The compositions, articles, and methods disclosed herein have applications in fields utilizing self-healing or self-repairing hard coatings, especially transparent hard coatings. This disclosure focuses on applications in the ophthalmic field, however, one skilled in the art will recognize applications in additional areas, such as automotive and window technology. More specifically, this disclosure focuses on compositions of, methods of production for, and ophthalmic articles having clear, scratch-resistant and self-healing coatings.
Self-healing coatings are able to repair themselves, i.e., coatings which would be able, when submitted to a simple physical treatment, to revert completely or partially to an initial non-scratched condition. Examples of such self-healing coatings have been disclosed by Bayer, PPG Industries (Revivance™), Suprapolix BV, and CRG (Veriflex® and also US 2009/062453 and WO 2009/029641). Self-healing coatings are primarily prepared from polyurethanes, epoxies, and shape-memory (co)polymers, which show healing effects after thermal, UV, or humidity treatments. These materials further contain active capsules which can crosslink with other elements once cracks or holes in the coatings appear and open the capsules.
For example, PPG Industries has disclosed coatings which show interesting room-temperature healing effects and even better healing effects upon immersion in warm water. The PPG coatings, marketed as Revivance™ coatings, and the modified coatings are exemplary self-healing coatings. These coatings are primarily prepared from polyurethanes (PU), which show healing effects after thermal or humidity treatments. Self-healing coatings are disclosed in U.S. Pat. No. 7,872,078, and International Patent Application Publication WO2009029641A, which are hereby incorporated herein in their entirety for all purposes.
However, some of these coatings exhibited less than satisfactory results when applied to an ophthalmic lens, such as a polycarbonate (PC) lens. For example, the self-healing coatings were out-performed by previously known hard coating products commercially available at Essilor International, even after a long-term healing process at room temperature. Therefore, there is a need for a composition, and method of making a composition, to improve the scratch-resistance or healing performance of self-healing coatings for ophthalmic uses.