GB693619A - Improvements in or relating to the treatment of flexible materials with powder, granu - Google Patents

Abstract

693,619. Powdering flexible materials. TOOTAL BROADHURST LEE CO., Ltd. Feb. 27, 1951 [Feb. 1, 1950; Feb. 3, 1950], Nos. 2561/50 and 570/53, (the second Provisional Specification being divided out of the first Provisional Specification). Class 42 (i). A method of treating flexible materials with powder, granular matter or the like comprises passing the material along a predetermined path and applying the powder or the like thereto during such passage, and subsequently moving the material through the same path in the same direction, except that, during its second passage, the material is moved out of the said path and returned thereto through a bight which by-passes a portion of the path, and the powder is removed, or largely removed, from the material whilst passing through the bight. The materials treated may be knitted or woven fabrics in the length, or articles of woven or knitted textile yarns, or paper or flexible non- fibrous material such as flexible film. Articles such as wearing apparel are preferably secured to a length of flexible backing or conveying material, as by stitching. The powder may be applied by passing the material 1 from a roll 2 over a feed roller 3, beneath a bar or roller 4, which can be moved to alternative positions 5a, 5b, over a scrimp bar or roller 7, beneath a hopper 8, and over a roller 13, the material being wound or batched at 14. The hopper 8 may be provided with a mechanical or electromagnetic agitator 9, and with a rotary agitator 10 for the contained powder. Two or more hoppers, which may or may not be vibrated in synchronism, may be arranged in series. The powdered material, after a period of storage if required, is replaced at 2, and passed through the same path, except that the roller 4 is in the position 5b, which brings the material into the path of a rotating beater 16, which may be a rotary brush or a cage or drum fitted with transverse bars. The machine may be enclosed in a casing 18, from which the liberated powder may be removed through a discharge connection 20, and recovered by filtration or electrostatic precipitation. The application and removal of the powder to and from the material may be assisted by electrostatic means. Besides heating and brushing, the powder may be removed by suction or blowing, or both, or by passage through a bath of suitable liquid at the bottom of the bight, or by a combination of such treatments. The process may be applied to the treatment of fabrics containing wool with bleaching powder or mixtures containing this, in order to reduce their tendency to felt. Specification 654,739, [Group IV (c)], is referred to.