms, specifically, alkyl groups having 1 to 20 carbon atoms, preferably 1 to 6, such as methyl groups, ethyl groups, propyl groups, butyl groups, etc.; cycloalkyl groups having 3 to 20 carbon atoms, preferably 5 to 8, such as cyclohexyl groups; aryl groups having 6 to 20 carbon atoms, preferably 6 to 10, such as phenyl groups, tolyl groups, etc.; aralkyl groups having 7 to 20 carbon atoms, preferably 7 to 10, such as benzyl groups, etc.; or halogen-substituted alkyl groups having 1 to 20 carbon atoms, preferably 1 to 10, selected from hydroxypropyl groups, 1-chloropropyl groups, 3,3,3-trifluoropropyl groups, etc., in which some or all of the hydrogen atoms bonded to the carbon atoms of these groups are substituted with halogen atoms such as fluorine, chlorine, bromine, iodine, etc. Among them, methyl and phenyl groups are more preferable in terms of peelability.

[0066] Also, R 1 As a monovalent organic group having 1 to 20 carbon atoms having a hydroxyl group, an amino group, a carboxyl group, an epoxy group, or an isocyanate group, it is preferable to have a structure in which a divalent hydrocarbon group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, is bonded to the hydroxyl group, an amino group, a carboxyl group, an epoxy group, or an isocyanate group, and may include heteroatoms such as oxygen atoms, nitrogen atoms, or fluorine atoms. Here, examples of divalent hydrocarbon groups that may include heteroatoms include alkylene groups such as methylene groups, ethylene groups, propylene groups, butylene groups, pentylene groups, hexylene groups, heptylene groups, octylene groups, arylene groups such as phenylene groups, or combinations of two or more of these groups (alkylene / arylene groups, etc.), and groups in which oxygen atoms are interposed.

[0067] Specifically, as such monovalent organic groups, hydroxyalkyl groups such as 2-hydroxyethyl group, 3-hydroxypropyl group, 2,3-dihydroxypropyl group, 2-hydroxypropyl group, 4-hydroxybutyl group, 2-hydroxybutyl group, 2-(hydroxymethyl)propyl group, 2-hydroxypentyl group, 3-hydroxy-2,2-dimethylpropyl group, 3-hydroxypentyl group, 5-hydroxypentyl group, 6-hydroxyhexyl group, 2-hydroxyhexyl group, 7-hydroxyheptyl group, 8-hydroxyoctyl group, 2-hydroxyethoxy group, 3-[(2-hydroxyethyl)oxy]propyl group, and 3-[(3-hydroxypropyl)oxy]propyl group, etc. -(CH2)3-(OCH2CH2) n1 Polyethylene glycol group represented by -OH (n1 is an integer from 1 to 8), -(CH2)3-(OCH2CH2CH2) n2 Examples include polypropylene glycol groups represented by -OH (n2 is an integer from 1 to 5), 3-aminopropyl groups, N-2-(aminoethyl)-3-aminopropyl groups, carboxyoctyl groups, 3-glycidoxypropyl groups, 2-(3,4-epoxycyclohexyl)ethyl groups, 3-isocyanatepropyl groups, etc. Among these, hydroxyalkyl groups, polyethylene glycol groups, and polypropylene glycol groups are more preferred from the perspective of curability.

[0068] In addition, the above R 1 Among them, there are two or more monovalent organic groups having 1 to 20 carbon atoms, having hydroxyl groups, amino groups, carboxyl groups, epoxy groups, or isocyanate groups, preferably 2 to 4.

[0069] In addition, the above R 1 Of the group, it is preferable that 10 to 60 mol% is an aryl group or an aralkyl group, and more preferable that 15 to 50 mol% is an aryl group or an aralkyl group. If it is within the above range, the peelability becomes better.

[0070] In the above formula (1), a, b, c, and d are such that a is an integer greater than or equal to 2, preferably an integer between 2 and 30, b is an integer greater than or equal to 1, preferably an integer between 1 and 500, c is an integer greater than or equal to 0, preferably an integer between 0 and 10, and d is an integer greater than or equal to 0, preferably an integer between 0 and 10, and 4≤a+b+c+d≤500, and preferably 10≤a+b+c+d≤400.

