Abstract:
Many hard coating materials have been developed and based on the use of metal alkoxide or organosiloxanes prepared via the sol-gel process. Titanium glycolate, zirconium glycolate and silatrane precursors were processed as hard coating materials for polyurethane lens. These precursors are inexpensive and the preparation reaction is simple and straightforward. The effects of the sol-gel process parameters, viz, the type of precursors, the coupling agent (GPTS), and the curing agent (3-APS) were investigated. The surface property evaluation of ophthalmic lens was conducted with respect to the scratch resistance, the adhesion by the tape test, the immersion in boiling water, the refractive index, the %light transmission. The coating solutions were applied onto the polyurethane substrate to achieve the film thickness of ~5.0 m, at the optimized concentration. Silatrane has a good property using the formula of precursor:HCI:IPA:GPTS:%APS(by volume) equal to 0.05g:600 L:1000 L:5%. The same condition was applied for the zirconium glycolate precursor. On the other hand, the titanium glycolate precursor was found to have the optimal formula of 0.05g:600 L:1000 L:600 L:4%. The scratch line results at the coated polyurethane are superior when compared with that of the uncoated polyurethane. When compared with the commercially hard coating lens, the results are nearly the same.
