Addition-curable release silicone composition for silicone pressure-sensitive adhesive, release film, and release paper

Abstract

The present invention is an addition-curable mold-release silicone composition for a silicone pressure-sensitive adhesive, the composition containing: (A) a fluorine-containing organopolysiloxane having at least two alkenyl groups and at least one fluorine-containing substituent, and having at least one aryl group and / or aralkyl group, the fluorine content being 25-50 mass%, and the fluorine content being 1-20 mass%; the ratio of the total number of aryl groups and aralkyl groups with respect to the total number of monovalent substituents is 0.1-20 mol%, and the area of components having a molecular weight of 4,000 or less is 2-20% of the total peak area in molecular weight distribution measurement; (B) an organohydrogenpolysiloxane having at least three SiH groups; (C) a platinum group metal catalyst; and (D) a non-fluorine solvent. As a result, provided is a silicone composition for a release agent, which can be diluted with a non-fluorine solvent, has high coatability and adhesion to a film substrate, and is capable of obtaining a cured coating film that has a small release force and a small decrease in residual adhesive force when evaluated by a transfer method.

Description

Technical Field

[0001] The present invention relates to an addition-curable release silicone composition for silicone pressure-sensitive adhesives, which can be diluted with a non-fluorine solvent (i.e., an organic solvent without fluorine atoms in its molecule) headed by a non-halogen solvent (i.e., an organic solvent without halogen atoms in its molecule), and which exhibits good release properties for silicone pressure-sensitive adhesives, especially when evaluated by a transfer method, and has excellent transparency and adhesion. Background Art

[0002] Conventionally, in order to prevent adhesion or fixation between a substrate such as paper or plastic film and a pressure-sensitive adhesive such as a silicone pressure-sensitive adhesive, a cured film of a silicone composition is formed on the outer surface of the substrate to impart releasability to the pressure-sensitive adhesive. This cured film is generally called release paper.

[0003] Among the above-mentioned pressure-sensitive adhesive materials, silicone pressure-sensitive adhesives mainly composed of organopolysiloxane have been used in a wide range of applications due to their excellent heat resistance, cold resistance, chemical resistance, electrical insulation, low toxicity, etc. Since silicone pressure-sensitive adhesives have very strong adhesion, in order to easily peel the pressure-sensitive adhesive tape or pressure-sensitive adhesive label coated with the silicone pressure-sensitive adhesive from the above-mentioned substrate, the silicone cured film formed on the above-mentioned substrate needs to be a releasable film.

[0004] Patent Document 1 discloses an organopolysiloxane composition as an organosilicone composition capable of obtaining an organosilicone cured film with excellent mold release properties. n F 2n+1 CH 2 CH 2 - (n is an integer greater than 1) represented by a fluorine-containing substituent. In addition, Patent Document 2 proposes an organopolysiloxane composition having a fluorine-containing substituent represented by F-[CF(CF 3 )CF 2 O] n CF(CF 3 )CF 2 OCH 2 CH 2 CH 2 -(n is an integer of 1 to 5).

[0005] When these organopolysiloxane compositions are applied to a substrate, they are diluted with an organic solvent. In this case, a fluorinated solvent (i.e., an organic solvent having a fluorine atom in the molecule) is preferably used as the organic solvent from the viewpoint of the solubility of the fluorinated organopolysiloxane composition and the coating properties on the substrate.

[0006] However, although fluorinated solvents can sufficiently dilute fluorinated organopolysiloxanes, they are expensive and have problems of adversely affecting the natural environment when diffused into the atmosphere.

[0007] Patent Document 3 proposes a silicone composition for release paper having a fluorine-containing substituent as a silicone composition that can be diluted with a non-fluorine-containing solvent and can provide a cured silicone film having excellent releasability.

[0008] However, when the silicone composition for release agent is dissolved in a non-fluorine-based solvent, there is a tendency that the peeling force is higher than when diluted with a fluorine-based solvent. In addition, although there is no record of coating properties and adhesion in Patent Document 3, when the silicone composition for release paper is dissolved in a non-fluorine-based solvent, the coating property on the substrate may be poorer than when diluted with a fluorine-based solvent. If the coating property on the substrate is poor, the part of the substrate not covered by the silicone composition for release agent will contact the pressure-sensitive adhesive and the peeling force will be significantly increased.

[0009] In addition, the silicone composition coating for release paper obtained by dissolving the silicone composition in a non-fluorine-containing solvent may have low adhesion to the film substrate, and the release layer may peel off from the substrate over time.

[0010] Patent Document 4 proposes a method of adding a linear perfluoropolyether defoaming agent to a silicone composition for a release agent as a method for improving coating properties. However, the linear perfluoropolyether defoaming agent does not have a reactive functional group and therefore does not participate in crosslinking. It may sometimes transfer to the pressure-sensitive adhesive layer side when the pressure-sensitive adhesive is peeled off, thereby reducing the residual adhesive force.

[0011] In the above patent document, as a method for evaluating the peeling property, a tape having a pressure-sensitive adhesive layer is attached to a release layer and the force at the time of peeling is evaluated (tape method), but the following evaluation is not performed: the pressure-sensitive adhesive is cured on the release layer and a substrate is attached from above and the force at the time of peeling is evaluated (transfer method). The transfer method is a method used when forming a pressure-sensitive adhesive layer on a substrate with low heat resistance, and the force required for peeling tends to be higher than that of the tape method.

[0012] In order to improve the adhesion, it is known to add a functional compound that interacts with the substrate. However, the compatibility between the substrate functional compound and the silicone composition is low, so the composition formed by adding the substrate functional compound to the silicone composition will produce the problem of separation of the substrate functional compound during long-term storage and transportation. If the separated composition is used directly, there is a possibility that the original performance cannot be obtained. In addition, the substrate functional compound sometimes transfers to the pressure-sensitive adhesive layer side when the pressure-sensitive adhesive is peeled off, causing the residual adhesion to decrease.

[0013] As described above, there is no known release silicone composition for pressure-sensitive adhesives in the prior art, which can be diluted with a non-fluorinated solvent and has sufficient coating properties to completely cover the substrate, adhesion to the substrate without falling off over time, releasability to show easy peeling even when evaluating a pressure-sensitive adhesive with high adhesive strength by a transfer method, and residual adhesive strength.

[0014] Prior art literature

[0015] Patent Literature

[0016] Patent Document 1: Japanese Patent Publication No. 5-7434

[0017] Patent Document 2: Japanese Patent Publication No. 4-76391

[0018] Patent Document 3: Japanese Patent Application Laid-Open No. 7-18185

[0019] Patent Document 4: Japanese Patent Application Publication No. 2004-300414 Summary of the invention

[0020] 1. Technical issues to be resolved

[0021] The present invention has been completed in view of the above situation, and its purpose is to provide a silicone composition for a release agent, which can be diluted with a non-fluorine-based solvent, has high coating properties and adhesion to a film substrate, and can obtain a cured film with a small peeling force and a small decrease in residual adhesive force when evaluated by a transfer method.

[0022] (II) Technical solution

[0023] In order to solve the above technical problems, the present invention provides an addition-curable release silicone composition for silicone pressure-sensitive adhesive, which contains:

[0024] (A) a fluorine-containing organopolysiloxane having in one molecule at least two alkenyl groups bonded to silicon atoms and at least one fluorine-containing substituent bonded to silicon atoms, and at least one aryl group and / or aralkyl group bonded to silicon atoms, wherein the fluorine content is 25 to 50% by mass, and the ratio of the total number of the aryl groups and the aralkyl groups to the total number of monovalent substituents bonded to silicon atoms is 0.1 to 20 mol %, and in a molecular weight distribution measurement obtained by gel permeation chromatography, the area of ​​components having a molecular weight of 4,000 or less is 2 to 20% of the total peak area, wherein the (A) fluorine-containing organopolysiloxane is 100 parts by mass;

[0025] (B) an organohydrogenpolysiloxane having at least three hydrogen atoms (SiH groups) bonded to silicon atoms in one molecule, wherein the molar ratio of the hydrogen atoms (SiH groups) bonded to silicon atoms in the component (B) to the alkenyl groups in the component (A) is 0.1 to 15;

[0026] (C) a platinum group metal catalyst, in an amount of 0.5 to 5,000 ppm based on the mass of the platinum group metal relative to the component (A); and

[0027] (D) a non-fluorinated solvent in an amount of 100 to 20,000 parts by mass.

