Golf club head with improved composite material

Abstract

A golf club with a multi-material face is disclosed herein. More specifically, the present invention discloses a golf club head with a composite material wherein the composite material has a significantly lower Fiber Areal Weight (FAW) less than about 50 grams per meters square (gsm). In one embodiment of the invention the golf club head has a striking face that forms a pocket, wherein the pocket is filled with a secondary material having a lower density to improve the performance of the golf club head. The multi-material face disclosed in accordance with the present invention may generally have an inter laminar shear strength of greater than about 60 MPa, most preferably greater than about 60 MPa and less than about 145 MPa.

What is claimed is: 
     
         1 . A golf club head comprising:
 a hollow unitary shell, made out of a first material having a first density, forming at least one opening of said golf club head;   at least one composite layer, configured to cover said at least one opening;   wherein said composite layer has a Fiber Areal Weight (FAW) of less than about 50 gsm.   
     
     
         2 . The golf club head of  claim 1 , wherein said composite layer has a Fiber Areal Weight (FAW) of less than about 40 gsm. 
     
     
         3 . The golf club head of  claim 2 , wherein said composite layer has a Fiber Areal Weight (FAW) of between about 10 gsm and about 30 gsm. 
     
     
         4 . The golf club head of  claim 3 , wherein said composite layer has an interlaminar shear strength of greater than about 60 MPa. 
     
     
         5 . The golf club head of  claim 4 , wherein said composite layer has an interlaminar shear strength of greater than about 70 MPa. 
     
     
         6 . The golf club head of  claim 5 , wherein said composite layer has an interlaminar shear strength of greater than about 75 MPa. 
     
     
         7 . The golf club head of  claim 3 , further comprising a metallic striking face layer, positioned to encompass a frontal external portion of said at least one composite layer. 
     
     
         8 . The golf club head of  claim 7 , wherein said metallic striking face layer form a return portion, having a length of greater than about 15 mm. 
     
     
         9 . The golf club head of  claim 8 , wherein said metallic striking face layer forms a return portion, having a length of greater than about 17 mm. 
     
     
         10 . The golf club head of  claim 9 , wherein said metallic striking face layer forms a return portion, having a length of greater than about 20 mm. 
     
     
         11 . The golf club head of  claim 3 , wherein said composite layer is made out of a material having a strain to failure percentage of greater than about 1.5% and less than about 10%. 
     
     
         12 . The golf club head of  claim 11 , wherein said composite layer is made out of a material having a strain to failure percentage of greater than about 2% and less than about 8%. 
     
     
         13 . The golf club head of  claim 12 , wherein said composite layer is made out of a material having a strain to failure percentage of about 2.5%. 
     
     
         14 . A golf club head comprising:
 a hollow unitary shell, made out of a first material having a first density, forming at least one opening of said golf club head;   at least one composite layer, made out of a second material having a second density, configured to cover said at least one opening;   wherein said composite layer has a Fiber Areal Weight (FAW) of less than about 50 gsm, and   wherein said second material has a density of less than about 1.70 g/cm 3 .   
     
     
         15 . The golf club head of  claim 14 , wherein said golf club head has a First Peak Frequency to Volume Ratio greater than about 7.0 hertz/cc and less than about 15.0 hertz/cc. 
     
     
         16 . The golf club head of  claim 14 , wherein said golf club head has a First Peak Frequency to Volume Ratio of greater than about 9.0 hertz/cc and less than about 13.0 hertz/cc. 
     
     
         17 . The golf club head of  claim 14 , wherein said golf club head has a First Peak Frequency to Volume Ratio of about 8.0 hertz/cc. 
     
     
         18 . The golf club head of  claim 14 , wherein said at least one composite layer has a FAW of about 40 gsm, while a resin of said composite has an areal weight of about 26.67 gsm. 
     
     
         19 . The golf club head of  claim 14 , wherein said at least one composite layer has a FAW of about 30 gsm, while a resin of said composite has an areal weight of about 20 gsm. 
     
     
         20 . The golf club head of  claim 14 , wherein said at least one composite layer has a FAW of about 12 gsm, while a resin of said composite has an areal weight of about 8 gsm.