WO2021192100A1

WO2021192100A1 - Silicone composition for release sheets, and release sheet

Info

Publication number: WO2021192100A1
Application number: PCT/JP2020/013381
Authority: WO
Inventors: 山本　謙児; イルグォンチャン
Original assignee: 信越化学工業株式会社
Priority date: 2020-03-25
Filing date: 2020-03-25
Publication date: 2021-09-30
Also published as: CN115298282B; JP7333866B2; KR102698825B1; KR20220157399A; JPWO2021192100A1; TW202136441A; CN115298282A

Abstract

The present invention is a silicone composition for release sheets that comprises: (A) organopolysiloxane in one molecule of which there are at least two alkenyl groups and in which the alkenyl group content is 0.001-0.2 mol/100 g; (B1) organopolysiloxane in one molecule of which the amount of siloxane units having a glycidyl group or glycidoxy group bonded to a silicon atom via a carbon atom is not less than 10 mol%, which contains 0.002-0.02 mol/100 g of silanol groups, which contains 0.5-2.5 mol/100 g of alkoxy groups, and which has an average polymerization degree of 3-50; (B2) organohydrogensiloxane which has not less than 1.3 mol/100 g of Si-H groups and which has a polymerization degree of 10-100; and (D) a platinum group metal-based catalyst. Thus, provided is a silicone composition for release sheets which has excellent adhesion to base materials, which is capable of maintaining said adhesion even in harsh environments, and which enables formation of a cured film that imparts a small release force.

Description

Silicone composition for release sheet and release sheet

The present invention relates to a silicone composition for a release sheet and a release sheet obtained by using the composition.

Conventionally, a cured film of a silicone composition is formed on the surface of a sheet-like base material such as paper or a plastic film to impart peeling characteristics to an adhesive material.

As a method for forming a cured film of a silicone composition on the surface of a base material, for example, in Patent Document 1, an organopolysiloxane containing an alkenyl group and an organohydrogenpolysiloxane are subjected to an addition reaction using a platinum-based compound as a catalyst. Therefore, a method of forming a peelable film on the surface of a base material has been reported.
Although this type of silicone composition adheres well to a paper substrate, it has poor adhesion to plastic films such as polyester film and polypropylene film, and it has been pointed out that there are inconveniences such as the need for pretreatment of the substrate. It had been.

As a method for improving the adhesion to a base material, a composition of a base polymer having a branched structure containing _{3/2 units of RSiO has been reported in Patent Document 2.} However, this method is not practical because the production cost increases due to the use of a large amount of branched organopolysiloxane containing an alkenyl group.

Patent Document 3 reports the addition of an organopolysiloxane having an epoxy group as a method for improving the adhesion to the substrate by using a small amount of the additive. However, this method only describes the adhesion of the substrate under high temperature and high humidity conditions, and has not been evaluated immediately after curing or stored at room temperature. Further, the influence of the peeling property due to the addition of the organopolysiloxane having an epoxy group is not described.

In Patent Document 4, the adhesion to the substrate is improved by adding a reaction product of a liquid polyorganicsiloxane containing an alkenyl group and a silanol group and a hydrolyzable silane containing an epoxide group. However, also in this method, the influence of the peeling property due to the addition has not been investigated.

In Patent Document 5, a small molecule siloxane containing an alkenyl group is added, irradiated with ultraviolet rays, and then the coating film is cured by heating to improve the adhesion to the substrate without affecting the peeling characteristics. However, this method requires a UV irradiation device together with a heating dryer.

Recently, as the peeling sheet performance, it is required to have a peeling force even smaller than that of the conventional product and high durability capable of maintaining good substrate adhesion even in a harsh environment such as high temperature and high humidity in the peeling sheet molding process. Is becoming. However, existing compositions for release sheets tend to have inferior substrate adhesion as they have a smaller release force, and there is almost no composition that can satisfy the requirements for long-term adhesion in a harsher environment. .. It is considered that the cause is that many of the materials effective for light peeling, for example, the materials used as various transition components, work to reduce the adhesion to the base material, and both the light peeling property and the excellent base material adhesion are compatible. Is difficult in reality.

As described above, with the conventional technology, there is no suitable method capable of achieving both light peelability and excellent substrate adhesion of the silicone composition.

JP-A-47-32072 Japanese Patent No. 2965231 Japanese Unexamined Patent Publication No. 2011-132532 Japanese Patent No. 5507246 Japanese Patent No. 5626097

The present invention has been made in view of the above circumstances, and since the adhesiveness to the substrate is excellent and the peeling force is hardly increased by improving the adhesiveness, a cured film (peeling film) that gives a small peeling force is provided. It is an object of the present invention to provide a silicone composition for a release sheet which can be formed and whose substrate adhesion of the film can be maintained for a long period of time not only at room temperature but also in a harsh environment such as high temperature and high humidity.

Furthermore, it is an object of the present invention to provide a release sheet obtained from the composition of the present invention.

The present invention has been made to solve the above problems, and is an addition-curing type silicone composition for a release sheet.
(A) It has at least two alkenyl groups in one molecule, has an alkenyl group content of 0.001 to 0.2 mol / 100 g, and has a 30 mass% toluene dilution viscosity at 25 ° C. of 0.01 to 70 Pa. Organopolysiloxane: 100 parts by mass;
(B) Component containing the following (B1) compound and (B2) compound (B1) 10 mol% or more of a siloxane unit having a glycidyl group and / or a glycidoxy group bonded to a silicon atom via a carbon atom in one molecule. Organopolysiloxane containing 0.002 to 0.02 mol / 100 g of silanol groups, 0.5 to 2.5 mol / 100 g of alkoxy groups, and an average degree of polymerization of 3 to 50: 0.1 ~ 20 parts by mass;
(B2) Organohydrogensiloxane having 1.3 mol / 100 g or more of Si—H groups and a degree of polymerization of 10 to 100: parts by mass corresponding to 0.02 to 1 times the mass part of the compound (B1). ;
(D) Platinum group metal catalyst: catalyst amount;
(E) Provided is a silicone composition for an addition-curable release sheet, which comprises an organic solvent: 0 to 20,000 parts by mass.

The silicone composition for a release sheet of the present invention contains the above-mentioned components (A), (B) and (D) in a predetermined amount to improve adhesion to a base material, particularly a plastic film base material such as a polyester film. An excellent cured film (release film) can be formed. Further, the cured film obtained from the silicone composition for a release sheet of the present invention can exhibit a small peeling force, and can have good substrate adhesion while exhibiting such a small peeling force, and is at room temperature. Not only that, good substrate adhesion can be maintained for a long period of time even when placed under severe conditions of high temperature and high humidity.

The silicone composition for a release sheet of the present invention further comprises (C) at least two hydrogen atoms bonded to silicon atoms in one molecule, which is different from the compound (B2) above: (B2). ) The total number of moles of the compound and the hydrogen atom bonded to the silicon atom of the component (C) is preferably 0.5 to 10 times the number of moles of the alkenyl group in the composition.

By including such a component (C), better curability can be obtained.

The compound (B1) is an organoalkoxysilane represented by the following general formula (1-1) and an organoalkoxy represented by the following general formulas (1-2), (1-3) and (1-4). It is a partially hydrolyzed condensate with at least one of the silanes, and is preferably an organopolysiloxane having a linear, branched siloxane or cyclic siloxane structure, or a mixture thereof.

(In the formula, R1 is a hydrocarbon group or a hydrogen atom which may contain an unsubstituted or substituted oxygen atom having 1 to 10 carbon atoms which does not have an aliphatic unsaturated bond and may be the same or different. R12 is an unsaturated or substituted hydrocarbon group having 1 to 20 carbon atoms, and n is an integer of 3 to 10).

By including such a (B1) compound, the strength of the cured product can be improved and a higher adhesion improving effect can be exhibited.

The compound (B2) is preferably an organohydrogensiloxane represented by the following general formula (2-1) or (2-2), or a mixture thereof.
(R12) ₃ Si-{(R12) HSiO} _m- Si (R12) ₃ ... (2-1)
(R12) ₂ HSi-{(R12) HSiO} _m- SiH (R12) ₂ ... (2-2)
(In the formula, R12 is an unsubstituted or substituted hydrocarbon group having 1 to 20 carbon atoms, which may be the same or different, and m is an integer of 2 to 100).

By including such a (B2) compound in combination with the (B1) compound, the strength of the cured product can be improved and a higher adhesion improving effect can be exhibited. Since it is difficult to obtain a sufficient adhesiveness improving effect even if the compound (B2) is used alone, the strength of the adhesiveness improving layer formed by the compound at the interface between the silicone cured film and the base material is increased. It is presumed that this is due to the function of strengthening the bond between the adhesion improving layer and the silicone cured film.

The silicone composition for a release sheet of the present invention further contains 0.1 to 10 parts by mass of the component (B3) as the component (B), and the component (B3) has at least two alkenyl groups in one molecule. However, a compound having an alkenyl group content equivalent to 5 to 500 times the alkenyl group content of the component (A), having no epoxy group, and having a viscosity at 25 ° C. of less than 0.5 Pa · s. Yes, the number of moles of hydrogen atom bonded to the silicon atom in the composition corresponds to 0.5 to 10 times the total number of moles of alkenyl groups of the component (A) and the component (B3). Is preferable.

By including such a component (B3), the curability of the composition can be further enhanced, and the adhesion of the obtained cured film to the substrate immediately after curing can be enhanced while maintaining the light peeling effect. can. Although the mechanism by which the effect is exhibited is not clear, the component (B3), which has a higher alkenyl group content and a lower viscosity than the component (A), has less restrictions on molecular movement in the composition and has a SiH group. Since the reactivity of the above is excellent, the curability is improved and the remaining SiH groups are reduced, so that a light peeling effect can also be obtained. Further, as the cross-linking reaction proceeds, the cross-linking density increases, so that it is presumed that the adhesion to the base material immediately after curing is also improved.

