Title:
STABLE LIQUID DETERGENT CONCENTRATES CONTAINING ACTIVE OXYGEN
United States Patent 3852210
Abstract:
A stable liquid concentrate comprises about 0.1-50% of an active oxygen yielding compound, about 0.5-50% of a sulfobetaine or betaine surfactant, about 1-50% of a nonionic polyoxyethylene-polyoxypropylene block copolymer surfactant, and 10-80% water. The concentrate exhibits a loss of active oxygen of as little as 6.7% after 675 days and has utility as a bleaching and cleaning composition. The composition can be diluted with pure or ordinary tap water.
Application Number:
05/279801
Publication Date:
12/03/1974
Filing Date:
08/11/1972
View Patent Images:
Export Citation:
Assignee:
Flow Pharmaceuticals, Inc. (Palo Alto, CA)
Primary Class:
Other Classes:
514/715, 510/132, 510/303, 510/131, 252/186.260, 252/186.290
International Classes:
C07C409/00; C11D1/722; C11D1/94; C11D3/39; C11D1/88; C11D7/54
Field of Search:
252/95,102,100,103,106,107
Primary Examiner:
Weinblatt, Mayer
Attorney, Agent or Firm:
Finnegan, Henderson, Farabow & Garrett
Claims:
What is claimed is
1. A stable liquid concentrate composition consisting essentially of:
2. The composition of claim 1 wherein the active oxygen yielding compound is hydrogen peroxide.
3. The composition of claim 2 wherein the concentration of hydrogen peroxide is from about 0.5% to about 10%.
4. The composition according to claim 1 wherein the active oxygen-containing compound is selected from the group consisting of urea peroxide, benzoyl peroxide and hydrogen peroxide.
5. The composition according to claim 1 including 0.01 - 10% of a water soluble quaternary ammonium surface active agent.
6. The composition according to claim 1 including a complex-forming compound selected from the group consisting of ethylene-diaminetetraacetic acid, diethylenetriaminepentaacetic acid, and their water-soluble salts.
7. The composition according to claim 1 including acetanilid.
8. The composition of claim 1 including 0.01 - 10% of a water soluble quaternary ammonium surface-active and a complex-forming compound selected from the group consisting of ethylene-diaminetetraacetic acid, diethylenetriaminepentaacetic acid, and their water-soluble salts.
9. The composition according to claim 1 wherein the concentration of the active oxygen yielding compound is from about 0.5% to about 10%.
10. A stable liquid concentrate consisting essentially of:
11. The composition of claim 2 wherein the zwitterionic detergent is dodecyl sulfobetaine.
12. The composition according to claim 5 wherein the quaternary ammonium surface active agent is selected from the group consisting of benzalkonium chloride, cetalkonium chloride, cetylpyridinium chloride, benzethonium chloride and cethexonium bromide.
13. The composition according to claim 6 wherein the complex-forming compound is present in an amount of about 0.01 - 1%.
14. The composition according to claim 9 wherein the active oxygen yielding compound is selected from the group consisting of urea peroxide, benzoyl peroxide, lauryl peroxide, peroxyacetic acid, sodium peroxydisulfate, di-tert-butyl peroxide, methyl ethyl ketone peroxide, sodium peroxide, and sodium perborate.
15. The composition of claim 10 wherein the quaternary ammonium surface active agent is selected from the group consisting of benzalkonium chloride, cetalkonium chloride, cetylpyridinium chloride, benzethonium chloride, and cethexonium bromide.
16. The composition of claim 10 wherein the concentration of hydrogen peroxide is from about 0.5% to about 10%, the concentration of the zwitterionic detergent is from about 5% to about 30%, and the concentration of the block copolymer is from about 5% to about 25%.
1. A stable liquid concentrate composition consisting essentially of:
2. The composition of claim 1 wherein the active oxygen yielding compound is hydrogen peroxide.
3. The composition of claim 2 wherein the concentration of hydrogen peroxide is from about 0.5% to about 10%.
4. The composition according to claim 1 wherein the active oxygen-containing compound is selected from the group consisting of urea peroxide, benzoyl peroxide and hydrogen peroxide.
5. The composition according to claim 1 including 0.01 - 10% of a water soluble quaternary ammonium surface active agent.
6. The composition according to claim 1 including a complex-forming compound selected from the group consisting of ethylene-diaminetetraacetic acid, diethylenetriaminepentaacetic acid, and their water-soluble salts.
7. The composition according to claim 1 including acetanilid.
8. The composition of claim 1 including 0.01 - 10% of a water soluble quaternary ammonium surface-active and a complex-forming compound selected from the group consisting of ethylene-diaminetetraacetic acid, diethylenetriaminepentaacetic acid, and their water-soluble salts.
9. The composition according to claim 1 wherein the concentration of the active oxygen yielding compound is from about 0.5% to about 10%.
10. A stable liquid concentrate consisting essentially of:
11. The composition of claim 2 wherein the zwitterionic detergent is dodecyl sulfobetaine.
12. The composition according to claim 5 wherein the quaternary ammonium surface active agent is selected from the group consisting of benzalkonium chloride, cetalkonium chloride, cetylpyridinium chloride, benzethonium chloride and cethexonium bromide.
13. The composition according to claim 6 wherein the complex-forming compound is present in an amount of about 0.01 - 1%.
14. The composition according to claim 9 wherein the active oxygen yielding compound is selected from the group consisting of urea peroxide, benzoyl peroxide, lauryl peroxide, peroxyacetic acid, sodium peroxydisulfate, di-tert-butyl peroxide, methyl ethyl ketone peroxide, sodium peroxide, and sodium perborate.