[0028] If it is such an addition-curable release silicone composition for silicone pressure-sensitive adhesives, it is possible to provide a silicone composition for release agents that can be diluted with a non-fluorine-based solvent, has high coating properties and adhesion to a film substrate, and can obtain a cured film that has a small peel force when evaluated by a transfer method and a small decrease in residual adhesive strength.

[0029] Furthermore, the molar ratio of hydrogen atoms (SiH groups) bonded to silicon atoms in the component (B) to alkenyl groups in the component (A) is preferably 0.5 to 5.

[0030] With such an addition-curable releasable silicone composition for silicone pressure-sensitive adhesives, it is possible to provide a silicone composition for a release agent having better coating properties, adhesion properties, and releasability.

[0031] In the component (B), the ratio of the total number of aryl groups and aralkyl groups to the total number of monovalent substituents bonded to silicon atoms is preferably 0 to 50 mol %.

[0032] With such an addition-curable releasable silicone composition for silicone pressure-sensitive adhesives, it is possible to provide a silicone composition for a release agent having better coating properties, adhesion properties, and releasability.

[0033] Furthermore, it is preferred that the component (D) is a non-fluorinated solvent having an SP value of 10.0 or less.

[0034] According to such an addition-curable releasable silicone composition for silicone pressure-sensitive adhesives, it is possible to provide a silicone composition for a release agent in which the component (A) is more well dissolved.

[0035] Furthermore, it is preferred that the component (D) is at least one selected from the group consisting of hydrocarbon solvents, ketone solvents, ether solvents, and ester solvents.

[0036] Such an addition-curable releasable silicone composition for silicone pressure-sensitive adhesives can provide a silicone composition for a release agent in which the component (A) can be dissolved more satisfactorily.

[0037] The present invention also provides a release film having a cured product layer of the addition-curable releasable silicone composition for a silicone pressure-sensitive adhesive formed on at least one outer surface of a film substrate.

[0038] With such a release film, a release film having excellent releasability can be provided.

[0039] The present invention also provides a release paper having a cured product layer of the addition-curable release silicone composition for silicone pressure-sensitive adhesives formed on at least one outer surface of a paper substrate.

[0040] Such a release paper can provide a release paper having excellent releasability.

[0041] (III) Beneficial effects

[0042] As described above, according to the present invention, it is possible to provide a silicone composition for a release agent that can be diluted with a non-fluorinated solvent, has high coating properties and adhesion to a film substrate, and can obtain a cured film having a small peeling force when evaluated by a transfer method and a small decrease in residual adhesive strength. DETAILED DESCRIPTION

[0043] As described above, there is a need to develop a silicone composition for a release agent that can be diluted with a non-fluorinated solvent, has high coating properties and adhesion to a film substrate, and can provide a cured film having a small peeling force and a small decrease in residual adhesive strength when specifically evaluated by a transfer method.

[0044] The inventors of the present application have conducted intensive research to achieve the above-mentioned purpose, and as a result, have found that by blending the above-mentioned (A) to (D) components in a specific ratio, a silicone composition for a release agent can be obtained, which has high coating properties and adhesion to a film substrate, and can obtain a cured film with a small peeling force and a small decrease in residual adhesion when evaluated by a transfer method. Furthermore, since the composition does not contain fluorine-based solvents, it is low-cost and has no concerns about air pollution. A release silicone cured film can be produced, and the cured film is excellent in hydrophobicity, oleophobicity, and heat resistance, thereby completing the present invention.

[0045] That is, the present invention is an addition-curable release silicone composition for silicone pressure-sensitive adhesives, comprising:

[0046] (A) a fluorine-containing organopolysiloxane having in one molecule at least two alkenyl groups bonded to silicon atoms and at least one fluorine-containing substituent bonded to silicon atoms, and at least one aryl group and / or aralkyl group bonded to silicon atoms, wherein the fluorine content is 25 to 50% by mass, and the ratio of the total number of the aryl groups and the aralkyl groups to the total number of monovalent substituents bonded to silicon atoms is 0.1 to 20 mol %, and in a molecular weight distribution measurement by gel permeation chromatography, the area of ​​components having a molecular weight of 4,000 or less is 2 to 20% of the total peak area, wherein the fluorine-containing organopolysiloxane (A) is 100 parts by mass;

[0047] (B) an organohydrogenpolysiloxane having at least three hydrogen atoms (SiH groups) bonded to silicon atoms in one molecule, wherein the molar ratio of the hydrogen atoms (SiH groups) bonded to silicon atoms in the component (B) to the alkenyl groups in the component (A) is 0.1 to 15;

[0048] (C) a platinum group metal catalyst, the amount of which is 0.5 to 5,000 ppm based on the mass of the platinum group metal relative to the component (A); and

[0049] (D) a non-fluorinated solvent in an amount of 100 to 20,000 parts by mass.

[0050] The present invention will be described in more detail below, but the present invention is not limited thereto.

[0051] [(A) ingredient]

[0052] The component (A) in the present invention is a fluorine-containing organopolysiloxane having at least two alkenyl groups bonded to silicon atoms and at least one fluorine-containing substituent bonded to silicon atoms in one molecule, and at least one aryl group and / or aralkyl group bonded to silicon atoms, wherein the fluorine content is 25 to 50% by mass, and the ratio of the total number of the aryl groups and the aralkyl groups to the total number of monovalent substituents bonded to silicon atoms is 0.1 to 20 mol %, and in the molecular weight distribution measurement obtained by gel permeation chromatography analysis, the area of ​​the component having a molecular weight of 4,000 or less is 2 to 20% of the total peak area, and the fluorine-containing organopolysiloxane functions as a main agent (base polymer) of the addition-curable release silicone composition for silicone pressure-sensitive adhesives of the present invention.

[0053] The fluorinated organopolysiloxane of component (A) may be either linear or branched. In particular, a linear fluorinated organopolysiloxane represented by the following formula (1) is preferably used, wherein the main chain of the molecular chain is composed of a repetition of a difunctional diorganosiloxane unit and must contain a diorganosiloxane unit having a fluorinated substituent bonded to a silicon atom (i.e., a monovalent hydrocarbon group in which a part or all of the hydrogen atoms bonded to a carbon atom are substituted with fluorine atoms and may contain an ether-bonded oxygen atom (-O-)), and A diorganosiloxane unit having an aryl group and / or an aralkyl group bonded to a silicon atom as the diorganosiloxane unit in the main chain, wherein both ends of the molecular chain are capped with a triorganosiloxy group having an alkenyl group (alkenyldiorganosiloxy, dienylorganosiloxy, or trialnylsiloxy) and the molecule has at least two alkenyl groups bonded to silicon atoms at both ends of the molecular chain, or the molecule has at least two alkenyl groups bonded to silicon atoms at both ends of the molecular chain and silicon atoms at non-terminal ends of the molecular chain (in the molecular chain). In the following formula (1), the arrangement of the diorganosiloxane units in the main chain may be random.

[0054] [Chemical formula 1]

[0055]

[0056] Here, R 1 It is an alkenyl group having 2 to 10 carbon atoms, and specific examples thereof include vinyl, allyl, propenyl, isopropenyl, butenyl, isobutenyl, hexenyl, and cyclohexenyl.

[0057] R 2 The unsubstituted or substituted aliphatic monovalent hydrocarbon group having 1 to 10 carbon atoms other than an aliphatic unsaturated group, specifically, alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, hexyl, cyclohexyl, heptyl, octyl, 2-ethylhexyl, nonyl and decyl; and hydroxypropyl and cyanoethyl groups in which a part or all of the hydrogen atoms of these groups are substituted with hydroxyl, cyano or the like.

[0058] R 3 R is an aryl group such as phenyl, tolyl, or an aralkyl group such as benzyl, phenethyl, etc. 3’ For R 3 or R 2 .

