Curable compositions for silicone pressure-sensitive adhesives

Abstract

The curable composition comprises: (A) a polydiorganosiloxane component comprising (A1) greater than 3.1% to 20% by weight of an aliphatically unsaturated polydiorganosiloxane polymer; and (A3) a hydroxyl-terminated polydiorganosiloxane gum having the unit formula (A-III); and (B) a polyorganosilicate resin component comprising (B1) a capped resin; and (B2) greater than 18.53% to 54.3% by weight of an uncapped resin, wherein the weight ratio of uncapped resin (B2) to capped resin (B1) is greater than 0.51 to 58.82; and the weight ratio of component (A) and component (B) is 1. (C) a polyorganohydrogensiloxane present in an amount to provide a molar ratio of silicon-bonded hydrogen atoms to alkenyl groups, relative to the curable composition, of from 5 to 50; (D) a hydrosilylation reaction catalyst in an amount sufficient to provide from 1 to 1000 ppm of platinum group metal; and (E) a condensation reaction catalyst, wherein the alkenyl group content in the curable composition is from 0.017 weight percent to 0.089 weight percent, the weight percent values ​​being based on the total weight of components (A), (B), (C), (D) and (E), unless otherwise specified.

Description

[Technical Field]

[0001] The present invention relates to curable compositions and methods for preparing curable compositions. In particular, the present invention relates to hydrosilylation and condensation curable compositions that cure to form silicone pressure sensitive adhesives. [Background technology]

[0002] Introduction Protective films and carrier tapes are two major applications of silicone pressure-sensitive adhesives in the electronics manufacturing industry. During the fabrication of electronic devices, various components of the protective film and carrier tape are typically laminated together with an adherend to form multiple layers. It is important that the layers adhere to each other and avoid damage that could cause component failure. The multiple layers typically include a protective film that adheres to an adherend (e.g., graphite sheet, copper foil, or ultra-thin double-sided tape) used in the manufacture of electronic devices to protect the adherend from scratches and other damage during processing and / or shipping. It is desirable for such a protective film to peel cleanly from the adherend without leaving any noticeable residue on the end user of the electronic device. This typically requires a protective film with low adhesion to the adherend, e.g., adhesion to stainless steel of less than 10 grams per inch according to ASTM D3330. However, such low-adhesion silicone protective films can suffer from the drawback of difficulty in forming rapid and strong bonds to other layers in the manufacture of home appliances.

[0003] Therefore, there is a need in the industry for a silicone pressure sensitive adhesive that can adhere to low adhesion silicone protective films with desirable adhesive properties. Summary of the Invention

[0004] The present invention provides novel curable compositions that can cure to cured products that achieve high adhesion (i.e., 400 grams per inch (g / in) or greater) to low-adhesion silicone protective films. A "low-adhesion silicone protective film" refers to a protective film, other than the silicone pressure-sensitive adhesive of the present invention, that has a low-adhesion silicone pressure-sensitive adhesive with an adhesion of less than 10 g / in to stainless steel. Adhesion properties are measured using an AR 1500 adhesion / peel tester in accordance with ASTM D3330. The curable compositions of the present invention contain novel combinations of an aliphatically unsaturated polydiorganosiloxane polymer, a hydroxyl-terminated polydiorganosiloxane gum, a capped polyorganosilicate resin, an uncapped polyorganosilicate resin, a polyorganohydrogensiloxane, a hydrosilylation reaction catalyst, and a condensation reaction catalyst, all at specific concentrations. The curable compositions of the present invention are particularly useful for forming silicone pressure-sensitive adhesives. The curable composition can be cured by both a hydrosilylation reaction and a condensation reaction (i.e., a hydrosilylation reaction and a condensation reaction curable composition) to prepare a pressure-sensitive adhesive (also called a "hydrosilylation / condensation dual-cure PSA").

[0005] In a first aspect, the present invention provides a curable composition comprising: (A) a polydiorganosiloxane component, (A1) greater than 3.1 weight percent to 20 weight percent of an aliphatically unsaturated polydiorganosiloxane polymer of formula (AI), R M (3-c) R U c SiO-(R U R M SiO) a -(R M 2SiO) b -SiR U d R M (3-d) (AI) In the formula, each R Mare independently selected from the group consisting of monovalent hydrocarbon groups of 1 to 30 carbon atoms free of aliphatic unsaturation and monovalent halogenated hydrocarbon groups free of aliphatic unsaturation, and each R U are independently alkenyl groups, and the subscripts a, b, c, and d are a≧0, b>0, c is 0 or 1, and d is 0 or 1, and the amount (a+b) is from 100 to 2000 and has an average value such that the amount (a+c+d)≧2; (A3) A hydroxyl-terminated polydiorganosiloxane gum of the unit formula (A-III): {(HO)R M 2SiO 1 / 2}2(R M 2SiO 2 / 2 ) e (A-III) In the formula, each R M are independently selected from the group consisting of monovalent hydrocarbon radicals of 1 to 30 carbon atoms free of aliphatic unsaturation and monovalent halogenated hydrocarbon radicals free of aliphatic unsaturation, and the subscript e has a value sufficient to impart to the (A3) hydroxyl-terminated polydiorganosiloxane gum a plasticity of 20 mils (0.51 mm) to 80 mils (2.03 mm), the plasticity being measured in accordance with ASTM D926 by applying a 1 kg load to a spherical sample weighing 4.2 g for 3 minutes at 25°C, the results being measured in thousandths of an inch (mil), the procedure being in accordance with ASTM D926 D926, which comprises a polydiorganosiloxane component comprising: a hydroxyl-terminated polydiorganosiloxane gum (A3) present in an amount to provide a weight ratio of hydroxyl-terminated polydiorganosiloxane gum (A3) to aliphatically unsaturated polydiorganosiloxane polymer (A1) of 0.89:1 to 9.33:1; (B) a polyorganosilicate resin component, (B1) Unit formula (BI):(R M 3SiO 1 / 2 ) z (SiO 4 / 2 ) o Z f wherein R Mare independently selected from the group consisting of monovalent hydrocarbon groups of 1 to 30 carbon atoms free of aliphatic unsaturation and monovalent halogenated hydrocarbon groups free of aliphatic unsaturation, each Z is independently a hydrolyzable group, subscript f ranges from 0 to a value sufficient to provide the capped resin with a hydrolyzable group content of up to 2%, and subscripts z and o have values such that o > 1, z > 4, and the amount (o + z) has a value sufficient to provide the capped resin with a number average molecular weight of 500 g / mol to less than 7,000 g / mol; (B2) 18.53 weight percent to 54.3 weight percent of the unit formula (B-II): (R M 3SiO 1 / 2 ) z’ (SiO 4 / 2 ) o’ Z f’ an uncapped resin of the formula R M are independently selected from the group consisting of monovalent hydrocarbon groups of 1 to 30 carbon atoms free of aliphatic unsaturation and monovalent halogenated hydrocarbon groups free of aliphatic unsaturation; each Z is independently a hydrolyzable group; subscript f' has a value sufficient to provide the uncapped resin with a hydrolyzable group content of greater than 3% to 10%; and subscripts z' and o' have values such that o' > 1, z' > 4, and the amount (o' + z') has a value sufficient to provide the uncapped resin with a number average molecular weight of 500 g / mol to less than 7,000 g / mol; the weight ratio of uncapped resin (B2) to capped resin (B1) is greater than 0.51 and less than 58.82; a polyorganosilicate resin component, wherein the (A) polydiorganosiloxane component and the (B) polyorganosilicate resin component are present in amounts to provide a weight ratio of (B):(A) of from 1.2:1 to less than 1.62:1; (C) a polyorganohydrogensiloxane of the unit formula (CI), (R M 3SiO 1 / 2 ) p (R M 2SiO2 / 2 ) q (R M SiO 3 / 2 ) r (SiO 4 / 2 ) s (R M HSiO 2 / 2 ) t (R M 2HSiO 1 / 2 ) u (CI) In the formula, R M are as defined above in formula (AI), and the subscripts p, q, r, s, t, and u are such that p≧0, q≧0, r≧0, s≧0, t≧0, u≧0, (t+u)≧2, and the amount (p+q+r+s+t+u) has values sufficient to provide a polyorganohydrogensiloxane having a degree of polymerization from 5 to 100, which is present in an amount to provide the curable composition with a molar ratio of silicon-bonded hydrogen atoms to alkenyl groups from 5 to 50; and (D) a hydrosilylation catalyst in an amount sufficient to provide 1 to 1000 ppm of a platinum group metal; (E) a condensation reaction catalyst in which the content of alkenyl groups in the curable composition is in the range of 0.017 weight percent to 0.089 weight percent; The weight percentages are based on the combined weight of components (A), (B), (C), (D) and (E).

[0006] In a second aspect, the present invention is a process for preparing the curable composition of the first aspect, the process comprising: i) mixing the hydroxyl-terminated polydiorganosiloxane gum (A3), the uncapped resin (B2), and the condensation reaction catalyst (E); and ii) further mixing the resulting mixture obtained from step i) with the aliphatically unsaturated polydiorganosiloxane polymer (A1), the capped resin (B1), the polyorganohydrogensiloxane (C), and the hydrosilylation reaction catalyst (D), thereby forming a curable composition.

[0007] In a third aspect, the present invention is an adhesive article comprising a substrate and a silicone pressure sensitive adhesive on at least one surface of the substrate, the silicone pressure sensitive adhesive being the cured product of the curable composition of the first aspect.

[0008] In a fourth aspect, the present invention is a method of making an adhesive article, optionally comprising: (1) treating a surface of a substrate; (2) coating at least one surface of the substrate with the curable composition of the first aspect; and (3) curing the curable composition. [Brief explanation of the drawings]

[0009] [Figure 1] 1 shows a partial cross-sectional view of an adhesive article 100. The adhesive article comprises a pressure-sensitive adhesive 102 prepared by curing a curable composition described herein on a surface 101 of a film substrate 101. The article 100 further comprises a low-adhesion silicone protective film 200 adhered to the opposing surface of the pressure-sensitive adhesive 102. DETAILED DESCRIPTION OF THE INVENTION

[0010] Test methods, unless a date is given with the test method number, refer to the test method most recent as of the priority date of this document. Reference to a test method includes both a reference to the testing society and the test method number. The following test method abbreviations and identifiers apply herein: ASTM stands for ASTM International methods.

[0011] Products identified by trade names refer to compositions available under those trade names as of the priority date of this document.

[0012] "And / or" means "and, or alternatively." All ranges are inclusive of the endpoints unless otherwise indicated.

[0013] "Viscosity" for polydiorganosiloxanes (e.g., component (A1) below) is measured at 25 degrees Celsius (°C) using rotational viscosimetry with a Brookfield DV-II viscometer in accordance with ASTM 1084, unless otherwise specified.

[0014] The "plasticity" of polydiorganosiloxane gum is measured in accordance with ASTM D926 by applying a 1 kilogram (kg) load to a spherical sample weighing 4.2 grams (g) for 3 minutes (min) at 25°C, with the results measured in thousandths of an inch (mils), and the procedure is based on ASTM D926 unless otherwise specified.

[0015] The chemical structure of polydiorganosiloxane, polyorganosilicate resin, or polyorganohydrogensiloxane is similar to that of standard 1 H, 13 C and 29 It is determined by Si nuclear magnetic resonance (NMR) analysis.