15. The composition of claim 10 wherein the quaternary ammonium surface active agent is selected from the group consisting of benzalkonium chloride, cetalkonium chloride, cetylpyridinium chloride, benzethonium chloride, and cethexonium bromide.
16. The composition of claim 10 wherein the concentration of hydrogen peroxide is from about 0.5% to about 10%, the concentration of the zwitterionic detergent is from about 5% to about 30%, and the concentration of the block copolymer is from about 5% to about 25%.
Description:
This invention relates to new liquid concentrate compositions which have a unique stabilizing action on oxygen yielding compounds, and more particularly relates to stable aqueous solutions of per-oxygen compounds in a surface active vehicle.
In the past, the stabilization of oxygen yielding compositions has presented many problems to the art. A variety of stabilizers have been used for the purpose of stabilizing simple aqueous solutions containing active oxygen yielding compounds. Among those tested and found effective are compounds such as acetophenetidin, acetanilid, ascorbic acid, silicate salts, stannate salts, and oxyquinolines. Generally, an acid environment appears to add to the stability of hydrogen peroxide and related oxygen yielding compositions. Stabilized peroxide containing solutions have many well-known broad industrial as well as consumer uses. There are many additional needs, however, which could be more adequately filled if a diversity of stabilized oxygen yielding compositions were available in detergent vehicles.
Recently, the use of hexachlorophene containing preparations for contact with the human skin has been discouraged becasue these preparations have been shown to cause brain damage in animals through absorption and elicit untoward systemic effects. Hexachlorophene containing preprations have been used for a wide variety of purposes such as a skin bathing composition in infant nurseries and cleansing compositions in preoperative preparation and scrubbing. A continuing search is going on for a suitable replacement for such hexachlorophene compositions.
The present invention has found that an aqueous concentrate containing an active oxygen yielding compound can be given extended shelf-life with little loss of active oxygen through the use of a combination of certain surfactants in certain amounts.
Accordingly, the present invention provides a stable liquid concentrate comprising about 0.1 - 50% of an active oxygen yielding compound; about 0.5 - 50% of a sulfobetaine or betaine surfactant; about 1 - 50% of a nonionic polyoxyethylene-polyoxypropylene surfactant and 10 - 80% water.
The concentrate can be diluted or used full strength and exhibits a loss of active oxygen of as little as 6.7% after 675 days. The concentrates can also be used as substitutes for hexachlorophenes containing compositions.
The invention consists in the novel compositions, methods, products, and improvements shown and described. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory but are not restrictive of the invention.
The liquid detergent concentrate of this invention is an aqueous solution. The fact that water is a good solvent for the other ingredients of the present invention, together with its ready availability, makes it the desirable base material for this concentrate. The water used in the preparation of the concentrates of this invention is highly purified water and is preferably purified by distillation using pyrex glass equipment. Properly deionized water essentially free of dissolved organic substances can also be used in preparing the concentrates.
Preliminary stability studies indicate that the use of a high purity water is an important factor in obtaining concentrates having extended shelf-life. Significantly extended shelf-life is obtained for the concentrates of this invention when the highest purity water is used. The concentrates of the present invention are formulated to be diluted at the time of use as explained in greater detail hereafter. Dilution at the time of use of the concentrates can be achieved by ordinary tap water without significantly altering the stablity of the diluted product, but only the highest purity water can be used to prepare the initial concentrate to insure an extended shelf-life.
In accordance with this invention, an active oxygen yielding compound is provided in the concentrate. The active oxygen yielding compounds are detergent vehicle soluble per-oxygen compounds and are used in amounts ranging from 0.1 - 50% by weight, preferably 0.5 - 10%, based on the total weight of the concentrate. The per compounds are bleaching agents that impart a high level of cleaning and bleaching power to the compositions of the present invention. The per compounds derive their bleaching power from the release of active oxygen. Preferably the active oxygen yielding compound is hydrogen peroxide and is used in amounts of 0.5 - 10%. The hydrogen peroxide may also be present wholly or partially in the form of addition products with such well known materials as urea, alkali borates, polyphosphates and orthophosphates. Metal peroxides, peroxyacids, alkyl peroxides, acyl peroxides, peroxyesters and perborates such as alkali metal perborates can also be used. Exemplary of suitable active oxygen yielding compounds for use in this invention are lauryl peroxide urea peroxide, benzoyl peroxide, lauroyl peroxide, peroxyacetic acid, sodium peroxydisulfate, di-tert-butyl peroxide, methyl ethyl ketone peroxide, sodium peroxide, and sodium perborate. A particular advantage in the use of hydrogen peroxide as a disinfectant, cleaing or a bleaching agent in the concentrates of the present invention is that it decomposes to yield active oxygen and water. Both of these resulting agents can be readily removed and are essentially non-additive to the material or tissue being treated.
In accordance with the invention, the concentrate contains a polyoxypropylene-polyoxyethylene block copolymer. This copolymer is a primary cleaning ingredient of the composition.
The products sold under the trademark "Pluronic" by Wyandotte Chemical Corp. are a series of closely related block polymers that may be generically classified as polyoxypropylene-polyoxyethylene condensates terminating in primary hydroxyl groups. They are formed by the condensation of propylene oxide onto a propylene glycol nucleus followed by the condensation of ethylene oxide onto both ends of the polyoxypropylene base. The polyoxyethylene hydrophilic groups on the ends of the molecule are controlled in length to constitute anywhere from 10% to 80% by weight of the final molecule. This series of products may be represented empirically by the formula: ##SPC1##
where a and c are statistically equal. These polyol block copolymers are nonionic surface agents.
