JP6809552B2 - Light peeling additive for radiation-curable release sheet, radiation-curable organopolysiloxane composition for release sheet, and release sheet - Google Patents

Description

The present invention is incorporated into a radiation-curable organopolysiloxane composition for a release sheet, which can reduce or need not add a radical polymerization initiator and can be a release sheet that is lightly peeled and odorless. The present invention relates to a light peeling additive for a radiation-curable release sheet, a radiation-curable organopolysiloxane composition for a release sheet containing the additive, a release sheet having a cured film of the composition, and a method for producing the same.

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, there are increasing applications for using a base material having poor heat resistance such as polyethylene terephthalate (PET) film for use in electronic members and optical materials.

Therefore, in recent years, a radiation curing method has been attracting attention as a method of giving curing energy other than heat without heating.
The curing method by radiation is radical polymerization using acrylic-modified polysiloxane, curing by en-thiol reaction using alkenyl-modified organopolysiloxane and mercapto-modified organopolysiloxane, and ring opening of epoxy-modified polysiloxane and acid epoxy group. Cationic polymerization and the like can be mentioned. Among them, radical polymerization using acrylic-modified polysiloxane inhibits curing due to the presence of oxygen. Therefore, although a device for lowering the oxygen concentration is required, it is extremely difficult. The greatest advantage is that it has good adhesion to the substrate. This makes it possible to develop back treatment agents for adhesive tapes, release papers for adhesive labels, tapes, etc., which are based on films with poor heat resistance that cause the base material to shrink due to heating, and the market will continue to expand in the future. Can be expected.

Many inventions have been proposed regarding a release agent for a radically polymerizable organopolysiloxane containing a (meth) acrylic group (Patent Document 1: Japanese Patent No. 2583677, Patent Document 2: Japanese Patent No. 2669947, Patent Document 3: Japanese Patent No. 3780113).

Further, in order to make the peelability of the cured film obtained by cross-linking the organopolysiloxane lightly peelable, it is common to add a light peeling additive.

According to Japanese Patent No. 2971357 (Patent Document 4), a hydroxyl group is bonded to silicon atoms at both ends in a thermocurable organopolysiloxane composition, and a 30 wt% toluene solution has a viscosity of 10,000 cP or more at 25 ° C. Light polydiorganosiloxane having a viscosity at 25 ° C. of 5,000 to 500,000 cP, containing 8 to 20 mol% of aryl groups bonded to dimethylpolysiloxane and silicon atoms at both ends and bonded to silicon atoms. It has been proposed to add it as a stripping additive.
In the present invention, the exposure resistance is excellent and light peeling occurs at low speed and high speed peeling. However, since the light peeling additive is not a cross-linking component, there is an extremely high possibility that the residual adhesion rate will decrease.

According to Japanese Patent No. 3149306 (Patent Document 5), the cationically polymerizable organopolysiloxane and the light peeling additive are non-reactive with no hydroxyl groups at both ends and have a viscosity of 50 to 1,000,000 cP at 25 ° C. UV curable compositions containing an organopolysiloxane have been proposed.
In the present invention, the cured film is made slippery and lightly peeled off from various adhesive substances. However, since the lightly peeled additive is a non-reactive component, there is an extremely high possibility that the residual adhesive ratio will decrease.

As described above, a light release additive useful for radically polymerizable organopolysiloxane containing a (meth) acrylic group has not yet been found.

On the other hand, the odor remaining on the release sheet having the cured film of the organopolysiloxane composition may be a problem. In particular, as a radically polymerizable organopolysiloxane composition containing a (meth) acrylic group, curing of a radiation-curable silicone composition comprising a radically polymerizable organopolysiloxane containing a (meth) acrylic group and a radical polymerization initiator. When a product is formed, the odor of the decomposition initiator is likely to remain slightly.

For example, radically polymerizable organopolysiloxane containing a (meth) acrylic group is used as a release agent for adhesive tapes of sanitary materials such as sanitary napkins and disposable diapers. Sanitary napkins and disposable diapers are individually wrapped for use and hygiene. In particular, for individual wrapping films for napkins, a film such as a polyethylene film is subjected to a mold release treatment, and the wrapping is performed so that the release treatment film is brought into contact with the adhesive layer of the napkin body for fixing to underwear. Therefore, the above-mentioned radiation-curable silicone composition is very often used for producing the release surface.

Sanitary napkins often give off an odor with fragrances, but due to the diversification of consumers, there have been increasing demands for odorless sanitary napkins in recent years.
It is also necessary to deodorize the napkin body and adhesive layer to be used, but the release-treated individual wrapping film that is peeled off before using the napkin body also touches the hands of consumers before using the napkin. Deodorization of this is also required.

In order to deal with these problems, various inventions have been proposed for deodorizing a cured film obtained by curing a radically polymerizable organopolysiloxane containing a (meth) acrylic group.

Japanese Patent No. 2791679 (Patent Document 6) describes radical polymerization initiator and radical polymerization initiator obtained by reacting a radical polymerization initiator containing a primary hydroxyl group with a monoisocyanate having one acryloyl group or a methacryloyl group in the molecule. A cured film having no unpleasant odor, which is characterized by curing a photocurable coating agent containing a substance, has been proposed.
In the present invention, by introducing a polymerizable ethylenically unsaturated group into the radical initiator, an unreacted excess initiator that is not involved in radical polymerization is also incorporated into the crosslinked cured composition, so that there is no unpleasant odor, but irradiation is performed. Since sometimes the volatile components generated by the decomposition of the radical polymerization initiator cannot be removed, there is still a problem in completely deodorizing.

Japanese Patent No. 4214579 (Patent Document 7) proposes an active energy ray-curable ink containing a photopolymerizable maleimide derivative.
In the present invention, a photopolymerizable maleimide derivative having a specific structure is used as a radical polymerization initiator to prevent an offensive odor during curing and yellowing of the cured film, but the description is limited to the description of a hydrocarbon-based maleimide derivative. It is considered that the solubility in the siloxane resin is extremely poor.

Japanese Patent No. 2583677 Japanese Patent No. 2669947 Japanese Patent No. 3780113 Japanese Patent No. 2971357 Japanese Patent No. 3149306 Japanese Patent No. 2791679 Japanese Patent No. 4214579

The present invention has been made in view of the above circumstances, and is a light peeling addition for a radiation-curable release sheet that can be blended in a radiation-curable organopolysiloxane composition for a release sheet that can be made into an odorless release sheet by light peeling. An object of the present invention is to provide a radiation-curable organopolysiloxane composition for a release sheet containing an agent and the additive, a release sheet having a cured film of the composition, and a method for producing the same.

As a result of diligent studies to achieve the above object, the present inventors used an organopolysiloxane having a maleimide group as a light peeling additive for a radiation-curable release sheet, and the cured film was lightly peeled and highly retained. It was found that the adhesion rate was obtained.
Further, since the organopolysiloxane having a maleimide group itself acts as a radical polymerization initiator, the amount of the radical polymerization initiator added can be reduced or does not need to be added, and radiation using the organopolysiloxane having the maleimide group is not necessary. It has been found that the release sheet obtained by curing the cured organopolysiloxane composition does not have the decomposition odor of the conventional radical polymerization initiator, so that the release sheet coated and cured on the substrate is odorless.
Therefore, the radiation-curable organopolysiloxane composition for a release sheet of the present invention has light peeling, a high residual adhesion rate, and the cured film is odorless as compared with the conventional radiation-curable organopolysiloxane composition. After confirming that, the present invention was made.

