US3445564A - Rapidly drying lower aliphatic alcohol-acetone sanitizing composition and method - Google Patents

Description

3,445,564 RAPIDLY DRYING LOWER ALIPHATIC ALCOHOL- No Drawing. Filed Jan. 4, 1965, Ser. No. 428,007 Int. Cl. A61k 27/00, 9/00 U.S. Cl. 424-45 6 Claims ABSTRACT OF THE DISCLOSURE A method, compositions and articles for sanitizing public or communal facilities prior to individual use are described. The method consists of applying a thin layer of a rapidly drying liquid germicidal composition to a surface, such as a toilet seat, and drying the surface prior to use. The rapidly drying germidical compositions consist essentially of a lower aliphatic alcohol and at least about of a volatilizing agent therefor, such as acetone. The articles of the invention are dispensing units containing the germicidal compositions, including aerosol and other spray units and other dispensing devices capable of applying a thin layer of the germicidal compositions to a surface to be sanitized.

The present invention relates to a sanitizing method and to articles useful therein and, more particularly, to a method and articles adapted for use by an individual member of the public at large to sanitize or disinfect public or communal facilities prior to use by the individual.

Many people are reluctant, for sanitary or aesthetic reasons, to use facilities or objects of personal use previously employed by others. For this reason various expedients have been suggested for achieving sanitary use public facilities such at toilet seats. For example, devices have been developed for exposing toilet seats to germicidal ultraviolet radiation after use thus assuring subsequent users of the sanitary condition of the toilet seat. Another common expedient is to provide a supply of disposable single-use paper toilet seat covers at a location adjacent to the toilet seat. While both of these expedients are in current use to some extent, they are not universally available and, therefore, fail to provide a satisfactory solution to the problem.

Therefore, it is a primary object of the invention to provides convenient means for individuals to sanitize public facilities such as toilet seats and other articles and surfaces prior to personal use.

It is another object of the invention to provide articles adapted to be carried customarily by an individual for use in sanitizing public facilities such as toilet seats and other articles or surfaces prior to use.

It is still another object of the invention to provide a purse or pocke stize aerosol dispenser containing a rapidly drying liquid germicidal composition.

The above and other objects of the invention which will be apparent from the detailed description herein are achieved by providing as novel articles, conveniently carried purse or pocket size dispensers containing a rapidly drying liquid germicidal composition consisting essentially of a lower aliphatic alcohol and a volatilizing agent. The method of the invention comprises applying a rapidly drying germicidal composition to a surface to be sanitized such as a toilet seat, for example, .and then drying the treated surface prior to personal use.

More specifically, the method of the invention is carried out by applying a rapidly drying liquid germicide to the surface to be treated by any suitable technique such as Patented May 20, 1969 spraying, roller coating, brushing, wiping, sprinkling or the like. The spray technique is preferred because of its convenience and efliciency. Any type of spray applicator may be employed although it is, of course, preferred to use the simplest and least cumbersome equipment possible. For this reason, aerosol spray dispensers are especially suitable although conventional atomizers are also convenient to use.

Other useful germicidal applicators include cans, jars or tubes closed at one end by means of a spherical applicator mounted for rotation. When the applicator is rolled over a surface liquid is transferred from the container to the surface. The rapidly rying liquid germicide may also be conveniently applied by means of a saturated pad of cellulosic or other material which is individually packaged in a. sealed metal foil container. The foil container is adapted to be opened by tearing so that the gerimicide-moistened pad can be removed and wiped over the surface of the toilet seat. Still another suitable application technique is to sprinkle the toilet seat, for example, with germicide from a suitable container followed by wiping the seat with toilet tissue to spread the germicide evenly and thinly over the surface of the seat. Innumerable other suitable application techniques will suggest themselves to those skilled in the art.

The second step of the method of the invention, i.e. drying of the liquid germicide on the treated surface, is greatly facilitated by the use of a germicidal composition compounded for spontaneous and rapid evaporation. Suitable compositions for this purpose will be described below. Drying of the treated surface may also be facilitated by minimizing the amount of germicide applied in step one and by achieving uniform distribution of the germicide over the surface to be treated. The thickness of the layer of applied germicide may be reduced, thus hastening drying, by wiping the treated surface with toilet tissue or any other suitable material. Wiping of the surface also promotes uniformity of coverage and serves to remove soil and any excess germicide applied in step one. Any

, other suitable technique for drying the treated surface may also be employed.

