JPWO2019216141A1 - Method for producing cationically polymerizable organopolysiloxane, heavy release additive, releaseable radiation-curable silicone composition, release sheet and method for producing the same. - Google Patents

Abstract

Organopolysiloxane resin (a1) and organohydro with Q and M units as the main components, M / Q of 0.6 to 1.2 in molar ratio, and SiOH group content of 0% by mass or more and 1.2% by mass or less. A condensate obtained by dehydrogenating a gen (poly) siloxane (a2) in the presence or absence of a cyano group-containing organic compound (a3), or a mixture of the above (a1) and (a2). Obtained by blending the alkenyl group-containing epoxy compound (a4) in the presence of (a3) and subjecting the condensate and / or the SiH group in the above (a2) to the alkenyl group in the above (a4). The cationically polymerizable organopolysiloxane is more potent than the conventional cationically polymerizable organopolysiloxane, and can suppress an increase in viscosity and gelation. Therefore, the cationically polymerizable organopolysiloxane is suitably used as a heavy peeling additive for a release sheet.

Description

The present invention is a method for producing a cationically polymerizable organopolysiloxane that is suitably used as a heavy peeling additive for a release sheet, and a peelability using the obtained cationically polymerizable organopolysiloxane as a heavy release additive for a release sheet. It relates to a radiation-curable silicone composition, a release sheet using the composition, a method for producing the same, and the like.

The organopolysiloxane composition is applied to the surface of a base material such as various types of paper, laminated paper, synthetic film, transparent resin, and metal foil, and a cured film is formed by a cross-linking reaction to peel off adhesive or adhesive substances. Release sheets such as release papers and release films having properties are manufactured.

There are various methods for curing the organopolysiloxane composition, and condensation reactions using organometallic compounds, vulcanization using organic peroxides, hydrosilylation reactions using platinum group metal catalysts, and the like are recognized. However, the above curing method requires heating, and curing at a lower temperature or room temperature is required in order to improve productivity and save energy. Recently, as an application for electronic members and optical materials, applications using a base material having poor heat resistance such as polyethylene terephthalate (PET) film are increasing.

Therefore, as a method of giving curing energy other than heat without heating, a curing method using radiation is attracting attention.
The curing method by radiation is radical polymerization using (meth) acrylic-modified polysiloxane, en-thiol reaction using mercapto-modified organopolysiloxane and alkenyl-modified organopolysiloxane, and cation by opening the epoxy group of epoxy-modified polysiloxane. Curing using polymerization and the like can be mentioned.

Among them, curing using cationic polymerization by opening the epoxy group of the epoxy-modified polysiloxane is not affected by curing inhibition by oxygen and does not require heat for the curing reaction, so that it can be used as a film substrate having poor heat resistance. On the other hand, because it can be coated and has excellent convenience and operability, it is particularly used as a backing agent for adhesive tapes, a release paper for adhesive labels, and a coating agent for fixing fastener tapes using tape. The market is expected to expand in the future.

In general, most of the release sheets used for labels and manufacturing process paper are surface-treated with a silicone composition containing organopolysiloxane as a main component, and the release sheet silicone composition used for the release sheet is not included in the release sheet. Those having various peeling powers are required according to the purpose.

For example, a release sheet having heavy release or variable release characteristics may be required. In order to prevent the label from peeling from the release sheet, it is desirable that the silicone release agent is heavy peeling. In addition, there is a difference in peeling power like a double-sided peelable laminated product obtained by applying a lightly peelable silicone composition as a light surface on one side and a heavy peelable silicone composition as a heavy surface on the other side and curing it. The attached laminate is required to have a peeling force that does not easily peel off on the heavy surface side. Further, when the heavy peeling characteristic is required, the peeling force does not change with the passage of time, and the characteristic of the peeling sheet or the like does not change.

Compositions to which an organopolysiloxane resin has been added are widely used for applications that require heavy peeling. However, when the organopolysiloxane resin is simply mixed, the heavy peeling effect is not sufficient, and even if a large amount is added, the desired peeling force may not be obtained. Therefore, it has been studied to produce a release sheet having a high heavy release effect by reacting and using an organosiloxane resin.

In Japanese Patent No. 3488272 (Patent Document 1), (A) component is (SiO _4/2 ) unit (Q unit), (R ₃ SiO _1/2 ) unit (M unit), and epoxy functional M unit. , (R ₂ SiO) unit (D unit) or (RSiO _3/2 ) unit (T unit), and contains M unit and epoxy per 10 copies in total of Q unit, D unit, and T unit. 20 to 80% by mass of the cationically polymerizable organopolysiloxane having a total of at least 5 parts of the functional M unit, and 80 to 80 to 80% of the cationically polymerizable terminal organopolysiloxane containing the epoxy functional M unit as the component (B). An ultraviolet curable epoxy silicone composition containing 20% by mass and containing a cationically polymerizable organopolysiloxane having an epoxy equivalent of more than 1,000 and an onium-based photocatalyst has been proposed.

In the example of Patent Document 1, although the change in peeling force with time is small, _{60 parts of the organosiloxane resin containing (SiO 4/2} ) unit and (R ₃ SiO _1/2 ) unit and 50% by mass of the compound are contained. It is necessary to add a large amount as described above, and it is considered that the heavy peeling effect of the heavy peeling component containing the organopolysiloxane resin in Patent Document 1 is small.

In Japanese Patent No. 3661743 (Patent Document 2), an organohydrogensiloxane is used as opposed to an OH group of an OH group-containing organopolysiloxane having _{M units, Q units, and (HO) SiO 3/2 units as main constituent units.} After a dehydrogenation condensation reaction using an excess amount of SiH groups, the SiH groups remaining in the obtained reaction product are subjected to an addition reaction with the alkenyl groups of the compound containing an epoxy group and an alkenyl group. A method for producing a cationically polymerizable organopolysiloxane and a heavy peeling additive obtained from the method have been proposed.

In the examples of Patent Document 2, although the change in peeling force with time is small, a certain heavy peeling effect is obtained, but it is not in the range where the further heavy peeling characteristics required in recent years can be satisfied.
In addition, since the OH group-containing organopolysiloxane has a hydroxyl group, depending on the production conditions, an excessive dehydrogenation condensation reaction with the SiH group or the epoxy group of the cationically polymerizable organopolysiloxane, which is the target product, may open the ring for the purpose. There is a very high possibility that the substance will increase in viscosity and gel.

Japanese Patent No. 5786798 (Patent Document 3) mainly contains polydiorganosiloxane having one or more hydroxyl groups or hydrolyzable groups in one molecule having an average degree of polymerization of 100 to 3,000, and M units and Q units. A polyorganosiloxane resin in which the ratio of M units to Q units as a component is 0.6 to 1.2 as a molar ratio, and the total content of hydroxyl groups and hydrolyzable groups is 2.1% by mass or more and less than 10% by mass. A radiation-curable silicone composition using a heavy-release additive composed of a condensation reaction product obtained by dehydrating and condensing the above has been proposed.

In the examples of Patent Document 3, the change in peeling force with time is small, and a constant heavy peeling effect is obtained even when the amount of the heavy peeling additive added is small, but one or more in one molecule of the heavy peeling component. Condensation reaction in which a polydiorganosiloxane having a hydroxyl group or a hydrolyzable group and a polyorganosiloxane resin having a total content of a hydroxyl group and a hydrolyzable group of 2.1% by mass or more and less than 10% by mass are subjected to a dehydration condensation reaction. Since the product is a non-reactive component that does not participate in curing, it is considered that as the amount of the heavy release additive added increases, the amount of the transition component increases and the residual adhesion rate decreases.