（式中、Ｒ¹は同一又は異種の炭素数１〜１０の非置換もしくは置換の１価炭化水素基、アルコキシ基、水酸基及び下記一般式（２）で表されるマレイミド構造を有する有機基から選択される基であり、Ｒ¹のうち少なくとも１個は下記一般式（２）で表されるマレイミド構造を有する有機基を含む。ａは２以上の整数、ｂは０以上の整数、ｃは０以上の整数、ｄは０以上の整数で、２≦ａ＋ｂ＋ｃ＋ｄ≦１，０００である。）

（式中、Ｒ²とＲ³は互いに同一又は異種の水素原子又は炭素数１〜５の非置換もしくは置換の１価炭化水素基であり、Ｘは炭素数１〜１０のヘテロ原子を介在してもよい非置換もしくは置換の２価炭化水素基である。破線は結合手を示す。）
〔２〕
式（１）のＲ¹中１〜１００ｍｏｌ％がマレイミド構造を有する有機基であることを特徴とする〔１〕記載の放射線硬化型剥離シート用軽剥離添加剤。
〔３〕
下記（Ａ）〜（Ｃ）成分を含有してなる剥離シート用放射線硬化型オルガノポリシロキサン組成物。
（Ａ）〔１〕又は〔２〕記載の放射線硬化型剥離シート用軽剥離添加剤：０．１〜１０質量部
（Ｂ）下記平均組成式（３）で示される（メタ）アクリル基を含有するラジカル重合性オルガノポリシロキサン：１００質量部

（式中、Ｒ⁴は同一又は異種の炭素数１〜１０の非置換もしくは置換の１価炭化水素基、アルコキシ基、水酸基及び（メタ）アクリル基を有する有機基から選択される基であり、Ｒ⁴のうち少なくとも１個は（メタ）アクリル基を有する有機基を含む。ｅは２以上の整数、ｆは０以上の整数、ｇは０以上の整数、ｈは０以上の整数で、２≦ｅ＋ｆ＋ｇ＋ｈ≦１，０００である。）
（Ｃ）放射線の照射によりラジカルを発生するラジカル重合開始剤：０〜２．５質量部
〔４〕
（Ｃ）ラジカル重合開始剤を含まない〔３〕記載の剥離シート用放射線硬化型オルガノポリシロキサン組成物。
〔５〕
〔３〕又は〔４〕記載の剥離シート用放射線硬化型オルガノポリシロキサン組成物を基材上に塗布し、放射線照射により硬化させた剥離シートの製造方法。
〔６〕
〔３〕又は〔４〕記載の剥離シート用放射線硬化型オルガノポリシロキサ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。
〔７〕
硬化皮膜が無臭である〔６〕記載の剥離シート。 Therefore, the present invention provides the following light peeling additive for a radiation-curable release sheet, a radiation-curable organopolysiloxane composition for a release sheet, a release sheet, and a manufacturing method.
[1]
A light release additive for a radiation-curable release sheet composed of an organopolysiloxane having a maleimide group represented by the following average composition formula (1).

(In the formula, R ¹ is derived from the same or dissimilar unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms, an alkoxy group, a hydroxyl group and an organic group having a maleimide structure represented by the following general formula (2). It is a group to be selected, and at least one of R ¹ contains an organic group having a maleimide structure represented by the following general formula (2). A is an integer of 2 or more, b is an integer of 0 or more, and c is an integer of 0 or more. An integer of 0 or more, d is an integer of 0 or more, and 2 ≦ a + b + c + d ≦ 1,000.)

(In the formula, R ² and R ³ are hydrogen atoms that are the same or different from each other, or unsubstituted or substituted monovalent hydrocarbon groups having 1 to 5 carbon atoms, and X is intervening a hetero atom having 1 to 10 carbon atoms. It may be an unsubstituted or substituted divalent hydrocarbon group. The broken line indicates a bond.)
[2]
The light peeling additive for a radiation-curable release sheet according to [1], wherein ^{1 to} 100 mol% of R ^{1 of the} formula (1) is an organic group having a maleimide structure.
[3]
A radiation-curable organopolysiloxane composition for a release sheet containing the following components (A) to (C).
(A) Light peeling additive for radiation-curable release sheet according to [1] or [2]: 0.1 to 10 parts by mass (B) Contains (meth) acrylic group represented by the following average composition formula (3). Radical-polymerizable organopolysiloxane: 100 parts by mass

(In the formula, R ⁴ is a group selected from an unsubstituted or substituted monovalent hydrocarbon group having the same or different carbon atoms 1 to 10, an alkoxy group, a hydroxyl group and an organic group having a (meth) acrylic group. At least one of R ⁴ contains an organic group having a (meth) acrylic group. E is an integer of 2 or more, f is an integer of 0 or more, g is an integer of 0 or more, h is an integer of 0 or more, and 2 ≦ e + f + g + h ≦ 1,000.)
(C) Radical polymerization initiator that generates radicals by irradiation with radiation: 0 to 2.5 parts by mass [4]
(C) The radiation-curable organopolysiloxane composition for a release sheet according to [3], which does not contain a radical polymerization initiator.
[5]
A method for producing a release sheet, wherein the radiation-curable organopolysiloxane composition for a release sheet according to [3] or [4] is applied onto a substrate and cured by irradiation.
[6]
A release sheet obtained by forming a cured film of the radiation-curable organopolysiloxane composition for a release sheet according to [3] or [4] on a substrate.
[7]
The release sheet according to [6], wherein the cured film is odorless.

According to the present invention, when a small amount of an organopolysiloxane having a maleimide group is added as a light peeling additive to a radiation-curable organopolysiloxane composition for a peeling sheet, unprecedented light peeling occurs. Further, since the organopolysiloxane having a maleimide group also acts as a radical polymerization initiator, the amount of the radical polymerization initiator added can be reduced or does not need to be added. Therefore, a release sheet obtained by curing the above composition. Is odorless because the decomposition odor of the conventional radical polymerization initiator is small or does not have a decomposition odor.

（式中、Ｒ¹は同一又は異種の炭素数１〜１０の非置換もしくは置換の１価炭化水素基、アルコキシ基、水酸基及び下記一般式（２）で表されるマレイミド構造を有する有機基から選択される基であり、Ｒ¹のうち少なくとも１個は下記一般式（２）で表されるマレイミド構造を有する有機基を含む。ａは２以上の整数、ｂは０以上の整数、ｃは０以上の整数、ｄは０以上の整数で、２≦ａ＋ｂ＋ｃ＋ｄ≦１，０００である。）

（式中、Ｒ²とＲ³は互いに同一又は異種の水素原子又は炭素数１〜５の非置換もしくは置換の１価炭化水素基であり、Ｘは炭素数１〜１０のヘテロ原子を介在してもよい非置換もしくは置換の２価炭化水素基である。破線は結合手を示す。） The light peeling additive for a radiation-curable peeling sheet of the present invention is composed of an organopolysiloxane containing a maleimide group represented by the following average composition formula (1).