The fast drying liquid germicidal compositions employed according to the present invention in sanitizing toilet seats and other articles and surfaces consist essentially of a lower aliphatic alcohol and a volatilizing agent. Although other optional materials may also be included such as additional antibacterial agents, perfume, propellants and the like.

Suitable lower aliphatic alcohols for use in the germicidal compositions include methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol and the butyl alcohols. Ethyl alcohol, while otherwise highly satisfactory, has the disadvantage of being high in cost. The butyl alcohols, while useful, are less satisfactory because of their higher molecular weight and consequent higher boiling points and lower volatility which tends to increase the drying time of the germicidal compositions. For these reasons isopropyl alcohol is the material of choice since it has excellent germicidal activity, is low in cost, readily available, and sufficiently volatile to give a satisfactory drying rate when blended with suitable proportions of a volatilizing agent.

Inasmuch as the lower aliphatic alcohols are not sufficiently volatile to afford usefully short drying times for practical purposes in the method and articles of the present invention it is necessary to include a volatilizing agent in the germicidal composition. Suitable materials for this purpose include but are not limited to volatile organic liquids miscible with lower aliphatic alcohols including the lower molecular Weight alkanes, ketones, ethers and alkyl halides, for example. More specifically suitable volatilizing agents include the pentanes and hexanes, acetone, methyl ethyl ketone, dimethyl ether, methyl ethyl ether, methyl chloride, ethyl chloride, the propyl chlorides, methyl bromide, ethyl bromide and the propyl bromides among others Which will be readily apparent to those skilled in the art.

The proportion of volatilizing agent to lower aliphatic alcohol in the rapidly drying germicidal compositions employed in the invention may vary widely depending upon a number of factors, which include among others, the volatility of the alcohol employed, the volatility of the volatilizing agent, the desired drying rate of the germicidal composition, the amount of germicidal agent applied to the surface to be treated and the method of application of the germicide, not to mention the prevailing conditions of temperature and relative humidity under which the product is to be employed. In general, however, it can be stated that the germicidal compositions must contain at least about 5% of volatilizing agent by volume based upon to the total volume of volatilizing agent and aliphatic alcohol in the composition. Although less than 5% of volatilizing agent may be employed with advantage in some cases, e.g. as little as 1% or even less, the reduction in drying rate achieved at such levels is generally insufficient for practical purposes with most compositions. At the other end of the range, as much as about 80% or more volatilizing agent by volume may be employed based upon the volume of the alcohol-volatilizing agent mixture. It is not generally necessary, however, to employ such large volumes of volatilizing agent.

to achieve a satisfactory drying rate. Moreover, it is generally desirable to minimize the amount of volatilizing agent employed in order to avoid unnecessary dilution of the germicidal alcohol although this is not a serious consideration where the volatilizing agent is also active against germs as has been found to be the case with acetone. Therefore, it is preferred to employ about to 40% of volatilizing agent by volume based on the total volume of the alcohol-volatilizing agent mixture, depending upon the various factors noted above. Of course, relatively large amounts of volatilizing agent are required to achieve a given drying rate with the higher molecular weight alcohols and with methods of application which are less efiicient in providing a uniform layer of minimal thickness on the surface to be sanitized. Conversely smaller amounts of volatilizing agent are required with the more volatile lower molecular weight alcohols and when a minimal amount of germicidal composition is applied to the surface to be sanitized in a uniform layer of minimal thickness.

More specifically, an excellent and novel germicidal composition for use in the present invention consists essentially of an isopropyl alcohol-acetone mixture, the acetone volatilizing agent being present in about 15 to 40% and preferably about by volume based upon the volume of the alcohol-acetone mixture.

