JP2009256542A - Silicone self-adhesive composition with good adhesiveness to substrate and silicone self-adhesive tape - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a silicone self-adhesive composition and a silicone self-adhesive tape using it. <P>SOLUTION: The silicone self-adhesive composition is an addition reaction-curing type silicone self-adhesive composition comprising (A) a linear polysiloxane having two or more alkenyl groups in one molecule and exhibiting viscosity of ≥10,000 mPa s at 25°C, (B) a polysiloxane comprising an R<SP>1</SP><SB>3</SB>SiO<SB>0.5</SB>unit and an SiO<SB>2</SB>unit at a molar ratio, which is a molar ratio of the R<SP>1</SP><SB>3</SB>SiO<SB>0.5</SB>unit to the SiO<SB>2</SB>unit, of 0.6-1.7 (R<SP>1</SP>is a 1-10C monovalent hydrocarbon group), (C) a polysiloxane having two or alkenyl groups in one molecule and exhibiting viscosity of 20-500 mPa s at 25°C, (D) a polysiloxane containing two or more SiH groups in one molecule, (E) a reaction controlling agent, and (F) a platinum catalyst. The self-adhesive tape has a plastic film and a cured product layer of the silicone self-adhesive composition laminated to at least one surface of the plastic film. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a silicone pressure-sensitive adhesive composition, and more particularly to a silicone pressure-sensitive adhesive composition and a silicone pressure-sensitive adhesive tape having performance excellent in substrate adhesion without performing primer treatment.

  Conventionally, a heat-resistant adhesive tape is used which is formed by applying and laminating a silicone adhesive having excellent heat resistance to a plastic film substrate such as a polyester film or a polyimide film. Such a pressure-sensitive adhesive tape is usually wound up in a roll shape, but when it is strongly rewound during use, the silicone pressure-sensitive adhesive layer may be peeled off from the substrate. Further, when the adhesive tape is cut, only the base material is torn, and the silicone pressure-sensitive adhesive layer may be stretched to pull a thread without being cut, or the silicone pressure-sensitive adhesive layer may be lifted from the base material. As described above, the conventional silicone pressure-sensitive adhesive has problems of peeling from the base material and stringing.

  When such an adhesive is used for a pressure-sensitive adhesive tape, there may be a problem, and it is difficult to say that the adhesiveness between the silicone pressure-sensitive adhesive and the plastic film substrate is sufficient. Therefore, in general, after applying a carbon functional silane primer composition as an adhesion improver, the silicone adhesive is treated to improve the adhesion between the film substrate and the silicone adhesive. . However, the substrate adhesion was not satisfactory.

  On the other hand, many primer compositions using organopolysiloxane have been proposed in order to adhere the silicone adhesive to the plastic film. For example, Patent Document 1 discloses a primer composition composed of a diorganopolysiloxane containing a hydroxyl group at both ends of a molecular chain, an organohydrogenpolysiloxane, and an organic carboxylic acid tin salt. Patent Document 2 discloses a hydroxyl group at both ends of a molecular chain. A primer composition comprising a diorganopolysiloxane, an organohydrogenpolysiloxane, a hydrolyzable silyl group-containing vinyl-based and / or acrylic copolymer, and an organic carboxylic acid tin salt has been proposed.

  However, satisfactory adhesion may not be obtained even if any primer composition is used. Furthermore, in order to perform primer treatment, it is necessary to perform adhesive coating after primer treatment. For that purpose, it is necessary to use a special coating device that coats the primer and the adhesive in-line, or to apply the adhesive again to the base material once coated with the primer, All of these are disadvantageous in terms of productivity and cost.

Japanese Patent Publication No.54-44017 JP 6-39584

  The present invention has been made in view of the above circumstances, and provides a silicone pressure-sensitive adhesive composition that does not require primer treatment and has good substrate adhesion only by coating with a silicone pressure-sensitive adhesive, and a silicone pressure-sensitive adhesive tape using the same. For the purpose.

  As a result of intensive studies to achieve the above object, the present inventors have obtained a silicone pressure-sensitive adhesive composition obtained by adding a specific amount of a low-viscosity alkenyl group-containing silicone oil to a silicone pressure-sensitive adhesive composition. In addition, the present inventors have found that the substrate adhesion is excellent and can be suitably used, and the present invention has been made.

That is, the present invention relates to (A) 20 to 80 parts by mass of a linear diorganopolysiloxane having 2 or more alkenyl groups in one molecule and having a viscosity at 25 ° C. of 10,000 mPa · s or more. B) a polyorganosiloxane containing _0.5 units of R ¹ ₃ SiO _0.5 and SiO ₂ units and having a molar ratio of R ¹ ₃ SiO _0.5 units / SiO ₂ units of 0.6 to 1.7 (R ¹ is A monovalent hydrocarbon group having 1 to 10 carbon atoms.) (A) an amount in which the sum of the components (B) is 100 parts by mass (C) having two or more alkenyl groups in one molecule; With respect to a total of 100 parts by mass of the diorganopolysiloxane (A) and the component (B) having an alkenyl group content of 0.015 to 0.15 mol / 100 g and a viscosity at 25 ° C. of 20 to 500 mPa · s. 0.5 to 20 parts by mass (D) Organohydrogenpolysiloxane containing two or more SiH groups in the molecule The molar ratio of SiH groups in component (D) to the sum of alkenyl groups in component (A) and alkenyl groups in component (C) is 0. An amount of 5-20,
(E) Reaction controller (A), (B), (C) and (D) 0 to 8.0 parts by mass with respect to a total of 100 parts by mass, and (F) an effective amount of a platinum-based catalyst. An addition reaction curable silicone pressure-sensitive adhesive composition is provided.
Moreover, this invention provides the adhesive tape characterized by having a plastic film and the hardened | cured material layer of the said silicone adhesive composition laminated | stacked on at least 1 surface of this plastic film.

