Synergistic disinfectant formulations with improved biocidal efficacy and stability

Abstract

Disinfectant synergistic formulations having improved biocidal efficacy and stability The invention relates to a biocidal formulation comprising: - from 0.2% to 30% by weight relative to the total weight of the formulation of at least one biocidal active substance, the active substance being or comprising a C1-C8 organic acid, in particular an alpha hydroxy carboxylic acid; - from 0.1% to 30% by weight relative to the total weight of the formulation, of at least one anionic surfactant, in particular chosen from carboxylates, sulfates or mixtures thereof; - from 0.09% to 15% by weight relative to the total weight of the formulation of non-ionic surfactants comprising: - a first non-ionic surfactant having a (C3-C7) alkyl chain, and - a second non-ionic surfactant having a (C8-C20) alkyl chain;in which the weight ratio expressed as a percentage of said first non-ionic surfactant to said biocidal active substance is between 5% and 200%, in particular between 15 and 100%.;

Description

Title of the invention: Disinfectant synergistic formulations having improved biocidal efficacy and stability

[0001] The present invention relates to environmentally friendly biocidal formulations containing an organic acid as an active ingredient, exhibiting improved biocidal efficacy and good stability over time.

[0002] The invention also relates to the use of these formulations for cleaning and disinfecting hard surfaces or for hand hygiene. Technical background

[0003] Most biocidal formulations intended for cleaning and disinfecting hands or hard surfaces with a broad spectrum of activity contain surfactants and antimicrobial active substances.

[0004] Surfactants are used in part, to help solubilize dirt on skin or hard surfaces, and / or to increase the wettability of surfaces or skin. Surfactants are generally selected from anionic, nonionic, amphoteric and / or cationic surfactants.

[0005] The commonly used antimicrobial active substances are generally derived from synthetic chemistry and are notably chosen from quaternary ammoniums, biguanides, triclosan, sodium hypochlorite, etc. These active substances, however, pose problems with regard to public health and the environment. Indeed, in addition to their toxicity to human health and the environment, studies show that they could be the cause of the growing resistance of microbial species, particularly with regard to antibiotics.

[0006] To overcome these drawbacks, more environmentally friendly biocidal formulations, including organic acids as active substance, have been developed in recent years.

[0007] Thus, patent EP 2 677 867 B1 proposes biocidal formulations of plant origin for cleaning and disinfecting surfaces, comprising an organic acid, in particular lactic acid and / or citric acid as biocidal active substance. More particularly, it describes a biodegradable formulation comprising lactic acid, a chelating agent: citric acid, an anionic surfactant of carboxylate or sulfate type and a non-ionic surfactant of C8-Ci0 or Cio-Cie alkyl glycoside type, having a biocidal efficacy comparable to that of conventional chemo-synthetic formulations.

[0008] However, biocidal formulations of plant origin may present compatibility problems and therefore limited stability over time or per- insufficient cleaning performance. Thus, document US 2010 / 101,605 discloses multifunctional “green” wipes, activated with water, using three functional compositions: —a cleaning formulation; —a disinfectant formulation; and —a perfume composition.

[0009] However, these functional compositions are implemented in a physically separate manner, in particular by impregnation of distinct areas of the wipe, so as to avoid problems of compatibility between the compositions and therefore of stability of the ingredients over time.

[0010] There is therefore a real need to provide biocidal formulations that can overcome the drawbacks of state-of-the-art biocidal formulations, in particular environmentally friendly biocidal formulations that are both effective and stable over time. Summary of the invention

[0011] An environmentally friendly biocidal formulation has now been developed, having good disinfecting and cleaning properties, combined with good stability over time.

[0012] This is accomplished by a combination of specific ingredients, in specific contents, said composition comprising at least one CrC8 organic acid as active substance, at least one anionic surfactant and at least one combination of non-ionic surfactants including a short-chain non-ionic surfactant, i.e. the lipophilic part of which comprises a C3-C7 alkyl chain, and a long-chain non-ionic surfactant, i.e. the lipophilic part of which comprises a C8-C2o alkyl chain.

[0013] More particularly, surprisingly, it has been shown that the use of a combination of a short-chain non-ionic surfactant and a long-chain non-ionic surfactant, in association with an anionic surfactant, makes it possible to improve the bactericidal and yeasticidal activity of a C1-C8 organic acid, while ensuring good stability of the formulation over time.

[0014] Thus, the invention relates firstly to a biocidal formulation comprising: - from 0.2% to 30% by weight relative to the total weight of the formulation of at least one biocidal active substance, the active substance being or comprising a CrC8 organic acid, in particular an alpha hydroxy carboxylic acid; - from 0.1% to 30% by weight relative to the total weight of the formulation, of at least one anionic surfactant, in particular chosen from carboxylates, sulfates or mixtures thereof; - from 0.09% to 15% by weight relative to the total weight of the formulation of non-ionic surfactants comprising: - a first non-ionic surfactant having a (C3-C7) alkyl chain, and - a second non-ionic surfactant having a (C8-C20) alkyl chain; in which: the weight ratio expressed as a percentage of said first non-ionic surfactant to said biocidal active substance is between 5% and 200%, in particular between 15 and 100%.