[0071] (C) Specific examples of the components include, but are not limited to, the following. In addition, Me and Ph in the following formulas represent a methyl group and a phenyl group, respectively.

[0072]

[0073] (2≤e1≤450, 0≤f1≤300, 2≤e1+f1≤498)

[0074]

[0075] (2≤e2≤450, 0≤f2≤300, 2≤e2+f2≤498, 0≤g1≤5, 0≤g2≤5)

[0076]

[0077] (2≤e3≤450, 0≤f3≤300, 0≤h1≤2, 2≤e3+f3+h1≤498)

[0078]

[0079] (2≤e4≤450, 0≤f4≤300, 0≤h2≤2, 2≤e4+f4+h2≤498)

[0080]

[0081] (2≤e5≤450, 0≤f5≤300, 0≤e6≤300, 0≤f6≤300, 0≤e7≤10, 2≤(e5+f5+e6×e7+f6×e7+2×e7)≤498)

[0082] The amount of component (C) is preferably 0.5 to 20 parts by mass per 100 parts by mass of component (A), more preferably 0.5 to 10 parts by mass, and even more preferably 1 to 8 parts by mass. Within the above range, a cured film with excellent peelability is obtained, and the migration of component (C) into the adhesive layer can also be suppressed.

[0083] [(D) Component]

[0084] In the composition of the present invention, an acidic catalyst (D) may be used to promote the cross-linking reaction between component (A), component (B), and component (C). Examples of acidic catalysts include inorganic acids such as hydrochloric acid, sulfuric acid, phosphoric acid, and boric acid; carboxylic acids such as acetic acid, monochloroacetic acid, dichloroacetic acid, and butyric acid; and organic sulfonic acids such as benzenesulfonic acid, p-toluenesulfonic acid, xylenesulfonic acid, p-phenolsulfonic acid, methanesulfonic acid, and ethanesulfonic acid. These acidic catalysts may be used individually or in a suitable combination of two or more.

[0085] (D) When incorporating the component, the amount of the component should be the amount of catalyst that promotes the reaction. For example, 0.1 to 10 parts by mass is preferred for every 100 parts by mass of the total of components (A) to (C), and 0.5 to 5 parts by mass is more preferred. Within the above range, the curability is excellent, and the durability of the cured film is also good.

[0086] [(E) Ingredients]

[0087] A solvent may be incorporated as component (E) into the composition of the present invention. By diluting with a solvent, practical advantages are obtained, such as improved workability of the coating, and improved condition of the coating film, such as the thickness of the coating film or the surface finish.

[0088] Any compound capable of dissolving may be used as a solvent, for example, aromatic hydrocarbon compounds such as toluene and xylene; aliphatic hydrocarbon compounds such as hexane, heptane, and isoparaffin; alcohol compounds such as methanol, ethanol, and 1-butanol; ketone compounds such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; ester compounds such as ethyl acetate and butyl acetate; and ether compounds such as diisopropyl ether and 1,4-dioxane may be used. In the present invention, aromatic hydrocarbon compounds such as toluene and xylene; aliphatic hydrocarbon compounds such as hexane, heptane, and isoparaffin; ketone compounds such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; and ester compounds such as ethyl acetate and butyl acetate; It is more preferable to use ether compounds selected from diisopropyl ether, 1,4-dioxane, etc. These can be used alone or in a suitable combination of two or more.

[0089] (E) When mixing the component, the mixing amount is preferably 100 to 20,000 parts by mass per 100 parts by mass of component (A), and more preferably 200 to 10,000 parts by mass. Within the above range, the coating workability is good, and the surface condition of the film can be improved.

[0090] [Other ingredients]

[0091] In addition to the composition of the present invention, antioxidants, antistatic agents, leveling agents, fillers, defoaming agents, pigments, etc., may be added and blended within a range that does not impair the purpose of the present invention.

[0092] [Method for manufacturing a resin composition for release liner or release film]

[0093] The composition of the present invention may be prepared by mixing components (A) to (C), and optionally component (D), component (E), and optional components. However, when incorporating component (D), it is preferable in terms of preservation stability to uniformly mix component (A), component (B), component (C), optionally component (E), and optional components in advance, and then add component (D) immediately before use. The mixing method is not particularly limited, and known methods may be used.