[0016] "Adhesion" properties are measured using an AR 1500 adhesion / peel tester according to ASTM D3330 unless otherwise specified.

[0017] Unless otherwise specified, number average molecular weight (Mn) refers to the number average molecular weight measured using gel permeation chromatography (GPC), and weight average molecular weight (Mw) refers to the weight average molecular weight measured using GPC. For example, a suitable GPC test method for measuring Mn and Mw is disclosed in Reference Example 1 of column 31 of U.S. Pat. No. 9,593,209.

[0018] The curable compositions of the present invention comprise components (A), (B), (C), (D), and (E), as well as optional components described below. The curable compositions comprise (A) a polydiorganosiloxane component (component (A)). Polydiorganosiloxane component (A) can comprise or consist of (A1) an aliphatically unsaturated polydiorganosiloxane polymer (also known as a "Vi polymer") and (A3) a hydroxyl-terminated polydiorganosiloxane gum (also known as an "OH gum"), and optionally (A2) an aliphatically unsaturated polydiorganosiloxane gum (also known as a "Vi gum").

[0019] The aliphatically unsaturated polydiorganosiloxane polymer (A1) (component (A1)) has the formula (AI): R M (3-c) R U c SiO-(R U R M SiO) a -(R M 2SiO) b -SiR U d R M (3-d) (AI) wherein each R M are independently selected from the group consisting of monovalent hydrocarbon groups of 1 to 30 carbon atoms free of aliphatic unsaturation and monovalent halogenated hydrocarbon groups of 1 to 30 carbon atoms free of aliphatic unsaturation, and each R U are independently alkenyl groups, and the subscripts a, b, c, and d are such that a≧0, b>0, c is 0 or 1, d is 0 or 1, the amount (a+b) is 100 to 2000, and has an average value such that the amount (a+c+d)≧2. M Suitable monovalent hydrocarbon groups and monovalent halogenated hydrocarbon groups for each R are as defined below. M may have 1 to 30 carbon atoms, and can be 1 to 12 carbon atoms, 1 to 10 carbon atoms, 1 to 6 carbon atoms, 1 to 4 carbon atoms, 1 to 2 carbon atoms, or even 1 carbon atom. Mcan be an alkyl group, an aryl group, or an aralkyl group as defined below. Desirably, each R M is an alkyl group of 1 to 6 carbon atoms or an aryl group, e.g., phenyl. More preferably, each R M is methyl. Each R U may independently be an alkenyl group, as defined below. U may have 2 to 12 carbon atoms, 2 to 10 carbon atoms, 2 to 6 carbon atoms, 2 to 4 carbon atoms, or even 2 carbon atoms. Desirably, each R U are independently selected from the group consisting of vinyl, allyl, and hexenyl. Alternatively, the amount (a+b) is 300 millipascals or less. * seconds (milliPascal * The viscosity may be sufficient to impart to the aliphatic unsaturated polydiorganosiloxane polymer a viscosity of from 350 mPa·s to 90,000 mPa·s, from 400 mPa·s to 80,000 mPa·s, or from 450 mPa·s to 70,000 mPa·s. Desirably, the aliphatic unsaturated polydiorganosiloxane polymer (A1) has a viscosity of from 450 to 40,000 mPa·s. Alternatively, the amount (a+b) may have a value sufficient to provide the aliphatically unsaturated polydiorganosiloxane polymer with an Mn of 5,000 grams per mole (g / mol) to 100,000 g / mol, 10,000 g / mol to 100,000 g / mol, 11,000 g / mol to 90,000 g / mol, or 11,500 g / mol to 90,000 g / mol; desirably, the aliphatically unsaturated polydiorganosiloxane polymer has an Mn of 10,000 g / mol to 40,000 g / mol as measured by GPC. Desirably, in formula (AI), each R M are independently alkyl groups of 1 to 6 carbon atoms, such as methyl, and each R U are independently selected from the group consisting of vinyl, allyl, and hexenyl, and the amount (a+b) has a value sufficient to impart a viscosity of 300 mPa·s to 100,000 mPa·s to the aliphatically unsaturated polydiorganosiloxane polymer.

[0020] "Alkyl" means a cyclic, branched, or unbranched saturated monovalent hydrocarbon group. Alkyl is exemplified by, but not limited to, methyl, ethyl, propyl (e.g., isopropyl and / or n-propyl), butyl (e.g., isobutyl, n-butyl, tert-butyl, and / or sec-butyl), pentyl (e.g., isopentyl, neopentyl, and / or tert-pentyl), hexyl, heptyl, octyl, nonyl, and decyl, as well as branched alkyl groups of 6 or more carbon atoms and cyclic alkyl groups such as cyclopentyl and cyclohexyl. Alkyl groups have 1 to 12 carbon atoms and can be 1 to 10 carbon atoms, 1 to 6 carbon atoms, 1 to 4 carbon atoms, 1 to 2 carbon atoms, or even 1 carbon atom. "Aryl" means a fully unsaturated cyclic hydrocarbon group. Aryl is exemplified by, but not limited to, cyclopentadienyl, phenyl, anthracenyl, and naphthyl. Monocyclic aryl groups can have 5 to 9 carbon atoms, alternatively 6 to 7 carbon atoms, alternatively 5 to 6 carbon atoms. Polycyclic aryl groups can have 10 to 17 carbon atoms, alternatively 10 to 14 carbon atoms, alternatively 12 to 14 carbon atoms. "Aralkyl" refers to an alkyl group having a pendant and / or terminal aryl group, or an aryl group having a pendant alkyl group. Exemplary aralkyl groups include tolyl, xylyl, benzyl, phenylethyl, phenylpropyl, and phenylbutyl.

[0021] "Alkenyl" means a branched or unbranched monovalent hydrocarbon group having one or more carbon-carbon double bonds. Suitable alkenyl groups are exemplified by vinyl, allyl, butenyl, pentenyl, hexenyl, and heptenyl (including branched and straight-chain isomers of 3 to 7 carbon atoms); and cyclohexenyl. Desirably, the alkenyl group is selected from the group consisting of vinyl, allyl, or hexenyl.

[0022] "Monovalent hydrocarbon group" means a monovalent group consisting of hydrogen and carbon atoms. Monovalent hydrocarbon groups include alkyl, aralkyl, alkenyl, and cycloalkyl groups, as defined above.

[0023] "Monovalent halogenated hydrocarbon group" means a monovalent hydrocarbon group in which one or more hydrogen atoms bonded to a carbon atom have been replaced with a halogen atom. Halogenated hydrocarbon groups include haloalkyl groups, halogenated carbocyclic groups, and haloalkenyl groups. Haloalkyl groups include fluorinated alkyl groups and fluorinated cycloalkyl groups, such as trifluoromethyl (CF), fluoromethyl, trifluoroethyl, 2-fluoropropyl, 3,3,3-trifluoropropyl, 4,4,4-trifluorobutyl, 4,4,4,3,3-pentafluorobutyl, 5,5,5,4,4,3,3-heptafluoropentyl, 6,6,6,5,5,4,4,3,3-nonafluorohexyl, 8,8,8,7,7-pentafluorooctyl, 2,2-difluorocyclopropyl, 2,3-difluorocyclobutyl, 3,4-difluorocyclohexyl, and 3,4-difluoro-5-methylcycloheptyl; and chlorinated alkyl groups and chlorinated cycloalkyl groups, such as chloromethyl, 3-chloropropyl, 2,2-dichlorocyclopropyl, and 2,3-dichlorocyclopentyl. Haloalkenyl groups include chloroallyl groups.

[0024] The aliphatically unsaturated polydiorganosiloxane polymer (A1) may comprise one polydiorganosiloxane of formula (AI) or a combination of two or more polydiorganosiloxanes of formula (AI) that may differ in one or more properties such as viscosity, molecular weight, structure, siloxane units and sequence. Aliphatically unsaturated polydiorganosiloxane polymers suitable for use as component (A1) in the curable composition may include any one, or any combination of two or more, of the following polydiorganosiloxanes: i) dimethylvinylsiloxy-terminated polydimethylsiloxane, ii) dimethylvinylsiloxy-terminated poly(dimethylsiloxane / methylphenylsiloxane), iii) dimethylvinylsiloxy-terminated poly(dimethylsiloxane / diphenylsiloxane), iv) phenyl, methyl, vinyl-siloxy-terminated polydimethylsiloxane, v) dimethylhexenylsiloxy-terminated polydimethylsiloxane, iv) dimethylvinylsiloxy-terminated poly(dimethylsiloxane / methylhydrogensiloxane), and vii) trimethylsiloxy-terminated poly(dimethylsiloxane / vinylmethylhydrogensiloxane). Desirably, the aliphatically unsaturated polydiorganosiloxane polymer is selected from the group consisting of bis-vinyldimethylsiloxy-terminated polydimethylsiloxane, bis-vinyldimethylsiloxy-terminated polydimethylsiloxane, bis-vinyldimethylsiloxy-terminated polydimethylsiloxane, dimethylvinylsiloxy-terminated poly(dimethylsiloxane / methylhydrogensiloxane), trimethylsiloxy-terminated poly(dimethylsiloxane / vinylmethylhydrogensiloxane), or mixtures thereof. Methods for preparing aliphatically unsaturated polydiorganosiloxanes, such as the hydrolysis and condensation of the corresponding organohalosilanes or the equilibration of cyclic polydiorganosiloxanes, are known in the art.

[0025] The aliphatically unsaturated polydiorganosiloxane polymer (A1) may be present in a concentration of greater than 3.1 (>3.1) weight percent (wt%), based on the combined weight of components (A), (B), (C), (D), and (E), such as 3.3 wt% or greater, 3.5 wt% or greater, 3.7 wt% or greater, 3.9 wt% or greater, 4.0 wt% or greater, 4.1 wt% or greater, 4.2 wt% or greater, 4.3 wt% or greater, 4.4 wt% or greater, 4.5 wt% or greater, 4.6 wt% or greater, 4.7 wt% or greater, 4.8 wt% or greater, 4.9 wt% or greater, or even greater than 3.1 wt%, based on the combined weight of components (A), (B), (C), (D), and (E). can be 5% or more, but generally is 20% or less by weight, 19.8% or less, 19.5% or less, 19.1% or less, 18% or less, 17% or less, 16.4% or less, 16% or less, 15% or less, 14% or less, 11% or less, 10% or less, 9.1% or less, 8% or less, 5% or less, or even 4.9% or less by weight, and desirably the aliphatically unsaturated polydiorganosiloxane polymer is present in a concentration of 5% to 16% by weight.

[0026] Polydiorganosiloxane component (A) may or may not contain an aliphatically unsaturated polydiorganosiloxane gum (component (A2)) of formula (A-II): R M (3-c’) R U c’ SiO-(R U R M SiO) a’ -(R M 2SiO) b’ -SiR U d’ R M (3-d’) (A-II) In the formula, each R M is as defined above in formula (AI), and each R Uare as defined above in formula (AI), and subscripts a', b', c', and d' are such that a'≧0, subscript b'>0, subscript c' is 0 or 1, and subscript d' is 0 or 1; (a'+c'+d)≧2; and the amount (a'+b') has an average value such that it has a value sufficient to impart to the (A-2) aliphatically unsaturated polydiorganosiloxane gum a plasticity of from 20 mils (0.51 millimeters (mm)) to 80 mils (2.03 mm), from 30 mils (0.76 mm) to 70 mils (1.78 mm), or from 50 mils (1.27 mm) to 65 mils (1.65 mm), where plasticity is measured in accordance with ASTM D926 (further details provided above). Typically, the quantity (a'+b') may have a value of more than 2000, and may be 3000 or more, 4000 or more, or even 5000 or more.

