US2238850A - Mildewproofing and mothproofing treatment - Google Patents

Description

Patented Apr. 15, 1941 Martinlmthermamflyattsviilalld.

No Drawing.

November 23, 1938 Serial No. 242,124

4 Claims. 21-4) (Granted under the act of March. 3,

amended Ap l 30, 1928; 3'10 0. G. 157) This application is made under the act of March 3, 1883, as amended by the act of April 30, 1928, and the invention herein described and claimed, if patented, may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment to me of any royalty thereon.

This invention relates to mildewproofing of cellulose fabrics which are used in contiguity with rubber, such as cotton have lined with rubber, beltings, raincoats, rubberized shower curtains, rubber elasticized fabrics, and so forth. 7

This invention also relates to a combination of mildewproofing and mothprooflng for plant and animal fibre fabrics subject to the destructive action of fungi or insect larvae, such as wool, cotton, silk, mohair, and so forth.

precipitant, such as the chloride, which solution preferably contains a wetting agent, such as sodium lauryl sulphate, for example. The fabric is then washed. If desired, it may also be treated with a solution to precipitate the wetting agent. When using sodium lauryl sulphate as the wetting agent, a solution of a potassium salt may be used for this purpose. The fabric is then dried. By treating the fabric, before the first drying step in the above-described method is completed, to obtain maximum absorbency, with a solution of cadmium silicofluoride both mildewproofing and mothproofing is efiected and the remaining steps in the process may be omitted, since this solution precipitates the cadmium soap in the fabric. The fabric being somewhat damp,

7 it absorbs sufhcient cadmium fluosilicate solution One of theobjects of this invention is-to provide mildewprooiing means which are colorless and which willnot be readily removed by the ordinary so-called dry cleaning solvents or by water.

Heretofore, copper has been the most common mildewprooflng metal, but it is unsatisfactory when used in rubberized fabrics because it induces changes in the rubber component and also the copper is absorbed by the rubberwhich destroys its mildewproofing action. covered that cadmium has no injurious efiect I have diswhatever upon rubber, and that it is approximateiy twice as effective as copper in inhibiting growthactivity of organisms in cellulose.

I have also found that the common fatty acid snaps of cadmium suchas the oleate, palmitate, and steal-ate are practically insoluble in such solvents as carbon tetrachloride, gasoline, Stoddards solvent, and solvent naphtha. This is not true with respect to the non-fatty acid soaps, such as the resinate which-is very soluble in these solvents. For this reason, fabrics treated with the fatty acid soaps of cadmium may be dry cleaned, whereas the non-fatty acid soaps merflngitmaofacadmimnraltasa to precipitate the soap compound, leaving a residue of cadmium soap and alkali fluosilicate in the fabric. Fluosilicates are of value for mothproofing, and the waterproofing effect of the cadmium soap prevents easy removal of the residual water-soluble cadmium and alkali fluosilicateexcept by prolonged exposure to water.

The cadmium soap may also be introduced into the fibrous material by making use of certain mixed solvents to dissolve the soap and carry it into and through the fibrous material. For ex ample, the cadmium soap can be dissolved in a hot solution of a solvent consisting of two parts benzene, one part acetone, and one part methanol by volume. Mixed solvents, such as this one, especially when warm would retain enough cadmium soap in solution to permit the introduction of the soap into the material to be treated by wetting it with the solution and then drying the fabric.

Cadmium fluosilicate may also be used by itself to effect a combination of mildewprooflng and mothprooflng. Being soluble in water, but not in organic solvents, it may be employed in the'home totemporarily protect washable garments which may be stored. Such garments can be'treated by simply immersing them in the cadmium fluosilicate solution and then permitting the solvent to evaporate. So-called dry cleaning would not affect the fabric treated in this manner. A one-tenth of one percent solution of cadmium fluosilicat will normally introduce a suflicient protective quantity in the fabric after the fabrlc'is wetted with it and squeezed, wrung, or centrifuged. Ordinarily, five-hundredths of one per cent by weight of elemental cadmium and an equal amount of the fluosilicate (Bill's) radical will give satisfactory protection.

Having thus described my invention, 1 claim:.

1. An article of manufacture comprising a rubberized cellulose fabric impregnated with a' mildewproofing agent compatible with rubber, said agent containing cadmium palmitate as its essential active ingredient.

4. An article of manufacture comprising a rubberized cellulose fabric impregnated with a mildewprooflng agent compatible with rubber, said agent containing cadmium stearate as its essential active ingredient.