WO1995012976A1

WO1995012976A1 - Disinfectant composition

Info

Publication number: WO1995012976A1
Application number: PCT/GB1994/002490
Authority: WO
Inventors: Bruce Green
Original assignee: Bruce Green
Priority date: 1993-11-12
Filing date: 1994-11-11
Publication date: 1995-05-18
Also published as: GB9323270D0; AU8149294A

Abstract

A water soluble disinfectant composition comprising a blend of: (a) Alkyl Dimethyl Benzyl Ammonium Chloride; (b) Octyl Decyl Dimethyl Ammonium Chloride; and (c) Dodecylamine Sulphamate. The composition is particularly suitable for use in hard water areas, and maintains bactericidal activity in the presence of organic matter.

Description

DISINFECTANT COMPOSITION

Manufacturers have continually strived to produce a disinfectant detergent that combines ease of use, efficiency, user safety and financial economy for many years.

The objective has been elusive especially for compositions having active ingredient concentrations in an economically useful range that are effective against highly resistant bacteria, such as pseudomonas aeruginosa.

There is much prior art covering blends of quaternary ammonium compounds but these were not sold for use as broad spectrum hospital strength disinfectant cleaners, nor for use in hard water areas (water hardness of 300 to 400 ppm) .

Quaternary ammonium salts, in which either one or two of the substituents bonded to the quaternary nitrogen is a decyl radical comprising a mixture of primary 10-carbon atom branched chains, have been found to be very effective anti-microbial agents.

However, it is well known in the art that most biocidal quaternary ammonium compounds lose a considerable amount of their anti-microbial activity in the presence of hard water or organic soil, although certain heretofore known dialkyl dimethylammonium salts retain enough activity in the presence of these contaminants to be useful as bacteriostatic agents or sanitizers, but are inferior disinfectants. (A "sanitizer" is defined herein as a compound which reduces the concentration of microorganisms to a predetermined acceptable level without necessarily killing 100% of the organisms. A "disinfectant" is defined herein as a compound which kills 100% of the organisms) .

The effectiveness of quaternary ammonium compounds as sanitizers in hard water is usually measured by the "Ger icidal and Detergent Santizers Test". AOAC, 13th edition, page 61, (whereby increasing concentrations of hardness are used in order to determine the maximum water hardness ordinarily in terms of ppm. as calcium carbonate) in which a concentration of a predetermined amount of quaternary will kill 99.999% of the test organisms in the inoculum after 30 seconds of contact. This test is also often referred to as the "Hard Water Tolerance Test".

The "Germicidal and Detergent Sanitizers Test" may be adequate when the microbial contaminants involve only the less virulent, non-pathological species of microorganisms, or when the intent is merely to reduce the microbial content to predetermined acceptable levels. But when pathological species of microorganisms are the contaminants, then mere sanitization is insufficient. In such a case, only disinfection (100% kill of microorganisms) is tolerable.

The effectiveness of quaternaries as disinfectants is usually measured by the "Use Dilution Test" (AOAC, 13th edition, page 58) . This test measures the minimum concentration of a disinfectant which will kill 100% of the microorganisms on a hard surface in 10 minutes. Although the "Use Dilution Test" often serves as a means for comparing the effectiveness of quaternaries as disinfectants, it has a serious practical shortcoming; namely, it is performed in distilled water. Most communities in the World are in hard water areas and, since hard water reduces the anti-microbial effectiveness of disinfectant, it is necessary to modify the AOAC "Use Dilution Test" so that it will take water hardness into consideration.

In order to determine the actual effectiveness of quaternary disinfectants in hard water, certain aspects of the "Use Dilution Test" have here been combined with some aspects of the "Germicidal and Detergent Sanitizers Test". In such combined tests, a concentration of disinfectant is selected and, using that concentration, successive "Use Dilution Tests" are performed at increasing stepwise concentration of hard water contaminant until the quaternary fails to kill 100% of the test organisms. The maximum hard water level at which the quaternary passes this test is the significant measure of disinfectant effectiveness in hard water.

Since quaternary ammonium compounds are often used for cold sterilization, or chemical sterilization of hard surfaces, it is an object of this invention to provide disinfectants which are effective on hard surfaces, both in the presence of hard water as a diluent and in the presence of organic soil.

It is, in addition, an object of this invention to provide quaternary ammonium compounds which are superior disinfectants relative to the best of the known prior quaternaries, especially in the presence of hard water or organic soil.

Other objects will become apparent from the following description.

In accordance with the present invention, it has now been discovered that decyl-n-decyl dimethylammonium salts (wherein the term "decyl", as used throughout this specification, connotes a mixture of primary 10-carbon atom branched chains, as distinguished from the term "n- decyl", which connotes the normal decyl radical) are highly effective disinfectant agents in the presence of either hard water, organic soil, or both.

In addition to the discovery of the effectiveness of decyl-n-decyl dimethylammonium salts as disinfectants in hard water or organic soil, it has also been found that although both di-n-decyl and di-decyl dimethylammonium salts are relatively poor disinfectants, by themselves, in hard water or the presence of organic soil, when combined with dodecylamine sulphamate they exact a synergistic effect whereby the mixture also becomes an effective disinfectant both in hard water and in the presence of organic soil.

The "decyl" group of this invention is derived from commercial decyl alcohol. It has a CAS number of 68441- 08-6* and is essentially a mixture of branched primary alcohols in which the longest straight chain has at least two branches, the preponderant component preferably being tri ethylheptanol. The decyl-n-decyl dimethylammonium salts, as well as the di-decyl and di-n-decyl dimethylammonium salts, are prepared by synthesis.