[0027] Aliphatically unsaturated polydiorganosiloxane gums are known in the art and can be prepared by methods such as hydrolysis and condensation of the corresponding organohalosilanes or equilibration of cyclic polydiorganosiloxanes. Aliphatically unsaturated polydiorganosiloxane gum (A2) can include a combination of two or more polydiorganosiloxane gums of unit formula (A-II), which may differ in one or more properties, such as plasticity, structure, siloxane units, and arrangement. Aliphatically unsaturated polydiorganosiloxane gums suitable for use as component (A2) in the curable composition can include any one, or any combination of two or more, of the following polydiorganosiloxane gums: i) dimethylvinylsiloxy-terminated polydimethylsiloxane; ii) dimethylvinylsiloxy-terminated poly(dimethylsiloxane / methylphenyl)siloxane; iii) dimethylvinylsiloxy-terminated poly(dimethylsiloxane / diphenyl)siloxane; iv) phenyl, methyl, vinyl-siloxy terminated polydimethylsiloxanes; v) dimethylhexenylsiloxy-terminated polydimethylsiloxane; vi) dimethylhexenylsiloxy-terminated poly(dimethylsiloxane / methylphenyl)siloxane, and vii) Dimethylvinylsiloxy-terminated poly(dimethylsiloxane / diphenyl)siloxane.

[0028] Desirably, the polydiorganosiloxane gum is selected from the group consisting of i) dimethylvinylsiloxy-terminated polydimethylsiloxane, v) dimethylhexenylsiloxy-terminated polydimethylsiloxane, or mixtures thereof.

[0029] The aliphatically unsaturated polydiorganosiloxane gum (A2) may be present in a concentration of greater than or equal to zero, and can be greater than zero (greater than 0), but at the same time is generally 7% by weight or less, and can be 6% by weight or less, 5% by weight or less, 3% by weight or less, 1.1% by weight or less, 1% by weight or less, or even 0.1% by weight or less, based on the combined weight of components (A), (B), (C), (D), and (E). Alternatively, the aliphatically unsaturated polydiorganosiloxane gum (A2) may be present in an amount to provide a combined concentration of the aliphatically unsaturated polydiorganosiloxane polymer (A1) and the aliphatically unsaturated polydiorganosiloxane gum (A2) of greater than 3.1% by weight, based on the combined weight of components (A), (B), (C), (D), and (E), such as 3.3% by weight or greater, 3.5% by weight or greater, 3.7% by weight or greater, 3.9% by weight or greater, 4.0% by weight or greater, 4.1% by weight or greater, 4.2% by weight or greater, 4.3% by weight or greater, 4.4% by weight or greater, 4.5% by weight or greater, 4.6% by weight or greater, 4.7% by weight or greater, 4.8% by weight or greater, 4.9 ... % or more, 4.5% or more, 4.6% or more, 4.7% or more, 4.8% or more, or even 4.9% or more by weight, but at the same time generally not more than 20% by weight, and can be not more than 19.8% by weight, not more than 19.5% by weight, not more than 19.1% by weight, not more than 18% by weight, not more than 17% by weight, not more than 16.4% by weight, not more than 15% by weight, not more than 14% by weight, not more than 11% by weight, not more than 10% by weight, not more than 9.1% by weight, not more than 8% by weight, not more than 5% by weight, or even not more than 4.9% by weight.

[0030] The polydiorganosiloxane component (A) also includes (A3) a hydroxyl-terminated polydiorganosiloxane gum (“OH gum”, component (A3)) of unit formula (A-III): {(HO)R M 2SiO 1 / 2}2(R M 2SiO 2 / 2 ) e (A-III) In the formula, each R M is as defined above in formula (AI), and the subscript e has a value sufficient to impart to the (A3) hydroxyl-terminated polydiorganosiloxane gum a plasticity of 20 mils (0.51 mm) to 80 mils (2.03 mm), and can be 30 mils (0.76 mm) or more, 50 mils (1.27 mm) or more, or even 53 mils (1.27 mm) or more, while simultaneously being 70 mils (1.78 mm) or less, 65 mils (1.65 mm) or less, or even 60 mils (1.65 mm), the plasticity being measured in accordance with ASTM D926 (further details provided above). Alternatively, the subscript e can have a value sufficient to impart to the hydroxyl-terminated polydiorganosiloxane gum an Mn of 200,000 g / mol or more, as measured by GPC. Desirably, in unit formula (A-III), each R M are independently alkyl groups of 1 to 6 carbon atoms, such as methyl, and each R U are independently selected from the group consisting of vinyl, allyl, and hexenyl, and the subscript e is sufficient to provide a hydroxyl-terminated polydiorganosiloxane gum having a plasticity of 30 mils (0.76 mm) to 70 mils (1.78 mm).

[0031] Hydroxyl-terminated polydiorganosiloxane gums suitable for the present invention are known in the art and can be prepared by methods such as hydrolysis and condensation of the corresponding organohalosilanes or equilibration of cyclic polydiorganosiloxanes. The hydroxyl-terminated polydiorganosiloxane gum (A3) can comprise one polydiorganosiloxane gum of formula (A-III) or a combination of two or more polydiorganosiloxane gums that may differ in properties such as plasticity, structure, and arrangement. Suitable hydroxyl-terminated polydiorganosiloxane gums for use as component (A3) can include any one, or any combination of two or more, of the following polydiorganosiloxanes: i) bis-hydroxyl-terminated polydimethylsiloxane, ii) bis-hydroxyl-terminated poly(dimethylsiloxane / methylphenylsiloxane), iii) bis-hydroxyl-terminated poly(dimethylsiloxane / diphenylsiloxane), and iv) phenyl, methyl, hydroxyl-siloxy-terminated polydimethylsiloxane. Desirably, the hydroxyl-terminated polydiorganosiloxane gum (A3) includes bis-hydroxyl-terminated polydimethylsiloxane.

[0032] The hydroxyl-terminated polydiorganosiloxane gum (A3) is present in the curable composition at a concentration of 17.67 weight percent or greater, based on the combined weight of components (A), (B), (C), (D), and (E), and can be 18 weight percent or greater, 19 weight percent or greater, 20 weight percent or greater, 21 weight percent or greater, 22 weight percent or greater, 22.5 weight percent or greater, 23 weight percent or greater, 23.5 weight percent or greater, 24 weight percent or greater, or even 24.5 weight percent or greater, but generally not greater than 36.2 weight percent. % by weight or less, and can be 36% by weight or less, 35.5% by weight or less, 35.1% by weight or less, 35% by weight or less, 34.6% by weight or less, 34.5% by weight or less, 34% by weight or less, 33.5% by weight or less, 33% by weight or less, 32.5% by weight or less, 32% by weight or less, 31.5% by weight or less, 31% by weight or less, 30% by weight or less, or even 29.5% by weight or less, desirably 17.67% by weight to 36.2% by weight, and more desirably 20% by weight to 30% by weight.

[0033] The aliphatic unsaturated polydiorganosiloxane polymer (A1) and the hydroxyl-terminated polydiorganosiloxane gum (A3) may have a weight ratio of hydroxyl-terminated polydiorganosiloxane gum (A3) to aliphatic unsaturated polydiorganosiloxane polymer (A1) (the "A3:A1 ratio") of 0.89:1 or greater, such as 1:1 or greater, 1.1:1 or greater, 1.2:1 or greater, 1.3:1 or greater, 1.5:1 or greater, 1.8:1 or greater, 2.0:1 or greater, 3.0:1 or greater, 4.0:1 or greater, 5.0:1 or greater, 6.0:1 or greater, 7.0:1 or greater, 8.0:1 or greater, 9.0:1 or greater, 10.0:1 or greater, 11.0:1 or greater, 12.0:1 or greater, 13.0:1 or greater, 14.0:1 or greater, 15.0:1 or greater, 16.0:1 or greater, 17.0:1 or greater, 18.0:1 or greater, 19.0:1 or greater, 20.0:1 or greater, 21.0:1 or greater, 22.0:1 or greater, 23.0:1 or greater, 24.0:1 or greater, 25.0:1 or greater, 26.0:1 or greater, 27.0:1 or greater, 28.0:1 or greater, 29.0:1 or greater, 30.0:1 or greater, 31.0:1 or greater, 32.0:1 or greater, 33.0:1 or greater, 34.0:1 or greater, 35.0:1 or greater, 36.0:1 or greater, 37.0:1 or The A3:A1 ratio can be 9.33:1 or greater, 2.5:1 or greater, 3.0:1 or greater, 3.5:1 or greater, or even 7.2:1 or greater, but generally is 9.33:1 or less, and can be 9.0:1 or less, 8.5:1 or less, 8.0:1 or less, 7.5:1 or less, 7.3:1 or less, 6:1 or less, 5:1 or less, 4.0:1 or less, or even 3.6:1 or less, and desirably can be present in an amount such that the A3:A1 ratio is in the range of 1:1 to 5:1.

[0034] The curable composition further comprises (B) a polyorganosilicate resin component (component (B)), which comprises or consists of (B1) a capped resin and (B2) an uncapped resin, represented by formula R M 3SiO 1 / 2 (In the formula, each R M is as defined above in formula (AI), and a monofunctional unit ("M" unit) of formula SiO 4 / 2 Polyorganosilicate resins containing tetrafunctional silicate units ("Q" units) of the formula: M At least one third or at least two thirds of the groups are alkyl groups, e.g., methyl groups. The M units are (MeSiO 1 / 2 ) and (Me2PhSiO 1 / 2 ), where Me represents methyl and Ph represents phenyl. The polyorganosilicate resins are soluble in solvents such as those described below, exemplified by liquid hydrocarbons such as benzene, toluene, xylene, and heptane, or in liquid organosilicon compounds such as low viscosity linear and cyclic polydiorganosiloxanes.

[0035] When prepared, the polyorganosilicate resin contains the M and Q units described above, and the polyorganosiloxane further contains units having silicon-bonded hydroxyl groups, and has the formula Si(OSiR M 3)4[wherein, R M is as defined above.], for example, the neopentamer may be tetrakis(trimethylsiloxy)silane. 29 Si NMR spectroscopy can be used to measure the hydroxyl (OH) content and the molar ratio of M and Q units, which is expressed as {M(resin)} / {Q(resin)}, excluding the M and Q units from the neopentamer. The "M:Q ratio" refers to the molar ratio of the total number of triorganosiloxy groups (M units) in the resinous portion of a polyorganosilicate resin to the total number of silicate groups (Q units) in the resinous portion. The M:Q ratio may be from 0.5:1 to 1.5:1.

[0036] The Mn of the polyorganosilicate resin is determined by the R M The Mn of a polyorganosilicate resin varies depending on various factors, such as the type of hydrocarbon group represented by the formula (I). The Mn of a polyorganosilicate resin refers to the number average molecular weight measured using GPC when the peak representing the neopentamer is excluded from the measurement. The Mn of a polyorganosilicate resin is 500 grams per mole (g / mol) to 5,000 g / mol, and can be 2,500 g / mol to 5,000 g / mol, 2,700 g / mol to 4,900 g / mol, or 2,700 g / mol to 4,700 g / mol. A suitable GPC test method for measuring Mn is disclosed in Reference Example 1 of U.S. Pat. No. 9,593,209, column 31.

