KR101225391B1 - Addition-Curable Silicone Rubber Composition and Cohesive Rubber Sheet - Google Patents

Abstract

The present invention provides an addition-curable silicone rubber composition which is excellent in moldability, has a surface adhesiveness, suitable rubber hardness and rubber strength, and provides a cured product having heat resistance, and an adhesive rubber sheet formed by curing the composition.

The adhesive rubber sheet of this invention is organopolysiloxane containing two or more silicon atom-bonded alkenyl groups in (A) 1 molecule,

_{(B) R 3 SiO 1/} 2 units (R is a monovalent hydrocarbon group) and composed mainly of SiO ₂ units, the mole ratio _{[R 3 SiO 1/2 / SiO 2} ] is 0.5 to 1.5, the total amount of R 0 to Resinous copolymer which is 0.0001 mol / g,

(C) organohydrogenpolysiloxane containing two or more Si-H groups in one molecule,

(D) fine powder silica,

(E) heat resistance imparting agent,

(F) addition reaction catalyst

Containing a hardened | cured material, and hardened | cured by this addition-curable silicone rubber composition which has surface adhesiveness.

Silicone rubber composition, adhesive rubber sheet, resinous copolymer

Description

Addition-Curable Silicone Rubber Composition and Cohesive Rubber Sheet

[Patent Document 1] Japanese Unexamined Patent Publication No. 2002-170788

[Patent Document 2] Japanese Patent Application Laid-Open No. 54-37907

[Patent Document 3] Japanese Unexamined Patent Publication No. 63-22886

[Patent Document 4] Japanese Patent Application Laid-Open No. 2004-189945

[Patent Document 5] Japanese Unexamined Patent Publication No. 2004-190013

The present invention relates to an addition-curable silicone rubber composition that provides adhesion, and more particularly, to an addition-curable silicone rubber composition and a composition which provides a rubber sheet having a low drop in adhesion even when the rubber sheet after curing is exposed to high temperature. It relates to an adhesive rubber sheet formed.

BACKGROUND OF THE INVENTION Rubber sheets are conventionally used as fixing sheets for various parts and tools, for example, for fixing medical instruments in hospitals and the like and for fixing tableware in restaurants and party halls. Moreover, it is used as a conveyance sheet in the assembly process of various micro components and flake components using the adhesive force. In particular, the adhesive rubber sheet having excellent heat resistance can be used in a process requiring heating such as adhesive curing, cleaning, solder reflow, and the like. Therefore, the adhesive rubber sheet can be used for applications that cannot be used with ordinary adhesives. For example, it is used as a use which fixes and conveys these components in manufacturing processes, such as a capacitor | condenser, an actuator, an inductor. Or it is used for the process of manufacturing an electronic device which has the process of mounting an electronic component etc. on the surface of a thin board printed wiring board including a flexible printed wiring board, and the process of mounting the said printed wiring board in an electronic device. Japanese Laid-Open Patent Publication No. 2002-170788 (Patent Document 1) exemplifies a silicone adhesive material used in such a step, but no specific composition of the silicone is recorded.

The pressure-sensitive adhesive is also called a pressure-sensitive adhesive, and has a property of easily adhering to the surface of an object at a pressure as small as a finger press. Such an adhesive is used for adhesive products, such as a cellophane tape, an electrical insulation vinyl tape, a masking tape, and an adhesive sheet, for example. As an adhesive used for these adhesive tapes and sheets, what has a main component containing natural rubber, synthetic rubber, etc. is used, but these adhesive compositions are easy to deteriorate by heat, light, etc., but there exists a problem that adhesiveness falls at low temperature. On the other hand, silicone adhesives have excellent heat resistance, cold resistance, and electrical properties peculiar to silicone, and can be adhesive without impairing their properties, and therefore, they are widely used in various adhesive products requiring high reliability.

These silicone pressure-sensitive adhesive include (CH _{3) 3} SiO _{0 .5} units and SiO ₂ containing silicon adhesive, or an alkenyl group containing a condensation product of a polysiloxane and dimethyl silicone raw rubber having a unit of an organopolysiloxane and organopolysiloxane hydrochloride of hydroxyl hydrogen polysiloxane silyl Additive silicone pressure-sensitive adhesives (see Patent Documents 2 and 3) by a polymerization reaction are known. However, these adhesives mainly form a thin film by coating and use the adhesiveness of the surface, and there is no mention of rubber hardness or strength at all. In practice, even when these compositions are used as rubber sheets, the adhesive force is sufficient, but they are not suitable for the manufacturing process of the fixed sheet of the jig or the electronic components used repeatedly because they do not have rubber strength. In particular, since the adhesive material used for the manufacturing line of various electronic components has a heating process, it is preferable to use the silicone rubber with favorable heat resistance. However, in these manufacturing lines, it may become 250 degreeC or more in the solder reflow process etc., for example, and heat resistance is required further.