The silicone composition for a release sheet of the present invention further contains the following (F1) component and / or the following (F2) component as the release force control component (F) from 0.1 to 100 parts by mass of the (A) component. It is preferable to contain 20 parts by mass.
(F1) (a) Organopolysiloxane compound having an acrylic group and / or a methacryl group represented by the following general formula (3), and (b) radical polymerizable having one radically polymerizable group in one molecule. A peeling force control component containing an acrylic-silicone graft copolymer having a weight average molecular weight of 1,000 to 100,000, which is obtained by radical polymerization of a monomer;

[In the formula, R ² is a hydrogen atom or a methyl group, X is a group selected from an oxygen atom, an NH group and a sulfur atom, and Y is a divalent oxygen atom having 1 to 12 carbon atoms. A hydrocarbon group, R ³ may be the same or different, an unsubstituted or substituted monovalent hydrocarbon group having 1 to 20 carbon atoms, a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 10 carbon atoms, or the following. General formula (4)

(In the formula, R ⁴ is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 20 carbon atoms, a hydrogen atom, a hydroxyl group, or an alkoxy group having 1 to 10 carbon atoms, which may be the same or different. Is an integer from 0 to 300.)
It is a substituent represented by. f is an integer from 0 to 1,000. ]
(F2) Linear phenylmethylpolysiloxane.

By including such a component (F), the peeling force can be adjusted while maintaining the excellent adhesion to the substrate. Further, it is possible to provide an excellent peeling film having a high residual adhesive ratio of the peeled adhesive sheet.

The present invention also provides a release sheet obtained by applying the silicone composition for a release sheet of the present invention to a paper substrate or a film substrate and curing the composition.

Since the release sheet of the present invention is obtained by applying the silicone composition for a release sheet of the present invention to a substrate and curing it, the cured film obtained by curing exhibits a small release force. In addition, good substrate adhesion can be exhibited, and this good substrate adhesion can be maintained for a long period of time not only at room temperature but also under severe conditions of high temperature and high humidity.

According to the silicone composition for a release sheet of the present invention, a non-adhesive cured film having excellent adhesion to a substrate can be obtained, and the non-adhesiveness of the cured film before and after the improvement of adhesiveness is good with almost no change. Excellent peeling characteristics can also be obtained. Although the conventional adhesiveness improving method cannot avoid the influence on the peeling property, the peeling sheet on which the cured film of the silicone composition for the peeling sheet of the present invention is formed has almost the influence on the peeling property. It is possible to improve the adhesion with the base material. Further, the cured film obtained by the silicone composition for a release sheet of the present invention can maintain good substrate adhesion for a long period of time even when placed under severe conditions of high temperature and high humidity.

Hereinafter, the present invention will be described in detail, but the present invention is not limited thereto.
In the present invention, the release sheet may be, for example, a release paper containing a paper base material, or a release film containing a film made of plastic or the like. Further, the composition for a release sheet may be, for example, a silicone composition for a release paper or a silicone composition for a release film.

As a result of diligent studies to achieve the above object, the present inventor has at least two alkenyl groups in one molecule, has an alkenyl group content of 0.001 to 0.2 mol / 100 g, and has 25. 30 mass% toluene diluted at ° C. A component (A) of an organopolysiloxane having a viscosity of 0.01 to 70 Pa · s, and a glycidyl group and / or a glycidoxy group bonded to a silicon atom via a carbon atom in one molecule. It contains 10 mol% or more of siloxane units, 0.002 to 0.02 mol / 100 g of silanol groups, 0.5 to 2.5 mol / 100 g of alkoxy groups, and an average degree of polymerization of 3 to 50. (B1) component which is an organopolysiloxane (B1) and a (B2) compound which is an organohydrogensiloxane having a Si—H group of 1.3 mol / 100 g or more and a degree of polymerization of 10 to 100. , (D) A platinum group metal-based catalyst, and (E) an organic solvent are blended in predetermined amounts, respectively, and it has been found that a cured film having excellent adhesion to a base material can be obtained.

Further, in the conventional adhesiveness improving method, sufficient substrate adhesion could not be obtained with a composition having a small peeling force, but in the composition of the present invention, excellent substrate adhesion is simultaneously realized with a small peeling force. It has also been found that the excellent substrate adhesion can be maintained for a long period of time, and the present invention has been made.

First, in Japanese Patent Application Laid-Open No. 2017-25135, the desired effect was achieved by a composition combining a highly alkenyl group-containing siloxane and an epoxy group-containing siloxane, but in the present invention, a cheaper material is used. We have found a composition that enhances its effect by using it, and have reached the present application.

[Silicone composition for release sheet]
The silicone composition for an addition-curable release sheet of the present invention is
(A) It has at least two alkenyl groups in one molecule, has an alkenyl group content of 0.001 to 0.2 mol / 100 g, and has a 30 mass% toluene dilution viscosity at 25 ° C. of 0.01 to 70 Pa. Organopolysiloxane: 100 parts by mass;
(B) Component containing the following (B1) compound and (B2) compound (B1) 10 mol% or more of a siloxane unit having a glycidyl group and / or a glycidoxy group bonded to a silicon atom via a carbon atom in one molecule. Organopolysiloxane containing 0.002 to 0.02 mol / 100 g of silanol groups, 0.5 to 2.5 mol / 100 g of alkoxy groups, and an average degree of polymerization of 3 to 50: 0.1 ~ 20 parts by mass;
(B2) Organohydrogensiloxane having 1.3 mol / 100 g or more of Si—H groups and a degree of polymerization of 10 to 100: parts by mass corresponding to 0.02 to 1 times the mass part of the compound (B1). ;
(D) Platinum group metal catalyst: catalyst amount;
(E) Organic solvent: It contains 0 to 20,000 parts by mass.

In the silicone composition for a release sheet of the present invention, the organic solvent (E) is an optional component because the blending amount may be 0 parts by mass with respect to 100 parts by mass of the component (A). Further, the silicone composition for a release sheet of the present invention may contain other optional components in addition to the components (A), (B) and (D). Specific examples of the optional component will be described later.

Hereinafter, each component of the silicone composition for a release sheet of the present invention will be described in order.

[Component (A): Organopolysiloxane having an alkenyl group]
The component (A) used in the present invention has at least two alkenyl groups in one molecule, has an alkenyl group content of 0.001 to 0.2 mol / 100 g, and is diluted with 30% by mass of toluene at 25 ° C. It is an organopolysiloxane having a viscosity of 0.01 to 70 Pa · s, and is preferably represented by the following general formula (5).

In the above formula (5), R ⁵ may be the same or different, unsubstituted or substituted monovalent hydrocarbon group having 1 to 20 carbon atoms free of aliphatic unsaturation, or an oxygen atom interposed is also an alkenyl group having 2 to 12 carbon atoms and at least two R ⁵ is an alkenyl group.

As the monovalent hydrocarbon group having 1 to 20 carbon atoms which does not have the aliphatic unsaturated bond, specifically, an alkyl having 1 to 6 carbon atoms such as a methyl group, an ethyl group, a propyl group and a butyl group is preferable. A cycloalkyl group having 5 to 8 carbon atoms, a phenyl group, a trill group or the like, preferably an aryl group having 6 to 10 carbon atoms, a benzyl group or the like, preferably an aralkyl group having 7 to 10 carbon atoms. , And some or all of the hydrogen atoms bonded to the carbon atoms of these groups are substituted with hydroxy groups, cyano groups, halogen atoms, etc., hydroxypropyl groups, cyanoethyl groups, 3-chloropropyl groups, 3,3. , A monovalent hydrocarbon group having 1 to 10 carbon atoms selected from 3-trifluoropropyl groups and the like can be mentioned, but from the viewpoint of releasability, it has 1 to 20 carbon atoms and does not have an aliphatic unsaturated bond. The monohydric hydrocarbon group is preferably an alkyl group or an aryl group, and more preferably a methyl group, an ethyl group, a propyl group or a phenyl group.

The alkenyl group having 2 to 12 carbon atoms which may intervene an oxygen atom _{is preferably a group represented by − (CH 2} ) _x −CH = CH ₂ (x is an integer of 0 or 1 to 10). Specific examples thereof include a vinyl group, a propenyl group, a butenyl group, a hexenyl group, an octenyl group and a decenyl group. Further, the methylene chain may contain an ether bond, and examples thereof include-(CH ₂ ) _2- O-CH ₂ -CH = CH ₂ , -(CH ₂ ) _3- O-CH ₂ -CH = CH _2. Be done. Of these, a vinyl group is preferable.

The number of alkenyl groups in one molecule of the organopolysiloxane of the component (A) is two or more. That is, the organopolysiloxane of the component (A) has at least two alkenyl groups in one molecule. If the number of alkenyl groups is less than 2, there is a high possibility that uncrosslinked molecules will remain even after curing, and the curability will decrease, which is not desirable. The organopolysiloxane of the component (A) can have, for example, 2000 or less alkenyl groups in one molecule. The alkenyl group content per 100 g of the organopolysiloxane of the component (A) is 0.001 to 0.2 mol, more preferably 0.002 to 0.15 mol. If this content is less than 0.001 mol, the curability may decrease, and if it exceeds 0.2 mol, heavy peeling may occur.

The viscosity of the component (A) at 25 ° C. is 0.01 to 70 Pa · s at a 30 mass% toluene dilution viscosity, and is particularly preferably 0.01 to 60 Pa · s at a 30 mass% toluene dilution viscosity. , 30 mass% toluene dilution viscosity is more preferably 0.01 to 50 Pa · s. If it is less than 0.01 Pa · s, the coatability of the composition is not sufficient, and if it exceeds 70 Pa · s, the workability is lowered. The viscosity can be measured with a rotational viscometer (the same applies hereinafter).

H, i, j, and k in the above formula (5) are selected from positive numbers in the above range of viscosity, and in particular, h is 2 or more, preferably an integer of 2 to 300, and i is 100 or more. , Preferably an integer of 148 to 19,998, more preferably 198 to 14,700, j is an integer of 0 or more, preferably 0 to 100, and k is an integer of 0 or more, preferably 0 to 100. Yes, 150 ≦ h + i + j + k ≦ 20,000, preferably 200 ≦ h + i + j + k ≦ 15,000.

Specific examples of the component (A) include, but are not limited to, the following. In addition, Me, Vi and Ph in the following formula represent a methyl group, a vinyl group and a phenyl group, respectively.

[(B) component]
The component (B) used in the present invention is an adhesion improving component, and is a component containing the following (B1) compound and (B2) compound.

