Methods for treating thermoplastic polyurethane covers for golf balls with epoxy compositions
Golf balls having covers made of thermoplastic polyurethane compositions are provided. Multi-piece golf balls can be made. In one embodiment, the outer cover layer is formed from a composition comprising a thermoplastic polyurethane and epoxy compound. Mixtures of multi-functional amines and imines, and multi-functional isocyanates, and epoxy curing agents; and solvent, can be applied to the outer cover. The resulting coating may contain polyurethanes, polyureas, and hybrids, copolymers, and blends thereof. The cover composition and surface coatings can further include catalysts, ultraviolet (UV)-light stabilizers, and other additives. The coating methods have many benefits and the finished balls have good physical properties.
1. A golf ball formed by a method, the method comprising the steps of:
providing a golf ball sub-assembly comprising at least one core layer;
forming an outer cover layer over the sub-assembly, wherein the outer cover layer is formed from a first composition comprising a thermoplastic polyurethane and epoxy-functional compound; and
applying a second composition comprising an epoxy curing agent to the outer cover layer to form at least a partially cross-linked cover for the golf ball.
2. The golf ball of claim 1 , wherein the first composition further comprises a catalyst.
3. The golf ball of claim 2 , wherein the catalyst is selected from the group consisting of dibutyl tin dilaurate, dibutyl tin acetylacetonate, dibutyl tin dibutoxide, dibutyl tin sulfide, dibutyl tin di-2-ethylhexanoate, dibutyl tin (IV) diacetate, dialkyltin (IV) oxide, tributyl tin laurylmercaptate, dibutyl tin dichloride, organo lead, tetrabutyl titanate, tertiary amines, mercaptides, stannous octoate, potassium octoate, zinc octoate, diaz0 compounds, and potassium acetate, and mixtures thereof.