Japanese Patent Laid-Open No. 2004-189945 (Patent Document 4) discloses a high-strength silicone rubber adhesive material, but there is no description of heat resistance, and there are no examples in which a heat imparting agent is specifically added. Moreover, although Unexamined-Japanese-Patent No. 2004-190013 (patent document 5) exemplifies adding a hindered amine as a heat resistance imparting agent, since the amine compound becomes a catalyst poison of hydrosilylation, which is a crosslinking reaction of silicone rubber, It was not preferable and it could not be used especially for shaping | molding in a short time.

This invention is made | formed in view of the said situation, Since it is excellent in moldability, has surface adhesiveness, and has suitable rubber hardness and rubber strength, the sheet | seat for adhesive fixation of the said electronic component in the manufacturing line of the electronic component used repeatedly. It is an object of the present invention to provide an addition-curable silicone rubber composition which can be preferably used as a curing agent and has a heat resistance, which provides a cured product that can withstand heating processes such as solder reflow, and an adhesive rubber sheet formed by curing the composition. .

MEANS TO SOLVE THE PROBLEM As a result of earnestly examining in order to achieve the said objective, when this is made into the addition-curable silicone rubber composition containing the following (A)-(D) component, it is excellent in moldability, and the hardened | cured material of this composition has surface adhesiveness. Since it has a suitable rubber hardness and rubber strength, it can be preferably used as an adhesive fixing sheet in a production line for electronic parts used repeatedly, and because it has heat resistance, it can withstand heating processes such as solder reflow. The present invention has been found to be an adhesive rubber sheet.

Therefore,

(A) 30 to 95 parts by mass of an organopolysiloxane containing an alkenyl group bonded to two or more silicon atoms in one molecule,

(B) R ₃ SiO _1/2 units (wherein, R is an unsubstituted or substituted monovalent hydrocarbon group) and composed mainly of SiO ₂ units, R ₃ SiO _{1 /} mole ratio of ₂ units and SiO _{2 units,} [R ₃ SiO _1/2 / SiO ₂ ] is 0.5 to 1.5, and 5 to 70 parts by mass of the resinous copolymer having a total amount of 0.0001 mol / g or less even if R contains or does not contain an alkenyl group ((A) , (B) the sum total of 100 parts by mass),

(C) 0.2 to 30 parts by mass of an organohydrogenpolysiloxane containing a hydrogen atom bonded to two or more silicon atoms in one molecule,

(D) 1 to 200 parts by mass of fine powder silica,

(E) 0.05-50 parts by mass of heat resistance imparting agent,

(F) catalytic amount addition reaction catalyst

It contains, and the hardened | cured material has surface adhesiveness, The addition-curable silicone rubber composition and the adhesive rubber sheet which harden this composition are provided.

BEST MODE FOR CARRYING OUT THE INVENTION [

Component (A) of the addition-curable silicone rubber composition of the present invention is an organopolysiloxane containing an alkenyl group bonded to two or more silicon atoms in one molecule, and as the organopolysiloxane of this component (A), the following average formula (1) Can be used as indicated.

R ¹ _a SiO _{(4-a) / 2}

Wherein R ¹ is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms, preferably 1 to 8 carbon atoms, wherein at least two of R ¹ are alkenyl groups and a is 1.5 to 2.8, preferably 1.8 to 2.5, more preferably in the range of 1.95 to 2.05.

Here, as the unsubstituted or substituted monovalent hydrocarbon group bonded to the silicon atom represented by R ¹ , for example, methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pen Aryl groups, such as phenyl group, tolyl group, xylyl group, naphthyl group, benzyl group, phenylethyl group, phenylpropyl group, such as an alkyl group, such as a methyl group, a neopentyl group, a hexyl group, a cyclohexyl group, an octyl group, a nonyl group, and a decyl group Alkenyl groups such as aralkyl groups, vinyl groups, allyl groups, propenyl groups, isopropenyl groups, butenyl groups, hexenyl groups, cyclohexenyl groups, octenyl groups, and the like, or some or all of the hydrogen atoms of these groups are fluorine, Substituted by halogen atoms, such as bromine and chlorine, and a cyano group, for example, a chloromethyl group, a chloropropyl group, a bromoethyl group, a trifluoropropyl group, a cyanoethyl group, etc. are mentioned, but all of R <^1> 90 It is preferable that mol% or more is a methyl group.