(B1) Compound The (B1) compound is a compound having an effect of improving adhesion by blending with the composition of the present invention, and has a glycidyl group bonded to a silicon atom via a carbon atom and a glycidyl group in one molecule. / Or contains 10 mol% or more of a siloxane unit having a glycidyl group, 0.002 to 0.02 mol / 100 g of a silanol group, 0.5 to 2.5 mol / 100 g of an alkoxy group, and average polymerization. It is an organopolysiloxane with a degree of 3 to 50. The compound (B1) is used in an amount of 0.1 to 20 parts by mass with respect to 100 parts by mass of the component (A).

The compound (B1) is a compound having a high effect of maintaining the substrate adhesion of the cured film (release film) obtained by using the composition of the present invention even under heating / humidifying conditions (under a high temperature and high humidity environment). It is a component that is blended with the expectation of an effect of improving adhesion under particularly severe usage conditions. The average degree of polymerization is a polystyrene-equivalent weight average degree of polymerization by gel permeation chromatography (GPC).

Organopolysiloxane, which is a compound (B1), is an organopolysiloxane containing 10 mol% or more of siloxane units having a glycidyl group and / or a glycidoxy group bonded to a silicon atom via a carbon atom in one molecule. If the siloxane unit is less than 10 mol%, the effect of adhering to the substrate cannot be obtained. The upper limit of the content of the siloxane unit is not particularly limited, but can be, for example, 100 mol%.

Organopolysiloxane, which is a compound (B1), contains 0.002 to 0.02 mol / 100 g of silanol groups. If the content of the silanol group is less than 0.002 mol / 100 g, a sufficient adhesion effect to the substrate cannot be obtained. On the other hand, if the content of the silanol group exceeds 0.02 mol / 100 g, the peeling characteristics may be adversely affected. The content of the silanol group is preferably 0.003 to 0.02 mol / 100 g.

Organopolysiloxane, which is a compound (B1), contains 0.5 to 2.5 mol / 100 g of an alkoxy group. If the content of the alkoxy group is less than 0.5 mol / 100 g, a sufficient adhesion effect to the substrate cannot be obtained. On the other hand, if the content of the alkoxy group exceeds 2.5 mol / 100 g, the peeling characteristics may be adversely affected. The content of the alkoxy group is preferably 0.6 to 2.5 mol / 100 g.

Further, the organopolysiloxane which is the (B1) compound has an average degree of polymerization of 3 to 50, preferably 3 to 20. If the average degree of polymerization is less than 3, the adhesion effect to the substrate is not sufficient, and if the average degree of polymerization exceeds 50, the adhesion effect to the substrate is lowered or the workability is lowered.

The organopolysiloxane of the compound (B1) may be linear, branched, or cyclic, or may be a mixture thereof, but is a partially hydrolyzed condensate of organoalkoxysilane. Is preferable. Among the organoalkoxysilanes used as raw materials, the alkoxysilane having a glycidyl group and / or a glycidoxy group bonded to a silicon atom via a carbon atom is preferably a unit trifunctional organoalkoxysilane, and is described below. More preferably, it is an organoalkoxysilane represented by the general formula (1-1).

(In the formula, R1 is a hydrocarbon group or a hydrogen atom which may contain an unsubstituted or substituted oxygen atom having 1 to 10 carbon atoms which does not have an aliphatic unsaturated bond and may be the same or different. n is an integer from 3 to 10.)

Specific examples of the organoalkoxysilane include the following.

The other organoalkoxysilane that is co-hydrolyzed and condensed with the above alkoxysilane is at least one of the organoalkoxysilanes represented by the following general formulas (1-2), (1-3), and (1-4). One or more are preferably used, and more preferably trifunctional and tetrafunctional alkoxysilanes of the following general formulas (1-3) and (1-4) are used. By including such a branched structure or a three-dimensional crosslinked structure in the molecule or by giving the ability to form the cured product in the process of forming the cured product, the strength of the cured product is improved, and the cured product is mainly composed of a linear structure. By appropriately reducing the solubility and dispersibility of the (B1) compound in the silicone cured film layer having excellent releasability, the effect of facilitating the concentration of the (B1) compound near the interface between the base material and the silicone cured film also works. It is considered that this will exert a higher effect of improving adhesion.

(R12) _2- Si (OR1) ₂ ... (1-2)
R12-Si (OR1) ₃ ... (1-3)
Si (OR1) ₄ ... (1-4)
(In the formula, R1 is a hydrocarbon group or hydrogen atom which may contain an unsubstituted or substituted oxygen atom having 1 to 10 carbon atoms which does not have an aliphatic unsaturated bond and may be the same or different. R12 is an unsaturated or substituted hydrocarbon group having 1 to 20 carbon atoms)

A specific organoalkoxysilane that is co-hydrolyzed and condensed with an alkoxysilane having a glycidyl group and / or a glycidoxy group bonded to a silicon atom via a carbon atom (for example, an organoalkoxysilane of the general formula (1-1)). Examples include the following:

In the above formula (1-1), the hydrogen atom on the monovalent organic group having a glycidoxy group may be replaced by a substituent. The substituent here is preferably a substituent other than the epoxycyclohexyl group from the viewpoint of safety and economy. Examples of the epoxycyclohexyl group include a 3,4-epoxycyclohexylmethyl group, a 2- (3,4-epoxycyclohexyl) ethyl group, a 3- (3,4-epoxycyclohexyl) propyl group and the like.

Further, R1 is a hydrocarbon group or a hydrogen atom which may contain an unsubstituted or substituted oxygen atom having 1 to 10 carbon atoms which does not have an aliphatic unsaturated bond. Specifically, the hydrocarbon group as R1 is, for example, an alkyl group such as a methyl group, an ethyl group, a propyl group or a butyl group, a cycloalkyl group such as a cyclohexyl group, an aryl group such as a phenyl group or a trill group, or a benzyl. Examples thereof include an aralkyl group such as a group and a phenethyl group, or a group in which a part or all of the hydrogen atom bonded to the carbon atom of these groups is substituted with a hydroxy group, for example, a hydroxypropyl group. Among these groups, R1 is preferably a hydrogen atom or an alkyl group, and more preferably an alkyl group having 1 to 5 carbon atoms.

The general formula (1-1) to (1-4) represented by organoalkoxysilanes partially hydrolyzed condensation reaction respectively ^T E the following siloxane units formed by, D, T, as Q, (B1) The compound can be shown as an average formula of _{D a} T ^E _b T _c Q _d.

Here, a + b + c + d is 3 to 50, b / (a + b + c + d) is 0.1 to 1, a, c and d are 0 to 35 independently, respectively, and the molecular ends that do not form a siloxane bond with other siloxane units are It is an alkoxy group or a silanol group.

The compound (B1) preferably does not have an alkenyl group in the molecule. By including such a compound (B1), the effect of adhesion to the substrate can be enhanced.

The blending amount of the compound (B1) is in the range of 0.1 to 20 parts by mass, preferably 0.5 to 15 parts by mass with respect to 100 parts by mass of the organopolysiloxane of the component (A). If it is less than 0.1 parts by mass, the adhesion to the substrate cannot be improved, and if it exceeds 20 parts by mass, the peeling characteristics are affected and the strength of the cured film is lowered. On the other hand, if it exceeds 20 parts by mass, it may not be possible to maintain excellent adhesion to the base material for a long period of time in a harsh environment.

Specific examples of the (B1) compound include the following.

As a more preferable example,

And so on.

(B2) Compound The (B2) compound is an organohydrogensiloxane having a Si—H group of 1.3 mol / 100 g or more and a degree of polymerization of 10 to 100, and when used in combination with the (B1) compound, the adhesion thereof is achieved. The improvement effect is further enhanced. If the Si—H group of the compound (B2) is less than 1.3 mol / 100 g, the effect of improving adhesion cannot be obtained. The upper limit of the Si—H group contained in the compound (B2) is not particularly limited, but can be, for example, 1.7 mol / 100 g.

Since it is difficult to obtain a sufficient adhesion improving effect even if the compound (B2) is used alone, the strength of the adhesion improving layer formed by the compound at the interface between the silicone cured film and the base material is increased to improve the adhesion. It is speculated that it may work to strengthen the bond between the layer and the silicone cured film.

The degree of polymerization is 10 to 100, and if it is less than 10, the effect of improving adhesion is low, and if it exceeds 100, the stability is lowered, which is not desirable. The degree of polymerization of the compound (B2) is more preferably 15 to 100.

The preferred structure of the compound (B2) is an organohydrogensiloxane having a linear or branched structure in which the _{main chain is mainly composed of the siloxane unit H (R12) SiO 2/2.} Here, R12 is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 20 carbon atoms, which may be the same or different.

More preferably, it is an organohydrogensiloxane represented by the following general formula (2-1) or (2-2), or a mixture thereof.
(R12) ₃ Si-{(R12) HSiO} _m- Si (R12) ₃ ... (2-1)
(R12) ₂ HSi-{(R12) HSiO} _m- SiH (R12) ₂ ... (2-2)
(In the formula, R12 is an unsubstituted or substituted hydrocarbon group having 1 to 20 carbon atoms, which may be the same or different, and m is an integer of 2 to 100).

The blending amount of the (B2) compound is adjusted according to the blending amount of the (B1) compound used in combination. As a result, the effect of improving adhesion can be obtained. The specific compounding amount is 0.02 to 1 times by mass with respect to the mass part of the compound (B1). If it is less than 0.02 times, the effect of improving adhesion is small, and if it exceeds 1 times, it may affect the peeling characteristics such as heavy peeling. The blending amount of the compound (B2) is preferably 0.03 to 1 times by mass with respect to the mass part of the compound (B1). Even if it is blended in an amount exceeding 1 times by mass, a remarkable improvement in the adhesion improving effect cannot be expected, but further, the number of moles of the hydrogen atom bonded to the silicon atom of the (B2) compound is the component (A). The amount of the (B2) compound corresponding to 0.5 to 10 times the number of moles of the alkenyl group of the above can be optionally added. This is desirable because the cure property of the composition can be further improved.

Specific examples of the (B2) compound include the following.

More preferably, a compound having the following average structural formula can be mentioned.

