Isocyanate composition for optical lenses and process for preparing the same
AssigneeSkc Co., Ltd.
InventorsJunghwan Shin, Hyuk Hee Han, Jongmin Shim
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Abstract
An isocyanate composition is prepared from an amine composition, which comprises (a) 99% to less than 100% by weight of m-xylylenediamine; (b) greater than 0% to 0.5% by weight of p-xylylenediamine; and (c) greater than 0% to 0.5% by weight of at least one selected from the group consisting of benzylamine, 4-methylbenzylamine, and 4-cyanobenzylamine. Therefore, the isocyanate composition used in the preparation of a polythiourethane can be controlled to a specific composition in the synthesis thereof, which makes it possible to conveniently produce an optical lens with a high quality.
Claims10
A process for preparing an isocyanate composition, which comprises:
- preparing a first amine composition comprising m-xylylenediamine;
- reducing the content of at least one of p-xylylenediamine, benzylamine, 4-methylbenzylamine, and 4-cyanobenzylamine in the first amine composition to obtain a second amine composition;
- and
- synthesizing an isocyanate from the second amine composition to produce the isocyanate composition,
- wherein the step of synthesizing the isocyanate is carried out by reacting the second amine composition with phosgene, a halo C1-10 alkyl chloroformate, or a halo di-C1-10 alkyl carbonate.
A process for producing an optical lens, which comprises:
- preparing a first amine composition comprising m-xylylenediamine;
- reducing the content of at least one of p-xylylenediamine, benzylamine, 4-methylbenzylamine, and 4-cyanobenzylamine in the first amine composition to obtain a second amine composition;
- synthesizing an isocyanate from the second amine composition to prepare an isocyanate composition;
- and
- mixing the isocyanate composition with a thiol and thermally curing the mixture in a mold,
- wherein the step of synthesizing the isocyanate is carried out by reacting the second amine composition with phosgene, a halo C1-10 alkyl chloroformate, or a halo di-C1-10 alkyl carbonate.
Dependencies are inferred from the claim text.