[0094] [Resin composition for release liner or release film]

[0095] The viscosity of the resin composition for release paper or release film of the present invention at 25°C is preferably 0.1 mPa·s to 10 Pa·s in terms of coating workability, and more preferably 0.2 mPa·s to 5 Pa·s. In addition, the viscosity is measured by a Type B rotational viscometer.

[0096] [Release liner or release film (coating)]

[0097] The present invention provides a release liner or release film having a cured film formed by heating after coating a substrate with the resin composition for the release liner or release film above.

[0098] After preparing the above resin composition for release paper or release film as is, or by diluting it with the solvent of component (E) above to a viscosity suitable for the coating process described below, a coating method such as screen coating, immersion coating, or cast coating is applied using a comma coater, rip coater, roll coater, die coater, knife coater, blade coater, rod coater, kiss coater, gravure coater, wire bar coater, etc., or by using a coating method such as screen coating, immersion coating, or cast coating, with a thickness of 0.01 to 100 g / m² on one or both sides of a sheet-shaped substrate such as paper or film. 2 After coating, a hardened film can be formed on the substrate by heating at 50 to 200°C for 1 to 200 seconds.

[0099] Coating weight 0.01–100 g / m² 2 It is preferable, and 0.03 to 50 g / m²2 It is more preferable that the drying temperature be 50 to 200°C, and more preferably 70 to 180°C. The drying time is preferably 1 to 200 seconds, and more preferably 5 to 90 seconds. In addition, when forming a release layer on both sides of the substrate, it is preferable to perform the curing film formation operation on one side of the substrate.

[0100] Examples of sheet-shaped substrates include various coated papers such as polyethylene laminate paper, glassine paper, high-quality paper, kraft paper, clay-coated paper, and mirror-coated paper, synthetic papers such as synthetic paper, polyethylene film, polypropylene film such as CPP or OPP, polyester film such as polyethylene terephthalate film, polyamide film, polyimide film, polylactic acid film, polyphenol film, and polycarbonate film.

[0101] To improve the adhesion between these substrates and the release layer, a substrate surface that has been corona treated, etched, or plasma treated may be used.

[0102] The resin composition for a release liner or release film of the present invention can form a release film having good releaseability and repeatability, and a gloss equivalent to or greater than that of a conventional release agent composition, in either case of curing at a low temperature (e.g., 40 to 200 seconds at 50 to 150°C) or curing in a short time (e.g., 1 to 40 seconds at 150 to 200°C), compared to the curing conditions of a conventional resin composition for a release liner or release film (e.g., 10 to 200°C).

[0103] Examples

[0104] The present invention will be specifically described below by presenting synthetic examples, examples, and comparative examples, but the present invention is not limited to the following examples.

[0105] Ingredients Used

[0106] (A) Ingredient

[0107] (A1)

[0108] 50 mass% butyl acetate solution of the hydroxyl group-containing acrylic resin obtained in Synthesis Example 1 below

[0109] [Synthesized Example 1]

[0110] 39.6 parts by mass of butyl acetate were charged into a glass reaction apparatus equipped with a stirrer, a thermometer, a reflux condenser, and a dropping device, and after heating to 90–100°C, a mixture of 19.5 parts by mass (0.15 mol) of 2-hydroxyethyl methacrylate, 6.0 parts by mass (0.06 mol) of methyl methacrylate, 33.9 parts by mass (0.10 mol) of stearyl methacrylate, 1.1 parts by mass (0.005 mol) of 2-ethylperoxyhexanoate tert-butyl acetate, and 19.8 parts by mass of butyl acetate was dropped over 4 hours under nitrogen aeration. In addition, after polymerizing at 90–100°C for 2 hours, 0.2 mass parts (0.001 mol) of 2-ethylperoxyhexanoate tert-butyl was added and polymerization was carried out for 2 hours to obtain a 50 mass% butyl acetate solution of a hydroxyl group-containing acrylic resin. The hydroxyl group value of the obtained hydroxyl group-containing acrylic resin was 141 mgKOH / g. The weight-average molecular weight of polystyrene by GPC was 40,000.

