Golf ball with an improved intermediate layer

1. A golf ball comprising:

a core;

a cover; and

at least one intermediate layer disposed between the cover and core, the intermediate layer comprising a composite of a binding material and an interstitial material that have dissimilar material properties, wherein a first effective material property of the intermediate layer in a first direction is different from a second effective material property in a second direction, and wherein the interstitial material has a long-time shear modulus and the binding material has a binding material long-time shear modulus and the ratio of the interstitial material long-time shear modulus to the binding material long-time shear modulus is about 30:1 or less.

2. The golf ball of claim 1 , wherein the first direction of the first effective material property is in the radial direction of the ball and the second direction of the second effective material property is in the circumferential direction of the ball.

3. The golf ball of claim 1 , wherein the interstitial material is distributed symmetrically.

4. The golf ball of claim 1 , wherein the interstitial material is radially oriented.

5. The golf ball of claim 1 , wherein the ratio of the interstitial and binding material long-time shear moduli is between about 5:1 and about 10:1.

6. The golf ball of claim 1 , wherein the intermediate layer has a thickness between about 0.080 inches and about 0.340 inches.

7. The golf ball of claim 1 , wherein effective material properties of intermediate layer comprise a transverse effective material property and an axial effective material property, and wherein said effective material properties may be estimated as:

X axial =X f +(1−φ f ) X m

X

trans

=

X

f

⁢

X

m

X

m

⁢

φ

f

+

(

1

-

φ

f

)

⁢

X

f

where:

X axial is the axial effective material property of the intermediate layer;

X trans is the transverse effective material property of the intermediate layer;

X f is the material property of the interstitial material;

X m is the material property of the binding material; and

φ f is the volume fraction of interstitial material to binding material.

8. The golf ball of claim 1 , wherein the interstitial material is formed of a continuous piece of material.

9. A golf ball comprising:

a core;

a cover; and

at least one intermediate layer disposed between the core and the cover, the intermediate layer being formed of a binding material and an interstitial material distributed in the binding material, and wherein the effective elastic modulus of the intermediate layer is lower under forces applied in the radial direction and higher under forces applied in the tangential direction, and wherein the binding material has a binding material elastic modulus and the interstitial material has an interstitial material elastic modulus and the ratio of the interstitial material elastic modulus to the binding material elastic modulus is about 3:1 or greater.

10. The golf ball of claim 9 , wherein the interstitial material is distributed symmetrically.

11. The golf ball of claim 9 , wherein the interstitial material is radially oriented.

12. The golf ball of claim 9 , wherein the ratio of the interstitial and binding material elastic moduli is between about 5:1 and about 10:1.

13. The golf ball of claim 9 , wherein the interstitial material has an interstitial material long-time shear modulus and the binding material has a binding material long-time shear modulus and the ratio of the interstitial material long-time shear modulus to the binding material long-time shear modulus is about 30:1 or less.

14. The golf ball of claim 13 , wherein the ratio of the interstitial and binding material long-time shear moduli is between about 5:1 and about 10:1.

15. A golf ball comprising:

a core;

a cover; and

at least one intermediate layer disposed between the cover and core, the intermediate layer comprising a composite of two dissimilar materials, wherein a first effective material property of the intermediate layer in a first direction is different from a second effective material property in a second direction, and wherein the ratio of the length to cross-sectional area of the interstitial material is about 30:1 or greater.

16. The golf ball of claim 15 , wherein the ration of the length to cross-sectional area of the interstitial material is about 60:1 or greater and less than about 200:1.

17. A golf ball comprising:

a core;

a cover; and

at least one intermediate layer disposed between the cover and core, the intermediate layer comprising a composite of a binding material and an interstitial material that have dissimilar material properties such that the intermediate layer has effective material properties based upon the material properties of the binding material and the interstitial material, and wherein the interstitial material properties predominate the effective material properties of the intermediate layer when the ratio of normal to tangential forces imparted on the ball when struck by a club is about 2.0 or greater.

18. The golf ball of claim 17 , wherein the interstitial material properties predominate the effective material properties of the intermediate layer when the ratio of normal to tangential forces imparted on the ball is about 2.25 or greater.

19. A golf ball comprising:

a core;

a cover; and

at least one intermediate layer disposed between the cover and core, the intermediate layer comprising a composite of a binding material and an interstitial material that have dissimilar material properties such that the intermediate layer has effective material properties based upon the material properties of the binding material and the interstitial material, and wherein the binding material properties predominate the effective material properties of the intermediate layer when the ratio of normal to tangential forces imparted on the ball when struck by a club is about 1.75 or less.

20. The golf ball of claim 19 , wherein the binding material properties predominate the effective material properties of the intermediate layer when the ratio of normal to tangential forces imparted on the ball is about 1.25 or less.

21. A golf ball comprising:

a core;

a cover; and

at least one intermediate layer disposed between the core and the cover, the intermediate layer being formed of a binding material and an interstitial material distributed in the binding material, and wherein the effective elastic modulus of the intermediate layer is lower under forces applied in the radial direction and higher under forces applied in the tangential direction, and wherein the interstitial material has an interstitial material long-time shear modulus and the binding material has a binding material long-time shear modulus and the ratio of the interstitial material long-time shear modulus to the binding material long-time shear modulus is about 30:1 or less.

22. The golf ball of claim 21 , wherein the interstitial material is distributed symmetrically.

23. The golf ball of claim 21 , wherein the interstitial material is radially oriented.

24. The golf ball of claim 21 , wherein the binding material has a binding material elastic modulus and the interstitial material has an interstitial material elastic modulus and the ratio of the interstitial material elastic modulus to the binding material elastic modulus is about 3:1 or greater.

25. The golf ball of claim 21 , wherein the ratio of the interstitial and binding material elastic moduli is between about 5:1 and about 10:1.

26. The golf ball of claim 21 , wherein the interstitial material has an interstitial material long-time shear modulus and the binding material has a binding material long-time shear modulus and the ratio of the interstitial material long-time shear modulus to the binding material long-time shear modulus is about 30:1 or less.

27. The golf ball of claim 26 , wherein the ratio of the interstitial and binding material long-time shear moduli is between about 5:1 and about 10:1.