GB666468A - Improvements in tennis and like inflated balls and method of making same - Google Patents

Abstract

666,468. Balls for games. DUNLOP RUBBER CO., Ltd., ANDERSON, J., and GOY, R. S. Oct. 16, 1950 [Nov. 30, 1949], No. 30693/49. Class 132 (ii). A method of making a textile covered ball e.g. a tennis ball comprises covering an inflated core 4 with a single thickness of composite yarn made up of a central thread 2 and a helical winding of wool 3 or feltable fibres, effecting adhesion of the yarn to the core and raising and felting the covering on the core to form a felted surface 6. The core 4 is first covered with an adhesive layer 5 and then wound with the yarn from pole to pole. The core is then heated in a mould to effect adhesion of the cover and melt the central thread 2 of cellulose acetate. The yarn is then raised by a wire brush or in a tumbler having razor blades set therein and the cover is felted in known manner. The ball is washed and treated with polymethyl methacrylate and given a final moulding, the mould marks being removed by steam. In modifications, each hemisphere of the core may be covered by a separate length of yarn or four square panels of yarn may be used; the central thread may be made of sodium alginate, which is dissolved during felting, or of wool; before application to the core, the yarn may be wound on a cylinder, subjected under steaming to end pressure to give it a square cross-section and coated on one face with adhesive.