[0111] (A2)

[0112] 50 mass% butyl acetate solution of the hydroxyl group-containing acrylic resin obtained in Synthesis Example 2 below

[0113] [Synthesized Example 2]

[0114] 46.1 parts by mass of butyl acetate were charged into a glass reaction apparatus equipped with a stirrer, a thermometer, a reflux condenser, and a dropping device, and after heating to 90–100°C, a mixture of 26.0 parts by mass (0.20 mol) of 2-hydroxyethyl methacrylate, 14.0 parts by mass (0.14 mol) of methyl methacrylate, 29.2 parts by mass (0.28 mol) of styrene, 1.1 parts by mass (0.005 mol) of 2-ethylperoxyhexanoate tert-butyl acetate, and 23.1 parts by mass of butyl acetate was dropped over 4 hours under nitrogen aeration. In addition, after polymerizing at 90–100°C for 2 hours, 0.2 mass parts (0.001 mol) of 2-ethylperoxyhexanoate tert-butyl was added, and polymerization was carried out for 2 hours to obtain a 50 mass% butyl acetate solution of a hydroxyl group-containing acrylic resin. The hydroxyl group value of the obtained hydroxyl group-containing acrylic resin was 161 mgKOH / g. The weight-average molecular weight of polystyrene by GPC was 36,000.

[0115] (A3)

[0116] 50 mass% butyl acetate solution of the hydroxyl group-containing acrylic resin obtained in Synthesis Example 3 below

[0117] [Synthesized Example 3]

[0118] 33.4 parts by mass of butyl acetate were charged into a glass reaction apparatus equipped with a stirrer, a thermometer, a reflux condenser, and a dropping device, and after heating to 90–100°C, a mixture of 20.8 parts by mass (0.16 mol) of 2-hydroxyethyl methacrylate, 15.0 parts by mass (0.15 mol) of methyl methacrylate, 14.2 parts by mass (0.10 mol) of n-butyl methacrylate, 1.1 parts by mass (0.005 mol) of 2-ethylperoxyhexanoate tert-butyl acetate, and 16.7 parts by mass of butyl acetate was dropped over 4 hours under nitrogen aeration. In addition, after polymerizing at 90–100°C for 2 hours, 0.2 mass parts (0.001 mol) of 2-ethylperoxyhexanoate tert-butyl was added and polymerization was carried out for 2 hours to obtain a 50 mass% butyl acetate solution of a hydroxyl group-containing acrylic resin. The hydroxyl group value of the obtained hydroxyl group-containing acrylic resin was 178 mgKOH / g. The weight-average molecular weight of polystyrene by GPC was 44,000.

[0119] (A4)

[0120] 50 mass% butyl acetate solution of the hydroxyl group-containing acrylic resin obtained in Synthesis Example 4 below

[0121] [Synthesized Example 4]

[0122] 36.2 parts by mass of butyl acetate were charged into a glass reaction apparatus equipped with a stirrer, a thermometer, a reflux condenser, and a dropping device, and after heating to 90–100°C, a mixture of 13.0 parts by mass (0.10 mol) of 2-hydroxyethyl methacrylate, 10.0 parts by mass (0.10 mol) of methyl methacrylate, 31.2 parts by mass (0.30 mol) of styrene, 1.1 parts by mass (0.005 mol) of 2-ethylperoxyhexanoate tert-butyl acetate, and 18.1 parts by mass of butyl acetate was dropped over 4 hours under nitrogen aeration. In addition, after polymerizing at 90–100°C for 2 hours, 0.2 mass parts (0.001 mol) of 2-ethylperoxyhexanoate tert-butyl was added and polymerization was carried out for 2 hours to obtain a 50 mass% butyl acetate solution of a hydroxyl group-containing acrylic resin. The hydroxyl group value of the obtained hydroxyl group-containing acrylic resin was 104 mgKOH / g. The weight-average molecular weight of polystyrene by GPC was 43,000.

