Golf balls incorporating cerium oxide nanoparticles

Abstract

The invention is directed to a golf ball providing improved UV resistance, abrasion resistance and hydrophobicity comprising cerium oxide nanoparticles having a particle size within the wavelength of visible light. The golf ball of the invention may comprise the cerium oxide nanoparticles in any or all of outer core layers, intermediate layers, inner cover layers, outer cover layers and even as a coating composition in an amount of from about 0.5 wt % to about 10 wt % of the respective layer. The cerium oxide nanoparticles may be randomly dispersed within a layer or coating, or alternatively, the cerium oxide nanoparticles may be ordered in an array within the layer or coating.

Description

FIELD OF THE INVENTION[0001]Golf balls incorporating materials which improve UV resistance, abrasion resistance and hydrophobicity.BACKGROUND OF THE INVENTION[0002]Golf balls are generally divided into two classes: solid and wound. Solid golf balls include a solid core of one or more layers, a cover of one or more layers, and optionally one or more intermediate layers. Wound golf balls typically include a solid, hollow, or fluid-filled center, surrounded by tensioned elastomeric material, and a cover. Solid golf balls, as compared with wound balls, are more durable and resilient, providing better distance than wound balls due to their higher initial velocity upon impact with a club face. Meanwhile, the wound construction provides a softer “feel”, lower compression and higher spin rate—characteristics often preferred by accomplished golfers who are able to control the ball's flight and positioning.[0003]Notwithstanding a golf ball's particular construction, it is important that the g...

AI Technical Summary

Benefits of technology

[0029]Meanwhile, the difference in the b chroma dimension Δb*, yellow to blue, is also a way to quantify the light stability of a cover. In one embodiment, the Δb* for the cover of the golf ball of the invention is less than about 8 after 5 days. In another embodiment, the Δb* for the cover of the golf ball of the invention is about 6.75 or less after 5 days. In yet another embodiment, the Δb* for the cover of the golf ball of the invention is about 6.5 or less after 5 days. In still another embodiment, the Δb* for the cover of the golf ball of the invention is about 6.25 or less after 5 days or even 6.0 or less after 5 days.

[0056]Meanwhile, the inventive golf ball comprising cerium oxide nanoparticles as disclosed and claimed herein is versatile in that a wide range of Shore C and Shore D hardnesses may be chosen and coordinated for each of the core, core layers, intermediate layers and cover layers as known by those skilled in the golf ball art for achieving desired feel and playing characteristics. In this regard, cerium oxide nanoparticles will serve as filler in order to increase the density or specific gravity of a substrate into which they are mixed, whether it be an outer core layer, intermediate layer, inner cover layer, outer cover, or in a coating.

Problems solved by technology

Yellowing is a common problem in golf ball covers made of thermoset or thermoplastic polyurethanes or polyureas due to the presence of an aromatic component in each—e.g., aromatic diisocyanate, polyol, or polyamine.

Then, when electrons and holes migrate to the surface, they react with oxygen, water or hydroxyls to form free radicals which cause polymeric degradation, resulting in yellowing of an otherwise white cover surface.

Golf ball manufacturers have found it challenging to address this aesthetic aspect without compromising the “soft feel” desired by players.

Moisture penetration issues typically arise, for example, when golf ball manufacturers use polybutadiene cores cross-linked with peroxide and / or zinc diacrylate in the golf ball core.

Water moisture vapor reduces the resiliency of the core and degrades its properties.

However, it is more difficult to control or impart spin to balls with hard covers.

To date, manufacturers have found it difficult to simultaneously improve / preserve aesthetic qualities and address issues affecting player performance.