GB409214A - Improvements in or relating to methods for the production of rubber threads or strands - Google Patents

Abstract

409,214. Producing rubber thread from aqueous dispersions by dipping processes. McKAY, R. F., Fort Dunlop, Birmingham.-(International Latex Processes, Ltd.; 10, Lefebvre Street, St. Peter's Port, Guernsey.) Oct. 19, 1933, No. 28907. [Classes 70 and 87 (ii).] A method for the production of rubber thread from aqueous dispersions of rubber comprises separating a coagulated deposit of rubber produced direct from the dispersion into continuous thread by forming the coagulated deposit on a backing surface or former provided with a continuous groove having comparatively sharp edges between the convolutions thereof. The rubber may be deposited on the former by spraying, dipping, electrodeposition or other methods. As shown, apparatus for carrying out the method comprises a hollow cylindrical drum 10 having a continuous helical groove 11<a>, 11<b> on its outer and inner surfaces and sharp webs 12<a>, 12b between. This drum is suspended in a tank of latex by means of a hanger 15 having arms engaging in holes 16 in the end of the drum. There are holes 16 in the other end also. The drum is heated and dipped one or more times, being reversed and dried, with its deposit, between each dipping. After the last dipping it is dried and vulcanized. The deposit shrinks taut into the grooves, and in the case of light thread may be peeled easily off the drum, tearing apart at the sharp edge. With heavier thread, the drum is passed between two rollers, the lower roller being urged upward by treadle mechanism ; the pressure thus exerted on the deposit causes it to be cut at the sharp edges. For removing the thread the drum may be placed on a rotating chuck 21, the thread being wound onto reels 22, 23, the thread from the inner drum surface being guided through a loop 24. Specification 404,219 is referred to.