[0037] U.S. Patent No. 8,580,073 (column 3, line 5 to column 4, line 31) and U.S. Patent Application Publication No. 2016 / 0376482 (paragraphs

[0023] to

[0026] ) are incorporated herein by reference for their disclosure of MQ resins, which are suitable polyorganosilicate resins for use in the hydrosilylation reaction curable compositions described herein. Polyorganosilicate resins can be prepared by any suitable method, such as cohydrolysis of the corresponding silanes or a silica hydrosol capping process. Polyorganosilicate resins can be prepared by a silica hydrosol capping process, such as those disclosed in U.S. Patent No. 2,676,182 to Daudt et al., U.S. Patent No. 4,611,042 to Rivers-Farrell et al., and U.S. Patent No. 4,774,310 to Butler et al. The Daudt et al. method involves reacting a silica hydrosol under acidic conditions with a hydrolyzable triorganosilane such as trimethylchlorosilane, a siloxane such as hexamethyldisiloxane, or a mixture thereof, and recovering a copolymer having M and Q units. The resulting copolymer generally contains 2 to 5 weight percent hydroxyl groups.

[0038] The intermediates used to prepare the polyorganosilicate resins can be triorganosilanes and silanes or alkali metal silicates containing four hydrolyzable substituents. The triorganosilanes have the formula R M 3SiX 1 (In the formula, R M is as above, and X 1 represents a hydrolyzable substituent such as halogen, alkoxy, acyloxy, hydroxyl, oximo, or ketoximo; alternatively, represents a hydrolyzable substituent such as halogen, alkoxy, or hydroxyl. Silanes with four hydrolyzable substituents have the formula SiX 2 4, wherein each X 2 is halogen, alkoxy, or hydroxyl. Suitable alkali metal silicates include sodium silicate.

[0039] The polyorganosilicate resin prepared as above is an uncapped resin (B2), which typically contains silicon-bonded hydroxyl groups, e.g., of the formula HOSi 3 / 2 and / or HOR M 2SiO 1 / 2 The uncapped resin may contain greater than 3% to 10% silicon-bonded hydroxyl groups (also known as silanol groups) as measured by NMR spectroscopy. In certain applications, it may be desirable for the amount of silicon-bonded hydroxyl groups to be 2% or less, alternatively less than 0.7%, alternatively less than 0.3%, alternatively less than 1%, or alternatively between 0.3% and 2%, forming a capped resin (B1). The silicon-bonded hydroxyl groups formed during the preparation of the polyorganosilicate resin can be converted to trihydrocarbonsiloxane groups or different hydrolyzable groups by reacting the silicone resin with a silane, disiloxane, or disilazane containing the appropriate terminal group, in a process known as capping. The silane containing the hydrolyzable group may be added in molar excess over the amount required to react with the silicon-bonded hydroxyl groups in the polyorganosilicate resin.

[0040] When the polyorganosilicate resin is a capped resin, the capped resin may have the formula HOSiO 3 / 2 and / or HOR M 2SiO 1 / 2 (In the formula, R M The polyorganosiloxane may contain 2% or less of units represented by the formula (wherein x is as defined above), and may contain 0.7% or less, or 0.3% or less, or may contain 0.3% to 0.8%. The concentration of silanol groups present in the polyorganosiloxane can be measured using NMR spectroscopy as described above.

[0041] The capped resin (B1) (also "capped MQ resin", component (B1)) has the unit formula (BI):(R M 3SiO 1 / 2 ) z (SiO 4 / 2 ) o Z fwherein each R M is as defined above in formula (AI), and each Z is independently a hydrolyzable group which may be selected from the group consisting of alkoxy, hydroxyl, or combinations thereof; the subscripts z and o have values such that o>1, z>4, and the amount (o+z) has a value sufficient to provide a capped resin having an Mn of from 500 g / mol to less than 7,000 g / mol, and can be 500 g / mol or more, 1,000 g / mol or more, or even 2900 g / mol or more, while at the same time exceeding 7,000 g / mol. The subscript f can be less than 5,000 g / mol, 4,700 g / mol, or even 4,100 g / mol, and the subscript f has a value sufficient to provide the capped resin with a hydrolyzable group content of 0-2%, and can be 0 or more, 0.3% or more, 0.7% or more, or even 0.8% or more, but simultaneously 2% or less, 1.9% or less, 1.8% or less, 1.7% or less, 1.6% or less, 1.5% or less, 1.4% or less, 1.3% or less, 1.2% or less, 1.1% or less, or even 1% or less. The percentage of hydrolyzable groups in the resin herein refers to the weight percentage of hydrolyzable groups relative to the resin weight, as determined by Fourier Transform Infrared (FTIR) spectroscopy. Typically, each Z is a hydroxyl (OH).

[0042] The capped resin (B1) may be present in a concentration of 0.9% by weight or greater, and can be 1% by weight or greater, 5% by weight or greater, 10% by weight or greater, 15% by weight or greater, 20% by weight or greater, 25% by weight or greater, 27% by weight or greater, 29% by weight or greater, or even 30% by weight or greater, based on the combined weight of components (A), (B), (C), (D), and (E), while generally being 35.9% by weight or less, 35% by weight or less, 34% by weight or less, 33% by weight or less, 32% by weight or less, 31% by weight or less, or even 30.5% by weight or less.

[0043] The uncapped resin (B2) ("uncapped MQ resin", component (B2)) has the unit formula (B-II): (R M3SiO 1 / 2 ) z’ (SiO 4 / 2 ) o’ Z f’ (B-II), wherein each R M is as defined above in formula (AI), each Z is as defined above, e.g., hydroxyl, and the subscripts z' and o' have values such that o' > 1, z' > 4, and the amount (o' + z') has a value sufficient to provide the uncapped resin with an Mn of from 500 g / mol to less than 7,000 g / mol, and can be 500 g / mol or more, 1,000 g / mol or more, 2,700 g / mol or more, or even 2,900 g / mol or more, but the same Sometimes, the subscript f' has a value sufficient to provide the uncapped resin with a hydrolyzable group content of greater than 3% (i.e., greater than 3%), and can be 3.1% or greater, 3.2% or greater, or even 3.4% or greater, while generally being 10% or less, 5% or less, or even 4% or less. Desirably, in unit formula (B-II), each R M is an independently selected alkyl group having 1 to 6 carbon atoms, such as methyl, each Z is OH, and the amount (z+o) has a value sufficient to provide an uncapped resin having an Mn of 2,900 g / mol to 5,000 g / mol.

[0044] The uncapped resin (B2) may be present in an amount greater than 18.53 wt.% (>18.53 wt.%), and can be 18.8 wt.% or greater, 19.0 wt.% or greater, 19.2 wt.% or greater, 19.5 wt.% or greater, 19.9 wt.% or greater, 22 wt.% or greater, 24 wt.% or greater, 24.5 wt.% or greater, 25 wt.% or greater, 28 wt.% or greater, 30 wt.% or greater, or even 32 wt.% or greater, based on the combined weight of components (A), (B), (C), (D), and (E), while generally being 54.3 wt.% or less, 54 wt.% or less, 53 wt.% or less, 52 wt.% or less, 51 wt.% or less, 50 wt.% or less, 49 wt.% or less, 48 wt.% or less, 47 wt.% or less, 46.5 wt.% or less, or even 46.3 wt.% or less.

[0045] The amount of capped and uncapped resins in the polyorganosilicate resin component may be sufficient to provide a weight ratio of uncapped resin (B2) to capped resin (B1), i.e., a (B2):(B1) ratio, of greater than 0.51 (>0.51), and may be 0.55 or greater, 0.6 or greater, 0.7 or greater, 0.8 or greater, 1.0 or greater, 1.2 or greater, 1.3 or greater, 1.4 or greater, 1.8 or greater, 2.0 or greater, or even 2.2 or greater, while generally not greater than 58.82, and may be 40 or less, 30 or less, 20 or less, 10 or less, 5 or less, 4.9 or less, or even 4.85 or less; desirably, the (B2):(B1) ratio is from 0.55 to 5, more desirably from 0.8 to 5.0.

[0046] The polydiorganosiloxane component (A) and the polyorganosilicate resin component (B) may be present in the curable composition in an amount sufficient to provide a weight ratio of polyorganosilicate resin component (B) to polydiorganosiloxane component (A), i.e., a (B):(A) ratio or R / P ratio, of 1.2:1 or greater, and may be 1.25:1 or greater, 1.28:1 or greater, 1.29:1 or greater, 1.30:1 or greater, 1.31:1 or greater, or even 1. It can be 4:1 or more, but at the same time, it is generally less than 1.62:1 (<1.62:1), and can be 1.60:1 or less, 1.58:1 or less, 1.56:1 or less, 1.54:1 or less, 1.53:1 or less, 1.52:1 or less, 1.50:1 or less, 1.49:1 or less, 1.45:1 or less, 1.44:1 or less, 1.42:1 or less, or even 1.4:1 or less, and desirably the R / P ratio is 1.2:1 to 1.5:1. For example, the R / P ratio can be the ratio of the total weight of components (B1) and (B2) to the total weight of components (A1) and (A3), and, if present, (A2).

[0047] The curable compositions of the present invention also include (C) a polyorganohydrogensiloxane ("SiH crosslinker", component (C)). The polyorganohydrogensiloxane acts as a crosslinker in the curable composition. The polyorganohydrogensiloxane may have two or more, or at least three silicon-bonded hydrogen atoms per molecule.

[0048] The polyorganohydrogensiloxane may comprise the unit formula (CI): (R M 3SiO 1 / 2 ) p (R M 2SiO 2 / 2 ) q (R M SiO 3 / 2 ) r (SiO 4 / 2 ) s (R M HSiO 2 / 2 ) t (R M 2HSiO 1 / 2 ) u (CI) In the formula, R M are as defined above in formula (AI), and the subscripts p, q, r, s, t, and u are such that p≧0, q≧0, r≧0, s≧0, t≧0, u≧0, (t+u)≧2, and the amount (p+q+r+s+t+u) has values sufficient to provide a polyorganohydrogensiloxane having a degree of polymerization of 5 to 100, or 10 to 60. The degree of polymerization can be determined according to the chemical structure and / or Mn of the polyorganohydrogensiloxane. Alternatively, the polyorganohydrogensiloxane may comprise a unit formula (C-2): (R M 3SiO 1 / 2 )2(R M 2SiO 2 / 2 ) aa (R M HSiO 2 / 2 ) bb (C-2) In the formula, each R M are independently selected from the group consisting of methyl and phenyl, the subscript aa is 0-30, and the subscript bb is 5-50.

[0049] Alternatively, the polyorganohydrogensiloxane is of formula (C-3), formula (C-4), or both (C-3) and (C-4): R M 3SiO(R M 2SiO) g (R M HSiO) h SiR M 3(C-3), R M 2HSiO(R M 2SiO) i (R M HSiO) j SiR M 2H (C-4),

[0050] In the above formulas (C-3) and (C-4), R Mare as above. The subscript g has an average value of 0 to 2000, the subscript h has an average value of 2 to 2000, the subscript i has an average value of 0 to 2000, and the subscript j has an average value of 0 to 2000.

