Silicone adhesive composition, adhesive tape and adhesive film

Abstract

An object of the present invention is to provide a silicone adhesive composition that provides an adhesive layer having a strong adhesive force to silicone rubber and capable of maintaining a high storage elastic modulus G' even at room temperature or a high temperature, and an adhesive tape and an adhesive film each including an adhesive layer formed of a cured product of the adhesive composition.SOLUTION: (I) at least one linear organopolysiloxane and at least one of organopolysiloxane resins having a R33SiO1 / 2 unit and a SiO4 / 2 unit, or (II) a condensation reaction product of at least one linear organopolysiloxane and at least one of organopolysiloxane resins having a R33SiO1 / 2 unit and a SiO4 / 2 unit.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a silicone pressure-sensitive adhesive composition, and more specifically to a silicone pressure-sensitive adhesive composition that provides an adhesive layer that has strong adhesion to silicone rubber and a high storage modulus G' at room temperature and at high temperatures, and to a pressure-sensitive adhesive tape and pressure-sensitive adhesive film that include an adhesive layer made of a cured product of the pressure-sensitive adhesive composition. [Background technology]

[0002] The polysiloxane that makes up the silicone pressure-sensitive adhesive has excellent heat resistance, cold resistance, weather resistance, electrical insulation, and chemical resistance, and is therefore used in harsh environments such as heat-resistant pressure-sensitive adhesive tapes, electrical insulating pressure-sensitive adhesive tapes, masking tapes for manufacturing processes, temporary fixing tapes, heat-sealing tapes, and flame-retardant mica tapes.

[0003] Silicone pressure-sensitive adhesives also exhibit excellent wettability with a variety of adherends, and are adhesive to silicone resins, polyolefins, fluororesins, silicone rubber, silicone release paper, etc., which are difficult to adhere to with organic resin pressure-sensitive adhesives such as acrylic pressure-sensitive adhesives, rubber pressure-sensitive adhesives, and urethane pressure-sensitive adhesives. For this reason, silicone pressure-sensitive adhesives are considered suitable for adhesive tapes used, for example, when bonding or fixing a silicone rubber member to another member.

[0004] Furthermore, in recent years, there has been an increase in the use of adhesive tape to secure silicone rubber parts used in electronic devices, such as conductive silicone rubber, heat-dissipating silicone rubber, vibration-proof silicone rubber, selective adhesive LIMS, and electromagnetic wave blocking silicone rubber, and this has led to an increase in demand for adhesives that can adhere stably to silicone rubber.

[0005] Conventional adhesive tapes using silicone adhesives for silicone rubber typically use peroxide-curable silicone adhesive compositions. However, peroxide-curable silicone adhesive compositions have a high curing temperature, making them unsuitable for use on substrates with low heat distortion temperatures and in terms of energy costs. Another problem is the residue of benzoic acid, a decomposition product of peroxide. Meanwhile, silicone adhesives for silicone rubber using addition-reaction-curable silicone adhesive compositions provide stable adhesion to various metals and tape substrates, but exhibit low adhesion to silicone rubber. Furthermore, exposure to high temperatures can cause the edges of the adhesive tape to peel and lift, or the adhesive tape to peel and cause parts to fall off. This is due to a decrease in the storage modulus G' of the silicone adhesive layer when heated, resulting in a corresponding decrease in the adhesive strength of the adhesive layer.

[0006] As improvements to silicone rubber adhesives based on addition reaction curing silicone adhesive compositions, the following are known: a silicone adhesive composition containing an organosilicon compound having a BO-Si bond (Patent Document 1), a silicone adhesive composition using a mixture of an alkenyl-containing diorganopolysiloxane and an alkenyl-free diorganopolysiloxane (Patent Document 2), a silicone adhesive composition containing a metal compound (Patent Document 3), and a silicone adhesive composition containing a specific organopolysiloxane containing T units and D units (Patent Document 4).However, all of these compositions have insufficient adhesive strength to silicone rubber, and there is no mention of the storage modulus G' at high temperatures. Instead of the storage modulus G' at high temperatures, the holding strength at high temperatures was measured, but the results were low.

[0007] In addition, in a silicone pressure-sensitive adhesive composition (Patent Document 5) in which the molar ratio of SiH groups in the organohydrogenpolysiloxane to the alkenyl groups in the linear diorganopolysiloxane is 50 to 2,000, the adhesive strength to silicone rubber is improved, but the storage modulus G' at high temperatures is insufficient.Furthermore, because of the large number of SiH groups, there is a problem in that when the adhesive layer is made thick, air bubbles remain in the pressure-sensitive adhesive layer due to a dehydrogenation reaction. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Publication No. 7-11228 [Patent Document 2] Japanese Patent Application Laid-Open No. 2008-24777 [Patent Document 3] Japanese Patent Application Laid-Open No. 2010-13632 [Patent Document 4] Japanese Patent Application Laid-Open No. 2011-1448 [Patent Document 5] Japanese Patent Application Publication No. 2017-222819 Summary of the Invention [Problem to be solved by the invention]

[0009] As mentioned above, there are no silicone pressure-sensitive adhesives that have strong adhesive strength to silicone rubber and can maintain a high storage modulus G' at room temperature or in a high-temperature environment.

[0010] The present invention has been made in view of the above circumstances, and aims to provide a silicone pressure-sensitive adhesive composition that provides an adhesive layer that has strong adhesion to silicone rubber and can maintain a high storage modulus G' even at room temperature or at high temperatures, and an adhesive tape and adhesive film that have an adhesive layer made of a cured product of the pressure-sensitive adhesive composition. [Means for solving the problem]

[0011] As a result of extensive research conducted by the present inventors to achieve the above object, it was discovered that an addition reaction curable silicone pressure sensitive adhesive composition contains (A) a linear organopolysiloxane containing a specific amount of alkenyl groups, (B) R 3 3SiO 1 / 2 Units and SiO 4 / 2 The present inventors have found that the above object can be achieved by blending specific amounts of an organopolysiloxane resin having units in a specific ratio and a specific weight-average molecular weight, and (C) an organohydrogenpolysiloxane, respectively, and have completed the present invention.

[0012] That is, the present invention provides a method for producing a polysiloxane comprising the steps of [1] (I) at least one linear organopolysiloxane and R 3 3SiO 1 / 2 Units and SiO 4 / 2 or (II) at least one linear organopolysiloxane and an organopolysiloxane resin having a unit R 3 3SiO 1 / 2 Units and SiO 4 / 2 A silicone pressure-sensitive adhesive composition comprising a condensation reaction product of at least one organopolysiloxane resin having a hydroxyl group unit, The linear organopolysiloxane in (I) and (II) is (A) a linear organopolysiloxane having one or more alkenyl groups per molecule, with an alkenyl group content of 0.0001 to 0.03 mol / 100 g, and optionally having a silicon-bonded hydroxyl group or a C1 to C6 alkoxy group, and optionally (A') a linear organopolysiloxane having no alkenyl groups and no silicon-bonded hydrogen atoms, The organopolysiloxane resin in (I) and (II) is (B)R 3 3SiO 1 / 2 Units and SiO 4 / 2 units, and has a hydroxyl group and / or an alkoxy group having 1 to 6 carbon atoms bonded to a silicon atom, (R 3 3SiO 1 / 2 Unit) / (SiO 4 / 2 The organopolysiloxane resin (wherein R 3are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, a hydroxyl group, or an alkoxy group having 1 to 6 carbon atoms), the organopolysiloxane resin containing no alkenyl groups or containing alkenyl groups in an amount such that the total amount of alkenyl groups in the organopolysiloxane resin is less than 0.005 mol / 100 g, and having a weight average molecular weight of 5,000 or more as measured by gel permeation chromatography relative to standard polystyrene; The silicone pressure-sensitive adhesive composition further comprises: (C) Organohydrogenpolysiloxane having three or more hydrogen atoms bonded to silicon atoms in one molecule an amount such that the ratio of the total number of SiH groups in component (C) to the total number of alkenyl groups in the alkenyl group-containing organopolysiloxane contained in the silicone pressure-sensitive adhesive composition is 0.1 to 30.0; and (D) a catalytic amount of a platinum group metal catalyst; The silicone pressure-sensitive adhesive composition is provided, wherein the ratio of the total mass of the linear organopolysiloxane to the total mass of the organopolysiloxane resin is 25 / 75 to 70 / 30.

[0013] The present invention further provides the silicone pressure-sensitive adhesive composition, which further comprises at least one of the following features [2] to

[13] : [2] The silicone pressure-sensitive adhesive composition, wherein the amount of the component (A) is 0.1 to 70 mass%, the amount of the component (B) is 0.01 to 70 mass%, and the amount of the component (A') is 0 to 50 mass%, relative to the total mass of the silicone pressure-sensitive adhesive composition. [3](F)R 3 3SiO 1 / 2 Units and SiO 4 / 2 It has units (R 3 3SiO 1 / 2 Unit) / (SiO 4 / 2The organopolysiloxane resin (wherein R 3 and each independently represent a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, a hydroxyl group, or an alkoxy group having 1 to 6 carbon atoms) in an amount of 0.01 to 45 mass% relative to the total mass of the silicone pressure-sensitive adhesive composition. [4] The silicone pressure-sensitive adhesive composition, comprising a condensation reaction product of the component (A), optionally the component (A'), the component (B), and the component (F). [5] The silicone pressure-sensitive adhesive composition, which comprises the component (A), optionally the component (A'), and a condensation reaction product of the component (B), and further comprises the component (F). [6](E)R 3 3SiO 1 / 2 Units and SiO 4 / 2 units, and has a hydroxyl group and / or an alkoxy group having 1 to 6 carbon atoms bonded to a silicon atom, (R 3 3SiO 1 / 2 Unit) / (SiO 4 / 2 The organopolysiloxane resin (wherein R 3 and each independently represent a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, a hydroxyl group, or an alkoxy group having 1 to 6 carbon atoms), and the organopolysiloxane resin does not contain alkenyl groups or contains alkenyl groups in such an amount that the total amount of alkenyl groups in the organopolysiloxane resin is less than 0.005 mol / 100 g, and the organopolysiloxane resin has a weight average molecular weight (Mw) of less than 5,000 as measured by gel permeation chromatography (GPC) relative to standard polystyrene standards, in an amount of 0.01 to 35 mass %, relative to the total mass of the silicone pressure-sensitive adhesive composition. [7] The silicone pressure-sensitive adhesive composition, comprising a condensation reaction product of the component (A), optionally the component (A'), the component (B), the component (E), and the component (F). [8](E)R 3 3SiO 1 / 2 Units and SiO 4 / 2 units, and has a hydroxyl group and / or an alkoxy group having 1 to 6 carbon atoms bonded to a silicon atom, (R 3 3SiO 1 / 2 Unit) / (SiO 4 / 2 The organopolysiloxane resin (wherein R 3 and each independently represent a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, a hydroxyl group, or an alkoxy group having 1 to 6 carbon atoms), and the organopolysiloxane resin does not contain alkenyl groups or contains alkenyl groups in such an amount that the total amount of alkenyl groups in the organopolysiloxane resin is less than 0.005 mol / 100 g, and the organopolysiloxane resin has a weight average molecular weight (Mw) of less than 5,000 as measured by gel permeation chromatography (GPC) relative to standard polystyrene, in an amount of 0.01 to 35 mass %, relative to the total mass of the silicone pressure-sensitive adhesive composition. [9] The silicone pressure-sensitive adhesive composition, comprising a condensation reaction product of the component (A), optionally the component (A'), the component (B), the component (E), and the component (F).

[10] The silicone pressure-sensitive adhesive composition, comprising a condensation reaction product of the component (A), optionally the component (A'), the component (B), and the component (E), and further comprising the component (F).

[11] The silicone pressure-sensitive adhesive composition, wherein the component (A) is represented by the following formula (1): [ka] (In the formula, R 1 are each independently a hydroxyl group, an alkoxy group having 1 to 6 carbon atoms, or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, provided that R 1 at least one of R is an alkenyl-containing organic group having 2 to 10 carbon atoms;1 the ratio of the number of hydroxyl groups to the total number of groups is 10% or less, the alkenyl group content in the organopolysiloxane is 0.0001 to 0.03 mol / 100 g, and a is a positive number such that a solution of the organopolysiloxane dissolved in toluene to a concentration of 30% by mass has a viscosity of 1,000 to 200,000 mPa s at 25°C.

[12] The component (F) further comprises R 5 R 6 SiO 2 / 2 units (wherein R 5 is the above R other than an alkenyl group. 3 and R 6 is an alkenyl group having 2 to 10 carbon atoms), (R 5 R 6 SiO 2 / 2 Unit) / (SiO 4 / 2 The silicone pressure-sensitive adhesive composition is an organopolysiloxane resin having a molar ratio represented by the unit (a) of 0.01 to 0.5.

[13] Any of the above silicone pressure-sensitive adhesive compositions, wherein the adhesive strength of a 40 μm-thick cured layer formed by curing the silicone pressure-sensitive adhesive composition to a silicone rubber sheet is 3.0 N / 25 mm or more, as measured using a 180° peel test method at a tensile speed of 300 mm / min.

[0014] The present invention further provides a cured product obtained by curing the above-mentioned silicone pressure-sensitive adhesive composition.The present invention further provides the above-mentioned cured product, in which the adhesive layer formed from the cured product obtained by curing the above-mentioned silicone pressure-sensitive adhesive composition has a storage modulus G' of 1.00 MPa or more at 25°C.The present invention further provides the above-mentioned cured product, in which the adhesive layer formed from the cured product obtained by curing the above-mentioned silicone pressure-sensitive adhesive composition has a storage modulus G' of 0.10 MPa or more at 80°C. The present invention further provides a pressure-sensitive adhesive tape comprising a substrate and an adhesive layer formed on at least one surface of the substrate, wherein the adhesive layer is a cured product formed by curing the above-mentioned silicone pressure-sensitive adhesive composition.The present invention also provides a pressure-sensitive adhesive film comprising a substrate and an adhesive layer formed on at least one surface of the substrate, wherein the adhesive layer is a cured product formed by curing the above-mentioned silicone pressure-sensitive adhesive composition. [Effects of the Invention]

[0015] An adhesive tape or film having an adhesive layer formed by curing the silicone adhesive composition of the present invention has strong adhesive strength to silicone rubber and can maintain a high storage modulus G' even at high temperatures. Therefore, this adhesive tape or film can be suitably used for adhering and bonding silicone materials, as masking tape or temporary fixing tape in the manufacturing process of electronic components or semiconductor components, or as a member for electronic materials or display devices. DETAILED DESCRIPTION OF THE INVENTION

[0016] The silicone pressure-sensitive adhesive composition of the present invention will now be described in more detail.

[0017] The present invention relates to a composition comprising (I) at least one linear organopolysiloxane and R 3 3SiO 1 / 2 units (so-called M units) and SiO 4 / 2 (II) at least one organopolysiloxane resin having a unit (so-called Q unit) (so-called MQ resin), or (II) at least one linear organopolysiloxane and R 3 3SiO 1 / 2 units (so-called M units) and SiO 4 / 2 The silicone pressure-sensitive adhesive composition contains a condensation reaction product of at least one organopolysiloxane resin (so-called MQ resin) having units (so-called Q units). The silicone pressure-sensitive adhesive composition containing the above (I) may further contain the condensation reaction product shown in the above (II).

