# US 11,993,713 B2 · Polyamide resin composition and method for producing same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,993,713 B2 - Document ID: US11993713B2 - Status: Granted - Kind: B2 - Application number: 17/421,203 - Filed: 2020-01-21 - Published: 2022-03-17 - Granted: 2024-05-28 - Earliest claimed: 2019-01-30 - Assignees: TOYOBO MC Corporation - Applicants: Toyobo Co., Ltd. - Inventors: Nobuhiro Yoshimura; Ryo Umeki - Web page: https://patentgrep.com/patent/US11993713B2 ## CPC - C08L 77/06: Polyamides derived from polyamines and polycarboxylic acids (C08L77/10 takes precedence) - C08K 3/34: Silicon-containing compounds - C08K 7/14: Glass - C08L 77/02: Polyamides derived from omega-amino carboxylic acids or from lactams thereof (C08L77/10 takes precedence) - C08L 2205/025: containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure - C08L 2205/03: containing three or more polymers in a blend - C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06) - C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09) ## Abstract The present invention provides a polyamide resin composition containing (A) a crystalline polyamide resin containing a polycapramide resin as a main component, (B) a semi-aromatic amorphous polyamide resin, and (C) an inorganic reinforcing material, wherein the polyamide resin composition contains, as the (C), (C-1) a glass fiber, (C-2) a wollastonite having a needle shape, and (C-3) an inorganic reinforcing material of a plate-like crystal; a mass ratio of the (B) to (A) satisfies 0.35≤(B)/(A)≤0.80; when a total content of the (A), (B), and (C) is 100 parts by mass, a content (parts) of each component satisfies 30≤(A)+(B)≤55; 10≤(B)≤23; 20≤(C-1)≤40; 8≤(C-2)≤25; 8≤(C-3)≤25; 45≤(C-1)+(C-2)+(C-3)≤70; and an amount of a carboxyl group in the polyamide resin composition is less than 120 meq/kg. The resin composition provides a molded article having excellent strength and rigidity, excellent surface appearance of the molded article, and further excellent weather resistance, even in continuous molding of the composition over a long period of time at a high cylinder temperature. ## Claims ### Claim 1 A polyamide resin composition containing (A) a crystalline polyamide resin containing a polycapramide resin as a main component, (B) a semi-aromatic amorphous polyamide resin, and (C) an inorganic reinforcing material, wherein the polyamide resin composition contains, as the (C) inorganic reinforcing material, (C-1) a glass fiber, (C-2) a wollastonite having a needle shape, and (C-3) an inorganic reinforcing material of a plate-like crystal; a mass ratio of the (B) to (A) satisfies 0.35≤(B)/(A)≤0.80; when a total content of the (A), (B), and (C) is 100 parts by mass, a content of each component satisfies the following relationship, 30 parts by mass≤(A)+(B)≤55 parts by mass 10 parts by mass≤(B)≤23 parts by mass 20 parts by mass≤(C-1)≤40 parts by mass 8 parts by mass≤(C-2)≤25 parts by mass 8 parts by mass≤(C-3)≤25 parts by mass 45 parts by mass≤(C-1)+(C-2)+(C-3)≤70 parts by mass; and an amount of a carboxyl group in the polyamide resin composition is less than 120 meq/kg. ### Claim 2 (depends on 1) The polyamide resin composition according to claim 1, wherein a temperature-decreasing crystallization temperature of the polyamide resin composition as measured by differential scanning calorimetry (DSC) satisfies the following relationship: 180° C.≤(TC2-1)≤185° C. (TC2-1)−(TC2-2)≤5° C. ((TC2-1) represents a temperature-decreasing crystallization temperature of the polyamide resin composition at a retention time of 0 minute, and (TC2-2) represents a temperature-decreasing crystallization temperature of the polyamide resin composition which has been retained at 280° C. for 20 minutes). ### Claim 3 (depends on 1) The polyamide resin composition according to claim 1, further containing (D) a master batch of carbon black and (E) a copper compound, wherein when a total content of the (A), (B), and (C) is 100 parts by mass, a content of the (D) is 1 to 5 parts by mass, and a content of the (E) is 0.001 to 0.1 part by mass. ### Claim 4 (depends on 3) A method for producing the polyamide resin composition according to claim 3, the method including mixing, in advance, the (A) crystalline polyamide resin containing a polycapramide resin as a main component, the (B) semi-aromatic amorphous polyamide resin, the (D) master batch of carbon black, and a dispersion of the (E) copper compound, feeding the mixture to a hopper part of an extruder, and feeding the (C) inorganic reinforcing material by a side feeding method.