| Multi-layer golf ball having velocity gradient from slower center to faster cover -> Monitor Keywords |
|
|
  Multi-layer golf ball having velocity gradient from slower center to faster coverUSPTO Application #: 20080096693Title: Multi-layer golf ball having velocity gradient from slower center to faster cover Abstract: The present invention is directed to multi-layer golf balls having a center, a cover layer, and at least one intermediate layer between the core and the cover layer. The center, the at least one intermediate layer and the cover are constructed to have different initial velocities and COR such that the gradients of initial velocities and COR progress from a slower center to a faster cover. (end of abstract) Agent: Acushnet Company - Fairhaven, MA, US Inventors: Herbert C. Boehm, Michael J. Sullivan, Steven Aoyama, David A. Bulpett, Derek A. Ladd USPTO Applicaton #: 20080096693 - Class: 473374000 (USPTO) Related Patent Categories: Games Using Tangible Projectile, Golf, Ball, Particular Unitary Or Layered Construction, Diverse Layer Between Spherical Core And Cover The Patent Description & Claims data below is from USPTO Patent Application 20080096693. Brief Patent Description - Full Patent Description - Patent Application Claims
CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation of U.S. patent application Ser. No. 11/061,338, filed on Feb. 18, 2005, which is a continuation-in-part of U.S. patent application Ser. No. 10/773,906, now U.S. Pat. No. 7,255,656, the entire disclosures of which are hereby incorporated herein by reference. FIELD OF THE INVENTION [0002] This invention is related to multi-layer golf balls having a coefficient of restitution gradient that progresses from a slower center to a faster cover. BACKGROUND OF THE INVENTION [0003] Two-layer golf balls are typically made with a single solid core encased by a cover. These balls are generally most popular among recreational golfers, because they are durable and provide maximum distance. Typically, the solid core is made of polybutadiene cross-linked with zinc diacrylate and/or similar crosslinking agents. The cover material is a tough, cut-proof blend of one or more materials known as ionomers, such as SURLYN.RTM., sold commercially by DuPont or IOTEK.RTM., sold commercially by Exxon. [0004] Multi-layer golf balls may have multiple core layers, multiple intermediate layers, and/or multiple cover layers. They tend to overcome some of the undesirable features of conventional two-layer balls, such as hard feel and less control, while maintaining the positive attributes, such as increased initial velocity and distance. Further, it is desirable that multi-layer balls have a "click and feel" similar to wound balls. [0005] Additionally, the spin rates of golf balls affect the overall control of the balls in accordance to the skill level of the players. Low spin rates provide improved distance, but make golf balls difficult to stop on shorter shots, such as approach shots to greens. High spin rates allow more skilled players to maximize control of the golf ball, but adversely affect driving distance. To strike a balance between the spin rates and the playing characteristics of golf balls, additional layers, such as intermediate layers, outer core layers and inner cover layers are added to the solid core golf balls to improve the playing characteristics of the ball. [0006] The patent literature discloses a number of multi-layer golf balls. U.S. patent application Ser. No. 10/773,906 which is commonly owned and incorporated herein by reference in its entirety, is directed to an improved multi-layer golf ball displaying certain spin profile. The ball has a generally rigid, thermosetting polybutadiene outer core surrounding a relatively soft, low compression inner core. The inner core has a hardness that is less than the hardness of the outer core, and a specific gravity that is less than or equal to the specific gravity of the outer core. The inner core and outer core are formulated to provide a combined overall core compression of greater than about 50. [0007] U.S. patent application Ser. No. 09/853,252, which is commonly owned and incorporated by reference in its entirety, is directed to golf balls having a cover comprising three or more layers: an inner cover layer, an outer cover layer, and an intermediate cover layer. The outer cover layer comprises a composition formed of a reactive liquid material, and the combination of the thickness of the cover layers is about 0.125 inch. Golf balls prepared accordingly can exhibit substantially the same or higher coefficient of restitution ("COR"), with a decrease in compression or flexural modulus, compared to golf balls of conventional construction. The resultant golf balls typically have a COR of greater than about 0.7 and an Atti compression of at least about 40. [0008] U.S. patent application Ser. No. 10/279,506, which is also commonly owned, and incorporated by reference in its entirety, is directed to a golf ball comprising an inner core, an outer core, and a cover. At least a layer of the golf ball is made from a low compression, high COR material, and is being supported by a low deformation, high compression layer. The resulting golf ball has high COR at high and low impact speeds and low compression for controlled greenside play. [0009] U.S. Pat. No. 6,645,089 to Tsuoda et al. and U.S. Pub. Pat. App. Nos. 2002/0019268 and 2002/0042308 by Tsunoda, et al. are directed to a golf ball comprising a 6-layer core. The modulus of elasticity of each layer of the core progresses from lower to higher modulus in the direction from the center to the outermost core layer. [0010] U.S. Pat. No. 6,419,595 to Maruko et al. is directed to a 5-piece