Polyamide Polyolefin Golf Ball Core for Soft Feel

The patent applies local quality by creating distinct regions within the core with different material compositions and hardness levels. The multi-layer core structure features an inner core, intermediate layer, and outer core layer, each with specific ionomer content and hardness characteristics. This allows the ball to have a softer feel and better spin control in the regions that contact the clubface, while maintaining overall durability through the harder protective layers.

The patent uses composite materials by combining ionomer polymers with other polymers such as polyethylene, polypropylene, or elastomers in specific ratios. This creates a multi-phase composite material that balances the hard, durable characteristics of ionomer with the softer, more controllable characteristics of the other polymers, resolving the contradiction between durability and spin control.

The patent implements local quality by designing the core with varying hardness zones. The outer core layer or intermediate layer can be formulated with lower ionomer content or different polymer blends to provide a softer feel upon impact, while the inner core maintains higher hardness to generate sufficient initial velocity. This spatial variation in material properties allows simultaneous optimization of both speed and feel.

The patent applies parameter changes by adjusting the ionomer polymer content, molecular weight, and hardness parameters across different core layers. By controlling these parameters - specifically using ionomer content of 10-90% by weight in various layers and adjusting Shore Durometer hardness values - the patent achieves the desired balance between initial velocity generation and soft feel on contact.

The patent uses local quality by distributing ionomer content non-uniformly across the core structure. Certain layers or regions contain higher ionomer concentrations (up to 90% by weight) to provide toughness and durability, while other regions contain lower ionomer content (as low as 10% by weight) or incorporate softer polymers to maintain controllability. This spatial differentiation allows the ball to exhibit both high toughness and good control characteristics.

The patent employs composite materials by creating multi-phase blends within the core, combining ionomer polymers with other polymers such as polyethylene, polypropylene, or elastomers in controlled ratios. This composite approach allows the tough ionomer phase to provide durability while the other polymer phases contribute to softer feel and better control, effectively resolving the contradiction between toughness and controllability.