The subject invention relates to a germicidal composition comprising alkyl dimethyl benzyl ammonium chloride, octydecyl dimethyl ammonium chloride and dodecylamine sulphamate and the use of such compositions as disinfectants. All percentages given herein are based on weight.

Based on the total active ingredients, the compositions may contain from 1-50% of the alkyl dimethyl benzyl ammonium chloride. The alkyl dimethyl benzyl ammonium chloride compositions used in the invention contain long chain alkyl groups having from 10 to 16 carbon atoms. Most preferable are those compositions which contain a blend of long chain alkyl groups, particularly C,₄, 50%; C₁₂, 40%; C₁₆, 10%.

The octyl decyl dimethyl ammonium chloride may be present at from 1-50%. The compositions may have a statistical distribution of approximately 25% dioctyl, 25% didecyl and 50% octyldecyl dimethyl ammonium chloride.

The dodecylamine sulphamate composition used contains average chain length distribution between C_g.ι₄. The most preferred composition contains > 90% C₁₂ or C,₄. The composition may contain 1 - 50% of dodecylamine sulphamate.

The invention therefore provides a concentrated disinfectant cleaner having both organic soil tolerance and hard water tolerance, comprising of a synergistic blend of quaternary compounds optionally together with nonionic surfactants, for example an alkoxylated fatty alcohol having 10 to 18 carbon atoms and 7 to 14 ethoxy or propoxy units, sequesterants, for example EDTA, corrosion inhibitors, for example Sodium Benzoate and solubilizers which together provide the following advantages:-

1. Greater germicidal efficiency, against Staph, choleraesuis and especially against Pseudomonas.

2. Maintains germicidal activity to a substantial degree in the presence of anionics.

3. Hard water tolerance is exceedingly high - well beyond anything observed in other commercial quaternary formulations.

4. Very high phenol coefficients. 5. Maintains bacterial activity in the presence of organic matter.

6. A superior bacteriostat.

7. Outstanding fungicide and fungistat.

8. Outstanding fabric mildew preventative (determined by the Fabric Mildew Fungistatic Test Method) .

9. Fast bactericidal action.

10. Highly surface active.

11. A sanitizer with no potable water rinse required.

12. Low toxicity comparable to other commercial disinfectants.

The composition was prepared and found to be effective against the following bacteria, fungi and viruses. Standard test methods were used, for example virucidal activity was determined by AFNOR Standard T 72-180 (March 1986) . Efficacy of 99.9% reduction in viability of bacteria and fungi. For viruses, a 4 decimal log reduction in the number of infectious units was found. Dilution ratios of from 1 in 10 to 1 in 150 were tried. Most effective were dilutions of from 1 in 10 to 1 in 100.

The following disinfectant formulation was prepared:

w/w Didecyl dimethyl ammonium chloride 15.0'

Alkyl (C₁₂-C,₄) dimethyl benzyl ammonium chloride 7.5'

Nonionic 5.0'

Dodecylamine Sulphamate 2.5' Ethanol 2.5'

Stabilizer, chelator, corrosion inhibitor 2.5'

Purified Water →IOO

Efficacy Data Summary

Disinfectant - prepared in 250ppm (CaC0₃) hard water, 5-

Organic Seru .

Organism Organism Pseudomonas aeruginosa Proteus vulgaris Staphylococcus aureus Salmonella schottmuelleri Staphyloccus aureus Salmonella typhi

(Methicillin resistant) Salmonella typhimurium Salmonella choleraesuis Serratia marcescens Brevibacterium ammoniagenes Shigella flexneri Enterobacter aerogenes Shigella dysenteriae Enterobacter cloacae Staohylococcus epidermidis Escherichia coli Streptococcus faeclis Escherichia coil Streptococcus faecalig -

(Methicillin resistant) (Methicillinresistant) Klebsiella pneumoniae Streptococcus pyogenes Klebsiella pneumoniae -

(Methicillin resistant)

Fungicide - prepared in 250ppm (CaC0₃) Hard water, 5% Organic Mildewstat Serum

Organism Organism

Trichophyton mentagrophytes Aspergilis niger

Candida albicans

Virucide - prepared in 250ppm (CaC0₃) Hard Water,

Organic Serum.

Virus Virus

HIV-1 (AIDS Virus) Influenza A/Brazil

Herpes Simplex Type 1 Rubella

Herpes Simplex Type 11 Vaccinia

Claims

1. A water soluble disinfectant composition comprising a blend of a) Alkyl Dimethyl Benzyl Ammonium Chloride, b) Octyl Decyl Dimethyl Ammonium Chloride, and c) Dodecylamine Sulphamate.

2. A composition comprising a blend of components as claimed in Claim 1 together with a surfactant.

3. A composition as claimed in Claim 2 wherein the surfactant is optimized to provide a no-rinse system.

4. A composition as claimed in Claim 2 or Claim 3 comprising a nonionic surfactant, preferably an alkoxylated fatty alcohol having 10 to 18 carbon atoms and 7 to 14 ethoxy or propoxy units.

5. A composition as claimed in any one of Claims 1 to 4 in the form of an aqueous solution.

6. A composition as claimed in any one of Claims 1 to 5 with a pH of between 3.00 - 12.00.

7. A composition as claimed in any one of Claims 1 to 6 further comprising a biguanide.

8. A composition as claimed in any one of Claims 1 to 7 further comprising a selected corrosion inhibitor, (e.g. Sodium Benzoate) .

9. A composition as claimed in any one of Claims 1 to 8 further comprising a selected chelating agent, e.g. (E.D.T.A.) .

10. The use of a composition as claimed in any one of Claims 1 to 9 in the preparation of a cleaning, disinfecting, sanitising or sterilising composition.

11. A process for killing bacteria by treatment with an aqueous solution of a composition as claimed in any one of Claims 1 to 9.