[0059] In the above formula, a is 1, 2 or 3, w, x, y, z are respectively an integer of w≥1, an integer of x≥0, an integer of y≥0, and an integer of z≥1, preferably w is an integer of 10 to 300, x is an integer of 0 to 20, y is an integer of 50 to 800, and z is an integer of 1 to 150, more preferably w is an integer of 20 to 200, x is an integer of 0 to 10, y is an integer of 100 to 400, and z is an integer of 5 to 100, so that the fluorine content in the molecule is 25 to 50% by mass and the ratio of the total number of the above aryl groups and the above aralkyl groups in the molecule to the total number of monovalent substituents bonded to the silicon atom (that is, relative to R 1 , R 2 , R 3 , R 3’ The sum of R and Rf 3 The ratio (just, for R 3’ =R 2 ) or R 3 +R 3’ The total ratio (only, for R 3’ =R 3 In the case of ()), the value of w+x+y+z is appropriately controlled in a manner of 0.1 to 20 mol %.

[0060] In formula (1), the fluorine-containing substituent represented by Rf (i.e., a monovalent hydrocarbon group that may contain an ether-bonded oxygen atom (-O-) in which a part or all of the hydrogen atoms bonded to the carbon atom are substituted by fluorine atoms) may be exemplified by a monovalent fluorine-containing substituent represented by the following formula (2) (i.e., a perfluoroalkyl group, a polyfluoroalkyl group, a perfluorooxyalkyl group (monovalent perfluoropolyether group) or a polyfluorooxyalkyl group (monovalent polyfluoropolyether group)).

[0061] Formula (2):

[0062]

[0063] In formula (2), b1 to b24 are integers greater than 0; however, at least one of b1 to b22 is an integer greater than 1; the total of b1 to b22 is preferably less than 25, and the total of b23 and b24 is preferably less than 8; n1 to n65 are each independently 0, 1 or 2; and X is an oxygen atom or a single bond.

[0064] In the above formula, the repeating units on the left side of "-X-" may be randomly bonded to each other, and the repeating units on the right side of "-X-" [CF(CF 3 )] unit and (CH n65 F 2-n65 ) units may also be randomly bonded.

[0065] The fluorine-containing (poly)ether organic group (perfluorooxyalkyl group or polyfluorooxyalkyl group) in the fluorine-containing substituent represented by Rf is more preferably a group represented by any of the following formulas (3), (4) or (5).

[0066]

[0067] In formula (3), c1 to c4 are integers greater than 0, c1+c2 is an integer greater than 1, and c3+c4 is an integer greater than 0; c1+c2 is preferably 25 or less, more preferably 15 or less, and further preferably 9 or less. c3+c4 is preferably 8 or less; in addition, F[CF(CF 3 )CF 2 O] c1 [CF(CF 3 )CH 2 O] c2 (CF 2 ) c3 (CH 2 ) c4 -The repeating units in each may be randomly bonded.

[0068]

[0069] In formula (4), d1 to d6 are integers greater than 0, d1+d2+d3+d4 are integers greater than 1; d1+d2+d3+d4 is preferably 25 or less, more preferably 15 or less, and further preferably 9 or less; d6 is preferably 8 or less; and F(CF 2 O) d1 (CF 2 CF 2 O) d2 (CF 2 CF 2 CF 2 O) d3 [CF(CF 3 )CF 2 O] d4 (CF 2 ) d5 The repeating units in the group may be randomly bonded.

[0070]

[0071] In formula (5), e1 and e2 are respectively integers greater than 1, and e3 is an integer greater than 0; e1 is preferably less than 8, and e2 and e3 are respectively preferably less than 6.

[0072] As particularly preferred fluorine-containing (poly)ether organic groups, the following groups can be exemplified.

[0073]

[0074] In the above formula, f is preferably 1 to 20, more preferably 2 to 12, and most preferably 3 to 9. g+h is preferably 1 to 20, more preferably 2 to 12, and most preferably 3 to 9. i is preferably 15 or less, more preferably 10 or less, and most preferably 6 or less.

[0075] Specific examples of the fluorinated organopolysiloxane of the component (A) include those represented by the following formulae.

[0076] [Chemical formula 2]

[0077]

[0078] [Chemical formula 3]

[0079]

[0080] [Chemical formula 4]

[0081]

[0082] In the formula, Rf, w, x, y and z have the same meanings as above, Me represents a methyl group, Ph represents a phenyl group, and Vi represents a vinyl group.

[0083] The fluorine-containing organopolysiloxane of component (A) needs to have a fluorine content in the molecule of 25 to 50% by mass, preferably 30 to 48% by mass, and more preferably 35 to 46% by mass. If the fluorine content in component (A) is less than 25% by mass, the peel strength of the obtained cured film to the silicone pressure-sensitive adhesive is improved. If it is more than 50% by mass, it is insoluble in non-fluorine-containing solvents.

[0084] In addition, the fluorinated organopolysiloxane of the component (A) needs to have a ratio of the total number of the above-mentioned aryl groups and the above-mentioned aralkyl groups to the total number of the monovalent substituents bonded to the silicon atoms of 0.1 to 20 mol%. If the ratio is less than 0.1 mol%, severe peeling will occur when evaluating the release properties of the silicone pressure-sensitive adhesive by the transfer method. If it is more than 20 mol%, the adhesion to the substrate will be significantly reduced.

[0085] Furthermore, the fluorinated organopolysiloxane of the component (A) needs to be one in which the area of ​​components having a molecular weight of 4,000 or less (e.g., components having a molecular weight of more than 0 and 4,000 or less) accounts for 2 to 20% of the total peak area in a molecular weight distribution measurement obtained by gel permeation chromatography (GPC) analysis. A substance in which the area of ​​components having a molecular weight of 4,000 or less accounts for less than 2% of the total peak area in the GPC analysis has poor solubility in non-fluorinated solvents and poor coating properties on substrates, and a substance in which the area of ​​components having a molecular weight of more than 20% accounts for poor adhesion to substrates and a large decrease in residual adhesiveness.

[0086] In the present invention, the area ratio of components having a molecular weight of 4,000 or less refers to, for example, the ratio (%) of the peak area of ​​components in the lower molecular weight region with a peak corresponding to a molecular weight of 4,000 as a boundary, to the peak area of ​​all components (total peak area) in a molecular weight distribution measurement obtained by gel permeation chromatography (GPC) using a fluorinated solvent such as hydrochlorofluorocarbon (HCFC)-225 as an elution solvent and polymethyl methacrylate (PMMA) as a standard sample.

[0087] The fluorinated organopolysiloxane of the component (A) may be used alone or in combination of two or more.

[0088] [(B) ingredient]

[0089] The organohydrogenpolysiloxane of the component (B) has at least three hydrogen atoms (SiH groups) bonded to silicon atoms in one molecule, and the SiH groups undergo a hydrosilylation addition reaction with the alkenyl groups in the component (A) to form a cured film by crosslinking and curing.

[0090] The organohydrogenpolysiloxane as the component (B) may be any of a linear, cyclic, branched, or three-dimensional network structure, and may be a substance (fluorinated organohydrogenpolysiloxane) having in its molecule a fluorine-containing substituent (i.e., a monovalent hydrocarbon group containing an ether-bonded oxygen atom (-O-) in which a part or all of the hydrogen atoms bonded to the carbon atom are substituted with fluorine atoms) the same as Rf in the formula (1) of the component (A). For example, a linear organohydrogenpolysiloxane represented by the following formula (i.e., an organo(hydrogen)polysiloxane terminated with triorganosiloxy groups at both ends of the molecular chain, a diorganosiloxane-organo(hydrogen)siloxane copolymer terminated with triorganosiloxy groups at both ends of the molecular chain, a diorganopolysiloxane terminated with diorgano(hydrogen)siloxy groups at both ends of the molecular chain, or a diorganopolysiloxane terminated with diorgano(hydrogen)siloxy groups at both ends of the molecular chain) is preferably used. An organo(hydrogen)polysiloxane terminated with a diorgano(hydrogen)siloxane alkoxy group, or a diorganosiloxane-organo(hydrogen)siloxane copolymer terminated with diorgano(hydrogen)siloxane alkoxy groups at both ends of the molecular chain, wherein the main chain of the molecular chain is composed of a repeating structure of a difunctional organo(hydrogen)siloxane unit or a copolymer of a difunctional organo(hydrogen)siloxane unit and a difunctional diorganosiloxane unit, and both ends of the molecular chain are terminated with a triorganosiloxane alkoxy group or a diorgano(hydrogen)siloxane alkoxy group, and the molecule has at least 3 hydrogen atoms (SiH groups) bonded to silicon atoms at non-terminal ends of the molecular chain (in the molecular chain), or a total of at least 3 hydrogen atoms (SiH groups) bonded to silicon atoms at non-terminal ends of the molecular chain (in the molecular chain) and hydrogen atoms (SiH groups) bonded to silicon atoms at both ends of the molecular chain in one molecule.

