Golf balls having sound-altered layers and methods of manufacture

Abstract

Golf ball covers incorporate base material compositions including a sound-altering material for selectively enhancing or dampening the acoustic output of a golf ball when it is struck. A ratio in the composition by weight of base material to sound-altering material ranges between 99.9:0.1 and 92:8. The invention allows for the altering of the sound of the golf ball while retaining the mechanical properties of the golf ball cover.

1 . A golf ball having a core and one or more cover layers encasing the core, wherein at least one of the one or more cover layers comprises a composition, the composition comprising: 
 a base material; and    a sound-altering material having outer surfaces that have been treated to promote adhesion;    wherein the weight ratio in the composition of the base material to the sound-altering material is between 98:2 and about 95:5;    and wherein the sound-altering material is configured to alter the sound produced when the golf ball is struck without substantially altering the golf ball's hardness and compression.    
   
   
       2 . The golf ball of  claim 1 , wherein the sound-altering material is a sound-enhancing material configured to increase the sound output produced when the golf ball is struck.  
   
   
       3 . The golf ball of  claim 2 , wherein the sound-enhancing material comprises metal stearate.  
   
   
       4 . The golf ball of  claim 3 , wherein the sound-enhancing material comprises zinc stearate or calcium stearate.  
   
   
       5 - 6 . (canceled)  
   
   
       7 . The golf ball of  claim 1 , wherein the sound-altering material is a sound-dampening material configured to increase the sound output produced when the golf ball is struck.  
   
   
       8 . The golf ball of  claim 7 , wherein the sound-dampening material comprises a carbonate or a sulfate.  
   
   
       9 . The golf ball of  claim 8 , wherein the sulfate is barium sulfate.  
   
   
       10 . The golf ball of  claim 7 , wherein the sound-dampening material comprises hollow glass beads.  
   
   
       11 - 15 . (canceled)  
   
   
       16 . The golf ball of  claim 1 , wherein the base material comprises a non-ionomeric polymer, an ionomeric polymer, or mixtures thereof.  
   
   
       17 . The golf ball of  claim 16 , wherein the non-ionomeric polymer comprises thermoplastic polyurethane, thermoset polyurethane, polyamide, silicone material, thermoplastic elastomers, syndiotactic 1,2-polybutadiene, ethylene-vinyl-acetate, styrenic copolymers, styrenic terpolymers, polymers having functional groups, or mixtures thereof.  
   
   
       18 . The golf ball of  claim 16 , wherein the ionomeric polymer comprises a copolymeric ionomer, a terpolymeric ionomer, or mixtures thereof.  
   
   
       19 . The golf ball of  claim 16 , wherein the base material further comprises UV stabilizers, photostabilizers, antioxidants, colorants, dispersants, mold releasing agents, processing aids, fibers, fillers, or mixtures thereof.  
   
   
       20 . The golf ball of  claim 1 , wherein the cover layers comprise an outer cover layer, and the outer cover layer comprises the composition.  
   
   
       21 . The golf ball of  claim 1 , wherein the cover layers comprise an inner cover layer, and the inner cover layer comprises the composition.  
   
   
       22 . The golf ball of  claim 20 , further comprising one or more intermediate layers situated between the core and the cover layers.  
   
   
       23 . The golf ball of  claim 20 , wherein the core comprises an inner core and one or more outer cores encasing the inner core.  
   
   
       24 . The golf ball of  claim 20 , wherein the core comprises liquid.  
   
   
       25 . The golf ball of  claim 20 , farther comprising a layer of rubber thread situated between the core and the cover layers of the golf ball.  
   
   
       26 . The golf ball of  claim 1 , further comprising a layer of rubber thread situated between the core and the cover layers of the golf ball, wherein the rubber thread comprises the composition.  
   
   
       27 . The golf ball of  claim 1 , wherein an acoustic pulse difference between the base material combined with the sound-altering material and the base material has a value between 0.01 and 0.09 Pascals.  
   
   
       28 . The golf ball of  claim 1 , wherein an acoustic pulse difference between the base material with the sound-altering material and the base material has a value greater than 0.05 Pascals.  
   
   
       29 . A method for preparing a golf ball layer, comprising the steps of: 
 preparing a composition comprising 
 a base material, and  
 a sound-altering material having outer surfaces that have been treated to promote adhesion,  
 wherein the weight ratio in the composition of the base material to the sound-altering material is between 98:2 and about 95:5; and  
   forming the composition into a golf ball layer positioned around a golf ball core, wherein the sound-altering material is configured to alter the sound produced when the golf ball is struck, without substantially altering the golf ball's hardness and compression.    
   
   
       30 . The method as defined in  claim 29 , wherein the step of forming the composition into a layer comprises injection molding the composition to form the layer.  
   
   
       31 . The method as defined in  claim 29 , wherein the step of preparing a composition comprises a step of dry-blending the composition.  
   
   
       32 . The method as defined in  claim 29 , wherein the step of preparing a composition comprises a step of mixing the composition using a mill, internal mixer or extruder.  
   
   
       33 . The method as defined in  claim 29 , wherein the step of preparing a composition comprises incorporating into the composition a non-ionomeric polymer, an ionomeric polymer, or mixtures thereof.  
   
   
       34 . The method as defined in  claim 29 , wherein the step of preparing a composition comprises: 
 preparing a concentrate by premixing the sound-altering material with the base material; and    introducing the concentrate into a mixture comprising the base material.    
   
   
       35 . The method as defined in  claim 29 , wherein the step of forming the composition into a layer comprises: 
 forming the composition into half cups;    positioning the half cups over the core such that the core is covered by the half cups; and    increasing thermal energy to and pressure on the half cups such that the half cups are bonded together to form the layer.