  The silicone pressure-sensitive adhesive composition of the present invention gives a pressure-sensitive adhesive tape excellent in substrate adhesion performance, and this pressure-sensitive adhesive tape can be suitably used as a heat-resistant silicone tape or an electronic component masking tape.

  The silicone pressure-sensitive adhesive composition having substrate adhesion of the present invention contains a specific amount of a low-viscosity alkenyl group-containing polyorganosiloxane in a conventional silicone pressure-sensitive adhesive composition. The silicone pressure-sensitive adhesive composition of the present invention is an addition reaction curable organopolysiloxane composition.

The silicone pressure-sensitive adhesive composition of the present invention contains components (A) to (F). Hereinafter, the components (A) to (F) will be described in detail.
<(A) component>
Component (A) is a substantially linear diorganopolysiloxane containing two or more alkenyl groups in one molecule, and is preferably one represented by the following formula (1) or (2). .
R ² _(3-a) X _a SiO- (R ² XSiO) _m- (R ² ₂ SiO) _n -SiR ² _(3-a) X _a (1)
R ² ₂ (HO) SiO- (R ² XSiO) _{m + 2-} (R ² ₂ SiO) _n -SiR ² ₂ (OH) (2)
Wherein R ² is independently a monovalent hydrocarbon group not having an aliphatic unsaturated bond, X is independently an alkenyl group-containing monovalent organic group, a is an integer of 0 to 3, preferably 1, m is a number of 0 or more, and n is a number of 100 or more, a and m are not 0 at the same time, and m + n is the viscosity of the polydiorganosiloxane of formula (1) or (2) at 25 ° C. The upper limit of the viscosity is not particularly limited, and is usually at 25 ° C., and is preferably a number that makes 10,000 mPa · s or more, preferably 50,000 mPa · s or more, more preferably 1,000,000 mPa · s or more. (The number may give a raw rubber-like polydiorganosiloxane having no fluidity.)

In the above formula, R ² is preferably a monovalent hydrocarbon group having 1 to 10 carbon atoms, for example, an alkyl group such as a methyl group, an ethyl group, a propyl group or a butyl group; a cycloalkyl group such as a cyclohexyl group An aryl group such as a phenyl group and a tolyl group, and an alkyl group such as a methyl group or a phenyl group is particularly preferable.

  The alkenyl group-containing monovalent organic group represented by X is preferably an organic group having 2 to 10 carbon atoms, such as vinyl group, allyl group, hexenyl group, octenyl group, etc .; acryloylpropyl group, acryloylmethyl group, methacryloylpropyl (Meth) acryloylalkyl groups such as groups; (meth) acryloxyalkyl groups such as acryloxypropyl groups, acryloxymethyl groups, methacryloxypropyl groups, methacryloxymethyl groups; cyclohexenylethyl groups, vinyloxypropyl groups, etc. An alkenyl group-containing monovalent hydrocarbon group is exemplified, and a vinyl group is particularly preferred industrially.

The alkenyl group-containing linear diorganopolysiloxane may be in the form of oil or raw rubber.
The viscosity of the component (A) is preferably 10,000 mPa · s or more, particularly 50,000 mPa · s or more if it is oily at 25 ° C. If it is less than 10,000 mPa · s, crosslinking of the cured product proceeds and the flexibility is impaired, and as a result, the adhesive force may not be exhibited, which is inappropriate. Moreover, if it is a raw rubber-like material (normally, the viscosity at 25 ° C. is 1,000,000 mPa · s or more, particularly 10,000,000 mPa · s or more), toluene is used so that the concentration becomes 30%. The viscosity when dissolved is preferably 100,000 mPa · s or less. If it exceeds 100,000 mPa · s, the composition becomes too viscous and stirring during production becomes difficult. (A) 2 or more types of components may be used together.

  The alkenyl group content of the alkenyl group-containing linear diorganopolysiloxane is 0.0005 to 0.01 mol / 100 g, preferably 0.0005 to 0.007 mol / 100 g, and more preferably 0.001 to 0.00. The range is 005 mol / 100 g. When the alkenyl group content is less than 0.0005 mol / 100 g, the resulting adhesive composition is not sufficiently curable, and when it exceeds 0.01 mol / 100 g, the flexibility of the cured product is reduced, resulting in an adhesive strength. It becomes insufficient.

<(B) component>
The component (B) contains R ¹ ₃ SiO _0.5 units (R ¹ is as described above) and SiO ₂ units, and the molar ratio of R ¹ ₃ SiO _0.5 units / SiO ₂ units is 0.5 to 1. .7, preferably 0.6 to 1.2 polyorganosiloxane. A typical component (B) is substantially composed of only R ¹ ₃ SiO _0.5 units and SiO ₂ units. If the molar ratio of R ¹ ₃ SiO _0.5 unit / SiO ₂ unit is less than 0.5, the adhesive force and tack may be lowered, and if it exceeds 1.7, the adhesive force and holding force may be lowered. An OH group may be contained, and the OH group content is preferably 4.0% by mass or less. When the OH group exceeds 4.0% by mass, the curability of the pressure-sensitive adhesive is lowered, which is not preferable.

