Custom Monomers and Polymers for Spectacle Lenses
Monomers and polymers used in making spectacle lenses are disclosed. A thermal curing process is disclosed that includes a latent thermal cationic acid generator and optionally a cationic photoinitiator.
1 . A method of making an optical element by forming a polymer layer employing a thermally initiated cationic ring opening polymerization reaction which comprises:
a. mixing one or more monomers and a thermal initiator,
b. forming a layer of the mixture of (a) and
c. heating the layer to cure it.
2 . The method of claim 1 wherein the monomer is an epoxy, an oxetane or mixtures thereof.
3 . The method of claim 1 further comprising adding a photoinitiator to the mixture of (a).
4 . The method of claim 3 wherein the photoinitiator is an arylsulfonium, alkylsulfonium, or aryliodonium photo acid generator.
5 . The method of claim 1 wherein the thermal initiator is a latent thermal cationic acid generator.
6 . The method of claim 5 wherein the latent thermal cationic acid generator is ammonium hexafluoroantimonate.
7 . A method of making an optical element by forming a polymer layer employing a thermally initiated cationic ring opening polymerization reaction which comprises:
a. mixing one or more monomers, a latent thermal cationic acid generator and a cationic photoinitiator;
b. forming a layer of the mixture of (a);
c. heating the layer to partially cure it;
d. irradiating the layer to form a variable index of refraction profile in the layer; and
e. heating the layer to fully cure all of the unreacted monomers.
8 . The method of claim 7 wherein the monomer is an epoxy, an oxetane or mixtures thereof.
9 . The method of claim 7 wherein the photoinitiator is an arylsulfonium, alkylsulfonium, or aryliodonium photo acid generator.
10 . The method of claim 7 wherein the thermal initiator is a latent thermal cationic acid generator.
11 . The method of claim 10 wherein the latent thermal cationic acid generator is ammonium hexafluoroantimonate.
12 . A method of making an optical element having a variable index of refraction profile which comprises:
a. forming a layer comprising a mixture of two or more monomers that have differing initial refractive indices and differing cured refractive indices; and
b. curing specific monomers at specific points across the layer to create a pattern of refractive index that has a Δn of up to 0.30.
13 . The method of claim 12 wherein two or more of the following monomers are present in said mixture of (a):
R(SH) n
R(X) n and
R(Y) n
14 . A method of making a lens material comprising:
a. making a mold of a desired shape,
b. melting a mixture of monomers selected from the group consisting of R(SH) n , R(X) n and R(Y) n and
c. curing the monomers with heat
15 . The method of claim 14 wherein the lens material is a slab (sheet).
16 . The method of claim 14 wherein the lens material is a lens blank.
17 . A formulation to make an optical element which comprises:
a. one or more monomers selected from the group consisting of epoxy monomers, oxetane monomers and mixtures thereof and
b. a thermal initiator.
18 . The formulation of claim 17 further comprising a photoinitiator.
19 . The formulation of claim 18 wherein the thermal initiator is a latent thermal cationic acid generator and the photoinitiator is an arylsulfonium, alkylsulfonium, or aryliodonium photo acid generator.
20 . The formulation of claim 19 wherein the latent thermal cationic acid generator is ammonium hexafluoroantimonate.