In this case, two or more of R <^1> need to be an alkenyl group (The thing of C2-C8 is more preferable, More preferably, it is C2-C6, Especially preferably, it is a vinyl group). Preferably 0.001-10 mol%, especially 0.01-5 mol% of all R <^1> are an alkenyl group. This alkenyl group may be bonded to the silicon atom at the terminal of the molecular chain, may be bonded to the silicon atom in the middle of the molecular chain, or may be bonded to both.

The structure of the organopolysiloxane preferably has a linear structure in which the main chain contains a repetition of diorganosiloxane units, and both ends of the molecular chain are sealed with a triorganosiloxy group, but is partially branched. May be a structure, an annular structure, or the like. Although it does not specifically limit about molecular weight, Although it can use from the liquid phase with low viscosity to the raw rubber phase with high viscosity, Usually, the average degree of polymerization (for example, weight average degree of polymerization) or the number of silicon atoms in 1 molecule is 100-50,000, Preferably it is 200- 20,000, more preferably, about 250 to 10,000.

Resinous copolymer of component (B) of the present invention is composed mainly of R ₃ SiO _1/2 units and SiO ₂ units. Here, R is an unsubstituted or substituted monovalent hydrocarbon group, preferably having 1 to 10 carbon atoms, particularly 1 to 8 carbon atoms. Examples of the monovalent hydrocarbon group represented by R include methyl, ethyl, propyl and iso Alkyl groups such as propyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, neopentyl group, hexyl group, cyclohexyl group, octyl group, nonyl group and decyl group, phenyl group, tolyl group, xylyl group, Aralkyl groups such as aryl groups such as naphthyl groups, benzyl groups, phenylethyl groups and phenylpropyl groups, such as vinyl groups, allyl groups, propenyl groups, isopropenyl groups, butenyl groups, hexenyl groups, cyclohexenyl groups and octenyl groups Alkenyl groups and those in which part or all of the hydrogen atoms of these groups are substituted with halogen atoms such as fluorine, bromine, chlorine, cyano groups, etc., for example, chloromethyl group, chloropropyl group, bromoethyl group, trifluoropropyl A group, a cyanoethyl group, etc. are mentioned.

(B) resinous copolymers of the component is the R ₃ SiO _1/2 units, and may include only the SiO ₂ units, as needed, R ₂ SiO units and RSiO _3/2 units (R is as described above) as the total amount thereof, may comprise less than 50% to the total copolymer weight, preferably in the range of 40% or less but, R ₃ SiO _1/2 molar ratio of the units and SiO ₂ units [R ₃ SiO _1/2 / SiO ₂ ] is 0.5 to 1.5, preferably 0.5 to 1.3. Even if this molar ratio is smaller than 0.5 or larger than 1.5, adhesiveness falls.

In addition, the resinous copolymer of component (B) has an alkenyl group content of 0.0001 mol / g or less (that is, 0 mol / g or more and 0.0001 mol / g or less), preferably 0.00005 mol / g or less (that is, 0 to 0.00005 mol / g), more preferably no alkenyl group. If the alkenyl group contains more than 0.0001 mol / g, sufficient adhesive force will not be obtained.

The resinous copolymer may be a liquid phase with fluidity at room temperature (for example 25 ° C.) or a solid phase without fluidity, but is preferably a solid phase at room temperature in terms of adhesiveness of the cured product. This resinous copolymer can be normally produced by hydrolyzing a suitable chlorosilane or alkoxysilane by a method well known in the art.

The compounding quantity of the resinous copolymer of these (B) component is the quantity used as 5-70 mass% with respect to the total amount of (A) component and (B) component, Preferably it is an amount used as 10-60 mass%. If it is less than 5 mass%, sufficient adhesiveness will not be obtained. If it exceeds 70 mass%, adhesiveness will also fall, and rubber property will also fall remarkably.