As noted above, the amount of volatilizing agent employed depends upon the drying rate desired. Although suitable drying rates for a thin layer of germicidal composition on a surface to be sanitized may vary widely it is obviously desirable to maximize this rate in order to minimize waiting time before the sanitized surface may be used. Therefore, it is generally desirable to employ a germicidal composition having a drying rate such that a thin uniform layer spread on a surface will dry spontaneously in about 1 minute and preferably in less than secs. Compositions having a drying rate such that a thin layer would require several minutes or even more to dry may also be used, however, particularly if they are intended for only occasional use or for use to sanitize surfaces which are not expected to be put to immediate use.

Where inherently less rapidly drying compositions are employed, the time required to achieve a dry sanitized surface may be materially shortened by wiping the wetted surface with a suitable material which is preferably but Example I A typical rapidly drying liquid germicidal composition is made by mixing the following substances:

Amount per Percent by volume based Component unit charge, on total volume or ml. alcohol-acetone mixture Isopropyl alcohol 22. 5 Acetone 7. 5 25 Perfume 06 0. 2

Mixing may be accomplished by any suitable conventional means, no problem being encountered since the acetone and alcohol are completely miscible. The unit charge of germicidal liquid obtained in this way is then packaged in a conventional aerosol container of suitable size by well known procedures with the addition of about 46% by weight of Freon 12 (CCl F as a propellant, based upon the weight of the total alcohol-acetone, Freon perfume composition.

When an aerosol container charged with the above germicidal composition and propellant is used to spray a surface to be sanitized such as a toilet seat, a thin uniform layer of germicide may be obtained which dries spontaneously by evaporation in less than 1 minute. If the sprayed surface is wiped with toilet paper immediately after spraying the drying process is accelerated so that the treated surface dries completely in a few seconds.

The aerosol germicidal spray dispenser of Example I when used as described therein provides a convenient and expeditious means of sanitizing any desired surface not attacked by alcohol or acetone such as the seat of a public toilet.

The novel rapidly drying liquid germicidal composition of Example I may also be applied to the surface to be treated by other suitable techniques in carrying out the method of the invention, such as by the use of an atomizer, sprinkler, applicator pad or the like.

The preferred method of applying the germicidal composition, however, is by the use of a pressurized spray technique. Any suitable propellant may be used for the germicidal composition including the preferred Freon type fiuorinated chlorohydrocarbons, of which representative members are monochlorodifluoromethane (CHClFg), dichlorodifl-uoromethane (CCl F monochlorodifiuoroethane (CH CClF octafiuorocyclobutane (C F dichlorotetrafiuoroethane (CC1F CC1F dichlorofluoromethane (CHCl F), trichlorofluoromethane (CC1 F); chlorinated hydrocarbons such as ethyl chloride and methylene chloride among others; alkanes such as propane and butane among others; other volatile organic compounds such as dimethyl ether; and compressed gases such as nitrous oxide, carbon dioxide, nitrogen and argon, as well as compatible mixtures of the above and other propellants. The chemical identity of the propellant employed is not critical in the method and articles of the present invention with the exception that the propellant must not have a sufficiently deleterious effect on the germicidal composition employed to destroy its utility as a germicide.

The propellant may be soluble or insoluble in the germicidal composition. The ratio of the propellant to germicidal composition may vary widely and will depend upon many factors including the composition of the germicidal mixture, the physical characteristics of the propellant, the

size and geometry of the aerosol or other spray device and the degree to which it is filled, all as well known in the art.

It has been found, however, that it is generally necessary to employ sufficient propellant to produce an internal pressure in the container of at least about 15 pounds per square inch gauge (p.s.i.g.) in order to achieve satisfactory application of the germicide to a surface to be sanitized. Any reasonable pressure above 15 p.s.i.g. may be employed, limited only by the bursting strength of the container and safe use of the spray. It has been found, however, that pressures of about 15 to 70 psig are suitable and entirely adequate for most purposes.

dispenser of Example I and allowed to stand for a short period and then each slide was aseptically transferred to 50 mls. of Letheen broth subculture media. Thirty minutes after the initial transfer, the slides were re-transferred to a fresh subculture.