(B3) component As the component (B), the component (B3) can be further contained. The component (B3) has at least two alkenyl groups in one molecule, the alkenyl group content is an amount corresponding to 5 to 500 times the alkenyl group content of the component (A), and the component (B3) has an epoxy group. It is a compound having a viscosity of less than 0.5 Pa · s at 25 ° C.

The component (B3) is blended as a component that improves the curability of the composition and the adhesion of the obtained cured film to the substrate immediately after curing. The effect of improving the curability and the adhesion to the substrate by the addition of the component (B3) can be obtained by a large difference in viscosity and alkenyl group content from the component (A). The component (A) is a high-viscosity organopolysiloxane, and the molecular weight is increased by a slight cross-linking reaction. Therefore, as the reaction proceeds, the movement of molecules in the composition is restricted, and unreacted alkenyl groups and SiH groups may remain. On the other hand, the component (B3) has a higher alkenyl group content and a lower viscosity than the component (A). Therefore, the restrictions on molecular movement in the composition are small, and the reactivity with the SiH group is excellent, so that the curability can be improved. Further, since the remaining SiH groups are reduced, a light peeling effect can be obtained. Further, as the cross-linking reaction proceeds, the cross-linking density increases, so that it is presumed that the adhesion to the base material immediately after curing is also improved.

The number of alkenyl groups in one molecule of the component (B3) is two or more, which is an amount corresponding to 5 to 500 times the alkenyl group content contained in the component (A), preferably 15 to 400 times. If the amount of the alkenyl group in one molecule of the component (B3) is 5 to 500 times the content of the alkenyl group contained in the component (A), the obtained cured film is cured while maintaining the light peeling effect. Immediately after, the adhesion to the base material can be sufficiently improved.

Here, the alkenyl group contained in the component (B3) is preferably an alkenyl group having 2 to 12 carbon atoms, and-(CH ₂ ) _x -CH = CH ₂ (x is an integer of 0 or 1 to 10). More preferably, it is a group represented by-(C = O) -CH = CH ₂ or -O- (C = O) -CH = CH _2. Specific examples thereof include a vinyl group, a propenyl group, a butenyl group, a hexenyl group, an octenyl group, a decenyl group, an acryloyl group and an acryloyloxy group. Further, the methylene chain may contain an ether bond, and examples thereof include-(CH ₂ ) _2- O-CH ₂ -CH = CH ₂ , -(CH ₂ ) _3- O-CH ₂ -CH = CH _2. Be done. Industrially, a vinyl group and an acryloyloxy group are more preferably used.

Further, the viscosity of the component (B3) at 25 ° C. is less than 0.5 Pa · s, and 0.3 Pa · s. It is more preferably s or less. When it is less than 0.5 Pa · s, the effect of improving the adhesion to the base material can be sufficiently obtained. The lower limit of the viscosity of the component (B3) at 25 ° C. is not particularly limited, but can be, for example, 0.005 Pa · s.

As the component (B3), a hydrocarbon having at least two alkenyl groups in one molecule and may contain a hydroxyl group, or may contain an aryl group or an oxygen atom (ether bond, ester bond, etc.). It is preferably a compound or an organopolysiloxane represented by the following general formula (6).

In the above formula (6), R ⁶ may be the same or different, an unsubstituted or substituted monovalent hydrocarbon group having 1 to 20 carbon atoms having no aliphatic unsaturated bond, or a monovalent hydrocarbon group having 2 to 12 carbon atoms. It is an alkenyl group that may be mediated by an oxygen atom, and at least two of ^{R 6 are alkenyl groups.}

As the monovalent hydrocarbon group having 1 to 20 carbon atoms which does not have the aliphatic unsaturated bond, specifically, an alkyl having 1 to 6 carbon atoms such as a methyl group, an ethyl group, a propyl group and a butyl group is preferable. A cycloalkyl group having 5 to 8 carbon atoms, a phenyl group, a trill group or the like, preferably an aryl group having 6 to 10 carbon atoms, a benzyl group or the like, preferably an aralkyl group having 7 to 10 carbon atoms. , Or a hydroxypropyl group, a cyanoethyl group, a 3-chloropropyl group, 3,3, in which a part or all of the hydrogen atoms bonded to the carbon atom of these groups are replaced with a hydroxy group, a cyano group, a halogen atom, or the like. Examples thereof include monovalent hydrocarbon groups having 1 to 10 carbon atoms selected from 3-trifluoropropyl groups and the like, but from the viewpoint of releasability, alkyl groups and aryl groups are preferable, and methyl groups and ethyl groups are further used. , Apropyl group and a phenyl group are more preferable.

As the alkenyl group in which an oxygen atom having 2 to 12 carbon atoms may be interposed, the same alkenyl group as the above-mentioned alkenyl group having 2 to 12 carbon atoms can be exemplified. Among these, a vinyl group and an alkenyloxy group are preferable.

M', n', o', and p'in the above formula (6) are selected from positive numbers in the above viscosity range, but in particular, m'is an integer of 2 or more, preferably 2 to 100, n. 'Is 0 or more, preferably 0 to 500, more preferably 0 to 300, still more preferably an integer of 0 to 140, o'is 0 or more, preferably an integer of 0 to 30, p'is 0 or more, preferably 0. An integer of ~ 30, with 2 ≦ m'+ n'+ o'+ p'≦ 502, preferably 2 ≦ m'+ n'+ o'+ p'≦ 300, and more preferably 2 ≦ m'+ n'+ o'+ p. '≤150.
The organopolysiloxane represented by the above formula (6) may be linear, branched, or cyclic.

More preferably, the component (B3) is a partially hydrolyzed condensate of an alkoxysilane mixture containing 10 mol% or more of an organoalkoxysilane represented by the following general formula (6-1), and is linear or branched. And / or a compound having a cyclic siloxane structure, a mixture thereof.
Alkenyl-Si (OR11) ₃ ... (6-1)
(In the formula, Alkenyl is a monovalent organic group having an alkenyl group, and R11 may be the same or different, and contains an unsubstituted or substituted oxygen atom having 1 to 20 carbon atoms having no aliphatic unsaturated bond. Hydrocarbon groups and hydroxyl groups that may be contained.)

When the component (B3) is blended, the number of moles of hydrogen atom bonded to the silicon atom in the composition of the present invention is 0.5 with respect to the total number of moles of alkenyl groups of the component (A) and the component (B3). The amount is preferably about 10 times. Here, the hydrogen atom bonded to the silicon atom can form, for example, a Si—H group. Therefore, the hydrogen atom of the Si—H group of the compound (B2) is contained in the hydrogen atom bonded to the silicon atom in the composition. When the composition of the present invention contains the component (C) described below, the hydrogen atom bonded to the silicon atom in the composition further contains the hydrogen atom bonded to the silicon atom of the component (C).

The blending amount when the component (B3) is blended can be, for example, in the range of 0.1 to 10 parts by mass with respect to 100 parts by mass of the organopolysiloxane of the component (A), preferably 0.1. It is in the range of ~ 5 parts by mass. By setting the blending amount of the component (B3) to 0.1 to 10 parts by mass with respect to 100 parts by mass of the component (A), the adhesion to the base material can be sufficiently enhanced while maintaining the light peeling effect.

Specific examples of the component (B3) include the following.

More preferably, the following can be mentioned.

[(C): Organohydrogenpolysiloxane]
The silicone composition for a release sheet of the present invention may further contain (C) an organohydrogenpolysiloxane different from the compound (B2), which has at least two hydrogen atoms bonded to silicon atoms in one molecule. can. For the composition of the present invention, component (C) is an optional component.

The organohydrogenpolysiloxane of the component (C) has at least two hydrogen atoms bonded to a silicon atom (hereinafter, also referred to as “SiH group”) in one molecule, and the SiH group, the component (A) and any of them. A cured film is formed by an addition reaction with the alkenyl group in the component (B3).

The organohydrogenpolysiloxane of the component (C) is not particularly limited as long as it is different from the compound (B2) having at least two hydrogen atoms bonded to silicon atoms in one molecule. As a specific difference from the compound (B2), for example, the amount having a Si—H group is less than 1.3 mol / 100 g.

Examples of the component (C) include those represented by the following average composition formula (7).

R ⁷ _s H _t SiO _{(4-st) / 2} (7)
In the above formula (7), R ⁷ is an unsubstituted or substituted monovalent hydrocarbon group having no aliphatic unsaturated bond, which may be the same or different, and specifically, a methyl group, an ethyl group, and the like. An alkyl group having 1 to 6 carbon atoms such as a propyl group and a butyl group, a cycloalkyl group having 5 to 8 carbon atoms such as a cyclohexyl group, and an aryl having 6 to 10 carbon atoms such as a phenyl group and a tolyl group are preferable. A group, a benzyl group, or the like, preferably an aralkyl group having 7 to 10 carbon atoms, or a hydroxy group in which a part or all of hydrogen atoms bonded to a carbon atom of these groups are replaced with a hydroxy group, a cyano group, a halogen atom, or the like. Examples thereof include a propyl group, a cyanoethyl group, a 3-chloropropyl group, a 3,3,3-trifluoropropyl group and the like. Among them, an alkyl group and an aryl group are preferable, and a methyl group is more preferable from the viewpoint of improving the addition reaction rate.

s is a positive number of 0.1 to 2, preferably 0.2 to 1.5, t is a positive number of 0.1 to 3, preferably 0.2 to 2, and s + t is 3.1 or less. , Especially satisfying 0.5 to 2.7.

Examples of the organohydrogenpolysiloxane represented by the above formula (7) are R ⁷ HSiO _2/2 units (R ⁷ is the same as above, the same applies hereinafter), HSiO _3/2 units, and R ⁷ ₂ HSiO _{1 A polymer having at least one of / 2} units and optionally further containing at least one of R ⁷ ₂ SiO _2/2 units, R ⁷ SiO _3/2 units, and R ⁷ ₃ SiO _1/2 units. Copolymers are exemplified, but it is ^{preferable that the total number of R 7} HSiO _2/2 units or R ⁷ ₂ HSiO _1/2 units is at least 2 in one molecule, preferably 10 to 100. Further, _4/2 units of SiO may be contained in an arbitrary amount.