[0123] (A5)

[0124] 50 mass% butyl acetate solution of the hydroxyl group-containing acrylic resin obtained in Synthesis Example 5 below

[0125] [Synthesized Example 5]

[0126] 45.6 parts by mass of butyl acetate were charged into a glass reaction apparatus equipped with a stirrer, a thermometer, a reflux condenser, and a dropping device, and after heating to 90–100°C, a mixture of 19.5 parts by mass (0.15 mol) of 2-hydroxyethyl methacrylate, 15.0 parts by mass (0.15 mol) of methyl methacrylate, 33.9 parts by mass (0.10 mol) of stearyl methacrylate, 1.1 parts by mass (0.005 mol) of 2-ethylperoxyhexanoate tert-butyl acetate, and 22.8 parts by mass of butyl acetate was dropped over 4 hours under nitrogen aeration. In addition, after polymerizing at 90–100°C for 2 hours, 0.2 mass parts (0.001 mol) of 2-ethylperoxyhexanoate tert-butyl were added, and polymerization was carried out for 2 hours to obtain a 50 mass% butyl acetate solution of a hydroxyl group-containing acrylic resin. The hydroxyl group value of the obtained hydroxyl group-containing acrylic resin was 121 mgKOH / g. The weight-average molecular weight of polystyrene by GPC was 36,000.

[0127] (A6)

[0128] 50 mass% butyl acetate solution of the hydroxyl group-containing acrylic resin obtained in Synthesis Example 6 below

[0129] [Synthesized Example 6]

[0130] 37.3 parts by mass of butyl acetate were charged into a glass reaction apparatus equipped with a stirrer, a thermometer, a reflux condenser, and a dropping device, and after heating to 90–100°C, a mixture of 26.0 parts by mass (0.20 mol) of 2-hydroxyethyl methacrylate, 20.0 parts by mass (0.20 mol) of methyl methacrylate, 10.0 parts by mass (0.07 mol) of n-butyl methacrylate, 1.1 parts by mass (0.005 mol) of 2-ethylperoxyhexanoate tert-butyl acetate, and 18.7 parts by mass of butyl acetate was dropped over 4 hours under nitrogen aeration. In addition, after polymerizing at 90–100°C for 2 hours, 0.2 mass parts (0.001 mol) of 2-ethylperoxyhexanoate tert-butyl was added and polymerization was carried out for 2 hours to obtain a 50 mass% butyl acetate solution of a hydroxyl group-containing acrylic resin. The hydroxyl group value of the obtained hydroxyl group-containing acrylic resin was 198 mgKOH / g. The weight-average molecular weight of polystyrene by GPC was 41,000.

[0131] (A7)

[0132] Alkidia J-524-A (Manufactured by DIC: Palm Oil Modified Alkyd Resin)

[0133] (B) Component

[0134] (B1)

[0135] Cymel 303LF (Manufactured by Allnex Japan Co., Ltd.: Full ether-type methylated melamine resin)

[0136] (C) Component

[0137] (C1)

[0138] Organopolysiloxane represented by the following general formula (2): The order of bonding of each siloxane unit is not limited to the following.

[0139]

[0140] (In the formula, Me is a methyl group and Ph is a phenyl group.)

[0141] (D) Component

[0142] (D1)

[0143] p-toluenesulfonic acid

[0144] (E) Component

[0145] (E1)

[0146] toluene

[0147] [Reference Example 1, Examples 2–3, Comparative Examples 1–4]

[0148] The components (A) to (E) shown above were used as raw materials, and a coating composition was prepared in the following order.

[0149] Components (A), (B), and (C) were placed in a flask according to the mixing ratios in Tables 1 and 2, and component (E) was added so that the solid content of components (A) to (C) was 40 mass%, and the mixture was uniformly mixed. To the obtained solution, component (D) was added in an amount of 2 mass% relative to 100 mass parts of the total of components (A) to (C), and a coating composition was obtained by stirring and mixing. The viscosity of the obtained composition at 25°C, measured by a Type B rotational viscometer, is listed in Tables 1 and 2. Using this composition, a release liner was produced by the method described below.

[0150] [Preparation of Exfoliating Paper]

[0151] The obtained coating composition is applied to a mirror-coated paper with a thickness of 165 μm using a bar coater at an application rate of 7.0 g / m² 2 A release agent layer was formed by applying it to the extent that it was heated in a hot air dryer at 130°C for 60 seconds and in a hot air dryer at 170°C for 30 seconds to obtain a release liner.

[0152] [evaluation]

[0153] Using the release liner obtained above, "peel strength," "surface condition," "gloss," and "repetitive durability" were evaluated by the following method.

