| 摘要 |
PROBLEM TO BE SOLVED: To provide a polyamide resin having excellent properties, in particular, high transparency and a production method thereof.SOLUTION: The production method of a polyamide resin comprises a step of causing dicarboxylic acid and diamine to react with each other in a polycondensation manner in the presence of a phosphorus compound of 0.01 to 0.5 mass% with respect to the total amount of the dicarboxylic acid and the diamine thereby obtaining a solid low-order condensate and a step of subjecting the low-order condensate to solid phase polymerization. The dicarboxylic acid contains an aliphatic dicarboxylic acid having 9 to 12 carbon atoms of 70 mol% or more with respect to the total amount of the dicarboxylic acid, the diamine contains diamine represented by the formula (1), where Rrepresents an alkyl group having 1 to 3 carbon atoms, of 50 mol% or more with respect to the total amount of the diamine and the maximum temperature of the polycondensation reaction is in the range of 200 to 230°C and the maximum temperature of the solid phase polymerization is in the range of 170 to 230°C. |