(B) 2 or more types of components may be used together. Further, R ¹ SiO _1.5 units and / or R ¹ ₂ SiO units can be contained in the component (B) within a range not impairing the characteristics of the present invention.

(A) component and (B) component may use what was mixed simply, and (A) component is following Formula (2):
R ² ₂ (HO) SiO- (R ² XSiO) _{m + 2-} (R ² ₂ SiO) _n -SiR ² ₂ (OH) (2)
(M and n represent the same number as above, and R ² and X represent the same group as above.)
When the diorganopolysiloxane is contained, the component (A) and the component (B) may be used as a condensation reaction product. In order to perform the condensation reaction, a mixture of the components (A) and (B) dissolved in a solvent such as toluene may be reacted at room temperature or under reflux using an alkaline catalyst.

  The blending mass ratio of the components (A) and (B) may be 20/80 to 80/20, and particularly preferably 30/70 to 70/30. When the blending mass ratio of the polydiorganosiloxane of component (A) is lower than 20/80, the adhesive strength and holding power of the pressure-sensitive adhesive composition are reduced, and when it exceeds 80/20, the adhesive strength and tack are reduced.

<(C) component>
(C) As a 2 or more alkenyl-group containing diorganopolysiloxane in 1 molecule of a component, what is shown by following formula (3) or (4) is preferable.
R ³ _(3-b) Y _b SiO- (R ³ YSiO) _p- (R ³ ₂ SiO) _q -SiR ³ _(3-b) Y _b (3)
R ³ _(3-b) Y _b SiO- (R ³ YSiO) _p- (R ³ ₂ SiO) _q- (R ³ ₁ SiO _1.5 ) _r- (SiR ³ _(3-b) Y _b ) _{r + 1} ( 4)
(Wherein R ³ is each independently a monovalent hydrocarbon group having no aliphatic unsaturated bond, Y is each independently an alkenyl group-containing monovalent organic group, b is an integer of 0 to 3, Preferably, p is a number of 0 or more, q is a number of 3 or more, b and p are not 0 simultaneously, and p + q and p + q + r are represented by the formulas (3) and (4), respectively. The polydiorganosiloxane has a viscosity at 25 ° C. of 20 to 500 mPa · s.)

In the above formula, R ³ is preferably a monovalent hydrocarbon group having 1 to 10 carbon atoms, for example, an alkyl group such as a methyl group, an ethyl group, a propyl group, or a butyl group; a cycloalkyl group such as a cyclohexyl group An aryl group such as a phenyl group and a tolyl group; an alkyl group such as a methyl group or a phenyl group is particularly preferable.

  The alkenyl group-containing monovalent organic group represented by Y is preferably one having 2 to 10 carbon atoms, alkenyl groups such as vinyl group, allyl group, hexenyl group, octenyl group; acryloylpropyl group, acryloylmethyl group, methacryloylpropyl group. (Meth) acryloylalkyl group such as; (meth) acryloxyalkyl group such as acryloxypropyl group, acryloxymethyl group, methacryloxypropyl group, methacryloxymethyl group; alkenyl such as cyclohexenylethyl group, vinyloxypropyl group Examples thereof include a group-containing monovalent hydrocarbon group, and a vinyl group is particularly preferred industrially.

  The viscosity of component (C) at 25 ° C. is preferably 20 mPa · s to 500 mPa · s, more preferably 40 to 500 mPa · s, and particularly preferably 100 to 500 mPa · s. If it exceeds 500 mPa · s, the adhesiveness of the pressure-sensitive adhesive composition will be insufficient, and if it is less than 20 mPa · s, the flexibility of the cured product will decrease and the adhesiveness and adhesiveness will decrease. (C) 2 or more types may be used together.

  The alkenyl group content of the low viscosity alkenyl group-containing diorganopolysiloxane is 0.015 to 0.15 mol / 100 g (component (C)), preferably 0.015 to 0.08 mol / 100 g, Preferably it is the range of 0.02-0.08 mol / 100g. When the alkenyl group content is less than 0.015 mol / 100 g, the adhesiveness of the pressure-sensitive adhesive composition is not sufficiently improved, and when it exceeds 0.15 mol / 100 g, the flexibility of the cured product decreases, Adhesion is insufficient.

  The alkenyl group-containing diorganopolysiloxane may be linear or branched.

  The alkenyl group of the alkenyl group-containing diorganopolysiloxane may be at the end of the molecular chain or only within the molecular chain, but preferably the end of the molecular chain is blocked with an alkenyl group. This is because the molecular chain terminal alkenyl group is highly reactive and can complete the reaction in a short time.

  The amount of component (C) added is preferably 0.5 to 20 parts by mass, more preferably 2 to 10 parts by mass, and particularly preferably 5 to 10 parts by mass with respect to 100 parts by mass of the mixture of components (A) and (B). Part by mass. If the amount is 0.5 parts by mass or less, sufficient adhesiveness cannot be obtained in the pressure-sensitive adhesive composition.

(C) component is other (A), (B), (D), (F) at the time of manufacture of a silicone adhesive composition.
You may add with a component and (E) component as needed, and may add with the crosslinking agent component (D) to the existing addition reaction hardening type silicone adhesive composition marketed.

