US 5,852,112 A · Polyester resin-based high index ophthalmic lenses having improved optical unformity and/or tintability

Abstract

Unsaturated polyester resin-based compositions that are modified for unexpected improvement in uniform, low optical distortion and/or improved tint speed by the addition of one or more additives selected from an allylic ester and/or an acrylic monomer, together with an exotherm depressant, making the modified polyester resin-based composition commercially viable for casting ophthalmic lenses. The additive(s) and exotherm depressant are useful to modify the polyester for sufficient enhancement of optical distortion and/or tint speed such that any unsaturated polyester resin, capable of producing a clear, low color casting, will be improved sufficiently to provide a composition having the required properties for an ophthalmic lens.

Claims21

Dependent claims

A cross-linkable casting composition capable of being cast and cured into a polymeric ophthalmic lens having an index of refraction of at least 1.50 comprising:

an unsaturated polyester resin in an amount of about 35% to about 63% by weight of the composition;
an additive selected from the group consisting of about 1% to about 20% by weight of an allylic ester monomer;
about 1% to about 20% by weight of an acrylate;
and mixtures thereof;
and
an exotherm depressant selected from the group consisting of alpha-methyl styrene;
terpinolene;
gamma-terpinene;
dilauryl thiodipropionate;
4-tert-butylpyrocatechol;
3-methyl catechol;
and mixtures thereof, in an amount of about 0.01% to about 20% for depressing the rate of polymerization of said composition.

9 more elements

Dependencies are inferred from the claim text.

Polyester resin-based high index ophthalmic lenses having improved optical unformity and/or tintability

Life of this patent

Polyester resin-based high index ophthalmic lenses having improved optical unformity and/or tintability

Life of this patent

Abstract

Claims21