# US 7,608,656 B2 · Emulsion pressure-sensitive adhesive and process for producing the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,608,656 B2 - Document ID: US7608656B2 - Status: Granted - Kind: B2 - Application number: 12/028,984 - Filed: 2008-02-11 - Published: 2008-06-19 - Granted: 2009-10-27 - Earliest claimed: 2003-02-28 - Assignees: Soken Chemical & Engineering Co., Ltd. - Inventors: Kiyokuni Saitama - Web page: https://patentgrep.com/patent/US7608656B2 ## CPC - C09J 133/14: of esters containing halogen, nitrogen, sulfur or oxygen atoms in addition to the carboxy oxygen - C08F 220/1808: {C8-(meth)acrylate, e.g. isooctyl (meth)acrylate or 2-ethylhexyl (meth)acrylate} - C09J 133/02: Homopolymers or copolymers of acids; Metal or ammonium salts thereof - C09J 133/20: Homopolymers or copolymers of acrylonitrile (C09J155/02 takes precedence) - C09J 151/003: {grafted on to macromolecular compounds obtained by reactions only involving unsaturated carbon-to-carbon bonds (C09J151/04, C09J151/06 take precedence)} - C09J: ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES (preparation of glue or gelatine C09H) - C08F: MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS ## Abstract A process for producing an emulsion pressure-sensitive adhesive includes (co)polymerizing a main monomer in the presence of a protective colloid, the protective colloid being an acrylic copolymer including (A-1) at least one hydrophilic monomer selected from the group consisting of acrylamide, methacrylamide, hydroxyethyl acrylate and hydroxyethyl methacrylate and (B-1) an alkyl (meth)acrylate that is copolymerizable with the hydrophilic monomer (A-1) and whose alkyl group has 4 to 18 carbon atoms, or (A-2) a hydrophilic monomer being acrylic acid and/or methacrylic acid and (B-2) an alkyl (meth)acrylate that is copolymerizable with the hydrophilic monomer (A-2) and whose alkyl group has 4 to 9 carbon atoms; the hydrophilic monomer and the alkyl (meth)acrylate being copolymerized in a weight ratio in the range of 40-70:60-30; the acrylic copolymer having a weight-average molecular weight in the range of 500 to 50000. ## Claims ### Claim 1 A process for producing an emulsion pressure-sensitive adhesive, which process comprises (co)polymerizing a monomer having a polymerizable unsaturated bond based on alkyl acrylates as a main component in an aqueous medium containing a surface active agent in the presence of a protective colloid, the protective colloid being an acrylic copolymer consisting essentially of: (A-1) at least one hydrophilic monomer selected from the group consisting of acrylamide, methacrylamide, hydroxyethyl acrylate and hydroxyethyl methacrylate; (B-1) an alkyl (meth)acrylate that is copolymerizable with the hydrophilic monomer (A-1) and whose alkyl group has 4 to 18 carbon atoms; and (C) a third monomer being acrylonitrile and/or styrene; the hydrophilic monomer, the alkyl (meth)acrylate and the third monomer being copolymerized in a weight ratio (A-1):[(B-1)+(C)] in the range of 40-70:60-30 and in a weight ratio (B-1):(C) in the range of 99.9-20:0.1-80; the acrylic copolymer having a weight-average molecular weight in the range of 500 to 50000. ### Claim 2 A process for producing an emulsion pressure-sensitive adhesive, which process comprises (co)polymerizing a monomer having a polymerizable unsaturated bond based on alkyl acrylates as a main component in an aqueous medium containing a surface active agent in the presence of a protective colloid, the protective colloid being an acrylic copolymer consisting of: (A-2) a hydrophilic monomer being acrylic acid and/or methacrylic acid; and (B-2) an alkyl (meth)acrylate that is copolymerizable with the hydrophilic monomer (A-2) and whose alkyl group has 4 to 9 carbon atoms; the hydrophilic monomer and the alkyl (meth)acrylate being copolymerized in a weight ratio in the range of 40-70:60-30; the acrylic copolymer having a weight-average molecular weight in the range of 500 to 50000. ### Claim 3 A process for producing an emulsion pressure-sensitive adhesive, which process comprises (co)polymerizing a monomer having a polymerizable unsaturated bond based on alkyl acrylates as a main component in an aqueous medium containing a surface active agent in the presence of a protective colloid, the protective colloid being an acrylic copolymer consisting of: (A-2) a hydrophilic monomer being acrylic acid and/or methacrylic acid; (B-2) an alkyl (meth)acrylate that is copolymerizable with the hydrophilic monomer (A-2) and whose alkyl group has 4 to 9 carbon atoms; and (C) a third monomer being acrylonitrile and/or styrene; the hydrophilic monomer, the alkyl (meth)acrylate and the third monomer being copolymerized in a