The particular block copolymers used in the concentrates of the present invention are selected on the basis of their solubility, wetting effect, detergency, emulsification capability, foam properties and viscosity. Block copolymers having a solubility of at least one gram per 100 ml. of water and a molecular weight ranging between 1000 and 15,500 are useful in the present invention. Among the polyoxypropylene-polyoxyethylene block copolymers satisfying the above conditions are the following Pluronic copolymers: Pluronic F-127; Pluronic F-68; Pluronic F-108; and Pluronic L-62. The following Table I lists the properties of a number of the block copolymers that can be used in the present invention.
TABLE I ____________________________________________________________ ______________ Average Cloud Point Solubility FOAMING PROPERTIES PLURONIC Molecular In 1% Aq. In Foam Heights (mm)* Weight Solution, °C. Water at flow of 400ml/min. ____________________________________________________________ ______________ 1) L-62 2,500 32 >10 35 2) F-68 8,350 >100 >10 >600 3) F-108 15,500 >100 >10 425 4) F-127 11,500 >100 >10 250 ____________________________________________________________ ______________ * The Foam Height is the value obtained on a Dynamic Foam Tester Operated at a temperature of 120°F using a 0.1% polyol concentration at a flow rate of 400 ml./min. for ten minutes.
To perform the cleaning functions of the compositions of this invention, the block copolymers should be present in an amount of from 1 to 50 weight percent of the concentrate, and preferably are present in an amount of 5 to 25 percent of the concentrate.
In accordance with the invention, the concentrate contains a betaine or sulfobetaine surfactant. These surfactants are zwitterionic synthetic detergents and can be broadly described as derivatives of aliphatic quaternary ammonium compounds in which the aliphatic radicals can be straight chain or branched, and wherein one of the aliphatic substituents contains from about 8 to 24 carbon atoms and one contains an anionic water solubilizing group such as a carboxy or sulfonate group. When the anionic water solubilizing group is a sulfonate, the compounds are called sulfobetaine or sultaines and are commercially available from Textilana Corp., Hawthorne, Calif. When the anionic water solubilizing group is a carboxy group, the compounds are called betaines and are available from E. I. du Pont de Nemours, Inc.; Onyx Chemical Co., Jersey City, N. J.; and Textilana Corp. In the range from about pH 4 to pH 8, long chain betaines and sulfobetaines are equally ionized as acids and as bases and exist as zwitter ions or inner salts.
The betaine and sulfobetaine surfactants useful in the concentrates of this invention can be represented by the following formula: ##SPC2##
wherein R 2 is a long chain radical and contains an alkyl, alkenyl, or hydroxy alkyl radical of from about 8 to about 24 carbon atoms, from 0 to about 10 ethylene oxide moieties and from 0 to 1 glyceryl moiety; Y is nitrogen; R 1 and R 3 are short chain alkyl or monohydroxy alkyl groups containing 1 to about 3 carbon atoms, such as methyl, ethyl or hydroxy ethyl groups; x is 0 or 1; R 4 is an alkylene or hydroxy alkylene of from 1 to about 4 carbon atoms; and Z is a radical selected from the group consisting of carboxylate and sulfonate groups. Exemplary of suitable betaine and sulfobetaine compounds for use in the present invention are the following compounds:
cetyl sulfobetaine;
dodecyl sulfobetaine;
4-[N,N-di(2-hydroxyethyl)-N-octadecylammonio]-butane - 1 -carboxylate;
3-(N,N-dimethyl - N - hexadecylammonio) propane -1-sulfonate
3-(N,N-dimethyl - N - hexadecylammonia) - 2 -hydroxypropane - 1 - sulfonate
4-[N,N-di(2-hydroxyethyl)-N-(2-hydroxydodecyl) ammonio]-butane - 1 - carboxylate
Still other sulfobetaine surfactants which can be used in the present invention are described in U.S. Pat. Nos. 3,280,179; 3,539,521; 3,594,411 and 3,630,922, which are hereby incorporated by reference.
The betaine or sulfobetaine detergents described above are utilized in this invention in amounts of from 0.5% to about 50% by weight of the concentrate. Preferably, these detergents are utilized in amounts of from about 5 to about 30% by weight of the concentrate.
The combination of a betaine or sulfobetaine surface active agent with a polyoxypropylene-polyoxyethylene block copolymer provides an aqueous concentrate that has an extended shelf life with respect to the active oxygen content of the concentrate. Thus, tests on concentrates prepared in accordance with this invention show no loss of active oxygen after four weeks, and only 6.7% loss after 675 days.
In addition to the above ingredients, various optional additives customarily used for a particular application may be incorporated in the concentrates of the present invention.
For example, the stabilizing effects of acetanilid on peroxy compounds is known to those skilled in the art. Acetanilid can be used in the concentrates of the present invention to provide added stability during use of diluted compositions prepared from the concentrate, especially when the concentrates are diluted with water that has not been properly purified. The acetanilid can be incorporated in the concentrate in amounts of 0 - 0.5%.
The concentrate of this invention can optionally contain about 0.01 - 1% of complex-forming compounds such as ethylene-diaminetetraacetic acid or its water soluble salts, or analogues, such as diethylene-triaminepentaacetic acid or its water soluble salts. The alkali metal salts of the acids are presently preferred, such as, monosodium edetate (ethylenediaminetetraacetate), disodium edetate and sodium diethylene triamine pentaacetate. Combinations of several complex-forming compounds can be used as well.