[0154] [Peel Strength]

[0155] On the release agent layer of the release liner obtained above, a one-component polyurethane solution [Cris Bone 5516S (manufactured by Dainippon Ink & Chemical Co., Ltd.)] was applied to achieve a film thickness of 30 μm, and heat-treated at 130°C for 2 minutes. Subsequently, a Nitto 31B tape was laminated onto the treated surface and subjected to one reciprocating press with a 2 kg roller. After aging at 25°C for 20 hours, the sample was cut to a width of 3 cm, and the laminated tape was pulled at a peeling speed of 0.3 m / min at an angle of 180° using a tensile testing machine to measure the force required to peel (gf / 30 mm). Additionally, the peel force when heated at 130°C for 60 seconds was denoted as RA, and the peel force when heated at 170°C for 30 seconds was denoted as RB. The smaller the peel strength value, the better the peelability.

[0156] [Surface condition]

[0157] The presence or absence of crawling and stains of the coating film on the release agent layer of the release liner obtained above was evaluated visually. For both the release agent layer cured at 130°C and the release agent layer cured at 170°C, "○" was used when the presence of crawling and stains of the coating film could not be confirmed, and "×" was used when the presence of crawling and stains of the coating film could be confirmed.

[0158] [Gloss]

[0159] Using a gloss meter (VG7000 gloss meter manufactured by Nippon Denshoku Co., Ltd.), the gloss level at an angle of 60° was measured for the release agent layer of the release liner obtained above, which was cured at 170°. A higher value indicates superior gloss.

[0160] [Repetitive Durability]

[0161] On the release agent layer of the release liner obtained above, a one-component polyurethane solution [Crisbon 5516S (manufactured by DIC Co., Ltd.)] was applied to achieve a film thickness of 30 μm, and heat-treated at 130°C for 2 minutes. Subsequently, heat treatment was performed at 180°C for 2 minutes, Nitto 31B tape was laminated onto the treated surface, and peeling was performed after one reciprocating press with a 2 kg roller. This operation was repeated until the release agent layer was removed and could no longer be peeled off, and this was recorded as the number of repeated uses. Additionally, repeatability A represents the number of uses when heated at 130°C for 60 seconds, and repeatability b represents the number of uses when heated at 170°C for 30 seconds. The more uses, the better the repeatability.

[0162] These results are shown in Tables 1 and 2. In addition, regarding the amount of component (A) in the table, the amount including solvent or solution is indicated, and the pure amount of component (A) is indicated in parentheses.

[0163]

[0164]

Claims

Claim 1 A resin composition for release paper or release film comprising (A) a hydroxyl group-containing acrylic resin having a hydroxyl group value greater than 150 mgKOH / g and less than or equal to 180 mgKOH / g, (B) a resin selected from full ether-type methylated melamine resin, methylol-type methylated melamine resin, and polymers thereof, and (C) an organopolysiloxane having two or more hydroxyl groups in one molecule. Claim 2 A resin composition for release paper or release film according to claim 1, characterized in that the weight-average molecular weight of component (A) is 5,000 to 400,000. Claim 3 A resin composition for release paper or release film according to claim 1 or 2, characterized in that the hydroxyl group value of component (A) is 161 to 180 mgKOH / g. Claim 4 A resin composition for a release liner or release film according to claim 1 or 2, characterized in that the amount of component (B) is 10 to 120 parts by mass per 100 parts by mass of component (A). Claim 5 A resin composition for a release liner or release film according to claim 1 or 2, characterized in that (B) the component is a resin selected from a full ether-type methylated melamine resin and a polymer thereof. Claim 6 A resin composition for a release liner or release film according to claim 1 or 2, characterized in that the amount of component (C) is 0.5 to 20 parts by mass per 100 parts by mass of component (A). Claim 7 A resin composition for a release liner or release film according to claim 1 or 2, characterized in that (C) the component comprises an organopolysiloxane in which 10 to 60 mol% of the organic group bonded to a silicon atom in one molecule is a phenyl group. Claim 8 A resin composition for a release liner or release film according to claim 1 or 2, characterized in that it further comprises (D) an acidic catalyst. Claim 9 A release liner or release film having a cured film formed by heating after coating a substrate with the resin composition for a release liner or release film described in claim 1 or 2. Claim 10 delete

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