Golf ball and method of manufacture

Patent metadata

Field	Value
Publication number	US-9682283-B2
Application number	US-201514729207-A
Country	US
Kind code	B2
Filing date	Jun 3, 2015
Priority date	Jun 27, 2014
Publication date	Jun 20, 2017
Grant date	Jun 20, 2017

Abstract

In a golf ball having a core and a cover of one or more layer encasing the core, an outermost layer of the cover is molded of a thermoplastic material selected from the group consisting of polyurethane, polyurea and mixtures thereof, and the surface of the cover is treated with a polyisocyanate compound that is free of organic solvent. A method of manufacturing the golf ball is also described. Such golf balls are endowed with an excellent spin performance and scuff resistance, in addition to which productivity of the golf balls is high.

First claim

The invention claimed is:

1. A golf ball comprising a core and a cover of one or more layer encasing the core, wherein the cover has an outermost layer molded of an ether type thermoplastic polyurethane material, and a surface of the cover is treated with a polyisocyanate compound that is free of organic solvent, wherein the rebound resilience of the outermost layer prior to the above surface treatment is at least 35%, and wherein the polyisocyanate compound is a mixture of 4,4′-diphenylmethane diisocyanate (MDI) and polymethylene polyphenyl polyisocyanate containing 41 to 59% by weight of MDI and the viscosity at 25° C. of the polyisocyanate compound is from 25 to 180 mPa·s.

2. The golf ball according to claim 1 , wherein the thermoplastic material of which the outermost layer is molded has a resin hardness, expressed in terms of Shore D hardness, of from 30 to 65.

3. The golf ball according to claim 1 , wherein the outermost layer has a thickness of from 0.3 to 3.0 mm.

4. The golf ball according to claim 1 , wherein the polyurethane or polyurea serving as the thermoplastic material of which the outermost layer material is molded has an isocyanate component which is one or a mixture of two or more selected from the group consisting of
tolylene-2,6-diisocyanate, tolylene-2,4-diisocyanate,
4,4′-diphenylmethane diisocyanate,
polymethylene polyphenyl polyisocyanate,
1,5-diisocyanatonaphthalene,
isophorone diisocyanate (including isomer mixtures),
dicyclohexylmethane-4,4′-diisocyanate,
hexamethylene-1,6-diisocyanate, m-xylylene diisocyanate,
hydrogenated xylylene diisocyanate, tolidine diisocyanate,
norbornene diisocyanate and
1,4-bis(isocyanatomethyl)cyclohexane.

5. The golf ball according to claim 1 wherein, following treatment of the cover surface, the ball has a surface hardness, expressed in terms of Shore D hardness, of from 30 to 70.

6. The golf ball according to claim 1 , wherein the polyisocyanate compound at normal temperature is a dark brown liquid or a blackish brown liquid.

Assignees

• Bridgestone Sports Co Ltd

Inventors

• Nagasawa Hiroyuki
• Mochizuki Katsunobu

Classifications

• A63B37/0023

  Covers · CPC title

• A63B37/0033

  Thickness · CPC title

• B29C2071/0018

  Absorbing ingredients, e.g. drugs, flavourings, UV screeners, embedded in the articles · CPC title

• A63B45/00 Primary

  Apparatus or methods for manufacturing balls (working of plastics or substances in a plastic state B29) · CPC title

• B29C71/0009

  using liquids, e.g. solvents, swelling agents (spectacle cases, e.g. for cleaning contact lenses A45C11/04; disinfecting or sterilising contact lenses A61L12/00, using liquid substances A61L2/20; cleaning involving the use of liquid in general B08B3/00; for hydrating contact lenses B29D11/00067) · CPC title