The complex-forming compounds impart additional cleaning power to the concentrates of this invention, and this is particularly so where insoluble chelatable metal ion salts of fatty acids, such as, for example, calcium stearate are to be removed from skin. The complex-forming compounds tie up divalent and trivalent cations often present in water, thereby preventing undesirable precipitates from forming.
The concentrates of this invention can optionally contain from 0.01 to 10% of a quaternary ammonium surface active agent. The quaternary ammonium surface active agents useful in this invention are exemplified by benzalkonium chloride, cetalkonium chloride, cetylpyridinium chloride, benzethonium chloride, and cethexonium bromide. These agents may be added for the purpose of increasing detergency and foam stability as well as for imparting residual germicidal activity. Active oxygen releasing compounds such as hydrogen peroxide react relatively quickly upon contact with oxidizable organic materials and their germicidal effectiveness is dissipated soon thereafter. The foam stabilizing effect of quaternary ammonium surface active agents in the concentrates of this invention contributes to the overall combination of desirable properties achieved by the concentrates of this invention.
The use of concentrates having at least three different types of surfactants enables the stability and physical properties of the concentrates to be varied as required by different end uses of the concentrates. For example, if more foaming is desired, the concentration of the betaine and/or sulfobetaine and/or quaternary ammonium surfactant can be increased. If less foam and less detergency is desired, the concentration of the polyoxypropylene-polyoxyethylene copolymer can be increased and/or the amount of the quaternary ammonium surfactant and/or the betaine or sulfobetaine surfactant can be decreased.
The liquid detergent concentrates of this invention have a wide pH range between 2 and 10 and preferably have a pH between 3 and 7. A desired acid pH can be imparted to the concentrates of this invention by addition of hydrochloric acid, phosphoric acid, acetic acid, sulfuric acid, nitric acid or any other acid which does not react with active oxygen. Similarly, adjustment of the pH in the alkaline region can be accomplished with any non-reactive water-soluble non-volatile basic substance such as for example, sodium hydroxide, potassium hydroxide, borax, trisodium phosphate, and the like.
The concentrates of this invention are useable for many different purposes in industry and/or in the household. The concentrates have broad medical and non-medical applications as nonselective germicides and bleaching agents. Examples include the bleaching of hair, textiles, wood and/or plastic composition, use in the bleaching steps of paper manufacture; the cleaning, degerming and/or bleaching of floors, work surfaces, animal areas, laboratories, sterile work areas and the like; the cleaning and degerming of skin areas prior to surgery; use as a presurgical hand scrubbing agent; and the cleaning and degerming of infants in nurseries to prevent cross infection. Other uses include the cleansing of skin areas afflicted with injury, cuts, bruises, rashes, pimples, acne, eczema, etc.; the bleaching, cleaning and degerming and deodorizing of body cavities such as the ears, vagina and the rectum.
In use, the concentrates can be diluted for a particular application or used full strength. Water of a high degree of purity is preferably used to bring about dilution and prolong the stability of the resulting compostion, but ordinary tap water can be used if pure water is not available. Dilutions of from 2 to 200 fold can be made with the concentrates of this invention.
The following examples are given by way of illustration to further explain the principles of the invention. These examples are merely illustrative and are not to be understood as limiting the scope and underlying principles of the invention in any way. All percentages referred to herein are by weight unless otherwise specifically indicated.
EXAMPLE 1
A liquid concentrate is prepared in accordance with the present invention having the following composition: Acetanilid 0.05% Disodium edetate 0.25% Benzalkonium chloride 0.05% Sulfobetaine DLH (Textilana Corp) 20.0 % Polyoxyethylene-Polyoxypropylene condensate (Pluronic F-127 Wyandotte Corp) 20.0 % Hydrogen Peroxide 2.0 % Hydrochloric acid (approximately) 0.1 % Adjust to pH 4.0 Purified Water, Q.S. ad 100.0 %
This concentrate is tested as a cleanser by acne patients and is subjectively found to be effective in promoting healing of acne lesions. In the test, the hands and face of the patient are wetted with water, followed by application with the finger tips of the concentrate to the lesions on the face and other affected parts. The cleanser is allowed to remain on the patient's skin for 1 to 2 minutes, and is then rinsed off with hot water. This treatment is performed for 10 to 21 days.
Several applications of the concentrate of this example along the hair line causes the hair to be bleached. The concentrate can thus be used as a cosmetic hair bleach, but it must be kept out of the eyes.
The germicidal and bactericidal activity of the concentrate is tested against the following organisms:
1. Staphylococcus aureus
2. Streptococcus pyogenes
3. Escherichia coli
4. Candida albicans
5. Pseudomonas aeruginosa
A concentrate identical to the above concentrate but lacking benzalkonium chloride is also tested against the organisms.
Twenty-four hour broth cultures of the above microorganisms are centrifuged and resuspended in normal saline. Each bacterial suspension in the amount of 0.2 ml is added to 3.8 ml samples of each concentrate and to 3.8 ml samples of a control solution of normal saline. The resulting suspensions are then held at room temperature and tested for bacterial viability at 15 minutes, 30 minutes and 1 hour post-inoculation. Tests for bacterial viability are performed by inoculating 0.1 ml of sample into 0.9 ml Tryptic Soy Broth and incubating at 37° C for 1 week.
All organisms are killed within 15 minutes exposure. Control cultures are all in the range of 10 6 to 10 8 colony forming units (CFU) per ml.
The stability of the concentrate of this example is evaluated in 2 oz. natural polyethylene containers at room temperature (68°-72° F) using a standard potassium permanganate titration procedure for the assay. The data obtained are presented in Table II.