Japanese Patent No. 3488272 Japanese Patent No. 3661743 Japanese Patent No. 5786798

The present invention has been made in view of the above circumstances, and is obtained by a method for producing a cationically polymerizable organopolysiloxane, which can suppress an increase in viscosity and gelation and is suitably used as a heavy release additive for a release sheet. An object of the present invention is to provide a peelable radiation-curable silicone composition using the obtained cationically polymerizable organopolysiloxane as a heavy peeling additive for a peeling sheet, a peeling sheet using the composition, a method for producing the same, and the like. To do.

A cationically polymerizable organopolysiloxane containing an epoxy group is usually obtained by an addition reaction of an organohydrogenpolysiloxane and an epoxy compound containing an alkenyl group, but the addition reaction may involve a polymerization reaction of an epoxy group as a side reaction. , The viscosity of the product may be significantly increased or gelled. In particular, the addition reaction between the organohydrogenpolysiloxane containing the hydroxyl group-containing organopolysiloxane resin and the alkenyl group-containing epoxy compound causes an increase in viscosity due to a side reaction during the addition reaction due to the influence of the hydroxyl group-containing organopolysiloxane resin. The tendency of gelation was remarkable.

As a result of diligent studies to achieve the above object, the present inventors have conducted a cyano group-containing organic compound in an addition reaction between an organohydrogenpolysiloxane containing a hydroxyl group-containing organopolysiloxane resin and an alkenyl group-containing epoxy compound. By adding the above, the increase in viscosity and gelation of the product cationically polymerizable organosiloxane can be suppressed, and the heavy peeling additive using the present cationically polymerizable organopolysiloxane does not contain a cyano group-containing organic compound. It was found that the heavy peeling effect is stronger than that of the heavy peeling additive using the cationically polymerizable organopolysiloxane produced by the same production method.

That is, (SiO _4/2 ) unit and (R ¹ ₃ SiO _1/2 ) unit (in the formula, R ¹ is 1 of 1 to 12 carbon atoms which are the same or different and do not have a hydroxyl group or an aliphatic unsaturated bond. is a valence hydrocarbon group.) as a main component, a (0.6 to 1.2 ratio of ^{_{SiO 4/2) (R 1 3 SiO}} 1/2) units to units molar ratio, to the silicon atom Dehydrocarbonation of an organopolysiloxane resin having a total content of hydroxyl groups to be bonded of 0% by mass or more and 1.2% by mass or less and an organohydrogen (poly) siloxane in the presence or absence of a cyano group-containing organic compound. In the presence of a cyano group-containing organic compound, an alkenyl group-containing epoxy compound is added to the condensed product obtained by the condensation reaction or a mixture of the above-mentioned organopolysiloxane resin and an organohydrogen (poly) siloxane, and the above-mentioned condensate and / Alternatively, the cationically polymerizable organopolysiloxane obtained by subjecting the SiH group in the organohydrogen (poly) siloxane to the alkenyl group in the alkenyl group-containing epoxy compound undergoes a heavy peeling from the conventional cationically polymerizable organopolysiloxane. It was found that the effect is strong and that the increase in viscosity and gelation can be suppressed.
Furthermore, the peeling sheet obtained by using the peelable radiation-curable silicone composition containing the above-mentioned cationically polymerizable organopolysiloxane as a heavy peeling additive has a strong heavy peeling effect and stable peeling force over time. It has been found and the present invention has been made.

（式中、Ｒ²は同一もしくは異種の、水素原子又は炭素数１〜１０の１価炭化水素基であり、Ｒ²のうち少なくとも１個は水素原子を含む。Ｒ³は同一もしくは異種の、炭素数１〜１０の１価炭化水素基である。ａ≧２、ｂ≧０、ｃ≧０、ｄ≧０、２≦ａ＋ｂ＋ｃ＋ｄ≦３，０００である。またｅ≧１、ｆ≧０、ｅ＋ｆ≧３である。）
（ａ３）下記一般式（３）で示されるシアノ基含有有機化合物、
Ｒ⁴−ＣＮ （３）
（式中、Ｒ⁴は脂肪族不飽和結合を有さない炭素数１〜１５の１価炭化水素基である。）
（ａ４）アルケニル基含有エポキシ化合物。
２．
（ａ１）成分のオルガノポリシロキサン樹脂の水酸基の総含有量が、０質量％以上１．０質量％以下である１記載のカチオン重合性オルガノポリシロキサンの製造方法。
３．
（ａ１）成分のオルガノポリシロキサン樹脂の水酸基の総含有量が、０質量％以上０．８質量％以下である１記載のカチオン重合性オルガノポリシロキサンの製造方法。
４．
（ａ１）成分のオルガノポリシロキサン樹脂の水酸基の総含有量が、０質量％以上０．６質量％以下である１記載のカチオン重合性オルガノポリシロキサンの製造方法。
５．
（ａ３）成分のシアノ基含有有機化合物の沸点が、常圧下で３００℃以下である１記載のカチオン重合性オルガノポリシロキサンの製造方法。
６．
１〜５のいずれかに記載の製造方法により得られたカチオン重合性オルガノポリシロキサンからなる剥離シート用の重剥離添加剤。
７．
１〜５のいずれかに記載の製造方法により得られたカチオン重合性オルガノポリシロキサンを重剥離添加剤として含む剥離性放射線硬化型シリコーン組成物。
８．
７記載の剥離性放射線硬化型シリコーン組成物を基材上に塗布し、放射線照射により硬化させる剥離シートの製造方法。
９．
７記載の剥離性放射線硬化型シリコーン組成物の硬化皮膜を基材上に形成してなる剥離シート。Therefore, the present invention provides the following method for producing a cationically polymerizable organopolysiloxane, a releaseable radiation-curable silicone composition, a release sheet, and a method for producing the same.
1. 1.
A condensate obtained by dehydrocondensing the following component (a1) and (a2) in the presence or absence of the following component (a3), or a mixture of the following component (a1) and component (a2). In the presence of the following component (a3), the following component (a4) is blended with the SiH group remaining in the condensate of the component (a1) and the component (a2) and / or the SiH group in the component (a2). (A4) A method for producing a cationically polymerizable organopolysiloxane, which comprises an addition reaction with an alkenyl group in a component.
(A1) (SiO _4/2 ) unit and (R ¹ ₃ SiO _1/2 ) unit (In the formula, R ¹ is the same or different, and has 1 to 12 carbon atoms that do not have a hydroxyl group or an aliphatic unsaturated bond. monovalent hydrocarbon group.) as a main component, (a 0.6 to 1.2 ratio of _{^{SiO 4/2) (R 1 3 SiO}} 1/2 per unit) units as the molar ratio of hydroxyl group Organopolysiloxane resin with a total content of 0% by mass or more and 1.2% by mass or less,
(A2) Organohydrogen (poly) siloxane represented by the following average composition formulas (1) and / or (2),