[0018] The linear organopolysiloxane in (I) and (II) above includes (A) a linear organopolysiloxane having one or more alkenyl groups per molecule, an alkenyl group content of 0.0001 to 0.03 mol / 100 g, and optionally having a silicon-bonded hydroxyl group or a C alkoxy group. The linear organopolysiloxane may further include, optionally, (A') a linear organopolysiloxane having no alkenyl groups and no silicon-bonded hydrogen atoms.

[0019] The organopolysiloxane resin (MQ resin) in (I) and (II) above is (B)R 3 3SiO 1 / 2 Units and SiO 4 / 2 units and has hydroxyl groups and / or alkoxy groups having 1 to 6 carbon atoms bonded to silicon atoms, (R 3 3SiO 1 / 2 Unit) / (SiO 4 / 2 The organopolysiloxane resin (wherein R 3 are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, a hydroxyl group, or an alkoxy group having 1 to 6 carbon atoms), which does not contain alkenyl groups or contains alkenyl groups in an amount such that the total amount of alkenyl groups in the organopolysiloxane resin is less than 0.005 mol / 100 g, and which has a weight average molecular weight (Mw) of 5,000 or more as measured by gel permeation chromatography (GPC) relative to standard polystyrene.

[0020] The organopolysiloxane resin (MQ resin) may further contain (F) an MQ resin having one or more alkenyl groups per molecule, with the alkenyl group content being 0.005 to 0.5 mol / 100 g, in an amount of 0.01 to 45 mass % relative to the total mass of the silicone pressure-sensitive adhesive composition. 3 3SiO 1 / 2 Units and SiO 4 / 2is an organopolysiloxane resin having units (R 3 3SiO 1 / 2 Unit) / (SiO 4 / 2 The molar ratio of R to C is 0.5 to 1.5, and optionally has a hydroxyl group bonded to a silicon atom and / or an alkoxy group having 1 to 6 carbon atoms bonded to a silicon atom. 3 are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, a hydroxyl group, or an alkoxy group having 1 to 6 carbon atoms.

[0021] The organopolysiloxane resin (MQ resin) may further contain (E) an MQ resin having a weight average molecular weight (Mw) of less than 5,000 as measured by gel permeation chromatography (GPC) relative to standard polystyrene standards, and a total amount of alkenyl groups of less than 0.005 mol / 100 g, in an amount of 0.01 to 35% by mass relative to the total mass of the silicone pressure-sensitive adhesive composition. 3 3SiO 1 / 2 Units and SiO 4 / 2 units and has hydroxyl groups and / or alkoxy groups having 1 to 6 carbon atoms bonded to silicon atoms, (R 3 3SiO 1 / 2 Unit) / (SiO 4 / 2 The molar ratio represented by R is 0.5 to 1.5. 3 are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, a hydroxyl group, or an alkoxy group having 1 to 6 carbon atoms. The MQ resin (E) does not contain any alkenyl groups, or contains alkenyl groups in such an amount that the total amount of alkenyl groups in the organopolysiloxane resin is less than 0.005 mol / 100 g.

[0022] Preferably, the organopolysiloxane resin (MQ resin) comprises the component (B) and, optionally, at least one MQ resin selected from the components (E) and (F). More preferably, the organopolysiloxane resin comprises the components (B) and (F), and, optionally, the component (E).

[0023] A preferred embodiment of the silicone pressure-sensitive adhesive composition (II) is a silicone pressure-sensitive adhesive composition containing a condensation reaction product of the component (A), optionally the component (A'), and the component (B). More preferably, it is a silicone pressure-sensitive adhesive composition containing a condensation reaction product of the component (A), optionally the component (A'), the component (B), and optionally at least one MQ resin selected from the components (E) and (F).

[0024] Another preferred embodiment of the present invention is a silicone pressure-sensitive adhesive composition comprising a condensation reaction product of the above-mentioned component (A), optionally the above-mentioned component (A'), the above-mentioned component (B), and the above-mentioned component (F). Another preferred embodiment of the present invention is a silicone pressure-sensitive adhesive composition comprising the component (A), optionally a condensation reaction product of the component (A') and the component (B), and the component (F). Another preferred embodiment of the present invention is a silicone pressure-sensitive adhesive composition comprising a condensation reaction product of the above-mentioned component (A), optionally the above-mentioned component (A'), the above-mentioned component (B), and the above-mentioned component (E). Another more preferred embodiment of the present invention is a silicone pressure-sensitive adhesive composition comprising a condensation reaction product of the above-mentioned component (A), optionally the above-mentioned component (A'), the above-mentioned component (B), the above-mentioned component (E), and the above-mentioned component (F). Another more preferred embodiment of the present invention is a silicone pressure-sensitive adhesive composition comprising the component (A), optionally the component (A'), the component (B), and a condensation reaction product of the component (E), and the component (F).

[0025] Each component will be described in more detail below.

[0026] [Component (A)] Component (A) is a linear organopolysiloxane having one or more alkenyl groups per molecule. Component (A) may be any linear organopolysiloxane having one or more alkenyl groups per molecule, and may be used alone or in combination of two or more types.

[0027] Component (A) may be any oil- or gum-like organopolysiloxane, preferably a gum-like organopolysiloxane. The viscosity at 25°C of oil-like organopolysiloxanes is preferably 1,000 mPa·s or more, more preferably 10,000 mPa·s or more, and particularly preferably 50,000 mPa·s or more. For gum-like organopolysiloxanes, the viscosity of a 30% by mass solution in toluene is preferably 1,000 to 200,000 mPa·s, more preferably 5,000 to 150,000 mPa·s, even more preferably 10,000 to 120,000 mPa·s, and particularly preferably 15,000 to 100,000 mPa·s. Viscosities below the lower limit may make uniform coating difficult or may result in reduced adhesive strength and storage modulus G' of the resulting adhesive layer. If the viscosity exceeds the upper limit, the viscosity of the composition will be so high that it may be difficult to stir and mix, resulting in poor workability. In this specification, viscosity (mPa s) is a value measured at 25°C using a B-type rotational viscometer in accordance with JIS K 7117-1 (the same applies hereinafter).

[0028] The amount of alkenyl groups contained in component (A) is preferably 0.0001 to 0.03 mol per 100 g of organopolysiloxane, more preferably 0.0002 to 0.02 mol / 100 g, more preferably 0.0003 to 0.01 mol / 100 g, and even more preferably 0.0005 to 0.005 mol / 100 g. If the amount is less than the lower limit, the curability may decrease, and the storage modulus G' and adhesive strength of the resulting adhesive layer may decrease. If the amount is more than the upper limit, the crosslink density of the resulting adhesive layer may increase, and adhesive strength may decrease. This amount of alkenyl groups is determined by the amount of the deuterated chloroform solution. 1 H-NMR and 29 It can be determined by a known structural analysis method using Si-NMR (the same applies hereinafter).

[0029] Component (A) optionally contains silicon-bonded hydroxyl groups or alkoxy groups having 1 to 6 carbon atoms. When component (A) contains hydroxyl groups, the ratio of the number of hydroxyl groups and alkoxy groups to the total number of silicon-bonded groups in the organopolysiloxane is preferably 10% or less, more preferably 0.001 to 5%, and even more preferably 0.002 to 1%. That is, the amount of hydroxyl groups and alkoxy groups in component (A) is preferably 0.00002 to 0.15 mol / 100 g, and particularly preferably 0.00005 to 0.03 mol / 100 g. The presence of hydroxyl groups or alkoxy groups enables component (A) to undergo a condensation reaction with component (B) and optional components (E) and (F), which will be described later. The amount of SiOH groups is determined by the amount of the hydroxyl groups in a deuterated chloroform solution. 1 H-NMR and 29 This can be determined by a known structural analysis method using Si-NMR (the same applies hereinafter). The alkoxy group is preferably an alkoxy group having 1 to 6 carbon atoms, and examples thereof include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, and a phenoxy group.

[0030] The organopolysiloxane (A) is preferably represented by the following formula (1): [ka] In the formula, R 1 are each independently a hydroxyl group, an alkoxy group having 1 to 6 carbon atoms, or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, provided that R 1 at least one of the groups is an alkenyl-containing organic group having 2 to 10 carbon atoms, and a is a positive number such that a solution of the organopolysiloxane in toluene to a concentration of 30% by mass has a viscosity of 1,000 to 200,000 mPa·s at 25°C.

[0031] In formula (1), R 1 are each independently a hydroxyl group, an alkoxy group having 1 to 6 carbon atoms, or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, and R 1At least one of the alkenyl-containing organic groups has 2 to 10 carbon atoms. The alkenyl-containing organic group has 2 to 10 carbon atoms, preferably 2 to 8 carbon atoms, and may contain an oxygen atom. Examples include alkenyl groups such as vinyl, allyl, hexenyl, and octenyl, and cycloalkenylalkyl groups such as cyclohexenylethyl. Examples of alkenyl-containing monovalent hydrocarbon groups that may contain an oxygen atom include acryloylalkyl groups and methacryloylalkyl groups such as acryloylpropyl, acryloylmethyl, methacryloylpropyl, and methacryloylmethyl. The methylene chain may also contain an ether bond, such as -(CH2)2-O-CH2-CH=CH2 or -(CH2)3-O-CH2-CH=CH2.

[0032] The monovalent hydrocarbon group other than the alkenyl group-containing organic group is a monovalent hydrocarbon group having 1 to 10 carbon atoms and no aliphatic unsaturated bond. Examples include alkyl groups preferably having 1 to 6 carbon atoms, such as methyl, ethyl, propyl, and butyl; cycloalkyl groups preferably having 5 to 8 carbon atoms, such as cyclohexyl; aryl groups preferably having 6 to 10 carbon atoms, such as phenyl and tolyl; aralkyl groups preferably having 7 to 10 carbon atoms, such as benzyl; and monovalent hydrocarbon groups having 1 to 10 carbon atoms in which some or all of the hydrogen atoms bonded to carbon atoms have been substituted with hydroxy groups, cyano groups, halogen atoms, alkoxy groups, alkoxysilyl groups, polyoxyalkylene groups, epoxy groups, carboxyl groups, or the like, such as hydroxypropyl, cyanoethyl, 3-chloropropyl, 3,3,3-trifluoropropyl, 3,3,4,4,5,5,6,6,6-nonafluorohexyl, methoxypropyl, ethoxypropyl, and γ-glycidoxypropyl groups. Among these, a methyl group or a phenyl group is preferred, and a methyl group is particularly preferred. 1 It is particularly preferred that the ratio of the number of methyl groups to the total number of R is 70% or more, preferably 80% or more, and more preferably 90% or more. 1 When R 1The ratio of the total number of aryl groups and aralkyl groups to the total number of (a) and (b) is preferably 0.1 to 30%, more preferably 0.5 to 15%. When an aryl group or an aralkyl group is contained, the adhesive strength and storage modulus G' of the resulting adhesive layer may be improved.

[0033] When the above formula (1) has a hydroxyl group or an alkoxy group, R 1 The ratio of the number of hydroxyl groups and alkoxy groups to the total number of groups is preferably 10% or less, more preferably 0.001 to 5%, and even more preferably 0.002 to 1%. That is, the amount of hydroxyl groups and alkoxy groups in component (A) is preferably 0.00002 to 0.15 mol / 100g, and particularly preferably 0.00005 to 0.03 mol / 100g. By having hydroxyl groups or alkoxy groups, component (A) can undergo a condensation reaction with component (B) and optional components (E) and (F), which will be described later. The amount of SiOH groups is determined by the amount of the hydroxyl group in the deuterated chloroform solution. 1 H-NMR and 29 It can be determined by a known structural analysis method using Si-NMR (the same applies hereinafter).

[0034] In formula (1), a is preferably 100 to 20,000, more preferably 500 to 15,000, even more preferably 1,000 to 13,500, and even more preferably 2,000 to 12,000. If a is less than the above lower limit, uniform coating may be difficult, and the adhesive strength and storage modulus G' of the resulting adhesive layer may decrease. If a exceeds the above upper limit, the viscosity of the composition may become very high, making it difficult to stir and mix, and other workability problems may result.

[0035] Component (A) is preferably a crude rubber-like organopolysiloxane represented by the following formula (2). [ka] In the formula, R 2 are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms that does not have a hydroxyl group or an aliphatic unsaturated bond, and R 2’is an alkyl group having 1 to 6 carbon atoms, X is an alkenyl-containing organic group having 2 to 10 carbon atoms, b is a number from 1 to 3, c is a number from 1 to 3, d is a number from 0 to 2, e is a number from 0 to 2, f is a number from 0 to 2, g is a number from 0 to 2, d+e+f+g=2, h is a number of 0 or greater, c×f+h≧1, i is a number of 100 or greater, and h+i is a positive number such that the organopolysiloxane has the above-mentioned viscosity. More preferably, 100≦h+i≦20,000.

[0036] In formula (2), R 2 are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms that does not have a hydroxyl group or an aliphatic unsaturated bond. For example, R 1 Examples of monovalent hydrocarbon groups other than the alkenyl-containing organic groups exemplified by R include those mentioned above. Among these, a methyl group or a phenyl group is preferred, and a methyl group is particularly preferred. 2 If it contains a hydroxyl group, R 2 The ratio of the number of hydroxyl groups to the total number of groups is preferably 10% or less, more preferably 0.001 to 5%, and even more preferably 0.002 to 1%.

[0037] X is an alkenyl-containing monovalent organic group having 2 to 10 carbon atoms, preferably 2 to 8 carbon atoms, and may contain an oxygen atom. 1 Examples of the alkenyl group-containing organic group include those mentioned above. Among them, a vinyl group is preferred.

[0038] In formula (2), b is a number from 1 to 3, preferably 1. c is a number from 1 to 3, preferably 1. d is a number from 0 to 2, preferably 0 to 1.5, and more preferably 0 to 1.0. e is a number from 0 to 2, preferably 0 to 1, more preferably 0 to 0.5, and even more preferably 0. f is a number from 0 to 2, preferably 0.5 to 2, and more preferably 1.0 to 2. g is a number from 0 to 2, preferably 0 to 1.5, more preferably 0 to 1.0, and even more preferably 0. h is a number of 0 or more, preferably 0 to 500, more preferably 0 to 100, and even more preferably 0 to 50. i is a number of 100 or more, preferably 500 to 15,000, more preferably 1,000 to 13,500, and even more preferably 2,000 to 12,000. c×f+h is 2 or more, preferably 2 to 500, more preferably 2 to 100, and even more preferably 2 to 50. h+i is 100 to 20,000, preferably 500 to 15,000, more preferably 1,000 to 13,500, and even more preferably 2,000 to 12,000.