The content of the SiH group is preferably 0.1 to less than 1.3 mol / 100 g, particularly preferably 0.2 to 1.3 mol / 100 g in the organopolysiloxane of the component (C).

This organohydrogenpolysiloxane may be linear, branched, cyclic, or a mixture thereof.

Further, the viscosity of the component (C) at 25 ° C. is preferably 0.001 to 10 Pa · s, particularly 0.005 to 5 Pa · s. When the viscosity of the component (C) is 0.001 to 10 Pa · s, appropriate curability and workability can be achieved at the same time.

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

The blending amount of the component (C) is preferably such that the number of moles of hydrogen atoms bonded to silicon atoms corresponds to 0.5 to 10 times the number of moles of alkenyl groups in the composition. It is particularly preferable that the amount corresponds to about 5 times. In the composition, the number of moles of the hydrogen atom bonded to the silicon atom is an amount corresponding to 0.5 to 10 times the number of moles of the alkenyl group, so that the composition is cured while maintaining light peelability. The properties and adhesion to the base material can be further improved.

As explained earlier, since the compound (B2) contains a Si—H group, it contains a hydrogen atom bonded to a silicon atom. Therefore, when the component (C) is contained, the hydrogen atom bonded to the silicon atom in the composition includes the hydrogen atom bonded to the silicon atom of the component (C) and the compound (B2). Further, as described above, when the composition of the present invention contains the component (B3), the number of moles of hydrogen atoms bonded to the silicon atom in the composition of the present invention is the same as that of the component (A). B3) The amount is preferably 0.5 to 10 times the total number of moles of alkenyl groups with the component. That is, when the composition of the present invention contains the component (B3) and the component (C), the component (C) and the compound (B2) with respect to the total number of moles of alkenyl groups of the component (A) and the component (B3). The total number of moles of hydrogen atoms bonded to silicon atoms is preferably in the range of 0.5 to 10 times, particularly 1 to 5 times.

Further, at this time, the blending amount of the component (C) is preferably 0.1 to 30 parts by mass with respect to 100 parts by mass of the component (A) in that an appropriate crosslink density can be obtained, and is 0.5. It is more preferably to 15 parts by mass, and further preferably 0.5 to 10 parts by mass.

[(D): Platinum group metal catalyst]
The platinum group metal-based catalyst of the component (D) is a catalyst for promoting the addition reaction between the components (A) and (B3) and the compound (B2) and the component (C), and causes a so-called hydrosilylation reaction. Anything known to those skilled in the art can be used as a facilitator. Examples of such platinum group metal-based catalysts include platinum-based, palladium-based, rhodium-based, and ruthenium-based catalysts, and among these, platinum-based catalysts are particularly preferably used. Examples of the platinum-based catalyst include chloroplatinic acid, an alcohol solution or aldehyde solution of chloroplatinic acid, a complex of chloroplatinic acid and various olefins or vinylsiloxanes, and various olefins or vinylsiloxane complexes of platinum.
The blending amount of the component (D) is the amount of the catalyst, but in order to obtain a good cured film, the mass of the platinum group metal is in the range of 10 to 1,000 ppm, particularly 20 to 500 ppm with respect to the mass of the component (A). Is preferable.

[(E): Organic solvent for dilution]
The silicone composition of the present invention may contain an organic solvent for dilution as an optional component. Specifically, 0 to 20,000 parts by mass of the organic solvent of the component (E) is used with respect to 100 parts by mass of the component (A).

The silicone composition of the present invention may be a solvent-free composition obtained by blending a predetermined amount of the above-mentioned components (A), (B) and (D), and an arbitrary component. By diluting with an organic solvent, practical advantages such as improvement of coating workability, improvement of coating film condition such as thickness of coating film and surface finish condition can be obtained.

Examples of usable organic solvents include 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, ethyl acetate and acetic acid. Examples thereof include ester compounds such as butyl and ether compounds such as diisopropyl ether and 1,4-dioxane, but any compound that can dissolve silicone may be used. It is also possible to use it by dispersing and diluting it in water at an arbitrary ratio.

When the component (E) is blended, the blending amount is preferably 100 to 20,000 parts by mass, particularly 200 to 10,000 parts by mass with respect to 100 parts by mass of the component (A). By setting the blending amount of the component (E) to 100 to 20,000,000 parts by mass, the above-mentioned advantages due to dilution can be sufficiently obtained.

[(F) Peeling force control component]
Further, the composition of the present invention can contain a peeling force control component (F). As the component (F), the following component (F1) and / or the following component (F2) can be used, and the blending amount is 0.1 to 20 parts by mass with respect to 100 parts by mass of the component (A). By containing the component (F) in this amount, the peeling force can be appropriately controlled while maintaining the adhesion to the base material.

(F1): Peeling force control component containing an acrylic-silicone graft copolymer (F1) component is a peeling force control component containing an acrylic-silicone graft copolymer, and by blending the component, A very small peeling force can be obtained, and an excellent cured film (peeling film) having a high residual adhesive rate of the peeled adhesive sheet can be provided.

The acrylic-silicone graft copolymer used in the present invention includes an organopolysiloxane compound (a) having an acrylic group and / or a methacryl group (hereinafter, also referred to as (meth) acrylic group) and one in one molecule. It is a copolymer having a weight average molecular weight of 1,000 to 100,000, which is obtained by radically polymerizing a radically polymerizable monomer (b) having a radically polymerizable group of.

The weight average molecular weight of the copolymer is 1,000 to 100,000 in terms of polystyrene based on the measurement results of gel permeation chromatography (hereinafter abbreviated as "GPC") using toluene as a developing solvent, and is preferably 1. , 500 to 50,000, more preferably 2,000 to 30,000. When the weight average molecular weight is 1,000 to 100,000, both a high residual adhesion rate and excellent dispersibility in the silicone composition can be achieved.

[Component (a): Organopolysiloxane compound having a (meth) acrylic group]
The organopolysiloxane compound (a) used in the present invention is not particularly limited as long as it has a (meth) acrylic group, but is a radically polymerizable monomer (b) having one radically polymerizable group in one molecule. A radically polymerizable silicone macromonomer represented by the following general formula (3) from the viewpoints of ease of copolymerization with, ease of synthesis of the organopolysiloxane compound itself, and the effect of the peeling force controlling component. It is preferable that there is.

In the above general formula (3), R ² is a hydrogen atom or a methyl group, and X is a group (divalent functional group) selected from an oxygen atom, an NH group and a sulfur atom.

Y is a divalent hydrocarbon group having 1 to 12 carbon atoms, preferably 1 to 10 oxygen atoms, and specifically, a methylene group, an ethylene group, and a propylene group (trimethylethylene group, methylethylene group). ), Butylene group (tetramethylene group, methylpropylene group), alkylene group such as hexamethylene group, octamethylene group, arylene group such as phenylene group, combination of two or more of these groups (alkylene / arylene group, etc.), -CH ₂ CH _2- O-CH ₂ CH _2- , -CH ₂ CH _2- O-CH ₂ CH _2- O-CH ₂ CH _2- , -CH (CH ₃ ) CH _2- O-CH (CH ₃₎ ) CH _2- , -CH ₂ CH ₂ CH ₂ CH _2- O-CH ₂ CH ₂ CH ₂ CH _2-, and the like. As Y, an ethylene group, a propylene group, and a butylene group are preferable.
f is an integer of 0 to 1,000, preferably 0 to 500, and more preferably 0 to 200.

R ³ may be the same or different, with 1 to 20 carbon atoms, preferably 1 to 18 unsubstituted or substituted monovalent hydrocarbon groups, hydrogen atoms, hydroxyl groups, 1 to 10 carbon atoms, preferably 1 to 8 carbon atoms. Alkoxy group of, or a substituent represented by the following general formula (4).

(In the formula, R ⁴ may be the same or different, preferably an unsubstituted or substituted monovalent hydrocarbon group having 1 to 20 carbon atoms, preferably 1 to 18 carbon atoms, a hydrogen atom, a hydroxyl group, or 1 to 10 carbon atoms. Is an alkoxy group of 1 to 8. g is an integer of 0 to 300.)

Here, as the ^{unsubstituted or substituted monovalent hydrocarbon group having 1 to 20 carbon atoms of R 3} and R ⁴ , specifically, an alkyl group such as a methyl group, an ethyl group, a propyl group or a butyl group, or a cyclohexyl group. Cycloalkyl group such as, phenyl group, aryl group such as tolyl group, aralkyl group such as benzyl group and phenethyl group, or part or all of hydrogen atom bonded to carbon atom of these group is hydroxy group, cyano Examples thereof include a hydroxypropyl group substituted with a group and a halogen atom, a cyanoethyl group, a 3-chloropropyl group, a 3,3,3-trifluoropropyl group and the like. Specific examples of the alkoxy group having 1 to 10 carbon atoms include a methoxy group, an ethoxy group, a propoxy group, a butoxy group and the like. R ³ is preferably an alkyl group or an aryl group, and more preferably an alkyl group having 1 to 5 carbon atoms. As R ^4, is preferably an alkyl group or an aryl group, more preferably an alkyl group having 1 to 5 carbon atoms.
g is an integer of 0 to 300, preferably 0 to 100, and more preferably 0 to 50.

Specific examples of the component (a) include, but are not limited to, the following. In the following formula, Me, OMe, and Ph represent a methyl group, a methoxy group, and a phenyl group, respectively.

[Component (b): Radical Polymerizable Monomer]
The radically polymerizable monomer (b) used in the present invention may be used alone or in combination of two or more, and is not particularly limited as long as it is a compound having one radically polymerizable group in one molecule. ..

Examples of the component (b) include compounds having one radically polymerizable group in one molecule such as acrylic, methacryl, styrene, silicic acid ester, vinyl, and allyl, and specifically, 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) ) Ester compounds of (meth) acrylic acid such as acrylate, trifluoropropyl (meth) acrylate, perfluorobutylethyl (meth) acrylate, perfluorooctylethyl (meth) acrylate; glycidyl (meth) acrylate, β-methylglycidyl Epyl group-containing radically polymerizable monomers such as (meth) acrylate, 3,4-epylcyclohexylmethyl (meth) acrylate; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) ) Hydroxyl-containing radically polymerizable monomers such as acrylate; γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropyldimethylmethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-methacry Loxypropylmethyldiethoxysilane, γ-methacryloxypropyltributoxysilane, γ-methacryloxypropyltriisopropenoxysilane, γ-acryloxypropyltrimethoxysilane, acryloxymethyltrimethoxysilane, γ-acryloxypropyltriethoxy Radical polymerizable silane compounds such as silane, γ-acryloxypropylmethyldiethoxysilane, styryltrimethoxysilane, styryltriethoxysilane, α-methylstyryltrimethoxysilane; polyoxyalkylene group-containing radically polymerizable monomer; glycerol (meth) ) Acrylic is exemplified.