<(D) component>
Component (D) is a crosslinking agent, and is an organohydrogenpolysiloxane having at least 2, preferably 3 or more hydrogen atoms (SiH groups) bonded to silicon atoms in one molecule. Linear, branched or cyclic ones can be used.
(D) As a component, although the thing of following formula (5) and (6) can be illustrated, it is not limited to these.

（式中、Ｒ^４は夫々独立して炭素原子数１から１０の１価炭化水素基、ｃは０または１であり、ｘ及びｙは整数であり、２ｃ＋ｘ≧２、かつｘ＋ｙは式（５）のオルガノハイドロジェンポリシロキサンの２５℃における粘度が１〜５，０００ｍＰａ・ｓとなる数を示し、好ましくはｘ＋ｙ≧４、更に好ましくは２００≧ｘ＋ｙ≧８の整数を示す。ｓは２以上の整数、ｔは０以上の整数で、かつｓ＋ｔ≧３、好ましくは８≧ｓ＋ｔ≧３の整数を示す。）

(Wherein R ⁴ is each independently a monovalent hydrocarbon group having 1 to 10 carbon atoms, c is 0 or 1, x and y are integers, 2c + x ≧ 2, and x + y is a formula (5 ) Of the organohydrogenpolysiloxane has a viscosity at 25 ° C. of 1 to 5,000 mPa · s, preferably x + y ≧ 4, more preferably 200 ≧ x + y ≧ 8, where s is 2 or more. An integer, t is an integer of 0 or more, and s + t ≧ 3, preferably 8 ≧ s + t ≧ 3.

  The viscosity of the organohydrogenpolysiloxane of component (D) at 25 ° C. is preferably 1 to 5,000 mPa · s, and more preferably 5 to 500 mPa · s. The organohydrogenpolysiloxane may be a mixture of two or more.

  The amount of component (D) used is such that the molar ratio of SiH groups in component (D) to the total amount of alkenyl groups in component (A) and the amount of alkenyl groups in component (C) (SiH groups / alkenyl groups). It is preferable to blend so as to be in the range of 0.5 to 20, particularly 2.0 to 10.0. If the molar ratio of SiH group to alkenyl group is less than 0.5, the crosslinking density is low, and the pressure-sensitive adhesive layer may not be cured accordingly, and if it exceeds 20, the crosslinking density becomes too high and sufficient adhesive strength is obtained. And tack may not be obtained. If the molar ratio exceeds 20, the usable time of the treatment liquid may be shortened.

<(E) component>
Component (E) is a reaction control agent and is necessary to prevent the treatment liquid from thickening or gelling before heat-curing when the silicone pressure-sensitive adhesive composition is prepared or applied to the substrate. It is optionally added depending on the case. Specific examples include 3-methyl-1-butyn-3-ol, 3-methyl-1-pentyn-3-ol, 3,5-dimethyl-1-hexyn-3-ol, 1-ethynylcyclohexanol, 3 -Methyl-3-trimethylsiloxy-1-butyne, 3-methyl-3-trimethylsiloxy-1-pentyne, 3,5-dimethyl-3-trimethylsiloxy-1-hexyne, 1-ethynyl-1-trimethylsiloxycyclohexane, Bis (2,2-dimethyl-3-butynoxy) dimethylsilane, 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane, 1,1,3,3-tetramethyl -1,3-divinyldisiloxane and the like, 1-ethynylcyclohexanol and 3-methyl-1-butyn-3-ol are preferred A.

  (E) The compounding quantity of a component should just be the range of 0-8.0 mass parts with respect to a total of 100 mass parts of (A), (B), (C), and (D) component normally, Preferably It is preferable that it is 0.01-8.0 mass parts, especially 0.05-2.0 mass parts. If it exceeds 8.0 parts by mass, the curability of the silicone pressure-sensitive adhesive composition may decrease. If it is 0.01 part by mass or more, the effect of reaction control is sufficiently exhibited.

<(F) component>
Component (F) is a platinum-based catalyst (that is, a platinum group metal catalyst), such as chloroplatinic acid, an alcohol solution of chloroplatinic acid, a reaction product of chloroplatinic acid and an alcohol, and a reaction product of chloroplatinic acid and an olefin compound. And a reaction product of chloroplatinic acid and a vinyl group-containing siloxane.

  The amount of component (F) added is an effective amount, usually 1 to 5,000 ppm as platinum content (in terms of mass) with respect to the sum of components (A), (B), (C) and (D), It is preferably 5 to 2,000 ppm. If it is less than 1 ppm, the curability of the silicone pressure-sensitive adhesive composition is lowered, the crosslinking density is lowered and the holding power may be lowered. If it exceeds 5,000 ppm, the usable time of the treatment bath may be shortened.

  In addition, you may add and use the mixture of (C) component and (D) component to a commercially available addition reaction hardening type silicone adhesive composition. In this case, it is preferable that the molar ratio of the SiH group in the component (D) to the amount of the alkenyl group in the component (C) is 0.5 to 5, particularly 1 to 4. If the molar ratio of the alkenyl group and SiH group is less than 0.5, the crosslinking density is low, and the pressure-sensitive adhesive layer may not be cured accordingly. If it exceeds 5, the crosslinking density becomes too high, and sufficient adhesive strength and Tack may not be obtained. On the other hand, if it exceeds 5, the usable time of the treatment liquid may be shortened. Furthermore, (E) component can also be added arbitrarily.