[0051] The polyorganohydrogensiloxane (C) may have a silicon-bonded hydrogen content of 0.5% to 2% or 0.6% to 1.5%, where the silicon-bonded hydrogen (SiH) content ("SiH content") refers to the weight percentage of silicon-bonded hydrogen relative to the weight of the polyorganohydrogensiloxane and can be determined using Fourier transform infrared (FTIR) spectroscopy.

[0052] Suitable polyorganohydrogensiloxanes for use as component (C) may include any one, or any combination of two or more, of the following polyorganohydrogensiloxanes: i) bis-dimethylhydrogensiloxy-terminated poly(dimethyl / methylhydrogen)siloxane, ii) bis-dimethylhydrogensiloxy-terminated polymethylhydrogensiloxane, iii) bis-trimethylsiloxy-terminated poly(dimethyl / methylhydrogen)siloxane, and iv) bis-trimethylsiloxy-terminated polymethylhydrogensiloxane.

[0053] Methods for preparing polyorganohydrogensiloxanes, such as the hydrolysis and condensation of organohydridohalosilanes, are known in the art; see, for example, U.S. Patent No. 3,957,713 to Jeram et al. and U.S. Patent No. 4,329,273 to Hardman et al. Polyorganohydrogensiloxanes can also be prepared as described, for example, in U.S. Patent No. 2,823,218 to Speier et al., which discloses organohydrogensiloxane oligomers and linear polymers such as 1,1,1,3,3-pentamethyldisiloxane, bis-trimethylsiloxy-terminated polymethylhydrogensiloxane homopolymer, bis-trimethylsiloxy-terminated poly(dimethyl / methylhydrogen)siloxane copolymer, and cyclic polymethylhydrogensiloxane. Polyorganohydrogensiloxanes are also commercially available, such as those available from Gelest, Inc. (Morrisville, Pennsylvania, USA), including, for example, HMS-H271, HMS-071, HMS-993, HMS-301, HMS-301R, HMS-031, HMS-991, HMS-992, HMS-993, HMS-082, HMS-151, HMS-013, HMS-053, HAM-301, HPM-502, and HMS-HM271.

[0054] Typically, the amount of polyorganohydrogensiloxane in the curable composition may be 0.1 wt.% or more, can be 0.25 wt.% or more, can be 0.3 wt.% or more, or even 0.4 wt.% or more, based on the combined weight of components (A), (B), (C), (D), and (E), while generally being 10.0 wt.% or less, can be 5 wt.% or less, 4.8 wt.% or less, 4.5 wt.% or less, 4.2 wt.% or less, 4.1 wt.% or less, 4.04 wt.% or less, or even 1 wt.% or less.

[0055] The ratio of silicon-bonded hydrogen to alkenyl groups in a curable composition is important when relying on a hydrosilylation cure process. Generally, this is determined by calculating the total weight percent of alkenyl groups in the composition, e.g., vinyl [V], and the total weight percent of silicon-bonded hydrogen [H] in the composition, where the molecular weight of hydrogen is 1 and the molecular weight of vinyl is 27, resulting in a molar ratio of silicon-bonded hydrogen to vinyl of 27 [H] / [V]. The aliphatically unsaturated polydiorganosiloxane component and the polyorganohydrogensiloxane (C) may be present in the curable composition in an amount sufficient to provide a molar ratio of silicon-bonded hydrogen atoms to alkenyl groups in the curable composition of 5 or more, 5.1 or more, 5.5 or more, 5.8 or more, 6.1 or more, 6.5 or more, 6.8 or more, 9 or more, 10 or more, 11 or more, 12 or more, 13 or more, or even 14 or more, but at the same time generally 50 or less, 35.2 or less, 35 or less, 34 or less, 30 or less, 25 or less, 22.5 or less, 22 or less, 15 or less, or even 14.9 or less, desirably 10 to 30.

[0056] The components in the curable compositions of the present invention are present in amounts that provide the curable composition with an alkenyl group (e.g., vinyl group) content of 0.017 wt.% or more, and can be 0.020 wt.% or more, 0.022 wt.% or more, but generally 0.089 wt.% or less, 0.085 wt.% or less, 0.08 wt.% or less, 0.075 wt.% or less, 0.07 wt.% or less, 0.06 wt.% or less, 0.05 wt.% or less, 0.045 wt.% or less, 0.041 wt.% or less, 0.03 wt.% or less, or even 0.022 wt.% or less, desirably 0.03 wt.% to 0.08 wt.% based on the combined weight of components (A), (B), (C), (D), and (E). The alkenyl group content (e.g., vinyl content) can be 29 It can be determined by Si NMR.

[0057] The curable composition of the present invention also includes (D) a hydrosilylation catalyst (component (D)). Hydrosilylation catalysts are known in the art and commercially available. Examples of hydrosilylation catalysts include platinum group metal catalysts. Such hydrosilylation catalysts can be (D-1) a metal selected from platinum, rhodium, ruthenium, palladium, osmium, and iridium; alternatively, platinum, ruthenium, and iridium, preferably the metal is platinum. Alternatively, the hydrosilylation catalyst may be (D-2) a compound of such a metal, for example, chloridetris(triphenylphosphane)rhodium(I) (Wilkinson's catalyst), a rhodium diphosphine chelate such as [1,2-bis(diphenylphosphino)ethane]dichlorodirhodium or [1,2-bis(diethylphospino)ethane]dichlorodirhodium, chloroplatinic acid (Speier's catalyst), chloroplatinic acid hexahydrate, or platinum dichloride. Alternatively, the hydrosilylation catalyst may be (D-3) a complex of a platinum group metal compound with an alkenyl-functional organopolysiloxane oligomer, or (D-4) a platinum group metal compound microencapsulated in a matrix or core-shell structure. Complexes of platinum with alkenyl-functional organopolysiloxane oligomers include platinum complexes of 1,3-diethenyl-1,1,3,3-tetramethyldisiloxane (Karstedt's catalyst). Alternatively, the hydrosilylation catalyst may comprise a complex microencapsulated in a (D-5) resin matrix.Exemplary hydrosilylation reaction catalysts are disclosed in U.S. Pat. Nos. 2,823,218 to Speier, 3,159,601 to Ashby, 3,220,972 to Lamoreaux, 3,296,291 to Chalk et al., 3,419,593 to Willing, 3,516,946 to Modic, 3,715,334 to Karstedt, and 3,814,596 to Karstedt. ,730 to Chandra, 3,928,629 to Lee et al., 3,989,668 to Lee et al., 4,766,176 to Lee et al., 4,784,879 to Lee et al., 5,017,654 to Togashi, 5,036,117 to Chung et al., and 5,175,325 to Brown, as well as European Patent No. 0347895(A) to Togashi et al. Hydrosilylation catalysts are commercially available, for example, SYL-OFF™ 4000 Catalyst, SYL-OFF 4500 Catalyst, and SYL-OFF 2700 Catalyst are available from Dow Silicones Corporation (SYL-OFF is a trademark of Dow Silicones Corporation).

[0058] The amount of hydrosilylation catalyst used will depend on various factors, including the selection of the polyorganohydrogensiloxane and aliphatically unsaturated polydiorganosiloxane components and their respective contents of silicon-bonded hydrogen atoms (SiH) and aliphatically unsaturated groups, as well as the platinum group metal content in the selected catalyst; for example, the amount of hydrosilylation catalyst will be sufficient to catalyze the hydrosilylation reaction of the SiH and aliphatically unsaturated groups; alternatively, the amount of catalyst will be sufficient to provide 1 parts per million (ppm) or more of platinum group metal, based on the combined weight of components (A), (B), (C), (D), and (E), and can be 5 ppm or more, 10 ppm or more, 20 ppm or more, or even 30 ppm or more, while generally being 1,000 ppm or less, 500 ppm or less, 300 ppm or less, 130 ppm or less, or even 100 ppm or less. Alternatively, when the hydrosilylation catalyst comprises a platinum-organosiloxane complex, the amount of hydrosilylation catalyst can be 0.01% to 5% by weight, 0.1% to 4.0% by weight, 0.3% to 3.0% by weight, or 0.4% to 2.0% by weight, based on the combined weight of components (A), (B), (C), (D), and (E).

[0059] The curable compositions of the present invention may or may not include (E) a condensation reaction catalyst (component (E)). Condensation reaction catalysts are known in the art and commercially available, such as those described in U.S. Patent Application Publication No. 20210277187(A1). Specific examples of suitable condensation reaction catalysts include benzoic acid, acetic acid, propionic acid, citric acid, or mixtures thereof. The condensation reaction catalyst is present in an amount sufficient to catalyze the condensation reaction of the hydroxyl groups in the hydroxyl-terminated polydiorganosiloxane gum and the uncapped MQ resin; for example, the condensation reaction catalyst may be present at a concentration of 0.001% by weight or greater, and can be 0.01% by weight or greater, 0.03% by weight or greater, 0.05% by weight or greater, 0.08% by weight or greater, 0.09% by weight or greater, or even 0.10% by weight or greater, based on the combined weight of components (A), (B), (C), (D), and (E), while generally being 0.5% by weight or less, 0.25% by weight or less, 0.20% by weight or less, 0.15% by weight or less, 0.13% by weight or less, 0.12% by weight or less, or even 0.11% by weight or less.

[0060] Desirably, the curable compositions of the present invention comprise 5% to 16% by weight of aliphatically unsaturated polydiorganosiloxane polymer (A1) and 20% to 30% by weight of hydroxyl-terminated polydiorganosiloxane gum (A3), based on the combined weight of components (A), (B), (C), (D), and (E), wherein the content of vinyl groups in the curable composition (the "Vi content") is 0.03% to 0.08% by weight, the (B2):(B1) ratio is 0.55 to 5, and the molar ratio of silicon-bonded hydrogen atoms to vinyl groups is 10 to 30; more desirably, the (A3):(A1) ratio is 1 to 5, and / or the R / P ratio is 1.2 to 1.5.

[0061] The curable compositions of the present invention may or may not contain (F) a hydrosilylation reaction inhibitor (component (F)), which is useful for altering the rate of the hydrosilylation reaction compared to the reaction rate of the same composition but omitting the inhibitor. Examples of suitable inhibitors include acetylenic alcohols such as 2-methyl-3-butyn-2-ol, dimethylhexynol, 3,5-dimethyl-1-hexyn-3-ol, 1-butyn-3-ol, 1-propyn-3-ol, 2-methyl-3-butyn-2-ol, 3-methyl-1-butyn-3-ol, 3-methyl-1-pentyn-3-ol, 3-phenyl-1-butyn-3-ol, 4-ethyl-1-octyn-3-ol, 3,5-dimethyl-1-hexyn-3-ol, and 1-ethynyl-1-cyclohexanol (ETCH); silylated acetylenic alcohols such as those prepared by methods known in the art (e.g., U.S. Pat. No. 6,677,407 to Bilgrien et al. discloses silylation of the above acetylenic alcohols by reaction with chlorosilanes in the presence of an acid acceptor); cycloalkenylsiloxanes such as methyl Examples of suitable inhibitors include vinylcyclosiloxanes such as 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane and 1,3,5,7-tetramethyl-1,3,5,7-tetrahexenylcyclotetrasiloxane; eneyne compounds such as 3-methyl-3-penten-1-yne and 3,5-dimethyl-3-hexen-1-yne; triazoles such as benzotriazole; phosphines; mercaptans; hydrazines; amines such as tetramethylethylenediamine, 3-dimethylamino-1-propyne, n-methylpropargylamine, propargylamine, and 1-ethynylcyclohexylamine; fumarates including dialkyl fumarates such as diethyl fumarate, dialkenyl fumarates such as diallyl fumarate, and dialkoxyalkyl fumarates; maleates such as diallyl maleate and diethyl maleate; nitriles; ethers; or mixtures thereof. Desirably, the inhibitor is ETCH.The inhibitor may be present in a concentration of zero or greater, and can be greater than zero, 0.001% or greater, 0.01% or greater, 0.02% or greater, 0.04% or greater, 0.05% or greater, or even 0.1% or greater by weight, based on the combined weight of components (A), (B), (C), (D), and (E), while generally not greater than 5% by weight, and can be not greater than 1%, not greater than 0.5%, not greater than 0.3%, or even not greater than 0.25% by weight, and can be between 0.001% and 5% by weight.