TABLE II ______________________________________ Days Stored % H 2 O 2 Lost ______________________________________ 0 -- 2 0 19 0 28 0 36 1.1% 143 5.0% 323 6.7% 480 5.5% 675 6.7% ______________________________________
These data establish that the concentrates have more than adequate shelf-like for commercial application and do not require any significant overages of the active oxygen yielding substances.
EXAMPLE II
A liquid concentrate in accordance with the present invention is prepared having the following composition:
cetyl betaine (du Pont) 25.0% polyoxypropylene-polyoxyethylene condensate (Pluronic F-68, Wyandotte) 15.0% hydrogen peroxide 30.0% phosphoric acid to pH 4.0 purified water Q.S. 100.0%
This concentrate can be diluted with water as required to form a dilute solution containing about 0.1% to 20.0% of concentrate. The diluted concentrate can be used to bleach, degerm and/or clean dirtied, aged, or discolored surfaces such as plastic floor coverings, wood, desk or laboratory bench surfaces and the like. The concentrate is particularly effective in removing aged or yellowed wax.
EXAMPLE III
Another concentrate is prepared having the following composition:
Urea peroxide 10.0% Polyoxypropylene-polyoxyethylene concentrate (Pluronic F-108) 10.0% Disodium edetate 0.1% Dodecyl sulfobetaine 10.0% Cetalkonium chloride 0.25% Purified Water Q.S., ad 100 %
This concentrate is useful as a skin cleanser and debriding agent. The urea has a desirable keratolylic effect particularly in those instances where a hyperkeratotic skin condition exists. The concentrate when diluted about 1:20 with water is an effective vaginal douche.
EXAMPLE IV
Another concentrate is prepared having the following composition:
Benzoyl peroxide 5.0% Polyoxypropylene-polyoxyethylene concentrate (Pluronic L-62) 15.0% Lauryl sulfobetaine DCH (Textilana) 5.0% Cetylpyridinium chloride 0.05% Acetanilid 0.01% Sodium diethylene triamine pentaacetate 0.2% Purified Water, Q.S. 100.0%
The concentrate of this example can be used for the same purposes and in the same manner as the concentrate of Example I but is less harsh in removing natural skin oils, e.g., in presurgical scrub.
EXAMPLE V
Another concentrate is prepared having the following composition:
Hydrogen peroxide 1.0% Polyoxyethylene-Polyoxypropylene condensate (Pluronic F-127) 20.0% Cetyl sulfobetaine DLH (Textilana) 15.0% Monosodium edetate 0.1% Benzalkonium chloride 0.1% Purified water, Q.S. 100.0%
This concentrate is particularly useful in infant nurseries as a skin bathing composition. Although the concentrate is also effective in preoperative preparation and scrubbing, it has the desired mildness as well as adequate antimicrobial effects. This concentrate is thus a valuable substitute for hexachlorophene containing detergent compositions that have been used for these purposes.
A product of gel consistency at room temperature is produced when the amount of Pluronic F-127 used in the concentrate of this example is increased to 23% to 27 %.
This invention in its broader aspects is not limited to the specific details shown and described, but departures may be made from such details shown and described, but departures may be made from such details within the scope of the accompanying claims without departing from the principles of the invention and without sacrificing its chief advantages.
In the past, the stabilization of oxygen yielding compositions has presented many problems to the art. A variety of stabilizers have been used for the purpose of stabilizing simple aqueous solutions containing active oxygen yielding compounds. Among those tested and found effective are compounds such as acetophenetidin, acetanilid, ascorbic acid, silicate salts, stannate salts, and oxyquinolines. Generally, an acid environment appears to add to the stability of hydrogen peroxide and related oxygen yielding compositions. Stabilized peroxide containing solutions have many well-known broad industrial as well as consumer uses. There are many additional needs, however, which could be more adequately filled if a diversity of stabilized oxygen yielding compositions were available in detergent vehicles.
Recently, the use of hexachlorophene containing preparations for contact with the human skin has been discouraged becasue these preparations have been shown to cause brain damage in animals through absorption and elicit untoward systemic effects. Hexachlorophene containing preprations have been used for a wide variety of purposes such as a skin bathing composition in infant nurseries and cleansing compositions in preoperative preparation and scrubbing. A continuing search is going on for a suitable replacement for such hexachlorophene compositions.
The present invention has found that an aqueous concentrate containing an active oxygen yielding compound can be given extended shelf-life with little loss of active oxygen through the use of a combination of certain surfactants in certain amounts.
Accordingly, the present invention provides a stable liquid concentrate comprising about 0.1 - 50% of an active oxygen yielding compound; about 0.5 - 50% of a sulfobetaine or betaine surfactant; about 1 - 50% of a nonionic polyoxyethylene-polyoxypropylene surfactant and 10 - 80% water.
The concentrate can be diluted or used full strength and exhibits a loss of active oxygen of as little as 6.7% after 675 days. The concentrates can also be used as substitutes for hexachlorophenes containing compositions.
The invention consists in the novel compositions, methods, products, and improvements shown and described. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory but are not restrictive of the invention.
The liquid detergent concentrate of this invention is an aqueous solution. The fact that water is a good solvent for the other ingredients of the present invention, together with its ready availability, makes it the desirable base material for this concentrate. The water used in the preparation of the concentrates of this invention is highly purified water and is preferably purified by distillation using pyrex glass equipment. Properly deionized water essentially free of dissolved organic substances can also be used in preparing the concentrates.