(F) Considering the light peeling effect and the high residual adhesion rate effect obtained by the peeling force control component, it is preferable to contain an alkyl (meth) acrylate having 1 to 30 carbon atoms, and more preferably a methyl (meth) acrylate. To contain.

[(A) component / (b) component ratio]
The polymerization mass ratio [(a) / (b)] of the organopolysiloxane compound (a) having a (meth) acrylic group and the radically polymerizable monomer (b) having one radically polymerizable group in one molecule is It is preferably in the range of 30/70 to 99/1, more preferably 40/60 to 97/3, and even more preferably 50/50 to 95/5. When the polymerization mass ratio [(a) / (b)] is in the range of 30/70 to 99/1, sufficient compatibility with the silicone composition can be exhibited while maintaining the light peeling effect, thereby exhibiting sufficient compatibility with the silicone composition. , (F) It is possible to prevent the peeling force control component from separating.

[Method for synthesizing acrylic-silicone graft copolymer]
The copolymerization of a monomer raw material containing an organopolysiloxane compound (a) having a (meth) acrylic group and a radically polymerizable monomer (b) having one radically polymerizable group in one molecule is carried out by benzoyl peroxide or dich. Initiation of normal radical polymerization of peroxides such as mil peroxide, lauroyl peroxide, tert-butyl 2-ethylperoxyhexanoate, and azo compounds such as 2,2'-azobis (2-methylbutyronitrile). It is carried out in the presence of an agent, and any of a solution polymerization method, an emulsion polymerization method, a suspension polymerization method and a massive polymerization method can be applied.

In the present invention, among these polymerization methods, the solution polymerization method is particularly preferable because it is easy to adjust the molecular weight of the obtained acrylic-silicone graft copolymer in the optimum range. The solvent used in this case includes 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 ethanol. , Isopropanol, n-butanol, alcohols such as isobutanol, etc., or a mixture of two or more thereof.

The polymerization temperature is preferably in the range of 50 to 180 ° C, particularly preferably in the range of 60 to 120 ° C. Under these temperature conditions, the polymerization reaction can be completed in about 1 to 10 hours. The method of extracting the copolymer from the copolymer solution is not particularly limited, but a method of evaporating the solvent, a method of adding a poor solvent such as water or methanol to the copolymer solution, precipitating the copolymer, and drying the copolymer can be used. Can be mentioned.

When the component (F) is blended, the blending amount is preferably 0.1 to 20 parts by mass, and more preferably 0.1 to 15 parts by mass with respect to 100 parts by mass of the component (A). When the component (F) is contained in the above-mentioned preferable blending amount, both an excellent light peeling effect and an excellent curability can be achieved.

(F2): The linear phenylmethylpolysiloxane (F2) component is a phenylmethylpolysiloxane having a linear structure and may not have a functional group, or has an alkoxy group and / or a silanol group at the terminal. It may be the one that is.

The component (F2) is preferably an organopolysiloxane having a viscosity of 30 mass% toluene diluted at 25 ° C. of 0.01 to 70 Pa · s. By including the (F2) component having a viscosity in such a range, both an excellent peeling force control effect and an excellent productivity can be achieved at the same time.

[Other optional ingredients]
The silicone composition of the present invention can be obtained by blending the above-mentioned component (A), (B1) compound, (B2) compound and (D) component in a predetermined amount, and the above-mentioned component (B3) which is an optional component. The component (C), the component (E) and the component (F) can be further contained in the above-mentioned preferable amounts, and other components can be added in an arbitrary amount as required. What is known as a commonly used silicone-based release agent composition can be added in a usual blending amount.

As other optional components, for example, various organic nitrogen compounds, organic phosphorus compounds, acetylene compounds, oxime compounds, organic chloro compounds and the like can be used as known pot life extenders. For example, acetylene-based alcohols such as 3-methyl-1-butin-3-ol, 3,5-dimethyl-1-hexin-3-ol, 3-methyl-1-penten-3-ol, and phenylbutinol, 3 -Acetylene compounds such as methyl-3-1-pentene-1-in and 3,5-dimethyl-1-hexin-3-in, and reactants of these acetylene compounds with alkoxysilanes or siloxanes or hydrogensilanes. , Vinyl siloxane such as tetramethylvinylsiloxane cyclic body, organic nitrogen compound such as benzotriazole and other organic phosphorus compounds, oxime compounds, organic chromium compounds and the like.

When these compounds are blended, the blending amount may be any amount as long as a good pot life can be obtained, and is generally preferably 0.01 to 10 parts by mass with respect to 100 parts by mass of the component (A), and more preferably 0. It is 05 to 5 parts by mass.

When the composition of the present invention is used as an emulsion composition, a surfactant and a high molecular weight emulsifier can be blended, and an appropriate blending amount is 0.1 to 10 with respect to 100 parts by mass of the component (A). It is in the range of parts by mass.

Further, if necessary, other inorganic components such as antioxidants, pigments, stabilizers, antistatic agents, antifoaming agents, adhesion improvers other than the component (B), thickeners, and silica, which are known as arbitrary components. A filler can be blended.

The silicone composition for a release sheet can be prepared by uniformly mixing the above-mentioned component (A), (B1) compound, (B2) compound, and an arbitrary component in advance, and then adding the component (D) immediately before use. Desirable in terms of pot life.

As another adjustment method, after the component (A) and the optional component are uniformly mixed in advance, the component (B) which is the adhesion improving component (the compound (B1) and the compound (B2), and the optional component (B3)) The method of adding the component (D) immediately before use is advantageous for optimizing the peeling property of the cured product.

Further, a method of adding the (B1) compound and the (B2) compound separately is also preferably used. Since the compounds (B1) and (B2) exert different effects of improving adhesion, it is possible to adjust the addition amount of the compounds (B1) and (B2) to the optimum amount according to the usage situation of the composition. It is desirable from the viewpoint of adhesion, peeling characteristics, and cost.
When used as an additive as described above, it is also possible to use the compound (B1) and / or (B2) as an additive composition mixed with other components.

[Release sheet (coated product)]
The release sheet of the present invention is obtained by applying the silicone composition for a release sheet of the present invention to a paper base material or a film base material and curing it.

The release sheet of the present invention is, for example, a sheet-like base material which is a paper base material or a film base material, and a cured product (cured film) of the silicone composition for a release sheet of the present invention formed on the base material. Can include.

The above-mentioned silicone composition for a release sheet of the present invention is diluted as it is, or further diluted with the above-mentioned solvent for dilution or water in the above-mentioned range, and then a comma coater, a lip coater, a roll coater, a die coater, a knife coater, or a blade. One or both sides of a sheet-like substrate such as paper or film using coating methods such as coating with a coater, rod coater, kiss coater, gravure coater, wire bar coater, screen coating, immersion coating, cast coating, etc. A cured film can be formed on the substrate by applying 0.01 to 100 g / m ² on the substrate and then heating at 50 to 200 ° C. for 1 to 120 seconds. When forming a cured film (release layer) on both sides of the base material, it is preferable to perform the operation of forming the cured film on each side of the base material.

Examples of base materials include polyethylene laminated paper, glassin paper, high-quality paper, kraft paper, clay-coated paper and other coated papers, YUPO and other synthetic papers, polyethylene films, CPP and OPP and other polypropylene films, and polyethylene terephthalate films (PET films). ), Etc. Polyethylene film, polyamide film, polyimide film, polylactic acid film, polyphenol film, polycarbonate film and the like. In order to improve the adhesion between these base materials and the cured film (release layer), a base material surface that has been corona-treated, etched, or plasma-treated may be used.

Hereinafter, the present invention will be specifically described with reference to synthetic examples, examples and comparative examples, but the present invention is not limited to the following examples. In the following example, the part indicates a mass part.

Preparation of silicone composition and release film <Raw materials used>
(A) Ingredient (A-1)
(CH ₂ = CH) ₃ Trivinylsiloxane unit represented by SiO _1/2 0.04 mol%, (CH ₃ ) (CH ₂ = CH) _{Methylvinylsiloxane} unit represented by SiO 2/2 0.4 Organopolysiloxane composed of 99.56 mol% of dimethylsiloxane unit represented by mol% and (CH ₃ ) ₂ SiO _2/2 30 mass% toluene dilution at 25 ° C. Viscocity is 15 Pa · s
Alkenyl group content = 0.01 mol / 100 g

(A-2)
(CH ₃ ) ₂ (CH ₂ = CH) _{Dimethylvinylsiloxane unit represented by SiO 1/2} 0.02 mol%, (CH ₃ ) (CH ₂ = CH) _{Methylvinylsiloxane} represented by SiO 2/2 Organopolysiloxane composed of 3.4 mol% _{unit and 96.58 mol% dimethylsiloxane unit represented by (CH 3} ) ₂ SiO _2/2 30% by mass toluene diluted viscosity at 25 ° C. is 10 Pa ·. s
Alkenyl group content = 0.04 mol / 100 g

(B) Component (B1-1) Compound 3-glycidoxypropyltrimethoxysilane 118.2 parts by mass (0.5 mol), methyltrimethoxysilane 68.1 parts by mass (0.5 mol), water 15 An epoxy group-containing siloxane oligomer obtained by partially hydrolyzing and condensing a mass portion (0.83 mol) in the presence of hydrochloric acid at 70 ° C. for 5 hours has a viscosity of 0.05 Pa · s at 25 ° C.
Average degree of polymerization 5
50 mol% of siloxane unit having an epoxy group bonded to a silicon atom via a carbon atom
The amount of silanol was measured by the Grignard method for quantifying the amount of methane generated using methylmagnesium iodide with a silanol group content of 0.012 mol / 100 g.
Alkoxy group content 0.9 mol / 100 g

