Golf ball incorporating ultra violet light resistant and light stable layer(s) and method of making
View Patent ↗A golf ball comprising a layer formed from at least one of a thermoset material or a thermoplastic material throughout; the layer having a treated region and an untreated region; the treated region extending inward from an outer surface of the layer and comprising a UV resistance composition; and the untreated region not comprising the UV resistance composition. For example, the treated region may be infused with the UV resistance composition. The layer may be a cover or even an inner golf ball layer, which can sometimes become exposed during play. The UV resistance composition may be formed from a mixture of an ultraviolet light absorber (UVA) and a solvent, the UVA being selected from benzotriazole type stabilizers, hindered amine type stabilizers, phenolic type stabilizers, triazines, or combinations thereof, and the solvent comprising at least one of acetone, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, or butyl acetate.
1. A method of making a golf ball comprising:
providing a finished golf ball or a golf ball subassembly, having a layer that is formed from a thermoset polyurethane material throughout;
exposing an outer surface of the layer at room temperature to a UV resistance composition that is formed from a mixture of an ultraviolet light absorber (UVA) and a solvent; and
forming a treated region in the layer that is infused with the UV resistance composition and extends inward from the outer surface and an untreated region of the layer that is not infused with the UV resistance composition.
2. The method of making a golf ball of claim 1 , wherein the step of exposing the outer surface to the UV resistance composition comprises submerging the outer surface in a bath of the UV resistance composition for up to about 10 minutes.
3. The method of making a golf ball of claim 2 , further comprising the steps of:
removing the finished golf ball or golf ball subassembly from the bath;
rinsing the outer surface; and
drying the outer surface.
4. The method of making a golf ball of claim 1 , wherein the UVA is selected from benzotriazole type stabilizers, hindered amine type stabilizers, phenolic type stabilizers, triazines, or combinations thereof.
5. The method of making a golf ball of claim 4 , wherein the UVA comprises hydroxyphenyl benzotriazole.
6. The method of making a golf ball of claim 4 , wherein the solvent comprises at least one of acetone, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, or butyl acetate.
7. The method of making a golf ball of claim 6 , wherein the mixture comprises the UVA in an amount of from about 2 wt. % to about 30 wt. % of the mixture.
8. The method of making a golf ball of claim 7 , wherein the layer is a cover layer.
9. The method of making a golf ball of claim 8 , wherein the cover is surrounded by at least one additional layer.
10. The method of making a golf ball of claim 9 , wherein the at least one additional layer comprises a primer coat surrounded by a finishing coat.
11. The method of making a golf ball of claim 9 , wherein each additional layer is at least partially transparent or at least partially translucent, or both.
12. The method of making a golf ball of claim 7 , wherein the layer comprises an outermost layer.
13. The method of making a golf ball of claim 12 , wherein the outermost layer comprises a coating.
14. The method of making a golf ball of claim 7 , wherein the untreated region comprises at least 50% by volume of the layer.
15. The method of making a golf ball of claim 7 , wherein the untreated region comprises at least 90% by volume of the layer.
16. The method of making a golf ball of claim 7 , wherein the treated region comprises at least 50% by volume of the layer.