(In the formula, R ² is the same or dissimilar hydrogen atom or monovalent hydrocarbon group having 1 to 10 carbon atoms, and ^{at least one of R 2} contains a hydrogen atom. R ³ is the same or dissimilar. It is a monovalent hydrocarbon group having 1 to 10 carbon atoms. A ≧ 2, b ≧ 0, c ≧ 0, d ≧ 0, 2 ≦ a + b + c + d ≦ 3,000. Also, e ≧ 1, f ≧ 0, e + f. ≧ 3)
(A3) A cyano group-containing organic compound represented by the following general formula (3),
R ^4- CN (3)
(In the formula, R ⁴ is a monovalent hydrocarbon group having 1 to 15 carbon atoms having no aliphatic unsaturated bond.)
(A4) Epoxy compound containing an alkenyl group.
2.
(A1) The method for producing a cationically polymerizable organopolysiloxane according to 1, wherein the total content of hydroxyl groups of the organopolysiloxane resin as a component is 0% by mass or more and 1.0% by mass or less.
3. 3.
(A1) The method for producing a cationically polymerizable organopolysiloxane according to 1, wherein the total content of hydroxyl groups of the organopolysiloxane resin as a component is 0% by mass or more and 0.8% by mass or less.
4.
(A1) The method for producing a cationically polymerizable organopolysiloxane according to 1, wherein the total content of hydroxyl groups of the organopolysiloxane resin as a component is 0% by mass or more and 0.6% by mass or less.
5.
The method for producing a cationically polymerizable organopolysiloxane according to 1, wherein the boiling point of the cyano group-containing organic compound of the component (a3) is 300 ° C. or lower under normal pressure.
6.
A heavy release additive for a release sheet made of a cationically polymerizable organopolysiloxane obtained by the production method according to any one of 1 to 5.
7.
A peelable radiation-curable silicone composition containing a cationically polymerizable organopolysiloxane obtained by the production method according to any one of 1 to 5 as a heavy peeling additive.
8.
7. A method for producing a release sheet, wherein the releaseable radiation-curable silicone composition according to 7 is applied onto a substrate and cured by irradiation.
9.
A release sheet obtained by forming a cured film of the releaseable radiation-curable silicone composition according to 7 on a substrate.

The cationically polymerizable organopolysiloxane obtained by the production method of the present invention can suppress an increase in viscosity and gelation, and the cationically polymerizable organopolysiloxane can be used as a heavy release additive for a release sheet. The peeling sheet obtained by using the heavy peeling additive is heavier than the peeling sheet obtained by using the conventional heavy peeling additive, and the peeling force over time is stable.

The method for producing a cationically polymerizable organopolysiloxane of the present invention uses the components (a1) to (a4) described later, and the SiOH group in the component (a1) in the presence or absence of the component (a3). In the presence of the component (a3), the component (a4) is added to a condensate obtained by dehydrogenating the SiH group in the component (a2) or the following component (a1) and the component (a2). Then, the SiH group remaining in the condensate and / or the SiH group in the component (a2) and the alkenyl group in the component (a4) are subjected to an addition reaction.
In the present invention, the cationically polymerizable organopolysiloxane is not limited to the organopolysiloxane obtained by adding the component (a4) to the condensate of the component (a1) and the component (a2), and the component (a2) is (a4). It is defined as containing a mixture of the organopolysiloxane obtained by the addition reaction of the components and the component (a1).

Hereinafter, the method for producing the cationically polymerizable organopolysiloxane of the present invention will be described in detail.

The component (a1) is _{mainly composed of (SiO 4/2} ) unit (Q unit) and (R ¹ ₃ SiO _1/2 ) unit (M unit), and ^{(R 1} ₃ SiO) with respect _{to the (SiO 4/2) unit. 1/2} ) The unit ratio (M unit / Q unit) is 0.6 to 1.2 as a molar ratio, and the total content of hydroxyl groups bonded to silicon atoms is 0% by mass or more and 1.2% by mass or less. An organopolysiloxane resin.

In the formula, R ¹ is a monovalent hydrocarbon group having 1 to 12 carbon atoms having no hydroxyl group or aliphatic unsaturated bond, which is the same or different, and specifically, a hydroxyl group, a methyl group, an ethyl group, and a propyl group. An alkyl group such as a group, an isopropyl group, a butyl group or an isobutyl group, a cycloalkyl group such as a cyclohexyl group, an aryl group such as a phenyl group or a tolyl group, and one of the hydrogen atoms bonded to the carbon atom of these groups. Part or all of the halogen-substituted alkyl group such as 3,3,3-trifluoropropyl group, perfluorobutylethyl group, perfluorooctylethyl group substituted with halogen atom such as fluorine, chlorine, methoxy substituted with alkoxy group. Examples thereof include monovalent hydrocarbon groups having 1 to 12 carbon atoms, preferably 1 to 8 carbon atoms, which do not have an unsubstituted or substituted aliphatic unsaturated bond, such as an alkoxy-substituted alkyl group such as a propyl group or an ethoxypropyl group. Be done. As R ¹ , a hydroxyl group, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group and an isobutyl group are preferable.

In the organopolysiloxane resin, the ratio of M units to Q units (M units / Q units) is 0.6 to 1.2, preferably 0.65 to 1.1, and more preferably 0.65 to 1.1 as a molar ratio. It is 0.7 to 1.0. If the ratio of M units to Q units is less than 0.6, the viscosity of the reaction product becomes too high and synthesis becomes difficult. If it exceeds 1.2, the degree of polymerization cannot be increased, so that the heavy peeling effect is also reduced.

The organopolysiloxane resin may contain R ¹ ₂ SiO _2/2 units (D units) and R ¹ SiO _3/2 units (T units) (R ¹ is the same as above), if necessary. However, the composition of these D units and T units is preferably 20 mol% or less, particularly preferably 10 mol% or less.

In the organopolysiloxane resin, the total content of the hydroxyl groups bonded to the silicon atom is 0% by mass or more and 1.2% by mass or less, preferably 0% by mass or more and 1.0% by mass or less, and more preferably 0. It is mass% or more and 0.8 mass% or less, and more preferably 0 mass% or more and 0.6 mass% or less.
The hydroxyl groups are mixed from the raw material for producing the organopolysiloxane resin, and the mixing is usually unavoidable. However, the smaller the amount of hydroxyl groups in the organopolysiloxane resin, the more the book. It was found that the cationically polymerizable organopolysiloxane produced by the production method is effective as a heavy peeling additive. That is, the amount of hydroxyl groups in the organopolysiloxane resin is most preferably 0% by mass as the heavy peeling additive. Further, if the total content of the hydroxyl groups exceeds 1.2% by mass, the heavy peeling ability is lowered when the heavy peeling additive is used. However, when a hydroxyl group is contained, it is preferably 0.001% by mass or more.

（式中、Ｒ²は同一もしくは異種の、水素原子又は炭素数１〜１０の１価炭化水素基であり、Ｒ²のうち少なくとも１個は水素原子を含む。Ｒ³は同一もしくは異種の、炭素数１〜１０の１価炭化水素基である。ａ≧２、ｂ≧０、ｃ≧０、ｄ≧０、２≦ａ＋ｂ＋ｃ＋ｄ≦３，０００である。またｅ≧１、ｆ≧０、ｅ＋ｆ≧３である。）The organohydrogen (poly) siloxane as the component (a2) is represented by the following average composition formulas (1) and / or (2).