(In the formula, R ¹ is derived from the same or dissimilar unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms, an alkoxy group, a hydroxyl group and an organic group having a maleimide structure represented by the following general formula (2). It is a group to be selected, and at least one of R ¹ contains an organic group having a maleimide structure represented by the following general formula (2). A is an integer of 2 or more, b is an integer of 0 or more, and c is an integer of 0 or more. An integer of 0 or more, d is an integer of 0 or more, and 2 ≦ a + b + c + d ≦ 1,000.)

(In the formula, R ² and R ³ are hydrogen atoms that are the same or different from each other, or unsubstituted or substituted monovalent hydrocarbon groups having 1 to 5 carbon atoms, and X is intervening a hetero atom having 1 to 10 carbon atoms. It may be an unsubstituted or substituted divalent hydrocarbon group. The broken line indicates a bond.)

In the above formula (1), R ¹ is 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, a vinyl group, an allyl group, a butenyl group, an alkenyl group such as an octenyl group. , Aryl groups such as phenyl group and trill group, and a part or all of hydrogen atoms bonded to carbon atoms of these groups are hydroxy group, cyano group, halogen atom, amino group and epoxy group. , An unsubstituted or substituted carbon number 1 selected from a hydroxypropyl group, a cyanoethyl group, a 1-chloropropyl group, a 3,3,3-trifluoropropyl group, a 1-aminopropyl group and the like substituted with an alkoxy group or the like. Examples thereof include an alkoxy group such as a monovalent hydrocarbon group, a methoxy group, an ethoxy group, an isopropoxy group, and a butoxy group, a hydroxyl group, and an organic group having a maleimide structure represented by the above general formula (2). As the group other than the organic group having a maleimide structure represented by the formula (2) of R ¹ , a saturated aliphatic group or aromatic group is preferable, and a methyl group and a phenyl group are preferable. Further, it is desirable that 80 mol% or more, particularly 85 mol% or more of R ¹ excluding the maleimide group is an alkyl group, and more preferably a methyl group.

In the present invention, at least one of R ¹ contains an organic group having a maleimide structure represented by the general formula (2), and ^{1 to} 100 mol%, particularly 2 to 80 mol% of R ¹ has a maleimide structure. It is preferable that it is an organic group having.

In the above formula (2), R ² and R ³ are hydrogen atoms that are the same as or different from each other, or unsubstituted or substituted monovalent hydrocarbon groups having 1 to 5 carbon atoms. Examples of the monovalent hydrocarbon group include alkyl groups such as a methyl group, an ethyl group, a propyl group and a butyl group, and further, a part or all of the hydrogen atoms bonded to the carbon atoms of these groups are halogen. It may be substituted with an atom or other group, and examples of the substituent include a trifluoromethyl group, a 3,3,3-trifluoropropyl group, and a hydrogen atom and a methyl group are preferable.

X is an unsubstituted or substituted divalent hydrocarbon group which may interpose a heteroatom having 1 to 10 carbon atoms, and is CH ₂ , C ₂ H ₄ , C ₃ H ₆ , C ₄ H ₈ , C ₅ H. Examples thereof include an alkylene group such as ₁₀ , C ₆ H _12, and an ether group, a thioether group, or the like may be interposed. Further, a cyclic structure such as a phenylene group or a cyclohexylene group may be formed, or a part or all of a hydrogen atom bonded to a carbon atom may be substituted with a halogen atom or another group.

（式中、破線は結合手を示す。） The specific structure of the general formula (2) is shown below, but the structure is not limited thereto.

(In the formula, the broken line indicates the bond.)

In the above formula (1), a is 2 or more, preferably an integer of 2 to 12, b is 0 or more, preferably 1 to 998, more preferably an integer of 5 to 500, and c is 0 or more, preferably 0 to 10. The integer of d is 0 or more, preferably an integer of 0 to 5, 2 ≦ a + b + c + d ≦ 1,000, and 2 ≦ a + b + c + d ≦ 800 is preferable. If a + b + c + d is larger than 1,000, the viscosity may increase and workability may deteriorate.

（ｐ≧０，ｑ≧１。破線は結合手を示す。）

（ｐ１≧０，ｐ２≧０，ｐ３≧０，Ｐ≧１。破線は結合手を示す。） Specific structures of the organopolysiloxane represented by the formula (1) include, but are not limited to, those represented by the following general formula. In the following formula, Me and Ph represent a methyl group and a phenyl group, respectively, and I represents an N-maleimidepropyl group, respectively, but any organic group having a structure represented by the formula (2) can be used. It may be one.

(P ≧ 0, q ≧ 1. The broken line indicates the bond.)

(P1 ≧ 0, p2 ≧ 0, p3 ≧ 0, P ≧ 1. The broken line indicates the bond.)

（式中、Ｒ²、Ｒ³は上記と同じである。） The organopolysiloxane containing a maleimide group represented by the formula (1) includes an organopolysiloxane (a) having at least one amino group-containing organic group in one molecule and an organic compound represented by the following general formula (4) ( It can be synthesized by subjecting b) to an addition reaction in the presence of an organic solvent, if necessary, and then subjecting it to a condensation reaction (imidization reaction) using a Lewis acid catalyst (c) and a silylating agent (d). ..

(In the formula, R ² and R ³ are the same as above.)

（式中、Ｒ⁵は同一又は異種の炭素数１〜１０の非置換もしくは置換（好ましくはヒドロキシ基、シアノ基、ハロゲン原子、エポキシ基もしくはアルコキシ基置換）の１価炭化水素基、アルコキシ基、水酸基及びアミノ基含有有機基から選択される基であり、Ｒ⁵のうち少なくとも１個はアミノ基含有有機基を含む。ａ、ｂ、ｃ、ｄ、ａ＋ｂ＋ｃ＋ｄは上記と同じである。） As the organopolysiloxane (a) having at least one amino group-containing organic group in one molecule, the one represented by the following average composition formula (5) can be used.

(In the formula, R ⁵ is an unsubstituted or substituted (preferably hydroxy group, cyano group, halogen atom, epoxy group or alkoxy group substituted) monovalent hydrocarbon group or alkoxy group having the same or different carbon atoms of 1 to 10. It is a group selected from a hydroxyl group and an amino group-containing organic group, and at least one of R ⁵ contains an amino group-containing organic group. A, b, c, d, a + b + c + d are the same as above.)

In the above formula (5), R ⁵ is 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, a vinyl group, an allyl group, a butenyl group, an alkenyl group such as an octenyl group. , Aryl groups such as phenyl group and trill group, and a part or all of hydrogen atoms bonded to the carbon atom of these groups are hydroxy group, cyano group, halogen atom, epoxy group and alkoxy group. An unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms selected from a hydroxypropyl group, a cyanoethyl group, a 1-chloropropyl group, a 3,3,3-trifluoropropyl group and the like substituted with, etc. Examples thereof include an alkoxy group such as a methoxy group, an ethoxy group, an isopropoxy group and a butoxy group, a hydroxyl group, and an amino group-containing organic group described later. As the group other than the amino group-containing organic group of R ⁵ , a saturated aliphatic group or aromatic group is preferable, and a methyl group and a phenyl group are preferable.

（式中、破線は結合手を示す。） The amino group in the amino group-containing organic group of R ⁵ is a primary amine or a secondary amine, and a primary amine is preferable from the viewpoint of reactivity. As the amino group-containing organic group, for example, an aminoalkyl group having 1 to 10 carbon atoms which may be interposed such as an ether group or a thioether group is preferable, and an aminopropyl group is particularly preferable. The specific structure of the amino group-containing organic group is shown below, but the structure is not limited thereto.