[0015] Other advantageous characteristics of the method according to the invention are specified below: -the organic acid in CrC8 is chosen from formic acid, lactic acid, citric acid, tartaric acid, glycolic acid, malic acid, maleic acid, fumaric acid, adipic acid, and succinic acid or a mixture thereof, in particular citric acid, lactic acid, tartaric acid, and malic acid or a mixture thereof; - the non-ionic surfactants are chosen from alkylpolyglycosides, ethoxylated or non-ethoxylated sorbitan esters, ethoxylated or non-ethoxylated polyglycerol esters, ethoxylated alcohols, ethoxylated oils, or mixtures thereof; -the first and / or the second non-ionic surfactant is / are an alkylpolyglycoside; -said first non-ionic surfactant is a (C3-C7) alkylpolyglycoside, in particular a (C5-C6) alkylpolyglycoside; -the first non-ionic surfactant is a D-xylopyranose (C3-C7) alkyl glycoside, in particular D-xylopyranose 3-methylbutyl glycoside; -the second non-ionic surfactant is a (C8-C2o) alkylpolyglycoside, in particular a (C8-Ci6) alkylpolyglycoside; - the weight ratio expressed as a percentage of the second non-ionic surfactant to said biocidal active substance is between 0.5 and 200%, in particular between 2 and 50%; -the first non-ionic surfactant represents from 15% to 90% by weight, in particular from 25% to 55% by weight of the total weight of the non-ionic surfactants present in the formulation; -the weight ratio expressed as a percentage of said first surfactant to said second non-ionic surfactant is between 15 and 500%, in particular from 55% to 200%; - the weight ratio expressed as a percentage of non-ionic surfactants to said active substance is between 5 and 200%, and more particularly between 15% and 100%; -the weight ratio expressed as a percentage of said anionic surfactant to said biocidal active substance is between 20% and 200%, in particular between 50% and 100%; -the anionic surfactant comprises at least one carboxylate-type surfactant, in particular 2-(2-octoxyethoxy)acetic acid or its sodium salt; -the anionic surfactant comprises an anionic surfactant of sulfate type, in particular having a C8-C20 alkyl or alkoxy chain, in particular sodium lauryl sulfate, or a sodium (C8-C16) alkyl ether sulfate; - the biocidal active substance of the formulation consists of a single organic acid, which is either lactic acid or citric acid, preferably lactic acid; -the formulation further comprises a pH adjusting agent, a thickening agent, a colorant, an emollient, a perfume or a mixture thereof; -the formulation is a so-called concentrated formulation and includes: - from 5% to 30% by weight relative to the total weight of the formulation of at least one biocidal active substance, the active substance being or comprising a C1-C8 organic acid, in particular an alpha hydroxy carboxylic acid; - from 5% to 30% by weight relative to the total weight of the formulation, in particular from 15% to 30% by weight, of at least one anionic surfactant, in particular chosen from carboxylates, sulfates or mixtures thereof; -from 1% to 12% by weight relative to the total weight of the formulation, in particular from 2% to 8% by weight of non-ionic surfactants, comprising: - a first non-ionic surfactant having a (C3-C7) alkyl chain, - a second non-ionic surfactant having a (C8-C20) alkyl chain; -the formulation is ready to use and includes: - from 0.2% to 2.5% by weight relative to the total weight of the formulation of at least one biocidal active substance, the active substance being an organic acid, CrC8, in particular an alpha hydroxy carboxylic acid; - from 0.1% to 5% by weight relative to the total weight of the formulation, in particular from 0.3% to 2% by weight, of at least one anionic surfactant, in particular chosen from carboxylates, sulfates or mixtures thereof; - from 0.09% to 4% by weight relative to the total weight of the formulation, in particular from 0.1% to 2% by weight of non-ionic surfactants, comprising: - a first non-ionic surfactant having a (C3-C7) alkyl chain, - a second non-ionic surfactant having a (C8-C20) alkyl chain; the first non-ionic surfactant represents from 0.009% to 1.8% by weight, in particular from 0.02% to 0.9% by weight relative to the total weight of the formulation; - according to this latter embodiment, the second non-ionic surfactant represents from 0.08% to 2% by weight relative to the total weight of the formulation; - the ready-to-use formulation is obtained by diluting a concentrated formulation with water, in particular in a ratio of 0.1 to 25% by weight (of the concentrated formulation in water), in particular 0.5 to 10% by weight, more specifically 0.5 to 5% by weight; -more than 50% by weight, preferably more than 75% by weight, in particular more than 95% by weight of the ingredients of the formulation are of renewable origin; -the formulation is biodegradable at more than 95%, notably at more than 98% according to OECD 301 guidelines.