[0039] Examples of component (A) include, but are not limited to, the following: In the following formulae, Me, Vi, and Ph represent a methyl group, a vinyl group, and a phenyl group, respectively. The bonding order of each siloxane unit shown in parentheses is not limited to the following. In each of the following formulae, the total number of siloxane repeating units is an average value. [ka] (z1+z2+z3+z4+z5=2, and z6, z7, and z8 are numbers at which the organopolysiloxane has the above-mentioned viscosity. Preferably, 100≦z6+z7+z8≦20,000.) [ka] (z6 is the number at which the organopolysiloxane has the above-mentioned viscosity. Preferably, 100≦z6≦20,000.) [ka] (z6 and z7 are numbers at which the organopolysiloxane has the above-mentioned viscosity. Preferably, 100≦z6+z7≦20,000.) [ka] (z6 is the number at which the organopolysiloxane has the above-mentioned viscosity. Preferably, 100≦z6≦20,000.) [ka] (z6 and z7 are numbers at which the organopolysiloxane has the above-mentioned viscosity. Preferably, 100≦z6+z7≦20,000.) [ka] (z8≧1, z6 and z8 are numbers at which the organopolysiloxane has the above-mentioned viscosity. Preferably, 100≦z6+z8≦20,000.) [ka] (z8≧1, z6, z7, and z8 are numbers at which the organopolysiloxane has the above-mentioned viscosity. Preferably, 100≦z6+z7+z8≦20,000.) [ka] (z1 + z5 = 2, z8 ≥ 1, z6 and z8 are numbers that allow the organopolysiloxane to have the above-mentioned viscosity. Preferably, 100 ≤ z6 + z8 ≤ 20,000.) [ka] (z1 + z5 = 2, z8 ≥ 1, z6, z7, and z8 are numbers that allow the organopolysiloxane to have the above-mentioned viscosity. Preferably, 100 ≤ z6 + z7 + z8 ≤ 20,000.) [ka] (z1 + z3 = 2, z3 + z8 ≥ 1, z6 and z8 are numbers that allow the organopolysiloxane to have the above-mentioned viscosity. Preferably, 100 ≤ z6 + z8 ≤ 20,000.) [ka] (z1 + z3 = 2, z3 + z8 ≥ 1, z6, z7, and z8 are numbers that allow the organopolysiloxane to have the above-mentioned viscosity. Preferably, 100 ≤ z6 + z7 + z8 ≤ 20,000.) [ka] (z1 + z4 = 2, z4 × 3 + z8 ≥ 1, z6 and z8 are numbers that allow the organopolysiloxane to have the above-mentioned viscosity. Preferably, 100 ≤ z6 + z8 ≤ 20,000.) [ka] (z1 + z4 = 2, z4 × 3 + z8 ≥ 1, z6, z7, and z8 are numbers that allow the organopolysiloxane to have the above-mentioned viscosity. Preferably, 100 ≤ z6 + z7 + z8 ≤ 20,000.) [ka] (z1 + z2 = 2, z8 ≥ 1, z6 and z8 are numbers that allow the organopolysiloxane to have the above-mentioned viscosity. Preferably, 100 ≤ z6 + z8 ≤ 20,000.) [ka] (z1 + z2 = 2, z8 ≥ 1, z6, z7, and z8 are numbers that allow the organopolysiloxane to have the above-mentioned viscosity. Preferably, 100 ≤ z6 + z7 + z8 ≤ 20,000.)

[0040] The silicone composition of the present invention may further contain, as the linear organopolysiloxane, a linear organopolysiloxane (A') that does not have an alkenyl group or an SiH group. When the organopolysiloxane (A') has an SiOH group or an alkoxysilyl group, it can undergo a condensation reaction with the (B) component and optional (E) and (F) components described below. The content of the (A') component, based on the total mass of the (A) and (A') components, is preferably 70% by mass or less, more preferably 50% by mass or less, and even more preferably 40% by mass or less. Within the above range, the adhesive strength and storage modulus G' of the resulting adhesive layer may be improved. The lower limit of the content of the (A') component relative to the total mass of the (A) and (A') components is not particularly limited, and may be 0% by mass or more. For example, the content may be 0.1% by mass or more, 1% by mass or more, etc.

[0041] The component (A') is represented, for example, by the following formula (1'). [ka] (In the formula, R 1’ are each independently a hydroxyl group, an alkoxy group having 1 to 6 carbon atoms, or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, provided that R 1’ is not an alkenyl-containing organic group, and a' is a positive number of 1 or more.

[0042] Component (A') may be an oily or crude rubber organopolysiloxane. Its viscosity at 25°C is preferably 1,000 mPa·s or higher, more preferably 10,000 mPa·s or higher, and particularly preferably 50,000 mPa·s or higher. For crude rubber-like organopolysiloxanes, the viscosity of a 30% by mass solution in toluene is preferably 1,000 to 200,000 mPa·s, more preferably 5,000 to 150,000 mPa·s, even more preferably 10,000 to 120,000 mPa·s, and particularly preferably 15,000 to 100,000 mPa·s.

[0043] In formula (1'), a' is a positive number of 1 or greater, and may be any value that allows the organopolysiloxane to have the above-mentioned viscosity. Preferably, a' is 100 to 20,000, more preferably 500 to 15,000, more preferably 1,000 to 13,500, and even more preferably 2,000 to 12,000. R 1’ For example, R 1 Examples of monovalent hydrocarbon groups other than the alkenyl-containing organic groups exemplified by R include those mentioned above. Among these, a methyl group or a phenyl group is preferred, and a methyl group is particularly preferred. 1’ When R contains a hydroxyl group or an alkoxy group, 1’ The ratio of the number of hydroxyl groups and alkoxy groups to the total number of groups is preferably 10% or less, more preferably 0.001 to 5%, and even more preferably 0.002 to 1%.

[0044] [(B) Component] (B) component is R 3 3SiO 1 / 2 Units and SiO 4 / 2 Contains the unit R 3 3SiO 1 / 2 Units / SiO 4 / 2 The organopolysiloxane resin has a molar ratio of units of 0.5 to 1.5, preferably 0.55 to 1.3, and more preferably 0.6 to 1.0. If the molar ratio is less than the lower limit or exceeds the upper limit, the adhesive strength and storage modulus G' of the resulting adhesive layer may decrease. 3 3SiO 1 / 2 Units / SiO 4 / 2 The molar ratio of the unit is that of a deuterated chloroform solution. 1 H-NMR and 29 This can be determined by a known structural analysis method using Si-NMR (the same applies hereinafter). The component (B) may be used alone or in combination of two or more.

[0045] The organopolysiloxane resin (B) can undergo a condensation reaction with the component (A) and, optionally, the components (A'), (E), and (F).

[0046] R 3are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, a hydroxyl group, or an alkoxy group having 1 to 6 carbon atoms. Examples include alkyl groups preferably having 1 to 6 carbon atoms, such as methyl, ethyl, propyl, and butyl; cycloalkyl groups preferably having 5 to 8 carbon atoms, such as cyclohexyl; aryl groups preferably having 6 to 10 carbon atoms, such as phenyl and tolyl; aralkyl groups preferably having 7 to 10 carbon atoms, such as benzyl; alkenyl groups preferably having 2 to 8 carbon atoms, such as vinyl, allyl, and hexenyl; and monovalent hydrocarbon groups having 1 to 10 carbon atoms in which some or all of the hydrogen atoms bonded to carbon atoms of the hydrocarbon groups have been substituted with hydroxy groups, cyano groups, halogen atoms, alkoxy groups, alkoxysilyl groups, polyoxyalkylene groups, epoxy groups, carboxyl groups, or the like, such as hydroxypropyl, cyanoethyl, 3-chloropropyl, 3,3,3-trifluoropropyl, 3,3,4,4,5,5,6,6,6-nonafluorohexyl, methoxypropyl, ethoxypropyl, and γ-glycidoxypropyl groups. Of these, methyl and phenyl groups are preferred, with methyl being particularly preferred.

[0047] Component (B) may contain or not contain alkenyl groups, but the total amount of alkenyl groups contained in the resin is less than 0.005 mol / 100 g, more preferably less than 0.004 mol / 100 g, and even more preferably less than 0.003 mol / 100 g. Component (B) most preferably does not contain alkenyl groups. If the alkenyl group content of component (B) exceeds the upper limit, the adhesive strength and storage modulus G' of the resulting adhesive layer may decrease.

[0048] (B) component is R 3 3SiO 1 / 2 Units and SiO 4 / 2 Although the organopolysiloxane resin is essentially composed of R units, it may contain R units within a range that does not impair the properties of the present invention. 3 2SiO 2 / 2 Units and R 3 SiO 3 / 2 Units (R 3is as described above). More preferably, the above R 3 3SiO 1 / 2 Units and above SiO 4 / 2 It is an organopolysiloxane resin consisting of units.

[0049] Component (B) may have either or both of a siloxane unit having a hydroxyl group bonded to a silicon atom (silanol group-containing unit) and a siloxane unit having an alkoxy group having 1 to 6 carbon atoms bonded to a silicon atom (alkoxy group-containing unit). The amount of silanol group-containing units is preferably such that the hydroxyl group content is 0.005 to 0.3 mol / 100 g of component (B), more preferably 0.008 to 0.25 mol / 100 g, and even more preferably 0.01 to 0.2 mol / 100 g. If the hydroxyl group content exceeds 0.3 mol / 100 g, the adhesive strength and storage modulus G' of the resulting adhesive layer may decrease, or the curability may decrease. The amount of alkoxy group-containing units is preferably such that the content of the alkoxy groups is 0.3 mol / 100 g or less of component (B), more preferably 0.2 mol / 100 g or less, and even more preferably 0.1 mol / 100 g or less. If the alkoxy group content exceeds 0.3 mol / 100 g, the adhesive strength and storage modulus of the resulting adhesive layer may decrease, or the curing properties may decrease. There is no lower limit, but it can be, for example, 0.003 mol / 100 g or more. The above SiOH group amount and alkoxy group content are determined by the concentration of the alkoxy group in the deuterated chloroform solution. 1 H-NMR and 29 It can be determined by a known structural analysis method using Si-NMR (the same applies hereinafter).

[0050] Furthermore, the total amount of the silanol group-containing units and alkoxy group-containing units, as the sum of the hydroxyl group content and alkoxy group content, in component (B) is preferably 0.008 to 0.3 mol / 100 g, more preferably 0.01 to 0.25 mol / 100 g, and particularly preferably 0.02 to 0.2 mol / 100 g. The presence of the hydroxyl group or the alkoxy group enables condensation reactions with component (A) and optional components (A'), (E), and (F).

[0051] Examples of the alkoxy group having 1 to 6 carbon atoms include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, and a phenoxy group. The silanol group-containing unit is a unit represented by R 3 2(OH)SiO 1 / 2 Units, R 3 (OH)2SiO 1 / 2 Units, R 3 (OH)SiO 2 / 2 Units: (OH)SiO 3 / 2 The alkoxy group-containing unit is, for example, R 3 2(OR')SiO 1 / 2 Units, R 3 (OR')2SiO 1 / 2 Units, R 3 (OR')SiO 2 / 2 Units: (OR')SiO 3 / 2 (OR' are each independently an alkoxy group having 1 to 6 carbon atoms, as exemplified above). 3 3SiO 1 / 2 Units and SiO 4 / 2 When the unit is SiO 4 / 2 It can be bonded to a silicon atom from the unit.

[0052] Component (B) is an organopolysiloxane resin having a weight-average molecular weight of 5,000 or more. The weight-average molecular weight is more preferably 5,300 to 15,000, more preferably 5,600 to 12,000, even more preferably 6,000 to 10,000, and most preferably 6,500 to 10,000. If the weight-average molecular weight is below the lower limit or exceeds the upper limit, the adhesive strength and storage modulus G' of the resulting adhesive layer may decrease. The weight-average molecular weight can be determined as the weight-average molecular weight converted into polystyrene by gel permeation chromatography (GPC) analysis using toluene as the developing solvent.

[0053] In the present invention, the weight average molecular weight (Mw) is a value determined by GPC (gel permeation chromatography) analysis using polystyrene as a standard substance under the following conditions. (Measurement conditions) GPC measuring device: HLC-8320 (Tosoh Corporation) Detector: Refractive index detector (RI) Measurement solvent: toluene Flow rate: 0.35mL / min GPC columns: (passed in the following order) TSKgel Guardcolumn SuperHZ-L(4.6mmI.D.×2cm×1) TSKgel SuperHZ4000(4.6mmI.D.×15cm×1) TSKgel SuperHZ3000(4.6mmI.D.×15cm×1) TSKgel SuperHZ2000 (4.6mm I.D. x 15cm x 2) (both manufactured by Tosoh Corporation) Measurement temperature: 40℃ Sample injection volume: 10 μL (toluene solution with a silicone concentration of 0.5 wt%)

[0054] [(C) component] Component (C) is an organohydrogenpolysiloxane having three or more silicon-bonded hydrogen atoms (SiH groups) per molecule, and the organohydrogenpolysiloxane (C) may be used alone or in combination of two or more different types.

[0055] The average degree of polymerization of the siloxane of component (C) is preferably 100 or less, more preferably 3-80, more preferably 4-70, more preferably 5-50, and even more preferably 6-30.

[0056] The SiH groups in component (C) undergo an addition reaction with the alkenyl groups in component (A) and component (F), described below, to cure and form an adhesive layer. The amount of component (C) added is such that the ratio of the total number of SiH groups in component (C) to the total number of alkenyl groups in the alkenyl-group-containing organopolysiloxane contained in the silicone adhesive composition is 0.1 to 30.0, preferably 0.2 to 20.0, more preferably 0.3 to 15.0, more preferably 0.3 to 10.0, even more preferably 0.4 to 5.0, and even more preferably 0.5 to 2.0. The lower limit is preferably 0.75 or greater. That is, the ratio of the total number of SiH groups in component (C) to the total number of alkenyl groups in component (A) and optional component (F) is 0.1 to 30.0, preferably 0.2 to 20.0, more preferably 0.3 to 15.0, more preferably 0.3 to 10.0, even more preferably 0.4 to 5.0, and even more preferably 0.5 to 2.0. An especially preferred lower limit is 0.75 or higher. The amount of component (C) blended is preferably 0.01 to 10.0 parts by mass, more preferably 0.05 to 7.0 parts by mass, and even more preferably 0.10 to 5.0 parts by mass, per 100 parts by mass of the total of components (A), (B), and optional components (A'), (E), and (F).

[0057] The blending amount of component (C) is preferably 0.00005 to 10 mass%, more preferably 0.00010 to 7.0 mass%, and even more preferably 0.00050 to 5.0 mass%, based on the total amount of the silicone pressure-sensitive adhesive composition including the optional components described below. If the blending amount or number ratio is less than the above lower limit, the adhesive strength and storage modulus G' of the resulting adhesive layer may decrease. If the blending amount or number ratio exceeds the above upper limit, the adhesive strength of the resulting adhesive layer may decrease, or the usable time of the treatment bath may be shortened.

[0058] The component (C) may be linear, branched, or cyclic, or may be a mixture thereof. Examples of the component (C) include R 4 2HSiO 1 / 2 Units, R 4 HSiO 2 / 2 units, and HSiO 3 / 2 and optionally further comprising at least one R 4 3SiO 1 / 2 Units, R 4 2SiO 2 / 2 Units, R 4 SiO 3 / 2 units, and SiO 4 / 2 Examples include polymers or copolymers comprising at least one of the units 4 are each independently a hydroxyl group, an alkoxy group having 1 to 6 carbon atoms, or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms and no aliphatic unsaturated bond. 4 2HSiO 1 / 2 Unit or R 4 HSiO 2 / 2 It is preferable that the total number of units in one molecule is 3 to 100, preferably 4 to 70, more preferably 5 to 50, and even more preferably 6 to 30. If the number of SiH groups is less than the above lower limit or exceeds the above upper limit, the curability may decrease, and the adhesive strength and storage modulus G' of the resulting adhesive layer may decrease.