(In the formula, the broken line indicates the bond.)

The amine equivalent of the component (a) is preferably 200 to 5,000 g / mol, more preferably 300 to 4,800 g / mol, and even more preferably 400 to 4,500 g / mol. If it is less than 200 g / mol, the effect of the light peeling additive may be small, and if it is more than 5,000 g / mol, the amount of functional groups to be introduced is small and the effect as a radical polymerization initiator is weakened. There is.

（ｒ≧０，ｓ≧１。破線は結合手を示す。）

（ｒ１≧０，ｒ２≧０，ｒ３≧０，Ｒ≧１。破線は結合手を示す。） Specific structures of the component (a) include, but are not limited to, those represented by the following general formulas. In the following formula, Me and Ph represent a methyl group and a phenyl group, respectively, and A represents an aminopropyl group, respectively, but any amino group-containing organic group may be used.

(R ≧ 0, s ≧ 1. The broken line indicates the bond.)

(R1 ≧ 0, r2 ≧ 0, r3 ≧ 0, R ≧ 1. The broken line indicates the bond.)

（式中、Ｒ²、Ｒ³は上記と同じである。） The organic compound (b) to be reacted with the organopolysiloxane (a) having an amino group-containing organic group is represented by the following general formula (4).

(In the formula, R ² and R ³ are the same as above.)

Specific examples of the component (b) include maleic anhydride, methyl maleic anhydride, and phenylmaleic anhydride.

As the component (b), an amount that is 1 to 3 times the mol ratio of the amino group of the component (a) is used, preferably 1 to 2.5 times, more preferably 1 to 2 times. If it is less than 1 times, unreacted amino groups remain, so that the characteristics as a light peeling additive deteriorate, and the action as a radical polymerization initiator may deteriorate. If it is more than 3 times, it does not react at the time of purification. The efficiency may be reduced due to the removal of the component (b) of.

The component (c) is a Lewis acid catalyst, and various examples of Lewis acid include boron compounds, aluminum compounds, scandium compounds, titanium compounds, vanadium compounds, iron compounds, cobalt compounds, nickel compounds, copper compounds, and zinc. There are compounds, lanthanum compounds, cerium compounds and the like, and metal compounds are preferable, and zinc compounds are particularly preferable.

As the zinc compound, zinc halide compounds such as zinc chloride, zinc bromide and zinc iodide, and inorganic zinc compounds such as zinc salts such as zinc nitrate, zinc sulfate, zinc carbonate and zinc trifluoromethanesulfonate are preferably used. , Zinc chloride, zinc bromide are preferred.

As the component (c), an amount that is 0.1 to 2 times the mol ratio of the amino group of the component (a) is used, preferably 0.2 to 1.8 times, more preferably 0.5 to 1. It is 5.5 times. If it is less than 0.1 times, the reaction may be slow and may take a long time, and if it is more than 2 times, it may be removed from the reaction system, resulting in inefficiency.

The component (d) is a silylating agent, and examples of the silylating agent include chlorosilane compounds and disilazane compounds, but disilazan compounds are preferable.
Examples of the disilazane compound include hexamethyldisilazane, 1,1,3,3-tetramethyldisilazane, 1,3-divinyl-1,1,3,3-tetramethyldisilazane, 1,3-diphenyl-1, Examples thereof include 1,3,3-tetramethyldisilazane, but hexamethyldisilazane is preferable.

As the component (d), an amount that is 1 to 3 times the mol ratio of the amino group of the component (a) is used, preferably 1.1 to 2.8 times, more preferably 1.2 to 2.5 times. It is double. If it is less than 1 times, the reaction may not proceed sufficiently, and if it is more than 3 times, it may be removed from the reaction system, resulting in inefficiency.

The synthesis of the organopolysiloxane containing the maleimide group can be carried out in an organic solvent. Aromatic hydrocarbon solvents such as toluene and xylene, aliphatic hydrocarbon solvents such as hexane, heptane, octane, isooctane, decane, cyclohexane, methylcyclohexane and isoparaffin, and hydrocarbons such as industrial gasoline, petroleum benzine and solvent naphtha. Solvents, acetone, methyl ethyl ketone, 2-pentanone, 3-pentanone, 2-hexanone, 2-heptanone, 4-heptanone, methylisobutylketone, diisobutylketone, acetonylacetone, cyclohexanone and other ketone solvents, ethyl acetate, propyl acetate , Ester solvents such as isopropyl acetate, butyl acetate, isobutyl acetate, ether solvents such as diethyl ether, dipropyl ether, diisopropyl ether, dibutyl ether, 1,2-dimethoxyethane, 1,4-dioxane, 2-methoxyethyl Examples thereof include a solvent having an ester and an ether portion such as an acetate, 2-ethoxyethyl acetate, propylene glycol monomethyl ether acetate, 2-butoxyethyl acetate, or a mixed solvent thereof. These can be used alone or in combination of two or more.

The organic solvent is preferably a solvent that dissolves the component (a) and the component (d) but does not dissolve the component (c). This is because the component (c) can be easily removed after the reaction is completed. If the component (c) is not dissolved, it can be removed by filtration, whereas the component (c) is dissolved. This is because a cleaning operation is required and the efficiency and yield are deteriorated. The component (b) may or may not be dissolved in an organic solvent, but it is preferable to dissolve the component (b) because the reaction proceeds faster.

The amount of the organic solvent used is, when the component (a) is 100 parts by mass, 0 to 5,000 parts by mass, preferably 0 to 4,000 parts by mass, and 0 to 3,000 parts by mass. preferable. If it is more than 5,000 parts by mass, the progress of the reaction may be slowed down. When blended, it is preferably 500 parts by mass or more.

（式中、Ｒ⁶は同一又は異種の炭素数１〜１０の非置換もしくは置換の１価炭化水素基、アルコキシ基、水酸基及び下記一般式（７）で表される構造の有機基から選択される基であり、Ｒ⁶のうち少なくとも１個は下記一般式（７）で表される構造の有機基を含む。ａ、ｂ、ｃ、ｄ、ａ＋ｂ＋ｃ＋ｄは上記と同じである。）

（式中、Ｒ²、Ｒ³、Ｘは上記と同じである。破線は結合手を示す。） As described above, when the component (a) and the component (b) are mixed in the presence of an organic solvent, if necessary, they react with heat even at room temperature (25 ° C.) and are represented by the following average composition formula (6). Organopolysiloxane (e) is formed.

(In the formula, R ⁶ is selected from the same or dissimilar unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms, an alkoxy group, a hydroxyl group and an organic group having a structure represented by the following general formula (7). At least one of R ⁶ contains an organic group having a structure represented by the following general formula (7). A, b, c, d, a + b + c + d are the same as above.)

(In the formula, R ² , R ³ , and X are the same as above. The broken line indicates the bond.)