golf ball comprising a single core and 4 cover layers. The innermost cover layer has less than 60 Shore D hardness, the next cover layer has greater than 45 Shore D hardness, and the outermost cover layer is harder than the third cover layer. [0011] However, there remains a need to provide multi-layer golf balls having velocity gradient that progresses from a slower center to a faster cover to match the balls to the players' swing speed. SUMMARY OF THE INVENTION [0012] This invention is directed to a multi-layer golf ball comprising a core, a cover layer, and at least one intermediate layer between the core and the cover layer. The ball may have an unlimited number of intermediate layers, but typically will have from 1 to 8 and each layer of the ball has a different coefficient of restitution value. The coefficient of restitution gradient from the center to the outermost layer is from low to high, or the initial velocity gradient from the center to the cover layer is from slow to fast. [0013] For the purposes of this patent, the center is the innermost core layer and any outer core layer will be considered an intermediate layer. [0014] According to the present invention, the center has a COR value of less than 0.800, preferably less than 0.780. The center and the first intermediate layer have a combined COR value of at least 0.500, preferably at least 0.750. The center, the first intermediate layer, and the second intermediate layer have a combined COR value of at least 0.700, more preferably at least 0.760. The golf ball has a combined COR value of at least 0.800, preferably at least 0.805. [0015] In another aspect of the invention, for golf balls with four layers or more the combined COR of a subassembly is 0.003 lower than the combined COR of that subassembly plus the next outer layer, preferably 0.005, and more preferably 0.010. For golf balls with three layers, the COR of the inner two layers is at least 0.015 lower than the COR for all three layers, and more preferably 0.018 lower and most preferably 0.020 lower. [0016] In a different aspect of the invention, the change in COR is normalized as the change in COR from one subassembly to the next larger subassembly in the radial direction per the thickness of the next larger assembly in the radial direction. For golf balls with four layers or more, the normalized combined COR of a subassembly is 0.00010 per thousandth of an inch less than the normalized combined COR of that subassembly plus the next outer layer, preferably 0.00020 per thousandth, and more preferably 0.00030 per thousandth. For golf balls with three layers, the normalized COR is 0.00020 per thousandth, preferably 0.00030 per thousandth and more preferably 0.00040 per thousandth. [0017] In another aspect of the invention, the material of each individual layer taken alone or independent of the subassembly has a coefficient of restitution that is higher than or the same as the coefficient of restitution of the layer beneath it. [0018] The center of the multi-layer golf ball may comprise any thermoplastic and/or thermosetting polymer(s) including, but not limited to, a polybutadiene, a polyurethane, a polyurea, a highly neutralized polymer, a silicone, a polyolefin, a polyamide, a polyester, a polyether amide, a polyester amide, or a blend thereof, metallocene or other single site catalyzed polymers, styenic block copolymers, ionomers, thermoplastic elastomers, fluoropolymers, styrene butadiene rubber, natural or synthetic polyisoprene, butyl or halobutyl rubber, or blends thereof. [0019] The intermediate layers may comprise a polybutadiene, a polyurethane, a polyurea, a highly neutralized polymer, a silicone, a polyolefin, a polyamide, a polyester, a polyether amide, a polyester amide, or a blend thereof. [0020] The cover layer may comprise a highly neutralized polymer formed from a reaction between acid groups on a polymer, a suitable source of cation, and an organic acid or the corresponding salt, and the extent of neutralization is at least 80%, preferably at least 90%, and more preferably 100%. Suitable source of cation is selected from magnesium, sodium, zinc, lithium, potassium and calcium, and the organic acid or the corresponding salt is selected from oleic acid, salt of oleic acid, stearic acid, salt of stearic acid, behenic acid, salt of behenic acid or combination thereof. The cover layer can also be a product of a reaction mixture comprising a polybutadiene, a cis-to-trans catalyst, a free radical source, a crosslinking agent, and a filler. Continue reading... Full patent description for Multi-layer golf ball having velocity gradient from slower center to faster cover Brief Patent Description - Full Patent Description - Patent Application Claims Click on the above for other options relating to this Multi-layer golf ball having velocity gradient from slower center to faster cover patent application. ###  How KEYWORD MONITOR works... a FREE service from FreshPatents1. Sign up (takes 30 seconds). 2. Fill in the keywords to be monitored. 3. Each week you receive an email with patent applications related to your keywords. Start now! - Receive info on patent apps like Multi-layer golf ball having velocity gradient from slower center to faster cover or other areas of interest. ### Previous Patent Application: Multi-layer golf ball Next Patent Application: Golf tee Industry Class: Games using tangible projectile ### FreshPatents.com Support Thank you for viewing the Multi-layer golf ball having velocity gradient from slower center to faster cover patent info. IP-related news and info Results in 5.89327 seconds Other interesting Feshpatents.com categories: Electronics: Semiconductor , Audio , Illumination , Connectors , Crypto , |
||