[0059] The above R 4are each independently a hydroxyl group, an alkoxy group having 1 to 6 carbon atoms, or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms and no aliphatic unsaturated bond. Examples of monovalent hydrocarbon groups include alkyl groups preferably having 1 to 6 carbon atoms, such as methyl, ethyl, propyl, and butyl; cycloalkyl groups preferably having 5 to 8 carbon atoms, such as cyclohexyl; aryl groups preferably having 6 to 10 carbon atoms, such as phenyl and tolyl; aralkyl groups preferably having 7 to 10 carbon atoms, such as benzyl; and monovalent hydrocarbon groups having 1 to 10 carbon atoms in which some or all of the hydrogen atoms bonded to carbon atoms have been substituted with hydroxy groups, cyano groups, halogen atoms, alkoxy groups, alkoxysilyl groups, polyoxyalkylene groups, epoxy groups, carboxyl groups, and the like, such as hydroxypropyl, cyanoethyl, 3-chloropropyl, 3,3,3-trifluoropropyl, 3,3,4,4,5,5,6,6,6-nonafluorohexyl, methoxypropyl, ethoxypropyl, and γ-glycidoxypropyl groups. Among these, R 4 is preferably an alkyl group or an aryl group, and more preferably a methyl group, an ethyl group, a propyl group or a phenyl group. 4 may be a hydroxyl group, but R 4 The ratio of the number of hydroxyl groups to the total number of groups is preferably 10% or less, more preferably 5% or less, and even more preferably 1% or less. There is no lower limit, but the fewer the number of hydroxyl groups in component (C), the better, and component (C) may not contain any hydroxyl groups.

[0060] Component (C) has a viscosity of 1 to 2,000 mPa·s, and preferably 2 to 1,000 mPa·s at 25° C. If the viscosity is below the lower limit or above the upper limit, the curing properties may be reduced, and the adhesive strength and storage modulus G' of the resulting adhesive layer may be reduced.

[0061] Component (C) is preferably a linear organohydrogenpolysiloxane represented by the following formula (4). [ka] (In the formula, R 4are each independently a hydroxyl group, an alkoxy group having 1 to 6 carbon atoms, or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms and no aliphatic unsaturated bonds. j is 0 to 1, k and m are numbers such that 1≦k≦98 and 0≦m≦60, and 3≦2j+k≦100 and 3≦k+m+2≦100.

[0062] In the above formula (4), R 4 are each independently a hydroxyl group, an alkoxy group having 1 to 6 carbon atoms, or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms and no aliphatic unsaturated bond, as defined above. 4 is preferably an alkyl group or an aryl group, and more preferably a methyl group, an ethyl group, a propyl group, or a phenyl group. 4 may be a hydroxyl group, but R 6 The ratio of the number of hydroxyl groups to the total number of groups is preferably 10% or less, more preferably 5% or less, and even more preferably 1% or less. There is no lower limit, but the smaller the amount of hydroxyl groups, the better, and it is not necessary for the polymer to contain any hydroxyl groups.

[0063] With regard to j, k, and m, k is a number from 1 to 98, preferably 3 to 80, more preferably 4 to 70, more preferably 5 to 50, and even more preferably 6 to 30. m is a number from 0 to 60, preferably 0 to 30, more preferably 0 to 20, and even more preferably 0 to 10. j is 0 or 1, and 2j+k is 3 to 100, preferably 4 to 70, more preferably 5 to 50, and even more preferably 6 to 30. k+m+2 is 3 to 100, preferably 4 to 70, more preferably 5 to 50, and even more preferably 6 to 30.

[0064] In addition, the hydrogen atom bonded to the silicon atom and the group R bonded to the silicon atom 4The ratio of the total number of hydrogen atoms bonded to silicon atoms to the total number of hydrogen atoms (hereinafter referred to as the ratio of SiH groups) is preferably 20 to 50%, more preferably 25 to 49%, and even more preferably 30 to 48%. If the ratio of SiH groups is less than the above lower limit or exceeds the above upper limit, the curability may decrease, and the adhesive strength and storage modulus G' of the resulting adhesive layer may decrease.

[0065] Examples of component (C) include, but are not limited to, the following: In the following formulae, Me and Ph represent a methyl group and a phenyl group, respectively. The bonding order of each siloxane unit shown in parentheses is not limited to the following: In each of the following formulae, the total number of siloxane repeating units is an average value. [ka] (5≦z9+2≦100) [ka] (3≦z10+2≦100) [ka] (3≦z11≦97, 1≦z12≦60, 6≦z11+z12+2≦100, and the ratio of SiH groups is 20% to 50%.) [ka] (1≦z13≦97, 1≦z14≦60, 4≦z13+z14+2≦100, and the ratio of SiH groups is 20% to 50%.) [ka] (These numbers satisfy the conditions of 0≦z15, 0≦z16, 0≦z17, 3≦z18, and 1≦z19, the proportion of SiH groups is 20% to 50%, and the average degree of polymerization of siloxane is 100 or less.) [ka] (The numbers satisfy the conditions of 0≦z20, 0≦z21, 0≦z22, 3≦z23, and 1≦z24, the proportion of SiH groups is 20% to 50%, and the average degree of polymerization of siloxane is 100 or less.) [ka] (These numbers satisfy the conditions of 0≦z25, 0≦z26, 0≦z27, 3≦z28, 1≦z29, and 1≦z30, the proportion of SiH groups is 20% to 50%, and the average degree of polymerization of siloxane is 100 or less.) [ka] (3≦z31≦97, 1≦z32≦60, 6≦z31+z32+2≦100, and the ratio of SiH groups is 20% to 50%.) [ka] (These numbers satisfy the conditions of 1≦z33≦97, 1≦z34≦60, and 4≦z33+z34+2≦100, and the proportion of SiH groups is 20% to 50%.) [ka] (3≦z35≦97, 1≦z36≦60, 6≦z35+z36+2≦100, and the ratio of SiH groups is 20% to 50%.) [ka] (3≦z37≦96, 1≦z38≦60, 1≦z39≦60, 7≦z37+z38+z39+2≦100, and the ratio of SiH groups is 20% to 50%.) [ka] (These numbers satisfy the conditions of 1≦z40≦96, 1≦z41≦60, 1≦z42≦60, and 5≦z40+z41+z42+2≦100, and the proportion of SiH groups is 20% to 50%.)

[0066] [(D) component] Component (D) is a catalyst for promoting the addition reaction between component (A) and optional component (F), described below, and component (C). Any catalyst that promotes the so-called hydrosilylation reaction can be used, and known platinum group metal catalysts can be used. Examples of platinum group metal catalysts include platinum-based, palladium-based, rhodium-based, ruthenium-based, and iridium-based catalysts, with platinum catalysts being particularly preferred. Examples of platinum catalysts include chloroplatinic acid, alcoholic or aldehyde solutions of chloroplatinic acid, reaction products of chloroplatinic acid with alcohols, and complexes of chloroplatinic acid or platinum with various olefins or vinylsiloxanes. Component (D) may be used alone or in combination.

[0067] The amount of component (D) to be added may be a catalytic amount. The catalytic amount is an amount effective for promoting the addition reaction with component (A), optional component (F), and component (C). To obtain a good adhesive layer, the amount is 1 to 5,000 ppm, preferably 5 to 500 ppm, and particularly preferably 10 to 200 ppm, calculated as platinum group metal mass relative to the total mass of components (A), (B), (C), and optional components (A'), (E), and (F). If the amount is less than 1 ppm, the curability may be reduced, or the crosslink density of the resulting adhesive layer may be low, resulting in reduced adhesive strength and storage modulus G'. If the amount exceeds 5,000 ppm, the usable time of the treatment bath may be shortened.

[0068] [(E) component] The silicone pressure-sensitive adhesive composition of the present invention is 3 3SiO 1 / 2 Units and SiO 4 / 2 units and has hydroxyl groups and / or alkoxy groups having 1 to 6 carbon atoms bonded to silicon atoms, (R 3 3SiO 1 / 2 Unit) / (SiO 4 / 2The silicone pressure-sensitive adhesive composition may further contain an organopolysiloxane resin having a molar ratio, expressed as a mol / mol ratio (R / R units), of 0.5 to 1.5 and a weight average molecular weight (Mw) of less than 5,000 as measured by gel permeation chromatography (GPC) relative to standard polystyrene standards, in an amount of 0.01 to 35 mass % relative to the total mass of the silicone pressure-sensitive adhesive composition. 3 are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, a hydroxyl group, or an alkoxy group having 1 to 6 carbon atoms. The organopolysiloxane resin does not contain alkenyl groups, or contains alkenyl groups in such an amount that the total amount of alkenyl groups in the organopolysiloxane resin is less than 0.005 mol / 100 g.

[0069] (E) component is R 3 3SiO 1 / 2 Units and SiO 4 / 2 Contains the unit R 3 3SiO 1 / 2 Units / SiO 4 / 2 The organopolysiloxane resin has a molar ratio of units of 0.5 to 1.5, preferably 0.55 to 1.3, and more preferably 0.6 to 1.0. If the molar ratio is less than the above lower limit or exceeds the above upper limit, the adhesive strength and storage modulus G' of the resulting adhesive layer may decrease. The component (E) may be used alone or in combination of two or more types.

[0070] The organopolysiloxane resin (E) can undergo a condensation reaction with components (A), (B), and optionally components (A') and (F).

[0071] R 3 are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, a hydroxyl group, or an alkoxy group having 1 to 6 carbon atoms. For example, 1 Among them, methyl group and phenyl group are preferred, and methyl group is particularly preferred.

[0072] Component (E) may contain or not contain alkenyl groups, but the total amount of alkenyl groups contained in the resin is less than 0.005 mol / 100 g, more preferably less than 0.004 mol / 100 g, and even more preferably less than 0.003 mol / 100 g. Component (E) most preferably does not contain alkenyl groups. If the amount exceeds the upper limit, the adhesive strength and storage modulus G' of the resulting adhesive layer may decrease.

[0073] (E) component is R 3 3SiO 1 / 2 Units and SiO 4 / 2 Although the organopolysiloxane resin is essentially composed of R units, it may contain R units within a range that does not impair the properties of the present invention. 3 2SiO 2 / 2 Units and R 3 SiO 3 / 2 Units (R 3 is as described above).

[0074] Component (E) may have a siloxane unit having a hydroxyl group bonded to a silicon atom (a silanol group-containing unit) or a siloxane unit having an alkoxy group having 1 to 6 carbon atoms bonded to a silicon atom (an alkoxy group-containing unit). The amount of silanol group-containing units is preferably such that the hydroxyl group content is 0.005 to 0.3 mol / 100 g of component (E), more preferably 0.008 to 0.25 mol / 100 g, and even more preferably 0.01 to 0.2 mol / 100 g. If the hydroxyl group content exceeds 0.3 mol / 100 g, the adhesive strength and storage modulus G' of the resulting adhesive layer may decrease, or the curability may decrease. The amount of alkoxy group-containing units is preferably such that the alkoxy group content of component (E) is 0.3 mol / 100 g or less, more preferably 0.2 mol / 100 g or less, and even more preferably 0.1 mol / 100 g or less. If the alkoxy group content exceeds 0.3 mol / 100 g, the adhesive strength and storage modulus G' of the resulting adhesive layer may decrease, or the curing properties may decrease. There is no lower limit, but it can be, for example, 0.003 mol / 100 g or more.

[0075] Furthermore, the total amount of the silanol group-containing units and alkoxy group-containing units, as the total of the hydroxyl group content and alkoxy group content, in component (E) is preferably 0.008 to 0.3 mol / 100 g, more preferably 0.01 to 0.25 mol / 100 g, and particularly preferably 0.02 to 0.2 mol / 100 g. By having hydroxyl groups or alkoxy groups in such amounts, the component (E) can undergo a condensation reaction with component (A), component (B), or optional component (A') or component (F).

[0076] Examples of the alkoxy group having 1 to 6 carbon atoms include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, and a phenoxy group. The silanol group-containing unit is a unit represented by R 3 2(OH)SiO 1 / 2 Units, R 3 (OH)2SiO 1 / 2 Units, R 3 (OH)SiO 2 / 2 Units: (OH)SiO 3 / 2 The alkoxy group-containing unit is, for example, R 3 2(OR')SiO 1 / 2 Units, R 3 (OR')2SiO 1 / 2 Units, R 3 (OR')SiO 2 / 2 Units: (OR')SiO 3 / 2 units (where OR' are each independently an alkoxy group having 1 to 6 carbon atoms, as exemplified above). 3 3SiO 1 / 2 Units and SiO 4 / 2 When the unit is SiO 4 / 2 It can be bonded to a silicon atom from the unit.

[0077] Component (E) has a weight-average molecular weight of less than 5,000. The weight-average molecular weight is preferably 500 to 4,750, and more preferably 1,000 to 4,500. The weight-average molecular weight (Mw) is a value determined by GPC (gel permeation chromatography) analysis using polystyrene as a standard substance under the conditions described above.

[0078] [Component (F)] The silicone pressure-sensitive adhesive composition of the present invention comprises (F) one or more alkenyl groups per molecule, the alkenyl group content being 0.005 to 0.5 mol / 100 g, and R 3 3SiO 1 / 2 Units and SiO 4 / 2 is an organopolysiloxane resin having units (R 3 3SiO 1 / 2 Unit) / (SiO 4 / 2 The silicone pressure-sensitive adhesive composition may contain the organopolysiloxane resin, which has a molar ratio (represented by the unit) of 0.5 to 1.5 and optionally has silicon-bonded hydroxyl groups and / or silicon-bonded alkoxy groups having 1 to 6 carbon atoms, in an amount of 0.01 to 45 mass % relative to the total mass of the silicone pressure-sensitive adhesive composition. 3 are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, a hydroxyl group, or an alkoxy group having 1 to 6 carbon atoms.

[0079] Component (F) has one or more alkenyl groups in one molecule, and R 3 3SiO 1 / 2 Units and SiO 4 / 2 Contains the unit R 3 3SiO 1 / 2 Units / SiO 4 / 2 The organopolysiloxane resin has a molar ratio of units of 0.5 to 1.5, preferably 0.55 to 1.3, and more preferably 0.6 to 1.0. If the molar ratio is less than the above lower limit or exceeds the above upper limit, the adhesive strength and storage modulus G' of the resulting adhesive layer may decrease. The component (F) may be used alone or in combination of two or more types.

[0080] The organopolysiloxane resin (F) can undergo a condensation reaction with components (A), (B), and optionally components (A') and (E).

[0081] R 3 are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, a hydroxyl group, or an alkoxy group having 1 to 6 carbon atoms. For example, 1 Among them, methyl group, phenyl group and vinyl group are preferred, and methyl group and vinyl group are particularly preferred.

