LU86166A1 - AERIAL DISINFECTANT COMPOSITION - Google Patents

Description

. -ψ

The present invention relates to new compositions intended to be used for disinfecting surfaces by air.

Such compositions are known in principle and currently used in various aerosol generating devices such as those described by the Applicant in its French patents 1,568,295, 75.02188, 75.18474, 76.36270 and 77.12479.

Up to now, compositions of this kind have essentially contained formalin as active ingredient, the other constituents appearing in these compositions having only a subsidiary role, their proportion being insufficient for them to exert their own action, at least to an appreciable degree.

The recent developments in studies on the dangers presented by formalin in various medical fields have prompted the Applicant to seek a new composition in which formalin would no longer appear, but which would nevertheless exert a satisfactory, if not even better, disinfecting activity.

The Applicant's research therefore led her to the surprising finding that such a result could be achieved by means of the combination, in determined proportions of several components, known in themselves, but which did not individually possess the qualities required for this job.

The first component of the compositions according to the invention is chosen from the class of methyl-isopropylphenols, such as 5-methyl-2-isopropyl-phenol, or m-thymol, 2-methyl-5-isopropyl-phenol, or carvacrol (or iso-thymol), or their chlorinated derivatives. The preferred member of this group is m-thymol, and will be referred to hereinafter as "thymol".

The second component of the compositions according to the invention is chosen from the class of alkyl ethers of glycols, such as mono-butyl ether of ethylene glycol or ethyl ether of diethylene glycol. The preferred member of this group is the mono-butyl ether of ethylene glycol, well known under the trademark "Butyl Cellosolve" and will be referred to hereinafter under the simplified name "butyl glycol".

The third component of the compositions according to the invention is water.

If we now consider each of these three 40 components, we are led to the following observations: 2 Ύ

Thymol has been known for a very long time as a product of natural origin as a sanitizing agent, for its destructive action on molds and plant parasites, λ in this regard it has been proposed in pharmacies as an ointment and in alcoholic solution as contact disinfectant. Since it is not soluble in water, no preparation for airborne disinfection containing only thymol as an essential ingredient has been proposed to date.

Butylglycol is also known, but only as a solvent, without any bactericidal activity being reported. Its role in the compositions according to the invention is multiple: - Firstly, it has the effect of dissolving thymol; - Secondly, experience has shown that it possesses in itself a certain bactericidal activity, moreover quite weak; - Third, experience has surprisingly shown that this bactericidal activity is very markedly increased by the presence of thymol.

Finally, water is essential for the compositions according to the invention, to allow the aerosol forming apparatus to diffuse a solution, in the form of particles sufficiently fine to be deposited extremely slowly, in particular on the upper zones of the partitions, and to cross porous obstacles, such as blankets.

25 The presence of the appropriate proportion of water ensures the creation in the room to be disinfected of the relative humidity rate most favorable to the disinfecting action, of the order of at least 60-70¾ at 20eC.

The relative proportions of the three components in the compositions according to the invention are determined by the respective role of said components: - thymol becomes ineffective below 0-1¾ by weight, and makes the atmosphere difficult to breathe around 5¾. In practice, its optimal proportion is of the order of 0.75 to 35%.

- Butylglycol no longer assumes its solubilizing role below about 5%, and it exerts an unacceptable stripping action above 30¾. In practice, its optimal proportion is around 20¾.

40 - water normally represents the complement to 100¾.

3 t - finally, according to a variant coming within the framework of "the invention, part of the butylglycol can be replaced by 2-methyl-2,4-pentane-diol (or hexylene glycol), playing the role of the liver co-solvent and stabilizing adjuvant.

5 By way of nonlimiting example, a composition coming within the scope of the invention will contain, in% by weight:

Thymol 0.75

Butylglycol 20

Hexylene glycol 8 10 Water (demineralized) 71.25

Such a composition is obtained by cold dissolution of thymol in butylglycol, then, after addition of hexylene glycol, introduction of water with stirring. A slightly opalescent colorless liquid is obtained, with a density of 15 d20 „= 0.9867-0.9877, with a refractive index n2o · = 1.3660 - 1.3670, which can be stored for several years without loss of activity.

This composition is used as it is in an aerosol generating apparatus such as those mentioned above, at a dose of the order of 20 ml | nr of volume of air to be treated, for approximately 4 hours. An essential advantage of this composition is that it allows the room to be reoccupied after only 30 minutes of aeration, instead of the well-known difficulties which remain after use of the formalin-based compositions.

25 Bactericidal efficacy tests, carried out in accordance with French standard T-72-281 on the following strains of microorganisms:

BACTERIAL STRAINS

- Streptococcus faecalis CNCM 5855; 30 - Staphylococcus aureus - Oxford strain CNCM 53 | 54; - Pseudomonas aeruginosa CNCM A 22; - Escherichia coli CNCM 54127.

STRAINS OF MOLD

- Penicilium verrucosum Var - Cyclopium CNCM 1186-79.

35 YEAST STRAINS

- Candida albicans CNCM 1180-79.

led to the observation of a bactericidal activity equal to or greater than 5 on the bacterial strains and the yeast strains, and equal to or greater than 4 on the mold strains 40 (activity expressed in decimal Logs).

4 The relative humidity of the test room, which should be at least w 60-70’C at the end of the operation, was obtained by the diffusion of the product itself, thanks to its high water content.

Experience has shown that the diffusion of 17 g of the composition according to the invention increases the relative humidity of a room from 45 to 82%.

By way of illustration of the phenomenon of potentiation of the bactericidal activity of butylglycol by thymol, it may be indicated that, under identical experimental conditions (10.7 10 g | mJ - 4 h of contact) a 40 solution aqueous solution of butylglycol alone and the composition according to the invention respectively exert the following effects, expressed in decimal Logs:

Colibacilli Staphylococci Streptococci 15 Composition according to ——————————, the invention ^ 5.0 5.0 y 5.0

Butylglycol solution alone 1.21 0.33 0.42 - 20

These various results clearly demonstrate that the compositions according to the invention have an aerial disinfectant activity at least as satisfactory as that of the old formol-containing compositions, while eliminating their drawbacks, and that this activity must be attributed to a potentiation of effects, some of which have not yet been observed because of their weakness of the constituents of these compositions.

30

Claims (7)

1. Composition for the disinfection of surfaces by air, characterized in that it contains as active constituents on the one hand a methyl-isopropylphenol and on the other hand an alkyl ether of glycol, and in that said constituents are 5 solution in water. 2. Composition according to claim 1, characterized in that the methyl-isopropylphenol is m-thymol and the alkyl glycol ether is the monobutyl ether of 1 ethylene glycol or "butyl glycol". 3. Composition according to claims 1 and 2, characterized in that the proportion by weight of m-thymol is 0.1 to 5%, and preferably of the order of 0.5-0.75% and the proportion by weight of the butylglycol is 5 to 30% and preferably of the order of 20%, the rest of the composition consisting of water. 4. Composition according to claim 3, characterized in that a portion of the butylglycol is replaced by hexylene glycol. 5. Composition according to any one of claims 1 to 4, characterized in that it contains, in% by weight: 20 Thymol 0.75 Butylglycol 20 Hexylene glycol 8 Water (demineralized) 71.25 6. Application of the composition according to any one of claims 1 to 5 to the disinfection of surfaces, by diffusion of said composition in the form of an aerosol in the room to be treated. 7. Application according to claim 6, characterized in that the composition is diffused in the form of an aerosol at a rate of approximately 30 ml of air to be disinfected.