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Plastic lenses having a high-refractive index, process for the preparation thereof and casting polymerization process for preparing sulfur-containing urethane resin lens and lens prepared thereby

  • US 5,753,730 A
  • Filed: 05/15/1991
  • Issued: 05/19/1998
  • Est. Priority Date: 12/15/1986
  • Status: Expired due to Term
First Claim
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1. A process for preparing a polyurethane lens which comprises:

  • (a) forming a mixture of a polyisocyanate, a polythiol, and an acid phosphoric ester selected from the group consisting of diisopropyl acid phosphate, dibutyl acid phosphate and dioctyl acid phosphate, and(b) subjecting the mixture containing the acid phosphoric ester obtained in step (a) to cast polymerization in a mold for a plastic lens to obtain a polyurethane lens.

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