Preliminary stability studies indicate that the use of a high purity water is an important factor in obtaining concentrates having extended shelf-life. Significantly extended shelf-life is obtained for the concentrates of this invention when the highest purity water is used. The concentrates of the present invention are formulated to be diluted at the time of use as explained in greater detail hereafter. Dilution at the time of use of the concentrates can be achieved by ordinary tap water without significantly altering the stablity of the diluted product, but only the highest purity water can be used to prepare the initial concentrate to insure an extended shelf-life.
In accordance with this invention, an active oxygen yielding compound is provided in the concentrate. The active oxygen yielding compounds are detergent vehicle soluble per-oxygen compounds and are used in amounts ranging from 0.1 - 50% by weight, preferably 0.5 - 10%, based on the total weight of the concentrate. The per compounds are bleaching agents that impart a high level of cleaning and bleaching power to the compositions of the present invention. The per compounds derive their bleaching power from the release of active oxygen. Preferably the active oxygen yielding compound is hydrogen peroxide and is used in amounts of 0.5 - 10%. The hydrogen peroxide may also be present wholly or partially in the form of addition products with such well known materials as urea, alkali borates, polyphosphates and orthophosphates. Metal peroxides, peroxyacids, alkyl peroxides, acyl peroxides, peroxyesters and perborates such as alkali metal perborates can also be used. Exemplary of suitable active oxygen yielding compounds for use in this invention are lauryl peroxide urea peroxide, benzoyl peroxide, lauroyl peroxide, peroxyacetic acid, sodium peroxydisulfate, di-tert-butyl peroxide, methyl ethyl ketone peroxide, sodium peroxide, and sodium perborate. A particular advantage in the use of hydrogen peroxide as a disinfectant, cleaing or a bleaching agent in the concentrates of the present invention is that it decomposes to yield active oxygen and water. Both of these resulting agents can be readily removed and are essentially non-additive to the material or tissue being treated.
In accordance with the invention, the concentrate contains a polyoxypropylene-polyoxyethylene block copolymer. This copolymer is a primary cleaning ingredient of the composition.
The products sold under the trademark "Pluronic" by Wyandotte Chemical Corp. are a series of closely related block polymers that may be generically classified as polyoxypropylene-polyoxyethylene condensates terminating in primary hydroxyl groups. They are formed by the condensation of propylene oxide onto a propylene glycol nucleus followed by the condensation of ethylene oxide onto both ends of the polyoxypropylene base. The polyoxyethylene hydrophilic groups on the ends of the molecule are controlled in length to constitute anywhere from 10% to 80% by weight of the final molecule. This series of products may be represented empirically by the formula: ##SPC1##
where a and c are statistically equal. These polyol block copolymers are nonionic surface agents.
The particular block copolymers used in the concentrates of the present invention are selected on the basis of their solubility, wetting effect, detergency, emulsification capability, foam properties and viscosity. Block copolymers having a solubility of at least one gram per 100 ml. of water and a molecular weight ranging between 1000 and 15,500 are useful in the present invention. Among the polyoxypropylene-polyoxyethylene block copolymers satisfying the above conditions are the following Pluronic copolymers: Pluronic F-127; Pluronic F-68; Pluronic F-108; and Pluronic L-62. The following Table I lists the properties of a number of the block copolymers that can be used in the present invention.
TABLE I ____________________________________________________________ ______________ Average Cloud Point Solubility FOAMING PROPERTIES PLURONIC Molecular In 1% Aq. In Foam Heights (mm)* Weight Solution, °C. Water at flow of 400ml/min. ____________________________________________________________ ______________ 1) L-62 2,500 32 >10 35 2) F-68 8,350 >100 >10 >600 3) F-108 15,500 >100 >10 425 4) F-127 11,500 >100 >10 250 ____________________________________________________________ ______________ * The Foam Height is the value obtained on a Dynamic Foam Tester Operated at a temperature of 120°F using a 0.1% polyol concentration at a flow rate of 400 ml./min. for ten minutes.
To perform the cleaning functions of the compositions of this invention, the block copolymers should be present in an amount of from 1 to 50 weight percent of the concentrate, and preferably are present in an amount of 5 to 25 percent of the concentrate.
In accordance with the invention, the concentrate contains a betaine or sulfobetaine surfactant. These surfactants are zwitterionic synthetic detergents and can be broadly described as derivatives of aliphatic quaternary ammonium compounds in which the aliphatic radicals can be straight chain or branched, and wherein one of the aliphatic substituents contains from about 8 to 24 carbon atoms and one contains an anionic water solubilizing group such as a carboxy or sulfonate group. When the anionic water solubilizing group is a sulfonate, the compounds are called sulfobetaine or sultaines and are commercially available from Textilana Corp., Hawthorne, Calif. When the anionic water solubilizing group is a carboxy group, the compounds are called betaines and are available from E. I. du Pont de Nemours, Inc.; Onyx Chemical Co., Jersey City, N. J.; and Textilana Corp. In the range from about pH 4 to pH 8, long chain betaines and sulfobetaines are equally ionized as acids and as bases and exist as zwitter ions or inner salts.