[0016] According to another aspect, the invention also relates to the use of a biocidal formulation according to the invention for cleaning and disinfecting inanimate hard surfaces, including surfaces in contact with food; for human hygiene, in particular for disinfectant hand washing; cleaning and disinfecting the teats of animals before or after milking; cleaning and disinfecting fruits and vegetables. Brief description of the figures

[0017] [Fig. 1] represents a graph reporting the evaluation of the cleaning and degreasing power of the tested formulations. The y-axis corresponds to the scores attributed to the formulations.

[0018] [Fig.2] represents the photos of the bottles of the tested formulations allowing the stability of the formulations to be assessed. Detailed description

[0019] The invention is now described in more detail and in a non-limiting manner in the following description.

[0020] Unless otherwise indicated, all percentages relating to quantities are percentages by mass.

[0021] The mass percentages indicated for the ingredients of the biocidal formulation are expressed relative to the total weight of the formulation.

[0022] Weight ratios are expressed as a percentage.

[0023] For the purposes of the present application, the term “biocidal formulation” means a form mulation having at least one bactericidal activity, and preferably both bactericidal and yeasticidal activity.

[0024] By "bactericidal activity" is meant a formulation capable of meeting the requirements of EN 1276:2019 at 20°C against bacteria, in particular against one or more of Escherichia coli, Staphylococcus aureus, Enterococcus hirae, and Pseudomonas aeruginosa, more particularly against at least two, in particular at least three, more particularly against all four of these organisms, namely a microbial log reduction of at least 5 upon contact with the formulation, in a maximum of 5 minutes. In preferred embodiments, this requirement is met in 2 minutes, and in some embodiments, more specifically in one minute. In some specific embodiments, it has been found that for at least some organizations, the requirements of EN 1276 are already met in 30 seconds.

[0025] By "yeasticidal activity" is meant a formulation capable of meeting the requirements of EN 1650:2019 at 20°C, namely achieving a microbial log reduction of at least 4 under dirty conditions, in a maximum of 5 minutes. In preferred embodiments, this requirement is met within 1 minute, and in some embodiments, more specifically within 30 seconds.

[0026] By "cleaning power" is meant formulations capable of cleaning and solubilizing greasy soiling deposited on a hard surface. It was evaluated according to the method proposed by the "German Cosmetic, Toiletry, Perfumery and Detergent Association (IKW)" and published in SOFW Journal, Volume 144 (2018), with the indicated modifications.

[0027] By "renewably sourced ingredients" or "naturally sourced ingredients" is meant ingredients that include carbon from renewable sources.

[0028] Indeed, unlike ingredients derived from fossil materials, ingredients derived from renewable raw materials contain 14C. All carbon samples taken from living organisms (animals or plants) are in fact a mixture of 3 isotopes: 12C (representing approximately 98.892%), 13C (approximately 1.108%) and 14C (traces: 1.2.10-12%). The 14C / 12C ratio of living tissues is identical to that of the atmosphere. In the environment, 14C exists in two predominant forms: in mineral form, i.e., carbon dioxide (CO2), and in organic form, i.e., carbon integrated into organic molecules.

[0029] In a living organism, the 14C / 12C ratio is kept constant by metabolism because carbon is continually exchanged with the environment. Since the proportion of 14C is constant in the atmosphere, it is the same in the organism, as long as it is alive, since it absorbs this 14C as it absorbs 12C. The average ratio of 14C / 12C is equal to 1.2x10 12.

[0030] 12C is stable, meaning that the number of 12C atoms in a given sample is constant over time. 14C is radioactive (each gram of carbon in a living being contains enough of the 14C isotope to produce 13.6 disintegrations per minute) and the number of such atoms in a sample decreases over time (t) according to the law: n = no exp(-at) in which: no is the number of 14C at the origin (at the death of the creature, animal or plant), n is the number of 14C atoms remaining after time t, a is the decay constant (or radioactive constant); it is related to the half-life.

[0031] The half-life (or period) is the duration at the end of which any number of radioactive nuclei or unstable particles of a given species is reduced by half by disintegration; the half-life T1 / 2 is related to the disintegration constant a by the formula aTl / 2= In 2. The half-life of 14C is 5730 years.

[0032] Considering the half-life (T 1 / 2) of 14C, it is considered that the 14C content is constant from the extraction of the plant raw materials until the manufacture of the formulation, and even until the end of its use.

[0033] The applicant considers that an ingredient is derived from renewable raw materials if it contains at least 20% by mass of C of renewable origin on the total mass of carbon, preferably at least 50% by mass of C of renewable origin on the total mass of carbon.

[0034] In other words, an ingredient is derived from renewable raw materials if it contains at least 0.2.10 10% by mass of 14C, preferably 0.6.10 10% by mass of 14C.

