Bridgestone has filed a patent for a multi-piece solid golf ball that aims to optimize deflections when subjected to specific loading. The ball is designed to achieve superior distance on full shots with a driver and irons. The patent specifies the composition and hardness relationships among the layers of the ball. GlobalData’s report on Bridgestone gives a 360-degree view of the company including its patenting strategy. Buy the report here.
According to GlobalData’s company profile on Bridgestone, anti-skid tyre treads was a key innovation area identified from patents. Bridgestone's grant share as of September 2023 was 35%. Grant share is based on the ratio of number of grants to total number of patents.
Multi-piece solid golf ball with optimized deflections and distance
A recently filed patent (Publication Number: US20230310947A1) describes a multi-piece solid golf ball with specific design features. The golf ball consists of a core, an envelope layer, an intermediate layer, and a cover. The core is made of one or more layers of a rubber composition, while the envelope layer, intermediate layer, and cover are each made of a single layer of resin material.
The patent claims that the hardness relationship among the layers must meet certain conditions. The material hardness of the cover must be greater than the material hardness of the intermediate layer, and the material hardness of the envelope layer must be equal to or greater than the surface hardness of the core. Additionally, the thickness of the envelope layer multiplied by the material hardness of the envelope layer must be greater than or equal to the thickness of the cover multiplied by the material hardness of the cover.
The patent also specifies a deflection requirement for the golf ball. When compressed under a final load of 1,275 N (130 kgf) from an initial load of 98 N (10 kgf), the deflection of the core minus the deflection of the ball must be 1.00 mm or more.
Furthermore, the patent includes additional conditions for the golf ball. The thickness of the envelope layer multiplied by the material hardness of the envelope layer must be greater than or equal to the thickness of the intermediate layer multiplied by the material hardness of the intermediate layer. The sum of the cover thickness and intermediate layer thickness must be less than or equal to the envelope layer thickness.
The patent also describes the composition of the resin material used in the envelope layer and intermediate layer. It consists of a base resin, an olefin-unsaturated carboxylic acid random copolymer or a metal ion neutralization product, blended with an olefin-unsaturated carboxylic acid-unsaturated carboxylic acid ester random terpolymer or a metal ion neutralization product. The resin material also includes a non-ionomeric thermoplastic elastomer, a fatty acid or fatty acid derivative, and a basic inorganic metal compound.
The patent further mentions that the layers of the golf ball must have a specific thickness relationship, and the core and the ball must have specific diameter ratios. Finally, the patent specifies a condition related to the volume and hardness of the core, envelope layer, and intermediate layer.
In summary, the patent describes a multi-piece solid golf ball with specific hardness relationships among the layers, deflection requirements, and composition specifications for the resin material. The patent also includes conditions for the thickness and diameter ratios of the ball.