Patent ID: 7687562

Claim:
A polyamide resin composition comprising m-xylylenediamine (MXDA) as a diamine component and adipic acid (AA) as a dicarboxylic acid component, wherein the polyamide resin composition has: a content of phosphorus atoms (P) and sodium atoms (Na) satisfying the following equations (3) and (4): 30≦P≦190 ppm (3) 3.5≦Na/P (molar ratio)<7.0 (4) and a back pressure increasing coefficient K* satisfying the following equation (1): 0<K*≦14 (1) wherein K* represents a back pressure increasing coefficient expressed by the following equation: K*=[ΔP (MPa)/ T (hr)]/[ Q (kg/hr)/ S (cm 2 )] wherein ΔP (MPa) represents a difference between an initial secondary pressure of a gear pump and a secondary pressure thereof after a lapse of T (hr); T (hr) represents a period of time of filtering the polyamide resin composition with a filter; Q (kg/hr) represents a discharge amount of the polyamide resin composition; S (cm 2 ) represents a filtering area of the filter; and the filter has a filtering diameter of 20 μm.