| 摘要 |
PROBLEM TO BE SOLVED: To facilitate disposal after use by composing a spectacle lens cutting template of aliphatic polyester biodegradable resin. SOLUTION: Out of aliphatic polyester biodegradable resin, polylactic acid resin is excellent in biodegradable properties and corrosion resistance, high in biological stability, transparent with excellent coloring properties and low in cost, and lactic acid which is decomposed substance can be absorbed in an organism. It is preferable that the polylactic acid resin has weight average molecular weight of about 150,000-250,000. In the case of weight average molecular weight being less than about 100,000, strength as a template tends to be slightly inferior, and in the case of exceeding about 300,000, moldability tends to be low. Polylactic acid resin can be a lactic polymer copolymerizing other components copolymerizable with lactic acid monomer or lactide. As the other components, there are dicarboxylic acid, polyhydric alcohol hydroxycarboxylic acid and lactone with two or more ester bond forming functional groups.
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