发明名称 |
Oxygen permeable contact lens and method of manufacture therefor. |
摘要 |
<p>An oxygen permeable bifocal contact lens which has a distance vision portion and a near vision portion is made from materials having differing refractive indexes. The near vision portion has a higher refractive index than the distance portion with a Dk of at least 10. The distance portion forms the major portion of the lens and is formed as a crosslinked copolymer with a refractive index of not more than 1.49 from monomeric materials which impart oxygen permeability to the finished lens, and the near vision portion similarly is formed as a crosslinked copolymer from a monomer mixture which includes one or more monomers at a concentration and with a refractive index such that the near vision portion has a refractive index of at least 1.54. The monomer of the near vision portion includes at least one vinyl monomer having a substituted aromatic ring structure to make the monomer bulky and ensure there is only a limited shrinkage on polymerization of such monomers and mixtures containing them. <IMAGE></p> |
申请公布号 |
EP0488627(A2) |
申请公布日期 |
1992.06.03 |
申请号 |
EP19910310842 |
申请日期 |
1991.11.25 |
申请人 |
PILKINGTON VISIONCARE INC. |
发明人 |
PETTIGREW, LISA;RATKOWSKI, DONALD A.;BURKE, WILLIAM E.;WEINSCHENK, JOSEPH I.III |
分类号 |
C08F220/22;B29C39/02;B29D11/00;C08F20/22;C08F26/12;C08F30/08;C08F226/12;C08F230/08;G02B1/04;G02C7/04;G02C7/06 |
主分类号 |
C08F220/22 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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