GB1147642A - Improvements relating to washing of textile fibres and materials - Google Patents

Abstract

1,147,642. Washing textiles. J. STONE & CO. (DEPTFORD) Ltd. 4 April, 1966 [22 April, 1965], No. 17020/65. Headings D1L and D1P. Textile articles, fabrics or fibres, e.g. of wool, are washed by subjecting them to the action of a surface-active washing agent applied to it in a liquid medium in one stage of the process and thereafter to the separate action of a washing liquor applied in another stage thereof, the ratio of the level of mechanical energy with which the washing liquor is applied to that with which the surface-active washing agent is applied being not less than 100 to 1, measured in units of energy per unit of area of material processed, and the ratio of the concentration by weight of surface-active substance in the washing agent to that of active substance in the washing liquor being greater than 50 to 1. The energy with which the surface-active washing agent is applied may be less than 1.85 x 10<SP>-6</SP> joules per square cm and that with which the washing liquor is applied more than 185 x 10<SP>-6</SP> joules per square cm. The active substance in the washing agent may be in such a concentration that the agent has a detergency effect equivalent to an aqueous solution of orthodox high-titre soap in a concentration of 0.25-5 parts by weight of active fatty acid soap in 100 parts of solution, and the active substance in the washing liquor may be in such a concentration that the liquor has a detergency effect equivalent to such a solution of less than 0.01 parts by weight in 100 parts of solution. The surface active washing agent may be a detergent or soap containing alkali, e.g. sodium metasilicate, caustic soda or trisodium phosphate, and a soil-suspending agent, e.g. polyvinyl pyrrolidone, sodium carboxymethyl cellulose or sodium carboxymethyl starch. In Fig. 1 separate articles to be washed are passed through the machine between an upper belt 10 and lower belt 11 both of net-like structure driven be tween A and B by pairs of rolls 16, 17 from an electric motor 19 through chains and sprockets 20 loaded against each other by pressure applying means, e.g. cylinders or springs 18. A solution of surface active washing agent supplied to tank 21 by pipe and level controller 22 is passed by pump 23 through filter 24 and control valve at 25 adjustable from remote-control panel 28 to manifold 26 fitted with nozzles 27 and sprayed across the full width of the articles, excess washing agent being squeezed out of the articles at H and collected in tank 21 for recirculation. Washing liquor is taken from the bottom of tank 50 containing heating means, e.g. steam oil 51, by which the 'liquor is kept at a predetermined temperature controlled by temperature-sensitive valve 52, by pump 53 and passed through filter 54 having a discharge 81 for separated dirt to manifolds 55 and 56 with nozzles 57 and distributed across the full width of the belts, excess washing liquor being squeezed out of the articles at I and collected in tank 50. Liquor is removed from the surface through drain 59 and from the bottom through drain 60, fresh liquor being supplied to tank 50 through inlet 61 its alkalinity being controlled 'by means of a valve actuated by an alkalinity detector 63. The articles are rinsed at stages E and F by passage through tanks 66 and 67 containing rinse liquors, fresh water fed in through pipe 72 flowing through the machine in a direction counter to the movement of belts 10 and 11 into section E and thence into the washing stages. The apparatus may be modified by applying the solution of the surface active washing agent at C by passing the articles through a tank containing the solution, by directing the solution from manifold 26 on to the surface of a roll which spreads the solution evenly over the articles or by passing the articles between a pair of rolls controllably loaded one against the other their axes in a common plane substantially departing from the vertical and the space between the upper surfaces of the two rolls being controllably flooded with the solution. Means may be provided so that the solution of the washing agent is applied only when an article is passing the point of application. In addition to or instead of spraying the articles with the washing liquor agitation may be produced by means of beater bars, the action of which may be augmented or complemented by energy produced by an ultrasonic generator. When treating continuous or semi-continuous lengths of fabrics or textile materials the belts 10 and 11 need not be used.