GOLF BALL HAVING A HOLLOW CENTER

• US 20140194224A1
• Filed: 01/09/2013
• Published: 07/10/2014
• Est. Priority Date: 01/09/2013
• Status: Abandoned Application

• Current Assignee: Acushnet Company (FILA Holdings Corp.)
• Original Assignee: Acushnet Company (FILA Holdings Corp.)
• Inventors: Sullivan, Michael J., Binette, Mark L., Comeau, Brian
• Application Number:
  US13/737,026
• Publication Number:
  US 20140194224A1
• Time in Patent Office: Days
• US Class Current: 473/375
• CPC Class Codes: A63B 37/0027 Polyurea
• CPC Class Codes: A63B 37/0031 Hardness
• CPC Class Codes: A63B 37/0039 characterised by the material
• CPC Class Codes: A63B 37/0043 Hardness
• CPC Class Codes: A63B 37/0044 Hardness gradient
• CPC Class Codes: A63B 37/0056 Hollow; Gas-filled
• CPC Class Codes: A63B 37/006 Physical properties
• 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 37/00776 Slab hardness
• CPC Class Codes: A63B 37/008 Diameter
• CPC Class Codes: A63B 37/00922 whereby hardness of the cover is lower than hardness of the intermediate layers

Abstract

A golf ball includes a spherical inner core shell layer formed from a thermoplastic composition. The shell layer has an outer surface, an inner surface, and an inner diameter to define a hollow center. A thermoplastic outer core layer is formed around the shell layer. An ionomeric inner cover layer and a urethane or urea outer cover layer are formed over the hollow core. The outer cover has a hardness less than the inner cover. The hollow center has a diameter of about 0.15 to 1.1 inches, the shell layer has a surface hardness greater than an inner surface hardness by about 0 to 5 Shore C to define a hardness gradient, and the thermoplastic outer core layer also has a hardness gradient.

Claims

1. A golf ball comprising a hollow core, the golf ball comprising:

a spherical inner core shell layer formed from a first thermoplastic composition, the shell layer having an outer surface, an inner surface, and an inner diameter to define a hollow center;

an outer core layer disposed about the shell layer, the outer core layer comprising a second thermoplastic material;

an inner cover layer disposed about the outer core layer, the inner cover comprising an ionomeric material and having a first hardness; and

an outer cover layer disposed about the inner cover layer, the outer cover comprising a polyurea or a polyurethane and having a second hardness less than the first;

wherein the hollow center has a diameter of about 0.15 to 1.1 inches, the shell layer has a surface hardness greater than an inner surface hardness by about 0 to 5 Shore C to define a first hardness gradient, and the thermoplastic outer core layer has a second hardness gradient different from the first.

2. The golf ball of claim 1, wherein the second hardness gradient is about 0 Shore C.

3. The golf ball of claim 1, wherein the second hardness gradient is a negative hardness gradient of about 1 to 10 Shore C.

4. The golf ball of claim 1, wherein the second hardness gradient is a positive hardness gradient of about 1 to 10 Shore C.

5. The golf ball of claim 1, wherein the golf ball has a first volume and the hollow center has a second volume that is about 2% to 30% of the first volume.

6. The golf ball of claim 1, wherein the spherical inner core shell layer has a coefficient of restitution less than about 0.700 when measured at an incoming velocity of 125 ft/s.

7. The golf ball of claim 1, wherein the outer core layer has a coefficient of restitution, measured at an incoming velocity of 125 ft/s, higher than the coefficient of restitution, measured at an incoming velocity of 125 ft/s, of the inner core shell layer by 10-50%.

8. A golf ball comprising a hollow core, the golf ball comprising:

a spherical inner core shell layer comprising a first thermoplastic material, the shell layer having an outer surface, an inner surface, and an inner diameter to define a hollow center;

an outer core layer comprising a second thermoplastic material;

an intermediate core layer disposed between the shell layer and the outer core layer, the intermediate layer comprising a third thermoplastic material different from the first and second;

an inner cover layer disposed about the outer core layer, the inner cover comprising an ionomeric material and having a first hardness; and

an outer cover layer disposed about the inner cover layer, the outer cover comprising a polyurea or a polyurethane and having a second hardness less than the first;

wherein the hollow center has a diameter of about 0.15 to 1.1 inches, the shell layer has a surface hardness greater than an inner surface hardness by about 0 to 5 Shore C to define a first hardness gradient, and at least one of the thermoplastic outer core layer or the thermoplastic intermediate layer has a second hardness gradient different from the first.

9. The golf ball of claim 8, wherein the second hardness gradient is about 0 Shore C.

10. The golf ball of claim 8, wherein the second hardness gradient is a negative hardness gradient of about 1 to 10 Shore C.

11. The golf ball of claim 8, wherein the second hardness gradient is a positive hardness gradient of about 1 to 10 Shore C.

12. A golf ball comprising a hollow core, the golf ball comprising:

a spherical inner core shell layer comprising a first thermoplastic material, the shell layer having an outer surface, an inner surface, and an inner diameter to define a hollow center;

an outer core layer comprising a second thermoplastic material;

an intermediate core layer disposed between the shell layer and the outer core layer, the intermediate core layer comprising a thermoset rubber composition;

an inner cover layer disposed about the outer core layer, the inner cover comprising an ionomeric material and having a first hardness; and

an outer cover layer disposed about the inner cover layer, the outer cover comprising a polyurea or a polyurethane and having a second hardness less than the first;

wherein the hollow center has a diameter of about 0.15 to 1.1 inches, the shell layer has a surface hardness greater than an inner surface hardness by about 0 to 5 Shore C to define a first hardness gradient, and the thermoplastic outer core layer has a second hardness gradient.

13. The golf ball of claim 12, wherein the second hardness gradient is about 0 Shore C.

14. The golf ball of claim 12, wherein the second hardness gradient is a negative hardness gradient of about 1 to 10 Shore C.

15. The golf ball of claim 12, wherein the second hardness gradient is a positive hardness gradient of about 1 to 10 Shore C.

16. The golf ball of claim 12, wherein the thermoset intermediate core layer has a surface hardness less than an inner surface hardness to define a negative hardness gradient.

17. The golf ball of claim 12, wherein the thermoset intermediate core layer has a surface hardness greater than an inner surface hardness to define a positive hardness gradient.