[0091] [Chemical formula 5]

[0092]

[0093] In the above formula, R 4 is selected from R in the above formula (1) 2 and at least one group of the same group as Rf, R 5 is selected from R in the above formula (1) 3 At least one group in the same group, j is 0 or 1, p, q and r are respectively an integer of p≥1, an integer of q≥0, and an integer of r≥0, preferably p is an integer of 3 to 150, q is an integer of 0 to 150, and r is an integer of 0 to 75, more preferably p is an integer of 10 to 100, q is an integer of 10 to 100, and r is an integer of 0 to 50; wherein p is a number that makes the number of hydrogen atoms (SiH groups) bonded to silicon atoms in the molecule 3 or more.

[0094] Specific examples of the organohydrogenpolysiloxane of the component (B) include those represented by the following formula.

[0095] [Chemical formula 6]

[0096]

[0097] [Chemical formula 7]

[0098]

[0099] In the formula, Me represents a methyl group, Ph represents a phenyl group, Rf, p and q have the same meanings as above, q' is an integer of 1 to 100, r is an integer of 1 to 50, and q'+r is an integer of 2 to 150.

[0100] The amount of the organohydrogenpolysiloxane of the component (B) is such that the molar ratio of hydrogen atoms bonded to silicon atoms (SiH groups) in the component (B) to the alkenyl groups in the component (A) is 0.1 to 15 (mol / mol), preferably 0.3 to 10, and more preferably 0.5 to 5. When the molar ratio of SiH groups in the component (B) to the alkenyl groups in the component (A) is less than 0.1 or greater than 15, the curability of the desired addition-curable release silicone composition for silicone pressure-sensitive adhesives is reduced, or the physical properties of the cured product are reduced.

[0101] In the organohydrogenpolysiloxane of the component (B), the ratio of the total number of aryl groups and aralkyl groups to the total number of monovalent substituents bonded to silicon atoms is preferably 0 to 50 mol%, particularly preferably 0 to 35 mol%, and further preferably 0 to 20 mol%. When the ratio of the total number of aryl groups and aralkyl groups to the total number of monovalent substituents bonded to silicon atoms in the organohydrogenpolysiloxane of the component (B) is 50 mol% or less, the compatibility with the component (A) is good, and the curability of the target addition-curable release silicone composition for silicone pressure-sensitive adhesives and the physical properties of the cured product are also good.

[0102] The organohydrogenpolysiloxane of the component (B) may be used alone or in combination of two or more.

[0103] [(C) ingredient]

[0104] The platinum group metal catalyst of component (C) is a catalyst for promoting the hydrosilylation addition reaction of the alkenyl group in component (A) and the SiH group in component (B), and a substance known as a reaction catalyst can be used. As such a platinum group metal catalyst, catalysts such as platinum, palladium, and rhodium can be listed, among which platinum catalysts are particularly preferred. As such a platinum catalyst, chloroplatinic acid, an alcohol solution of chloroplatinic acid, a complex of chloroplatinic acid and various olefins or vinyl siloxanes, etc. can be listed.

[0105] The amount of these platinum group metal catalysts added is only a catalytic amount. From the perspective of reactivity and economic efficiency when obtaining a cured film, it is 0.5 to 5,000 ppm, preferably 1 to 1,000 ppm, and more preferably 5 to 300 ppm, relative to the mass of the platinum group metal of component (A). If it is less than 0.5 ppm, the curability decreases or the substrate adhesion decreases. If it exceeds 5,000 ppm, the pot life of the treatment bath becomes shorter.

[0106] [(D) ingredient]

[0107] (D) component is a fluorine-free solvent (i.e., an organic solvent having no fluorine atoms in the molecule), and the SP value of the fluorine-free solvent is preferably 10.0 or less, more preferably 9.5 or less, and even more preferably 9.0 or less. If the SP value of the fluorine-free solvent of component (D) is 10.0 or less, the fluorine-containing organopolysiloxane of component (A) can be fully dissolved. In addition, the lower limit of the SP value is not particularly limited, and can be, for example, 5.0 or more, preferably 6.0 or more, and more preferably 7.0 or more.

[0108] The non-fluorinated solvent of component (D) is preferably a hydrocarbon solvent, a ketone solvent, an ether solvent or an ester solvent, and specific examples thereof include hexane, heptane, octane, isooctane, nonane, isononane, decane, cyclohexane, methylcyclohexane, naphtha, aliphatic hydrocarbon solvents such as benzine, petroleum ether (ligroin), industrial gasoline, and naphtha solvents; aromatic hydrocarbon solvents such as toluene and xylene; ketone solvents such as acetone, methyl ethyl ketone, 2-pentanone, 3-pentanone, 2-hexanone, 3-hexanone, 2-heptanone, 3-heptanone, 4-heptanone, methyl isobutyl ketone, diisobutyl ketone, and cyclohexanone; ester solvents such as methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, isobutyl acetate, and methyl propionate; ether solvents such as diethyl ether, dipropyl ether, diisopropyl ether, dibutyl ether, 1,2-dimethoxyethane, and 1,4-dioxane, etc., which can be used alone or in combination of two or more.

[0109] The amount of the non-halogen solvent as component (D) is preferably such an amount that the viscosity of the silicone composition after dilution is 100 cp or less, from the viewpoint of workability when applying the silicone composition dissolved using the component and ease of controlling the coating amount, and is 100 to 20,000 parts by mass, preferably 500 to 15,000 parts by mass, more preferably 800 to 12,000 parts by mass, and even more preferably 1,000 to 3,000 parts by mass based on 100 parts by mass of component (A).

[0110] [Other ingredients]

[0111] The addition-curable release silicone composition for silicone pressure-sensitive adhesive of the present invention is obtained by blending a certain amount of the above-mentioned components (A) to (D), but in addition to the above-mentioned components, other arbitrary components can be added. For example, in order to control the catalyst activity of the platinum group metal catalyst, various organic nitrogen compounds, organic phosphorus compounds, organic silicon compounds, acetylene compounds, oxime compounds and other activity control agents can be added. Among the activity control agents, acetylene compounds such as 3-methyl-1-butyn-3-ol and their silylates, divinyltetramethyldisiloxane, tetravinyltetramethylcyclotetrasiloxane and other silicon compounds are suitable.

[0112] The amount of the activity control agent added is preferably 0.05 to 3 parts relative to 100 parts of component (A). If it is 0.05 parts or more, the target silicone composition will not gel, and if it is 3 parts or less, it will not hinder the curing of the silicone composition. In addition, the amount of other optional components added can be set to a conventional amount according to the purpose.

[0113] [Preparation of addition-curable release silicone composition for silicone pressure-sensitive adhesive]

[0114] When preparing the addition-curable release silicone composition for the silicone pressure-sensitive adhesive of the present invention, it is preferred to uniformly mix the components (A), (B) and (D) in advance and then add the component (C) immediately before use. Each component may be used alone or in combination of two or more.

