| 摘要 |
PROBLEM TO BE SOLVED: To obtain an elastomer which, when used for a thermal printer head, does not damage a glassy thin film formed thereon by mixing a thermoplastic resin with a crystalline polyhydric alcohol powder as a pore-forming agent and a polyhydric alcohol monomer or polymer as a pore-forming assistant, molding the resultant mixture, and causing the pore-forming agent to be dissolved out into a water-base solvent. SOLUTION: A thermoplastic resin (e.g. PE) is mixed with a crystalline polyhydric alcohol powder (pref. at least one substance selected from among starch, sugar, hemicellulose, and tetramethylolmethane) as a pore-forming agent and a polyhydric alcohol monomer or polymer (e.g. polyethylene glycol or diethylene glycol) as a pore-forming assistant. After the resultant mixture is molded, the pore-forming agent is dissolved out into a water-base solvent (e.g. water). Pref., the resultant elastomer is made so as to have a porosity of 40-80%, a rubber hardness of 20-80 deg., a pore size of 50μm or lower, a density of 0.2-0.6 g/cm<3> , and an m.p. of 60-120 deg.C. |
