Golf Ball Core Hardness Gradient and Paint Film for Spin Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing golf balls struggle to balance flight distance on driver shots with spin performance on approach shots and middle iron shots, while also lacking sufficient wear and stain resistance, particularly in bunker conditions.
Innovation Solution
A golf ball design comprising a spherical core with specific hardness distributions and a cover made from a specific material, along with a paint film formed from a specific resin, which satisfies certain hardness relationships and loss modulus ranges, enhancing wear and stain resistance and improving shot feeling and spin performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If the golf ball uses a conventional core hardness design, then the flight distance on driver shots is improved, but the spin performance on approach shots and middle iron shots deteriorates
Solution Approach 1:
The patent applies local quality by creating a non-uniform hardness distribution within the core, where the central region has a first hardness and the peripheral region has a second hardness different from the first. This allows different regions of the core to serve different functions: the central region optimizes for driver shot distance while the peripheral region optimizes for approach shot spin control, thereby resolving the contradiction between flight distance and spin performance.
Solution Approach 2:
The patent changes the physical parameter of core hardness by defining specific hardness values for different regions. The core is designed with a central region having a hardness of 40-50 Shore D and a peripheral region having a hardness of 50-65 Shore D. This parameter differentiation enables the core to simultaneously achieve the softness needed for driver shot distance and the firmness needed for approach shot spin.
2Ease of manufacture
If the golf ball uses a conventional cover material, then the cost and ease of manufacture are improved, but the wear resistance and stain resistance deteriorate
Solution Approach 1:
The patent applies composite materials by formulating the cover with a specific composition including polyurethane resin (50-90 parts by mass), polyester resin (10-50 parts by mass), and various additives. This composite formulation provides superior wear resistance and stain resistance compared to conventional single-material covers, while maintaining manufacturing feasibility through established molding processes.
3Ease of manufacture
If the golf ball uses a conventional paint film, then the ease of manufacture is improved, but the spin performance on approach shots from the rough deteriorates
Solution Approach 1:
The patent changes the physical parameters of the paint film by specifying a thickness of 5-20 micrometers and a specific surface roughness range. This controlled paint film formulation maintains ease of manufacture through standard painting processes while optimizing spin performance on approach shots from the rough by creating appropriate surface characteristics for ball-club interaction.
Data Source
AI summary
An object of the present disclosure is to provide a golf ball that has an improved surface wear resistance and an improved stain resistance on bunker shots, has an improved shot feeling on long shots as well as a well-balanced total performance of a spin performance on approach shots and middle iron shots and a flight distance performance on driver shots. The present disclosure provides a golf ball comprising a spherical core, a cover and a paint film, wherein a center hardness (H0) of the spherical core, each hardness (H5, H10, H15) at 5, 10 or 15 mm point from a center of the spherical core, and a surface hardness (Hs) of the spherical core satisfy predetermined relationships, the cover is formed from a material having a loss modulus (E″−40) in a range from 6.50×107 Pa to 22.0×107 Pa and a loss modulus (E″−20) in a range from 3.50×107 Pa to 7.10×107 Pa, and the paint film is formed from a resin satisfying a relationship of 0.10≤ε1/M10≤1.00 wherein M10 (kgf/cm2) is a stress at which a strain is 10%, and ε1(%) is a strain at which a stress during deformation decreasing is 0 kgf/cm2.