| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for producing a thermoplastic urethane resin composition for electronic components free of problems generating outgas from electronic components. <P>SOLUTION: The urethane resin composition for electronic components is obtained by reacting a lactone polyol (A), a polyisocyanate (B) and a low molecular weight glycol (C) as a chain extender. The method for producing the urethane resin composition for electronic components is characterized in that: the lactone polyol (A) is obtained by addition-polymerizing a lactone (A-2) with a low molecular weight glycol initiator (A-1) at 150-180°C reaction temperature under the presence of stannous octylate and/or dibutyltindilaurate (A-3) in 0.0001-0.001 wt.% to the raw material, and after reaching the reaction end point, quickly cooling the reactant to 120°C or lower; where the contained total amount of a cyclic lactone oligomer and a lactone monomer is 0.5 wt.% or less. <P>COPYRIGHT: (C)2011,JPO&INPIT |
