Method of making a golf ball with a multi-layer core

• US 6,302,808 B1
• Filed: 10/15/1998
• Issued: 10/16/2001
• Est. Priority Date: 10/03/1997
• Status: Expired due to Term

• Current Assignee: Acushnet Company (FILA Holdings Corp.)
• Original Assignee: Acushnet Company (FILA Holdings Corp.)
• Inventors: Dalton, Jeffrey L., Cavallaro, Christopher, Boehm, Herbert C.
• Primary Examiner(s): Pierce, William M.
• Application Number:
  US09/172,608
• Time in Patent Office: 1,097 Days
• Field of Search: 473/373, 473/365, 473/376, 473/371
• US Class Current: 473/371
• CPC Class Codes: A63B 37/0003 Golf balls
• CPC Class Codes: A63B 37/0031 Hardness
• CPC Class Codes: A63B 37/0033 Thickness
• CPC Class Codes: A63B 37/0037 Flexural modulus; Bending stiffness
• CPC Class Codes: A63B 37/0043 Hardness
• CPC Class Codes: A63B 37/0045 Thickness
• CPC Class Codes: A63B 37/00621 Centre hardness
• CPC Class Codes: A63B 37/0064 Diameter
• CPC Class Codes: A63B 37/0076 Multi-piece balls, i.e. having two or more intermediate layers
• CPC Class Codes: A63B 37/008 Diameter
• CPC Class Codes: A63B 37/0092 Hardness distribution amongst different ball layers
• CPC Class Codes: A63B 45/00 Apparatus or methods for manufacturing balls working of plastics or substances in a plastic state B29
• CPC Class Codes: B29C 2043/3644 Vacuum bags; Details thereof, e.g. fixing or clamping
• CPC Class Codes: B29C 43/146 for making multilayered articles
• CPC Class Codes: B29C 43/18 incorporating preformed parts or layers, e.g. compression moulding around inserts or for coating articles B29C43/206 takes precedence
• CPC Class Codes: B29C 43/305 Making multilayered articles
• CPC Class Codes: B29C 70/70 Completely encapsulating inserts B29C70/86 takes precedence
• CPC Class Codes: B29D 99/0042 Producing plain balls hollow balls B29D22/04
• CPC Class Codes: B29K 2105/256 Sheets, plates, blanks or films
• CPC Class Codes: B29L 2031/52 Sports equipment ; Games; Articles for amusement; Toys B29L2031/54 takes precedence
• CPC Class Codes: B29L 2031/54 : Balls

Abstract

An improved golf ball comprising a center having a first hardness, a first layer surrounding the center, comprised of a second material, a second layer surrounding the first layer, comprised of a third material, a third layer surrounding the second layer, comprised of a fourth material, and a cover of a cover material surrounding the third layer wherein each layer has a different hardness.

Claims

1. A golf ball comprising:

a) a center comprised of a first polybutadiene rubber having a first hardness and having a diameter of at least 1 inch;

b) a first layer surrounding the center, comprised of a second material and having a second hardness and a thickness of less than 0.1 inch;

c) a second layer surrounding the first layer, comprised of a third material and having a third hardness and a thickness of less than 0.1 inch;

d) a third layer surrounding the second layer, comprised of a fourth material and having a fourth hardness and a thickness of less than 0.1 inch; and

e) a cover of a cover material surrounding the third layer;

wherein each of the first, second and third layers is a solid layer.

2. The golf ball of claim 1, wherein:

a) the second hardness is different from the first polybutadiene rubber;

b) the third hardness is different from the first polybutadiene rubber and the second hardness;

c) the fourth hardness is different from the first polybutadiene rubber, the second hardness and the third hardness; and

d) the cover material has a fifth hardness different from the first polybutadiene rubber, the second hardness, the third hardness and the fourth hardness.

3. The golf ball of claim 2, wherein each of the first, second and third layers has a thickness less than 0.05 inch.

4. The golf ball of claim 3, wherein the center has a diameter of about 1.25 to 1.45 inch.

5. The golf ball of claim 4 wherein the center, the first, second and third layer materials and the cover material are selected so that the ball has a compression of less than 85.

6. The golf ball of claim 5, wherein the ball has a compression of less than 80.

7. The golf ball of claim 5, wherein:

a) the center has a Shore C hardness at a center point thereof of less than 70;

b) the first layer is harder than the center;

c) the second layer is harder than the first layer; and

d) the third layer is harder than the second layer.

8. The golf ball of claim 5, wherein:

a) the first layer has a Shore C hardness of 70 to 75;

b) the second layer has a Shore C hardness of 72 to 77; and

c) the third layer has a Shore C hardness of 75 to 80.

9. The golf ball of claim 7, wherein the cover has a Shore D hardness of less than 60.

10. The golf ball of claim 4, wherein the center has a Shore C hardness of greater than 75.

11. The golf ball of claim 10, wherein:

a) the first layer is softer than the center;

b) the second layer is softer than the first layer; and

c) the third layer is softer than the second layer.

12. The golf ball of claim 11, wherein:

a) the first layer has a Shore C hardness of 75 to 72;

b) the second layer has a Shore C hardness of about 73 to 70; and

c) the third layer has a Shore C hardness of less than about 70.

13. The golf ball of claim 1, wherein at least one of the first, second, third and fourth materials are thermoset materials.

14. The golf ball of claim 1, wherein at least one of the first, second, third, and fourth materials comprises a polybutadiene rubber.

15. A golf ball comprising:

a) a solid center comprised of a first polybutadiene rubber having a first hardness;

b) a solid first layer surrounding the center, comprised of a second polybutadiene rubber material and having a thickness of less than 0.1 inch;

c) a solid second layer surrounding the first layer, comprised of a third polybutadiene rubber material and having a thickness of less than 0.1 inch;

d) a solid third layer surrounding the second layer, comprised of a fourth polybutadiene rubber material and having a thickness of less than 0.1 inch; and

e) a cover of a cover material surrounding the third layer.

16. The golf ball of claim 15, wherein:

a) the second material hardness has a different hardness from the first polybutadiene rubber;

b) the third material has a different hardness from the first polybutadiene rubber and the second material;

c) the fourth material has a different hardness from the first polybutadiene rubber, the second material and the third material; and

d) the cover material has a different hardness from the first polybutadiene rubber, the second material, the third material, and the fourth material.