The betaine and sulfobetaine surfactants useful in the concentrates of this invention can be represented by the following formula: ##SPC2##
wherein R 2 is a long chain radical and contains an alkyl, alkenyl, or hydroxy alkyl radical of from about 8 to about 24 carbon atoms, from 0 to about 10 ethylene oxide moieties and from 0 to 1 glyceryl moiety; Y is nitrogen; R 1 and R 3 are short chain alkyl or monohydroxy alkyl groups containing 1 to about 3 carbon atoms, such as methyl, ethyl or hydroxy ethyl groups; x is 0 or 1; R 4 is an alkylene or hydroxy alkylene of from 1 to about 4 carbon atoms; and Z is a radical selected from the group consisting of carboxylate and sulfonate groups. Exemplary of suitable betaine and sulfobetaine compounds for use in the present invention are the following compounds:
cetyl sulfobetaine;
dodecyl sulfobetaine;
4-[N,N-di(2-hydroxyethyl)-N-octadecylammonio]-butane - 1 -carboxylate;
3-(N,N-dimethyl - N - hexadecylammonio) propane -1-sulfonate
3-(N,N-dimethyl - N - hexadecylammonia) - 2 -hydroxypropane - 1 - sulfonate
4-[N,N-di(2-hydroxyethyl)-N-(2-hydroxydodecyl) ammonio]-butane - 1 - carboxylate
Still other sulfobetaine surfactants which can be used in the present invention are described in U.S. Pat. Nos. 3,280,179; 3,539,521; 3,594,411 and 3,630,922, which are hereby incorporated by reference.
The betaine or sulfobetaine detergents described above are utilized in this invention in amounts of from 0.5% to about 50% by weight of the concentrate. Preferably, these detergents are utilized in amounts of from about 5 to about 30% by weight of the concentrate.
The combination of a betaine or sulfobetaine surface active agent with a polyoxypropylene-polyoxyethylene block copolymer provides an aqueous concentrate that has an extended shelf life with respect to the active oxygen content of the concentrate. Thus, tests on concentrates prepared in accordance with this invention show no loss of active oxygen after four weeks, and only 6.7% loss after 675 days.
In addition to the above ingredients, various optional additives customarily used for a particular application may be incorporated in the concentrates of the present invention.
For example, the stabilizing effects of acetanilid on peroxy compounds is known to those skilled in the art. Acetanilid can be used in the concentrates of the present invention to provide added stability during use of diluted compositions prepared from the concentrate, especially when the concentrates are diluted with water that has not been properly purified. The acetanilid can be incorporated in the concentrate in amounts of 0 - 0.5%.
The concentrate of this invention can optionally contain about 0.01 - 1% of complex-forming compounds such as ethylene-diaminetetraacetic acid or its water soluble salts, or analogues, such as diethylene-triaminepentaacetic acid or its water soluble salts. The alkali metal salts of the acids are presently preferred, such as, monosodium edetate (ethylenediaminetetraacetate), disodium edetate and sodium diethylene triamine pentaacetate. Combinations of several complex-forming compounds can be used as well.
The complex-forming compounds impart additional cleaning power to the concentrates of this invention, and this is particularly so where insoluble chelatable metal ion salts of fatty acids, such as, for example, calcium stearate are to be removed from skin. The complex-forming compounds tie up divalent and trivalent cations often present in water, thereby preventing undesirable precipitates from forming.
The concentrates of this invention can optionally contain from 0.01 to 10% of a quaternary ammonium surface active agent. The quaternary ammonium surface active agents useful in this invention are exemplified by benzalkonium chloride, cetalkonium chloride, cetylpyridinium chloride, benzethonium chloride, and cethexonium bromide. These agents may be added for the purpose of increasing detergency and foam stability as well as for imparting residual germicidal activity. Active oxygen releasing compounds such as hydrogen peroxide react relatively quickly upon contact with oxidizable organic materials and their germicidal effectiveness is dissipated soon thereafter. The foam stabilizing effect of quaternary ammonium surface active agents in the concentrates of this invention contributes to the overall combination of desirable properties achieved by the concentrates of this invention.
The use of concentrates having at least three different types of surfactants enables the stability and physical properties of the concentrates to be varied as required by different end uses of the concentrates. For example, if more foaming is desired, the concentration of the betaine and/or sulfobetaine and/or quaternary ammonium surfactant can be increased. If less foam and less detergency is desired, the concentration of the polyoxypropylene-polyoxyethylene copolymer can be increased and/or the amount of the quaternary ammonium surfactant and/or the betaine or sulfobetaine surfactant can be decreased.
The liquid detergent concentrates of this invention have a wide pH range between 2 and 10 and preferably have a pH between 3 and 7. A desired acid pH can be imparted to the concentrates of this invention by addition of hydrochloric acid, phosphoric acid, acetic acid, sulfuric acid, nitric acid or any other acid which does not react with active oxygen. Similarly, adjustment of the pH in the alkaline region can be accomplished with any non-reactive water-soluble non-volatile basic substance such as for example, sodium hydroxide, potassium hydroxide, borax, trisodium phosphate, and the like.
The concentrates of this invention are useable for many different purposes in industry and/or in the household. The concentrates have broad medical and non-medical applications as nonselective germicides and bleaching agents. Examples include the bleaching of hair, textiles, wood and/or plastic composition, use in the bleaching steps of paper manufacture; the cleaning, degerming and/or bleaching of floors, work surfaces, animal areas, laboratories, sterile work areas and the like; the cleaning and degerming of skin areas prior to surgery; use as a presurgical hand scrubbing agent; and the cleaning and degerming of infants in nurseries to prevent cross infection. Other uses include the cleansing of skin areas afflicted with injury, cuts, bruises, rashes, pimples, acne, eczema, etc.; the bleaching, cleaning and degerming and deodorizing of body cavities such as the ears, vagina and the rectum.
In use, the concentrates can be diluted for a particular application or used full strength. Water of a high degree of purity is preferably used to bring about dilution and prolong the stability of the resulting compostion, but ordinary tap water can be used if pure water is not available. Dilutions of from 2 to 200 fold can be made with the concentrates of this invention.
The following examples are given by way of illustration to further explain the principles of the invention. These examples are merely illustrative and are not to be understood as limiting the scope and underlying principles of the invention in any way. All percentages referred to herein are by weight unless otherwise specifically indicated.