[0035] Currently, there are at least two different techniques for measuring the 14C content of a sample: -By liquid scintillation spectrometry: This method consists of counting 'Beta' particles resulting from the disintegration of 14C: The Beta radiation from a sample of known mass (known number of 12C atoms) is measured over a certain time. This 'radioactivity' is proportional to the number of 14C atoms, which can thus be determined. The 14C present in the sample emits B- radiation, which, upon contact with the scintillating liquid (scintillator), gives rise to photons. These photons have different energies (between 0 and 156 Kev) and form what is called a 14C spectrum. According to two variants of this method, the analysis is carried out either on the CO2 previously produced by the carbon sample in a suitable absorbing solution, or on the benzene after prior conversion of the carbon sample into benzene. -By mass spectrometry: The sample is reduced to graphite or CO2 gas, analyzed in a mass spectrometer. This technique uses an accelerator and a mass spectrometer to separate the 14C ions from the 12C and thus determine the ratio of the two isotopes.

[0036] All these methods for measuring the 14C content of materials are described precisely in the ASTM D 6866 standards (in particular D6866-06) and in the ASTMD 7026 standards (in particular 7026-04). These methods measure the 14C / 12C ratio of a sample and compare it with the 14C / 12C ratio of a reference sample of 100% renewable origin, to give a relative percentage of C of renewable origin in the sample.

[0037] The measurement method preferably used in the case of the ingredients of the formulation of the invention is mass spectrometry described in the ASTM D6866-06 standard (“accelerator mass spectroscopy”).

[0038] For the purposes of this description, the term "biodegradable" means an organic substance capable of undergoing biodegradation according to a biological process of degradation into smaller and simpler molecules. Thus, degradation in the presence of oxygen leads to the production of CO2, water and minerals, while anaerobic biodegradation produces mainly methane. The biodegradability rate of the biocidal formulation represents the percentage by weight of biodegradable ingredients on the total weight of the formulation in dry mass, i.e. without water, and can be determined according to OECD guidelines 301.

[0039] “Stable biocidal formulations” means biocidal formulations capable of retaining their biocidal and cleaning effectiveness for a period of more than 2 years at room temperature. This stability can be evaluated according to the CIP AC MT46.3 method under accelerated aging conditions, in particular by increasing the temperature of the samples.

[0040] Biocidal formulation

[0041] Thus, according to a first aspect, the invention relates to a biocidal formulation comprising: - from 0.2% to 30% by weight of at least one biocidal active substance, the active substance being or comprising a CrC8 organic acid, in particular an alpha hydroxy carboxylic acid; - from 0.1% to 30% by weight of at least one anionic surfactant, in particular chosen from carboxylates, sulfates or mixtures thereof; - from 0.09% to 15% by weight of non-ionic surfactants comprising: - a first non-ionic surfactant having a (C3-C7) alkyl chain, and - a second non-ionic surfactant having a (C8-C20) alkyl chain; wherein the weight ratio of said first non-ionic surfactant to said biocidal active substance is between 5% and 200%, in particular between 15 and 100%.

[0042] The biocidal formulations according to the invention advantageously have bactericidal activity. Preferably, they are both bactericidal and yeasticidal. They also have cleaning and degreasing power.

[0043] In embodiments, more than 50% by weight, preferably more than 75% by weight, especially more than 95% by weight of the ingredients of the formulation are of renewable origin.

[0044] In embodiments, the formulation is more than 95% biodegradable, especially more than 98% according to OECD guidelines, especially OECD 301.

[0045] Active substance

[0046] The formulations according to the invention comprise at least one active substance, said active substance being or comprising a CrC8 organic acid.

[0047] For the purposes of this description, the range of values from "x to y wt%" applies to the total active substance content of the formulation, and therefore does not apply only to the organic acids present in the formulation.

[0048] In embodiments, the biocidal formulations according to the invention do not comprise biocidal active substances other than CrC8 organic acids. In other words, the biocidal active substance of the formulation is chosen from CrC8 organic acids and mixtures thereof, and does not comprise any other biocidal active substance, in particular chemico-synthetic.

[0049] In embodiments, the biocidal formulations according to the invention do not comprise alcohol, in particular ethanol.

[0050] The C1-C8 organic acid may in particular be chosen from formic acid, lactic acid, citric acid, tartaric acid, glycolic acid, malic acid, maleic acid, fumaric acid, adipic acid, and succinic acid or a mixture thereof.

[0051] These organic acids can advantageously be biodegradable and / or derived from renewable resources, particularly plant-based ones.

[0052] Preferably, the organic acid is an alpha hydroxy carboxylic acid, that is to say a carboxylic acid comprising at least one hydroxyl function, in the alpha position. Preferably, the organic acid is chosen from citric acid, lactic acid, tartaric acid, and malic acid or a mixture thereof.

[0053] In embodiments, the biocidal active ingredient of the formulation is a single organic acid which is either lactic acid or citric acid, preferably lactic acid.

[0054] Nonionic surfactants

[0055] In embodiments, the nonionic surfactants are selected from alkylpolyglycosides, ethoxylated or non-ethoxylated sorbitan esters, ethoxylated or non-ethoxylated polyglycerol esters, ethoxylated alcohols, ethoxylated vegetable oils, or mixtures thereof.