<Optional component>
In addition to the above components, optional components can be added to the silicone pressure-sensitive adhesive composition of the present invention. For example, non-reactive polyorganosiloxanes such as polydimethylsiloxane and polydimethyldiphenylsiloxane; antioxidants such as phenol, quinone, amine, phosphorus, phosphite, sulfur and thioether; triazole, Light stabilizers such as benzophenone series; flame retardants such as phosphate ester series, halogen series, phosphorus series, antimony series; antistatic agents such as cationic activator, anionic activator, nonionic activator; As solvents for lowering viscosity, aromatic solvents such as toluene and xylene, aliphatic solvents such as hexane, octane and isoparaffin, ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone, and ester solvents such as ethyl acetate and isobutyl acetate Solvent, diisopropyl ether, 1,4-dioxane Ether solvents, or and mixtures of these solvents are used for.

<Base material>
The silicone pressure-sensitive adhesive composition formulated as described above can be applied to various substrates and cured under predetermined conditions to obtain a pressure-sensitive adhesive layer.
As a base material, plastic films such as polyester, polytetrafluoroethylene, polyimide, polyphenylene sulfide, polyamide, polycarbonate, polystyrene, polypropylene, polyethylene, polyvinyl chloride; metal foil such as aluminum foil and copper foil; Japanese paper, synthetic paper, Paper such as polyethylene laminated paper; cloth; glass fiber; and a composite base material formed by laminating a plurality of these.

  In order to further improve the adhesion between these substrates and the pressure-sensitive adhesive layer, a primer-treated, corona-treated, etching-treated, or plasma-treated substrate can be optionally used.

The coating method may be applied using a known coating method, comma coater, lip coater, roll coater, die coater, knife coater, blade coater, rod coater, kiss coater, gravure coater, screen coating, dipping. Examples thereof include coating and cast coating.
The coating amount is preferably such an amount that the thickness of the pressure-sensitive adhesive layer after curing is 2 to 200 μm, particularly 3 to 100 μm.

  The curing conditions are usually 80 to 130 ° C. for 30 seconds to 3 minutes, but are not limited thereto.

  As described above, the silicone pressure-sensitive adhesive composition of the present invention may be directly applied to a substrate to produce an adhesive tape, or it may be applied to a release film or release paper that has been subjected to release coating, and then cured. Then, you may manufacture an adhesive tape with the transfer method bonded together to said base material.

  Although it does not specifically limit as an adherend by the adhesive tape manufactured using the silicone adhesive composition of this invention, The following can be illustrated: Metals, such as stainless steel, copper, iron; These treated metals; ceramics such as glass and ceramics; resins such as polytetrafluoroethylene, polyimide, epoxy resin, and novolac resin; and a composite formed by combining a plurality of these metals.

  EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated concretely, this invention is not restrict | limited to the following Example. In addition, the part in an example shows a mass part,% shows the mass%, and a characteristic value shows the measured value by the following test method. Me represents a methyl group and Vi represents a vinyl group.

Adhesive force After applying the addition reaction curable silicone pressure-sensitive adhesive composition solution to a polyimide film having a thickness of 25 μm and a width of 25 mm using an applicator so that the thickness after curing is 30 μm, conditions of 130 ° C. for 1 minute And cured by heating to prepare an adhesive tape.
The pressure-sensitive adhesive tape was affixed to a stainless steel plate and pressed by reciprocating a roller covered with a rubber layer having a weight of 2 kg. After leaving at room temperature for about 20 hours, peel off the end of the adhesive tape a little and grip it, and peel off the adhesive tape from the stainless steel plate at a speed of 300 mm / min in the direction of an angle of 180 °. The minimum force required (N / 25 mm) was measured.

Base material adhesion The adhesive tape was created with the preparation method similar to the adhesive tape used for the measurement of adhesive force. Peeling of the adhesive layer of the adhesive tape from the substrate is performed in a state in which a 2 mm cut is made on the side of the 25 mm width of the film substrate and then the both sides of the adhesive tape are pulled to separate the film substrate into two. Further, pull from both sides to check whether the adhesive layer is lifted from the film base (hereinafter referred to as “peel”). The results are shown in Table 1, and the adhesive tape with the adhesive lifted over the entire surface is partially lifted. Were marked with Δ, and those with no lift were marked with ○.
Furthermore, the cut-off property is cut only in the base film as in the above, and the adhesive tape (the laminate) is pulled to the left and right, and the adhesive layer is pulled to the left and right at the location above the cut to extend. The amount of elongation (mm, hereinafter referred to as “elongation”) of the pressure-sensitive adhesive layer until it was cut at a certain point was measured. If the adhesiveness is good, the elongation of the adhesive is shortened.