[0062] The curable compositions of the present invention may or may not include (G) an anchorage additive (component (G)). Suitable adhesion promoters for component (G) may include silane coupling agents such as methyltrimethoxysilane, vinyltrimethoxysilane, allyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, bis(trimethoxysilyl)propane, and bis(trimethoxysilylhexane); and mixtures or reaction mixtures of such silane coupling agents. Alternatively, the adhesion promoter may be tetramethoxysilane, tetraethoxysilane, dimethyldimethoxysilane, methylphenyldimethoxysilane, methylphenyldiethoxysilane, phenyltrimethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, vinyltriethoxysilane, allyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, or 3-methacryloxypropyltrimethoxysilane.

[0063] Other suitable adhesion promoters are exemplified by the reaction product of a vinylalkoxysilane with an epoxy-functional alkoxysilane; the reaction product of a vinylalkoxysilane with an epoxy-functional alkoxysilane; and a combination (e.g., physical blend and / or reaction product) of a polyorganosiloxane having at least one aliphatically unsaturated hydrocarbon group and at least one hydrolyzable group per molecule with an epoxy-functional alkoxysilane (e.g., a combination of a hydroxy-terminated vinyl-functional polydimethylsiloxane with glycidoxypropyltrimethoxysilane).

[0064] Exemplary fixing additives are known in the art and are disclosed, for example, in U.S. Pat. No. 9,562,149, U.S. Patent Application Publication No. 2003 / 0088042, U.S. Patent Application Publication No. 2004 / 0254274, U.S. Patent Application Publication No. 2005 / 0038188, U.S. Patent Application Publication No. 2012 / 0328863, paragraph

[0091] , and U.S. Patent Application Publication No. 2017 / 0233612, paragraph

[0041] , and European Patent No. 0 556 023. Fixing additives are commercially available. For example, SYL-OFF™ 9250, SYL-OFF 9176, SYL-OFF 297, and SYL-OFF 397 are available from Dow Silicones Corporation (Midland, Michigan, USA). Other exemplary adhesion promoters include (G-1) vinyltriacetoxysilane, (G-2) glycidoxypropyltrimethoxysilane, and (G-3) a combination of (G-1) and (G-2), which combination (G-3) may be a mixture and / or a reaction product.

[0065] The amount of the adhesion promoter depends on various factors, including the type of substrate to which the curable composition is applied. For example, adhesion promoter (G) may be present in a concentration of 0 or more, and can be 0.01% by weight or more, 0.1% by weight or more, 0.5% by weight or more, or even 0.6% by weight or more, based on the total weight of components (A), (B), (C), (D), and (E), but generally 5% by weight or less, and can be 4% by weight or less, 3% by weight or less, 2% by weight or less, 1.5% by weight or less, or even 1% by weight or less, and can be 0.01% by weight to 5% by weight.

[0066] The curable composition may or may not contain (H) an olefin reactive diluent (component (H)). The olefin reactive diluent (also "reactive diluent") contains a hydrocarbon compound having 8 to 18 carbon atoms and at least one aliphatic unsaturation per molecule. The olefin reactive diluent may be linear. The reactive diluent may contain 12 to 16 carbon atoms, or 14 to 16 carbon atoms. The reactive diluent may be linear or branched. The aliphatic unsaturation may be pendant or terminal. Suitable reactive diluents for component (H) may be any one or any combination of two or more of the following: (H-1) n-dodecene; (H-2) n-tetradecene; (H-3) n-hexadecene; (H-4) n-octadecene; (H-5) any branched isomer of (H-1), (H-2), (H-3), and / or (H-4); and (H-6) a combination of two or more of (H-1), (H-2), (H-3), (H-4), and / or (H-5). The reactive diluent may have a double bond at a terminal position. Desirably, the reactive diluent is selected from n-tetradecene, n-hexadecene, or a mixture thereof. The amount of olefin reactive diluent can be zero or greater, greater than zero, 0.5% or greater, 0.7% or greater, 1% or greater, 1.2% or greater, 1.5% or greater, 1.75% or greater, or even 1.9% or greater, based on the combined weight of components (A), (B), (C), (D), and (E), while generally being less than 10% and can be 8% or less, 6% or less, 4% or less, 2% or less, or even 1.8% or less.

[0067] The curable composition may or may not contain (I) a solvent (component (I)). The solvent may be an organic solvent such as a hydrocarbon, a ketone, an acetate, an ether, and / or a cyclic siloxane having an average degree of polymerization of 3 to 10. Hydrocarbons suitable for the solvent may be aromatic hydrocarbons such as benzene, toluene, or xylene; aliphatic hydrocarbons such as hexane, heptane, octane, or isoparaffin; or a combination thereof. Desirably, the solvent may be a glycol ether such as propylene glycol methyl ether, dipropylene glycol methyl ether, or propylene glycol n-butyl ether. Suitable ketones include acetone, methyl ethyl ketone, or methyl isobutyl ketone. Suitable acetates include ethyl acetate or isobutyl acetate. Suitable ethers include diisopropyl ether or 1,4-dioxane. Suitable cyclic siloxanes having a degree of polymerization of 3 to 10, alternatively 3 to 6, include hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, and / or decamethylcyclopentasiloxane. Desirably, the solvent may be selected from benzene, toluene, xylene, heptane, ethylbenzene, ethyl acetate, or a combination of two or more thereof.

[0068] The amount of solvent depends on various factors, such as the type of solvent selected and the amount and type of other components selected for the curable composition. However, the amount of solvent may range from 0 to 90%, such as 0 to 70%, 20 to 70%, or 30 to 70%, based on the total weight of all components in the curable composition. Solvents can be added during the preparation of the curable composition, for example, to aid in the mixing and delivery of one or more of the above components. All or a portion of the solvent may be added along with one or more of the other components. For example, the polyorganosilicate resin may be dissolved in a solvent before being combined with the other components in the curable composition. After the curable composition is prepared, all or a portion of the solvent may optionally be removed so that the resulting curable composition is solvent-free, i.e., does not contain solvent, or may contain trace amounts of residual solvent from the delivery of the above components in the curable composition.

[0069] The curable compositions of the present invention may or may not include a (J) neutralizing agent (component (J)), which can be useful in accelerating the condensation reaction. Suitable neutralizing agents may include silyl phosphonates, silyl phosphates, or mixtures thereof. An exemplary neutralizing agent is a bis(trimethylsilyl)phosphonate, such as bis(trimethylsilyl)vinylphosphonate, bis(trimethylsilyl)phosphate, or a mixture thereof. The concentration of the neutralizing agent may be zero or greater, greater than zero, 0.001% to 0.020% by weight, 0.005% to 0.019% by weight, 0.01% to 0.018% by weight, or 0.012% to 0.017% by weight, based on the total weight of components (A), (B), (C), (D), and (E).

[0070] The present invention also relates to a process for preparing the above-mentioned curable composition. The process may include the following steps: step i) mixing a hydroxyl-terminated polydiorganosiloxane gum (A3), an uncapped resin (B2), and a condensation reaction catalyst (E) to form a mixture, i.e., a condensation-curable formulation; and step ii) further mixing the resulting mixture obtained from step i) with an aliphatically unsaturated polydiorganosiloxane polymer (A1), a capped resin (B1), an SiH crosslinker (C), and a hydrosilylation reaction catalyst (D). Optional ingredients, such as a hydrosilylation reaction inhibitor (F), an adhesion promoter (G), an olefin-reactive diluent (H), a solvent (I), and / or a neutralizing agent (J), may be added in step i), step ii), or both steps i) and ii).

[0071] In step i) of the process, optional ingredients such as solvent (I) and, if present, neutralizing agent (J) may be added, typically before adding condensation reaction catalyst (E). For example, step i) for preparing a condensation-curable formulation can be carried out by blending at room temperature or at an elevated temperature, such as in the range of 125-155°C, for example, by mixing the hydroxyl-terminated polydiorganosiloxane gum (A3) and uncapped resin (B2), and optionally, solvent (I) and / or neutralizing agent (J), followed by adding the condensation reaction catalyst (E), and then heating at a temperature such that the condensation reaction partially occurs, for example, in the range of 125-155°C or 145-155°C, for 30 seconds to 30 hours. Alternatively, step i) can be carried out by a low-temperature blending process, including mixing the hydroxyl-terminated polydiorganosiloxane gum (A3), uncapped resin (B2), and optionally, solvent at room temperature, followed by adding the condensation reaction catalyst.

[0072] After completion of step i), the remaining components of the curable composition (i.e., the hydrosilylation-curable formulation), including the aliphatically unsaturated polydiorganosiloxane polymer (A1), the capped resin (B1), the SiH crosslinker (C), and the hydrosilylation reaction catalyst (D), are further mixed with the mixture from step i) to form the curable composition of the present invention. Desirably, in step ii), the aliphatically unsaturated polydiorganosiloxane polymer (A1) and the capped resin (B1) are first mixed with the mixture from step i), followed by the addition of the SiH crosslinker (C) and then the hydrosilylation reaction catalyst (D). Other optional ingredients, such as inhibitors, adhesion promoters, olefin-reactive diluents, and solvents, can be added desirably before adding the SiH crosslinker. Inhibitors may be added before the hydrosilylation reaction catalyst. Mixing in steps i) and ii) of the process for preparing the curable composition can be carried out by conventional means at room temperature for a time sufficient to achieve homogeneity.

[0073] The above-described curable compositions or curable compositions prepared from the above-described processes are suitable for use in forming silicone pressure-sensitive adhesives comprising the cured product of the curable composition, i.e., pressure-sensitive adhesives formed by curing the curable composition via simultaneous hydrosilylation and condensation reactions. The curable compositions of the present invention are hydrosilylation and condensation reaction curable compositions.

[0074] The present invention also relates to an adhesive article comprising a silicone pressure-sensitive adhesive present on at least one surface of a substrate. The adhesive article can be prepared by a process comprising: (i) applying a curable composition to at least one surface of the substrate; and (ii) curing the curable composition to form a silicone pressure-sensitive adhesive (also known as a "cured PSA") on the surface of the substrate, thereby forming an adhesive article. The curable composition can be applied to both sides of the substrate. Application of the curable composition to the substrate can be carried out by any convenient means, such as a gravure coater, comma coater, offset coater, offset gravure coater, roller coater, reverse roller coater, air knife coater, slot die, or curtain coater. The substrate can be any material capable of withstanding the curing conditions described below, which are used to cure the curable composition to form a silicone pressure-sensitive adhesive on the substrate. For example, any substrate capable of withstanding heat treatment at temperatures of 120 degrees Celsius (°C) or higher, alternatively 150°C, is suitable. Examples of suitable materials for such substrates include polymer films and / or foams, which may include polyimide (PI), polyetheretherketone (PEEK), polyethylene naphthalate (PEN), liquid crystal polyacrylate, polyamideimide (PAI), polyether sulfide (PES), polyethylene terephthalate (PET), polycarbonate (PC), polymethylmethacrylate (PMMA), thermoplastic polyurethane (TPU), thermoplastic elastomer (TPE), polyethylene (PE), or polypropylene (PP). The thickness of the substrate is not critical, but may be between 5 micrometers (μm) and 300 μm, alternatively between 10 μm and 200 μm.Desirably, the substrate is selected from the group consisting of PET, PE, PU, PI, TPE, and TPU.

