GB417268A - Improvements in and relating to brushes for toilet and other purposes - Google Patents

Abstract

417,268. Brushes moulding plastic substances. PEARSON, M., 59, New Oxford Street, London. April 8, 1933, No. 10610. [Class 19.] Toilet and like brushes have their bristles firmly mounted in a flexible foundation of rubber or like elastic material by moulding and vulcanizing thereto a rubber backing over the straight projecting bristle ends. A sheet of rubber a is laid on a perforated plate band pierced by pins, not shown, passing through the perforations. The plate b is then reversed and bristles are fed through the perforations by means of funnel-shaped holes g in a plate f so that projecting ends e can be arranged all at the same level. The projecting ends may be dipped in a mixture of toughened rubber and a solvent with or without vulcanizing material and/or an activating substance. After being subjected to heat and pressure, the rubber material approximates to ebonite. The parts are then reversed from the position of Fig. 2, and a plate h, Fig. 3, is applied to the plate b with holes k slightly larger than the corresponding bristle ends. By pressing the plates h, b together, the sheet a is nipped and the material is expanded into each hole k around the bristle bunch. The sheet a is set by partial vulcanizing. The plate h is removed and replaced by a rim plate h<1>, Fig. 4, and a mixture or solution is poured round the bristle knots. The free ends of the bristles are supported by a plate l. Excess solution on the inner ends of the bristles is drained off and the rest allowed to become tacky. The whole block with the bristle knots held by the sheet a is then laid upon or within a hot vulcanizing contact dry press to render the bristle knots into a hard substance resembling ebonite while the rubber sheet owing to distance does not become over vulcanized. The rubber back proper m, Fig. 7, is then moulded over the bristle knots, being placed plastic on a tray n and heated to a lower temperature than that for forming the bristle knots with which it becomes fused.