[0115] [Silicone curing film]

[0116] As the substrate for coating the addition-curable release silicone composition for the silicone pressure-sensitive adhesive of the present invention, paper, plastic film, metal, cloth, glass, etc. can be selected. As plastic film, polyester, polypropylene, polyethylene, polystyrene, polycarbonate, polyvinyl alcohol, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, polyvinyl chloride, polyvinylidene chloride, polytetrafluoroethylene, polyimide, polyamide, polyphenylene sulfide, etc. can be listed. As paper, paper substrates such as glass paper, kraft paper, and clay-coated paper can be listed; laminated paper substrates such as polyethylene laminated high-grade paper and polyethylene laminated kraft paper can be listed. As metal, aluminum foil, copper foil, gold foil, silver foil, etc. can be listed. As cloth, natural fiber cloth, synthetic fiber cloth, artificial leather, etc. can be listed. Glass has no particular restrictions on thickness or type, and can be glass that has been subjected to chemical strengthening treatment, surface treatment, etc., and glass fiber can also be applied.

[0117] As a method for coating the addition-curable release silicone composition for the silicone pressure-sensitive adhesive of the present invention on these substrates, known methods such as a rod coater, a roll coater, a gravure coater, a knife coater, a blade coater, a spin coater, dip coating, and cast coating can be used.

[0118] As the curing conditions of the addition-curable release silicone composition for the silicone pressure-sensitive adhesive of the present invention, there are methods such as heating the substrate coated with the silicone composition at a temperature of 80 to 250° C. for 1 to 120 seconds, or curing it by irradiating ultraviolet rays from an ultraviolet irradiation device such as a high-pressure mercury lamp for 0.2 seconds or more after volatilizing the above-mentioned non-halogen solvent, but it is not limited to this.

[0119] The addition-curable release silicone composition for silicone pressure-sensitive adhesives of the present invention can obtain a cured film having excellent coating properties, adhesion and release properties to a substrate, and is therefore suitable for use in pressure-sensitive adhesive tapes and release papers for pressure-sensitive adhesive labels. It can also be suitable for use as a release agent for molds for molding rubber, plastics, etc., a fiber treatment agent for paper, cloth, etc., a water-repellent agent, an oil-repellent agent, and a heat-resistant coating for food packaging.

[0120] [Release film]

[0121] Therefore, the present invention provides a release film having a cured layer of the addition-curable release silicone composition for silicone pressure-sensitive adhesives formed on at least one outer surface of a film substrate. Such a release film can provide a release film having excellent release properties.

[0122] [Release paper]

[0123] The present invention also provides a release paper having a cured product layer of the addition-curable release silicone composition for silicone pressure-sensitive adhesives formed on at least one outer surface of a paper substrate. Such a release paper can provide a release paper having excellent release properties.

[0124] Example

[0125] The present invention will be specifically described below with reference to synthesis examples, examples and comparative examples, but the present invention is not limited to the following examples. In addition, "parts" means "parts by mass".

[0126] [Molecular weight distribution measurement]

[0127] The molecular weight distribution of the fluorinated organopolysiloxane of component (A) was measured by gel permeation chromatography (GPC) under the following conditions. For each fluorinated organopolysiloxane, the ratio (%) of the area of ​​components having a molecular weight of 4,000 or less to the total peak area in the molecular weight distribution measurement by GPC was calculated.

[0128] [Measurement conditions]

[0129] Elution solvent: Hydrochlorofluorocarbon (HCFC)-225

[0130] Flow rate: 1 mL / min

[0131] Detector: Evaporative light scattering detector

[0132] Chromatographic columns: 2 TSKgel Multipore HXL-M (7.8 mm φ × 30 cm) manufactured by TOSOH CORPORATION

[0133] Column temperature: 35°C

[0134] Sample injection volume: 100 μL (0.1 mass % solution)

[0135] Standard sample: PMMA CALIBRATION KIT ML-10 manufactured by Agilent Technologies

[0136] (Synthesis Example 1) Synthesis of fluorinated organopolysiloxane (A-1)

[0137] [Chemical formula 8]

[0138]

[0139] Me represents a methyl group (the same applies hereinafter).

[0140] [Chemical formula 9]

[0141]

[0142] [Chemical formula 10]

[0143]

[0144] Ph represents a phenyl group (the same applies hereinafter).

[0145] [Chemical formula 11]

[0146]

[0147] Vi represents a vinyl group (the same applies hereinafter).

[0148] [Chemical formula 12]

[0149]

[0150] 100 parts of cyclotrisiloxane (6) having a fluorine-containing substituent, 4.7 parts of cyclomethylphenyltrisiloxane (7), 0.29 parts of cyclomethylvinyltrisiloxane (8), and 0.23 parts of 1,1,3,3-tetramethyl-1,3-divinyldisiloxane (9) were mixed and stirred, 0.01 parts of trifluoromethanesulfonic acid was added, and the mixture was reacted (equilibrated) at 50°C. Then, 0.2 parts of 28% ammonia water was added, the mixture was stirred at room temperature for 1 hour, the generated salt was filtered with filter paper, and the mixture was stripped at 200°C and 3 mmHg for 30 minutes before GPC measurement. If the area of ​​the component with a molecular weight of 4,000 or less during GPC measurement does not fall within the range of 2 to 20% of the total peak area, the mixture was stripped again under the same conditions and GPC measurement was performed. This operation was repeated until the area of ​​the component having a molecular weight of 4,000 or less in GPC measurement fell within the range of 2 to 20% of the total peak area, thereby obtaining the fluorinated organopolysiloxane (A-1) shown in Table 1. The fluorine content of the fluorinated organopolysiloxane was 42% by mass, the ratio of the total number of phenyl groups to the total number of monovalent substituents bonded to silicon atoms was 3.0%, and the area of ​​the component having a molecular weight of 4,000 or less in the total peak area in GPC measurement was 17%.

[0151] (A-1)

[0152] [Chemical formula 13]

[0153]

[0154] (Synthesis Example 2) Synthesis of fluorinated organopolysiloxane (A-2)

[0155] A fluorine-containing organopolysiloxane (A-2) was synthesized in the same manner as in Synthesis Example 1 except that 100 parts of cyclotrisiloxane (6) having a fluorine-containing substituent, 46.4 parts of cyclomethylphenyltrisiloxane (7), 0.53 parts of cyclomethylvinyltrisiloxane (8), and 0.42 parts of 1,1,3,3-tetramethyl-1,3-divinyldisiloxane (9) were used. The fluorine content of the fluorine-containing organopolysiloxane was 30% by mass, the ratio of the total number of phenyl groups to the total number of monovalent substituents bonded to silicon atoms was 16.2%, and the area of ​​components having a molecular weight of 4,000 or less in the total peak area measured by GPC was 11%.

[0156] (A-2)

[0157] [Chemical formula 14]

[0158]

[0159] (Synthesis Example 3) Synthesis of fluorinated organopolysiloxane (A-3)

[0160] [Chemical formula 15]

[0161]

[0162] [Chemical formula 16]

[0163]

[0164] A fluorine-containing organopolysiloxane (A-3) was synthesized in the same manner as in Synthesis Example 1 except that 100 parts of cyclotrisiloxane (10) having a fluorine-containing substituent, 26.4 parts of cyclomethylphenyltrisiloxane (7), 0.26 parts of cyclomethylvinyltrisiloxane (8), and 0.21 parts of 1,1,3,3-tetramethyl-1,3-divinyldisiloxane (9) were used. The fluorine content of the fluorine-containing organopolysiloxane was 46% by mass, the ratio of the total number of phenyl groups to the total number of monovalent substituents bonded to silicon atoms was 18.6%, and the area of ​​components having a molecular weight of 4,000 or less in the total peak area measured by GPC was 6%.

[0165] (A-3)

[0166] [Chemical formula 17]

[0167]

[0168] (Synthesis Example 4) Synthesis of fluorinated organopolysiloxane (A-4)

[0169] A fluorine-containing organopolysiloxane (A-4) was synthesized in the same manner as in Synthesis Example 1 except that 100 parts of cyclotrisiloxane (10) having a fluorine-containing substituent, 11.9 parts of cyclomethylphenyltrisiloxane (7), 0.18 parts of cyclomethylvinyltrisiloxane (8), and 0.14 parts of 1,1,3,3-tetramethyl-1,3-divinyldisiloxane (9) were used. The fluorine content of the fluorine-containing organopolysiloxane was 52% by mass, the ratio of the total number of phenyl groups to the total number of monovalent substituents bonded to silicon atoms was 12.3%, and the area of ​​components having a molecular weight of 4,000 or less in the total peak area measured by GPC was 9%.