The primary and secondary subcultures of Salmonella choleraesuis and Staphylococcus aureus were incubated for 48 hours at 37 C. and the primary and secondary subcultures of Trichophyton interdigita'le were incubated for ten days at 28 C., after which they were examined for growth or no growth of the test organism. The results of these tests are summarized in Table I below.

TABLE I Spray T Dist Subculture series No.

me ance, Sample sec: inches Organism 1 2 3 4 5 6 7 8 9 10 3 4 Disinfectant aerosol spray of ExampleI g i ggggggfgggggf i gk 3 3 Staphylococcus aureus 2 2 g }Trzch0ph1 ttminterdzgztale. 1.507- 0 g }Salmonella choleraesmr 2.00 n 125% 3 3 }Staphylococcusaureus....

Inasmuch as it is a primary object of the invention to provide a conveniently carried germicide dispenser the container must be compact in size. This influences the choice of a desirable propellant in view of Boyles law which states that at a constant temperature, the pressure of a given quantity of gas is inversely proportional to the volume it occupies. Inasmuch as the temperature and volume of the propellant gas are constant for a dispenser of any given size, reduction of the amount of gas in the container by spraying causes a rapid drop in the gas pressure. Therefore, when gases such as nitrogen, carbon dioxide, argon and the like are used in small aerosol containers, the pressure drops so rapidly on use that it may fall below p.s.i.g. before the container has been emptied of germicide. The Freon type liquid fiuorinated chlorohydrocarbon propellants are preferred, therefore, since they maintain a relatively constant pressure above the germicide in the container as long as any of the propellant remains in the liquid phase. This is due to the fact that the Freon type propellants and other volatile liquid propellants vaporize to replace vapor lost in spraying thus repeatedly restoring the vapor pressure in the container as long as the supply of liquid propellant lasts.

The aerosol spray product of Example I was tested against the representative organisms T richophyton interdigitale, a fungus, and Salmonella choleraesuis and Staphylococcus aureus, bacteria. The germicidal activity of the isopropyl alcohol-acetone mixture was compared to that of phenol according to the method described in the Journal of the A.O.A.C., vol. 44, No. 1, pages 137-138 (1961). Ninety (90) one inch glass slides were sterilized. Under aseptic conditions, 0.01 ml. of a separate 48 hour culture of each of the above organisms were spread over 30 of the sterile slides which were then dried for 30 minutes at 37 C. After drying, of the slides in each group were sprayed with dilutions of phenol for 3 seconds at a distance of 3 inches as follows:

Trichophyton interdigitale-Ten (l0) slides were sprayed with a 1.50% solution of phenol and ten 10) slides were sprayed with a 1.00% solution.

Salmonella choleraesuisTen (l0) slides were sprayed with a 1.50% solution of phenol and ten (10) slides were sprayed with a .50% solution.

Staphylococcus aureus-Ten (l0) slides were sprayed with a 2.00% solution of phenol and ten (10) slides were sprayed with a 1.25% solution.

The remaining 10 slides in each group were sprayed at a distance of 4 inches for 3 seconds with the aerosol spray It is apparent from the data in Table I above that the germicidal aerosol spray and sanitizing method of Example I are highly effective as illustrated by their bactericidal and fungicidal activity against representative organisms.

It will be apparent from the foregoing that the method and articles of the present invention provide for the first time convenient means for an individual to sanitize a toilet seat or other article or surface prior to personal use.

The novel germicidal compositions of the present invention consisting essentially of isopropyl alcohol and at least about 5% by volume of acetone, have unexpected utility as sanitizing agents. This is due to the fact that although the antiseptic properties of isopropyl alcohol are Well known, the germicidal activity of acetone and its mixtures with isopropyl alcohol had not been discovered heretofore. The antibacterial and antifungal activity of isopropyl alcohol-acetone mixtures containing 25% to or more acetone by volume is especially surprising since as noted above the teachings of the prior art would suggest that dilution of the isopropyl alcohol to this extent would materially reduce germicidal activity. As may be seen from the data in Table I above, this is not a serious problem when the diluent is acetone as shown by the excellent germicidal activity of the 25 acetone mixture against representative organisms.

