Method for forming polyurethane covers for golf balls using foam compositions
AssigneeAcushnet Company
InventorsShawn Ricci, Mark L. Binette, Brian Comeau
Life of this patent
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Abstract
The present invention provides methods for producing molded golf balls and the resultant balls. The methods of this invention involve producing foamed polyurethane covers and these methods help reduce dimple distortions and other surface imperfections. These golf balls contain an inner core and outer foamed polyurethane cover. One or more intermediate layers can be disposed between the core and cover. In one embodiment, a castable liquid polyurethane composition containing a foaming agent is dispensed into mold cavities, which are then pressed together to form a foam cover for the ball.
Claims13
A golf ball, comprising:
- i) a core having at least one layer;
- ii) an inner cover layer comprising a non-foamed thermoplastic composition, the inner cover layer being disposed about the core and having a Shore D midpoint hardness in the range of about 55 to about 75;
- and
- iii) an outer cover layer comprising a foamed polyurethane composition disposed about the inner cover layer and having a Shore D outer surface hardness in the range of about 15 to about 60, wherein the outer surface hardness of the outer cover is less than the midpoint hardness of the inner cover layer;
- wherein the foamed polyurethane composition further comprises clay particulate, and wherein the clay particulate has a chemically-modified surface, the surface being chemically-modified with a compound selected from the group consisting of ammonium compounds, protonated amines, organic phosphonium ions, and/or aminocarboxylic acids.
A golf ball formed by a method, the method comprising the steps of:
- i) providing a spherical core having at least one layer;
- ii) providing an upper and lower mold cavity, each mold cavity having an arcuate inner surface defining an inverted dimple pattern;
- iii) introducing a polyurethane composition comprising a foaming agent into at least one mold cavity and loading the core into a mold cavity, wherein the foamed polyurethane composition further comprises clay particulate, and wherein the clay particulate has a chemically-modified surface, the surface being chemically-modified with a compound selected from the group consisting of ammonium compounds, protonated amines, organic phosphonium ions, and/or aminocarboxylic acids;
- iv) joining the mold cavities together under compressive force and heating the polyurethane composition so that the foaming agent is activated and foaming of the composition is initiated and a spherical foamed polyurethane cover layer is formed over the core;
- and
- v) detaching the mold cavities and removing the golf ball, the foamed polyurethane cover layer having a specific gravity of from about 0.90 to about 1.20.
Dependencies are inferred from the claim text.