[0075] Curing of the curable composition can be carried out by any conventional means, for example, by heating at a temperature dependent on the coating line used, typically in the range of 100-240°C, 110-160°C, or 120-150°C, for a time sufficient to cure the curable composition by simultaneous hydrosilylation and condensation reactions. Desirably, curing can be carried out at 120-160°C, and cure times can be from 1 second to 20 minutes, 2 seconds to 5 minutes, or 5 seconds to 2 minutes. The heating and curing steps can be carried out in an oven, such as an air-circulating oven or tunnel furnace, or by passing the coated film around a heated cylinder.

[0076] To improve the bonding of the silicone pressure-sensitive adhesive to the substrate, the method of making an adhesive article may optionally further comprise treating the substrate before applying the curable composition. Treatment of the substrate can be carried out by any convenient technique, such as applying a primer or subjecting the substrate to a corona discharge treatment, etching, or plasma treatment before applying the curable composition or silicone pressure-sensitive adhesive to the substrate.

[0077] The method for producing an adhesive article can optionally further comprise (iii) applying a low-adhesion silicone protective film ("low-adhesion Si-PF") to the silicone pressure-sensitive adhesive (obtained by curing the above-mentioned curable composition) opposite the substrate, for example, to protect the silicone pressure-sensitive adhesive before using the adhesive article, so that the silicone pressure-sensitive adhesive is between and in contact with the substrate and the low-adhesion silicone pressure-sensitive adhesive ("low-adhesion PSA") of the low-adhesion Si-PF. Low-adhesion Si-PF typically refers to a protective film comprising a second substrate, which can be the same as or different from the above-mentioned substrate, and a low-adhesion Si-PSA other than the above-mentioned silicone pressure-sensitive adhesive of the present invention, and which has an adhesion to stainless steel (SUS) of less than 10 g / in when measured using an AR 1500 adhesion / peel tester according to ASTM D3330. The low-adhesion Si-PF can also be directly laminated onto the silicone pressure-sensitive adhesive of the present invention during the manufacturing process, such as for die-cutting protection or masking protection applications in electronic applications. The low-adhesion Si-PSA in the low-adhesion Si-PF can be prepared by curing (a) a low-adhesion silicone PSA composition, or a mixture of the low-adhesion silicone PSA composition (a) with (b) a medium- to high-adhesion silicone PSA composition, where the resulting low-adhesion PSA has an adhesion to SUS of less than 10 g / in. A "low-adhesion silicone PSA composition" refers to a silicone PSA composition capable of providing a cured product with an adhesion to SUS of less than 10 g / in. A "medium- to high-adhesion silicone PSA composition" refers to a silicone PSA composition capable of providing a cured product with an adhesion to SUS of greater than 10 g / in. Suitable low-adhesion silicone PSA compositions can include, for example, DOWSIL™ 7626 adhesive, DOWSIL 7636 adhesive, DOWSIL 7646 adhesive, DOWSIL 7666 adhesive, DOWSIL 7647 adhesive, DOWSIL 7660 adhesive, DOWSIL 7645 adhesive, DOWSIL 7651 adhesive, or mixtures thereof.Suitable medium to high adhesion silicone PSA compositions may include, for example, DOWSIL 7652 Adhesive, DOWSIL 7667 Adhesive, DOWSIL 7657 Adhesive, DOWSIL 7685 Adhesive, DOWSIL 7663 Adhesive, DOWSIL 7695 Adhesive, DOWSIL 7687 Adhesive, or mixtures thereof. The coating weight of the above low adhesion silicone PSA composition or combinations thereof with one or more of the above medium to high adhesion silicone PSA compositions can be sufficient to provide a thickness of the low adhesion Si-PSA of 1 to 100 μm, 5 to 50 μm, or 9 to 11 μm.

[0078] The coating weight of the curable composition of the present invention can be sufficient to provide a cured PSA (i.e., silicone pressure-sensitive adhesive) thickness of 1-100 μm, 5-50 μm, 10-20 μm, or 14-17 μm. The curable composition of the present invention can provide a silicone pressure-sensitive adhesive with desirable adhesion properties, including adhesion to low-adhesion Si-PF of 400 g / in or greater, or adhesion to SUS of 400 g / in or greater, by peeling the low-adhesion Si-PF at a 180° angle at a speed of 300 millimeters per minute (mm / min) after aging the silicone pressure-sensitive adhesive on the low-adhesion Si-PF for 20 minutes at room temperature or for 3 days at 70°C and 80% relative humidity (RH) (further details are provided under the peel adhesion test below). The high adhesion provides the interface between the silicone pressure-sensitive adhesive and the substrate (adherend) with sufficient strength to resist delamination after manufacturing processes such as masking or protection.

[0079] FIG. 1 shows a partial cross-sectional view of an adhesive article (100). The article (100) comprises a silicone pressure-sensitive adhesive (Si-PSA) (102) having a surface (102a) and an opposing surface (102b). The Si-PSA (102) can be as described above for the silicone pressure-sensitive adhesives of the present invention. The opposing surface (102b) of the silicone pressure-sensitive adhesive (102) adheres to the surface (103a) of a low-adhesion silicone PSA (103) with a peel force of 400 g / in or greater, as measured by the test method described in the Examples below. The Si-PSA (102) can have a thickness of 10 μm to 200 μm. The Si-PSA (102) adheres to a first substrate (101) having a surface (101a) and an opposing surface (101b). The surface (102a) of the Si-PSA (102) is in contact with the opposite surface (101b) of the first substrate (101). The Si-PSA (102) is bonded to a low-adhesion Si-PSA (103) having a surface (103a) and an opposite surface (103b). The low-adhesion Si-PSA (103) may have a thickness of 10 μm to 200 μm. The opposite surface (102b) of the Si-PSA (102) is in contact with the opposite surface (103b) of the low-adhesion Si-PSA (103). The low-adhesion Si-PSA (103) is bonded to a second substrate (104) having a surface (104a) and an opposite surface (104b). The surface (103b) of the low-adhesion Si-PSA (103) is in contact with the opposite surface (104a) of the second substrate (104). The low-adhesion silicone protective film (Si-PF) (200) comprises a low-adhesion Si-PSA (103) and a second substrate (104). The low-adhesion Si-PF (200) may be as described above. The first substrate (101) and the second substrate (104) may be the same as or different from those described above, and each may independently have a thickness of 10 μm to 200 μm. [Example]

[0080] Some embodiments of the present invention will now be described in the following examples. All amounts, ratios, and percentages herein are by weight unless otherwise specified. Table 1 lists materials for use in the sample curable compositions described herein below. Note: "Vi" stands for vinyl, "Me" stands for methyl, and D stands for MeSiO 2 / 2 Represents M OH is the compound of the formula ((HO)MeSiO 1 / 2 ) represents a monofunctional siloxane unit, and M Vi is the formula (Me2ViSiO 1 / 2 ) represents a monofunctional siloxane unit. DOWSIL™, SILASTIC™, and XIAMETER™ are trademarks of Dow Silicones Corporation.

[0081] [Table 1-1]

[0082] [Table 1-2] * The low adhesion Si-PF has an adhesion to SUS of 1 g / in as measured using an AR-1500 adhesion / peel tester according to ASTM D3330.

[0083] The formulations of the curable composition samples are shown in Tables 2 and 3, with the amounts of each component reported in grams (g). The curable compositions were prepared by the following steps.

[0084] Step 1): Preparation of condensation-curable formulations by the "cold blending" or "thickening" process. CE-A, CE-F, IE-7, and IE-8 were prepared by the "thickening" process, while the other CEs and IEs were prepared by the "cold blending" process described below.

[0085] "Thickening" process: (A3) OH gum, (B2) uncapped MQ resin, (I) solvent, and (J) neutralizer were added together to a 500 mL three-neck round-bottom reaction flask at room temperature. The resulting mixture was stirred at 250 revolutions per minute (rpm) for 20 minutes using a stainless steel stirring paddle in the middle neck, followed by the addition of (E) condensation reaction catalyst while stirring. Another neck was connected to a Dean-Stark trap, which was then connected to a condenser with tap water cooling capacity. The final neck contained a thermometer and a nitrogen sweep adapter to close the system. Finally, the three-neck flask with the mixture inside was mounted on a heating mantle with temperature control to reach a reaction temperature of 145 °C. The reaction was continued for 3 hours, starting from the onset of reflux. The resulting formulation was then cooled to room temperature for later use.

[0086] "Cold Blending" Process: (A3) OH Gum, (B2) Uncapped MQ Resin, and (I) Solvent were added together in a 500 mL three-necked round-bottom reaction flask at room temperature and mixed at 3500 rpm for 30 seconds until homogeneous. Then, (E) Condensation Reaction Catalyst was further added and mixed at 3500 rpm for 30 seconds until homogeneous. The resulting formulation was for further use.

[0087] Step 2): (A1) Vi polymer and (B1) capped MQ resin were added to the condensation-curable formulation obtained from step 1) above and mixed until homogeneous. Next, (F) inhibitor, (G) fixative, (H) olefin-reactive diluent, and (I) solvent were further added and mixed until homogeneous. Next, (C) SiH crosslinker was further added and mixed until homogeneous, followed by (D) Pt catalyst, which was also mixed until homogeneous to obtain a curable composition sample. The components in steps i) and ii) were mixed at room temperature for 300 seconds at 500 rpm.

[0088] Each curable composition sample obtained above was applied to a 50 μm thick PET substrate and cured in an oven at 150° C. for 2 minutes, resulting in a silicone pressure-sensitive adhesive (i.e., the cured product of the curable composition) having a thickness of 15.5±1.5 μm. After curing, the resulting tape samples were characterized for adhesive properties according to the peel adhesion test described below. The characterization results are shown in Tables 4 and 5 below.

[0089] [Table 2]

[0090] [Table 3]

[0091] Data analysis and characterization Peel Adhesion Test Peel adhesion testing was performed according to ASTM D3330.

[0092] Each tape sample prepared as described above was tested for adhesion to a substrate. The substrates were SUS and the low-adhesion Si-PF prepared above. The SUS plates were first cleaned with solvent before use. The tape samples obtained above were cut to 1-inch widths and then applied to the substrates using a standard 2 kg test roller, rolling twice in each direction at a speed of 10 millimeters per second (mm / s), so that the silicone pressure-sensitive adhesive was in contact with the substrate. Peel tests were performed using an adhesion / peel tester, model AR-1500, at a peel rate of 300 mm / min and a 180-degree angle. When the low-adhesion Si-PF substrate was subjected to the peel test, the low-adhesion Si-PF peeled from the tape. When the SUS substrate was subjected to the peel test, the tape peeled from the SUS. Units were in grams / in.