[0170] (A-4)

[0171] [Chemical formula 18]

[0172]

[0173] (Synthesis Example 5) Synthesis of fluorinated organopolysiloxane (A-5)

[0174] [Chemical formula 19]

[0175]

[0176] A fluorine-containing organopolysiloxane (A-5) was synthesized in the same manner as in Synthesis Example 1 except that 100 parts of cyclotrisiloxane (6) having a fluorine-containing substituent, 77.1 parts of cyclomethylphenyltrisiloxane (7), 1.34 parts of cyclomethylvinyltrisiloxane (8), 1.06 parts of 1,1,3,3-tetramethyl-1,3-divinyldisiloxane (9), and 74.8 parts of cyclodimethyltrisiloxane (11) were used. The fluorine content of the fluorine-containing organopolysiloxane was 15% by mass, the ratio of the total number of phenyl groups to the total number of monovalent substituents bonded to silicon atoms was 10.7%, and the area of ​​components having a molecular weight of 4,000 or less in the total peak area measured by GPC was 16%.

[0177] (A-5)

[0178] [Chemical formula 20]

[0179]

[0180] (Synthesis Example 6) Synthesis of fluorinated organopolysiloxane (A-6)

[0181] A fluorine-containing organopolysiloxane (A-6) was synthesized in the same manner as in Synthesis Example 1 except that 100 parts of cyclotrisiloxane (10) having a fluorine-containing substituent, 0.31 parts of cyclomethylvinyltrisiloxane (8), 0.25 parts of 1,1,3,3-tetramethyl-1,3-divinyldisiloxane (9), and 4.7 parts of cyclodimethyltrisiloxane (11) were used. The fluorine content of the fluorine-containing organopolysiloxane was 42% by mass, the ratio of the total number of phenyl groups to the total number of monovalent substituents bonded to silicon atoms was 0.0%, and the area of ​​components having a molecular weight of 4,000 or less in the total peak area measured by GPC was 10%.

[0182] (A-6)

[0183] [Chemical formula 21]

[0184]

[0185] (Synthesis Example 7) Synthesis of fluorinated organopolysiloxane (A-7)

[0186] A fluorinated organopolysiloxane (A-7) was synthesized in the same manner as in Synthesis Example 1 except that 100 parts of cyclotrisiloxane (10) having a fluorinated substituent, 38.3 parts of cyclomethylphenyltrisiloxane (7), 0.33 parts of cyclomethylvinyltrisiloxane (8), and 0.26 parts of 1,1,3,3-tetramethyl-1,3-divinyldisiloxane (9) were used. The fluorine content of the fluorinated organopolysiloxane was 42% by mass, the ratio of the total number of phenyl groups to the total number of monovalent substituents bonded to silicon atoms was 21.6%, and the area of ​​components having a molecular weight of 4,000 or less in the total peak area measured by GPC was 13%.

[0187] (A-7)

[0188] [Chemical formula 22]

[0189]

[0190] (Synthesis Example 8) Synthesis of fluorinated organopolysiloxane (A-8)

[0191] A fluorinated organopolysiloxane (A-8) was synthesized in the same manner as in Synthesis Example 1 except that the above steps were repeated until the area of ​​the component having a molecular weight of 4,000 or less in GPC accounted for less than 2% of the total peak area. The fluorine content of the fluorinated organopolysiloxane was 42% by mass, the ratio of the total number of phenyl groups to the total number of monovalent substituents bonded to silicon atoms was 3.0%, and the area of ​​the component having a molecular weight of 4,000 or less in the total peak area measured by GPC was 1.3%.

[0192] (Synthesis Example 9) Synthesis of fluorinated organopolysiloxane (A-9)

[0193] Except for setting the cleaning conditions to be carried out at 100 °C and 30 mmHg for 30 minutes, the fluorine-containing organopolysiloxane (A-9) was synthesized in the same manner as in Synthesis Example 1. The fluorine content of this fluorine-containing organopolysiloxane was 44.0% by mass, the ratio of the total number of phenyl groups to the total number of monovalent substituents bonded to silicon atoms was 3.0%, and the peak area of the components with a molecular weight of 4,000 or less in the total peak area during GPC measurement was 25%.

[0194] The parameters of the fluorine-containing organopolysiloxanes (A-1) to (A-9) are summarized in Table 1.

[0195] [Table 1]

[0196] Parameters of the fluorine-containing organopolysiloxanes (A-1) to (A-9)

[0197]

[0198] Parameter 1: Fluorine content rate (% by mass)

[0199] Parameter 2: Ratio of the total number of phenyl groups to the total number of monovalent substituents bonded to silicon atoms (mol%)

[0200] Parameter 3: Ratio of the area of the components with a molecular weight of 4,000 or less to the total peak area in the molecular weight distribution measurement based on GPC analysis (%)

[0201] (Synthesis Example 10) Synthesis of fluorine-containing organohydrogenpolysiloxane (B-1)

[0202] [Chemical formula 23]

[0203]

[0204] [Chemical formula 24]

[0205]

[0206] 100 parts of organohydrogenpolysiloxane (12) and 194 parts of allyl ether form of perfluoropolyether were mixed and stirred, and an addition reaction was carried out using a platinum vinylsiloxane complex CAT-PL-50T (manufactured by Shin-Etsu Chemical Co., Ltd.) as a catalyst. After activated carbon treatment, filtration, and cleaning, the fluorine-containing organohydrogenpolysiloxane (B-1) represented by the following molecular formula was obtained.

[0207] [Chemical formula 25]

[0208]

[0209] (Examples 1 to 3 and Comparative Examples 1 to 6)

[0210] The molar ratio of hydrogen atoms bonded to silicon atoms in the component (B) to the vinyl groups in the component (A) (Si—H groups / Si—CH=CH 2 The organohydrogenpolysiloxane (B-1) was mixed with the organopolysiloxanes containing alkenyl substituents and fluorine substituents represented by (A-1) to (A-9) above, respectively, so that the molar ratio of ...

[0211] [Table 2]

[0212]

[0213] [Table 3]

[0214]

[0215] The solubility in non-fluorinated solvents, coating properties on film substrates, adhesion, peel strength, and residual adhesive strength of the silicone composition solution obtained in the above manner were measured by the following methods.

[0216] (a) Solubility

[0217] 50 g of the samples (solid content concentration 5%) prepared in the above Examples and Comparative Examples were placed in a 100 mL glass bottle with a transparent cap, shaken for 5 minutes using a shaker, and the appearance of the samples was observed.

[0218] ○: Transparent △: Slightly turbid ×: White turbidity or separation

[0219] (b) Coating properties on film substrates

[0220] A bar coater was used so that the coating amount was 0.3 g / m 2 The samples prepared in the above-mentioned examples and comparative examples (dilution solvent: isooctane / isobutyl acetate = 50:50) were coated on a PET film having a thickness of 50 μm. The appearance of the coated film was observed.

[0221] ○: No liquid shrinkage or uneven coating

[0222] △: There is a little liquid shrinkage or uneven coating

[0223] ×: Liquid shrinkage or uneven coating

[0224] (c) Adhesion to substrate

[0225] The film obtained in (b) was heat-cured in a hot air dryer at 150°C for 60 seconds to form a release layer. The film with the release layer was stored at 60°C and 90 RH% for 3 days, and then the release layer was rubbed 10 times with fingers to visually observe whether it fell off.