[0082] Component (F) has 0.005 to 0.5 mol of alkenyl groups per 100 g of organopolysiloxane. The amount of alkenyl groups is preferably 0.01 to 0.3 mol / 100 g, more preferably 0.02 to 0.2 mol / 100 g, and even more preferably 0.05 to 0.16 mol / 100 g. If the amount is less than the above lower limit or exceeds the above upper limit, the adhesive strength and storage modulus G' of the resulting adhesive layer may decrease.

[0083] (F) component is R 3 3SiO 1 / 2 Units and SiO 4 / 2 Although the organopolysiloxane resin is essentially composed of R units, it may contain R units within a range that does not impair the properties of the present invention. 3 2SiO 2 / 2 Units and R 3 SiO 3 / 2 Units (R 3 and R 3 2SiO 2 / 2 It has units (R 3 2SiO 2 / 2 ) / (SiO 4 / 2 The molar ratio represented by the unit) is preferably 0.01 to 0.5, more preferably 0.02 to 0.4, even more preferably 0.03 to 0.3, and even more preferably 0.05 to 0.25.

[0084] More preferably, R 5 3SiO 1 / 2Units, R 5 2nd Round 6 SiO 1 / 2 units, and SiO 4 / 2 Organopolysiloxane resin consisting of units, or R 5 3SiO 1 / 2 Units, R 5 R 6 SiO 2 / 2 units, and SiO 4 / 2 Organopolysiloxane resins consisting of R units are preferred. 5 is the above R other than an alkenyl group. 3 and R 6 is an alkenyl group having 2 to 10 carbon atoms. 5 is the above R other than an alkenyl group. 3 R is a group represented by the formula: 6 Examples of the alkyl group include alkenyl groups having 2 to 10 carbon atoms, and vinyl groups are particularly preferred.

[0085] R 5 3SiO 1 / 2 Units, R 5 2nd Round 6 SiO 1 / 2 units, and SiO 4 / 2 In the organopolysiloxane resin consisting of units, the molar ratio of each unit is SiO 4 / 2 R for units (hereafter referred to as Q units) 5 3SiO 1 / 2 Units and R 5 2nd Round 6 SiO 1 / 2 It is sufficient that the molar ratio of units (hereinafter collectively referred to as M units) M units / Q units satisfies 0.5 to 1.5, preferably 0.55 to 1.3, and more preferably 0.6 to 1.0.

[0086] R 5 3SiO 1 / 2 Unit (hereinafter referred to as M unit), R 5 R 6 SiO 2 / 2 unit (hereinafter referred to as D unit), and SiO 4 / 2In an organopolysiloxane resin composed of units (hereinafter referred to as Q units), the molar ratios of the respective units, that is, the molar ratio of M units / Q units and the molar ratio of D units / Q units, may both be within the above-mentioned ranges. That is, the ratio of M units / Q units is 0.5 to 1.5, preferably 0.55 to 1.3, and preferably 0.6 to 1.0, and the ratio of D units / Q units is 0.01 to 0.5, more preferably 0.02 to 0.4, more preferably 0.03 to 0.3, and even more preferably 0.05 to 0.25. The molar ratios of M units / Q units and D units / Q units are determined by the molar ratios of the deuterated chloroform solution. 1 H-NMR and 29 It can be determined by a known structural analysis method using Si-NMR (the same applies hereinafter).

[0087] Component (F) may have a siloxane unit having a hydroxyl group bonded to a silicon atom (a silanol group-containing unit) or a siloxane unit having an alkoxy group having 1 to 6 carbon atoms bonded to a silicon atom (an alkoxy group-containing unit). The amount of silanol group-containing units is preferably such that the hydroxyl group content is 0.005 to 0.3 mol / 100 g of component (F), more preferably 0.008 to 0.2 mol / 100 g, and even more preferably 0.01 to 0.1 mol / 100 g. If the hydroxyl group content exceeds 0.3 mol / 100 g, the adhesive strength and storage modulus G' of the resulting adhesive layer may decrease, or the curability may decrease. The amount of alkoxy group-containing units is preferably such that the alkoxy group content of component (F) is 0.3 mol / 100 g or less, more preferably 0.2 mol / 100 g or less, and even more preferably 0.1 mol / 100 g or less. If the alkoxy group content exceeds 0.3 mol / 100 g, the adhesive strength and storage modulus G' of the resulting adhesive layer may decrease, or the curing properties may decrease. There is no lower limit, but it can be, for example, 0.003 mol / 100 g or more. Furthermore, the total amount of the silanol group-containing units and alkoxy group-containing units, as the total of the hydroxyl group content and alkoxy group content, in component (F) is preferably 0.008 to 0.3 mol / 100 g, more preferably 0.01 to 0.2 mol / 100 g, and particularly preferably 0.015 to 0.1 mol / 100 g. The presence of such hydroxyl groups or alkoxy groups enables condensation reactions with the hydroxyl group-containing components (A) and (B) and optional components (A') and (E).

[0088] Examples of the alkoxy group having 1 to 6 carbon atoms include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, and a phenoxy group. The silanol group-containing unit is a unit represented by R 3 2(OH)SiO 1 / 2 Units, R 3 (OH)2SiO 1 / 2 Units, R 3 (OH)SiO 2 / 2 Units: (OH)SiO 3 / 2 The alkoxy group-containing unit is, for example, R 3 2(OR')SiO 1 / 2 Units, R 3 (OR')2SiO 1 / 2 Units, R 3 (OR')SiO 2 / 2 Units: (OR')SiO 3 / 2 (OR' are each independently an alkoxy group having 1 to 6 carbon atoms, as exemplified above). 3 3SiO 1 / 2 Units, SiO 4 / 2 units, and optionally R 3 2SiO 2 / 2 In the case where the hydroxyl group or alkoxyl group is SiO 4 / 2 It can be bonded to a silicon atom from the unit.

[0089] The (F) component preferably has a weight average molecular weight of 1,000 to 10,000, more preferably 1,200 to 8,000, even more preferably 1,400 to 6,000, and even more preferably 1,600 to 4,000. If the molecular weight is below the above lower limit or exceeds the above upper limit, the adhesive strength and storage modulus G' of the resulting adhesive layer may decrease.

[0090] In the silicone pressure-sensitive adhesive composition of the present invention, the blending ratio of the above-mentioned components (A), (B), and optional components (A'), (E), and (F) is preferably 25 to 70 mass %, more preferably 30 to 60 mass %, even more preferably 33 to 55 mass %, and most preferably 35 to 50 mass %, of component (A) relative to the total mass of components (A), (B), (A'), (E), and (F). The blending ratio of component (B) is preferably 5 to 70 mass %, more preferably 6 to 55 mass %, even more preferably 8 to 50 mass %, and most preferably 10 to 45 mass %, based on the total mass of components (A), (B), (A'), (E), and (F). The blending ratio of component (A') is preferably 0 to 50 mass %, more preferably 0 to 40 mass %, and most preferably 0 to 30 mass %, relative to the total mass of components (A), (B), (A'), (E), and (F). The blending ratio of component (E) is preferably 0 to 35 mass%, more preferably 0 to 30 mass%, and even more preferably 0 to 25 mass%, based on the total mass of components (A), (B), (A'), (E), and (F). When component (E) is included, the lower limit should be 0.01 mass% or more. The blending ratio of component (F) is preferably 0 to 45 mass%, more preferably 0 to 40 mass%, even more preferably 0 to 35 mass%, and most preferably 0 to 30 mass%, based on the total mass of components (A), (B), (A'), (E), and (F). When component (F) is included, the lower limit should be 0.01 mass% or more.

[0091] The amount of each component relative to the total mass of the entire silicone pressure-sensitive adhesive composition, including optional components described below, is preferably 0.1 to 70 mass% for component (A), more preferably 0.3 to 60 mass%, and even more preferably 0.5 to 55 mass% for component (B). Component (B) is preferably 0.01 to 70 mass%, more preferably 0.05 to 55 mass%, and even more preferably 0.10 to 50 mass% for component (A'). Component (E) is preferably 0 to 35 mass%, more preferably 0 to 30 mass%, and even more preferably 0 to 25 mass% for component (E). When component (E) is included, the lower limit is preferably 0.01 mass% or greater. Component (F) is preferably 0 to 45 mass%, more preferably 0 to 40 mass%, even more preferably 0 to 35 mass%, and most preferably 0 to 30 mass%. When component (E) is contained, the lower limit should be 0.01 mass % or more.

[0092] In the silicone pressure-sensitive adhesive composition of the present invention, the ratio of the total mass of the linear organopolysiloxane component to the total mass of the organopolysiloxane resin component is 25 / 75 to 70 / 30, more preferably 30 / 70 to 60 / 40, more preferably 33 / 67 to 55 / 45, more preferably 35 / 65 to 50 / 50, and even more preferably 40 / 60 to 48 / 52. That is, the ratio of (total mass of component (A) and optional component (A')) / (total mass of component (B) and optional component (E) and / or component (F)) is 25 / 75 to 70 / 30, more preferably 30 / 70 to 60 / 40, more preferably 33 / 67 to 55 / 45, more preferably 35 / 65 to 50 / 50, and even more preferably 40 / 60 to 48 / 52. If the viscosity is less than the lower limit or more than the upper limit, the adhesive strength and storage modulus G' of the resulting adhesive layer may decrease.

[0093] Another preferred embodiment of the present invention is a silicone pressure-sensitive adhesive composition comprising a condensation reaction product of the above-mentioned component (A), the optional component (A'), the component (B), and the optional components (F) and / or (E). That is, some or all of the components (A), (B), and the optional components (A'), (E), and (F) may be subjected to a condensation reaction in advance. Specifically, the alkoxy or hydroxyl groups of component (A) and optional component (A') and the alkoxy or hydroxyl groups of component (B) and optional components (E) and (F) may be subjected to a hydrolysis-condensation or condensation reaction to obtain a condensation reaction product, which may then be mixed with the other components. Alternatively, the alkoxy or hydroxyl groups of optional component (A') and the alkoxy or hydroxyl groups of component (B) and optional components (E) and (F) may be subjected to a hydrolysis-condensation or condensation reaction to obtain a condensation reaction product, which may then be mixed with the other components. Alternatively, the alkoxy groups or hydroxyl groups of component (A) and any component (A') and the alkoxy groups or hydroxyl groups of component (B) and any component (E) and component (F) may be subjected to a hydrolysis condensation reaction or condensation reaction to obtain a condensation reaction product, which may then be mixed with the other components.

[0094] To carry out the condensation reaction, a mixture of component (A) and / or (A') dissolved in a solvent such as toluene and component (B) and / or (E) and / or (F) is reacted at room temperature (25°C) or with heat using one or more condensation catalysts, such as acids, bases, or organic acid metal salts, and neutralized as necessary. In this case, the reaction is preferably carried out so that the total amount of hydroxyl and alkoxy groups in the SiOH groups (silanol groups) in the condensation reaction product is 0.3 mol / 100 g or less, particularly 0.25 mol / 100 g or less. The lower limit is not particularly limited, and is, for example, 0.001 mol / 100 g or more. Therefore, the silicone pressure-sensitive adhesive composition of the present invention can be a composition containing the product obtained by the condensation reaction of component (A) and / or (A') with component (B) and / or (E) and / or (F), as well as the aforementioned component (C) and component (D). By carrying out a condensation reaction beforehand, the adhesive strength, storage modulus G', holding power, tack, etc. of the resulting cured product can be improved, and migration of the silicone component to the adherend can be suppressed.

[0095] Examples of the basic condensation catalyst used in the reaction include metal hydroxides such as lithium hydroxide, sodium hydroxide, potassium hydroxide, and calcium hydroxide; carbonates such as sodium carbonate and potassium carbonate; bicarbonates such as sodium bicarbonate and potassium bicarbonate; metal alkoxides such as sodium methoxide and potassium butoxide; organic metals such as butyllithium; potassium silanolate; ammonia gas, aqueous ammonia, methylamine, ethylamine, propylamine, hexylamine, butanolamine, butylamine, dimethylamine, diethylamine, diethanolamine, dipropylamine, dibutylamine, dihexylamine, ethylamylamine, imidazole, propylhexylamine, trimethylamine, triethylamine, tripropylamine, tripropanolamine, pyridine, N-methylimidazole, methylpropylhexylamine, dodecylamine phosphate, tetramethylguanidine, and nitrogen compounds and salts thereof such as diazabicyclononane. Among these, ammonia gas or aqueous ammonia is preferred.

[0096] The condensation reaction temperature can be 10 to 150° C., but is usually carried out at room temperature (25° C.) to the reflux temperature of the organic solvent. The reaction time is not particularly limited, but may be 0.5 to 20 hours, preferably 1 to 16 hours.

[0097] Furthermore, after the reaction is completed, a neutralizing agent may be added to neutralize the basic catalyst, if necessary. Examples of the neutralizing agent include acidic gases such as hydrogen chloride and carbon dioxide; organic acids such as acetic acid, octylic acid, and citric acid; and mineral acids such as hydrochloric acid, sulfuric acid, and phosphoric acid. When ammonia gas, aqueous ammonia, or a low-boiling amine compound is used as the alkaline catalyst, the neutralizing agent may be distilled off by passing an inert gas such as nitrogen through the reaction system.

[0098] [(G) component] Component (G) is an optional addition reaction inhibitor. It can be added before heat curing, for example, during preparation of the silicone pressure-sensitive adhesive composition or during application of the pressure-sensitive adhesive composition to a substrate, to prevent thickening or gelation of the treatment liquid containing the pressure-sensitive adhesive composition. Examples of such additives include various organic nitrogen compounds, organic phosphorus compounds, organic silicon compounds, acetylene compounds, unsaturated carboxylic acid esters, and oxime compounds.

[0099] More specifically, for example, acetylenic alcohols such as 3-methyl-1-butyn-3-ol, 3,5-dimethyl-1-hexyn-3-ol, 3-methyl-1-pentyn-3-ol, 2-phenyl-3-butyn-2-ol, and 1-ethynylcyclohexanol; Acetylenic compounds such as 3-methyl-3-penten-1-yne, 3,5-dimethyl-3-hexen-1-yne, 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, and chlorosilanes or alkoxysilanes. Examples of the (G) component include reaction products with silane, siloxane, or hydrogen silane, vinyl siloxanes such as 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane and 1,1,3,3-tetramethyl-1,3-divinyldisiloxane, unsaturated carboxylic acid esters such as diallyl maleate, dimethyl maleate, diallyl fumarate, and diethyl fumarate, organic nitrogen compounds such as benzotriazole, other organic phosphorus compounds, and oxime compounds. Component (G) may be used alone or in combination of two or more.

[0100] The amount of component (G) blended is in the range of 0 to 8.0 parts by mass per 100 parts by mass of the total of components (A), (B), (C), and optional components (A'), (E), and (F). When blended, the amount is preferably in the range of 0.01 to 8.0 parts by mass, and more preferably in the range of 0.05 to 5.0 parts by mass. If the blended amount exceeds the upper limit, the curability of the resulting composition may decrease. If the blended amount is equal to or greater than the lower limit, the reaction control effect is fully exerted.