(In the formula, R ² is the same or dissimilar hydrogen atom or monovalent hydrocarbon group having 1 to 10 carbon atoms, and ^{at least one of R 2} contains a hydrogen atom. R ³ is the same or dissimilar. It is a monovalent hydrocarbon group having 1 to 10 carbon atoms. A ≧ 2, b ≧ 0, c ≧ 0, d ≧ 0, 2 ≦ a + b + c + d ≦ 3,000. Also, e ≧ 1, f ≧ 0, e + f. ≧ 3)

In the above formulas (1) and (2), R ² is the same or different hydrogen atom or monovalent hydrocarbon group having 1 to 10 carbon atoms, and R ³ is the same or different carbon atoms and has 1 to 10 carbon atoms. It is a monovalent hydrocarbon group. Specific examples of the monovalent hydrocarbon group having 1 to 10 carbon atoms include an alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group and an isobutyl group, a cycloalkyl group such as a cyclohexyl group, and a phenyl group. Aryl groups such as groups and trill groups, and some or all of the hydrogen atoms bonded to the carbon atoms of these groups are replaced with halogen atoms such as fluorine and chlorine 3,3,3-trifluoropropyl. An unsubstituted or substituted carbon number 1 to 1, such as a halogen-substituted alkyl group such as a group, a perfluorobutylethyl group or a perfluorooctylethyl group, an alkoxy-substituted alkyl group substituted with an alkoxy group, or an alkoxy-substituted alkyl group such as an ethoxypropyl group. 10, preferably, a monovalent hydrocarbon group having 1 to 8 carbon atoms can be mentioned. As R ² , a hydrogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group and an isobutyl group are preferable, and as R ³ , a methyl group, an ethyl group, a propyl group and an isopropyl group are preferable. It should be noted that at least one, preferably 2 to 50, of R ^{2 contains a hydrogen atom.}

The a, b, c, and d in the average composition formula (1) are a ≧ 2, b ≧ 0, c ≧ 0, d ≧ 0, 2 ≦ a + b + c + d ≦ 3,000, and preferably 2 ≦ a ≦ 4. , 0 ≦ b ≦ 1,000, 0 ≦ c ≦ 1, 0 ≦ d ≦ 1, 2 ≦ a + b + c + d ≦ 1,002.
Further, e and f in the average composition formula (2) are e ≧ 1, f ≧ 0, and e + f ≧ 3, preferably 1 ≦ e ≦ 15, 0 ≦ f ≦ 10, and 3 ≦ e + f ≦ 25. ..
The a, b, c, d, e, and f in the average composition formula (1) and / or the average composition formula (2) preferably have an organohydrogen (poly) siloxane having a viscosity of 1 to 20,000 mPa at 25 ° C. -S, more preferably a number having a viscosity of 5 to 10,000 mPa · s. The viscosity is a value measured by a BM type rotational viscometer.

Further, in the above-mentioned organohydrogen (poly) siloxane, the silicon atom substituted with a hydrogen atom is preferably 2 to 100 mol%, preferably 2 to 70 mol% of the total silicon atom in the total siloxane unit. .. In the average composition formula (1), the hydrogen atom bonded to the silicon atom is bonded to both the terminal of the molecular chain and the middle of the molecular chain (side chain). May be good.

The SiOH group in the hydroxyl group-containing organopolysiloxane resin (a1) and the SiH group in the organohydrogen (poly) siloxane (a2) are subjected to a dehydrogenation condensation reaction. When the component (a1) does not contain a SiOH group (that is, when the total content of the SiOH groups is 0% by mass), the dehydration condensation reaction is not necessary, so the component (a1) and the component (a2) are mixed. All you have to do is.
At this time, the ratio of the organopolysiloxane resin (a1) to the organohydrogen (poly) siloxane (a2) is the mass ratio (a1) of the organopolysiloxane resin (a1) to the organohydrogen (poly) siloxane (a2). / (A2) is preferably 1/99 to 95/5, more preferably 2/98 to 90/10, and even more preferably 5/95 to 80/20. If the proportion of the organopolysiloxane resin (a1) is less than 1/99, the heavy peeling ability may be insufficient when the cationically polymerizable organopolysiloxane of the present invention is used as the heavy peeling additive, which is 95/5. If it is more than that, the curability and the residual adhesion rate may decrease.

When the component (a1) contains a SiOH group, the molar ratio of the SiH group of the organohydrogen (poly) siloxane (a2) to the hydroxyl group of the organopolysiloxane resin (a1) containing a hydroxyl group ((a2) SiH group). / (A1) OH group) is preferably 2 or more and 10,000 or less, more preferably 4 or more and 8,000 or less, and further preferably 5 or more and 6,000 or less. If the molar ratio is less than 2, a large amount of SiH groups are consumed by the condensation reaction, so that the amount of epoxy groups of the cationically polymerizable organopolysiloxane obtained by the addition reaction after the condensation reaction is reduced, and the cationically polymerizable property is lowered. It may end up.

A dehydrogenation condensation catalyst is used for the dehydrogenation condensation reaction between the component (a1) and the component (a2). Examples of this catalyst include chloroplatinic acid, an alcohol solution of chloroplatinic acid, a reaction product of chloroplatinic acid and alcohol, a reaction product of chloroplatinic acid and an olefin compound, and a reaction product of chloroplatinic acid and a vinyl group-containing siloxane. Platinum-based catalyst can be mentioned.
The amount of these catalysts added is not particularly limited, but is preferably 0.01 to 5% by mass of the total mass of the hydroxyl group-containing organopolysiloxane resin (a1) and the organohydrogen (poly) siloxane (a2). , More preferably 0.02 to 4% by mass, still more preferably 0.05 to 3% by mass.

The dehydrogenation condensation reaction between the component (a1) and the component (a2) is carried out in a solvent, if necessary. Examples of the solvent include aromatic solvents such as toluene and xylene, aliphatic solvents such as hexane and octane, ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone, ester solvents such as ethyl acetate and isobutyl acetate, or a mixture thereof. Solvents can be used.

The dehydrogenation condensation reaction between the components (a1) and (a2) may usually be carried out at 20 to 300 ° C., but the reaction proceeds faster when heated to 40 ° C. or higher. The reaction time is not particularly limited, but is preferably 0.1 to 10 hours. The reaction atmosphere may be either air or an inert gas.

Next, the cyano group-containing organic compound (a3) is added to the condensate obtained above or the mixture of the above (a1) component and (a2) component, and then the alkenyl group-containing epoxy compound (a4) is blended. The SiH group remaining in the condensate and / or the SiH group in the component (a2) above is subjected to an addition reaction with the alkenyl group in the alkenyl group-containing epoxy compound (a4).
Since the component (a3) is not involved in the condensation reaction, it may be added before the component (a1) and the component (a2) are condensed, or after the condensation reaction between the component (a1) and the component (a2). However, it is preferable to add the component (a3) after the condensation reaction between the component (a1) and the component (a2).

The cyano group-containing organic compound as the component (a3) is represented by the following general formula (3).
R ^4- CN (3)
(In the formula, R ⁴ is a monovalent hydrocarbon group having 1 to 15 carbon atoms having no aliphatic unsaturated bond.)

In the above formula (3), R ⁴ is a monovalent hydrocarbon group having 1 to 15 carbon atoms having no aliphatic unsaturated bond, and specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, and the like. Alkyl groups such as butyl groups, cycloalkyl groups such as cyclohexyl groups, aryl groups such as phenyl groups, tolyl groups, and naphthyl groups, or some or all of the hydrogen atoms bonded to the carbon atoms of these groups are cyano. Unsubstituted or substituted carbon numbers 1 to 15, which do not have an aliphatic unsaturated bond, such as a cyanoethyl group, a 3-chloropropyl group, a 3,3,3-trifluoropropyl group substituted with a group or a halogen atom, It is preferably a monovalent hydrocarbon group having 1 to 8 carbon atoms. As R ⁴ , a methyl group, an ethyl group, a propyl group, an isopropyl group, a phenyl group and a naphthyl group are preferable.

