REMOVAL OF STAINS

Evening Star, Issue 20443, 26 March 1930, Page 13

REMOVAL OF STAINS

The following article aims at giving some, indication of the chemical theory of stain, removing, together with a classification of the, various types of stain and the chemical employed in each case. The easiest, commonest, and safest method is to employ a substance in which the staining agent is easily soluble, and which has no deleterious action on cither the colour or texture of the stained fabric. \ second method-rone moro generally used for cleaning an entire article—is to incorporate in the fabric an inert powder of such a degree of fineness that the stain substance is absorbed on tofts free surfaces, the resulting physical mixture being removed by hard brushing or beating. A combination of the above two is sometimes used, as for example, the employment of benzine and light magnesium carbonate in the cleaning of white fur. A third method, used only in what one might term desperate cases, is the employment of an active chemical such as a bleaching agent or mineral acid, which reacts in such a way as to remove the colour of the offending substance by chemical action. This method can generally be used for white fabrics, but may harm delicate fibres such as those oi : wool and silk, ft is obvious that 'whatever chemical is used it should have -no action on eithc. the dye or tijxtnre of the material to bo treated. Secondly, it should be as volatile as possible, or at any' rate if not volatile should be capable of complete removal leavfng neither colour nor odour behind Thirdly, it should bo non-poisonous, non-infhjmmable, and capable of.easy application and manipulation in the hands of ordinary people. GENERAL PRINCIPLES OF STAIN REMOVAL. 1. Treat immediately if circumstances allow. 2. Whenever possible employ organic solvents, as these seldom affect the dye iind have no deleterious action on the fabric. 3! Always try the simplest method first. 4. Whenever a strongly reacting substance has been used, such as blcacning agent or acid, thoroughly wash out all traces with cold water. 5. When convenient, stretch the fabric to bo treated over a bowl, or between concentric hoops such as are used for embroider^. C. Use as little solvent as is practicable, because very mobile liquids aro apt to spread rapidly on the material, leaving an area lighter in colour than the original. . 7. Rub dry with a clean cloth, rubbing from the outside inwards, in order to minimise the. risk.-of leaving a well-defined edge to the portion that has been treated. 8. Remember always in treating stains with substances other than harml:cs organic solvents that strong acids have an injurious effect on vegetable fibres, such as cotton, flax, and artificial silk, whereas alkaline solutions (soda, etc.), injure animal fibres, especially woollen articles. 9. Always experiment beforehand on an unimportant piece of the material, i.c., with a part of a garment that does not show, or an odd piece of material. Tho most common chemicals em ployed and the pros and cons of -ach are given below. ' ORGANIC SOLVENTS. Benzine, petrol, alcohol (methylated spirits), turpentine, acetone, amyl acetate, carbon tetrachloride. Benzine and petrol, while excellent solvents* have one-point against them, and that is their escessi- inflammability Petrol again, if not a high grade spirit, may often contain ’-races of liquids of higher boiling noinvs which leave oily stains in the clotn, and have n very disagreeable odour duo to their naphthalic origin. Alcohol, acetone, and amyl aceiale aro used only in certain cases, as specified below. For general oily stains caused by lubricating oil, grease, tar, greasy foods, etc., a liquid known as carbon tetrachloride has excellent solvent properties, is not too disagreeable, is quite volatile, has no harmful effects, and above all is non-inflammable. It is 1 also quite easy to obtain and is reasonably cheap. A tabulated and fairly comprehensive list of what to use for tho most u»ual stains is given below. It gives the most commonly occurring ruins, and the simplest method of removing them, using only those reagents to be found’' in any well-equipped house. TREATMENT OF STAINED WOOL, COTTON, AND LINEN. Blood,—Solution of common salt in water, or plain water followed by solution of soap and methylated spirits. Enamel.—Carbon tetrachloride (except in cases where the original enamel smells of peardrops, or is known lo be a cellulose paint, in which case use amyl acetate or acetone). Fruit, Tea, Coffee, Wine, Beer.— Water, followed with hydrogen peroxide or warm borax solution. On coloured materials use hydrogen peroxide when colour is fast to this reagent, otherwise try water followed by methylated spirits and soap. _ Foods (most). —Water (no soap),'or if of a greasy nature use a grease solvent such as carbon tetrachloride. ,

Grease, Wax, Oil.—Carbon tetrachloride. Iron Mould.—Salts of lemon, oxalic or citric acid solution. lodine.—Solution of “.hypo” in water. Writing Ink. —Oxalic or citric acid. I’aint.—Carbon tetrachloride. ' Sealing Was.—Methylated spirits. Sugar, Glue, Etc.—Water. Starch (from food such as potatoes). —Water. Slight Scorch. —Hydrogen peroxide. Varnish (oil). —Treat as paint. Varnish (shellac). —Mixture of carbon tetrachloride and methylated spirits.