[Example 1]
When dissolved in toluene to a concentration of 30%, the viscosity at 25 ° C. is 27,000 mPa · s, has 0.0015 mol / 100 g of methylvinylsiloxane units, and both ends of the molecular chain are SiMe _2. Polysiloxane containing vinyl group blocked with Vi group (40 parts), polysiloxane comprising Me ₃ SiO _0.5 unit and SiO ₂ unit (Me ₃ SiO _0.5 unit / SiO ₂ unit = 0.80) A solution consisting of a 60% toluene solution (100 parts) and toluene (26.7 parts) was sealed at both ends of the molecular chain with SiMe ₂ Vi groups, the viscosity at 25 ° C. was 60 mPa · s, and the vinyl group content 5 parts by weight of a linear polydimethylsiloxane oil having a ratio of 0.065 mol / 100 g, a crosslinking agent of the following formula (0.97 parts, SiH group: silicon bond in the composition The molar ratio of i group 2.5), and ethinyl cyclohexanol (0.1 parts) was added and mixed.
Me ₃ SiO— [MeHSiO] ₄₀ —SiMe ₃

  To the above mixture (100 parts), toluene (50 parts) and a platinum-based catalyst were added in an amount of 40 ppm (platinum conversion, the same applies hereinafter) with respect to the total of the siloxane components in the mixture, and further mixed to obtain a siloxane content. About 40% silicone adhesive composition solution was prepared. The adhesive strength and substrate adhesion of this silicone pressure-sensitive adhesive composition were measured. The results are shown in Table 1.

[Example 2]
When dissolved in toluene to a concentration of 30%, the viscosity at 25 ° C. is 27,000 mPa · s, has 0.0015 mol / 100 g of methylvinylsiloxane units, and both ends of the molecular chain are SiMe _2. Polysiloxane containing vinyl group blocked with Vi group (40 parts), polysiloxane comprising Me ₃ SiO _0.5 unit and SiO ₂ unit (Me ₃ SiO _0.5 unit / SiO ₂ unit = 0.80) In a solution consisting of 60% toluene solution (100 parts) and toluene (26.7 parts), both molecular chain ends are blocked with SiMe ₂ Vi groups, viscosity at 25 ° C. is 400 mPa · s, vinyl group content 5 parts by weight of a linear polydimethylsiloxane oil having a ratio of 0.018 mol / 100 g, a crosslinking agent of the following formula (0.69 parts, SiH group: silicon bond in the composition) The molar ratio of Vi group 4.6), and ethinyl cyclohexanol (0.1 parts) was added and mixed.
Me ₃ SiO— [MeHSiO] ₄₀ —SiMe ₃

  To the mixture (100 parts), toluene (50 parts) and a platinum-based catalyst are added in an amount of 40 ppm based on the total amount of siloxane components in the mixture, and further mixed to form a silicone adhesive composition having a siloxane content of about 40%. A product solution was prepared. The adhesive strength and substrate adhesion of this silicone pressure-sensitive adhesive composition were measured. The results are shown in Table 1.

[Example 3]
When dissolved in toluene to a concentration of 30%, the viscosity at 25 ° C. is 27,000 mPa · s, has 0.0015 mol / 100 g of methylvinylsiloxane units, and both ends of the molecular chain are SiMe _2. Polysiloxane containing vinyl group blocked with Vi group (40 parts), polysiloxane comprising Me ₃ SiO _0.5 unit and SiO ₂ unit (Me ₃ SiO _0.5 unit / SiO ₂ unit = 0.80) In a solution consisting of 60% toluene solution (100 parts) and toluene (26.7 parts), both molecular chain ends are blocked with SiMe ₂ Vi groups, viscosity at 25 ° C. is 200 mPa · s, vinyl group content 5 parts by weight of a branched polydimethylsiloxane oil having a ratio of 0.070 mol / 100 g, a crosslinking agent of the following formula (1.00 part, SiH group: silicon bond in the composition The molar ratio of i group 2.4), and ethinyl cyclohexanol (0.1 parts) was added and mixed.
Me ₃ SiO— [MeHSiO] ₄₀ —SiMe ₃

  To the mixture (100 parts), toluene (50 parts) and a platinum-based catalyst are added in an amount of 40 ppm based on the total amount of siloxane components in the mixture, and further mixed to form a silicone adhesive composition having a siloxane content of about 40%. A product solution was prepared. The adhesive strength and substrate adhesion of this silicone pressure-sensitive adhesive composition were measured. The results are shown in Table 1.

[Comparative Example 1]
When dissolved in toluene to a concentration of 30%, the viscosity at 25 ° C. is 27,000 mPa · s, has 0.0015 mol / 100 g of methylvinylsiloxane units, and the molecular chain terminal is SiMe ₂ Vi. 60 of polysiloxane (Me ₃ SiO _0.5 unit / SiO ₂ unit = 0.80) comprising vinyl group-containing polydimethylsiloxane blocked with a group (40 parts), Me ₃ SiO _0.5 unit and SiO ₂ unit % Toluene solution (100 parts) and toluene (26.7 parts) in a solution of the following formula cross-linking agent (0.58 parts, SiH groups: molar ratio of silicon-bonded Vi groups in the composition 9.7) , And ethynylcyclohexanol (0.1 parts) were added and mixed.
Me ₃ SiO— [MeHSiO] ₄₀ —SiMe ₃

  To the mixture (100 parts), toluene (50 parts) and a platinum-based catalyst are added in an amount of 40 ppm based on the total amount of siloxane components in the mixture, and further mixed to form a silicone adhesive composition having a siloxane content of about 40%. A product solution was prepared. The adhesive strength and substrate adhesion of this silicone pressure-sensitive adhesive composition were measured. The results are shown in Table 1.

