A golf ball has a plurality of dimples 12 and a land 14 on a surface thereof. The golf ball further has a large number of minute projections 18 formed on surfaces of the dimples 12 and the land 14. The minute projections 18 are exposed on the surface of the golf ball. The surface of the golf ball has an arithmetic average height Sa of not less than 0.5 m and not greater than 30 m. The surface of the golf ball has a maximum height Sz of not less than 5 m and not greater than 200 m.

A coated golf ball includes a single or dual core and a cover layer formed from a thermoplastic polyurethane (TPU). The TPU cover preferably has a first polyurethane coating layer and a second polyurethane coating layer disposed about the first polyurethane coating layer. In a preferred embodiment, he first polyurethane coating layer includes unreacted isocyanate groups and has an isocyanate index of at least about 120. Preferably, the first polyurethane coating layer has an isocyanate index of at least about 150, more preferably, at least about 200, and most preferably at least about 250.

Golf ball incorporating polyurethane mixture having wt. % NCO content of 4-20 and including a prepolymer polyol portion comprised of trans--Farnesene diol(s) in an amount of about 3-70 wt. % of total weight of prepolymer. Trans--Farnesene diol may be 15 carbon, long chain, branched, unsaturated 3,4-vinyl-containing bio-hydrocarbon having the formula: ##STR00001## Prepolymer can include a 1:99 to 99:1 blend (wt. % ratio) of Trans--Farnesene diol(s) and polybutadiene-based polyol(s) in an amount of about 35-85 wt. %, along with about 15 wt. %-65 wt. % of diisocyanate(s). Curative may be combined with prepolymer in amount of about 3-25 wt. % of total weight of curative and prepolymer combined, and may be mixture of aromatic diamine(s) and white dispersion in a wt. % ratio of about 90:10 to 50:50, plus catalyst. Hardness of polyurethane mixture can be from 75. Shore A to 75 Shore D or a material hardness can be from about 40 Shore D to about 65 Shore D.

A rubber composition for golf balls includes (a) a base rubber, (b) a co-crosslinking agent which is an ,-unsaturated carboxylic acid and/or a metal salt thereof, (c) a crosslinking initiator, and (d) an alcohol having a value obtained by dividing the molecular weight of the alcohol by the number of hydroxyl groups thereon which is 70 or less. When the rubber composition is used in a golf ball having a core and a cover of one or more layers encasing the core, by setting the hardness difference in the core interior hardness profile to a large value while maintaining a desired core hardness, low spin properties can be manifested on golf ball shots, enabling the flight performance of the ball to be improved.

A golf ball has a large number of exposed portions 22 on a surface thereof. An average value Hav of heights H of these exposed portions 22 is not less than 0.5 m and not greater than 50 m. The surface of the golf ball has one or more first zones and one or more second zones. An average value Hav1 of the heights H of the exposed portions 22 on these first zones is higher than an average value Hav2 of the heights H of the exposed portions 22 on these second zones. Preferably, the average value Hav1 and the average value Hav2 satisfy the following mathematical formula.

3(Hav1Hav2)50

A golf ball comprising a core comprising an inner core center and an outer core layer disposed over the inner core center. The inner core center has a deflection of greater than 0.210 inch under a load of 100 kilograms, and the entire the core has a deflection ranging from 0.130 inch to 0.105 inch under a load of 100 kilograms. A mantle layer is disposed over the core and a cover is disposed over the mantle.

Multi-layered golf balls having a core, intermediate layer, and cover are provided. The ball includes a non-foamed inner core (center) made of a thermoplastic or thermoset composition such as polybutadiene rubber. An intermediate layer comprising a foamed composition, such as polyurethane foam, is disposed about the inner core. The foamed intermediate layer may have a specific gravity gradient within the layer, wherein the outer surface specific gravity is greater than the midpoint specific gravity. Ball constructions having two intermediate layers, wherein at least one layer is a foamed layer can be made. A cover having at least one layer is disposed about the intermediate layer.

A method of manufacturing golf balls having a core and a cover of at least one layer encasing the core includes the steps of producing a core by molding and vulcanizing a rubber composition containing (A) a base rubber, (B) an ,-unsaturated carboxylic acid and/or a metal salt thereof, and (C) an organic peroxide; and heat-treating the core for 1 to 24 hours at between 175 and 300 C. Golf balls which undergo little energy loss and have a high initial velocity can be obtained by this method.

Golf balls comprising a multi-layer core and a cover are disclosed. The multi-layer core comprises a center, an intermediate core layer, and an outer core layer. At least one layer of the multi-layer core is a high specific gravity layer.

Golf balls comprising a core having at least one layer and a cover having at least one layer are provided. At least one of the layers is made from a thermoplastic composition preferably comprising a telechelic ionomer derived from alkyl-cis-cyclooctene and cis-cyclooctene. The telechelic ionomer composition also may be used to form intermediate layers. Blends of telechelic ionomers and polybutadiene rubbers or ethylene acid copolymers can be prepared. The telechelic ionomer compositions can be used to make a cover layer having good impact durability and shear resistance and that also helps provide the ball with high resiliency.