US 2544732 A
Description (OCR text may contain errors)
iatented Mar. 13, 1 951 OFFICE METHOD FOR RENDERING A FABRIC GERMICIDAL Isaac L. Shechmeister, United States Navy,
No Drawing. Application September 27, 1945, Serial No. 619,005
3Claims. (c1.117 139.5)
(Granted under the act of March 3, 1883, as
amended April 30, 1928; 370 0. G. 757) This invention relates to the treatment of fabrics, and it is particularly concerned with the impregnation of fabrics with an oil to reduce the incidence of airborne infections.
It has been established that the incidence of infections caused by bacteria carried in the atmosphere may be sharply reduced in hospitals and other institutions by the use of blankets and other fabrics which have been impregnated with one or more of various oils. Fabrics so treated entrap the dust particles which carry many bacteria, and to a large extent prevent their reentry into the atmosphere even when the fabric is shaken. However, the known methods for providing such oil impregnated fabrics suffer certain disadvantages.
For example, it would be desirable if the physical action of the oil in retaining the air-, or dust-, borne bacteria were to be re-enforced by a certain amount of bactericidal action as well.
Further, the known treatments of the type discussed above have been deficient in that oil impregnated fabrics have not been able to retain a substantial proportion of the impregnating agent when they are washed. In other words, the bond hitherto obtained between the fabric and the oil has not been a firm one.
Still another disadvantage of the known methods for impregnating fabrics with oils relates to the fact that no one solution may be used for treating both wool and cotton materials.
It is therefore an'object of this invention to provide a method which is useful for impregnating fabrics, including both wool and cotton fabrics, with an oleaginous material.
A more particular object of this invention is to accomplishthe foregoing object while at the same time establishing a firm bond between the fabric and the oleaginous impregnating agent.
Still another object of the invention is to provide an oleaginous solution, having bactericidal, or germicidal properties, which is useful in carrying out the foregoing objects.
v I have discovered that the foregoing objects may be accomplished through use of an emulsion comprising water, oil, and a non-ionic emulsifying agent, or, more properly, a non-ionic surfaceactive agent as emulsifier to which is added a substance known as a cationic detergent or agent or, more properly, cationic surface-active agent. This latter material, on being introduced into the emulsion, serves to produce a positive charge on each of the oil droplets present therein and these positively charged droplets are firmly taken up by 2 the negatively charged fabric which is under treatment.
The oil used comprises any high grade mineral oil, those normally used in carrying out my invention conforming to USP specifications.
The emulsifying agents useful in carrying out this invention are well known compounds, and a Wide variety thereof are available. However, those which are satisfactory for the purpose described herein are non-ionic surface-active agents. Two representative compounds of this class are polyethylene-glycol-monoiso-octyl-phenyl ether, and the polyoxyalkylene ether of partial oleic acid ester.
The cationic surface-active agent is so called from that fact that it is responsible for imparting a positive charge to the various oil droplets comprising the oil phase of the emulsion. While a variety of compounds exist which are capable of such action,.those which I prefer to use are those which possess germicidal qualities and which are non-toxic on application to the skin. The quaternary ammonium salts such as benzalkonium chloride (high molecular alkyl-dimethyl-benzyl-ammonium chloride); paratertiary-octylphenyl-diethoxy-dimethyl-benzyl-ammonium chloride; monium chloride; cetyl-dimethyl-benzyl-ammonium chloride; and the lauryl-ethyl-methyl-amide of trimethyl-ammonium chloride, have proven to be of particular value. Likewise, good results have also been obtained with the compounds lauryl-pyridinium-iodide and the 'lauryl ester of glycine hydrochloride.
It is believed that the nature of the invention will be best understood by a consideration of the following paragraphs which set forth the general method for compounding and using the fabric impregnating, oleaginous solution described herein.
The normal procedure is to place an amount of water in a suitable apparatus, as a washing machine, sufficient to thoroughly wet the fabric. Normally about three to four gallons of water are used for a woolen blanket of average size and weight. To the water is then added the fabric to be treated. The machine is then put in motion for a period of time sufficient to evenly distribute the water in the fabric.
A quantity of an oil emulsion made up of the oil and the emulsifying agent is then added. This emulsion comprises about 2 to 15 per cent by weight of the emulsifying agent (a preferred range is about 5 to 10 per cent by weight) and the balance oil. The amount of emulsion used is lauryl-dimethyl-benzyl-am- 'suflicient that the oil fraction thereof is from about /2 to about 5 per cent by weight of the dry weight of the fabric, though a preferred range is about 1 to3-per eent. The use-of largenquantities of theemulsicnintroduces-a fire hazard,and is therefore to be avoided.
