# US 12,006,390 B2 · Latex composition for dip molding, dip-molded product comprising same, and method for manufacturing dip-molded product by using same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,006,390 B2 - Document ID: US12006390B2 - Status: Granted - Kind: B2 - Application number: 17/421,822 - Filed: 2020-08-12 - Published: 2022-03-31 - Granted: 2024-06-11 - Earliest claimed: 2019-10-01 - Assignees: LG Chem, Ltd. - Applicants: LG Chem, Ltd. - Inventors: Won Sang Kwon; Tae Shik Yoon; Jung Su Han; Myung Su Jang - Web page: https://patentgrep.com/patent/US12006390B2 ## CPC - C08F 285/00: Macromolecular compounds obtained by polymerising monomers on to preformed graft polymers - C08L 13/02: Latex - C08F 236/12: with nitriles - C08J 5/02: Direct processing of dispersions, e.g. latex, to articles - C08K 3/06: Sulfur - C08K 3/22: of metals - C08K 5/06: Ethers; Acetals; Ketals; Ortho-esters - C08L 71/02: Polyalkylene oxides - C08F 236/06: Butadiene - C08J 2313/02: Latex - C08J 2371/02: Polyalkylene oxides - C08J 2433/04: esters - C08K 2003/2237: {of titanium} - C08K 2003/2241: {Titanium dioxide} - C08K 2003/2296: {of zinc} - C08F: MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS - C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06) - C08J: WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H (working, e.g. shaping, of plastics B29) - C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09) ## Abstract The present invention relates to a latex composition for dip molding, and such latex composition includes: a carboxylic acid-modified nitrile-based copolymer latex; and a reactive compound having three or more branched chains and a reactive group at a terminal of each of the branched chains, wherein the reactive group is one or more selected from the group consisting of an amine group, a hydroxy group, an epoxy group, a glycidyl group, and an isocyanate group. ## Claims ### Claim 1 A latex composition for dip molding, the latex composition comprising: a carboxylic acid-modified nitrile-based copolymer latex; and a reactive compound having three or more branched chains and a reactive group at a terminal of each of the three or more branched chains, wherein the reactive group is one or more selected from the group consisting of an amine group, a hydroxy group, an epoxy group, a glycidyl group, and an isocyanate group, wherein each of the three or more branched chains included in the reactive compound comprises a repeating unit represented by Formula 1, wherein A is an alkylene group having 2 to 5 carbon atoms, and n is an integer of 150 to 250. ### Claim 2 (depends on 1) The latex composition of claim 1, wherein the reactive compound is represented by the following Formula 2, wherein n is an integer of 150 to 250, and R1 to R4 are each independently one selected from the group consisting of an amine group, a hydroxy group, an epoxy group, a glycidyl group, and an isocyanate group. ### Claim 3 (depends on 2) The latex composition of claim 2, wherein the reactive compound has a weight average molecular weight of 450 to 40,000. ### Claim 4 (depends on 1) The latex composition claim 1, wherein the reactive compound is included in 0.1 parts by weight to 5 parts by weight based on a solid content of 100 parts by weight of the carboxylic acid-modified nitrile-based copolymer latex. ### Claim 5 (depends on 1) The latex composition of claim 1, further comprising a sulfur component, a vulcanization accelerator, and a cross-linking agent, wherein the sulfur component is included in 0.8 parts by weight or less, the vulcanization accelerator is included in 0.6 parts by weight or less, and the cross-linking agent is included in 1.1 parts by weight or less, based on a solid content of 100 parts by weight of the carboxylic acid-modified nitrile-based copolymer latex. ### Claim 6 (depends on 1) The latex composition of claim 1, wherein the carboxylic acid-modified nitrile-based copolymer includes a conjugated diene-based monomer-derived repeating unit, an ethylenically unsaturated nitrile-based monomer-derived repeating unit, and an ethylenically unsaturated acid monomer-derived repeating unit. ### Claim 7 A cross-linked polymer comprising: two or more parts derived from a carboxylic acid-modified nitrile-based copolymer; a part derived from a reactive compound having three or more branched chains and a reactive group at a terminal of each of the three or more branched chains; and a cross-linking part formed by cross-linking a carboxylic acid group included in the carboxylic acid-modified nitrile-based copolymer and the reactive group included in the reactive compound, wherein each of the three or more branched chains included in the reactive compound comprises a repeating unit represented by Formula 1, wherein A is an alkylene group having 2 to 5 carbon atoms, and n is an integer of 150 to 250. ### Claim 8 A method of preparing a latex composition for dip molding, the method comprising: step S10: emulsion-polymerizing a monomer mixture including a conjugated diene-based monomer, an ethylenically unsaturated nitrile-based monomer, and an ethylenically unsaturated acid monomer to obtain a carboxylic acid-modified nitrile-based copolymer latex; and step S20: selectively adding a sulfur component, a vulcanization accelerator, and a cross-linking agent in the presence of the obtained carboxylic acid-modified nitrile-based copolymer latex, wherein a reactive compound having three or more branched chains and a reactive group at a terminal of each of the three or more branched chains is added in the step S10, the step S20, or both the step S10 and the step S20, wherein each of the three or more branched chains included in the reactive compound comprises a repeating unit represented by Formula 1, wherein A is an alkylene group having 2 to 5 carbon atoms, and n is an integer of 150 to 250. ### Claim 9 (depends on 8) The method of claim 8, wherein the reactive compound is added in an amount of 0.1 parts by weight to 5 parts by weight, the sulfur component is added in an amount of 0.8 parts by weight or less, the vulcanization accelerator is added in an amount of 0.6 parts by weight or less, and the cross-linking agent is added in an amount of 1.1 parts by weight or less, based on a solid content of 100 parts by weight of the carboxylic acid-modified nitrile-based copolymer latex. ### Claim 10 (depends on 8) The method of claim 8, wherein the reactive compound added in the step S10 is added to the monomer mixture, to the obtained carboxylic acid-modified nitrile-based copolymer latex, or to both the monomer mixture and the obtained carboxylic acid-modified nitrile-based copolymer latex. ### Claim 11 (depends on 8) The method of claim 8, wherein the cross-linking agent is zinc oxide or titanium oxide. ### Claim 12 (depends on 1) A dip-molded article comprising a layer derived from the latex composition for dip molding of claim 1.