GB2227671A

GB2227671A - Golf ball with outer covering layer

Info

Publication number: GB2227671A
Application number: GB8828512A
Authority: GB
Inventors: Michael Shaw; Brian Francis Machin
Original assignee: Dunlop Ltd
Current assignee: Dunlop Ltd
Priority date: 1988-12-07
Filing date: 1988-12-07
Publication date: 1990-08-08
Also published as: GB8828512D0; GB2227671B

Abstract

A moulded golf ball is provided with an outer covering layer (for example of a film) which is compatible, under moulding conditions, with the cover of the golf ball. The film is applied to the assembled golf ball cover and core, before completing the moulding process. The outer layer improves adhesion of paint or varnish and/or improves the reception of an identification mark or stamp. The film may, for example, comprise a biaxially-oriented film or co-extruded film laminate.

Description

GOLF BALL WITH OUTER COVERING LAYER This invention relates to a method of making a golf ball with an outer overing layer and to golf balls obtained thereby.

It is often desirable to provide a golf ball with an outer layer, for example, to improve adhesion of a paint or varnish, to improve the reception of an identification mark or stamp, or to improve the appearance and/or the durability of the finished ball.

Hitherto, this has-been achieved by a dipping, spraying or painting process after moulding of the golf ball.

It has now been found that golf balls can be provided with an outer covering layer during the process of moulding the cover member around the core member of the ball.

Accordingly, the present invention provides a method of making a golf ball by moulding a cover member around a core member in which, prior to moulding, the cover member is assembled around the core member and the assembly is provided with an outer layer of a material compatible, under the moulding conditions, with the material of the cover member whereby, on completion of the moulding, the outer layer extends over substantially the whole outer surface of theball.

The present invention also provides a golf ball made by the method described in the immediately-preceding paragraph.

Suitably, the outer layer may comprise a film, for example, a biaxially-oriented film.

Alternatively, the outer layer may comprise a co-extruded film laminate, preferably a laminate in which individual laminae have different melting-points or softening-points.

For example, the laminate may include at least one layer of a hot-melt adhesive.

The outer layer may, for example, comprise: (i) one or more ionic copolymers (e.g. those available under the Registered Trade Mark SURLYN); (ii) one or more polyamides (e.g. those available under the Registered Trade Mark NYLON); (iii) polyvinyl chloride: (iv) polyethylene; (v) polyurethane; (vi) One or more epoxy-based or acrylate-based materials; or any compatible combination of (i) to (vi) above.

Where the outer layer is a film, it may conveniently be formed around the ball by shrink -wrapping before moulding.

Preferably, the cover member and outer layer are moulded around the core member by a compression -moulding process.

The present invention will be illustrated, merely by way of example, as follows A solid core member, together with a cover member containing a mixture of ionic copolymers and a shrink -wrappable film containing at least one ionic copolymer layer, were assembled and placed in a mould. Moulding was carried out at a temperature of 160 to unite the film and the cover member to each other and the cover member to the core member and to form, in accordance with the configuration of the mould cavity, a corresponding dimple pattern on the outermost surface of the moulded golf ball.

Potential advantages of golf balls made according to the present invention include, but are not limited to, the following (a) The degree of hardness of the outer film can be selected so as to influence or control the spin and aerodynamic behaviour of the ball; (b) The outer film can be selected so as to improve the "feel" of the ball when played by a golfer; (c) Proper selection of the outer film can improve durability of the ball and reduce the amount of "finishing" required on completion of the moulding process.

Claims

CLAIMS:

1. A method of making a golf ball by moulding a cover member around a core member in which, prior to moulding, the cover member is assembled around the core member and the assembly is provided with an outer layer of a material compatible, under the moulding conditions, with the material of the cover member whereby, on completion of the moulding, the outer layer extends over substantially the whole outer surface of the ball.

2. A method according~to Claim 1, in which the outer layer comprises a film.

3. A method according to Claim 2, in which the outer layer comprises a biaxially-oriented film.

4. A method according to Claim 2 or 3, in which the outer layer comprises a co-extruded film laminate.

5. A method according to Claim 4, in which individual laminae have different melting-points or softening-points.

6. A method according to Claim 4 or 5, in which the laminate includes at least one layer of a hot-melt adhesive.

7. A method according to any one of the preceding claims, in which the outer layer comprises one or more ionic copolymers, one or more polyamides, polyvinyl chloride, polyethylene, polyurethane, one or more epoxy-based materials, one or more acrylate-based materials or any combination thereof.

8. A method according to any one of Claims 2 to 7 in which the outer layer is formed around the ball by shrink-wrapping.

9. A method according to any one of the preceding claims in which the outer layer and cover member are moulded around the core member by a compression-moulding process.

10. A golf ball made by the method of any one of the preceding claims.

11. A golf ball, substantially as hereinbefore described with reference to the Example.