Glyoxal adhesive system and process for manufacturing same
View Patent ↗An optical adhesive product and a process for manufacturing an optical adhesive product, including laminated film ensembles, and laminated lenses, are described. The optical adhesive product includes a glyoxal water solution that is pH adjusted for use as an optical adhesive that demonstrates a wet peel force strength above about 6 Newtons. A water-based polymer, such as PVOH, may be added to the adhesive system. According to the process, the adhesive system is manufactured and utilized to laminate TAC-PVA-TAC films together to form a polar film ensemble. The polar film ensemble is laminated to an optical substrate and, when forming an ophthalmic lens, surfaced, coated and edged. The optical adhesive product avoids film separation in the polar TAC-PAV-TAC film ensemble during edging.
1. An optical adhesive product for improved wet adhesion in a laminated ophthalmic lens consisting essentially of:
a glyoxal-water solution containing greater than 5% and up to about 50% by weight glyoxal,
less than 1% by weight of a pH adjusting compound to adjust pH of the glyoxal-water solution to below 7, and
water,
wherein the optical adhesive product formed therefrom is an adhesive for the laminated ophthalmic lens, and the adhesive demonstrating a wet peel force strength above about 6 Newtons.
2. The optical adhesive product of claim 1 , wherein the adhesive demonstrates a wet peel force strength between about 8 and about 12 Newtons.
3. The optical adhesive product of claim 1 , wherein said pH adjusting compound comprises hydrochloric acid and the pH is below about 6.
4. The optical adhesive product of claim 1 , wherein the glyoxal in the glyoxal-water solution is in an amount between 30% and 50% by weight.
5. An optical adhesive product comprising:
an acidic glyoxal-water solution containing essentially water and glyoxal, the glyoxal in an amount greater than 5% and up to about 40% by weight, the glyoxal water solution made acidic by having a pH adjusting compound added in an amount less than 1% by weight to adjust the pH to less than 7; and
a water-based polymer in the acidic glyoxal-water solution, the water-based polymer in an amount between 2% and 6% by weight, wherein the water-based polymer comprises polyvinyl alcohol (PVOH);
the optical adhesive product demonstrating a wet peel force strength up to about 18 Newtons.
6. The optical adhesive product of claim 5 , wherein said glyoxal is in an amount greater than 5% and up to 10% by weight and said PVOH is in an amount of between about 3% and 4% by weight, and when formed as the optical adhesive product, the optical adhesive product demonstrates a wet peel force strength between about 10 and about 16 Newtons.
7. The optical adhesive product of claim 5 , wherein the water-based polymer is selected from the group consisting of water-based polymers containing OH groups in the structure, polyurethanes containing hydroxy groups, hydroxyethyl cellulose, hydroxypropyl cellulose, sodium carboxymethyl cellulose, and agarose.