Golf ball

Patent metadata

Field	Value
Publication number	US-10874908-B2
Application number	US-201916432642-A
Country	US
Kind code	B2
Filing date	Jun 5, 2019
Priority date	Jul 4, 2018
Publication date	Dec 29, 2020
Grant date	Dec 29, 2020

Abstract

A golf ball includes a main body and a paint layer positioned outside the main body. The paint layer includes an inner layer and an outer layer positioned outside the inner layer. When an indentation depth (nm) is measured on a cross-section along a plane passing through a central point of the golf ball when a force of 30 mgf is applied to the cross-section in a direction perpendicular to the cross-section, an indentation depth Di on a cross-section of the inner layer is smaller than an indentation depth Do on a cross-section of the outer layer. A thickness To of the outer layer is larger than a thickness Ti of the inner layer.

First claim

What is claimed is:

1. A golf ball comprising a main body and a paint layer positioned outside the main body, wherein
the paint layer includes an inner layer and an outer layer positioned outside the inner layer,
when an indentation depth (nm) is measured on a cross-section along a plane passing through a central point of the golf ball when a force of 30 mgf is applied to the cross-section in a direction perpendicular to the cross-section, an indentation depth Di on a cross-section of the inner layer is smaller than an indentation depth Do on a cross-section of the outer layer, and
a thickness To of the outer layer is larger than a thickness Ti of the inner layer.

2. The golf ball according to claim 1 , wherein the indentation depth Do is not less than 1000 nm and not greater than 3500 nm.

3. The golf ball according to claim 1 , wherein the indentation depth Di is not less than 100 nm and less than 1000 nm.

4. The golf ball according to claim 1 , wherein the thickness To is not less than 8 μm and not greater than 20 μm.

5. The golf ball according to claim 1 , wherein the thickness Ti is not less than 1 μm and not greater than 10 μm.

6. The golf ball according to claim 1 , wherein a difference (To-Ti) between the thickness To and the thickness Ti is not less than 3 μm and not greater than 17 μm.

7. The golf ball according to claim 1 , wherein a difference (Do-Di) between the indentation depth Do and the indentation depth Di is not less than 1000 nm and not greater than 3100 nm.

8. The golf ball according to claim 1 , wherein
the outer layer is formed from a paint composition including: a base material including a polyrotaxane; and a curing agent including a polyisocyanate compound,
the polyrotaxane has cyclodextrins, a linear molecule threaded through ring structures of the cyclodextrins, and a blocking group which is located at each of both ends of the linear molecule and prevents detachment of the cyclodextrins, and
at least a part of hydroxyl groups of each cyclodextrin is modified with a caprolactone chain via an —O—C3H6—O— group.

9. The golf ball according to claim 8 , wherein a mole ratio (NCO/OH) of an isocyanate group (NCO group) of the curing agent including the polyisocyanate compound to a hydroxyl group (OH group) of the base material including the polyrotaxane is not less than 1.0 and not greater than 2.0.

Assignees

• Sumitomo Rubber Ind

Inventors

• Tanaka Mami
• Tarao Toshiyuki

Classifications

• A63B37/00221 Primary

  characterised by the material · CPC title

• A63B37/0023

  Covers · CPC title

• A63B37/00622

  Surface hardness · CPC title

• A63B37/00621

  Centre hardness · CPC title

• C08J7/043 Primary

  Improving the adhesiveness of the coatings per se, e.g. forming primers (adhesives in the form of films or foils characterised by the primer layers between the polymer carriers and the adhesives C09J7/50) · CPC title