[0093] The "Adhesion to SUS (RT-20 min)" test was performed on samples after the silicone pressure sensitive adhesive was in contact with SUS at room temperature (RT, 25°C) for 20 minutes.

[0094] The "Adhesion to Si-PF (RT-20 min)" test was performed on samples after the silicone pressure-sensitive adhesive was in contact with low-adhesion Si-PF for 20 minutes at RT. The "Aged Adhesion to Si-PF (70°C and 80% RH-3d)" test was performed as above after the samples were aged at 70°C and 80% RH for 3 days.

[0095] Of note, some samples were reported as cohesion failures (CF) because the silicone pressure-sensitive adhesive had partially or completely transferred to the adherend, and some samples had adhesion values so low that they could not be detected under the test conditions described above (i.e., 1 g / cm, below the detection limit of the adhesion / peel tester). 2 ), they are reported as "NA."

[0096] Probe Tack Test Probe testing was performed according to ASTM D2979 using a Polyken™ Probe Tack Tester / PT-1000.

[0097] Table 4 contains the characterization results of the IE samples. As shown in Table 4, all IE1-9 curable compositions can be cured to form silicone pressure-sensitive adhesives with desirable adhesive properties, including initial adhesion to low-adhesion Si-PF of 400 g / in or greater at room temperature for 20 minutes, and aged adhesion to Si-PF of 400 g / in or greater after aging for 3 days at 70°C and 80% RH. Additionally, IE1-3, 5, and 7-9 samples also provided adhesion to SUS of 400 g / in or greater.

[0098] Table 5 contains the characterization results of the CE samples. As shown in Table 5, CE-I (no Vi-polymer or Vi-gum), CE-A (Vi-gum instead of Vi-polymer), and CE-C (3.08 wt.% Vi-polymer) all experienced CF during peeling from Si-PF. CE-D, containing 22.1 wt.% Vi-polymer with a 0.74 OH-gum to Vi-polymer weight ratio, achieved adhesion to Si-PF of less than 400 g / in. CE-J, which contained no OH-gum or uncapped MQ resin, showed adhesion to Si-PF of less than 400 g / in. CE-B, which contained no OH-gum, failed to achieve adhesion to Si-PF of 400 g / in or greater. CE-F, which contained less than the claimed amount of uncapped MQ resin, showed undesirably low initial adhesion to Si-PF as a result of an undesirably low amount of uncapped MQ resin and / or a low ratio of 0.51 for uncapped MQ resin / capped MQ resin. CE-E, which did not contain the capped MQ resin, showed poor adhesion to Si-PF. Samples CE-G and CE-H, which had R / P ratios outside the claimed range, showed adhesion to Si-PF of less than 400 g / in and cohesive failure, respectively.

[0099] [Table 4] The weight percent values are based on the total weight of components (A), (B), (C), (D) and (E).

[0100] [Table 5] The weight percent values are based on the total weight of components (A), (B), (C), (D) and (E).

Claims

1. A curable composition comprising: (A) a polydiorganosiloxane component, (A1) greater than 3.1 weight percent to 20 weight percent of an aliphatically unsaturated polydiorganosiloxane polymer of formula (AI), R Ｍ （３－ｃ） R Ｕ ｃ SiO-(R Ｕ R Ｍ SiO) ａ -(R Ｍ ２ SiO) ｂ -SiR Ｕ ｄ R Ｍ （３－ｄ） (A-I) In the formula, each R Ｍ are independently selected from the group consisting of monovalent hydrocarbon groups of 1 to 30 carbon atoms free of aliphatic unsaturation and monovalent halogenated hydrocarbon groups free of aliphatic unsaturation; and each R Ｕ are independently alkenyl groups, and the subscripts a, b, c, and d are a≧0, b>0, c is 0 or 1, and d is 0 or 1, and the amount (a+b) is from 100 to 2000 and has an average value such that the amount (a+c+d)≧2; (A3) A hydroxyl-terminated polydiorganosiloxane gum of the unit formula (A-III): {(HO)R Ｍ ２ Yes １／２ } ２ (R Ｍ ２ Yes ２／２ ) ｅ (A-III) In the formula, each R Ｍ are independently selected from the group consisting of monovalent hydrocarbon radicals of 1 to 30 carbon atoms free of aliphatic unsaturation and monovalent halogenated hydrocarbon radicals free of aliphatic unsaturation, and the subscript e has a value sufficient to impart to said hydroxyl-terminated polydiorganosiloxane gum a plasticity of 20 mils (0.51 mm) to 80 mils (2.03 mm), wherein plasticity is measured according to ASTM D926 by applying a 1 kilogram (kg) load to a spherical sample weighing 4.2 grams (g) for 3 minutes at 25°C, the results being measured in thousandths of an inch (mil), the procedure being ASTM D926. D926, which comprises a polydiorganosiloxane component comprising: a hydroxyl-terminated polydiorganosiloxane gum present in an amount to provide a weight ratio of said hydroxyl-terminated polydiorganosiloxane gum (A3) to said aliphatically unsaturated polydiorganosiloxane polymer (A1) of from 0.89:1 to 9.33:1; (B) a polyorganosilicate resin component, (B1) Unit formula (BI): (R Ｍ ３ SiO １／２ ) ｚ (SiO ４／２ ) ｏ Z ｆ wherein each R Ｍ are independently selected from the group consisting of monovalent hydrocarbon groups of 1 to 30 carbon atoms free of aliphatic unsaturation and monovalent halogenated hydrocarbon groups free of aliphatic unsaturation, each Z is independently a hydrolyzable group, subscript f ranges from 0 to a value sufficient to provide said capped resin with a maximum hydrolyzable group content of 2%, subscripts z and o have values such that o > 1, z > 4, and the amount (o + z) has a value sufficient to provide said capped resin with a number average molecular weight of 500 g / mol to less than 7,000 g / mol; (B2) 18.53 to 54.3 weight percent of a unit of the formula (B-II): (R Ｍ ３ SiO １／２ ) ｚ’ (SiO ４／２ ) ｏ’ Z ｆ’ wherein each R Ｍ are independently selected from the group consisting of monovalent hydrocarbon groups of 1 to 30 carbon atoms free of aliphatic unsaturation and monovalent halogenated hydrocarbon groups free of aliphatic unsaturation, each Z is independently a hydrolyzable group, subscript f' has a value sufficient to provide the uncapped resin with a hydrolyzable group content of greater than 3% to 10%, and subscripts z' and o' have values such that o' > 1, z' > 4, and the amount (o' + z') has a value sufficient to provide said uncapped resin with a number average molecular weight of 500 g / mol to less than 7,000 g / mol; the weight ratio of the uncapped resin (B2) to the capped resin (B1) is greater than 0.51 to 58.82; (A) the polydiorganosiloxane component and (B) the polyorganosilicate resin component, wherein the polyorganosilicate resin component is present in amounts to provide a weight ratio of the polyorganosilicate resin component (B) to the polydiorganosiloxane component (A) of from 1.2:1 to less than 1.62:1; (C) A polyorganohydrogensiloxane having the unit formula (CI): (R Ｍ ３ SiO １／２ ) ｐ (R Ｍ ２ SiO ２／２ ) ｑ (R Ｍ SiO ３／２ ) ｒ (SiO ４／２ ) ｓ (R Ｍ HSiO ２／２ ) ｔ (R Ｍ ２ HSiO １／２ ) ｕ (C-I) In the formula, each R Ｍ are independently selected from the group consisting of monovalent hydrocarbon groups of 1 to 30 carbon atoms free of aliphatic unsaturation and monovalent halogenated hydrocarbon groups free of aliphatic unsaturation, the subscripts p, q, r, s, t, and u having values such that p≧0, q≧0, r≧0, s≧0, t≧0, u≧0, (t+u)≧2, and the amount (p+q+r+s+t+u) is sufficient to provide said polyorganohydrogensiloxane with a degree of polymerization from 5 to 100, which is present in an amount to provide said curable composition with a molar ratio of silicon-bonded hydrogen atoms to alkenyl groups from 5 to 50; (D) a hydrosilylation catalyst in an amount sufficient to provide 1 to 1000 ppm of a platinum group metal; (E) a condensation reaction catalyst, the alkenyl group content of the curable composition being in the range of 0.017 weight percent to 0.089 weight percent; The weight percentages are based on the total weight of components (A), (B), (C), (D), and (E).

2. The curable composition of claim 1, further comprising: (F) 0.001 weight percent to 5 weight percent of a hydrosilylation reaction inhibitor; and (G) 0.01 weight percent to 5 weight percent of an adhesion promoter, or a mixture thereof, wherein the weight percentages are based on the combined weight of components (A), (B), (C), (D), and (E).

3. In formula (AI), each R Ｍ are independently selected from alkyl groups of 1 to 6 carbon atoms, and each R Ｕ is independently selected from the group consisting of vinyl, allyl, and hexenyl, and the amount (a+b) has a value sufficient to impart a viscosity of from 300 mPa*s to 100,000 mPa*s to the aliphatically unsaturated polydiorganosiloxane polymer.

4. In the unit formula (A-III), each R Ｍ 10. The curable composition of claim 1, wherein x is independently an alkyl group of 1 to 6 carbon atoms and subscript e is sufficient to provide said hydroxyl-terminated polydiorganosiloxane gum with a plasticity of 30 mils (0.76 mm) to 70 mils (1.78 mm).

5. In the unit formula (B-II), each R Ｍ are independently an alkyl group of 1 to 6 carbon atoms, each Z is OH, and the amount (z'+o') has a value sufficient to provide the uncapped resin (B2) with a number average molecular weight of 2,900 g / mol to 5,000 g / mol.

6. The curable composition of claim 1, wherein the hydroxyl-terminated polydiorganosiloxane gum (A3) is present in a concentration of 17.67 weight percent to 36.2 weight percent, based on the combined weight of components (A), (B), (C), (D), and (E).

7. The curable composition of claim 1, wherein the polydiorganosiloxane component (A) comprises 5 to 16 weight percent of the aliphatic unsaturated polydiorganosiloxane polymer (A1) and 20 to 30 weight percent of the hydroxyl-terminated polydiorganosiloxane gum (A3), expressed as weight percentages based on the total weight of components (A), (B), (C), (D), and (E); the content of vinyl groups in the curable composition is 0.03 to 0.08 weight percent; the weight ratio of the uncapped resin (B2) to the capped resin (B1) is 0.55 to 5; and the molar ratio of silicon-bonded hydrogen atoms to vinyl groups is 10 to 30.

8. A process for preparing the curable composition of any one of claims 1 to 7, comprising: i) mixing the hydroxyl-terminated polydiorganosiloxane gum (A3), the uncapped resin (B2), and the condensation reaction catalyst (E); ii) further mixing the resulting mixture obtained from step i) with the aliphatically unsaturated polydiorganosiloxane polymer (A1), the capped resin (B1), the polyorganohydrogensiloxane (C), and the hydrosilylation reaction catalyst (D), thereby forming the curable composition.

9. An adhesive article comprising a substrate and a silicone pressure-sensitive adhesive on at least one surface of the substrate, wherein the silicone pressure-sensitive adhesive is a cured product of a curable composition described in any one of claims 1 to 7.

10. A method of making an adhesive article, comprising: Optionally, (1) treating the surface of the substrate; (2) coating the curable composition according to any one of claims 1 to 7 onto at least one surface of the substrate; (3) curing the curable composition.

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