EXAMPLE 1
A liquid concentrate is prepared in accordance with the present invention having the following composition: Acetanilid 0.05% Disodium edetate 0.25% Benzalkonium chloride 0.05% Sulfobetaine DLH (Textilana Corp) 20.0 % Polyoxyethylene-Polyoxypropylene condensate (Pluronic F-127 Wyandotte Corp) 20.0 % Hydrogen Peroxide 2.0 % Hydrochloric acid (approximately) 0.1 % Adjust to pH 4.0 Purified Water, Q.S. ad 100.0 %
This concentrate is tested as a cleanser by acne patients and is subjectively found to be effective in promoting healing of acne lesions. In the test, the hands and face of the patient are wetted with water, followed by application with the finger tips of the concentrate to the lesions on the face and other affected parts. The cleanser is allowed to remain on the patient's skin for 1 to 2 minutes, and is then rinsed off with hot water. This treatment is performed for 10 to 21 days.
Several applications of the concentrate of this example along the hair line causes the hair to be bleached. The concentrate can thus be used as a cosmetic hair bleach, but it must be kept out of the eyes.
The germicidal and bactericidal activity of the concentrate is tested against the following organisms:
1. Staphylococcus aureus
2. Streptococcus pyogenes
3. Escherichia coli
4. Candida albicans
5. Pseudomonas aeruginosa
A concentrate identical to the above concentrate but lacking benzalkonium chloride is also tested against the organisms.
Twenty-four hour broth cultures of the above microorganisms are centrifuged and resuspended in normal saline. Each bacterial suspension in the amount of 0.2 ml is added to 3.8 ml samples of each concentrate and to 3.8 ml samples of a control solution of normal saline. The resulting suspensions are then held at room temperature and tested for bacterial viability at 15 minutes, 30 minutes and 1 hour post-inoculation. Tests for bacterial viability are performed by inoculating 0.1 ml of sample into 0.9 ml Tryptic Soy Broth and incubating at 37° C for 1 week.
All organisms are killed within 15 minutes exposure. Control cultures are all in the range of 10 6 to 10 8 colony forming units (CFU) per ml.
The stability of the concentrate of this example is evaluated in 2 oz. natural polyethylene containers at room temperature (68°-72° F) using a standard potassium permanganate titration procedure for the assay. The data obtained are presented in Table II.
TABLE II ______________________________________ Days Stored % H 2 O 2 Lost ______________________________________ 0 -- 2 0 19 0 28 0 36 1.1% 143 5.0% 323 6.7% 480 5.5% 675 6.7% ______________________________________
These data establish that the concentrates have more than adequate shelf-like for commercial application and do not require any significant overages of the active oxygen yielding substances.
EXAMPLE II
A liquid concentrate in accordance with the present invention is prepared having the following composition:
cetyl betaine (du Pont) 25.0% polyoxypropylene-polyoxyethylene condensate (Pluronic F-68, Wyandotte) 15.0% hydrogen peroxide 30.0% phosphoric acid to pH 4.0 purified water Q.S. 100.0%
This concentrate can be diluted with water as required to form a dilute solution containing about 0.1% to 20.0% of concentrate. The diluted concentrate can be used to bleach, degerm and/or clean dirtied, aged, or discolored surfaces such as plastic floor coverings, wood, desk or laboratory bench surfaces and the like. The concentrate is particularly effective in removing aged or yellowed wax.
EXAMPLE III
Another concentrate is prepared having the following composition:
Urea peroxide 10.0% Polyoxypropylene-polyoxyethylene concentrate (Pluronic F-108) 10.0% Disodium edetate 0.1% Dodecyl sulfobetaine 10.0% Cetalkonium chloride 0.25% Purified Water Q.S., ad 100 %
This concentrate is useful as a skin cleanser and debriding agent. The urea has a desirable keratolylic effect particularly in those instances where a hyperkeratotic skin condition exists. The concentrate when diluted about 1:20 with water is an effective vaginal douche.
EXAMPLE IV
Another concentrate is prepared having the following composition:
Benzoyl peroxide 5.0% Polyoxypropylene-polyoxyethylene concentrate (Pluronic L-62) 15.0% Lauryl sulfobetaine DCH (Textilana) 5.0% Cetylpyridinium chloride 0.05% Acetanilid 0.01% Sodium diethylene triamine pentaacetate 0.2% Purified Water, Q.S. 100.0%
The concentrate of this example can be used for the same purposes and in the same manner as the concentrate of Example I but is less harsh in removing natural skin oils, e.g., in presurgical scrub.
EXAMPLE V
Another concentrate is prepared having the following composition:
Hydrogen peroxide 1.0% Polyoxyethylene-Polyoxypropylene condensate (Pluronic F-127) 20.0% Cetyl sulfobetaine DLH (Textilana) 15.0% Monosodium edetate 0.1% Benzalkonium chloride 0.1% Purified water, Q.S. 100.0%
This concentrate is particularly useful in infant nurseries as a skin bathing composition. Although the concentrate is also effective in preoperative preparation and scrubbing, it has the desired mildness as well as adequate antimicrobial effects. This concentrate is thus a valuable substitute for hexachlorophene containing detergent compositions that have been used for these purposes.
A product of gel consistency at room temperature is produced when the amount of Pluronic F-127 used in the concentrate of this example is increased to 23% to 27 %.
This invention in its broader aspects is not limited to the specific details shown and described, but departures may be made from such details shown and described, but departures may be made from such details within the scope of the accompanying claims without departing from the principles of the invention and without sacrificing its chief advantages.