The cationically polymerizable organopolysiloxane obtained after the addition reaction described later can be solvent-free, in which case the cyano group-containing organic compound needs to be removed from the reaction mixture. In this case, a method of distilling off the solvent or a low boiling point substance used under heating and reduced pressure can be used. Therefore, when the boiling point of the cyano group-containing organic compound under normal pressure is preferably 300 ° C. or lower, more preferably 250 ° C. or lower, distillation after the addition reaction is easy.

The amount of the cyano group-containing organic compound used is 10 mass ppm or more, preferably 100 mass ppm or more, and more preferably 200 mass ppm or more of the alkenyl group-containing epoxy compound (a4) described later. The upper limit is not particularly limited, but is usually preferably 10% by mass or less.

Examples of the alkenyl group-containing epoxy compound as the component (a4) include compounds represented by the following formulas (a4-1) to (a4-7), preferably the following formulas (a4-1) and (a4). -2), (a4-4), (a4-6) or (a4-7), more preferably the following formula (a4-1), (a4-6) or (a4-7). It is a compound indicated by.

A condensate obtained by dehydrocondensing the hydroxyl group-containing organopolysiloxane resin (a1) and the organohydrogen (poly) siloxane (a2) in the present invention and / or the organohydrogen (poly) siloxane (a2) and an alkenyl group. The ratio of the contained epoxy compound (a4) to be used is such that the number of alkenyl groups in the alkenyl group-containing epoxy compound is larger than the total number of SiH groups remaining in the condensate and / or SiH groups in the component (a2). The molar ratio of the alkenyl group / SiH group is 1.0 or more and 2.0 or less, preferably 1.05 or more and 1.8 or less, and more preferably 1.1 or more and 1.5 or less. Is desirable. If the molar ratio is too small, the addition reaction may not proceed completely, and if it is too large, the addition reaction rate may not be expected to be improved.

The addition reaction is carried out using an addition reaction catalyst having a catalytic amount, but if a platinum-based catalyst as a dehydrogenation condensation catalyst exists, it is not necessary to add a new addition reaction catalyst, and the dehydrogenation condensation reaction is carried out. It is convenient because the following addition reaction can be carried out by adding the cyano group-containing organic compound (a3) and the alkenyl group-containing epoxy compound (a4) to the reaction vessel.
Examples of the addition reaction catalyst include the platinum-based catalyst described above. The amount of the catalyst used in this addition reaction may be an effective amount, but platinum is based on the total mass of the condensate and / or the component (a2) and the component (a4) obtained above. In terms of mass of group metal, it is preferably 0.01 to 100 ppm, more preferably 0.1 to 50 ppm, and further preferably 0.5 to 20 ppm.

The addition reaction is carried out in the solvent used in the above-mentioned dehydrogenation condensation reaction, if necessary.
This addition reaction may usually be carried out at 20 to 300 ° C., but the reaction proceeds faster when heated to 40 ° C. or higher. The reaction time is not particularly limited, but 10 minutes to 24 hours is preferable. The reaction atmosphere may be either air or an inert gas.

After the addition reaction is completed, the addition reaction catalyst can be removed by washing the reaction mixture with water or treating with activated carbon, if necessary. When a solvent is used, it can be distilled off under heating and reduced pressure at, for example, 50 to 200 ° C., 5 to 50 mmHg, for 1 to 24 hours to obtain a solvent-free cationically polymerizable organopolysiloxane.

The viscosity of the cationically polymerizable organopolysiloxane thus obtained at 25 ° C. is preferably 50 to 20,000 mPa · s, particularly preferably 100 to 15,000 mPa · s.

The amount of the epoxy group of the cationically polymerizable organopolysiloxane obtained in the present invention is such that the proportion of silicon atoms to which the epoxy group-containing organic group is bonded is 1 to 40 mol%, preferably 3 to 30 mol%, and further. It is preferably 5 to 25 mol%. If it is less than 1 mol%, the curability and the residual adhesion rate may decrease. If it exceeds 40 mol%, it may be peeled more than necessary, and peeling from the adhesive substance may not be possible. Since the epoxy group amount is indicated by the ratio of silicon atoms to which the epoxy group-containing organic group is bonded as described above, it can be determined from the chemical structural formula, and when measuring the epoxy group amount, the epoxy equivalent (g / g /). The measurement of mol) is simple. For example, the Hiranuma automatic adjusting device COM-1750S manufactured by Hiranuma Sangyo Co., Ltd. is effective for measuring the epoxy equivalent. In this case, the epoxy equivalent of the obtained cationically polymerizable organopolysiloxane is preferably 500 to 3,000 g / mol.

The cationically polymerizable organopolysiloxane obtained by the production method of the present invention can be suitably used as a heavy peeling additive for a release sheet, and the cationically polymerizable organopolysiloxane of the present invention can be peeled off by itself or with this. A dissimilar cationically polymerizable organopolysiloxane is mixed for the purpose of adjusting the force, and a photoacid generator is further added to obtain a peelable radiation-curable silicone composition.

In this case, the heterogeneous cationically polymerizable organopolysiloxane may be any cationically polymerizable organopolysiloxane containing no resin component, but is preferably known as described in Japanese Patent No. 3384268 and JP-A-2015-168721. Cationic polymerizable organopolysiloxane and the like can be used.
The amount of the different types of cationically polymerizable organopolysiloxane used is not particularly limited, but may be, for example, 0 to 99 parts by mass, particularly 5 to 95 parts by mass, based on 100 parts by mass of the cationically polymerizable organopolysiloxane of the present invention. preferable.

Further, as the photoacid generator, a known onium salt-based photoacid generator described in Japanese Patent No. 6195413 can be used, and for example, diaryliodonium hexafluorohexafluoroantimonate, bis- [4-nalkyl ( C10-C13) Phenyl] Iodonium Hexafluoroantimonate, 4- (isopropyl) phenyl (p-tolyl) iodonium tris (pentafluoroethyl) trifluorophosphate, (4-methylphenyl) (4-isopropylphenyl) iodonium tetrakis (penta) Examples thereof include fluorphenyl) borate and bis- [4-n alkyl (C10 to C13) phenyl] iodonium tetrakis (pentafluorphenyl) borate.
The amount of the photoacid generator used is also not particularly limited. For example, 0.1 to 100 parts by mass of the cationically polymerizable organopolysiloxane of the present invention or a cationically polymerizable organopolysiloxane of a different type thereof. It is preferably 10 parts by mass, particularly 0.2 to 8 parts by mass.

In addition, the peelable radiation-curable silicone composition has, as optional components, an epoxy-based diluent, a vinyl ether-based diluent, an adhesion improver to a substrate, other types of organopolysiloxane, a leveling agent, a filler, and an antistatic agent. Agents, flame retardants, defoamers, pigments, flow modifiers, light stabilizers, non-reactive resins and the like may be added, or diluted with an organic solvent before use. The amount of the optional component added can be a normal amount as long as the effect of the present invention is not impaired.

Here, when the cause of the heavy peeling effect being stronger than that of the conventional heavy peeling additive when the cationically polymerizable organopolysiloxane of the present invention is used as the heavy peeling additive for the release sheet, usually, the cationically polymerizable organopoly is usually used. In siloxane, cationic polymerization proceeds by ring-opening polymerization of epoxy groups to impart peelability to the formed film, but organopolysiloxane resin becomes a heavy peeling component, and the abundance of organopolysiloxane resin on the cured film. The greater the amount, the more the cured film becomes a heavy peeling.
On the other hand, in the ring-opening polymerization of the epoxy group, a compound having active hydrogen can also participate in the reaction, but when a large amount of SiOH groups are contained in the organopolysiloxane resin, these are involved in the ring-opening polymerization of the epoxy group and are cured. Since the organopolysiloxane resin is incorporated into the film, the organopolysiloxane resin cannot be deposited on the surface of the film, and the heavy peeling effect is reduced.