(B1-2) Compound Tetraethoxysilane 166.7 parts by mass (0.7 mol), 3-glycidoxypropyltrimethoxysilane 47.3 parts by mass (0.2 mol), and methyltriethoxysilane 17.8. An epoxy group-containing siloxane oligomer obtained by partially hydrolyzing and condensing parts by mass (0.1 mol) and 15 parts by mass (0.83 mol) of water in the presence of hydrochloric acid at 80 ° C. for 5 hours has a viscosity of 0.02 Pa at 25 ° C.・ S
Average degree of polymerization 5
20 mol% of siloxane unit having an epoxy group bonded to a silicon atom via a carbon atom
Silanol group content 0.015 mol / 100 g
Alkoxy group content 1.4 mol / 100 g

(B1-3) Compound 3-Glycydoxypropyltrimethoxysilane 236.3 parts by mass (1 mol) and 9 parts by mass (0.5 mol) of water are partially hydrolyzed at 70 ° C. for 5 hours in the presence of hydrochloric acid. Condensed epoxy group-containing siloxane oligomer with a viscosity of 0.005 Pa · s at 25 ° C.
Average degree of polymerization 2
100 mol% of siloxane unit having an epoxy group bonded to a silicon atom via a carbon atom
Silanol group content 0.015 mol / 100 g
Alkoxy group content 0.9 mol / 100 g

(B1-4) Compound Organopolysiloxane represented by the following formula

(W1 = 42, w2 = 33, Ep ¹ is a 2- (3,4-epoxycyclohexyl) ethyl group, Me is a methyl group)

(B1-5) Compound Organopolysiloxane represented by the following formula

(W = 20, Ep ¹ is a 2- (3,4-epoxycyclohexyl) ethyl group, Me is a methyl group)

(B1-6) Compound (B1-4) Organopolysiloxane in which Ep ^{1 of the} compound is a 3- (2,4-epoxypropyloxy) propyl group.

(B1-7) Compound Organopolysiloxane in which Ep ¹ of the (B1-5) compound is a 3- (2,4-epoxypropyloxy) propyl group.

(B2-1) Compound (CH ₃ ) Organo consisting of 5 mol% of trimethylsiloxane unit represented by ₃ SiO _1/2 and 95 mol% of methylhydrogensiloxane unit represented by _{(CH 3} ) HSiO _2/2 Hydrogen polysiloxane The viscosity at 25 ° C is 0.02 Pa · s.
Si—H group content = 1.5 mol / 100 g
Degree of polymerization 40

(B2-2) Compound (CH ₃ ) 2 mol% of trimethylsiloxane unit represented by ₃ SiO _1/2 , 78 mol% of methylhydrogensiloxane unit represented by _{(CH 3} ) HSiO _{2/2, and (CH 3)} ₃ ) _{Organohydrogenpolysiloxane} _{composed of 20 mol% of dimethylsiloxane unit represented by 2} SiO 2/2 The viscosity at 25 ° C. is 0.1 Pa · s.
Si—H group content = 1.2 mol / 100 g
Degree of polymerization 100

(B3-1) Ingredients Methyltrimethoxysilane 27.2 parts by mass (0.2 mol), 3- (acryloyloxy) propyltrimethoxysilane 187.5 parts by mass (0.8 mol), water 15.0 parts by mass (0.83 mol) was partially hydrolyzed and condensed at 70 ° C. for 5 hours in the presence of hydrochloric acid. An alkenyl group-containing siloxane oligomer had a viscosity of 0.04 Pa · s at 25 ° C.
Average degree of polymerization 6
80 mol% of siloxane unit having an alkenyl group bonded to a silicon atom via a carbon atom
Alkenyl group content 0.24 mol / 100 g
Silanol group content 0.009 mol / 100 g,

(B3-2) Component 54.1 parts by mass (0.45 mol) of dimethyldimethoxysilane, 73.3 parts by mass (0.3 mol) of diphenyldimethoxysilane, 37.1 parts by mass (0.25 mol) of vinyltrimethoxysilane ), 15.3 parts by mass (0.85 mol) of water was partially hydrolyzed and condensed at 70 ° C. for 5 hours in the presence of hydrochloric acid, and the viscosity at 25 ° C. was 0.10 Pa · s.
Average degree of polymerization 7
25 mol% of siloxane unit having an alkenyl group bonded to a silicon atom via a carbon atom
Alkenyl group content 0.078 mol / 100 g
Silanol group content 0.011 mol / 100 g,

(C) Component (C-1)
(CH ₃ ) 2 mol% of trimethylsiloxane unit represented by ₃ SiO _1/2 , 70 mol% of methylhydrogensiloxane unit represented by _{(CH 3} ) HSiO _2/2 _{, and (CH 3} ) ₂ SiO _{2 / Organohydrogenpolysiloxane composed of 28 mol% of dimethylsiloxane unit represented by 2} The viscosity at 25 ° C. is 0.1 Pa · s.
Si—H group content = 1.1 mol / 100 g

(D) Component Platinum-vinylsiloxane complex as a catalyst

(E) Component Toluene and hexane mass ratio 1: 1 mixed solvent

Component (F) Component (F-1) Peeling force control component: Acrylic-silicone graft copolymer obtained by Synthesis Example 1 below

[Synthesis Example 1]
A glass reaction device equipped with a stirrer, a thermometer, a reflux condenser, and a dropping device is charged with 30.0 parts of toluene, heated to 90 to 100 ° C., and then radically polymerizable silicone macro represented by the following formula (8). A mixture of 55.7 parts (0.067 mol) of monomer, 9.8 parts (0.098 mol) of methyl methacrylate, 2.5 parts (0.012 mol) of tert-butyl 2-ethylperoxyhexanoate and 51.8 parts of toluene. The mixture was added dropwise over 4 hours under aeration with nitrogen. Further, after polymerization at 90 to 100 ° C. for 2 hours, 0.4 part (0.002 mol) of tert-butyl 2-ethylperoxyhexanoate was added, and the polymerization was carried out for 2 hours. Then, it was dried in a vacuum dryer under the condition of 150 ° C./10 mmHg to obtain an acrylic-silicone graft copolymer. The polystyrene-equivalent weight average molecular weight by GPC was 12,000.

(F-2) Component (CH ₃ ) 0.7 mol% of trimethylsiloxane unit represented by ₃ SiO _1/2 _{, (CH 3} ) 94.3 mol% of dimethylsiloxane unit represented by ₂ SiO _2/2, Organopolysiloxane consisting of 5 mol% of diphenylsiloxane unit represented by (C ₆ H ₅ ) ₂ SiO _2/2 The viscosity at 25 ° C. is 3.00 Pa · s.

(G component)
Pot life extender: 3-methyl-1-butyne-3-ol

<Examples 1 to 20, Comparative Examples 1 to 20>
Using the components (A) to (E) and (G) shown above as raw materials, a coating composition was prepared by the following procedure.
The components (A) to (C) were placed in a flask according to the compounding ratios shown in Tables 1 and 2, and 3,200 parts of the component (E) and 3 parts of the component (G) were added and stirred to dissolve. The component (D) was added to the obtained solution so as to be 100 ppm in terms of platinum mass with respect to the component (A), and the mixture was stirred and mixed to obtain a composition for coating. A release film (coated product) was prepared and evaluated using this composition by the method described below.

<Examples 21 to 24>
Using the components (A) to (G) shown above as raw materials, a coating composition was prepared by the following procedure.
Ingredients (A) to (C) and (F) were placed in a flask according to the compounding ratio shown in Table 2, and 3,200 parts of component (E) and 3 parts of component (G) were added and stirred to dissolve. The component (D) was added to the obtained solution so as to be 100 ppm in terms of platinum mass with respect to the component (A), and the mixture was stirred and mixed to obtain a composition for coating. A release film (coated product) was prepared and evaluated using this composition by the method described below.

<Evaluation>
[Curability (adhesion immediately after curing)]
The obtained composition was applied to a PET film having a thickness of 38 μm at a solid content of 0.1 g / m ² using a bar coater, and in a hot air dryer at 100 ° C. for a specified number of seconds (30 seconds or 60 seconds). It was heated to form a release agent layer (cured film) to obtain a release film. After rubbing the release agent layer with a finger 10 times, the presence or absence of cloudiness and shedding was visually observed and evaluated according to the following criteria.
A: No cloudiness or shedding was observed in 30 seconds.
B: Cloudy and shedding was observed at 30 seconds, but not at 60 seconds.
C: Cloudy and shedding was observed in 60 seconds.
The results are shown in Tables 1 and 2 below.

[Adhesion]
The obtained composition was applied to a PET film having a thickness of 38 μm at a solid content of 0.1 g / m ² using a bar coater, and heated in a hot air dryer at 120 ° C. for 40 seconds to form a release agent layer. And a release film was obtained. The resulting release film was stored at 25 ° C. and 50% RH for one week or at 60 ° C. and 90% RH for one week. After rubbing the release agent layer with a finger 10 times, the presence or absence of cloudiness and shedding was visually observed and evaluated according to the following criteria.
A: No cloudiness or shedding was observed.
B: Cloudiness is seen, but no dropout is seen.
C: Cloudy or shed.
The results are shown in Tables 1 and 2 below.

[Peeling force]
The compositions obtained in Examples 5 to 7, 13, 18 to 21 and 23, and Comparative Examples 1, 3 and 20 were applied to a PET film having a thickness of 38 μm using a bar coater in a solid content of 0.1 g / m. ² coats were applied and heated in a hot air dryer at 120 ° C. for 40 seconds to form a release agent layer (cured film), which was evaluated according to the FINAT method by the following procedure.

A 25 mm wide adhesive tape (Tesa7475 tape, trade name manufactured by Tesa Tape. Inc) is attached to the surface of the release agent layer and treated at 25 ° C. with ^{a load of 70 g / cm 2} for 20 hours (crimping A) and 70 ° C. A load of 20 g / cm ² was applied to the dryer and heat-treated for 20 hours (crimping B). The treatment was carried out under two crimping conditions. After air cooling for about 30 minutes, the force required to pull and peel the Tesa7475 tape at an angle of 180 ° and a peeling speed of 0.3 m / min using a tensile tester (DSC-500 type tester manufactured by Shimadzu Corporation). (N / 25 mm) was measured.
The results are shown in Table 3 below.