In the above formula (6), R ⁶ is 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, a vinyl group, an allyl group, a butenyl group, an alkenyl group such as an octenyl group. , Aryl groups such as phenyl group and trill group, and a part or all of hydrogen atoms bonded to carbon atoms of these groups are hydroxy group, cyano group, halogen atom, amino group and epoxy group. , An unsubstituted or substituted carbon number 1 selected from a hydroxypropyl group, a cyanoethyl group, a 1-chloropropyl group, a 3,3,3-trifluoropropyl group, a 1-aminopropyl group and the like substituted with an alkoxy group or the like. Examples thereof include an alkoxy group such as a monovalent hydrocarbon group of 10 to 10, a methoxy group, an ethoxy group, an isopropoxy group and a butoxy group, a hydroxyl group, and an organic group having a structure represented by the above general formula (7). As the group other than the organic group having the structure represented by the formula (7) of R ⁶ , a saturated aliphatic group or aromatic group is preferable, and a methyl group and a phenyl group are preferable.
Of R ⁶ , at least one, preferably 2 to 200, more preferably 2 to 150 contains an organic group having a structure represented by the general formula (7).

（式中、破線は結合手を示す。） The specific structure of the general formula (7) is shown below, but the structure is not limited thereto.

(In the formula, the broken line indicates the bond.)

（ｔ≧０，ｕ≧１。破線は結合手を示す。）

（ｔ１≧０，ｔ２≧０，ｔ３≧０，Ｔ≧１。破線は結合手を示す。） Specific structures of the component (e) include, but are not limited to, those represented by the following general formulas. In the formula below, Me and Ph represent a methyl group and a phenyl group, respectively, and B represents a structure represented by the following, but any organic group having a structure represented by the formula (7) can be used. It may be.

(T ≧ 0, u ≧ 1. The broken line indicates the bond.)

(T1 ≧ 0, t2 ≧ 0, t3 ≧ 0, T ≧ 1. The broken line indicates the bond.)

Next, the component (c) and the component (d) are mixed, and the amide group and the carboxyl group in the component (e) are ring-closed and imidized by a condensation reaction to form an organopolysiloxane of the above formula (1). Can be obtained.
Here, the component (c) is a catalyst, and the component (d) is a reaction reagent for silylcapping the carboxyl group in the component (e). When the component (e) and the component (c) are mixed and the component (d) is added thereto, the carboxyl group in the component (e) is silylated, and the silylated carboxyl group and amide group are formed by heating. The organopolysiloxane of the formula (1) can be obtained by condensation. Condensation is unlikely to occur with a carboxyl group, but silylation facilitates condensation. At this time, the component (c) has two roles of producing an active species for silylation by reacting with the component (d), and catalyzing the condensation reaction, although the detailed mechanism is not certain. It is presumed that it is.

After the completion of imidization, ammonia generated from the component (d) is present in the system, and it is necessary to remove it. The method for removing ammonia is not particularly limited, and examples thereof include a method of reacting with an acidic substance to neutralize and then filtering the produced salt. Examples of acidic substances include hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, boric acid, formic acid, acetic acid, citric acid, lactic acid, butyric acid and the like. From the viewpoint of reactivity, the acidic substance is preferably liquid, and acetic acid or phosphoric acid is preferable.

If the component (c) is insoluble in an organic solvent, it can be removed by filtration. If it is dissolved in an organic solvent, it must be washed by liquid-liquid extraction and discharged to the outside of the system.
Further, the unreacted component (b) and component (d) and the organic solvent can be removed by distillation under reduced pressure.

In this way, an organopolysiloxane containing a maleimide group represented by the above formula (1) can be produced.

The maleimide group-containing organopolysiloxane represented by the above formula (1) can be used as a light peeling additive for a radiation-curable release sheet, and can be blended in a radiation-curable organopolysiloxane composition for a release sheet. it can.

（式中、Ｒ⁴は同一又は異種の炭素数１〜１０の非置換もしくは置換の１価炭化水素基又は（メタ）アクリル基を有する有機基であり、Ｒ⁴のうち少なくとも１個は（メタ）アクリル基を有する有機基を含む。ｅは２以上の整数、ｆは０以上の整数、ｇは０以上の整数、ｈは０以上の整数で、２≦ｅ＋ｆ＋ｇ＋ｈ≦１，０００である。）
（Ｃ）放射線の照射によりラジカルを発生するラジカル重合開始剤。 The radiation-curable organopolysiloxane composition for the release sheet may contain the following components (A) and (B), and if necessary, the component (C).
(A) A light peeling additive for a radiation-curable peeling sheet made of an organopolysiloxane having a maleimide group represented by the above formula (1).
(B) A radically polymerizable organopolysiloxane containing a (meth) acrylic group represented by the following average composition formula (3).

(In the formula, R ⁴ is an organic group having the same or different unsubstituted or substituted monovalent hydrocarbon group or (meth) acrylic group having 1 to 10 carbon atoms, and at least one of R ⁴ is (meth). ) Includes an organic group having an acrylic group. E is an integer of 2 or more, f is an integer of 0 or more, g is an integer of 0 or more, h is an integer of 0 or more, and 2 ≦ e + f + g + h ≦ 1,000.)
(C) A radical polymerization initiator that generates radicals by irradiation with radiation.

Since the organopolysiloxane containing the maleimide group represented by the above formula (1) of the component (A) generates radicals by irradiation with radiation, it can also be used as a radical polymerization initiator. Further, the organopolysiloxane containing a maleimide group acts as a radical polymerization initiator, but since it is incorporated into the cured film, the amount of the conventional radical polymerization initiator added can be reduced, or the radical polymerization initiator is not added. Even in this case, radical polymerization is possible.

Hereinafter, each component will be described in detail.

The component (A) is a light peeling additive for a radiation-curable release sheet made of an organopolysiloxane having a maleimide group represented by the above formula (1). The amount of the light peeling additive for a radiation-curable release sheet used is 0.1 to 10 parts by mass, preferably 0.5 to 9 parts by mass with respect to 100 parts by mass of the component (B) described later. If the amount of the component (A) is too large, the light peeling effect does not change, and if it is too small, the light peeling effect is small and the curability is also lowered.

（式中、Ｒ⁴は同一又は異種の炭素数１〜１０の非置換もしくは置換の１価炭化水素基、アルコキシ基、水酸基及び（メタ）アクリル基を有する有機基から選択される基であり、Ｒ⁴のうち少なくとも１個は（メタ）アクリル基を有する有機基を含む。ｅは２以上の整数、ｆは０以上の整数、ｇは０以上の整数、ｈは０以上の整数で、２≦ｅ＋ｆ＋ｇ＋ｈ≦１，０００である。） The component (B) is a radically polymerizable organopolysiloxane containing a (meth) acrylic group, and is represented by the following average composition formula (3).

(In the formula, R ⁴ is a group selected from an unsubstituted or substituted monovalent hydrocarbon group having the same or different carbon atoms 1 to 10, an alkoxy group, a hydroxyl group and an organic group having a (meth) acrylic group. At least one of R ⁴ contains an organic group having a (meth) acrylic group. E is an integer of 2 or more, f is an integer of 0 or more, g is an integer of 0 or more, h is an integer of 0 or more, and 2 ≦ e + f + g + h ≦ 1,000.)

In the above formula (3), R ⁴ is 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 group thereof. A hydroxypropyl group, a cyanoethyl group, a 1-chloropropyl group, in which a part or all of the hydrogen atom bonded to the carbon atom is replaced with a hydroxy group, a cyano group, a halogen atom, an amino group, an epoxy group, an alkoxy group, etc. Unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms, methoxy group, ethoxy group, isopropoxy group, butoxy group selected from 3,3,3-trifluoropropyl group, 1-aminopropyl group and the like. It is an organic group (radical polymerizable functional group) having an alkoxy group such as, hydroxyl group, and (meth) acrylic group.
Further, it is desirable that 80 mol% or more of R ⁴ excluding the organic group having a (meth) acrylic group is an alkyl group, and more preferably a methyl group.