[0056] Depending on the length of the alkyl chain, surfactants fall into the first or second category of non-ionic surfactants. This is the length of the alkyl chain of the alkyl group in the alkylpolyglycoside; of the alkyl group of the acid part in sorbitan esters, ethoxylated or not; of the alkyl group of the acid part in polyglycerol esters, ethoxylated or not; of the alkyl group of the ethoxylated alcohol. Concerning ethoxylated oils, these belong- belong to the family of non-ionic surfactants having an alkyl chain (C8-C20).

[0057] These non-ionic surfactants can advantageously be biodegradable and / or derived from renewable resources, particularly plant-based.

[0058] In embodiments, the first and / or second non-ionic surfactant is / are an alkylpolyglycoside also called APG. An alkylpolyglycoside comprises a polymer chain comprising a sugar unit, comprising an alkoxy function. The sugar unit may be selected from glucose, dextrose, sucrose, fructose, galactose, maltose, maltotriose, lactose, cellobiose, mannose, ribose, dextran, talose, allose, xylose, levoglucan and D-xylopyranose. The alkyl chain of the alkoxy group may be linear or branched. It contains 3 to 7 carbon atoms in the first surfactant, i.e. propyl, butyl, pentyl, hexyl, heptyl chains, and between 8 and 20 carbon atoms in the second surfactant, i.e. octyl (caprylyl), nonyl, decyl (capryl), undecyl, dodecyl (lauryl), myristyl, palmityl, stearyl, arachidic chains.

[0059] In embodiments, said first non-ionic surfactant is a (C3-C7) alkylpolyglycoside, in particular a (C5-C6) alkylpolyglycoside.

[0060] In embodiments, the first non-ionic surfactant is a D-xylopyranose (C3-C7) alkyl glycoside, especially D-xylopyranose 3-methylbutyl glycoside.

[0061] In embodiments, the second non-ionic surfactant is a (C8-C20) alkylpolyglycoside, in particular a (C8 / C18) alkylpolyglycoside, and in particular a (C8-C16) alkylpolyglycoside.

[0062] A mixture of APGs of alkyl chain length is generally used. They are denoted Ca / Cb, a and b denoting the number of carbon atoms in the alkyl chain. The following mixtures are particularly suitable: a (C8 / Ci0) alkylpolyglycoside, a (Cio / Ci2) alkylpolyglycoside or a (Cio / Ci6) alkylpolyglycoside.

[0063] In embodiments, the weight ratio of the second non-ionic surfactant to said biocidal active substance is between 0.5 and 200%, in particular between 2 and 50%.

[0064] In embodiments, the first non-ionic surfactant represents from 15% to 90% by weight, in particular from 25% to 55% by weight of the total weight of the non-ionic surfactants present in the formulation.

[0065] In embodiments, the weight ratio of said first surfactant to said second non-ionic surfactant is between 15 and 500%, in particular from 55% to 200%.

[0066] In embodiments, the weight ratio of non-ionic surfactants to said active substance is between 5 and 200%, and more particularly between 15% and 100%.

[0067] Anionic surfactants

[0068] The biocidal formulations according to the invention comprise an anionic surfactant.

[0069] In embodiments, the weight ratio of said anionic surfactant to said biocidal active substance is between 20% and 200%, in particular between 50% and 100%.

[0070] Preferably, the anionic surfactant is chosen from biodegradable anionic surfactants and / or those derived from renewable resources, in particular plant-based ones.

[0071] In embodiments, the anionic surfactant comprises at least one carboxylate surfactant, in particular 2-(2-octoxyethoxy)acetic acid or its sodium salt.

[0072] In embodiments, the anionic surfactant comprises a sulfate-type anionic surfactant, in particular having a C8-C20 alkyl or alkoxy chain, in particular sodium lauryl sulfate, or a sodium (C8-C16) alkyl ether sulfate.

[0073] Other ingredients

[0074] The biocidal formulation according to the invention may further comprise a pH adjusting agent, a thickening agent, a colorant, an emollient, a perfume or a mixture thereof.

[0075] These ingredients may represent in total from 0% to 3% of the total weight of the formulation.

[0076] In embodiments, the biocidal formulation according to the invention comprises from 25% to 99.1%, in particular from 35 to 98% of water.

[0077] Diluted, ready-to-use biocidal formulations

[0078] The formulations according to the invention may include concentrated formulations, to be diluted in water to form ready-to-use formulations, or use solutions making it possible to obtain the desired cleaning and biocidal efficacy when directly brought into contact with the surface to be cleaned.

[0079] In embodiments, the formulation comprises: - from 0.2% to 2.5% by weight of at least one biocidal active substance, the active substance being an organic acid, CrC8, in particular an alpha hydroxy carboxylic acid; - from 0.1% to 5% by weight, in particular from 0.3% to 2% by weight, of at least one anionic surfactant, in particular chosen from carboxylates, sulfates or mixtures thereof; -from 0.09% to 4% by weight, in particular from 0.1% to 2% by weight of non-ionic surfactants, comprising: - a first non-ionic surfactant having a (C3-C7) alkyl chain, - a second non-ionic surfactant having a (C8-C20) alkyl chain; said formulation being ready for use.

