# US 11,299,622 B2 · Polylactic acid resin composition and polylactic acid resin molded article > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,299,622 B2 - Document ID: US11299622B2 - Status: Granted - Kind: B2 - Application number: 16/003,206 - Filed: 2018-06-08 - Published: 2018-10-11 - Granted: 2022-04-12 - Earliest claimed: 2015-12-08 - Assignees: Bioworks Corporation - Applicants: Bioworks Corporation - Inventors: Takahiko Terada - Web page: https://patentgrep.com/patent/US11299622B2 ## CPC - C08L 67/04: Polyesters derived from hydroxycarboxylic acids, e.g. lactones (C08L67/06 takes precedence) - C08J 3/203: {Solid polymers with solid and/or liquid additives} - C08J 3/226: {using a polymer as a carrier} - C08K 5/20: Carboxylic acid amides - C08L 71/02: Polyalkylene oxides - C08J 2367/04: Polyesters derived from hydroxy carboxylic acids, e.g. lactones (C08J2367/06 takes precedence) - C08J 2467/04: Polyesters derived from hydroxy carboxylic acids, e.g. lactones (C08J2467/06 takes precedence) - C08L 2201/10: Transparent films; Clear coatings; Transparent materials - 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 A polylactic acid resin composition is obtained by melting a mixture containing 100 parts by weight of a poly-L-lactic acid (A) having an L-lactic acid purity of 99 mol % or more, 2.6 to 10 parts by weight of a plasticizer (B), and 0.3 to 1.0 part by weight of a lubricant (C), then cooling the mixture to 20 to 40° C., and then heating the mixture to 46 to 70° C., and satisfies the following conditions (a) and (b): (a) a haze value at a thickness of 0.3 mm is 5% or less; and (b) the degree of crystallinity measured by a differential scanning calorimeter is 50 to 70%. ## Claims ### Claim 1 A polylactic acid resin composition obtained by melting a mixture comprising 100 parts by weight of a poly-L-lactic acid (A) having an L-lactic acid purity of 99 mol % or more, 2.6 to 10 parts by weight of a plasticizer (B), and 0.41 to 1.0 part by weight of a lubricant (C), then cooling the mixture to 20 to 40° C., and then heating the mixture to 46 to 70° C., wherein the plasticizer (B) is at least one selected from the group consisting of polyethylene glycol and a castor oil-based fatty acid ester, or a mixture thereof, the lubricant (C) is at least one selected from the group consisting of ethylene bishydroxystearic acid amide, N-stearyl erucic acid amide, N-stearyl stearic acid amide, and ethylene bisstearic acid amide, or a mixture thereof, and the following conditions (a) and (b) are satisfied: (a) a haze value at a thickness of 0.3 mm is 5% or less; and (b) the degree of crystallinity measured by a differential scanning calorimeter is 50 to 70%, wherein the degree of crystallinity is obtained by measuring crystallization heat quantity (ΔHc) and melting heat quantity (ΔHm) when the polylactic acid resin composition is heated at a rate of 10° C./min using a differential scanning calorimeter (DSC) and performing a calculation according the following formula: degree of crystallinity=(melting heat quantity−crystallization heat quantity)/93×100. ### Claim 2 (depends on 1) The polylactic acid resin composition according to claim 1, wherein a cold crystallization heat generation amount of a poly-L-lactic acid obtained by subjecting the polylactic acid resin composition after cooling and before heating to differential scanning calorimetry at a temperature rising rate of 10° C. per minute is 16 J/g or more. ### Claim 3 (depends on 1) The polylactic acid resin composition according to claim 1, wherein a cold crystallization heat generation amount of a poly-L-lactic acid obtained by subjecting the polylactic acid resin composition after heating to differential scanning calorimetry at a temperature rising rate of 10° C. per minute is 5 J/g or less. ### Claim 4 (depends on 1) The polylactic acid resin composition according to claim 1, wherein the poly-L-lactic acid has a crystal particle diameter of 100 nm or less. ### Claim 5 (depends on 1) The polylactic acid resin composition according to claim 1, wherein the plasticizer (B) has a refractive index of 1.42 to 1.48 at 25° C. ### Claim 6 (depends on 1) The polylactic acid resin composition according to claim 1, further comprising at least one ester selected from the group consisting of a polyglycerol fatty acid ester, a glycerol fatty acid ester, a glycerol diacetomono fatty acid ester, and a sorbitan fatty acid ester, or a mixture thereof. ### Claim 7 (depends on 1) The polylactic acid resin composition according to claim 1, wherein a contact angle of pure water on a surface of the composition measured by a θ/2 method is 60° or less. ### Claim 8 (depends on 1, 130, 160) A polylactic acid resin molded article obtained by further heating the polylactic acid resin composition according to claims 1 to 130 to 160° C. to soften the composition, and then molding and cooling the composition in a die. ### Claim 9 (depends on 8) The polylactic acid resin molded article according to claim 8, wherein the temperature of the die is 30 to 60° C. ### Claim 10 (depends on 1) The polylactic acid resin composition according to claim 1, wherein the degree of crystallinity is a value measured by a differential scanning calorimeter in a sheet having a thickness of 0.3 mm.