Component (C) of the present invention is an organohydrogenpolysiloxane having two or more, preferably three or more, hydrogen atoms (Si—H groups) bonded to silicon atoms in one molecule, wherein the Si—H groups in the molecule Since it crosslinks by the hydrosilyl addition reaction of the alkenyl group couple | bonded with the silicon atom in (A) component and (B) component, and hardens a composition, it acts as a hardening | curing agent. The organohydrogenpolysiloxane of this component (C) is 2 or more (usually about 2 to 200 pieces) in 1 molecule, Preferably it is 3 or more (usually about 3 to 100 pieces), More preferably, it is 3 to 50 Having two silicon atom-bonded hydrogen atoms, and those represented by the following average formula (2) are preferably used. In addition, this silicon atom-bonded hydrogen atom (Si-H group) may exist at the molecular chain terminal (i.e., monofunctional siloxy unit phase) or may exist in the middle of the molecular chain (bifunctional or trifunctional siloxane unit phase). May be present in both of them.

R ² _b H _c SiO _{(4-bc) / 2}

In the formula, R ² is a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, b is 0.7 to 2.1, c is 0.001 to 1.0, and b + c is a positive number satisfying 0.8 to 3.0.

Here, the monovalent hydrocarbon group for R ^2, but include those of the same as those exemplified in R ^1, preferably not having aliphatic unsaturated. In addition, b is 0.8 to 2.0, c is 0.01 to 1.0, and b + c is preferably 1.0 to 2.5, and the molecular structure of the organohydrogenpolysiloxane may be any one of a linear, cyclic, branched and three-dimensional mesh. It may be.

In this case, the number (or degree of polymerization) of silicon atoms in one molecule is preferably used in a liquid state at room temperature (25 ° C.) of about 2 to 300, particularly about 4 to 150. In addition, the hydrogen atom couple | bonded with a silicon atom may be located in any of the molecular chain terminal, the middle of a molecular chain, and may be located in both.

As organohydrogenpolysiloxane of the said (C) component, 1,1,3,3- tetramethyldisiloxane, 1,3,5,7-tetramethylcyclotetrasiloxane, a methylhydrogen cyclic cyclic polymer, methyl hydroxide Rosensiloxane, dimethylsiloxane cyclic copolymer, tris (dimethyl hydrogen siloxy) methyl silane, tris (dimethyl hydrogen siloxy) phenyl silane, both terminal trimethylsiloxy group blocking methylhydrogenpolysiloxane, both terminal trimethylsiloxy group blocking dimethylsiloxane Methyl hydrogensiloxane copolymer, both terminal dimethyl hydrogen siloxy group blocking dimethylpolysiloxane, both terminal dimethyl hydrogen siloxy group blocking dimethylsiloxane, methyl hydrogen siloxane copolymer, both terminal trimethylsiloxy group blocking methyl hydrogen siloxane diphenyl Siloxane copolymer, both terminal trimethylsiloxy group blockade methylhydrogensiloxane diphenylsiloxane dimethylsiloxane air _{Copolymer, (CH 3) 2 HSiO 1} /2 units and SiO _4/2 units of the copolymer, containing (CH _{3) 2} HSiO _1/2 units and SiO _4/2 units and _{(C 6 H 5) SiO 3} / _The copolymer containing _two units, etc. are mentioned.

It is preferable that the compounding quantity of this organohydrogenpolysiloxane is 0.2-30 mass parts with respect to a total of 100 mass parts of (A) and (B) component, and is 0.5-15 mass parts. Sufficient rubber strength is not obtained even when the blending amount is less than 0.2 part by mass or exceeds 30 parts by mass.

The fine powder silica of component (D) of the present invention is added to improve rubber strength, and may be any of those containing SiO ₂ as a main component, but preferably from fumed silica, precipitated silica, diatomaceous earth, ground quartz and fused quartz. It is preferable to use 1 type of what is chosen individually or in combination of 2 or more types.

It is preferable that the average particle diameter of fine powder silica is 20 micrometers or less, More preferably, it is 10 micrometers or less, More preferably, it is 7 micrometers or less, When it exceeds 20 micrometers, rubber strength cannot be improved and it may fall conversely. have. In addition, it is preferable that average particle diameters are 0.5 micrometer or more, especially 1 micrometer or more about silicas other than fumed silica and precipitated silica. For fumed silica and precipitated silica, the primary particle diameter is sufficiently smaller than 5 mu m (typically around 0.001 to 1 mu m), and rather, the definition in specific surface area is preferred. In this case, the specific surface area by BET method is 50-400 m <2> / g, More preferably, it is 80-350 m <2> / g. In addition, the average particle diameter in the present invention, for example, a cumulative weight average value of the particle size distribution measured by laser light diffraction can be measured such as a D ₅₀ (or median diameter).