[0080] In embodiments of the ready-to-use formulation, the first non-ionic surfactant represents from 0.009% to 1.8% by weight, in particular from 0.02% to 0.9% by weight of the total weight of the formulation.

[0081] In embodiments, the second non-ionic surfactant represents from 0.08% to 2% by weight of the total weight of the formulation.

[0082] In embodiments, the ready-to-use formulation is obtained by diluting a more concentrated formulation with water, in particular in a ratio of 0.1 to 25% by weight (of the concentrated formulation in water), in particular 0.5 to 10% by weight, more specifically 0.5 to 5% by weight.

[0083] Concentrated biocidal formulations, to be diluted

[0084] In embodiments, the formulation comprises: - from 5% to 30% by weight of at least one biocidal active substance, the active substance being or comprising a CrC8 organic acid, in particular an alpha hydroxy carboxylic acid; - from 5% to 30% by weight, in particular from 15% to 30% by weight, of at least one anionic surfactant, in particular chosen from carboxylates, sulfates or mixtures thereof; -from 1% to 12% by weight, in particular from 2% to 8% by weight of non-ionic surfactants, comprising: - a first non-ionic surfactant having a (C3-C7) alkyl chain, - a second non-ionic surfactant having a (C8-C20) alkyl chain; said formulation being a concentrated formulation.

[0085] Use of biocidal formulations

[0086] According to a second aspect, the invention relates to the use of a biocidal formulation according to the invention, for cleaning and disinfecting inanimate hard surfaces, including surfaces in contact with food; for human hygiene, in particular for disinfectant hand washing; cleaning and disinfecting the teats of animals before or after milking; cleaning and disinfecting fruits and vegetables. Examples

[0087] Preparation of formulations

[0088] The formulations are prepared by adding the different ingredients to fresh water (6°TH) at 22°C (+ / - 3°C) according to the following table 1.

[0089] [Tab 1] Comparative Formula A Comparative Formula B Comparative Formula C Comparative Formula D Invention Water (% w / w) 98.9 96.9 96.9 96.9 Lactic acid (% w / 0.6 0.6 0.6 0.6 w) Anionic TA (% w / w) 0.4 0.4 0.4 0.4 APG in Ci2 (% w / w) 0 2 0 0.75 APG in C5 (% w / w) 0 0 2 1.25 Perfume (% w / w) 0.1 0.1 0.1 0.1

[0090] The biocidal activity, the degreasing cleaning power and the stability of the formulations are evaluated.

[0091] Biocidal activity

[0092] The formulations are tested according to the NF EN 1276 (2019) standard to measure bactericidal activity and according to the NF EN 1650 (2019) standard to measure le-vuricidal activity.

[0093] The formulations are ready to use and evaluated at a concentration of 80% (v / v) as recommended in the protocols of the corresponding standards. The tests are carried out with the model strains of Escherichia coli ATCC 10536, Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa ATCC 15442 and Enterococcus hirae ATCC 10541 for bactericidal activity as well as the strain Candida albicans ATCC 10231 for yeasticidal activity.

[0094] The strains are brought into contact with an interfering substance, bovine albumin (fraction V) at 3g / L, which represents dirty conditions defined in the 2 standards.

[0095] The biocidal formulation is then added and left in contact with the microbial strain / interfering substance mixture for a period of 5 minutes (± 10 seconds) at 20°C (± 1°C). At the end of the contact time, the biocidal activity is neutralized using the dilution / neutralization method. The neutralizer is prepared in distilled water and is composed of sodium thiosulfate at 5 g / L, soy lecithin at 3 g / L, polysorbate 80 at 30 g / L and phosphate buffer (0.25 mol / L) at 100 g / L. The surviving microorganisms are counted by deep spreading of the neutralized mixture, after 24 h at 37°C (± 1°C) for bactericidal activity and 48 h at 30°C (± 1°C) for yeasticidal activity, respectively on TSA and GEM medium, in order to calculate a logarithmic reduction compared to the initial concentration of microorganisms in the test. The results are reported in Table 2 below.

[0096] [Tab 2] Formula A Formula B Formula C Formula D Bactericidal activity ++ ++ ++ ++ Yeasticidal activity ++ + ++ ++

[0097] In the table, -the ++ note indicates that a microbial logarithmic reduction greater than 5, -the + note indicates a microbial logarithmic reduction greater than 3.

[0098] The results show that the tested formulations meet the acceptance criteria of EN 1276:2019. Formulations A, C and D meet the acceptance criteria of EN 1650:2019.

[0099] These results show that formulation B comprising a long-chain non-ionic surfactant, as the only non-ionic surfactant in the formulation, exhibits less effective yeasticidal activity than the activities observed for formulations A, C and D. Formulation B is therefore discarded for further testing.

