GB935001A - Improvements in or relating to the stiffening of shoes - Google Patents

Abstract

935,001. Toe and counter stiffeners. BRITISH UNITED SHOE MACHINERY CO. Ltd. Jan. 22, 1960 [Oct. 25, 1958; June 23, 1959], Nos. 34214/58 and 21426/59. Class 17 (2). [Also in Group VIII] A shoe stiffener blank comprises a fibrous base loaded with a composition comprising a thermoplastic synthetic resinous material, the composition being in such a condition that the blank after being submitted to a temperature of 100‹ C. or less and then cooled will be substantially stiffer. In making the blank a woven cotton cloth was passed through a bath containing polystyrene, a plasticizer, e.g. dibutyl phthalate and water, and possibly a rosinderived resin or a coconut shell flow dispersion, led between stripper rolls and through a drying chamber at a temperature below the softening point of the composition after drying. The composition then became deposited in the form of individual particles sintered together at their point of contact. The material was then calendered to a uniform gauge, cut up to provide stiffener blanks, and the marginal portions of the blanks were skived. The dried impregnant was conveniently present in an amount by weight at least equal to the weight of the fibrous base. The stiffener blanks ware then suitable for use as heat-activated blanks and when sufficient heat is supplied to the blanks the sintered particles of the polystyrene composition become fused and form a continuous film, and thus on cooling are much stiffer. The material may be coated on one side with an adhesive which is non-tacky at room temperature, but becomes tacky when heated, and on the other side by a neoprene adhesive suitable for binding flock to the material.