Polyurea covers for golf balls based on isocyanate blends

摘要

A golf ball having a cover material made from a polyurea or polyurea/urethane hybrid composition is provided. The polyurea or polyurea/urethane composition is produced by the reaction of an isocyanate blend having an average NCO functionality in the range of 2.05 to 2.35, a polyamine compound, and amine or hydroxyl curing agent. The resulting cover material has many advantages including improved thermal-stability, durability, toughness, and cut/tear-resistance. The preferred isocyanates in the blend include isophorone diisocyanate (“IPDI”); 1,6-hexamethylene diisocyanate (“HDI”); 4,4′-dicyclohexylmethane diisocyanate (“H12 MDI”); 4,4′-diphenylmethane diisocyanate (4,4′-MDI); toluene diisocyanate (“TDI”); and homopolymers and copolymers thereof.

主权项

1. A golf ball, comprising:
a core; an intermediate layer surrounding the core; and a cover layer surrounding the intermediate layer, the cover layer being formed from a polyurea or polyurea/urethane hybrid composition that is produced by the steps of: i) forming an isocyanate blend of hexamethylene diisocyanate (HDI) homopolymer having an average NCO functionality of 2.5, and 4,4′-dicyclohexylmethane diisocyanate (H12MDI), wherein the hexamethylene diisocyanate (HDI) homopolymer having an average NCO functionality of 2.5 is present in the blend in an amount of 30 to 50 weight % and the 4,4′-dicyclohexylmethane diisocyanate (H12MDI) is present in an amount of 70 to 50 weight %, and the blend has an average NCO functionality in the range of 2.05 to 2.35; ii) reacting the isocyanate blend with a polyamine compound and a curing agent selected from the group consisting of amine-terminated curing agents, hydroxyl-terminated curing agents, and mixtures thereof.