A system for measuring golf ball trajectory characteristics is disclosed. The system includes artificial grass with a launch location for a golf ball and a plurality of wide-angle distance optical sensors mechanically connected to the artificial grass positioned such that a field of measurement of each wide-angle distance optical sensors intersects. The system also includes a central processing unit connected to the wide-angle distance optical sensors, the central processing unit configured to collect distance measurements from the wide-angle distance optical sensors and to determine a velocity of a trajectory of the golf ball from the launch location to the intersection of the field of measurement of each wide-angle distance optical sensors given a distance between the plurality of the wide-angle distance optical sensors, a distance between the plurality of the wide-angle distance optical sensors and the launch location, and the distance measurements from the plurality of the wide-angle distance optical sensors. Once the velocity of the trajectory of the golf ball is determined, the central processing unit transmits the velocity to a display.

Golf balls having covers made of thermoplastic polyurethane compositions are provided. Multi-piece golf balls can be made. Polyurethane primer coatings and polyurethane top-coatings are applied to the thermoplastic polyurethane cover. Different coating methods can be used. Isocyanate-rich and polyol-rich polyurethane coatings can be applied. In one embodiment, the golf ball can be treated with a multi-functional isocyanate prior to applying the coatings. The polyurethane cover composition and surface coatings can further include catalysts, ultraviolet (UV)—light stabilizers, and other additives. Heat is used to cure the coatings. The coating methods have many benefits and the finished balls have good physical properties.

A putting training device having the same size and feel of a standard golf ball yet adapted to exaggeratedly deviate from an expected line of action when mishit relative to a predefined line of action. The putting training device may have one or more inner cavities wherein an inner spherical object rolls along a tracked, concentric first curvature when the putting training device is struck with a putter accurately along the predefined line of action, and wherein the inner spherical object moves to a side portion of the one or more cavities upon the putting training device being mishit, resulting in the exaggerated deviation that affords the user a visual feedback they can learn from and recalibrate their future putts to.

A golf ball having a single-layer rubber core, a single-layer resin cover and one intermediate layer therebetween satisfies the following conditions:

(Shore C hardness at surface of intermediate layer-encased sphere)>(Shore C hardness at ball surface),

(Atti compression of core)/(Shore C hardness at core surface−Shore C hardness at core center)≤1.1, and

(Shore C hardness at surface of intermediate layer-encased sphere)/{(Shore C hardness at core surface−Shore C hardness at core center)×intermediate layer thickness (mm)}≤2.7.

This ball has a superior distance performance on full shots with an iron and a high spin performance in the short game, imparts a very soft feel and possesses an excellent durability to cracking on repeated impact. The ball is intended to satisfy the needs of skilled amateur golfers who handle iron shots skillfully.

Golf balls including a plurality of radar detectable marks disposed on any single layer or among two or more layers thereof are provided. When all of the radar detectable marks present on any layer of the ball are radially projected onto the outer surface of the ball, the resulting overall pattern of projected radar detectable marks includes a series of three or marks located on a 1.5 mm wide great circle band on the outer surface of the ball.

An object of the present disclosure is to provide a golf ball having excellent durability and flight distance and good shot feeling for an average golfer who hits a golf ball at a slow head speed. The present disclosure provides a golf ball comprising a spherical core and at least two cover layers covering the spherical core, wherein a difference between a core surface crosslinking density and a core center crosslinking density is more than 1.0×10.sup.2 mol/m.sup.3 and less than 9.0×10.sup.2 mol/m.sup.3, a hardness difference between a core surface hardness Cs (Shore C hardness) and a core center hardness Co (Shore C hardness) is 13.0 or more and 30.0 or less, a compression deformation amount of the core when applying a load from an initial load of 98 N to a final load of 1275 N to the core is 3.8 mm or more, and the at least two cover layers include a first cover layer and a second cover layer positioned closer to the spherical core than the first cover layer, an average hardness Dave=(Ti×Hi+To×Ho)/(Ti+To) of the first cover layer and the second cover layer is 55 or more, where To (mm) is a thickness of the first cover layer, Ho (Shore D) is a slab hardness of the first cover layer, Ti (mm) is a thickness of the second cover layer, and Hi (Shore D) is a slab hardness of the second cover layer.

A golf ball with improved durability is disclosed herein. The golf ball has a core comprising a polybutadiene material and methyl methacrylate, butadiene, styrene (MBS) with a weight percentage of MBS ranging from 0.5 to 5 weight percent of the core.

A resin composition for golf balls includes (a) an acid-containing copolymer having an amount of acid constituent per 100 wt % of the sum of monomer units in the copolymer that is from 1 to 30 wt %, and (b) an amine-containing polymer having a branched structure. The resin composition imparts golf balls with an excellent rebound resilience and also confers an outstanding durability to repeated impact and an outstanding scuff resistance, making it particularly useful as a cover material in golf balls.

In a golf ball having a core, envelope layer, intermediate layer and cover, the (core diameter)/(ball diameter) value falls within a particular range, the core has a specific hardness profile, the intermediate layer is formed primarily of an ionomer resin material including a high-acid ionomer resin, and the Shore C hardness relationships among the core center and surface hardnesses and the surface hardnesses of the envelope layer-encased sphere, intermediate layer-encased sphere and ball satisfy the following conditions: (1) core surface hardness<surface hardness of envelope layer-encased sphere<surface hardness of intermediate layer-encased sphere>ball surface hardness, (2) (surface hardness of envelope layer-encased sphere)−(core center hardness)≥28. Also, the intermediate layer and cover have respective thicknesses which satisfy the condition: (3) cover thickness<intermediate layer thickness. This ball enables mid-level and skilled amateur golfers to achieve superior distances on driver shots and on iron shots, and moreover has a soil yet good feel at impact.

In a golf ball for professional golfers and skilled amateurs which has a single-layer core, a cover and at least one intermediate layer therebetween, the sphere obtained by encasing the core with the intermediate layer (intermediate layer-encased sphere) and the ball have a surface hardness relationship which satisfies the condition:

(surface hardness of intermediate layer-encased sphere)>(surface hardness of ball).

The core has a diameter of from 35.5 to 39.5 mm and a distinctive hardness profile that satisfies specific conditions. The ball is endowed with both an excellent flight performance and excellent durability to repeated impact.