Replication processes for producing plastic optical components

Claim 2

A process for producing a plastic optical element having a predetermined surface configuration comprising: a. forming a replica mold having a surface configuration negative to said element's predetermined surface configuration, said negative surface configuration being formed from a polymeric composition which has a flexural modulus above about 2 × 10 5 psi so that the mold will resist distortion of the plastic optical element during cure thereof, said polymeric composition also being one which: (1) is releasable from a master mold surface; (2) has balanced adhesion to said plastic optical element during cure thereof; (3) is resistant to solvent attack by said plastic optical element during cure thereof; (4) is thermally stable at the molding temperature for said plastic optical element; and (5) is capable of forming an optical quality surface on the plastic optical element; b. molding said plastic optical element against said replica mold surface configuration; and, c. releasing said optical element after cure thereof from said replica mold.

Claim 3

A process of claim 1 wherein said polymeric composition is releasable from a glass master mold surface.

Claim 4

A process of claim 2 wherein said plastic optical element comprises an ophthalmic lens.

Claim 5

A process of claim 3 wherein said ophthalmic lens is formed from polymerized allyl diglycol carbonate.

Claim 6

A process of claim 4 wherein the molding of said plastic optical element is conducted at a positive pressure of from about 50 to about 100 psi.

Claim 7

A process of claim 5 wherein the molding of said plastic optical element is conducted at a temperature of from about 40°C. to about 95°C.

Claim 8

A process of claim 6 wherein a flexible member is used to absorb polymerization shrinkage during molding of said plastic replica mold.

Claim 9

A process of claim 7 wherein said polymeric composition comprises a member selected from the group consisting of: a. polymethyl methacrylate cross-linked with a minor amount of a cross-linking agent; b. a copolymer formed from about 99 to about 20 parts of methyl methacrylate and from about 1 to about 80 parts of acrylonitrile, said copolymer being cross-linked with from 0 to a minor amount of a cross-linking agent; c. polystyrene cross-linked with a minor amount of a cross-linking agent; d. a copolymer formed from about 90 to 10 parts of styrene and from about 10 to about 90 parts of acrylonitrile, said copolymer being cross-linked with a minor amount of a cross-linking agent; and, e. a copolymer formed from about 90 to about 10 parts of styrene and from about 10 to about 90 parts of methyl methacrylate, said copolymer being cross-linked with a minor amount of a cross-linking agent.

Claim 10

A process of claim 7 wherein said polymeric composition comprises polystyrene cross-linked with from about 1 to about 20% of a cross-linking agent.

Claim 11

A process of claim 9 wherein said cross-linking agent comprises glycol dimethacrylate.

Claim 12

A process of claim 7 wherein said polymeric composition is a copolymer comprising from about 65 parts to about 25 parts of methyl methacrylate and from about 35 parts to about 75 parts of acrylonitrile, said copolymer being cross-linked with from about 5% to about 30% of a cross-linking agent.

Claim 13

A process of claim 7 wherein said polymeric composition is a copolymer comprising about 30 parts of methyl methacrylate and about 70 parts of acrylonitrile, said copolymer being cross-linked with from about 5 to about 30% of glycol dimethacrylate.

Claim 14

A process for forming a plurality of ophthalmic lenses having a predetermined surface configuration from polymerized allyl diglycol carbonate comprising: a. forming a glass master mold having a surface configuration corresponding to said predetermined surface configuration; b. casting a copolymer comprising from about 65 to about 25 parts of methyl methacrylate and from about 35 to about 75 parts of acrylonitrile, said copolymer being cross-linked with from about 5% to about 30% of a cross-linking agent, against said master mold to form a replica mold having a surface configuration negative to that of said master mold; c. casting allyl diglycol carbonate against said replica mold at a temperature of from about 40°C. to about 95°C. and a pressure of from about 50 to about 100 psi to form an ophthalmic lens; d. releasing said ophthalmic lens from said replica mold; and, e. repeating steps c and d.

Claim 15

A process for forming a plurality of ophthalmic lenses having a predetermined surface configuration from polymerized allyl diglycol carbonate comprising: a. forming a glass master mold having a surface configuration corresponding to said predetermined surface configuration; b. casting a copolymer comprising from about 65 to about 25 parts of methyl methacrylate and from about 35 to about 75 parts of acrylonitrile, said copolymer being cross-linked with from about 5% to about 30% of a cross-linking agent, against said master mold to form a replica mold having a surface configuration negative to that of said master mold; c. casting allyl diglycol carbonate against said replica mold at a temperature of from about 40°C. to about 95°C. and a pressure of from about 50 to about 100 psi to form an ophthalmic lens; d. releasing said ophthalmic lens from said replica mold; and, e. repeating steps c and d.

Claim 16

In a replication process for producing ophthalmic lenses wherein a replica mold is formed by casting a polymeric resin against a glass master and subsequently casting an ophthalmic resin against said replica mold to produce ophthalmic lenses: the improvement comprising selecting a polymeric resin which has a flexural modulus above about 2 × 10 5 psi so that the mold will resist distortion of the ophthalmic lens during cure thereof and which has a composition of: a. polymethyl methacralate cross-linked with from about 5 to about 30% of a cross-linking agent; or, b. a copolymer formed from about 65 to about 25 parts methyl methacralate, from about 35 to about 75 parts acrylonitrile, and from about 5 to about 30% of a cross-linking agent; or, c. polystyrene cross-linked with from about 1 to about 20% of a cross-linking agent; or, d. a copolymer of from about 80 to about 60 parts of styrene, from about 20 to about 40 parts of acrylonitrile, and from about 5 to about 20% of a cross-linking agent; or, e. a copolymer of from about 80 to about 30 parts of styrene, from about 20 to about 70 parts of methyl methacralate and from about 10 to about 20% of a cross-linking agent.

Claim 17

In a replication process for producing ophthalmic lenses wherein a replica mold is formed by casting a polymeric resin against a glass master and subsequently casting an ophthalmic resin against said replica mold to produce ophthalmic lenses: the improvement comprising selecting a polymeric resin which has a flexural modulus above about 2 × 10 5 psi so that the mold will resist distortion of the ophthalmic lens during cure thereof and which has a composition of: a. polymethyl methacralate cross-linked with from about 5 to about 30% of a cross-linking agent; or, b. a copolymer formed from about 65 to about 25 parts methyl methacralate, from about 35 to about 75 parts acrylonitrile, and from about 5 to about 30% of a cross-linking agent; or, c. polystyrene cross-linked with from about 1 to about 20% of a cross-linking agent; or, d. a copolymer of from about 80 to about 60 parts of styrene, from about 20 to about 40 parts of acrylonitrile, and from about 5 to about 20% of a cross-linking agent; or, e. a copolymer of from about 80 to about 30 parts of styrene, from about 20 to about 70 parts of methyl methacralate and from about 10 to about 20% of a cross-linking agent.