（式中、破線は結合手を示す。） The organic group having a (meth) acrylic group preferably has 2 to 20 carbon atoms, and specifically, a (meth) acrylicoxyalkyl group such as a γ-acryloxypropyl group or a γ-methacryloxypropyl group. The following groups such as a group and a (meth) acrylicoxyalkoxy group can be exemplified.

(In the formula, the broken line indicates the bond.)

In the present invention, at least one of R ⁴ contains an organic group (radical polymerizable functional group) having a (meth) acrylic group, and in particular, the amount of (meth) acrylic group in R ⁴ is 1 to 50 mol. %, More preferably 2 to 45 mol%, still more preferably 3 to 40 mol%. If the amount of (meth) acrylic group is less than the above lower limit, the curing rate may be slowed down and curing may be poor.

e is 2 or more, preferably an integer of 2 to 12, f is 0 or more, preferably 1 to 998, more preferably an integer of 5 to 500, g is 0 or more, preferably an integer of 0 to 10, and h is 0 or more. It is preferably an integer of 0 to 5, and is 2 ≦ e + f + g + h ≦ 1,000, preferably 2 ≦ e + f + g + h ≦ 800. If e + f + g + h is larger than 1,000, the viscosity may increase and workability may deteriorate.

The radically polymerizable organopolysiloxane containing the (meth) acrylic group represented by the above formula (3) can be obtained by reacting the (meth) acrylic functional group-containing compound shown below with the siloxane shown below. be able to.

Examples of the (meth) acrylic functional group-containing compound include 2-hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, hydroxybutyl acrylate, 2-hydroxypropyl acrylate, diethylene glycol monoacrylate, pentaerythritol monoacrylate, and pentaerythritol diacrylate. It has 2 to 20 carbon atoms having a (meth) acrylic oxyalkyl group such as hydroxyfunctional (meth) acrylate selected from pentaerythritol triacrylate and pentaerythritol trimethacrylate, γ-acryloxypropyl, and γ-methacryloxypropyl. Examples of the (meth) acrylic functional group-containing compound, acrylic acid, and methacrylic acid.

Examples of the siloxane that reacts with the (meth) acrylic functional group-containing compound include carbinol-modified siloxane, epoxy-modified siloxane, and hydrosilyl group-containing siloxane.

The reaction between the (meth) acrylic functional group-containing compound and siloxane includes the dehydrogenation reaction of carbinol-modified siloxane and hydroxy-functional (meth) acrylate, and the esterification reaction of carbinol-modified siloxane and (meth) acrylic acid. Examples thereof include a ring-opening reaction between an epoxy-modified siloxane and (meth) acrylic acid, and a hydrosilylation reaction between a hydrosilyl group-containing siloxane and an alkenyl group-containing (meth) acrylate.

The component (C) is a radical polymerization initiator that generates radicals by irradiation with radiation.
The radical polymerization initiator is a radical polymerization initiator that is soluble in radically polymerizable organopolysiloxane (B), and its use is not particularly limited as long as it has the ability to generate radicals by irradiation. Specifically, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 4'-isopropyl-2-hydroxy-2-methylpropiophenone, 2-hydroxymethyl-2-methyl Propiophenone, 2,2-dimethoxy-1,2-diphenylethane-1-one, p-dimethylaminoacetophenone, p-tershaributyldichloroacetophenone, p-tershaributyltrichloroacetophenone, p-azidobenzalacetophenone, 1-Hydroxycyclohexylphenylketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropanone-1, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone -1, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin-n-butyl ether, benzoin isobutyl ether, benzyl, anisyl, benzophenone, o-benzoyl methyl benzoate, Michler ketone, 4,4'-bisdiethylaminobenzophenone , 4,4'-Dichlorobenzophenone, 4-benzoyl-4'-methyldiphenylsulfide, thioxanthone, 2-methylthioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, 2-isopropylthioxanthone, 2,4-diethylthioxanthone, bis (Cyclopentadienyl) -bis (2,6-difluoro-3- (pyr-1-yl) titanium, 1- (4- (2-hydroxyethoxy) phenyl) -2-hydroxydi-2-methyl-1 -Propane-1-one and the like can be mentioned.
As these radical polymerization initiators, one kind or two or more kinds can be blended and used according to a desired performance.

The amount of the radical polymerization initiator (C) blended is 0 to 2.5 parts by mass, more preferably 0 to 2 parts by mass, still more preferably 0 to 0 parts by mass with respect to 100 parts by mass of the radically polymerizable organopolysiloxane (B). It is 1 part by mass, and the radical polymerization initiator can be substantially 0 parts by mass.

A release sheet obtained by curing a radiation-curable organopolysiloxane composition composed of a radically polymerizable organopolysiloxane (B) and a radical polymerization initiator (C) usually has a volatile odor of a decomposition product of the radical polymerization initiator. This is the cause of the odor. The release sheet obtained by curing the radiation-curable organopolysiloxane composition for a release sheet containing the light release additive (A) for a radiation-curable release sheet containing an organopolysiloxane having a maleimide group of the present invention is odorless. However, the smaller the amount of the radical polymerization initiator (C) added, the less the odor.

The radiation-curable organopolysiloxane composition for a release sheet of the present invention can be obtained by blending a predetermined amount of each of the above components, but in addition to each of the above components, silicone resin, dimethylpolysiloxane, and filling as optional components. Additives such as agents, antistatic agents, flame retardants, defoamers, flow modifiers, light stabilizers, solvents, non-reactive resins and radically polymerizable compounds can be used. The amount of these optional components added can be a normal amount as long as the effects of the present invention are not impaired.

The radiation-curable organopolysiloxane composition for a release sheet of the present invention can be used by diluting it with an organic solvent as the case may be.

The radiation-curable organopolysiloxane composition for a release sheet prepared in this manner is applied to various substrates and radiation-cured. 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.

As a method for applying the radiation-curable organopolysiloxane composition for a release sheet, known methods such as roll coating, gravure coating, wire doctor coating, air knife coating, and dipping coating can be used.
The amount of the radiation-curable organopolysiloxane composition for a release sheet applied is not particularly limited, but is usually about 0.05 to 3 g / m ² .

In order to cure by irradiation, the radiation energy rays are preferably high-pressure or ultra-high pressure mercury lamps, metal halide lamps, xenon lamps, carbon arc lamps, fluorescent lamps, semiconductor solid-state lasers, argon lasers, He-Cd lasers, KrF. Energy rays in the ultraviolet to visible light region (about 100 to about 800 nm) obtained from an excimer laser, an ArF excimer laser, an F ₂ laser, or the like are used. A radiation light source having a strong light hardness of 200 to 400 nm is preferable. Further, radiation having high energy such as electron beam and X-ray can be used. The irradiation temperature and 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 of the curable composition is thick. It may be preferable to spend more time on this. 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.

Since the release sheet thus obtained contains the above-mentioned light release additive for a radiation-curable release sheet made of organopolysiloxane having a maleimide group, the desired light release is possible, and further, radicals can be obtained. Since the amount of the polymerization initiator added can be reduced or does not need to be added, the radical polymerization initiator has little decomposition odor or no decomposition odor, and is therefore odorless.