[0101] [Other optional ingredients] In addition to the above components, other components can be optionally added to the silicone pressure-sensitive adhesive composition of the present invention. The amount of other components may be the same as that of conventionally known silicone pressure-sensitive adhesives, and may be appropriately adjusted within a range that does not impair the effects of the present invention. Examples of such components include non-reactive organopolysiloxanes such as polydimethylsiloxane and polydimethyldiphenylsiloxane; antioxidants such as phenols, quinones, amines, phosphorus, phosphites, sulfur, and thioethers; light stabilizers such as triazoles and benzophenones; flame retardants such as phosphate esters, halogens, phosphorus, and antimony; antistatic agents such as cationic surfactants, anionic surfactants, and nonionic surfactants; dyes; pigments; antifoaming agents; fillers; leveling agents; adhesion improvers such as silane coupling agents; thickeners; photopolymerization initiators; reactive diluents, and solvents for reducing viscosity during coating.

[0102] Examples of the solvent include aromatic hydrocarbon solvents such as toluene and xylene, aliphatic hydrocarbon solvents such as hexane, heptane, octane, isooctane, decane, cyclohexane, methylcyclohexane, and isoparaffin, hydrocarbon solvents such as industrial gasoline, petroleum benzine, and solvent naphtha, ketone solvents such as acetone, methyl ethyl ketone, 2-pentanone, 3-pentanone, 2-hexanone, 2-heptanone, 4-heptanone, methyl isobutyl ketone, diisobutyl ketone, acetonylacetone, and cyclohexanone, ester solvents such as ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, and isobutyl acetate, and diethyl ether solvents. Examples of solvents that can be used include ether solvents such as diethyl ether, dipropyl ether, diisopropyl ether, dibutyl ether, 1,2-dimethoxyethane, and 1,4-dioxane, solvents having an ester and an ether moiety such as 2-methoxyethyl acetate, 2-ethoxyethyl acetate, propylene glycol monomethyl ether acetate, and 2-butoxyethyl acetate, and siloxane solvents such as hexamethyldisiloxane, octamethyltrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, tris(trimethylsiloxy)methylsilane, and tetrakis(trimethylsiloxy)silane. These can be used alone or in appropriate combinations of two or more. When a solvent is added, the amount thereof is preferably 10 to 20,000 parts by mass, more preferably 25 to 10,000 parts by mass, and particularly preferably 50 to 1,000 parts by mass, per 100 parts by mass of the total of components (A), (B), and (C), and optional components (A'), (E), and (F). The silicone pressure-sensitive adhesive composition of the present invention can also be a solvent-free type.

[0103] [Method of manufacturing silicone pressure-sensitive adhesive composition] (I) A silicone pressure-sensitive adhesive composition containing a linear organopolysiloxane and the organopolysiloxane resin can be prepared by mixing and dissolving the above-mentioned components. From the standpoint of pot life, it is desirable to first uniformly mix components (A), (B), and (C), optional components (A'), (E), and (F), optionally component (G), and other optional components, and then add component (D) immediately before use. (II) A silicone pressure-sensitive adhesive composition containing a condensation reaction product of at least one linear organopolysiloxane with at least one other linear organopolysiloxane can be produced by, as described above, previously condensing component (A) and / or optional component (A') and component (B) and / or optional component (E), and / or optional component (F).

[0104] The silicone pressure-sensitive adhesive composition of the present invention can be applied to various substrates and cured under specified conditions to obtain a silicone adhesive layer. The silicone pressure-sensitive adhesive composition of the present invention can be suitably used, for example, as an adhesive tape, adhesive sheet, or adhesive film having a substrate and an adhesive layer made of a cured product of the composition laminated on at least one side of the substrate.

[0105] [Base material] Examples of the substrate include paper, plastic film, glass, metal, and cloth. Examples of paper include fine paper, coated paper, art paper, glassine paper, polyethylene-laminated paper, kraft paper, Japanese paper, and synthetic paper. Examples of plastic films include polyethylene film, polypropylene film, polyester film, polyimide film, polyamide film, polyvinyl chloride film, polyvinylidene chloride film, polyvinyl alcohol film, polycarbonate film, polytetrafluoroethylene film, polystyrene film, ethylene-vinyl acetate copolymer film, ethylene-vinyl alcohol copolymer film, triacetyl cellulose film, polyether ether ketone film, and polyphenylene sulfide film. There are no particular limitations on the thickness or type of glass, and it may be chemically strengthened. Glass fiber can also be used, and it may be used alone or in combination with other resins. Examples of cloth include natural fiber cloth, synthetic fiber cloth, and artificial leather. Examples of metals include aluminum foil, copper foil, gold foil, silver foil, and nickel foil.

[0106] To further improve the adhesion between these substrates and the silicone adhesive layer, the substrate may be subjected to a primer treatment, corona treatment, etching treatment, sandblasting treatment, or plasma treatment.

[0107] The surface of the substrate opposite to the adhesive layer surface may be surface-treated to prevent scratches, stains, fingerprints, glare, reflection, static electricity, etc. The adhesive layer may be applied to the substrate before the surface treatment, or the adhesive layer may be applied after the surface treatment.

[0108] Examples of the scratch prevention treatment (hard coating treatment) include treatment with an acrylate-based, silicone-based, oxetane-based, inorganic-based, or organic-inorganic hybrid hard coating agent.

[0109] Examples of the antifouling treatment include treatment with an antifouling agent such as a fluorine-based, silicone-based, ceramic-based, or photocatalytic-based agent.

[0110] Examples of antireflection treatments include wet treatments using a fluorine-based, silicone-based, or other antireflection agent, and dry treatments using vapor deposition or sputtering. Examples of antistatic treatments include treatments using surfactant-based, silicone-based, organoboron-based, conductive polymer-based, metal oxide-based, or vapor-deposited metal-based antistatic agents.

[0111] [Method for manufacturing adhesive tape and adhesive film] The coating method may be any known coating method, such as a comma coater, lip coater, roll coater, die coater, knife coater, blade coater, rod coater, bar coater, kiss coater, gravure coater, screen coating, dip coating, or cast coating.

[0112] The coating amount is set appropriately depending on the application, but typically it is an amount that results in a silicone adhesive layer having a thickness of 1 to 2,000 μm, preferably 2 to 1,000 μm, and particularly 3 to 500 μm after curing.

[0113] The curing conditions for the silicone pressure-sensitive adhesive composition may be, but are not limited to, 70 to 250°C for 10 seconds to 10 minutes.

[0114] The pressure-sensitive adhesive tape or pressure-sensitive adhesive film of the present invention may be produced by directly applying the silicone pressure-sensitive adhesive composition of the present invention to a substrate as described above and curing the composition to form a silicone adhesive layer, or by a transfer method in which the composition is applied to a release-coated release film or release paper and cured to form a silicone adhesive layer, and then the silicone adhesive layer is laminated to the above-mentioned substrate.

[0115] [Adhesion and adhesive strength range] The silicone pressure-sensitive adhesive composition of the present invention is characterized by the fact that the cured layer obtained by curing the composition via a hydrosilylation reaction is adhesive. The pressure-sensitive adhesive layer of the present invention has the above-mentioned configuration and exhibits adhesive strength sufficient for practical use, so that it can be used as a substitute for known silicone pressure-sensitive adhesives, as desired.

[0116] More specifically, an adhesive tape having a 40 μm thick adhesive layer obtained by curing the silicone adhesive composition of the present invention laminated to a 25 μm thick polyimide film can be designed to have an adhesive strength of 3.0 N / 25 mm or more when measured at a tensile speed of 300 mm / min using a 180° peel test method against a 2 mm thick silicone rubber sheet (cured KE951U manufactured by Shin-Etsu Chemical Co., Ltd.) More preferably, the adhesive strength is in the range of 3.5 to 15.0 N / 25 mm, more preferably 4.0 to 13.0 N / 25 mm, even more preferably 4.5 to 12.0 N / 25 mm, and even more preferably 5.0 to 10.0 N / 25 mm. It should be noted that the thickness of the cured layer (40 μm) mentioned above is the thickness of the cured layer itself, which serves as a standard for objectively defining the adhesive strength of the cured layer according to the present invention, and it goes without saying that the silicone pressure-sensitive adhesive composition of the present invention can be used as a cured layer or adhesive layer of any thickness, not limited to 40 μm.

[0117] [Storage modulus and other viscoelastic properties] The adhesive layer obtained by curing the silicone pressure-sensitive adhesive composition of the present invention has a storage modulus G' at 25°C of 1.00 MPa or more, preferably 1.20 to 20.0 MPa, more preferably 1.50 to 18.0 MPa, even more preferably 2.00 to 15.0 MPa, even more preferably 2.50 to 13.0 MPa, and even more preferably 3.00 to 10.0 MPa. Furthermore, the storage modulus G' at 80°C of the adhesive layer obtained by curing the silicone adhesive composition of the present invention is 0.10 MPa or more, preferably 0.12 to 10.0 MPa, more preferably 0.15 to 8.00 MPa, even more preferably 0.17 to 6.00 MPa, even more preferably 0.19 to 4.0 MPa, and even more preferably 0.20 to 2.0 MPa. Because the silicone pressure-sensitive adhesive composition of the present invention has such a storage modulus G' at room temperature and at high temperatures, it is suitable for use in the formation of elastic pressure-sensitive adhesive members, as components for electronic devices and electrical equipment such as speakers and transducers, as well as for application in the fields of advanced electronic materials and display elements for smart devices and the like.

[0118] The storage modulus (G') of the pressure-sensitive adhesive layer according to the present invention can be measured by a known measurement method, for example, using a viscoelasticity measuring device DHR-2 (TA Instruments Inc.) using a disk-shaped sample having a diameter of 8 mm and a thickness of about 0.5 to 1.5 mm, with Φ8 mm parallel plates, a frequency of 1 Hz, a strain of 0.1%, a heating rate of 3°C / min, and values ​​at 25°C and 80°C in the operating temperature range of -55°C to 100°C.

[0119] [Uses of adhesive tape and adhesive film] There are no particular limitations on the types of adherends that can be bonded or fixed with a pressure-sensitive adhesive tape produced using the silicone pressure-sensitive adhesive composition of the present invention, but examples include silicone materials such as silicone rubber, silicone sealant, silicone potting material, silicone LIM material, and silicone varnish; silicone-coated release paper or film; metal, plastic, wood, cloth, or paper coated with a silicone coating material, silicone release agent, silicone water repellent, or silicone-containing paint; and composites formed by combining two or more of these. Thus, the silicone pressure-sensitive adhesive composition of the present invention can be suitably used for adhesion and bonding of silicone materials, particularly for adhesion and bonding of silicone rubber.

[0120] Furthermore, the cured product obtained by curing the silicone pressure-sensitive adhesive composition of the present invention is useful as an elastic pressure-sensitive adhesive member for various electronic devices or electrical equipment, and is particularly useful as an electronic material, a member for a display device, or a member for a transducer (including for sensors, speakers, actuators, and generators).

[0121] Furthermore, the tape is also useful for applications in high-temperature environments. Examples include heat-resistant tape, electrical insulating tape, heat-sealing tape, plating masking tape, and heat treatment masking tape. Applications include, for example, protection of adherends, masking, temporary fixation, fixation during transport, and splicing in the manufacturing process of electronic components and semiconductor components. Examples of adherends include, but are not limited to, metals such as stainless steel, copper, and iron, and these metals whose surfaces have been plated or rust-proofed; glass, tempered or stain-proofed glass, ceramics such as porcelain; resins such as polytetrafluoroethylene, polyimide, epoxy resin, novolac resin, and polarizing plates; and composites formed by combining two or more of these materials. [Example]

[0122] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to the following examples. In the following, parts represent parts by mass, and characteristic values ​​represent values ​​measured by the following test methods.

[0123] [viscosity] The viscosity (mPa·s) is a value measured using a B-type rotational viscometer in accordance with JIS K7117-1.

[0124] [Weight average molecular weight (Mw)] In the present invention, the weight average molecular weight (Mw) is a value determined by GPC (gel permeation chromatography) analysis using polystyrene as a standard substance under the following conditions. (Measurement conditions) GPC measuring device: HLC-8320 (Tosoh Corporation) Detector: Refractive index detector (RI) Measurement solvent: toluene Flow rate: 0.35mL / min GPC columns: (passed in the following order) TSKgel Guardcolumn SuperHZ-L(4.6mmI.D.×2cm×1) TSKgel SuperHZ4000(4.6mmI.D.×15cm×1) TSKgel SuperHZ3000(4.6mmI.D.×15cm×1) TSKgel SuperHZ2000 (4.6mm I.D. x 15cm x 2) (both manufactured by Tosoh Corporation) Measurement temperature: 40℃ Sample injection volume: 10 μL (toluene solution with a silicone concentration of 0.5 wt%)

[0125] [Adhesion to silicone rubber] Each silicone pressure-sensitive adhesive composition was applied to a 25 μm thick, 25 mm wide polyimide film using an applicator so that the adhesive layer after curing would be 40 μm thick, and then heated and cured at 150 ° C for 3 minutes to produce a pressure-sensitive adhesive tape. This pressure-sensitive adhesive tape was attached to a 2 mm thick silicone rubber sheet (cured KE951U (trade name) manufactured by Shin-Etsu Chemical Co., Ltd.) and pressed by moving a 2 kg rubber-coated roller back and forth once. After leaving it at room temperature for about 24 hours, one end of the pressure-sensitive adhesive tape was peeled off at 25 ° C., and the force (N / 25 mm) required to peel it from the silicone rubber sheet at a pulling rate of 300 mm / min and an angle of 180 ° was measured using a tensile tester (Shimadzu Corporation DSC-500 model tester).

[0126] [Dynamic viscoelasticity (storage modulus G')] Each silicone pressure-sensitive adhesive composition was coated onto a release liner coated with a fluorosilicone release coating to a thickness of approximately 40 μm after curing, and cured at 150°C for 3 minutes. The process of overlapping adhesive layers and peeling off the release liners was repeated to overlap 16 adhesive layers, obtaining a film sample with a thickness of 600 μm or more and sandwiched between release liners on both sides. After storing the film at 70°C for 7 days, an 8 mm diameter circle was cut out, the release liners on both sides were peeled off, and the film was attached to the parallel plate probe of a dynamic viscoelasticity apparatus to measure the storage modulus G'. (Measurement conditions) Measuring instrument: DHR-2 (TA Instruments Inc.) Adhesive jig (geometry): Φ8mm parallel plate Measurement temperature: -55℃~100℃ Heating rate: 3°C / min Frequency: 1Hz Distortion: 0.1%

[0127] The following raw materials were used in the examples and comparative examples. In the following formulas, Me represents a methyl group, Vi represents a vinyl group, and Ph represents a phenyl group. The bonding order of each siloxane unit shown in parentheses is not limited to the following. In each formula below, the total number of siloxane repeating units is an average value.

[0128] (A-1) An organopolysiloxane represented by the following formula, which has a viscosity of 58,000 mPa·s at 25°C when dissolved in toluene to a concentration of 30% by mass and contains 0.0008 mol / 100 g of alkenyl groups. [ka] (z51 and z52 are numbers that satisfy the above viscosity and vinyl group content, and the ratio of the number of hydroxyl groups to the total number of groups bonded to silicon atoms is 0.007%).