[0100] The degreasing cleaning power and stability of formulations A, C and D, exhibiting improved biocidal activities, are then evaluated.

[0101] Degreasing cleaning power:

[0102] The degreasing cleaning power of the different formulas was evaluated according to the so-called “abrasimeter” method described by the “German Cosmetic, Toiletry, Perfumery and Detergent Association (IKW)” and published in SOFW Journal, Volume 144 (2018), with the following modifications:

[0103] The supports used are 46x33 cm glass plates covered with a glossy white adhesive film.

[0104] The surface is first cleaned with a 70% (v / v) ethanol solution and then left to dry for 1 hour.

[0105] A mixture of dirt is then applied to the surface. This is a colored hydro-alcoholic composition based on fatty and protein foods.

[0106] The soil mixture is heated with slow stirring to 70°C for 10 min before being cooled to room temperature.

[0107] The soiling is heated to 50°C before being applied uniformly (3 mg / cm2) over the entire surface to be tested using a foam roller.

[0108] Leave to dry for 12 hours at room temperature (22°C + / - 3°C)

[0109] The surfaces are then cleaned with an abraser (TQC Dry Washability Tester - model AB5210) with sponges (Spontex® Azela 86 9x4 cm) previously rinsed 3 times in clean water, then impregnated uniformly with 30g of product to be tested.

[0110] A check is carried out by replacing the product to be tested with water (6°TH).

[0111] The sponges are installed on the abraser and a weight of 100g is applied to each sponge in accordance with the manufacturer's instructions.

[0112] Cleaning is carried out using the abraser for 5 round trips, at the speed of 35 cycles / min.

[0113] The cleaning power is assessed by visual rating from 0 to 5 according to a pre-defined scale, with a score of 5 indicating total removal of the dirt and a score of 0 indicating removal similar to the water test. The tests are repeated at least 5 times for each product tested so that the average of the results per product can be calculated.

[0114] The results are reported in [Fig. 1]. The results show that formulation D according to the invention has a cleaning and degreasing power at least 50% greater than comparative formulations A and C.

[0115] Stability

[0116] The stability of the formulas is evaluated according to the CIP AC MT 46.3 “Accelerated Storage Procedure” method by placing the different formulas in glass bottles for 14 days at 54°C (+ / -1°C). The appearance of the formulas is then visually evaluated once the samples have returned to room temperature (22+ / - 3°C).

[0117] The results are reported in [Fig.2]. The bottles were photographed. The results show that the formulation according to the invention D is clear unlike formulations A and C, which are opaque.

[0118] In conclusion, the formulation according to the invention comprising this combination of non-ionic surfactants has an improved biocidal activity compared to formulation B comprising only a long-chain non-ionic surfactant as non-ionic surfactant. In addition, the formulation according to the invention has an improved degreasing cleaning power and stability compared to formulation A, which does not comprise a non-ionic surfactant and compared to formulation C, which comprises an anionic surfactant and a short-chain non-ionic surfactant.

[0119] Thus, the presence of a combination of specific non-ionic surfactants makes it possible to improve each of the properties tested.

Claims

Claims

1. A biocidal formulation comprising: • from 0.2% to 30% by weight relative to the total weight of the formulation of at least one biocidal active substance, the active substance being or comprising a C1-C8 organic acid, in particular an alpha hydroxy carboxylic acid; • from 0.1% to 30% by weight relative to the total weight of the formulation, of at least one anionic surfactant, in particular chosen from carboxylates, sulfates or mixtures thereof; • from 0.09% to 15% by weight relative to the total weight of the formulation of non-ionic surfactants comprising: - a first non-ionic surfactant having a (C3-C7) alkyl chain, and - a second non-ionic surfactant having a (C8-C20) alkyl chain; in which the weight ratio expressed as a percentage of said first non-ionic surfactant to said biocidal active substance is between 5% and 200%, in particular between 15 and 100%.

2. A formulation according to claim 1, wherein the CrC8 organic acid is selected from formic acid, lactic acid, citric acid, tartaric acid, glycolic acid, malic acid, maleic acid, fumaric acid, adipic acid, and succinic acid or a mixture thereof, in particular citric acid, lactic acid, tartaric acid, and malic acid or a mixture thereof.

3. Formulation according to claim 1 or 2, in which the nonionic surfactants are chosen from alkylpolyglycosides, ethoxylated or non-ethoxylated sorbitan esters, ethoxylated or non-ethoxylated polyglycerol esters, ethoxylated alcohols, ethoxylated oils, or mixtures thereof.

4. Formulation according to claim 1 to 3, wherein the first and / or second non-ionic surfactant is / are an alkylpolyglycoside.

5. A formulation according to any preceding claim, wherein said first non-ionic surfactant is a (C3-C7) alkylpolyglycoside, in particular a (C5-C6) alkylpolyglycoside.