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 at 25 ° C. measured with a BN type rotational viscometer. In the structural formula, Me represents a methyl group and AO represents an acryloxy group.

[Synthesis Example 1]
3.14 g (0.032 mol) of maleic anhydride as a component (b) and toluene as a component (e) 81. in a 300 mL three-necked flask equipped with a stirrer, a thermometer, a dropping funnel, and a reflux condenser. When 74 g (70% by mass) was charged and mixed and stirred at room temperature (25 ° C.), 13.76 g (amino group) of the organopolysiloxane of the following formula (a-1) was charged into the dropping funnel as the component (a). 0.032 mol) was added dropwise. After completion of the dropping, the mixture was stirred at room temperature (25 ° C.) for 4 hours, 7.20 g (0.032 mol) of zinc bromide was added to the flask as the component (c), and the mixture was heated to 50 ° C. 7.76 g (0.048 mol) of hexamethyldisilazane charged in the dropping funnel as the component (d) was added dropwise thereto, and after the completion of the dropping, the mixture was aged at 80 ° C. for 1 hour and allowed to cool to 40 ° C. or lower. 3.17 g (0.053 mol) of acetic acid was added dropwise and the mixture was further aged for 30 minutes. The solid in the reaction solution was removed by filtration, distilled off under reduced pressure at 70 ° C./1 hour, and then distilled off under reduced pressure at 120 ° C./1 hour to obtain a transparent yellow liquid. As a result of the analysis, it was confirmed that the organopolysiloxane contained a maleimide group of the following formula (A-1).

[Synthesis Example 2]
A yellow transparent liquid was obtained in the same manner as in Synthesis Example 1 except that methyl maleic anhydride was changed to 3.59 g (0.032 mol) instead of maleic anhydride as a component (b). As a result of the analysis, it was confirmed that the organopolysiloxane contained a maleimide group of the following formula (A-2).

In order to evaluate the radiation-curable organopolysiloxane composition for a release sheet obtained in Examples and Comparative Examples shown below, the following tests were conducted.

[Curability test of radiation-curable organopolysiloxane composition for release sheet]
After preparing a radiation-curable organopolysiloxane composition for a release sheet, it is applied to a PET film having a thickness of 38 μm so as to have a coating amount of about 1.0 g / m ² , and the oxygen concentration is set to 150 ppm. The curability was evaluated by irradiating an irradiation amount of ultraviolet rays of 100 mJ / cm ² with two 80 W / cm high-pressure mercury lamps to form a cured film. ◯ indicates the case where the entire composition is cured, Δ indicates the case where the entire composition has smear, and × indicates the case where the entire composition is uncured. The results are summarized in Table 1.

[Peeling force test of radiation-curable organopolysiloxane composition for peeling sheet]
After preparing a radiation-curable organopolysiloxane composition for a release sheet, it is applied to a PET film having a thickness of 38 μm so as to have a coating amount of about 1.0 g / m ² , and the oxygen concentration is set to 150 ppm. A cured film was formed by irradiating an irradiation amount of ultraviolet rays of 100 mJ / cm ² with two 80 W / cm high-pressure mercury lamps. After storing the obtained cured film at 25 ° C. for 20 hours, an acrylic adhesive tape TESA7475 (trade name) having a width of 25 mm is attached to the surface of the cured film, and a 2 kg roller is reciprocated once to crimp it for peeling force measurement. A sample was prepared. The sample was aged at 70 ° C. for 20-24 hours under a load of 70 g / cm ² . Then, using a tensile tester, the force (N / 25 mm) required to pull and peel the bonded tape was measured at a peeling speed of 0.3 m / min at an angle of 180 °. The results are summarized in Table 1.

[Residual Adhesion Test of Radiation Curable Organopolysiloxane Composition for Release Sheet]
After preparing a radiation-curable organopolysiloxane composition for a release sheet, it is applied to a PET film having a thickness of 38 μm so as to have a coating amount of about 1.0 g / m ² , and the oxygen concentration is set to 150 ppm. A cured film was formed by irradiating an irradiation amount of ultraviolet rays of 100 mJ / cm ² with two 80 W / cm high-pressure mercury lamps. After storing the obtained cured film at 25 ° C. for 20 hours, an acrylic adhesive tape TESA7475 (trade name) having a width of 25 mm is attached to the surface of the cured film, and a 2 kg roller is reciprocated once to crimp it for peeling force measurement. A sample was prepared. The sample was aged at 70 ° C. for 20-24 hours under a load of 70 g / cm ² . Then, the bonded tape was peeled off at a peeling speed of 0.3 m / min at an angle of 180 ° using a tensile tester, and the tape was stuck on the SUS plate. A 2 kg roller was reciprocated once and crimped, and the force (Y) required for peeling after leaving at 25 ° C. for 30 minutes was measured. Similarly, the force (Z) required to peel the TESA7475 not bonded to the cured film from the SUS plate was measured, and the value obtained by dividing (Y) by (Z) was used as the residual adhesion ratio, and the results are shown in Table 1. I summarized it in.

[Smell measurement]
The odor of the prepared cured film was scored by 20 panelists according to the following criteria and evaluated by the average score. The results are summarized in Table 1.
4: Odorless 3: Slightly odor 2: Smell 1: Strong odor

で示され、２５℃における粘度が３００ｍＰａ・ｓであるアクリル基含有ジメチルポリシロキサン１００質量部、及び本発明成分である（Ｃ）成分に該当するラジカル重合開始剤２−ヒドロキシ−２−メチル−１−フェニル−プロパン−１−オン（Ｃ−１）２．５質量部を均一に混合することで、剥離シート用放射線硬化型オルガノポリシロキサン組成物１を得た。このオルガノポリシロキサン組成物１を用いて上記に記載の硬化性試験、剥離力試験、残留接着率試験、臭い測定を行なった。 [Example 1]
5 parts by mass of maleimide group-containing organopolysiloxane of the formula (A-1) obtained in Synthesis Example 1 corresponding to the component (A) of the present invention, the following average corresponding to the component (B) of the present invention Composition formula (B-1)

2-Hydroxy-2-methyl-1 radical polymerization initiator corresponding to 100 parts by mass of acrylic group-containing dimethylpolysiloxane having a viscosity of 300 mPa · s at 25 ° C. and component (C) of the present invention. By uniformly mixing 2.5 parts by mass of −phenyl-propane-1-one (C-1), a radiation-curable organopolysiloxane composition 1 for a release sheet was obtained. Using this organopolysiloxane composition 1, the curability test, peeling force test, residual adhesion rate test, and odor measurement described above were performed.

[Example 2]
The same as in Example 1 except that the component corresponding to the component (A), which is the component of the present invention, was changed to 5 parts by mass of the maleimide group-containing organopolysiloxane of the formula (A-2) obtained in Synthesis Example 2. By performing the procedure, a radiation-curable organopolysiloxane composition 2 for a release sheet was obtained. Using this organopolysiloxane composition 2, the curability test, peeling force test, residual adhesion rate test, and odor measurement described above were performed.

[Example 3]
Examples except that the radical polymerization initiator 2-hydroxy-2-methyl-1-phenyl-propane-1-one (C-1) corresponding to the component (C) of the present invention was changed to 0 parts by mass. By performing the same procedure as in No. 1, a radiation-curable organopolysiloxane composition 3 for a release sheet was obtained. Using this organopolysiloxane composition 3, the curability test, peeling force test, residual adhesion rate test, and odor measurement described above were performed.