[0129] (A-2) An organopolysiloxane represented by the following formula, which has a viscosity of 25,000 mPa s at 25°C when dissolved in toluene to a concentration of 30% by mass, has an alkenyl group content of 0.0015 mol / 100 g, and has a ratio of the total number of phenyl groups to the total number of groups bonded to silicon atoms of 1.0%: [ka] (z53, z54, and z55 are numbers that satisfy the above viscosity, vinyl group content, and phenyl group content, and the ratio of the number of hydroxyl groups to the total number of groups bonded to silicon atoms is 0.006%).

[0130] (A'-1) An organopolysiloxane represented by the following formula, in which both molecular chain terminals are capped with SiOH groups and which contains no alkenyl groups, has a viscosity of 70,000 mPa·s at 25°C when dissolved in toluene to a concentration of 30% by mass. [ka] (z58 is the number that satisfies the above viscosity, and the ratio of the number of hydroxyl groups to the total number of groups bonded to silicon atoms is 0.017%)

[0131] (B-1) Me3SiO 1 / 2 Units and SiO 4 / 2 Organopolysiloxane (MeSiO 1 / 2 Units / SiO 4 / 2 Unit (molar ratio) = 0.70 / 1.0, weight average molecular weight 7,120, silicon atom-bonded hydroxyl group content 0.026 mol / 100 g, hydroxyl group is SiO 4 / 2 (bonded to silicon atoms derived from units)

[0132] (B-2) Me3SiO 1 / 2 Units and SiO 4 / 2 Organopolysiloxane (MeSiO 1 / 2 Units / SiO 4 / 2 Unit (molar ratio) = 0.68 / 1.0, weight average molecular weight 6,910, silicon atom-bonded hydroxyl group content 0.033 mol / 100 g, hydroxyl group is SiO 4 / 2 (bonded to silicon atoms derived from units)

[0133] (B-3) Me3SiO 1 / 2 Units and SiO 4 / 2 Organopolysiloxane (MeSiO 1 / 2 Units / SiO 4 / 2Unit (molar ratio) = 0.72 / 1.0, weight average molecular weight 9,010, silicon atom-bonded hydroxyl group content 0.031 mol / 100 g, hydroxyl group is SiO 4 / 2 (bonded to silicon atoms derived from units)

[0134] (C-1) Organohydrogenpolysiloxane represented by the following formula: [ka] Ratio of SiH groups: 46.5%, Amount of hydrogen atoms bonded to silicon atoms: 1.558 mol / 100 g

[0135] (C-2) Organohydrogenpolysiloxane represented by the following formula: [ka] Ratio of SiH groups: 41.7%, Amount of hydrogen atoms bonded to silicon atoms: 1.409 mol / 100 g

[0136] (D-1) Platinum catalyst: CAT-PL-50T (Shin-Etsu Chemical Co., Ltd.)

[0137] (E-1) Me3SiO 1 / 2 Units and SiO 4 / 2 Organopolysiloxane (MeSiO 1 / 2 Units / SiO 4 / 2 Unit (molar ratio) = 0.83 / 1.0, weight average molecular weight 3,450, silicon atom-bonded hydroxyl group content 0.078 mol / 100 g, hydroxyl group is SiO 4 / 2 (bonded to silicon atoms derived from units)

[0138] (E-2) Me3SiO 1 / 2 Units and SiO 4 / 2 Organopolysiloxane (MeSiO 1 / 2 Units / SiO 4 / 2Unit (molar ratio) = 0.84 / 1.0, weight average molecular weight 2,190, silicon atom-bonded hydroxyl group content 0.108 mol / 100 g, hydroxyl group is SiO 4 / 2 (bonded to silicon atoms derived from units)

[0139] (E-3) Me3SiO 1 / 2 Units and SiO 4 / 2 Organopolysiloxane (MeSiO 1 / 2 Units / SiO 4 / 2 Unit (molar ratio) = 0.68 / 1.0, weight average molecular weight 2,690, silicon atom-bonded hydroxyl group content 0.110 mol / 100 g, hydroxyl group is SiO 4 / 2 (bonded to silicon atoms derived from units)

[0140] (E-4) Me3SiO 1 / 2 Units and SiO 4 / 2 Organopolysiloxane (MeSiO 1 / 2 Units / SiO 4 / 2 Unit (molar ratio) = 0.76 / 1.0, weight average molecular weight 4,320, silicon atom-bonded hydroxyl group content 0.051 mol / 100 g, hydroxyl group is SiO 4 / 2 (bonded to silicon atoms derived from units)

[0141] (F-1) Me3SiO 1 / 2 Units, MeViSiO 2 / 2 units, and SiO 4 / 2 Organopolysiloxane (MeSiO 1 / 2 Units / MeViSiO 2 / 2 Units / SiO 4 / 2 Unit (molar ratio) = 0.79 / 0.13 / 1.0, weight average molecular weight 2,380, alkenyl group content 0.123 mol / 100 g, silicon atom-bonded hydroxyl group content 0.031 mol / 100 g, hydroxyl group is SiO 4 / 2 (bonded to silicon atoms derived from units)

[0142] (F-2) Me3SiO 1 / 2 Units, Me2ViSiO 1 / 2 units, and SiO 4 / 2 Organopolysiloxane (MeSiO 1 / 2 Units / Me2ViSiO 1 / 2 / SiO 4 / 2 Unit (molar ratio) = 0.73 / 0.12 / 1.0, weight average molecular weight 2,950, alkenyl group content 0.089 mol / 100 g, silicon atom-bonded hydroxyl group content 0.026 mol / 100 g, hydroxyl group is SiO 4 / 2 (bonded to silicon atoms derived from units)

[0143] (G-1) Ethynylcyclohexanol

[0144] [Comparative Additives] (H-1) Organic peroxide curing agent: benzoyl peroxide (trade name: Nyper (registered trademark) BMT-K40, manufactured by NOF Corporation)

[0145] [Preparation of Silicone Pressure-Sensitive Adhesive Base Composition] <Preparation Example 1> The linear organopolysiloxane (A-1) (43 parts by mass), a 50% by mass toluene solution of the organopolysiloxane resin (B-1) (114 parts by mass), and the ethynylcyclohexanol (G-1) (0.2 parts by mass) were mixed, and toluene (71.5 parts by mass) was added to obtain a silicone pressure-sensitive adhesive base composition (1) containing approximately 50% by mass of the active ingredient.

[0146] <Preparation Example 2> The linear organopolysiloxane (A-1) (40 parts by mass), a 50% by mass toluene solution of the organopolysiloxane resin (B-2) (100 parts by mass), a 50% by mass toluene solution of the organopolysiloxane resin (E-1) (20 parts by mass), and the ethynylcyclohexanol (G-1) (0.2 parts by mass) were mixed, and toluene (70 parts by mass) was added to obtain a silicone pressure-sensitive adhesive base composition (2) containing approximately 50% by mass of the active ingredient.

[0147] <Preparation Example 3> The linear organopolysiloxane (A-1) (40 parts by mass), a 50% by mass toluene solution of the organopolysiloxane resin (B-1) (90 parts by mass), a 50% by mass toluene solution of the organopolysiloxane resin (F-1) (30 parts by mass), and the ethynylcyclohexanol (G-1) (0.2 parts by mass) were mixed, and toluene (70 parts by mass) was added to obtain a silicone pressure-sensitive adhesive base composition (3) containing approximately 50% by mass of the active ingredient.

[0148] <Preparation Example 4> A solution consisting of the linear organopolysiloxane (A-1) (41 parts by mass), a 50% by mass toluene solution of the organopolysiloxane resin (B-1) (118 parts by mass), toluene (70.5 parts by mass), and aqueous ammonia (0.5 parts by mass) was stirred at room temperature (25°C) for 12 hours to allow a condensation reaction. The mixture was then heated under reflux at approximately 110-125°C for 6 hours to distill off the ammonia and water. The resulting reaction product was allowed to cool, and then the ethynylcyclohexanol (G-1) (0.2 parts by mass) was added thereto. Toluene was added and mixed to adjust the solids content to approximately 50% by mass, yielding a silicone pressure-sensitive adhesive base composition (4).

[0149] <Preparation Example 5> A solution consisting of the linear organopolysiloxane (A-1) (43 parts by mass), a 50% by mass toluene solution of the organopolysiloxane resin (B-1) (84 parts by mass), toluene (71.5 parts by mass), and aqueous ammonia (0.5 parts by mass) was stirred at room temperature (25°C) for 12 hours to allow a condensation reaction. The mixture was then heated under reflux at approximately 110-125°C for 6 hours to distill off the ammonia and water. The resulting reaction product was allowed to cool, and then a 50% by mass toluene solution of the organopolysiloxane resin (F-1) (30 parts by mass) and the ethynylcyclohexanol (G-1) (0.2 parts by mass) were added to the mixture, followed by addition of toluene to adjust the solids content to approximately 50% by mass, yielding a silicone pressure-sensitive adhesive base composition (5).

[0150] <Preparation Example 6> A solution consisting of the linear organopolysiloxane (A-1) (42 parts by mass), a 50% by mass toluene solution of the organopolysiloxane resin (B-1) (68 parts by mass), a 50% by mass toluene solution of the organopolysiloxane resin (F-1) (48 parts by mass), toluene (71 parts by mass), and aqueous ammonia (0.5 parts by mass) was stirred at room temperature (25°C) for 12 hours to cause a condensation reaction. The solution was then heated under reflux at approximately 110 to 125°C for 6 hours to distill off the ammonia and water. The resulting reaction product was allowed to cool, and then the ethynylcyclohexanol (G-1) (0.2 parts by mass) was added to it, and toluene was added and mixed to adjust the solids content to approximately 50% by mass, yielding a silicone pressure-sensitive adhesive base composition (6).

[0151] <Preparation Example 7> A solution consisting of the linear organopolysiloxane (A-1) (40 parts by mass), a 50% by mass toluene solution (80 parts by mass) of the organopolysiloxane resin (B-2), a 50% by mass toluene solution (40 parts by mass) of the organopolysiloxane resin (F-1), toluene (70 parts by mass), and aqueous ammonia (0.5 parts by mass) was stirred at room temperature (25°C) for 12 hours to allow a condensation reaction. The mixture was then heated under reflux at approximately 110 to 125°C for 6 hours to distill off the ammonia and water. The resulting reaction product was allowed to cool, and then the ethynylcyclohexanol (G-1) (0.2 parts by mass) was added thereto, followed by addition of toluene to adjust the solids content to approximately 50% by mass, yielding a silicone pressure-sensitive adhesive base composition (7).

[0152] <Preparation Example 8> A solution consisting of the linear organopolysiloxane (A-1) (45 parts by mass), a 50% by mass toluene solution (70 parts by mass) of the organopolysiloxane resin (B-2), a 50% by mass toluene solution (40 parts by mass) of the organopolysiloxane resin (F-2), toluene (72.5 parts by mass), and aqueous ammonia (0.5 parts by mass) was stirred at room temperature (25°C) for 12 hours to cause a condensation reaction. The solution was then heated under reflux at approximately 110 to 125°C for 6 hours to distill off the ammonia and water. The resulting reaction product was allowed to cool, and then the ethynylcyclohexanol (G-1) (0.2 parts by mass) was added to it, and toluene was added and mixed to adjust the solids content to approximately 50% by mass, yielding a silicone pressure-sensitive adhesive base composition (8).

[0153] <Preparation Example 9> A solution consisting of the linear organopolysiloxane (A-1) (38 parts by mass), a 50% by mass toluene solution of the organopolysiloxane resin (B-3) (20 parts by mass), a 50% by mass toluene solution of the organopolysiloxane resin (E-3) (44 parts by mass), a 50% by mass toluene solution of the organopolysiloxane resin (F-1) (60 parts by mass), toluene (69 parts by mass), and aqueous ammonia (0.5 parts by mass) was stirred at room temperature (25°C) for 12 hours to allow a condensation reaction. The solution was then heated under reflux at approximately 110 to 125°C for 6 hours, and the ammonia and water were distilled off. The resulting reaction product was allowed to cool, and then the ethynylcyclohexanol (G-1) (0.2 parts by mass) was added to it, and toluene was added and mixed to adjust the solids content to approximately 50% by mass, yielding a silicone pressure-sensitive adhesive base composition (9).

[0154] <Preparation Example 10> A solution consisting of the linear organopolysiloxane (A-2) (42 parts by mass), a 50% by mass toluene solution of the organopolysiloxane resin (B-2) (76 parts by mass), a 50% by mass toluene solution of the organopolysiloxane resin (F-1) (40 parts by mass), toluene (71 parts by mass), and aqueous ammonia (0.5 parts by mass) was stirred at room temperature (25°C) for 12 hours to allow a condensation reaction. The mixture was then heated under reflux at approximately 110-125°C for 6 hours to distill off the ammonia and water. The resulting reaction product was allowed to cool, and then the ethynylcyclohexanol (G-1) (0.2 parts by mass) was added thereto. Toluene was added and mixed to adjust the solids content to approximately 50% by mass, yielding a silicone pressure-sensitive adhesive base composition (10).

[0155] <Preparation Example 11> A solution consisting of the linear organopolysiloxane (A-1) (35 parts by mass), the linear organopolysiloxane (A'-1) (5 parts by mass), a 50% by mass toluene solution of the organopolysiloxane resin (B-2) (70 parts by mass), a 50% by mass toluene solution of the organopolysiloxane resin (E-3) (10 parts by mass), a 50% by mass toluene solution of the organopolysiloxane resin (F-1) (40 parts by mass), toluene (70 parts by mass), and aqueous ammonia (0.5 parts by mass) was stirred at room temperature (25°C) for 12 hours to cause a condensation reaction. The solution was then heated under reflux at about 110 to 125°C for 6 hours, and the ammonia and water were distilled off. After allowing the resulting reaction product to cool, the above (G-1) ethynylcyclohexanol (0.2 parts by mass) was added to it, and toluene was added and mixed so that the solid content was approximately 50% by mass, yielding a silicone adhesive base composition (11).

[0156] <Preparation Example 12> The linear organopolysiloxane (A-1) (37 parts by mass), a 50% by mass toluene solution of the organopolysiloxane resin (E-1) (126 parts by mass), and the ethynylcyclohexanol (G-1) (0.2 parts by mass) were mixed, and toluene (68.5 parts by mass) was added to obtain a silicone pressure-sensitive adhesive base composition (12) containing approximately 50% by mass of the active ingredient.

[0157] <Preparation Example 13> The linear organopolysiloxane (A-1) (43 parts by mass), a 50% by mass toluene solution of the organopolysiloxane resin (E-4) (114 parts by mass), and the ethynylcyclohexanol (G-1) (0.2 parts by mass) were mixed, and toluene (71.5 parts by mass) was added to obtain a silicone pressure-sensitive adhesive base composition (13) containing approximately 50% by mass of the active ingredient.

[0158] <Preparation Example 14> A solution consisting of the linear organopolysiloxane (A-1) (40 parts by mass), a 50% by mass toluene solution of the organopolysiloxane resin (E-2) (120 parts by mass), toluene (70 parts by mass), and aqueous ammonia (0.5 parts by mass) was stirred at room temperature (25°C) for 12 hours to cause a condensation reaction. The mixture was then heated under reflux at approximately 110-125°C for 6 hours to distill off the ammonia and water. The resulting reaction product was allowed to cool, and then the ethynylcyclohexanol (G-1) (0.2 parts by mass) was added thereto, followed by addition of toluene to adjust the solids content to approximately 50% by mass, yielding a silicone pressure-sensitive adhesive base composition (14).