Since the amount of SiOH in the organopolysiloxane resin used in the production method of the present invention is as small as 0% by mass to 1.2% by mass, the organopolysiloxane resin is incorporated into the film formed by ring-opening polymerization of epoxy groups. Since it is difficult, the heavy peeling is higher than that of the conventional heavy peeling additive of cationically polymerizable organopolysiloxane.

Further, the cationically polymerizable organopolysiloxane in which the polymerization reaction by opening the ring of the epoxy group proceeds due to the side reaction generated during the addition reaction of the organohydrogen (poly) siloxane and the alkenyl group-containing epoxy compound increases in viscosity and gels. However, the release sheet prepared by curing the releaseable radiation-curable silicone composition containing the cationically polymerizable organopolysiloxane containing these by-products has a transfer amount because the ring-opened epoxy group cannot participate in the cationic polymerization. It rises and becomes light peeling.

In the method for producing a cationically polymerizable organopolysiloxane of the present invention, the presence of the cyano group-containing organic compound during the addition reaction can suppress the polymerization reaction due to the ring opening of the epoxy group during the above-mentioned addition reaction, and thus the ring is opened. There is no increase in the amount of migration due to the epoxy group, and there is no effect of light peeling due to this.
Therefore, it is considered that the cationically polymerizable organopolysiloxane produced by the above-mentioned production method of the present invention has a stronger heavy peeling effect than the conventional heavy peeling additive when used as a heavy peeling additive for a release sheet.

The peelable radiation-curable silicone composition is applied onto various base materials and cured by irradiation to form a cured film having peelability, thereby obtaining a peelable sheet having the peelability imparted to the base material. Can be done.
The base material is not particularly limited, and various commonly used base materials can be used. For example, glassin paper, clay coat paper, high-quality paper, polyethylene laminated paper, polyester film, polystyrene film, polyethylene film, etc. Examples thereof include plastic films such as polypropylene films, transparent resins such as polycarbonate, and metal foils such as aluminum foil.

Further, as a coating method of the peelable radiation curable silicone composition, known methods such as roll coating, gravure coating, wire doctor coating, air knife coating, and dipping coating can be used.
The amount of the peelable radiation-curable silicone composition applied is not particularly limited, but is usually about ^{0.05 to 3 g / m 2.}

When the peelable radiation-curable silicone composition is cured by irradiation, the radiation energy rays are preferably high-pressure or ultra-high pressure mercury lamp, metal halide lamp, xenon lamp, carbon arclamp, fluorescent lamp, semiconductor solid-state laser, argon. Energy rays in the ultraviolet to visible light region (about 100 to about 800 nm) obtained from a laser, a He-Cd laser, a KrF excimer laser, an ArF excimer laser, an F _{2 laser, or the like are used.} A radiation light source having a strong light intensity of 200 to 400 nm is preferable. Further, radiation having high energy such as electron beam and X-ray can be used. The irradiation time of radiation energy is usually about 0.1 to 10 seconds at room temperature (25 ° C.), but when the energy ray permeability is low or the film thickness of the peelable radiation-curable silicone composition is high. If it is thick, it may be preferable to spend more time. If necessary, after irradiation with energy rays, it is possible to heat at room temperature (25 ° C.) to 150 ° C. for several seconds to several hours for aftercure.

Hereinafter, the present invention will be specifically described with reference to Synthesis Examples, Examples and Comparative Examples, but the present invention is not limited thereto. Further, in the following example, the physical properties in the table are measured by the following test method. The viscosity is a value measured at 25 ° C. with a BM type rotational viscometer, and the epoxy equivalent is a value measured with a Hiranuma automatic qualifier COM-1750S manufactured by Hiranuma Sangyo Co., Ltd. In the structural formula, Me represents a methyl group and Ep represents the following epoxy functional group.

[Synthesis Example 1]
A 500 mL three-necked flask equipped with a stirrer, a thermometer, and a reflux condenser, which corresponds to (a1) of the component of the present invention, has (SiO _4/2 ) units, (Me ₃ SiO _1/2 ) units, and ( A 60% by mass toluene solution (M unit / Q unit (M / Q) = 0.70) of an organopolysiloxane resin (a1-1) consisting of HOSiO _{3/2) units and having a hydroxyl group content of 1.10% by mass.} 224.0 g, which corresponds to (a2) of the component of the present invention, was represented by the following average composition formula (a2-1), and 157.7 g of organohydrogenpolysiloxane having a viscosity at 25 ° C. of 5 mPa · s was added. To this, 0.85 g of a toluene solution of Krastedt having a platinum concentration of 0.5% by mass was added, refluxed at 130 ° C. for 4 hours, a dehydrogenation condensation reaction was carried out, and then the mixture was allowed to cool to 50 ° C.
Here, after adding 0.59 g of acetonitrile (a3-1) corresponding to the component (a3) of the present invention, 1,2-epoxy-4-vinylcyclohexane (a4-1) corresponding to the component (a4) of the present invention is added. ) 64.75 g was added dropwise with a dropping funnel over 1 hour, and after completion of the addition, the mixture was heated and stirred at 70 ° C. for 1 hour. The reaction mixture was distilled off under reduced pressure at 100 ° C. and 20 mmHg for 3 hours to obtain a cationically polymerizable organopolysiloxane (A1-1) having an average epoxy equivalent of 900 g / mol and a viscosity at 25 ° C. of 390 mPa · s. ..

[Synthesis Example 2]
Organopoly corresponding to (a1) of the component of the present invention, _{consisting of (SiO 4/2} ) unit, (Me ₃ SiO _1/2 ) unit and (HOSiO _3/2 ) unit, and having a hydroxyl group content of 0.75% by mass. By performing the same procedure as in Synthesis Example 1 except that 224.0 g of a 60 mass% toluene solution (M / Q = 0.70) of the siloxane resin (a1-2) was used, the average epoxy equivalent was 900 g / g. A cationically polymerizable organopolysiloxane (A1-2) having a viscosity of 400 mPa · s at mol and 25 ° C. was obtained.

[Synthesis Example 3]
Organopoly corresponding to (a1) of the component of the present invention, _{consisting of (SiO 4/2} ) unit, (Me ₃ SiO _1/2 ) unit and (HOSiO _3/2 ) unit, and having a hydroxyl group content of 0.34% by mass. By performing the same procedure as in Synthesis Example 1 except that 224.0 g of a 60 mass% toluene solution (M / Q = 0.70) of the siloxane resin (a1-3) was used, the average epoxy equivalent was 890 g / g. A cationically polymerizable organopolysiloxane (A1-3) having a viscosity of 380 mPa · s at mol and 25 ° C. was obtained.

[Synthesis Example 4]
Organopoly corresponding to (a1) of the component of the present invention, _{consisting of (SiO 4/2} ) unit, (Me ₃ SiO _1/2 ) unit and (HOSiO _3/2 ) unit, and having a hydroxyl group content of 0.20% by mass. By performing the same procedure as in Synthesis Example 1 except that 224.0 g of a 60 mass% toluene solution (M / Q = 0.70) of the siloxane resin (a1-4) was used, the average epoxy equivalent was 900 g / g. A cationically polymerizable organopolysiloxane (A1-4) having a viscosity of 370 mPa · s at mol and 25 ° C. was obtained.