It should be noted, furthermore, that the isopropylalcohol-acetone mixtures of the present invention differ from many germicides commonly used heretofore in that they are essentially nonaqueous in character. This is important, although not absolutely essential, in the method of the present invention since water tends to delay drying of the germicide when applied to a surface to be sanitized. Although essentially nonaqueous, small amounts of water may be tolerated in the isopropyl alcohol-acetone compositions. Therefore, the readily available constant boiling isopropyl alcohol-water mixture which contains about 13.3 water may be employed in formulating the alcoholacetone germicidal compositions since the proportion of water thus derived does not seriously retard the drying rate of the compositions.

Although the isopropyl alcohol-acetone compositions of the present invention have excellent germicidal activity in that bacteria, fungi and other lower organisms are killed on contact within seconds, if desired, additional antibacterial, antifungal or other active ingredients may be incorporated in these or other rapidly drying liquid germicidal compositions useful in the invention. Suitable germi cidal additives include the well known anti-bacterial quaternary ammonium compounds such as cetyl pyridinium chloride and benzalkonium chloride and other known germicidal agents such as hexachlorophene, for example.

Any suitable perfume may be employed in quantities sufiicient to give the germicide a pleasant odor and/ or to mask unpleasant odors in the environment of use.

The preferred germicidal compositions of the invention consist predominantly of lower aliphatic alcohol and volatilizing agent, i.e. these ingredients make up about 85 to 100% of the liquid content of the compositions exclusive of any liquid propellant employed. As noted above, however, the compositions may also contain water or other usual impurities associated with the alcohol or volatilizing agent, added germicidal agents, perfume etc. If desired the germicidal compositions may be diluted with inert liquids such as water or hydrocarbon solvents miscible with the active alcohol and volatilizing agent. Up to 90% of such inert liquids may be employed if desired but in this case the amount of volatilizing agent recited above should be based on the total volume of liquid including the inert liquid rather than on the volume of the alcoholvolatilizing mixture.

I claim:

1. An aerosol spray dispensing unit containing a rapid ly drying liquid germicidal composition and a propellant therefor, said unit being adapted to apply a thin uniform layer of said germicidal composition to a surface to be sanitized, said liquid germicidal composition consisting of a lower alkyl alcohol havng 1 to 4 carbon atoms and from about 5 to 80 percent by volume of acetone as the active ingredients, said acetone also acting as a volatilizing agent for said composition.

2. An aerosol spray dispensing unit according to claim 1, wherein said liquid germicidal composition contains about to 40 percent acetone by volume.

3. An aerosol spray dispensing unit according to claim 1, wherein said liquid germicidal composition contains about 25 percent acetone by volume.

4. A method for sanitizing a surface prior to personal use which comprises applying to said surface a thin uniform layer of the rapidly drying liquid germicidal composition of claim 1 and drying said surface to provide a dry sanitary surface for personal use.

5. A rapidly drying liquid germicidal composition consisting of isopropyl alcohol, about 25 percent by volume of acetone and an antibacterial substance selected from the group consisting of hexachlorophene and a quaternary ammonium compound.

6. An aerosol spray dispensing unit containing a rapidly drying liquid germicidal composition and a propellant therefor, said unit being adapted to apply a thin uniform layer of said germicidal composition to a surface to be sanitized, said liquid germicidal composition consisting of a lower alkyl alcohol having 1 to 4 carbon atoms, from 5 to percent by volume of acetone and an antibacterial substance selected from the group consisting of hexachlorophene and a quaternary ammonium compound.

References Cited OTHER REFERENCES Reddish: Antiseptics, Disinfectants, Fungicides, and Chemical and Physical Sterilization, Lea & Febiger, Philadelphia (1954), pp. 298301 and 3043 14.

Shephard: Aerosols-Science and Technology, Interscience Publishers, New York (1961), pp. 203, 221, 228, 233, 344-346, 464 and 514.

The Canadian Patent Otfice Record, Nov. 18, 1941, p. 3238, No. 400, 785.

ALBERT T. MEYERS, Primary Examiner.

V. C. CLARKE, Assistant Examiner.

U.S. Cl. X.R.