These fine powder silicas may be used as they are, but may be those previously treated with a surface hydrophobization treatment agent, or kneaded with one or two or more silicone oils of (A), (B) and (C) components (i.e., In the compounding process of a composition, what added and processed the surface treating agent can also be used. These surface treating agents may be any known ones such as alkylalkoxysilane, alkylchlorosilane, alkylsilazane, silane coupling agent, titanate treatment agent, fatty acid ester, etc., and may be used alone or in combination of two or more. Can also be used at time points.

Moreover, it is preferable that the compounding quantity of these fine powder silicas is 1-200 mass parts with respect to a total of 100 mass parts of (A) and (B) component, and it is 3-100 mass parts. If the blending amount is less than 1 part by mass, sufficient rubber strength cannot be obtained. If the blending amount is more than 200 parts by mass, the blending becomes difficult.

The heat resistance imparting agent of component (E) may be any of various organic antioxidants such as hydrates, carbonates, organic acid salts, BHT, and the like, which are used for the purpose of improving heat resistance in silicone rubber. Among these, a metal oxide is preferable at the point which does not adversely affect adhesiveness or curability especially. Examples of such metal oxides include iron oxide, titanium oxide, cerium oxide, magnesium oxide, aluminum oxide, zinc oxide, and the like, and iron oxide and cerium oxide are particularly preferable. These can be used individually by 1 type or in mixture of 2 or more types.

The compounding quantity of these heat resistance imparting agents is 0.05-50 mass parts with respect to a total of 100 mass parts of (A) and (B) component, Preferably it is 0.2-20 mass parts. If the blending amount is less than 0.05 parts by mass, the heat resistance is hardly improved. If the blending amount is more than 50 parts by mass, the rubber properties decrease.

Examples of the addition reaction catalyst for component (F) include platinum black, chloroplatinum, chloroplatinic acid, reactants of chloroplatinic acid and monohydric alcohols, complexes of chloroplatinic acid and olefins, platinum-based catalysts such as platinum bisacetoacetate, and palladium-based catalysts. And rhodium-based catalysts. In addition, the compounding quantity of this addition reaction catalyst can be made into the amount of catalysts, and is normally 0.5-1,000 ppm with respect to the total mass of (A), (B), (C) component as a platinum group metal, especially about 1-500 ppm.

As another component, you may mix | blend fillers, such as conductive agents, such as carbon black, electroconductive zincation, a metal powder, and a coloring pigment, as needed in the range which does not impair the objective of this invention. Optionally, a hydrosilylation reaction control agent such as a nitrogen-containing compound, an acetylene compound, a phosphorus compound, a nitrile compound, a carboxylate, a tin compound, a mercury compound, a sulfur compound, an internal mold release agent such as dimethyl silicone oil, an adhesion imparting agent, Thixotropy etc. can also be mix | blended suitably.

Moreover, in addition to these, you may add a solvent in order to reduce a viscosity. As a solvent, dissolution of silicone is possible, and any may be sufficient as a boiling point 200 degrees C or less. For example, xylene, toluene, benzene, heptane, hexane, cyclohexane, trichloroethylene, perchloroethylene, methylene chloride, ethyl acetate, methyl isobutyl ketone, methyl ethyl ketone, butanol, ligroin, cyclohexanone, diethyl And organic solvents such as ether, petroleum ether, industrial gasoline, rubber gasoline, and silicone solvents, and these may be used alone or in combination of two or more thereof as a mixed solvent.

The adhesive rubber sheet of this invention is obtained by hardening the addition hardening type silicone rubber composition containing the said component. In this case, as a method of obtaining an adhesive rubber sheet using the silicone rubber composition of the present invention, more specifically, the silicone rubber composition may be directly obtained by compression molding, injection molding, injection molding, or the like. And a method of forming a sheet on a metal substrate, a resin substrate, a resin film, or a method of obtaining a rubber sheet integrated with a substrate by dipping, coating, screen printing, or the like.

As hardening conditions of an addition hardening type silicone rubber composition, the range of 10 second-1 hour is preferable at the temperature of 80-250 degreeC. In addition, post-curing may be performed for about 1 to 100 hours at a temperature of 120 to 250 ° C for the purpose of excluding the low molecular siloxane. In addition, the thickness of the rubber sheet is preferably 0.05 to 50 mm, more preferably 0.1 to 20 mm. If it is less than 0.05 mm, it may be insufficient to improve the elasticity of the sheet, and if it exceeds 50 mm, it is disadvantageously costly.

