GB549297A - Improvements in or relating to stiffeners for shoes and the manufacture thereof - Google Patents

Abstract

549,297. Shoe stiffeners. BRITISH UNITED SHOE MACHINERY CO., Ltd., HILL, M. G., and COOPER, C. A. May 10, 1941, No. 6071. Class 140] In the manufacture of shoe stiffeners such as toe puffs comprising blanks of fibrous material such as swansdown cloth charged with a solution of a stiffening substance such as nitrocellulose and intended to be stored before use in a limp condition and after insertion in the shoe to undergo hardening after evaporation of the solvent the stiffening substance in solution is caused to undergo gelling at the time of manufacture of the stiffener at least at part of the stiffener to prevent seepage of the stiffening substance during storing rom one part of the stiffener to another, for example from a more heavily to'a less heavily stiffened part, by treatment effective to produce such gelling without diminution in the ratio of solvent to stiffening substance. For effecting such gelling of nitrocellulose dope the most satisfactory treatment consists in subjecting it to the action of, borax which may be dusted in powdered form on to the swansdown layer before or after the dope is applied thereto or the borax may be included in the adhesive used for uniting the swansdown layer and a crinkled paper layer on one side of 'it or the grease-proof paper layer for the other side of swansdown layer may be treated with borax solution and dried before use. Other borates or substances such as ammonia or derivatives thereof such as hexamethylene tetramine may be used as the gelling agent. Specification 487,159, [Group VII], is referred to.