[Comparative Example 2]
When dissolved in toluene to a concentration of 30%, the viscosity at 25 ° C. is 27,000 mPa · s, has 0.0015 mol / 100 g of methylvinylsiloxane units, and both ends of the molecular chain are SiMe _2. Polysiloxane containing vinyl group blocked with Vi group (40 parts), polysiloxane comprising Me ₃ SiO _0.5 unit and SiO ₂ unit (Me ₃ SiO _0.5 unit / SiO ₂ unit = 0.80) A solution consisting of a 60% toluene solution (100 parts) and toluene (26.7 parts) was sealed at both ends of the molecular chain with SiMe ₂ Vi groups, the viscosity at 25 ° C. was 10 mPa · s, and the vinyl group content 5 parts by weight of a linear polydimethylsiloxane oil having a ratio of 0.25 mol / 100 g, a crosslinking agent of the following formula (1.91 parts, SiH group: silicon-bonded Vi in the composition Molar ratio 1.5), and ethynyl cyclohexanol (0.1 parts) was added and mixed.
Me ₃ SiO— [MeHSiO] ₄₀ —SiMe ₃

  To the mixture (100 parts), toluene (50 parts) and a platinum-based catalyst are added in an amount of 40 ppm based on the total amount of siloxane components in the mixture, and further mixed to form a silicone adhesive composition having a siloxane content of about 40%. A product solution was prepared. The adhesive strength and substrate adhesion of this silicone pressure-sensitive adhesive composition were measured. The results are shown in Table 1.

[Comparative Example 3]
When dissolved in toluene to a concentration of 30%, the viscosity at 25 ° C. is 27,000 mPa · s, has 0.0015 mol / 100 g of methylvinylsiloxane units, and both ends of the molecular chain are SiMe _2. Polysiloxane containing vinyl group blocked with Vi group (40 parts), polysiloxane comprising Me ₃ SiO _0.5 unit and SiO ₂ unit (Me ₃ SiO _0.5 unit / SiO ₂ unit = 0.80) A solution consisting of a 60% toluene solution (100 parts) and toluene (26.7 parts) was sealed at both ends of the molecular chain with SiMe ₂ Vi groups, and had a viscosity of 1000 mPa · s at 25 ° C. and a vinyl group content. 5 parts by mass of a linear polydimethylsiloxane oil of 0.013 mol / 100 g, a crosslinking agent of the following formula (0.46 parts, SiH group: silicon bond in the composition The molar ratio of i group 3.7), and ethinyl cyclohexanol (0.1 parts) was added and mixed.
Me ₃ SiO— [MeHSiO] ₄₀ —SiMe ₃

  To the mixture (100 parts), toluene (50 parts) and a platinum-based catalyst are added in an amount of 40 ppm based on the total amount of siloxane components in the mixture, and further mixed to form a silicone adhesive composition having a siloxane content of about 40%. A product solution was prepared. The adhesive strength and substrate adhesion of this silicone pressure-sensitive adhesive composition were measured. The results are shown in Table 1.

[Comparative Example 4]
When dissolved in toluene to a concentration of 30%, the viscosity at 25 ° C. is 27,000 mPa · s, has 0.0015 mol / 100 g of methylvinylsiloxane units, and both ends of the molecular chain are SiMe _2. Polysiloxane containing vinyl group blocked with Vi group (40 parts), polysiloxane comprising Me ₃ SiO _0.5 unit and SiO ₂ unit (Me ₃ SiO _0.5 unit / SiO ₂ unit = 0.80) A solution consisting of 60% toluene solution (100 parts) and toluene (26.7 parts) was sealed at both ends of the molecular chain with SiMe ₂ Vi groups, and had a viscosity of 300 mPa · s at 25 ° C. and a vinyl group content. 5 parts by mass of a branched polydimethylsiloxane oil of 0.18 mol / 100 g, a crosslinking agent of the following formula (1.67 parts, SiH group: silicon-bonded Vi in the composition Molar ratio 1.7), and ethynyl cyclohexanol (0.1 parts) was added and mixed.
Me ₃ SiO— [MeHSiO] ₄₀ —SiMe ₃

  To the above mixture (100 parts), toluene (50 parts) and a platinum-based catalyst were added in an amount of 40 ppm (platinum conversion, the same applies hereinafter) with respect to the total of the siloxane components in the mixture, and further mixed to obtain a siloxane content. About 40% silicone adhesive composition solution was prepared. The adhesive strength and substrate adhesion of this silicone pressure-sensitive adhesive composition were measured. The results are shown in Table 1.

[Example 4]
When dissolved in toluene to a concentration of 30%, the viscosity at 25 ° C. is 27,000 mPa · s, has 0.0015 mol / 100 g of methylvinylsiloxane units, and both ends of the molecular chain are SiMe _2. Polysiloxane containing vinyl group blocked with Vi group (40 parts), polysiloxane comprising Me ₃ SiO _0.5 unit and SiO ₂ unit (Me ₃ SiO _0.5 unit / SiO ₂ unit = 0.80) In a solution consisting of 60% toluene solution (100 parts) and toluene (26.7 parts), both molecular chain ends are blocked with SiMe ₂ Vi groups, viscosity at 25 ° C. is 400 mPa · s, vinyl group content 0.58 parts by weight of a linear polydimethylsiloxane oil having a ratio of 0.018 mol / 100 g, a crosslinking agent of the following formula (0.59 parts, SiH group: silicon in the composition) The molar ratio of coupling Vi group 3.9), and ethinyl cyclohexanol (0.1 parts) was added and mixed.
Me ₃ SiO— [MeHSiO] ₄₀ —SiMe ₃

  To the mixture (100 parts), toluene (50 parts) and a platinum-based catalyst are added in an amount of 40 ppm based on the total amount of siloxane components in the mixture, and further mixed to form a silicone adhesive composition having a siloxane content of about 40%. A product solution was prepared. The adhesive strength and substrate adhesion of this silicone pressure-sensitive adhesive composition were measured. The results are shown in Table 1.