[Example 4]
Examples except that the radical polymerization initiator 2-hydroxy-2-methyl-1-phenyl-propane-1-one (C-1) corresponding to the component (C) of the present invention was changed to 0 parts by mass. By performing the same procedure as in 2, a radiation-curable organopolysiloxane composition 4 for a release sheet was obtained. Using this organopolysiloxane composition 4, the curability test, peeling force test, residual adhesion rate test, and odor measurement described above were performed.

で示され、２５℃における粘度が４５０ｍＰａ・ｓであるアクリル基含有ジメチルポリシロキサン１００質量部に変更した以外は、実施例１と同様の手順を行なうことで、剥離シート用放射線硬化型オルガノポリシロキサン組成物５を得た。このオルガノポリシロキサン組成物５を用いて上記に記載の硬化性試験、剥離力試験、残留接着率試験、臭い測定を行なった。 [Example 5]
The component corresponding to the component (B) which is the component of the present invention is subjected to the following average composition formula (B-2).

Radiation-curable organopolysiloxane for release sheet by performing the same procedure as in Example 1 except that the viscosity was changed to 100 parts by mass of acrylic group-containing dimethylpolysiloxane having a viscosity at 25 ° C. of 450 mPa · s. Composition 5 was obtained. Using this organopolysiloxane composition 5, the curability test, peeling force test, residual adhesion rate test, and odor measurement described above were performed.

[Example 6]
The same as in Example 5 except that the component corresponding to the component (A), which is the component of the present invention, was changed to 5 parts by mass of the maleimide group-containing organopolysiloxane of the formula (A-2) obtained in Synthesis Example 2. By performing the procedure, a radiation-curable organopolysiloxane composition 6 for a release sheet was obtained. Using this organopolysiloxane composition 6, the curability test, peeling force test, residual adhesive rate test, and odor measurement described above were performed.

[Example 7]
Examples except that the radical polymerization initiator 2-hydroxy-2-methyl-1-phenyl-propane-1-one (C-1) corresponding to the component (C) of the present invention was changed to 0 parts by mass. By performing the same procedure as in No. 5, a radiation-curable organopolysiloxane composition 7 for a release sheet was obtained. Using this organopolysiloxane composition 7, the curability test, peeling force test, residual adhesive rate test, and odor measurement described above were performed.

[Example 8]
Examples except that the radical polymerization initiator 2-hydroxy-2-methyl-1-phenyl-propane-1-one (C-1) corresponding to the component (C) of the present invention was changed to 0 parts by mass. By performing the same procedure as in No. 6, a radiation-curable organopolysiloxane composition 8 for a release sheet was obtained. Using this organopolysiloxane composition 8, the curability test, peeling force test, residual adhesion rate test, and odor measurement described above were performed.

[Comparative Example 1]
The radical polymerization initiator 2-hydroxy-corresponding to the component (C) of the present invention without blending the maleimide group-containing organopolysiloxane of the formula (A-1) corresponding to the component (A) of the present invention. Radiation-curable organopolysiloxane composition for release sheet by performing the same procedure as in Example 1 except that 2-methyl-1-phenyl-propane-1-one (C-1) was changed to 5 parts by mass. I got the thing 9. Using this organopolysiloxane composition 9, the curability test, peeling force test, residual adhesive rate test, and odor measurement described above were performed.

[Comparative Example 2]
The radical polymerization initiator 2-hydroxy-corresponding to the component (C) of the present invention without blending the maleimide group-containing organopolysiloxane of the formula (A-1) corresponding to the component (A) of the present invention. Radiation-curable organopolysiloxane composition for release sheet by performing the same procedure as in Example 5 except that 2-methyl-1-phenyl-propane-1-one (C-1) was changed to 5 parts by mass. I got the thing 10. Using this organopolysiloxane composition 10, the curability test, peeling force test, residual adhesion rate test, and odor measurement described above were performed.

[Comparative Example 3]
Comparative Examples except that the radical polymerization initiator 2-hydroxy-2-methyl-1-phenyl-propane-1-one (C-1) corresponding to the component (C) of the present invention was changed to 0 parts by mass. By performing the same procedure as in No. 1, a radiation-curable organopolysiloxane composition 11 for a release sheet was obtained. The curability test described above was performed using this organopolysiloxane composition 11, but since it did not cure, the peeling force test, the residual adhesion rate test, and the odor measurement were not performed.

[Comparative Example 4]
Comparative Examples except that the radical polymerization initiator 2-hydroxy-2-methyl-1-phenyl-propane-1-one (C-1) corresponding to the component (C) of the present invention was changed to 0 parts by mass. By performing the same procedure as in 2, a radiation-curable organopolysiloxane composition 12 for a release sheet was obtained. The curability test described above was performed using this organopolysiloxane composition 12, but since it did not cure, the peeling force test, the residual adhesion rate test, and the odor measurement were not performed.

[Comparative Example 5]
By performing the same procedure as in Comparative Example 1 except that 2 parts by mass of dimethylpolysiloxane (X) having a viscosity of 3,000 mPa · s at 25 ° C. measured by a B-type viscometer was blended as a light peeling additive. A radiation-curable organopolysiloxane composition 13 for a release sheet was obtained. Using this organopolysiloxane composition 13, the curability test, peeling force test, residual adhesion rate test, and odor measurement described above were performed.

Claims (2)

The following average composition formula (1)

(In the formula, R ¹ is a group selected from an unsubstituted or substituted monovalent hydrocarbon group having the same or different carbon atoms 1 to 10 and an organic group having a maleimide structure represented by the following general formula (2). Yes, at least one of R ¹ contains an organic group having a maleimide structure represented by the following general formula (2). A is an integer of 2 or more, b is an integer of 0 or more, and c is an integer of 0 or more. d is an integer of 0 or more, and 2 ≦ a + b + c + d ≦ 1,000.)

(In the formula, R ² and R ³ are hydrogen atoms that are the same or different from each other, or unsubstituted or substituted monovalent hydrocarbon groups having 1 to 5 carbon atoms, and X is intervening a hetero atom having 1 to 10 carbon atoms. It may be an unsubstituted or substituted divalent hydrocarbon group. The broken line indicates a bond.)
A organopolysiloxane Tona Ru light release additive having a maleimide group represented in,
The following components (B) and (C)
(B) Radical-polymerizable organopolysiloxane containing a (meth) acrylic group represented by the following average composition formula (3): 100 parts by mass.

(In the formula, R ⁴ is a group selected from an unsubstituted or substituted monovalent hydrocarbon group having the same or different carbon atoms 1 to 10, an alkoxy group, a hydroxyl group and an organic group having a (meth) acrylic group. At least one of R ⁴ contains an organic group having a (meth) acrylic group. E is an integer of 2 or more, f is an integer of 0 or more, g is an integer of 0 or more, h is an integer of 0 or more, and 2 ≦ e + f + g + h ≦ 1,000),
(C) Radical polymerization initiator that generates radicals by irradiation with radiation: 0 to 2.5 parts by mass
A light peeling additive for blending a radiation-curable organopolysiloxane composition for a peeling sheet containing. The light peeling additive according to claim 1, wherein 1 to 100 mol% of R ^{1 of the} formula (1) is an organic group having a maleimide structure.