weight ratio (A-2):[(B-2)+(C)] in the range of 40-70:60-30 and in a weight ratio (B-2):(C) in the range of 99.9-20:0.1-80; the acrylic copolymer having a weight-average molecular weight in the range of 500 to 50000. ### Claim 4 An emulsion pressure-sensitive adhesive comprising an aqueous medium and a (co)polymer dispersed in the aqueous medium, the (co)polymer being obtained by (co)polymerizing a monomer having a polymerizable unsaturated bond based on alkyl acrylates as a main component in an aqueous medium containing a surface active agent in the presence of a protective colloid, the protective colloid being an acrylic copolymer consisting essentially of: (A-1) at least one hydrophilic monomer selected from the group consisting of acrylamide, methacrylamide, hydroxyethyl acrylate and hydroxyethyl methacrylate; (B-1) an alkyl (meth)acrylate that is copolymerizable with the hydrophilic monomer (A-1) and whose alkyl group has 4 to 18 carbon atoms; and (C) a third monomer being acrylonitrile and/or styrene; the hydrophilic monomer, the alkyl (meth)acrylate and the third monomer being copolymerized in a weight ratio (A-1):[(B-1)+(C)] in the range of 40-70:60-30 and in a weight ratio (B-1):(C) in the range of 99.9-20:0.1-80; the acrylic copolymer having a weight-average molecular weight in the range of 500 to 50000. ### Claim 5 An emulsion pressure-sensitive adhesive comprising an aqueous medium and a (co)polymer dispersed in the aqueous medium, the (co)polymer being obtained by (co)polymerizing a monomer having a polymerizable unsaturated bond based on alkyl acrylates as a main component in an aqueous medium containing a surface active agent in the presence of a protective colloid, the protective colloid being an acrylic copolymer consisting of: (A-2) a hydrophilic monomer being acrylic acid and/or methacrylic acid; and (B-2) an alkyl (meth)acrylate that is copolymerizable with the hydrophilic monomer (A-2) and whose alkyl group has 4 to 9 carbon atoms; the hydrophilic monomer and the alkyl (meth)acrylate being copolymerized in a weight ratio in the range of 40-70:60-30; the acrylic copolymer having a weight-average molecular weight in the range of 500 to 50000. ### Claim 6 An emulsion pressure-sensitive adhesive comprising an aqueous medium and a (co)polymer dispersed in the aqueous medium, the (co)polymer being obtained by (co)polymerizing a monomer having a polymerizable unsaturated bond based on alkyl acrylates as a main component in an aqueous medium containing a surface active agent in the presence of a protective colloid, the protective colloid being an acrylic copolymer consisting of: (A-2) a hydrophilic monomer being acrylic acid and/or methacrylic acid; (B-2) an alkyl (meth)acrylate that is copolymerizable with the hydrophilic monomer (A-2) and whose alkyl group has 4 to 9 carbon atoms; and (C) a third monomer being acrylonitrile and/or styrene; the hydrophilic monomer, the alkyl (meth)acrylate and the third monomer being copolymerized in a weight ratio (A-2):[(B-2)+(C)] in the range of 40-70:60-30 and in a weight ratio (B-2):(C) in the range of 99.9-20:0.1-80; the acrylic copolymer having a weight-average molecular weight in the range of 500 to 50000. ### Claim 7 (depends on 1) The process for producing an emulsion pressure-sensitive adhesive according to claim 1, wherein (co)polymerization in the presence of the protective colloid produces a pressure-sensitive adhesive having a glass transition temperature (Tg) of not more than 0° C. ### Claim 8 (depends on 2) The process for producing an emulsion pressure-sensitive adhesive according to claim 2, wherein (co)polymerization in the presence of the protective colloid produces a pressure-sensitive adhesive having a glass transition temperature (Tg) of not more than 0° C. ### Claim 9 (depends on 3) The process for producing an emulsion pressure-sensitive adhesive according to claim 3, wherein (co)polymerization in the presence of the protective colloid produces a pressure-sensitive adhesive having a glass transition temperature (Tg) of not more than 0° C. ### Claim 10 (depends on 4) The emulsion pressure-sensitive adhesive according to claim 4, wherein the pressure-sensitive adhesive comprising the (co)polymer has a glass transition temperature (Tg) of not more than 0° C. ### Claim 11 (depends on 5) The emulsion pressure-sensitive adhesive according to claim 5, wherein the pressure-sensitive adhesive comprising the (co)polymer has a glass transition temperature (Tg) of not more than 0° C. ### Claim 12 (depends on 6) The emulsion pressure-sensitive adhesive according to claim 6, wherein the pressure-sensitive adhesive comprising the (co)polymer has a glass transition temperature (Tg) of not more than 0° C.