[Example 5]
When dissolved in toluene to a concentration of 30%, the viscosity at 25 ° C. is 27,000 mPa · s, has 0.0015 mol / 100 g of methylvinylsiloxane units, and both ends of the molecular chain are SiMe _2. Polysiloxane containing vinyl group blocked with Vi group (40 parts), polysiloxane comprising Me ₃ SiO _0.5 unit and SiO ₂ unit (Me ₃ SiO _0.5 unit / SiO ₂ unit = 0.80) In a solution consisting of 60% toluene solution (100 parts) and toluene (26.7 parts), both molecular chain ends are blocked with SiMe ₂ Vi groups, viscosity at 25 ° C. is 400 mPa · s, vinyl group content 20 parts by mass of a linear polydimethylsiloxane oil having a ratio of 0.018 mol / 100 g, a crosslinking agent of the following formula (1.02 parts, SiH group: silicon bond in the composition) The molar ratio of Vi group 2.4), and ethinyl cyclohexanol (0.1 parts) was added and mixed.
Me ₃ SiO— [MeHSiO] ₄₀ —SiMe ₃

  To the mixture (100 parts), toluene (50 parts) and a platinum-based catalyst are added in an amount of 40 ppm based on the total amount of siloxane components in the mixture, and further mixed to form a silicone adhesive composition having a siloxane content of about 40%. A product solution was prepared. The adhesive strength and substrate adhesion of this silicone pressure-sensitive adhesive composition were measured. The results are shown in Table 1.

[Comparative Example 5]
When dissolved in toluene to a concentration of 30%, the viscosity at 25 ° C. is 27,000 mPa · s, has 0.0015 mol / 100 g of methylvinylsiloxane units, and both ends of the molecular chain are SiMe _2. Polysiloxane containing vinyl group blocked with Vi group (40 parts), polysiloxane comprising Me ₃ SiO _0.5 unit and SiO ₂ unit (Me ₃ SiO _0.5 unit / SiO ₂ unit = 0.80) In a solution consisting of 60% toluene solution (100 parts) and toluene (26.7 parts), both molecular chain ends are blocked with SiMe ₂ Vi groups, viscosity at 25 ° C. is 400 mPa · s, vinyl group content 30 parts by mass of a linear polydimethylsiloxane oil having a ratio of 0.018 mol / 100 g, a crosslinking agent of the following formula (1.23 parts, SiH group: silicon bond in the composition) The molar ratio of Vi group 2.1), and ethinyl cyclohexanol (0.1 parts) was added and mixed.
Me ₃ SiO— [MeHSiO] ₄₀ —SiMe ₃

  To the mixture (100 parts), toluene (50 parts) and a platinum catalyst are added in an amount of 40 ppm based on the total amount of siloxane components in the mixture, and further mixed, and a silicone pressure-sensitive adhesive composition having a siloxane content of about 40%. A solution was prepared. The adhesive strength and substrate adhesion of this silicone pressure-sensitive adhesive composition were measured. The results are shown in Table 1.

Claims (4)

(A) 20-80 parts by mass of a linear diorganopolysiloxane having two or more alkenyl groups in one molecule and a viscosity at 25 ° C. of 10,000 mPa · s or more (B) R ¹ ₃ SiO A polyorganosiloxane containing _0.5 units and SiO ₂ units and having a molar ratio of R ¹ ₃ SiO _0.5 units / SiO ₂ units of 0.6 to 1.7 (R ¹ is from 1 to 10 carbon atoms) (A) The amount that the sum of the components (A) and (B) is 100 parts by mass. (C) The molecule has two or more alkenyl groups, and the alkenyl group content is 0. The diorganopolysiloxane (A) and the component (B) having a viscosity at 25 ° C. of 20 to 500 mPa · s are 0.5 to 20 with respect to a total of 100 parts by mass. Mass part (D) 2 or more in one molecule SiH group-containing organohydrogenpolysiloxane (A) The molar ratio of SiH groups in component (D) to the sum of alkenyl groups in component (A) and alkenyl groups in component (C) is 0.5-20. amount,
(E) Reaction controller (A), (B), (C) and (D) 0 to 8.0 parts by mass with respect to a total of 100 parts by mass, and (F) an effective amount of a platinum-based catalyst. Addition reaction curable silicone pressure-sensitive adhesive composition.   The silicone pressure-sensitive adhesive composition according to claim 1, wherein both ends of the (C) component diorganopolysiloxane are blocked with alkenyl groups.   The blending amount of the reaction control agent of the component (E) is 0.01 to 8.0 parts by mass with respect to a total of 100 parts by mass of the components (A), (B), (C) and (D). The silicone pressure-sensitive adhesive composition according to claim 1 or 2, characterized in that   A pressure-sensitive adhesive tape comprising: a plastic film; and a cured product layer of the silicone pressure-sensitive adhesive composition according to claim 1 laminated on at least one surface of the plastic film.