The rubber sheet thus obtained has adhesiveness on the surface, and the surface adhesive force measured by the texture analyzer (manufactured by Texture Technologies Corp.) is preferably 20 to 300 g, particularly 30 to 200 g, and in the present invention, 250 After being left in the oven at 12C for 12 hours, it is preferable that the adhesive force of the cooled rubber sheet is maintained at 70% or more, particularly 80% or more, of the initial adhesive force.

In addition, the hardness of the rubber sheet of the present invention is preferably in the range of 5 to 50, more preferably in the range of 5 to 40 with a durometer A durometer. If it is less than 5, the strength as rubber may be insufficient, and if it exceeds 50, the adhesiveness may be lowered. The rubber strength is preferably 0.5 MPa or more, more preferably 0.8 MPa or more, as measured by JIS K6249. If it is less than 0.5 MPa, it is easily broken when used in the production line of an electronic component, and there exists a possibility that it cannot endure repeated use.

The adhesive rubber sheet of this invention can be used as an adhesive fixing sheet, when manufacturing various electronic components, such as chip type electronic components, such as a capacitor | condenser, an actuator, an inductor, and mounting of a flexible printed circuit board.

<Examples>

Hereinafter, although an Example and a comparative example are given and this invention is demonstrated further more concretely, this invention is not limited to the following Example. In addition, represents in each example section parts by mass, average particle diameter indicates a value measured as a cumulative weight average value (D ₅₀₎ in the particle size distribution measured by laser light diffraction method, the specific surface area represents the value measured by the BET method .

Example 1

Both ends of a dimethylvinylsiloxy the dimethylpolysiloxane (1) 60 parts of the average degree of polymerization blocked with time 300, at room temperature the solid _{(CH 3) 3 SiO 1/} 2 number that includes units and SiO ₂ units lipid copolymer (2 ) ((CH ₃ ) ₃ SiO _1/2 unit / SiO ₂ unit (molar ratio) = 0.75] 40 parts, finely powdered silica, hydrophobized fumed silica having a specific surface area of 110 m 2 / g (Nippon Aerosil Co., Ltd.) Preparation, R-972) 8 parts, having an average particle size of 0.10 ㎛ iron oxide (Fe ₂ O ₃₎ 1 parts into a planetary mixer, and mixed for 30 minutes, and passed through rolls once to three. To 100 parts of the silicone rubber base, methylhydrogenpolysiloxane (3) having a Si—H group in the molecular side chain (that is, on the siloxane unit in the middle of the molecular chain) as a crosslinking agent (polymerization degree 20, amount of Si—H group 0.0060 mol / 0.99 parts of g) and 0.05 part of ethynyl cyclohexanol were added as a reaction control agent, and stirring was continued for 15 minutes, and the silicone rubber composition was obtained. 0.1 part of platinum catalyst (Pt concentration 1%) was mixed with this silicone rubber composition, and the rubber sheet of thickness 2mm which has adhesiveness on the surface was obtained by press hardening at 120 degreeC for 10 minutes. About this hardened | cured material, the result of having measured rubber hardness (durometer A), tensile strength, and elongation at the time of cutting based on JISK6249 from 2 mm sheet is shown in following Table 1. Furthermore, the surface adhesive force was measured by the texture analyzer from the 2 mm sheet, the rubber sheet was left in an oven at 250 ° C. for 12 hours, cooled, and the adhesive force was again measured. The results are shown in Table 1.

[Example 2]

70 parts of dimethylpolysiloxane (1) of Example 1, 15 parts of fumed silica (Nebon Aerosol Co., Ltd., Aerosil 200) having a specific surface area of 200 m 2 / g, 3 parts of hexamethyldisilazane, One part of water was kneaded at 150 ° C. for 2 hours. 30 parts of the resinous copolymer (2) of Example 1 was added thereto, and kneading was further continued at 150 ° C for 2 hours. 0.5 parts of cerium oxide having an average particle diameter of 1 µm and 2 parts of titanium oxide having an average particle diameter of 100 µm of the silicone rubber base, and a methylhydrogenpolysiloxane having a Si—H group in the molecular side chain of Example 1 as a crosslinking agent ( 1.26 parts of 3) and 0.05 part of ethynyl cyclohexanol were added as a reaction control agent, and stirring was continued for 15 minutes, and the silicone rubber composition was obtained. 0.1 part of platinum catalyst (Pt concentration 1%) was mixed with this silicone rubber composition, and the rubber sheet of thickness 2mm which has adhesiveness on the surface was obtained by press hardening at 120 degreeC for 10 minutes. About this hardened | cured material, rubber hardness (durometer A), tensile strength, elongation at the time of cutting | disconnection, and the surface adhesive force before and behind a heat test were measured similarly to Example 1. The results are shown in Table 1.