[Synthesis Example 5]
Organopoly corresponding to (a1) of the component of the present invention, _{consisting of (SiO 4/2} ) unit, (Me ₃ SiO _1/2 ) unit and (HOSiO _3/2 ) unit, and having a hydroxyl group content of 0.10% by mass. By performing the same procedure as in Synthesis Example 1 except that 224.0 g of a 60 mass% toluene solution (M / Q = 0.70) of the siloxane resin (a1-5) was used, the average epoxy equivalent was 880 g /. A cationically polymerizable organopolysiloxane (A1-5) having a viscosity of 350 mPa · s at mol and 25 ° C. was obtained.

[Synthesis Example 6]
Organopoly corresponding to (a1) of the component of the present invention, _{consisting of (SiO 4/2} ) unit, (Me ₃ SiO _1/2 ) unit and (HOSiO _3/2 ) unit, and having a hydroxyl group content of 0.005% by mass. By performing the same procedure as in Synthesis Example 1 except that 224.0 g of a 60 mass% toluene solution (M / Q = 0.70) of the siloxane resin (a1-6) was used, the average epoxy equivalent was 880 g /. A cationically polymerizable organopolysiloxane (A1-6) having a viscosity of 330 mPa · s at mol and 25 ° C. was obtained.

[Synthesis Example 7]
Organopoly corresponding to (a1) of the component of the present invention, _{consisting of (SiO 4/2} ) unit, (Me ₃ SiO _1/2 ) unit and (HOSiO _3/2 ) unit, and having a hydroxyl group content of 1.10% by mass. By performing the same procedure as in Synthesis Example 1 except that 224.0 g of a 60 mass% toluene solution (M / Q = 1.10) of the siloxane resin (a1-7) was used, the average epoxy equivalent was 900 g / g. A cationically polymerizable organopolysiloxane (A1-7) having a viscosity of 350 mPa · s at mol and 25 ° C. was obtained.

[Comparative Synthesis Example 1]
By carrying out the same procedure as in Synthesis Example 1 except that acetonitrile (a3-1) was not used, a cationically polymerizable organopolysiloxane (X1-1) having a viscosity at 25 ° C. of 800 mPa · s was obtained.

[Comparative synthesis example 2]
By carrying out the same procedure as in Synthesis Example 2 except that acetonitrile (a3-1) was not used, a cationically polymerizable organopolysiloxane (X1-2) having a viscosity at 25 ° C. of 780 mPa · s was obtained.

[Comparative Synthesis Example 3]
By carrying out the same procedure as in Synthesis Example 3 except that acetonitrile (a3-1) was not used, a cationically polymerizable organopolysiloxane (X1-3) having a viscosity at 25 ° C. of 770 mPa · s was obtained.

[Comparative Synthesis Example 4]
60% by mass of organopolysiloxane resin (a1-8) consisting of (SiO _4/2 ) unit, (Me ₃ SiO _1/2 ) unit and (HOSiO _3/2 ) unit and having a hydroxyl group content of 1.30% by mass. By carrying out the same procedure as in Synthesis Example 1 except that 224.0 g of a toluene solution (M / Q = 0.70) and acetonitrile (a3-1) are not used, a cation having a viscosity at 25 ° C. of 850 mPa · s. A polymerizable organopolysiloxane (X1-4) was obtained.

Table 1 shows the results of Synthesis Examples 1 to 7 and Comparative Synthesis Examples 1 to 4.
The cationically polymerizable organopolysiloxanes of Synthesis Examples 1 to 7 obtained by the production method of the present invention had a low viscosity without gelation.
The cationically polymerizable organopolysiloxanes of Comparative Synthesis Examples 1 to 4 have a higher viscosity than the cationically polymerizable organopolysiloxanes of the above synthesis examples, although the cyano group-containing organic compound is not added during the addition reaction. ..

Next, a peelable radiation-curable silicone composition using the cationically polymerizable organopolysiloxane obtained above as a heavy peeling additive was prepared, and the peeling characteristics were measured by the following method in order to evaluate the cured film. ..

[Peeling force test of peelable radiation-curable silicone composition]
A peelable radiation-curable silicone composition containing a heavy peeling additive was prepared, and then rolled and applied to PE laminated paper at ^{a coating amount of about 0.8 g / m 2} to obtain a coating film. The obtained coating film was irradiated with ultraviolet rays at an irradiation amount of ^{75 mJ / cm 2} using two 80 W / cm high-pressure mercury lamps to form a cured film. A polyester adhesive tape TESA-7475 (manufactured by tesa, acrylic adhesive) having a width of 25 mm was attached to the surface of the cured film, and a 2 kg roller was reciprocated once and crimped to prepare a sample for measuring the peeling force.
The sample was aged at 25 ° C. for 20-24 hours under a load ^{of 70 g / cm 2.} Then, using a tensile tester, the bonded polyester adhesive tape was pulled at a peeling speed of 0.3 m / min at an angle of 180 °, and the force (N / 25 mm) required for peeling was measured. The results are shown in Table 2.

[Measurement test of residual adhesion rate of peelable radiation curable silicone composition]
A peelable radiation-curable silicone composition containing a heavy peeling additive was prepared, and then rolled and applied to PE laminated paper at ^{a coating amount of about 0.8 g / m 2} to obtain a coating film. The obtained coating film was irradiated with ultraviolet rays at an irradiation amount of ^{75 mJ / cm 2} using two 80 W / cm high-pressure mercury lamps to form a cured film. A polyester adhesive tape TESA-7475 (manufactured by tesa, acrylic adhesive) having a width of 25 mm was attached to the surface of the cured film, and a 2 kg roller was reciprocated once and crimped to prepare a sample for measuring the peeling force.
The sample was aged at 25 ° C. for 20-24 hours under a load ^{of 70 g / cm 2.} Then, the bonded polyester adhesive tape was peeled off at a peeling speed of 0.3 m / min at an angle of 180 ° using a tensile tester, and the polyester adhesive tape was stuck on the SUS plate. The force (Y) required to peel off the polyester adhesive tape was measured after the 2 kg roller was reciprocated once and crimped and left at 25 ° C. for 30 minutes. The force (Z) required to peel the sample polyester adhesive tape, which was not attached to the cured film but attached to the SUS plate and subjected to the same treatment, from the SUS plate was measured, and (Y) was determined. The value divided by (Z) is taken as the residual adhesion ratio, and the results are shown in Table 2.

[Example 1]
Synthesis This is a mixture of 50 parts by mass of the cationically polymerizable organopolysiloxane (A1-1) synthesized in Example 1 and the compounds represented by the following average composition formulas (aa) and (ab) as a release modifier. 50 parts by mass of cationically polymerizable organopolysiloxane (Y-1) having an average epoxy equivalent of 1,100 g / mol and a viscosity at 25 ° C. of 150 mPa · s, 50 parts by mass of a photoacid generator, and 50 parts by mass of isopropyl alcohol. 2.0 parts by mass of a% dissolved bis- [4-n alkyl (C10-C13) phenyl] iodonium hexafluoroantimonate solution (Z-1) was uniformly mixed to obtain a silicone composition 1. This silicone composition 1 was cured by the above method, and the peeling force and the residual adhesive rate were measured.