[0159] <Preparation Example 15> A solution consisting of the linear organopolysiloxane (A-1) (45 parts by mass), a 50% by mass toluene solution of the organopolysiloxane resin (E-3) (110 parts by mass), toluene (72.5 parts by mass), and aqueous ammonia (0.5 parts by mass) was stirred at room temperature (25°C) for 12 hours to cause a condensation reaction. The mixture was then heated under reflux at approximately 110-125°C for 6 hours to distill off the ammonia and water. The resulting reaction product was allowed to cool, and then the ethynylcyclohexanol (G-1) (0.2 parts by mass) was added thereto. Toluene was added and mixed to adjust the solids content to approximately 50% by mass, yielding a silicone pressure-sensitive adhesive base composition (15).

[0160] <Preparation Example 16> A solution consisting of the linear organopolysiloxane (A-1) (42 parts by mass), a 50% by mass toluene solution of the organopolysiloxane resin (F-1) (116 parts by mass), toluene (71 parts by mass), and aqueous ammonia (0.5 parts by mass) was stirred at room temperature (25°C) for 12 hours to cause a condensation reaction. The mixture was then heated under reflux at approximately 110-125°C for 6 hours to distill off the ammonia and water. The resulting reaction product was allowed to cool, and then (G-1) ethynylcyclohexanol (0.2 parts by mass) was added thereto, followed by addition of toluene and mixing to adjust the solids content to approximately 50% by mass, yielding a silicone pressure-sensitive adhesive base composition (16).

[0161] <Preparation Example 17> A solution consisting of the linear organopolysiloxane (A-1) (45 parts by mass), a 50% by mass toluene solution (70 parts by mass) of the organopolysiloxane resin (E-2), a 50% by mass toluene solution (40 parts by mass) of the organopolysiloxane resin (F-1), toluene (72.5 parts by mass), and aqueous ammonia (0.5 parts by mass) was stirred at room temperature (25°C) for 12 hours to allow a condensation reaction. The solution was then heated under reflux at approximately 110 to 125°C for 6 hours to distill off the ammonia and water. The resulting reaction product was allowed to cool, and then the ethynylcyclohexanol (G-1) (0.2 parts by mass) was added thereto, followed by addition of toluene to adjust the solids content to approximately 50% by mass, yielding a silicone pressure-sensitive adhesive base composition (17).

[0162] <Preparation Example 18> A solution consisting of the linear organopolysiloxane (A'-1) (45 parts by mass), a 50% by mass toluene solution of the organopolysiloxane resin (E-3) (110 parts by mass), toluene (72.5 parts by mass), and aqueous ammonia (0.5 parts by mass) was stirred at room temperature (25°C) for 12 hours to cause a condensation reaction. The solution was then heated under reflux at approximately 110 to 125°C for 6 hours to distill off the ammonia and water. The resulting reaction product was allowed to cool, and then toluene was added and mixed to adjust the solids content to approximately 50% by mass, yielding a silicone pressure-sensitive adhesive base composition (18).

[0163] [Preparation and Characterization of Silicone Pressure-Sensitive Adhesive Compositions] <Examples 1 to 11 and Comparative Examples 1 to 8> The above-described silicone pressure-sensitive adhesive base composition and the above-described (C) organohydrogenpolysiloxane were placed in a flask according to the blending amounts shown in Tables 1 to 4, and 50 parts by mass of toluene was added and stirred to dissolve. The above-described (D-1) platinum catalyst was added to the resulting solution in an amount equivalent to 50 ppm of platinum by mass relative to the total mass of components (A), (A'), (B), (C), (E), and (F), and the mixture was stirred and mixed to prepare a silicone pressure-sensitive adhesive composition. The resulting silicone pressure-sensitive adhesive composition was cured using the method described above. The adhesive strength to silicone rubber and dynamic viscoelasticity (storage modulus G') were measured using the methods described above, and the evaluation results are shown in Tables 1 to 4.

[0164] <Comparative Example 9> The silicone pressure-sensitive adhesive base composition (18) shown above was placed in a flask according to the blending amounts in Table 4, and 50 parts by mass of toluene was added and stirred to dissolve. 3.0 parts by mass of the organic peroxide curing agent (H-1) above was added to the resulting solution, and the mixture was stirred to prepare a silicone pressure-sensitive adhesive composition. The resulting silicone pressure-sensitive adhesive composition was cured using the method described above. The adhesive strength to silicone rubber and dynamic viscoelasticity (storage modulus G') were measured using the methods described above, and the evaluation results are shown in Table 4.

[0165] [Table 1]

[0166] [Table 2]

[0167] [Table 3]

[0168] [Table 4]

[0169] As shown in Tables 3 and 4 above, the silicone rubber compositions of Comparative Examples 1 to 4 and 6, which used component (E) with a weight-average molecular weight of less than 5000 instead of component (B), exhibited low adhesion to silicone rubber and low storage modulus G' at both room temperature and 80° C. Furthermore, the silicone rubber composition of Comparative Example 5, in which the SiH / Vi number ratio was set to 300, exhibited improved adhesion to silicone rubber, but only a slight improvement in storage modulus G'. Furthermore, the silicone rubber composition of Comparative Example 7, which used (F) having an alkenyl group instead of component (B), and the silicone rubber composition of Comparative Example 8, which did not contain component (B) but contained components (E) and (F), also had low adhesive strength and storage modulus G' of the silicone rubber. Furthermore, the silicone rubber composition of Comparative Example 9, which used benzoyl peroxide as the organic peroxide curing agent, had high adhesive strength to silicone rubber but a low storage modulus G'.

[0170] In contrast, as shown in Tables 1 and 2, pressure-sensitive adhesive tapes made from the silicone pressure-sensitive adhesive composition of the present invention exhibited high adhesive strength to silicone rubber and also had high storage moduli G' at 25°C and 80°C. This is thought to be because the organopolysiloxane resin component (B) having a weight-average molecular weight of 5,000 or greater maintains its crystallinity even in high-temperature environments. [Industrial Applicability]

[0171] As described above, a pressure-sensitive adhesive tape or film having an adhesive layer formed by curing the silicone pressure-sensitive adhesive composition of the present invention has strong adhesive strength to silicone rubber and can maintain a high storage modulus G' even at high temperatures. Therefore, the silicone pressure-sensitive adhesive composition of the present invention is useful for pressure-sensitive adhesive tapes or films for adhering and bonding silicone materials, masking tapes, temporary fixing tapes, heat-sealing tapes in the manufacturing processes of electronic components and semiconductor components, and components for electronic materials or display devices.

Claims

1. (I) at least one linear organopolysiloxane and R ３ ３ SiO １／２ Units and SiO ４／２ or (II) at least one linear organopolysiloxane and at least one organopolysiloxane resin having a unit R ３ ３ SiO １／２ Units and SiO ４／２ A silicone pressure-sensitive adhesive composition comprising a condensation reaction product of at least one organopolysiloxane resin having a hydroxyl group unit, The linear organopolysiloxane in (I) and (II) is (A) a linear organopolysiloxane having one or more alkenyl groups per molecule, an alkenyl group content of 0.0001 to 0.03 mol / 100 g, and optionally having a hydroxyl group or an alkoxy group having 1 to 6 carbon atoms bonded to a silicon atom, and (A') optionally containing a linear organopolysiloxane having no alkenyl groups and no hydrogen atoms bonded to a silicon atom, The organopolysiloxane resin in (I) and (II) is (B) R ３ ３ SiO １／２ Units and SiO ４／２ units, and has a hydroxyl group and / or an alkoxy group having 1 to 6 carbon atoms bonded to a silicon atom, (R ３ ３ SiO １／２ Unit) / (SiO ４／２ The organopolysiloxane resin (wherein R ３ and each independently represent a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, a hydroxyl group, or an alkoxy group having 1 to 6 carbon atoms, wherein the organopolysiloxane resin does not contain any alkenyl groups or contains alkenyl groups in an amount such that the total amount of alkenyl groups in the organopolysiloxane resin is less than 0.005 mol / 100 g, and the organopolysiloxane resin has a weight average molecular weight of 5,000 or more as measured by gel permeation chromatography relative to standard polystyrene; The silicone pressure-sensitive adhesive composition further comprises: (C) Organohydrogenpolysiloxane having three or more hydrogen atoms bonded to silicon atoms in each molecule an amount such that the ratio of the total number of SiH groups in component (C) to the total number of alkenyl groups in the alkenyl group-containing organopolysiloxane contained in the silicone pressure-sensitive adhesive composition is 0.1 to 30.0; and (D) a catalytic amount of a platinum group metal catalyst; the silicone pressure-sensitive adhesive composition, wherein the ratio of the total mass of the linear organopolysiloxane to the total mass of the organopolysiloxane resin is 25 / 75 to 70 / 30;

2. 2. The silicone pressure-sensitive adhesive composition according to claim 1, wherein, relative to the total mass of the silicone pressure-sensitive adhesive composition, the amount of component (A) is 0.1 to 70 mass%, the amount of component (B) is 0.01 to 70 mass%, and the amount of component (A') is 0 to 50 mass%.

3. (F)R ３ ３ SiO １／２ Units and SiO ４／２ units, (R ３ ３ SiO １／２ Unit) / (SiO ４／２ units) is 0.5 to 1.5, has one or more alkenyl groups in one molecule, the alkenyl group content is 0.005 to 0.5 mol / 100 g, and optionally has silicon-bonded hydroxyl groups and / or silicon-bonded alkoxy groups having 1 to 6 carbon atoms (wherein R ３ and each independently represent a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, a hydroxyl group, or an alkoxy group having 1 to 6 carbon atoms) in an amount of 0.01 to 45 mass % relative to the total mass of the silicone pressure-sensitive adhesive composition.

4. 4. The silicone pressure-sensitive adhesive composition according to claim 3, comprising a condensation reaction product of said component (A), optionally said component (A'), said component (B), and said component (F).

5. 4. The silicone pressure-sensitive adhesive composition according to claim 3, comprising a condensation reaction product of said component (A), optionally said component (A'), and said component (B), and further comprising said component (F).

6. (E)R ３ ３ SiO １／２ Units and SiO ４／２ units, and has a hydroxyl group and / or an alkoxy group having 1 to 6 carbon atoms bonded to a silicon atom, (R ３ ３ SiO １／２ Unit) / (SiO ４／２ The organopolysiloxane resin (wherein R ３ are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, a hydroxyl group, or an alkoxy group having 1 to 6 carbon atoms; 2. The silicone pressure-sensitive adhesive composition according to claim 1, further comprising an organopolysiloxane resin that does not contain alkenyl groups or that contains alkenyl groups in such an amount that the total amount of alkenyl groups in the organopolysiloxane resin is less than 0.005 mol / 100 g, and that has a weight-average molecular weight of less than 5,000 as measured by gel permeation chromatography relative to standard polystyrene standards, in an amount of 0.01 to 35 mass %, relative to the total mass of the silicone pressure-sensitive adhesive composition.

7. 7. The silicone pressure-sensitive adhesive composition according to claim 6, comprising a condensation reaction product of the component (A), optional component (A'), the component (B), and the component (E).

8. (E)R ３ ３ SiO １／２ Units and SiO ４／２ units, and has a hydroxyl group and / or an alkoxy group having 1 to 6 carbon atoms bonded to a silicon atom, (R ３ ３ SiO １／２ Unit) / (SiO ４／２ The organopolysiloxane resin (wherein R ３ and each independently represent a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, a hydroxyl group, or an alkoxy group having 1 to 6 carbon atoms), wherein the organopolysiloxane resin does not contain alkenyl groups or contains alkenyl groups in such an amount that the total amount of alkenyl groups in the organopolysiloxane resin is less than 0.005 mol / 100 g, and wherein the organopolysiloxane resin has a weight average molecular weight of less than 5,000 as measured by gel permeation chromatography relative to standard polystyrene standards, in an amount of 0.01 to 35 mass %, relative to the total mass of the silicone pressure-sensitive adhesive composition.

9. 9. The silicone pressure-sensitive adhesive composition according to claim 8, comprising a condensation reaction product of the component (A), optionally the component (A'), the component (B), the component (E), and the component (F).

10. 9. The silicone pressure-sensitive adhesive composition according to claim 8, comprising a condensation reaction product of the component (A), optionally the component (A'), the component (B), and the component (E), and further comprising the component (F).

11. 2. The silicone pressure-sensitive adhesive composition according to claim 1, wherein the component (A) is represented by the following formula (1): 【Chemistry 1】 (In the formula, R １ are each independently a hydroxyl group, an alkoxy group having 1 to 6 carbon atoms, or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, provided that R １ at least one of R is an alkenyl-containing organic group having 2 to 10 carbon atoms; １ the ratio of the number of hydroxyl groups to the total number of groups is 10% or less, the alkenyl group content in the organopolysiloxane is 0.0001 to 0.03 mol / 100 g, and a is a positive number such that a solution of the organopolysiloxane in toluene to a concentration of 30% by mass has a viscosity at 25°C of 1,000 to 200,000 mPa s.

12. The component (F) further comprises R ５ R ６ SiO ２／２ units (wherein R ５ is the above R other than an alkenyl group. ３ and R ６ is an alkenyl group having 2 to 10 carbon atoms), (R ５ R ６ SiO ２／２ Unit) / (SiO ４／２ 4. The silicone pressure-sensitive adhesive composition according to claim 3, wherein the organopolysiloxane resin has a molar ratio, expressed as ##STR1## of 0.01 to 0.

5.

13. The component (F) further comprises R ５ R ６ SiO ２／２ units (wherein R ５ is the above R other than an alkenyl group. ３ and R ６ is an alkenyl group having 2 to 10 carbon atoms), (R ５ R ６ SiO ２／２ Unit) / (SiO ４／２ 9. The silicone pressure-sensitive adhesive composition according to claim 8, wherein the organopolysiloxane resin has a molar ratio, expressed as ##STR1## of 0.01 to 0.

5.

14. The silicone pressure-sensitive adhesive composition according to any one of claims 1 to 13, wherein the adhesive strength of a 40 µm-thick cured layer formed by curing the silicone pressure-sensitive adhesive composition to a silicone rubber sheet is 3.0 N / 25 mm or more, as measured using a 180° peel test method at a tensile speed of 300 mm / min.

15. A cured product obtained by curing the silicone pressure-sensitive adhesive composition according to any one of claims 1 to 13.

16. The cured product according to claim 15, wherein the adhesive layer made of the cured product has a storage modulus G' at 25°C of 1.00 MPa or more.

17. The cured product according to claim 15, wherein the adhesive layer made of the cured product has a storage modulus G' at 80°C of 0.10 MPa or more.

18. An adhesive tape comprising a substrate and an adhesive layer formed on at least one surface of the substrate, the adhesive layer being the cured product according to claim 15.

19. An adhesive film comprising a substrate and an adhesive layer formed on at least one surface of the substrate, the adhesive layer being the cured product according to claim 15.

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