[Example 3]

60 parts of dimethylpolysiloxane (4) (vinyl group content 0.0002 mol / g) with the average degree of polymerization having 500 vinyl groups bonded to Si atoms in the molecular side chain, both ends of which are sealed with trimethylsiloxy groups, and solid at room temperature dissolved in toluene. _{(CH 3) 3 SiO 1/} 2 units, SiO ₂ units and (CH _{3) 2} can containing SiO units lipid copolymer _{(5) [(CH 3)} 3 SiO 1/2 unit / SiO ₂ unit (molar ratio) = 0.80, content of 15 mol% of (CH ₃ ) ₂ SiO] 40 parts (resin) were mixed at room temperature, and the solvent was removed at 120 ° C. under reduced pressure for 3 hours, followed by further stirring for 1 hour. The silicone rubber base, 100 parts of diatomaceous earth (10 parts) having an average particle diameter of 7 ㎛ to, the 30 parts of a quartz powder having an average particle diameter of 2 ㎛, average particle size 0.3 ㎛ of iron oxide (Fe ₂ O ₃₎ 1 part, the molecules of Example 1 as a crosslinking agent 2.25 parts of methylhydrogenpolysiloxane (3) which has Si-H group in a side chain, 0.05 part of ethynyl cyclohexanol as a reaction control agent was added, and stirring was continued for 15 minutes, and the silicone rubber composition was obtained. 0.1 part of platinum catalyst (Pt concentration 1%) was mixed with this silicone rubber composition, and the rubber sheet of thickness 2mm which has adhesiveness on the surface was obtained by press hardening at 120 degreeC for 10 minutes. About this hardened | cured material, rubber hardness (durometer A), tensile strength, elongation at the time of cutting | disconnection, and the surface adhesive force before and behind a heat test were measured similarly to Example 1. The results are shown in Table 1.

Comparative Example 1

60 parts of dimethylpolysiloxane (1) of Example 1, 40 parts of resinous copolymer (2) of Example 1, hydrophobized fumed silica having a specific surface area of 110 m 2 / g as fine powder silica (Nippon Aerosil Co., Ltd.) 8 parts of R-972) was put into a planetary mixer, mixed for 30 minutes, and then passed through three rolls once. 0.99 parts of methylhydrogenpolysiloxane (3) which has Si-H group in the molecular side chain of Example 1 as a crosslinking agent is added to 100 parts of this silicone rubber bases, and 0.05 parts of ethynyl cyclohexanol as reaction control agent, and it stirs for 15 minutes. Then, the silicone rubber composition was obtained. 0.1 part of platinum catalyst (Pt concentration 1%) was mixed with this silicone rubber composition, and the rubber sheet of thickness 2mm which has adhesiveness on the surface was obtained by press hardening at 120 degreeC for 10 minutes. About this hardened | cured material, rubber hardness (durometer A), tensile strength, elongation at the time of cutting | disconnection, and the surface adhesive force before and behind a heat test were measured similarly to Example 1. The results are shown in Table 1.

Comparative Example 2

55 parts of dimethylpolysiloxane (1) of Example 1, 15 parts of fumed silica (Nebon Aerosol Co., Ltd., Aerosil 200) having a specific surface area of 200 m 2 / g, 3 parts of hexamethyldisilazane, One part of water was kneaded at 150 ° C. for 2 hours. 30 parts of the resinous copolymer (2) of Example 1 was added thereto, and kneading was further continued at 150 ° C for 2 hours. 1.26 parts of methylhydrogenpolysiloxane (3) which has Si-H group in the molecular side chain of Example 1 as a crosslinking agent is added to 100 parts of this silicone rubber bases, and 0.05 parts of ethynyl cyclohexanol as reaction control agent, and it stirs for 15 minutes. Then, the silicone rubber composition was obtained. 0.1 part of platinum catalyst (Pt concentration 1%) was mixed with this silicone rubber composition, and the rubber sheet of thickness 2mm which has adhesiveness on the surface was obtained by press hardening at 120 degreeC for 10 minutes. About this hardened | cured material, rubber hardness (durometer A), tensile strength, elongation at the time of cutting | disconnection, and the surface adhesive force before and behind a heat test were measured similarly to Example 1. The results are shown in Table 1.

