Abrasion resistant urethane topcoat

A golf ball comprising:

• (a) a core,
• (b) a cover molded onto the core, and
• (c) a topcoat coating over said cover, said topcoat coating being formed from a polyurethane topcoat coating composition which comprises at least:
• (i) a polyol component,
• (ii) an isocyanate component, wherein the equivalent weight ratio of the --NCO in the isocyanate component to the --OH in the polyol component ranges from about 1 to about 2, and
• (iii) a hydroxy functional, polyether-modified polysiloxane copolymer component having a number average molecular weight ranging from about 1,000 to about 10,000.

A golf ball comprising a cover and a core, a topcoat coating formed from a polyurethane topcoat coating composition, and a water-based primer between the cover and the topcoat,

• wherein the polyurethane topcoat coating composition comprises at least three components:
• a polyol component, an isocyanate component, and a hydroxy functional, polyether-modified polysiloxane copolymer component,
• wherein the equivalent weight ratio of the --NCO of the isocyanate component to the --OH of the polyol component ranges from about 1 to about 2, and
• the hydroxy functional, polyether-modified polysiloxane copolymer component has a number average molecular weight ranging from about 1,000 to about 10,000, and
• wherein the water-based primer has a volatile organic content of less than 1.5, and comprises
• an aqueous dispersion of a urethane component, said urethane component having a tensile strength ranging from about 4,000 to about 9,000 p.s.i. and a glass transition temperature ranging from about 20.degree. C. to about 50.degree. C., and being present in primer composition in an amount ranging from 0 to about 90 weight percent, and
• an aqueous dispersion of an acrylic resin component having a glass transition temperature ranging from about 10.degree. C. to about 90.degree. C., and being present in the primer composition in an amount ranging from about 90 to about 10 weight percent,
• wherein each of the aqueous dispersion of the urethane component and the aqueous dispersion of the acrylic resin component contains no more than about 15 weight percent organic solvent.