[0226] ○: Not falling off

[0227] △: The color of the film has changed but has not fallen off

[0228] ×: There is falling off

[0229] (d) Peeling force by transfer method

[0230] 50 parts by mass of toluene were added to 100 parts by mass of an addition-curing silicone pressure-sensitive adhesive (Shin-Etsu Chemical Co., Ltd.: KR-3701), and a complex of chloroplatinic acid and vinyl siloxane was added so that the amount of platinum was 30 ppm. The obtained composition was applied to the release layer of the film (width: 25 mm) obtained in (c) using an applicator so that the thickness after curing was 50 μm. The film was then heated at 150°C for 1 minute to cure, and a PET film (width: 25 mm) with a thickness of 50 μm was attached from above the pressure-sensitive adhesive layer to obtain a pressure-sensitive adhesive tape having a release layer. At 20 g / cm 2 The obtained pressure-sensitive adhesive tape with a release layer was laminated at 25°C and 70°C for 20 hours under a load to age. The PET film on the pressure-sensitive adhesive layer side of the pressure-sensitive adhesive tape with a release layer was peeled off at an angle of 180 degrees at a peeling speed of 0.3 m / min using a tensile tester, and the force required for peeling (N / 25 mm) was measured.

[0231] ○: less than 0.3 N / 25 mm

[0232] △: 0.3 N / 25 mm or more and less than 1.0 N / 25 mm

[0233] ×: 1.0 N / 25 mm or more

[0234] (e) Residual Adhesion

[0235] A pressure-sensitive adhesive tape having a release layer was prepared in the same manner as in (d) and 2The pressure-sensitive adhesive tape was laminated at 25°C for 20 hours under a load of 1000 g to allow it to mature. After aging, the PET film on the pressure-sensitive adhesive layer side of the pressure-sensitive adhesive tape with a release layer was peeled off and pasted on a SUS (stainless steel) plate. The pressure-sensitive adhesive tape was peeled off at an angle of 180 degrees at a peeling speed of 0.3 m / min using a tensile testing machine, and the force required for peeling (N / 25 mm) was measured.

[0236] ○: 9 N / 25 mm or more

[0237] △: Less than 9 N / 25 mm and 5 N / 25 mm or more

[0238] ×: less than 5 N / 25 mm

[0239] [Table 4]

[0240]

[0241] For Comparative Example 1, since the fluorine-containing organopolysiloxane (A-4) is not dissolved in the non-fluorine solvent, the coating property, adhesion, peeling force, and residual adhesive force cannot be measured. For Comparative Example 2, since the fluorine content of the fluorine-containing organopolysiloxane (A-5) is less than 25% by mass, the peeling force becomes heavier and the residual adhesive force also decreases. For Comparative Example 3, since the phenyl content of the fluorine-containing organopolysiloxane (A-6) is less than 0.1 mol%, the adhesion deteriorates and the peeling force increases. For Comparative Example 4, since the phenyl content of the fluorine-containing organopolysiloxane (A-7) is greater than 20 mol%, the adhesion decreases. For Comparative Example 5, since the area of ​​the components with a molecular weight of less than 4,000 in the GPC measurement of the fluorine-containing organopolysiloxane (A-8) is less than 2% relative to the total peak area, the solubility and coating property are poor, and the peeling force and residual adhesive force cannot be measured. In Comparative Example 6, since the ratio of the area of ​​the component having a molecular weight of 4,000 or less to the total peak area in the GPC measurement of the fluorinated organopolysiloxane (A-9) was greater than 20%, the adhesion was poor and the residual adhesive force decreased.

[0242] Compared with these comparative examples, the results of each sample of Examples 1 to 3 are excellent in solubility in non-fluorinated solvents, coating properties on substrates, and adhesion, and are easy to peel off from silicone pressure-sensitive adhesives, and the residual adhesive force is also high. The results of the addition-curable release silicone composition for silicone pressure-sensitive adhesives of the present invention are that as a release agent for silicone pressure-sensitive adhesives, the fluorine content of component (A) as the base polymer, the content of aryl groups and aralkyl groups, and the amount of components with a molecular weight of 4,000 or less are extremely important.

[0243] This specification contains the following protocols.

[0244] [1] An addition-curable release silicone composition for a silicone pressure-sensitive adhesive, comprising:

[0245] (A) a fluorine-containing organopolysiloxane having in one molecule at least two alkenyl groups bonded to silicon atoms and at least one fluorine-containing substituent bonded to silicon atoms, and at least one aryl group and / or aralkyl group bonded to silicon atoms, wherein the fluorine content is 25 to 50% by mass, and the ratio of the total number of the aryl groups and the aralkyl groups to the total number of monovalent substituents bonded to silicon atoms is 0.1 to 20 mol %, and in a molecular weight distribution measurement obtained by gel permeation chromatography, the area of ​​components having a molecular weight of 4,000 or less is 2 to 20% of the total peak area, wherein the fluorine-containing organopolysiloxane (A) is 100 parts by mass;

[0246] (B) an organohydrogenpolysiloxane having at least three hydrogen atoms (SiH groups) bonded to silicon atoms in one molecule, wherein the molar ratio of the hydrogen atoms (SiH groups) bonded to silicon atoms in the component (B) to the alkenyl groups in the component (A) is 0.1 to 15;

[0247] (C) a platinum group metal catalyst, the amount of which is 0.5 to 5,000 ppm based on the mass of the platinum group metal relative to the component (A); and

[0248] (D) a non-fluorinated solvent in an amount of 100 to 20,000 parts by mass.

[0249] [2] The addition-curable release silicone composition for silicone pressure-sensitive adhesives according to [1], wherein the molar ratio of hydrogen atoms bonded to silicon atoms (SiH groups) in the component (B) to the alkenyl groups in the component (A) is 0.5 to 5.

[0250] [3] The addition-curable release silicone composition for silicone pressure-sensitive adhesives according to [1] or [2], wherein the ratio of the total number of aryl groups and arylalkyl groups to the total number of monovalent substituents bonded to silicon atoms in the component (B) is 0 to 50 mol %.

[0251] [4] The addition-curable release silicone composition for silicone pressure-sensitive adhesives according to any one of [1] to [3], wherein the component (D) is a non-fluorinated solvent having an SP value of 10.0 or less.

[0252] [5] The addition-curable release silicone composition for silicone pressure-sensitive adhesives as described in any one of [1] to [4], wherein the component (D) is at least one selected from hydrocarbon solvents, ketone solvents, ether solvents and ester solvents.

[0253] [6] A release film having a cured product layer of the addition-curable release silicone composition for silicone pressure-sensitive adhesives according to any one of [1] to [5] formed on at least one outer surface of a film substrate.

[0254] [7] A release paper having a cured product layer of the addition-curable release silicone composition for silicone pressure-sensitive adhesives according to any one of [1] to [5] formed on at least one outer surface of a paper substrate.

[0255] In addition, when the present invention is further expressed from other perspectives and from different perspectives, it is as follows <1> ~ <16> .

[0256] <1> An addition-curable release silicone composition for silicone pressure-sensitive adhesives, comprising:

[0257] (A) a fluorine-containing organopolysiloxane having in one molecule at least one alkenyl group bonded to a silicon atom and at least one fluorine-containing substituent bonded to a silicon atom, and at least one aryl group and / or aralkyl group bonded to a silicon atom, and having a fluorine content of 25 to 50% by mass;

[0258] (B) an organohydrogenpolysiloxane having at least one hydrogen atom (SiH group) bonded to a silicon atom in one molecule;

[0259] (C) platinum group metal catalysts; and

[0260] (D) Non-fluorinated solvents.

[0261] <2> An addition-curable release silicone composition for silicone pressure-sensitive adhesives, comprising:

[0262] (A) a fluorinated organopolysiloxane having in one molecule at least one alkenyl group bonded to a silicon atom and at least one fluorinated substituent bonded to a silicon atom, and at least one aryl group and / or aralkyl group bonded to a silicon atom, wherein the ratio of the total number of the aryl groups and the aralkyl groups to the total number of the monovalent substituents bonded to the silicon atom is 0.1 to 20 mol%;

[0263] (B) an organohydrogenpolysiloxane having at least one hydrogen atom (SiH group) bonded to a silicon atom in one molecule;

[0264] (C) platinum group metal catalysts; and

[0265] (D) Non-fluorinated solvents.