[Residual adhesion rate]
A release agent layer is formed in the same manner as in the above release force evaluation, a 25 mm wide polyester adhesive tape (Nitto 31B, trade name manufactured by Nitto Denko Corporation) is attached to the surface of the release agent layer, and 20 g / in a dryer at 70 ° C. A load of cm ² was applied and heat treatment was performed for 20 hours. Then, the polyester adhesive tape was peeled off from the release agent layer, and the polyester adhesive tape was attached to the SUS stainless steel plate. Next, the polyester adhesive tape was peeled from the SUS stainless steel plate using a tensile tester, and the peeling force F was measured.

Further, instead of the release agent layer, a polyester adhesive tape was attached to a tetrafluoroethylene plate and treated in the same manner, and the release force F ₀ was measured.
Then, the residual adhesive ratio was determined from the formula (peeling force F / peeling force F _{0) × 100 (%).} The higher the residual adhesive ratio, the smaller the influence of contact with the release agent layer on the adhesiveness of the adhesive surface of the adhesive tape, and the reduction in the adhesive force of the adhesive tape after peeling can be suppressed, which is an excellent release agent layer. Can be evaluated as.
The results are shown in Table 3 below.

Peeling force: Peeling speed 0.3 m / min 180 degrees direction Adhesive surface peeling Crimping A: 70 g / cm ² Load 25 ° C for 20 hours Crimping B: 20 g / cm Load 70 ° C for 20 hours Crimping Residual adhesive rate: Nittou 31B Tape bonding , 20g / cm ² load 70 ℃ 20 hours crimping, stick the peeled tape on the SUS board and measure the adhesive strength in the same way as the peeling force after 1 reciprocating crimping of the 2kg tape roller, the blank is the same as the Teflon (registered trademark) board Let 100% be the measured value processed in

From the results of Tables 1 and 2, the compositions of Examples 1 to 24 of the present invention are excellent in curability and can show excellent adhesion to the substrate, and this excellent adhesion is exhibited at high temperature and high humidity. It can be seen that a release agent layer (cured film) that can be maintained for a long period of time could be formed even in a harsh environment. Further, from the results in Table 3, it can be shown that the compositions of Examples 5 to 7, 13, 18 to 21 and 23 of the present invention do not have a heavy peeling force due to the addition of the adhesion improver, and the adhesive tape. It can be seen that it was possible to provide a release agent layer that did not significantly impair the adhesiveness of the material. Similar to the compositions of Examples shown in Table 3, the compositions of Examples 1 to 4, 8 to 12, 14 to 17, 22 and 24 of the present invention also have a peeling force due to the addition of the adhesion improver. It was possible to provide a release agent layer that did not become heavy and did not significantly impair the adhesiveness of the adhesive tape.

On the other hand, the composition of Comparative Example 1 did not contain either the (B1) compound or the (B2) compound. The compositions of Comparative Examples 2 and 3 did not contain the compound (B1). The compositions of Comparative Examples 4 and 19 did not contain the compound (B2). As a result, the release agent layers obtained from the respective compositions of Comparative Examples 1 to 4 and 19 could not maintain the adhesion to the substrate for a long period of time in a harsh environment. Further, from the comparison between Comparative Example 4 and Comparative Example 19, even if the amount of the (B1) compound is increased, if the (B2) compound is not contained, the adhesion to the substrate is maintained for a long period of time in a harsh environment. It turns out that it cannot be done.

In Comparative Examples 5 and 6, the amount of the compound (B1) was 25 parts by mass with respect to 100 parts by mass of the component (A), which was too large. As a result, the release agent layer obtained from the compositions of Comparative Examples 5 and 6 could not maintain the adhesion to the substrate for a long period of time in a harsh environment. On the other hand, in the composition of Comparative Example 20, the amount of the compound (B1) was 0.05 parts by mass with respect to 100 parts by mass of the component (A), which was too small. As a result, the release agent layer obtained from the composition of Comparative Example 20 could not maintain the adhesion to the substrate for a long period of time in a harsh environment.

The (B2-2) compound used in Comparative Examples 7 and 8 had a Si—H group content of 1.2 mol / 100 g. As a result, the release agent layer obtained from the compositions of Comparative Examples 7 and 8 could not maintain the adhesion to the substrate for a long period of time in an environment of 25 ° C. (severe).

The (B1-3) compound used in Comparative Examples 9 and 10 had an average degree of polymerization of 2. As a result, the release agent layer obtained from the compositions of Comparative Examples 9 and 10 could not maintain the adhesion to the substrate for a long period of time in a harsh environment.

Each of the compounds (B1-4) to (B1-7) used in Comparative Examples 11 to 18 did not contain a silanol group and an alkoxy group. As a result, the release agent layer obtained from the compositions of Comparative Examples 11 to 18 could not maintain the adhesion to the substrate for a long period of time in a harsh environment.

The present invention is not limited to the above embodiment. The above-described embodiment is an example, and any object having substantially the same configuration as the technical idea described in the claims of the present invention and exhibiting the same effect and effect is the present invention. Is included in the technical scope of.

Claims

An addition-curing type silicone composition for a release sheet,
(A) It has at least two alkenyl groups in one molecule, has an alkenyl group content of 0.001 to 0.2 mol / 100 g, and has a 30 mass% toluene dilution viscosity at 25 ° C. of 0.01 to 70 Pa. Organopolysiloxane: 100 parts by mass;
(B) Component containing the following (B1) compound and (B2) compound (B1) 10 mol% or more of a siloxane unit having a glycidyl group and / or a glycidoxy group bonded to a silicon atom via a carbon atom in one molecule. Organopolysiloxane containing 0.002 to 0.02 mol / 100 g of silanol groups, 0.5 to 2.5 mol / 100 g of alkoxy groups, and an average degree of polymerization of 3 to 50: 0.1 ~ 20 parts by mass;
(B2) Organohydrogensiloxane having 1.3 mol / 100 g or more of Si—H groups and a degree of polymerization of 10 to 100: parts by mass corresponding to 0.02 to 1 times the mass part of the compound (B1). ;
(D) Platinum group metal catalyst: catalyst amount;
(E) Organic solvent: A silicone composition for an addition-curable release sheet, which contains 0 to 20,000 parts by mass.
In addition
(C) Organohydrogenpolysiloxane different from the compound (B2) having at least two hydrogen atoms bonded to a silicon atom in one molecule: bonded to the compound (B2) and the silicon atom of the component (C). The total number of moles of hydrogen atoms produced corresponds to 0.5 to 10 times the number of moles of alkenyl groups in the composition;
The silicone composition for a release sheet according to claim 1, wherein the silicone composition comprises.
The compound (B1) is an organoalkoxysilane represented by the following general formula (1-1) and an organoalkoxy represented by the following general formulas (1-2), (1-3) and (1-4). Claim 1 or 2 which is a partially hydrolyzed condensate with at least one of silanes and is an organopolysiloxane having a linear, branched siloxane or cyclic siloxane structure, or a mixture thereof. The silicone composition for a release sheet according to the above.

(In the formula, R1 is a hydrocarbon group or a hydrogen atom which may contain an unsubstituted or substituted oxygen atom having 1 to 10 carbon atoms which does not have an aliphatic unsaturated bond and may be the same or different. R12 is an unsaturated or substituted hydrocarbon group having 1 to 20 carbon atoms, and n is an integer of 3 to 10).
Any 1 of claims 1 to 3, wherein the compound (B2) is an organohydrogensiloxane represented by the following general formula (2-1) or (2-2), or a mixture thereof. The silicone composition for a release sheet according to the item.
(R12) 3 Si-{(R12) HSiO} m- Si (R12) 3 ... (2-1)
(R12) 2 HSi-{(R12) HSiO} m- SiH (R12) 2 ... (2-2)
(In the formula, R12 is an unsubstituted or substituted hydrocarbon group having 1 to 20 carbon atoms, which may be the same or different, and m is an integer of 2 to 100).
The component (B) further contains 0.1 to 10 parts by mass of the component (B3), the component (B3) has at least two alkenyl groups in one molecule, and the alkenyl group content is the component (A). It is a compound having an amount corresponding to 5 to 500 times the alkenyl group content of the above, having no epoxy group, and having a viscosity of less than 0.5 Pa · s at 25 ° C.
The number of moles of hydrogen atom bonded to a silicon atom in the composition is an amount corresponding to 0.5 to 10 times the total number of moles of alkenyl groups of the component (A) and the component (B3). The silicone composition for a release sheet according to any one of claims 1 to 4, wherein the silicone composition is characterized by the above.
Further, the claim is characterized in that the peeling force control component (F) contains the following (F1) component and / or the following (F2) component in an amount of 0.1 to 20 parts by mass with respect to 100 parts by mass of the component (A). Item 6. The silicone composition for a release sheet according to any one of Items 1 to 5.
(F1) (a) Organopolysiloxane compound having an acrylic group and / or a methacryl group represented by the following general formula (3), and (b) radical polymerizable having one radically polymerizable group in one molecule. A peeling force control component containing an acrylic-silicone graft copolymer having a weight average molecular weight of 1,000 to 100,000, which is obtained by radical polymerization of a monomer;

[In the formula, R 2 is a hydrogen atom or a methyl group, X is a group selected from an oxygen atom, an NH group and a sulfur atom, and Y is a divalent oxygen atom having 1 to 12 carbon atoms. A hydrocarbon group, R 3 may be the same or different, an unsubstituted or substituted monovalent hydrocarbon group having 1 to 20 carbon atoms, a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 10 carbon atoms, or the following. General formula (4)

(In the formula, R 4 is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 20 carbon atoms, a hydrogen atom, a hydroxyl group, or an alkoxy group having 1 to 10 carbon atoms, which may be the same or different. Is an integer from 0 to 300.)
It is a substituent represented by. f is an integer from 0 to 1,000. ]
(F2) Linear phenylmethylpolysiloxane.
A release sheet obtained by applying the silicone composition for a release sheet according to any one of claims 1 to 6 to a paper substrate or a film substrate and curing the composition.