6. Formulation according to claim 5, wherein the first ten- Non-ionic sioactive is a D-xylopyranose (C3-C7) alkyl glycoside, notably D-xylopyranose 3-methylbutyl glycoside.

7. A formulation according to any preceding claim, wherein the second non-ionic surfactant is a (C8-C2o) alkyl polyglycoside, in particular a (C8-C16) alkyl polyglycoside.

8. Formulation according to any one of the preceding claims, in which the weight ratio expressed as a percentage of the second non-ionic surfactant to said biocidal active substance is between 0.5 and 200%, in particular between 2 and 50%.

9. Formulation according to any one of the preceding claims, wherein the first non-ionic surfactant represents from 15% to 90% by weight, in particular from 25% to 55% by weight of the total weight of the non-ionic surfactants present in the formulation.

10. Formulation according to any one of the preceding claims, wherein the weight ratio expressed as a percentage of said first surfactant to said second non-ionic surfactant is between 15 and 500%, in particular from 55% to 200%.

11. Formulation according to any one of the preceding claims, in which the weight ratio expressed as a percentage of non-ionic surfactants to said active substance is between 5 and 200%, and more particularly between 15% and 100%.

12. Formulation according to any one of the preceding claims, wherein the weight ratio expressed as a percentage of said anionic surfactant to said biocidal active substance is between 20% and 200%, in particular between 50% and 100%.

13. A formulation according to any preceding claim, wherein the anionic surfactant comprises at least one carboxylate surfactant, in particular 2-(2-octoxyethoxy)acetic acid or its sodium salt.

14. Formulation of any one of the preceding claims, wherein the anionic surfactant comprises a sulfate-type anionic surfactant, in particular having a C8-C20 alkyl or alkoxy chain, in particular sodium lauryl sulfate, or a sodium (C8-C16) alkyl ether sulfate.

15. A formulation according to any preceding claim, wherein the biocidal active substance of the formulation consists of a single organic acid, which is either lactic acid or citric acid, preferably lactic acid.

16. A formulation according to any preceding claim, wherein the formulation further comprises a pH adjusting agent, a thickening agent, a colorant, an emollient, a perfume or a mixture thereof.

17. Formulation according to any one of claims 1 to 16, comprising: • from 5% to 30% by weight relative to the total weight of the formulation of at least one biocidal active substance, the active substance being or comprising a C1-C8 organic acid, in particular an alpha hydroxy carboxylic acid; • from 5% to 30% by weight relative to the total weight of the formulation, in particular from 15% to 30% by weight, of at least one anionic surfactant, in particular chosen from carboxylates, sulfates or mixtures thereof; • from 1% to 12% by weight relative to the total weight of the formulation, in particular from 2% to 8% by weight of non-ionic surfactants, comprising: - a first non-ionic surfactant having a (C3-C7) alkyl chain, - a second non-ionic surfactant having a (C8-C20) alkyl chain; said formulation being a so-called concentrated formulation.

18. Formulation according to any one of claims 1 to 16, comprising: • from 0.2% to 2.5% by weight relative to the total weight of the formulation of at least one biocidal active substance, the active substance being an organic acid, CrC8, in particular an alpha hydroxy carboxylic acid; • from 0.1% to 5% by weight relative to the total weight of the formulation, in particular from 0.3% to 2% by weight, of at least one anionic surfactant, in particular chosen from carboxylates, sulfates or mixtures thereof; • from 0.09% to 4% by weight relative to the total weight of the formulation, in particular from 0.1% to 2% by weight of non-ionic surfactants, comprising: - a first non-ionic surfactant having a chain (C3-C7) alkyl, - a second non-ionic surfactant having a (C8-C20) alkyl chain; said formulation being ready for use.

19. Formulation according to claim 18, in which the first non-ionic surfactant represents from 0.009% to 1.8% by weight, in particular from 0.02% to 0.9% by weight relative to the total weight of the formulation.

20. A formulation according to any one of claims 18 or 19, wherein the second non-ionic surfactant represents from 0.08% to 2% by weight relative to the total weight of the formulation.

21. Formulation according to any one of claims 18 to 20, wherein the ready-to-use formulation is obtained by diluting a formulation as defined in claim 17 with water, in particular in a ratio of 0.1 to 25% by weight (of the concentrated formulation in water), in particular 0.5 to 10% by weight, more specifically 0.5 to 5% by weight.

22. Formulation according to any one of the preceding claims, wherein more than 50% by weight, preferably more than 75% by weight, especially more than 95% by weight of the ingredients of the formulation are of renewable origin.

23. Formulation according to any one of the preceding claims, characterized in that it is biodegradable to more than 95%, in particular to more than 98% according to the OECD 301 guidelines.

24. Use of a biocidal formulation according to any one of claims 1 to 23, for cleaning and disinfecting inanimate hard surfaces, including surfaces in contact with food; for human hygiene, in particular for disinfectant hand washing; cleaning and disinfecting the teats of animals before or after milking; cleaning and disinfecting fruits and vegetables.

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