[Example 2]
Synthesis The silicone composition 2 was obtained by performing the same procedure as in Example 1 except that the cationically polymerizable organopolysiloxane (A1-2) synthesized in Example 2 was made up to 50 parts by mass. This silicone composition 2 was cured by the above method, and the peeling force and the residual adhesive ratio were measured.

[Example 3]
Synthesis The silicone composition 3 was obtained by performing the same procedure as in Example 1 except that the cationically polymerizable organopolysiloxane (A1-3) synthesized in Example 3 was made up to 50 parts by mass. This silicone composition 3 was cured by the above method, and the peeling force and the residual adhesive ratio were measured.

[Example 4]
Synthesis The silicone composition 4 was obtained by performing the same procedure as in Example 1 except that the cationically polymerizable organopolysiloxane (A1-4) synthesized in Example 4 was made up to 50 parts by mass. This silicone composition 4 was cured by the above method, and the peeling force and the residual adhesive ratio were measured.

[Example 5]
Synthesis The silicone composition 5 was obtained by performing the same procedure as in Example 1 except that the cationically polymerizable organopolysiloxane (A1-5) synthesized in Example 5 was made up to 50 parts by mass. This silicone composition 5 was cured by the above method, and the peeling force and the residual adhesive ratio were measured.

[Example 6]
Synthesis The silicone composition 6 was obtained by performing the same procedure as in Example 1 except that the cationically polymerizable organopolysiloxane (A1-6) synthesized in Example 6 was made up to 50 parts by mass. This silicone composition 6 was cured by the above method, and the peeling force and the residual adhesive ratio were measured.

[Example 7]
Synthesis The silicone composition 7 was obtained by performing the same procedure as in Example 1 except that the cationically polymerizable organopolysiloxane (A1-7) synthesized in Example 7 was made up to 50 parts by mass. This silicone composition 7 was cured by the above method, and the peeling force and the residual adhesive ratio were measured.

[Example 8]
By performing the same procedure as in Example 1 except that the cationically polymerizable organopolysiloxane (A1-1) of Example 1 was 75 parts by mass and the cationically polymerizable organopolysiloxane (Y-1) was 25 parts by mass. , Silicone composition 8 was obtained. This silicone composition 8 was cured by the above method, and the peeling force and the residual adhesive ratio were measured.

[Example 9]
By performing the same procedure as in Example 7 except that the cationically polymerizable organopolysiloxane (A1-7) of Example 7 was 75 parts by mass and the cationically polymerizable organopolysiloxane (Y-1) was 25 parts by mass. , Silicone composition 9 was obtained. This silicone composition 9 was cured by the above method, and the peeling force and the residual adhesive ratio were measured.

[Comparative Example 1]
The silicone composition 10 was obtained by performing the same procedure as in Example 1 except that the cationically polymerizable organopolysiloxane (X1-1) synthesized in Comparative Synthesis Example 1 was 50 parts by mass. The silicone composition 10 was cured by the above method, and the peeling force and the residual adhesive ratio were measured.

[Comparative Example 2]
The silicone composition 11 was obtained by performing the same procedure as in Example 1 except that the cationically polymerizable organopolysiloxane (X1-2) synthesized in Comparative Synthesis Example 2 was 50 parts by mass. The silicone composition 11 was cured by the above method, and the peeling force and the residual adhesive ratio were measured.

[Comparative Example 3]
The silicone composition 12 was obtained by performing the same procedure as in Example 1 except that the cationically polymerizable organopolysiloxane (X1-3) synthesized in Comparative Synthesis Example 3 was 50 parts by mass. The silicone composition 12 was cured by the above method, and the peeling force and the residual adhesive ratio were measured.

[Comparative Example 4]
The silicone composition 13 was obtained by performing the same procedure as in Example 1 except that the cationically polymerizable organopolysiloxane (X1-4) synthesized in Comparative Synthesis Example 4 was made up to 50 parts by mass. The silicone composition 13 was cured by the above method, and the peeling force and the residual adhesive ratio were measured.

[Comparative Example 5]
By performing the same procedure as in Comparative Example 1 except that the cationically polymerizable organopolysiloxane (X1-1) of Comparative Example 1 was 75 parts by mass and the cationically polymerizable organopolysiloxane (Y-1) was 25 parts by mass. , A silicone composition 14 was obtained. The silicone composition 14 was cured by the above method, and the peeling force and the residual adhesive ratio were measured.

Claims (9)

A condensate obtained by dehydrocondensing the following component (a1) and (a2) in the presence or absence of the following component (a3), or a mixture of the following component (a1) and component (a2). In the presence of the following component (a3), the following component (a4) is blended with the SiH group remaining in the condensate of the component (a1) and the component (a2) and / or the SiH group in the component (a2). (A4) A method for producing a cationically polymerizable organopolysiloxane, which comprises an addition reaction with an alkenyl group in a component.
(A1) (SiO _4/2 ) unit and (R ¹ ₃ SiO _1/2 ) unit (In the formula, R ¹ is the same or different, and has 1 to 12 carbon atoms that do not have a hydroxyl group or an aliphatic unsaturated bond. monovalent hydrocarbon group.) as a main component, (a 0.6 to 1.2 ratio of ^{_{SiO 4/2) (R 1 3 SiO}} 1/2 per unit) units as the molar ratio of hydroxyl group Organopolysiloxane resin with a total content of 0% by mass or more and 1.2% by mass or less,
(A2) Organohydrogen (poly) siloxane represented by the following average composition formulas (1) and / or (2),

(In the formula, R ² is the same or dissimilar hydrogen atom or monovalent hydrocarbon group having 1 to 10 carbon atoms, and ^{at least one of R 2} contains a hydrogen atom. R ³ is the same or dissimilar. It is a monovalent hydrocarbon group having 1 to 10 carbon atoms. A ≧ 2, b ≧ 0, c ≧ 0, d ≧ 0, 2 ≦ a + b + c + d ≦ 3,000. Also, e ≧ 1, f ≧ 0, e + f. ≧ 3)
(A3) A cyano group-containing organic compound represented by the following general formula (3),
R ^4- CN (3)
(In the formula, R ⁴ is a monovalent hydrocarbon group having 1 to 15 carbon atoms having no aliphatic unsaturated bond.)
(A4) Epoxy compound containing an alkenyl group. The method for producing a cationically polymerizable organopolysiloxane according to claim 1, wherein the total content of the hydroxyl groups of the organopolysiloxane resin as the component (a1) is 0% by mass or more and 1.0% by mass or less. The method for producing a cationically polymerizable organopolysiloxane according to claim 1, wherein the total content of the hydroxyl groups of the organopolysiloxane resin as the component (a1) is 0% by mass or more and 0.8% by mass or less. The method for producing a cationically polymerizable organopolysiloxane according to claim 1, wherein the total content of the hydroxyl groups of the organopolysiloxane resin as the component (a1) is 0% by mass or more and 0.6% by mass or less. The method for producing a cationically polymerizable organopolysiloxane according to claim 1, wherein the boiling point of the cyano group-containing organic compound of the component (a3) is 300 ° C. or lower under normal pressure. A heavy release additive for a release sheet made of a cationically polymerizable organopolysiloxane obtained by the production method according to any one of claims 1 to 5. A peelable radiation-curable silicone composition containing a cationically polymerizable organopolysiloxane obtained by the production method according to any one of claims 1 to 5 as a heavy peeling additive. A method for producing a release sheet, wherein the releaseable radiation-curable silicone composition according to claim 7 is applied onto a substrate and cured by irradiation. A release sheet obtained by forming a cured film of the releaseable radiation-curable silicone composition according to claim 7 on a substrate.