[0266] <3> An addition-curable release silicone composition for silicone pressure-sensitive adhesives, comprising:

[0267] (A) a fluorinated organopolysiloxane having in one molecule at least one alkenyl group bonded to a silicon atom and at least one fluorinated substituent bonded to a silicon atom, and at least one aryl group and / or aralkyl group bonded to a silicon atom, wherein in a molecular weight distribution measurement by gel permeation chromatography, the area of ​​a component having a molecular weight of 4,000 or less is 2 to 20% of the total peak area;

[0268] (B) an organohydrogenpolysiloxane having at least one hydrogen atom (SiH group) bonded to a silicon atom in one molecule;

[0269] (C) platinum group metal catalysts; and

[0270] (D) Non-fluorinated solvents.

[0271] <4> like <1> ~ <3> The addition-curable releasable silicone composition for silicone pressure-sensitive adhesives described in any one of the preceding claims, wherein the molar ratio of hydrogen atoms (SiH groups) bonded to silicon atoms in the component (B) to alkenyl groups in the component (A) is 0.5 to 5.

[0272] <5> like <1> ~ <3> The addition-curable releasable silicone composition for silicone pressure-sensitive adhesives according to any one of the preceding claims, wherein in the component (B), the ratio of the total number of aryl groups and aralkyl groups to the total number of monovalent substituents bonded to silicon atoms is 0 to 50 mol %.

[0273] <6> like <1> ~ <3> In any one of the above-described addition-curable releasable silicone compositions for silicone pressure-sensitive adhesives, the component (D) is a non-fluorine-based solvent having an SP value of 10.0 or less.

[0274] <7> like <4> In the addition-curable releasable silicone composition for silicone pressure-sensitive adhesive, the component (D) is a non-fluorine-based solvent having an SP value of 10.0 or less.

[0275] <8> like <5> In the addition-curable releasable silicone composition for silicone pressure-sensitive adhesive, the component (D) is a non-fluorine-based solvent having an SP value of 10.0 or less.

[0276] <9> like <1> ~ <3> In any one of the above addition-curable releasable silicone compositions for silicone pressure-sensitive adhesives, the component (D) is at least one selected from hydrocarbon solvents, ketone solvents, ether solvents and ester solvents.

[0277] <10> like <4> In the addition-curable releasable silicone composition for silicone pressure-sensitive adhesive, the component (D) is at least one selected from hydrocarbon solvents, ketone solvents, ether solvents and ester solvents.

[0278] <11> like <5> In the addition-curable releasable silicone composition for silicone pressure-sensitive adhesive, the component (D) is at least one selected from hydrocarbon solvents, ketone solvents, ether solvents and ester solvents.

[0279] <12> like <6> In the addition-curable releasable silicone composition for silicone pressure-sensitive adhesive, the component (D) is at least one selected from hydrocarbon solvents, ketone solvents, ether solvents and ester solvents.

[0280] <13> like <7> In the addition-curable releasable silicone composition for silicone pressure-sensitive adhesive, the component (D) is at least one selected from hydrocarbon solvents, ketone solvents, ether solvents and ester solvents.

[0281] <14> like <8> In the addition-curable releasable silicone composition for silicone pressure-sensitive adhesive, the component (D) is at least one selected from hydrocarbon solvents, ketone solvents, ether solvents and ester solvents.

[0282] <15> A release film having a film substrate formed on at least one outer surface thereof <1> ~ <14> A cured product layer of the addition-curable release silicone composition for silicone pressure-sensitive adhesives as described in any one of the preceding claims.

[0283] <16> A release paper having a plurality of layers formed on at least one outer surface of a paper substrate. <1> ~ <14> A cured product layer of the addition-curable release silicone composition for silicone pressure-sensitive adhesives as described in any one of the preceding claims.

[0284] Above <1> ~ <16> Sometimes the balance of various properties may change by changing the blending ratio of each component. In this case, several properties may become unstable or deteriorate, but since the desired properties vary depending on the application, it can be used in practice according to the application.

[0285] The present invention is not limited to the above-mentioned embodiments. The above-mentioned embodiments are merely examples, and all solutions having substantially the same configuration and exerting the same effects as the technical concept described in the claims of the present invention are included in the technical scope of the present invention.

[0286] Industrial Applicability

[0287] The addition-curable release silicone composition for silicone pressure-sensitive adhesives of the present invention can be suitably used as a release agent because it has both high handling properties and good release performance. A sheet-like substrate having a cured film composed of the silicone composition is useful for pressure-sensitive adhesive tapes, pressure-sensitive adhesive labels, engineering paper, and the like.

Claims

1. An addition-curable release silicone composition for silicone pressure-sensitive adhesives, comprising: (A) a fluorine-containing organopolysiloxane having in one molecule at least two alkenyl groups bonded to silicon atoms and at least one fluorine-containing substituent bonded to silicon atoms, and at least one aryl group and / or aralkyl group bonded to silicon atoms, wherein the fluorine content is 25 to 50% by mass, and the ratio of the total number of the aryl groups and the aralkyl groups to the total number of monovalent substituents bonded to silicon atoms is 0.1 to 20 mol %, and in a molecular weight distribution measurement by gel permeation chromatography, the area of ​​components having a molecular weight of 4,000 or less is 2 to 20% of the total peak area, wherein the fluorine-containing organopolysiloxane (A) is 100 parts by mass; (B) an organohydrogenpolysiloxane having at least three hydrogen atoms (SiH groups) bonded to silicon atoms in one molecule, wherein the molar ratio of the hydrogen atoms (SiH groups) bonded to silicon atoms in the component (B) to the alkenyl groups in the component (A) is 0.1 to 15; (C) a platinum group metal catalyst, in an amount of 0.5 to 5,000 ppm based on the mass of the platinum group metal relative to the component (A); and (D) a non-fluorinated solvent in an amount of 100 to 20,000 parts by mass.

2. The addition-curable release silicone composition for silicone pressure-sensitive adhesive according to claim 1, in, The molar ratio of hydrogen atoms bonded to silicon atoms (SiH groups) in the component (B) to alkenyl groups in the component (A) is 0.5 to 5.

3. The addition-curable release silicone composition for silicone pressure-sensitive adhesive according to claim 1, in, In the component (B), the ratio of the total number of aryl groups and aralkyl groups to the total number of monovalent substituents bonded to silicon atoms is 0 to 50 mol %.

4. The addition-curable release silicone composition for silicone pressure-sensitive adhesive according to claim 1, in, The component (D) is a non-fluorinated solvent having an SP value of 10.0 or less.

5. The addition-curable releasable silicone composition for silicone pressure-sensitive adhesive according to claim 2, in, The component (D) is a non-fluorinated solvent having an SP value of 10.0 or less.

6. The addition-curable releasable silicone composition for silicone pressure-sensitive adhesive according to claim 3, in, The component (D) is a non-fluorinated solvent having an SP value of 10.0 or less.

7. The addition-curable releasable silicone composition for silicone pressure-sensitive adhesive according to claim 1, in, The component (D) is at least one selected from hydrocarbon solvents, ketone solvents, ether solvents and ester solvents.

8. The addition-curable releasable silicone composition for silicone pressure-sensitive adhesive according to claim 2, in, The component (D) is at least one selected from hydrocarbon solvents, ketone solvents, ether solvents and ester solvents.

9. The addition-curable releasable silicone composition for silicone pressure-sensitive adhesive according to claim 3, in, The component (D) is at least one selected from hydrocarbon solvents, ketone solvents, ether solvents and ester solvents.

10. The addition-curable releasable silicone composition for silicone pressure-sensitive adhesive according to claim 4, in, The component (D) is at least one selected from hydrocarbon solvents, ketone solvents, ether solvents and ester solvents.

11. The addition-curable releasable silicone composition for silicone pressure-sensitive adhesive according to claim 5, in, The component (D) is at least one selected from hydrocarbon solvents, ketone solvents, ether solvents and ester solvents.

12. The addition-curable releasable silicone composition for silicone pressure-sensitive adhesive according to claim 6, in, The component (D) is at least one selected from hydrocarbon solvents, ketone solvents, ether solvents and ester solvents. 13 . A release film comprising a film substrate having a cured product layer formed on at least one outer surface of the addition-curable release silicone composition for a silicone pressure-sensitive adhesive according to claim 1 . 14 . A release paper comprising a cured product layer of the addition-curable release silicone composition for silicone pressure-sensitive adhesives according to claim 1 formed on at least one outer surface of a paper substrate.

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