| 摘要 |
A poly(arylene sulfide) sheet excellent in planarity and smoothness is formed of a poly(arylene sulfide) having a melt viscosity, eta * of 1,000-25,000 poises as measured at 310 DEG C and a shear rate of 200 sec<-><1>, and a melt crystallization temperature, Tc2 of 170-240 DEG C, wherein Tc2 is an exothermic peak temperature of crystallization which appears upon the measurement by a differential scanning calorimeter at a cooling rate of 10 DEG C/min after the polymer is heated from 23 DEG C to 380 DEG C at a rate of 10 DEG C/min and then held for 3 minutes at 380 DEG C. It has a surface roughness, Ra of 0.09 mu m or less on at least one side thereof and a degree of crystallization of at least 5%. Its number of flexings to break, Y satisfies the following equation (I): log Y >/= 7.11 - 2.34log t (I) wherein t means a thickness ( mu m) of the sheet. The sheet is produced by melt-extruding the poly(arylene sulfide) through a slit die into a sheet-like form and then cooling and crystallizing the sheet on a casting roll. The temperature, T ( DEG C) of the casting roll is controlled to a temperature in a range satisfying the following equation (II): 120 </= T </= 190 - 0.02t (II) wherein t means a thickness ( mu m) of the sheet, thereby conducting the cooling and the crystallization of the sheet at one stage. |
