US2064285A - Leather cleaning composition - Google Patents

Description

Patented Dec. 15, 1936 2,064,285 LEATHER CLEANING CGMPGSI'IEQN No Drawing. Application November 5, 19%, Serial No. 751,577

2 Claims. (Cl. 8?-5) This invention relates in general to leather 8.3 gallons of a 48% solution of U. S. P. potascleansers and more particularly to a cleaner for sium hydroxide are mixed with 57 gallons of iron finished leather goods such as suede leather free oleic acid to form a soap containing an exjackets, cess of oleic acid. The soap is then added to 8'75 The cleaning of soiled finished leather particugallons of hydrocarbon solvent having the ML larly leather jackets has. in the past been a problowing characteristics:

lem with the dry cleaning industry owing to the wide variety of spots and types of dirt with Arqmatlc content l or mums 60% whichthe leather jackets became soiled Such Amhne 15 Distillation range 135 to 195 C.

10 substances as varnish, paint, blood, grease, milk et, cetera, often saturate the leather in places rendering their removal most difficult, even when prespotting with a strong solvent which often re- '70 gallons of dipentene and 12.5 gallons of secmoves also the dye in the leather. A common ondary butyl alcohol are added to complete the Flash point. (Tagliaube open cup) plus or minus 100 F. i

practice is to submit the leather to the usual composition. The excess amount of oleic acid,

dry cleaning treatment with a suitable hydrodipentene, and alcohol, in addition to adding decarbon solvent, frequently with a final operation sirable solvent qualities, aid in dissolving the poof scraping, e. g. with sandpaper, to remove spots tassium oleate in the solvent.

not taken out in dry cleaning. I From the standpoint of performance com- In the past, cleaned leather' jackets often plete solubility of the soap in the solvent is not emerged from the cleaning process with blue, essential, although where the product is to be m lavender, green or gray stains in them which stored mutual solubility of all the ingredients is cannot be removed with the usual solvents. desirable in order to prevent Stratification, and

It is an object of this invention to provide a. corrosion of metal containers.

9 leather cleanser which will readily remove or The purity of the oleic acid is of importance, 9 soften spots of foreign substances on the leather. for I have found that the colored streaks 'ap-'= A further object of the invention is to provide a pearing in dry cleaned leather goods are the leather cleanser which will not remove the dye result of reaction between chemicals remaining from the leather in appreciable quantities. A in the leather from the tanning process with further object is to provide a cleanser which will small amounts of iron salts so that as small a 0 not adversely affect cleaning solvent systems, percentage as .002% (as F6203) in theoleic acid into which some of the. cleanser is certain to will produce a discoloration of the cleaned pass. leather. Commercial shipments of white oleic Another object of this invention is to provide acid have contained iron in amounts varying a leather cleanser which will not produce 001- from 0.020.002% (as ream).

ored stains in the dry cleaned article. The fore- As a preliminary step in the manufacture of going objects and other which will be apparmy composition I remove the traces of iron soap cut, I prefer to accomplish with a product obfrom theoleic acid by treatment with a small tained by mixing a given amount of alkali with amount of aqueous tannic acid, after which the an excess of iron free oleic acid to form an oleate aqueous liquor containing the iron as tannate [m with some free oleic acid present. The resulting is drawn off and the purified oleic acid is water soap is then dissolved in a hydrocarbon solvent washed to remove the remaining tannic acid. having a relatively high percentage of aromat- -By this means I have been able to reduce the ics, or a chlorinated solvent such as carbon iron content of the oleic acid to such an extent $5 tetrachloride.

A small amountof pine oil, or pine oil derivaalthough it will of course be realized that it is tive such as dipcntene, or a low boiling alcohol preferable to remove all traces of iron. may be added to the mixture as an additional While it is preferable to use a solvent with as solvent. high an aromatic content as possible, any per- The novel features that I consider charactercentage of aromatics over 20% will serve. While 50 istic of my invention are set forth with particu- I prefer to use a. hydrocarbon fraction having larity in the appended claims. The invention, a high flash point, at the same time it is desirhowever, together with. advantages thereof will able to have a solvent .which has an end point be best understood from the following descripsuificiently low to permit. ready evaporation of tion of a specific example of my cleaner. the cleanser. It is obvious that other suitable that .my soap contains less than .001% iron, 45

solvents might have a boiling from that given in the example.

The preferred method of using the cleanser is as follows: the leather goods are run for a few minutes in a dry cleaning washer, containing one of the usual cleaning solvents in order to remove loose dirt. The solvent is then wrung out of the leather goods which are next soaked range different used as a soaking used as a prespotter or added to the cleaning 4 solvent.

My leather cleanser has been found to remove oil and grease spots and to loosen the gums and resins of many paints and varnishes as well as to remove blood, and water soluble spots produced by sugar solutions, jam, etc. My leather cleanser has been found more effective than when using the ingredients separately. example, while aqueous solutions can be used still! so that a supplemental treatment is necessary to restore the suppleness to the leather. 0n the other hand, by the use of petroleum products alone, blood more permanently. leather cleanser effectively loosens the blood spots so that they are readily removed in the usual dry cleaning or, in case of resistant paint spots, etc., by brushing, after application of the cleanser and prior to rinsing in solvent.

Another advantage of my cleanser as before stated is that the formation of colored patches in the leather is prevented.

Although I have described certain specific tannic acid embodiments of my invention, I am aware that modifications thereof are possible. While I have used my cleanser on leather understood that it may also be used as a cleanser for other materials.- The invention therefore is not to be restricted, except insofar as is necessary by the prior art and the appended claims.

I claim as my invention:

1. The process of preparing an improved leather cleaning composition comprising subjecting a substantially pure commercial oleic acid, which contains combined iron in a concentration sufficient to cause the discoloration of leather cleaned with a cleanser containing a dry-cleaning soap of said acid, to the chemical'action of under conditions to form iron tannate and to reduce the concentration of iron in said oleic acid to less than .001%, separating oleic acid containing less than .00l% iron from the iron tannate, saponifying the separated oleic acid to form a dry-cleaning soap, and mixing said soap with a dry-cleaning solvent. x

2. The process of preparing an improved leather cleaning composition comprising subjecting a substantially pure commercial oleic acid containing combined iron in a concentration of more than .00l% tothe chemical action of tannic acid under conditions to form iron tannate and to reduce the concentration of iron in said oleic acid to less than .001%, separating the treated oleic acid containing less than .001% iron from the iron tannate, saponifying the separated oleic acid to form a dry-cleaning soap, and mixing said soap with a dry cleaning solvent.

WALLACE J. YATES.

goods, it should be