US2375664A - Laundry sour - Google Patents

Description

Patented May 8, 1945 Adolph V. Kla-ncnik and Frank J. Klancnik, Chicago, Ill.-

No Drawing. Application October 10-, 1 942, v Serial No. 461,636

5 Claims. (01152-145) This invention relates to a sour and more particularly to a laundry sour used to neutralize excessive amounts of residual alkali in washing and rinsing waters.

Laundry sours as heretofore provided served to neutralize the residue alkali and soap in the washing and rinsing waters usually to an acid pH of 4.0 to 6.5. Their tendency was to decompose the soap and to go toward neutral and sometimes to the alkaline side upon drying, thus causing discoloration due to the heat upon ironing. Consequently, the effects of the tinting'solutio'ns, such as the well known bluings, were nullified and the finished fabrics acquired an undesirable brownish color.

An object of the present invention is to provide a highly improved laundry sour adapted to is sc -controlled that it will be and will be present in the finished goods.

vidinga sour that will drop the acid pH value slightly under 7.0, say, in the neighborhood of from 6.9' to 6.5, which is a very desirable range sary for the finished goods.

for tinting-and producing the appearance neces- This acid condition is maintained throughout the laundering and tinting operations and will not be lost by the heat upon ironing. The excessive acid condition heretofore encountered, and that at times showed a pH as low as 4.0, is avoided and a conchange the washing waters or solutions from .the e alkaline side to a slightly acid condition and maintain the same during rinsing and tinting operations and upon drying and ironing. It is known that the tinting solutions better perform their function in an acid bath and that the effects of tinting will be more satisfactory and a better appearance produced, particularly in the case of white linens, if the clothes will remain slightly acid after they are ironed; The present invention is accordingly directed to a laundry sour that will assure a slightly acid condition of thewashing and rinsing waters so that the tinting will take place in an acid bath, and further, that will assure that the clothes will remain slightly acid after they are ironed.

Although an excessive acid pH in the washing and rinsing water's is undesirable because it is destructive and tends to break down the fabric, it. was necessary heretofore to add an excessive amount of sour if a slight acid condition were to be maintained in the finished goods, due to the tendency of these prior art sours to go to neu-- tral and even tothe alkaline side upon drying. The amount of sour that had to be added to secure a slight acid condition of the finished goods depended of course upon the bicarbonate content of the water, andwhere this content was high, greater quantities of sour had to be used and sometimes to an extent that considerable damage would be caused to the finished goods. An excess acid condition of the washing and rinsing waters also caused an undesirable. heaviness orstiifness in the finished goods after ironing, due

to an apparent .filling action of the intersticesand possibly of the pores of the fabric. The

dition. assured that remains constant and produces efiicient results.

More specifically the invention is preferably directed to a laundry sour comprising a mixture employing, ammonium chloride as its base and a magnesium carbonate as a bufier for the base to prevent the ammonia from separating from the chloride. In .case the ammonium chloride tends to cake or lump, a small amount of starch may .be employed to produce a dusting eiiect upon the ammonium chloride. 'We' have found that if a small amount of acid, such as oxalic acid or a fluoride, is added to this mixture, the acid pH can be definitely controlled so that a pH slightly below 7.0 can be obtained and be held not only in the washing and rinsing waters but in the laundry sour disclosed herein produces a slight finished goods. With this slightly acid condition, the bluing dyes added to the bath will efiect an efiicient tinting action that produces. a desirable appearance of the finished goods.- We have found that discoloration is effectively eliminated and the fabric will be in a natural uniform state without the aforesaid stifiness orheaviness heretoiore experienced when anexcessive acid pH had to be used in the washing and rinsing waters to I secure a slight acidpHin the finished goods.

Specific examples of the laundry sour will be found in the use of a mixture consisting of 97.5%

. maintained throughout the laundering and tinting operations The acid pH that is producedwill not' be excessive and will not be harmful to the goods. One of the features of the invention is directed to pro-' washing waters and appear in the finished goods, a fluoride or oxalic acid may be added. The amount of acid to be added may vary, but we have found that anywhere between 2 to 10% will be satisfactory. Of the difierent fluorides that may be used, sodium silico fluoride, ammonium fluoride, ammonium silico fluoride ammonium acid fluoride and sodium acid fluoride are mentioned. desirable acid in the proportions that may be necessary, and consequently, we do not wish to be limited in. this respect.

While it may be desirable to add the percentage. of ammonium chloride mentioned because ood results have been obtained, it will be apparent that the scope of the invention extends to the use of varying amounts and that this percentagemay be changed within a considerable range. The same is true with the buffer and the cluster mentioned and also with respect to the time of buffer and duster used. We have found that these amounts depend somewhat upon the conditions at the time.

The results produced showed efficient'neutralizing of excessive residue alkali in the washing and rinsing waters and efflcient tinting in the It is intended to use in the mixture any apropos! items are intended to be defined and secured to us by the following claims.

We claim:

1. A laundry sour comprising a dry mixture containin about 97.5% of ammonium chloride and from 0.5% to 2.5% of magnesium carbonate.

2. A laundry sour comprising a dry mixture containing about 97.5 parts of ammonium chloride, 0.5 to 2.5 parts of magnesium carbonate, and from about 2 to 10 parts of a water-soluble acidreacting substance selected from the group consisting of the acid-reacting fluorides and oxalic acid.

3. A laundry sour composition comprising a dry mixture containing a major portion of ammonium chloride, a minor portion of magnesium carbonate in an amount sufiicientto prevent the development of excess acidity upon dispersion of the composition in water, and an amount of a Watersoluble acid-reacting compound selected from the group consisting of the acid-reacting fluorides and oxalic acid sufficient to impart to an aqueous dispersion of the composition a pH of about from tinting baths. Although a slight acid condit'on is produced, it will remain and cause the clothes to be also slightly acid after ironed in order to have the most favorable appearance when finished. A further advantage to be obtained resides in the fact that the materials mentioned are relatively inexpensive and may be easily obtained.

Without further elaboration, the foregoing willso fully explain the gist of my invention that others may, by applying current knowledge, readily adapt the same for use under varying con ditions of service, without eliminating certain features, which may properly be said to constitute the essential items of novelty involved, which 4. A laundry sour comprising a dry mixture containing a major portion of ammon.um chloride and a minor portion of magnesiumcarbonate, the latter in an amount sufficient to prevent the development of excess acidity upon a dispersion of the composition in water.

5. A laundry sour in dry form comprising a major portion of ammonium ch oride, a minor portion of magnesium carbonate in an amount sufficient to prevent development of excess acidity upon the dispersion of the composition in water. and suflicient starch adhering to the ammonium chloride to prevent the adhesion of the ammonium chloride particles to each other in the dry composition.

ADOLPH V. KLANCNIK. mANK J. ICLANCNIK.