[Comparative Example 3]

60 parts of dimethylpolysiloxane (4) of Example 3 and 40 parts of the resinous copolymer (5) of Example 3 dissolved in toluene were mixed at room temperature, and the solvent was removed at 120 ° C. for 3 hours under reduced pressure, followed by further 1 Stirring was continued for hours. In this silicone rubber base, 100 parts, having an average particle size of 0.3 ㎛ iron oxide (Fe ₂ O ₃₎ 1 part, the methylhydroxy hydrogen polysiloxane (3) having Si-H in the molecular side chain of Example 1 as a crosslinking agent, 2.25 parts of reactants 0.05 part of ethynyl cyclohexanol was added as a yesterday, and stirring was continued for 15 minutes, and the silicone rubber composition was obtained.

0.1 part of platinum catalyst (Pt concentration 1%) was mixed with this silicone rubber composition, and the rubber sheet of thickness 2mm which has adhesiveness on the surface was obtained by press hardening at 120 degreeC for 10 minutes. About this hardened | cured material, rubber hardness (durometer A), tensile strength, elongation at the time of cutting | disconnection, and the surface adhesive force before and behind a heat test were measured similarly to Example 1. The results are shown in Table 1.

The addition-curable silicone rubber composition of the present invention is excellent in moldability, and the cured product can be a silicone rubber sheet having high rubber strength and surface adhesiveness and excellent heat resistance with a small drop in adhesive strength even when exposed to high temperature.

Claims (9)

(A) 30 to 95 parts by mass of an organopolysiloxane containing two or more alkenyl groups having 2 to 8 carbon atoms bonded to a silicon atom in one molecule, (B) R ₃ SiO _1/2 units (wherein R is a monovalent hydrocarbon group selected from unsubstituted or halogen substituted alkyl, alkenyl, aryl and aralkyl groups having 1 to 10 carbon atoms) and SiO ₂ units And molar ratio [R ₃ SiO _1/2 / SiO ₂ ] between R ₃ SiO _1/2 units and SiO ₂ units is 0.5 to 1.5, and the total amount is 0.0001 mol even if R does not contain or contains an alkenyl group. 5 to 70 parts by mass of the resinous copolymer having a / g or less, provided that the sum of the components (A) and (B) is 100 parts by mass), (C) 0.2-30 mass parts of organohydrogenpolysiloxane containing 2 or more of hydrogen atoms couple | bonded with a silicon atom in 1 molecule, (D) 1 to 200 parts by mass of fine powder silica, (E) 0.05-50 parts by mass of heat resistance imparting agent, (F) catalytic amount addition reaction catalyst It is contained, and the hardened | cured material of this has surface adhesiveness, The addition hardening type silicone rubber composition characterized by the above-mentioned. The addition-curable silicone rubber composition according to claim 1, wherein the resinous copolymer of component (B) has an alkenyl group content of 0 mol / g or more and 0.0001 mol / g or less and is solid at room temperature. The addition-curable silicone rubber composition according to claim 1 or 2, wherein the heat resistance imparting agent of component (E) is a metal oxide. 4. The addition curable silicone rubber composition according to claim 3, wherein the metal oxide is selected from iron oxide, cerium oxide, titanium oxide, aluminum oxide, magnesium oxide and zinc oxide. The addition-curable silicone rubber composition according to claim 1 or 2, wherein the hardness of the silicone rubber after curing is 5 to 50 and a tensile strength of 0.5 MPa or more in the durometer A. The addition-curable silicone rubber composition according to claim 1 or 2, wherein the adhesive force after leaving the silicone rubber after curing for 12 hours at 250 ° C. is 70% or more of the initial adhesive force. The adhesive rubber sheet which hardens the addition-curable silicone rubber composition of Claim 1 or 2. The adhesive rubber sheet according to claim 7, which is for adhesive fixing of electronic components. The pressure-sensitive adhesive rubber sheet according to claim 8, wherein the electronic component is a chip-shaped electronic component or a flexible printed board selected from a capacitor, an actuator, and an inductor.