The machine is then again rotated to an extent suificient to secure an even dispersion of the solution, or emulsion, throughout 'the fabric. 1 The cationic surface-active agent is then added. .TIhe amount thereof to be used willpreferably be varied depending on the nature'arid'weight'oi the fabric under treatment, the percentages of this ingredient which follow being given :in terms of the weight of the dry fabric. undyed wool, about 0.05 to about 0.5, andpreferably about 0.2 to about 0.3, per cent ofthe c'ationic surface-active agent are usedin 'thef'ma chine. For dyed woolen fabrics, this amour-it is increased to about 0.35 to about 1.35 per cent, and preferably'to about 0.5 to about 1.0 per cent. For either plain or dyed cotton goods, about ;05 to about -0.5:-per cent, 1 and preferably'about 0.1 -to about 0.3 per cent, of the cationic surface-active agent are employed. The' cationicsurface-active agent isnormally added in the form of a wateror other solution, but the ranges given above -.for this, ingredient are calculated on a dry weight basis-and, as stated above, in terms of the per cent byweight of theweightof dry-fabric in the machine. Obvious calculations will -.-provide.-.the amount of-any :given solution of the cationic surface-active -agent to be employed.
After the various ingredients have-all been added, the rotation :of the machine continued untilan appreciable clearing of the emulsionvis noted; Such-aclearing isevidence that substantially-all-ofthe chin the emulsion has been taken up by the fabric-in the machine. The-machine is-thendrained of the remaining watery fluid and the fabric is given: the conventional finishing treatment.
Fabrics treatedin accordance .with-the inventiondescribed herein possess the ability .to retain and destroy-most of the saprophytic and pathogenic micro-organisms deposited in the :fabricithrou'gh dus't,'human upper respiratory tract, and other air-borne, channels. "Upon shakinglthe treated'fabiic, only about one-tenth of the dust particles and bacteria entrapped in'the fabric arebrought'ba'ckinto'the atmosphere as comparedwitli'the'amount of dust and bacteria released'by a similar s'haking'o'f non-treated fabrics. Thefore'going'properties are retained by a treated fabric for a period of at'least "six 'm'onths'per single treatment.
' One washing of fabrics treated in accordance with the method described above removes about 40 per cent of the oil from cottons, and about25 per cent of the'oil from woolens. Thereforeyin the re-treatment of the washed fabric,""the amounts of the various ingredients used should becorrespondingly less than the amounts specifled. in 'the'foregoi-ng paragraphs whichrelated to the treatment of'fabrics having no appreciable oilcontent.
While this invention is described in terms of particular ingredients, and ranges thereof, to'be used, it is obvious that many-modificationsand variations in the natureand proportions of the In the case. hi
ingredients may be made without departing from the spirit and scope of the invention, and only such limitations should be imposed as are indicated-inthe appended claims.
The inventionidescrihed .hereinzmay be manufactured and used by or for the Government of ..the United States of America for governmental .purposes without the payment of any royalties ithereon ortherefjor.
.1. A method of, rendering a fabric germicidal comprising the steps of: intimately contacting the fabric with a mineral oil in water emulsion stabilizedaby. anon-ionic surface-active emulsifying agent selected from the group consisting .of polyethylene glycol monoiso octyl-phenylether and polyoxyalkylene ether of a partial oleic zaci'd ester; said emulsion used to contact said fa bric containingan amount of mineral oil equivalent to from about 0.5 to about 5 percent by weight based-on atheudry: fabric and an, amount of non-ionic:surfaceractivezemulsifying agentequivalenttoabout. 2 to. ,15 percent by weight based on the blendofaoiland emulsifying agent; adding to said-emulsioninrcontact with the fabric a cationic .surface-active :germicida1 detergent selected from the group consist ng Of-benzalkoniumchloride, -,paratertiar-y-octylphenyl-diethoxy-dim eth- .yl-benzyl-ammonium chloride, lauryl-dimethylbenzyl-ammonium chloride, cetyledimethyl-benzyl-ammonium chloride, lauryl-ethyl-methylamide'of trimethyl-ammonium chloride, laurylpyridinium-iodide, zandrlaurylsesteroi glycine hydrochloridasaid cationicsurface-active germicidaldetergenhbeingadded;in an amount equiv-' alent to from about .05 to 1.35 percent by weight based :onrthe dry-fabric anddryi-ng ,to-remove the water, phaseof the emulsion from. the treated fabric.
2. The methodof claim 1- wherein thefabricis woolen.
-3. Themethod ofclaim 1 wherein the fabric is cotton. I
. ISAAC L..SHECHMEISTER.
REFERENCES CITED The following :references are 2of record in the file :of this patent:
i UNI'IED STATES PATENTS Number 'Name Date 1,327,904 Carter Jan. 13, 1920 1,915,891 Kagi June27, 1933 23151864 "Muller Oct. 1; 1935 2,015,865 iMuller Oct; 1, 1935 2,054,257 Hueter Sept. 15, 1936 2143986 Kling Jam-'17, 1 939 2,286,824 McNally et al June -16, 1-942 1332;817 Srnith Get-26,1943 2-,37-13933 -Steinbock 1 "'Mar.-20,"19l5 23398-5295 Epstein-etaL 1--Apr-.' 9,1946 2,398,-296 .Epstein' etal. :Apr. 9, 1946 FOREIGN PATENTS Number Country Date 1358,202 Great Britainl Oct. 3, 1931 l OTHER REFERENCES