AQUEOUS ODOR ABSORBING COMPOSITION

Abstract: The invention relates to an aqueous odor absorbing composition comprising 1.8 - 14 % per weight betacyclodextrin, 0.1 - 11 % by weight of a water soluble carboxylic acid and 0.1 - 0.3 % per weight of an antimicrobial preservative. The aqueous odor absorbing composition of the invention may be used in the air or any surface with the exception of humans.

Description: Aqueous Odor Absorbing Composition The present invention relates to an aqueous odor absorbing composition for use in the air and on surfaces except for use directly on humans. A wide variety of compositions are used to control odor especially malodor. Such compositions comprise perfumes, colognes, active compounds which react with malodor, compounds comprising antibacterial and antifungal agents etc. WO96/04937 discloses an odor control composition consisting of an aqueous solution comprising '. ater-soluble cyclocextnns, antimicrobial preservatives and optionally a perfume. The cyclodextrins used are alpha-, beta- and gamma- cyclodextrins consisting of glucose units arranged in a donut-shaped ring which forms inclusion complexes with organic molecules e.g. those of malodors. Betacyclodextrin is preferred for aiodor-absorption due to its ring size and low cost, however, having a solubility limit of about 1.85 % at room temperature it can only be used in a concentration of up to this limit. For desirable higher concentration betacyclodextrin is derivatised. In such derivatives some of the OH-groups of beta-cyclodextrir. are converted to OR-groups. Tr.e known compositions are used for malodor- absorpt on or -control on textiles by spraying. The US-A-5 6?7 854, US-A-5 879 66 and US-A-5 534 165 also descnoe the use of cloαextnns for odor absorption. Beta-cyclodextrin s used in all cases either m a concentration up to ts solubility limit of 1.85% cr, f higher concentration is desired, in a derivatised form. The solutions of the above documents comprise also antimicrobial preservatives. The solubility of the latter is improved, if desired, by the addition of small amounts of 0.001 to 0.3% of a chelating agent. One object of the present invention is to provide a novel malodor-absorbing composition having a high malodor-control . A further object of the present invention is to provide an aqueous malodor-absorbing composition with a low level of olfactive compounds. A further object of the present invention is to provide an aqueous malodor absorbing composition with a high concentration of beta-cyclodextrin. A further object of the present invention is to provide an aqueous malodor-absorbing composition with a low viscosity and therefore with good spraying quality. It has been surprisingly found that addition of carboxylic acids to an aqueous solution multiplies the solubility of non-derivatised beta-cyclodextrin. Therefore, the present invention refers to an aqueous odor absorbing composition comprising a cyclodextrin and an antimicrobial preservative characterized by 1.8 to 14 % by weight of the total composition of beta-cyclodextrin 0.1 to 11 % by weight of the total composition of a water-soluble carboxylic acid and 0.1 to 0.3 % by weight of the total composition of the antimicrobial preservative, whereby all three components are in solution. Carboxylic acids which enhance the solubility of beta- cyclodextrin are carboxylic monoacids and polyacids which may be substituted by one or more hydroxy groups such as glycolic acid, lactic acid, malonic acid, malic acid, glutaric acid, diglycolic acid, succinic acid, citramalic acid, tartaric acid, mucic acid, adipic acid and derivatives thereof. The preferred carboxylic acids are hydroxy-carboxylic polyacids such as citric acid, which may be present in an amount of 1 to 8 % preferably in an amount of 6 % per weight of the total composition. Due to the surprising solubilizing effect of the carboxylic acid compositions according to the present invention may comprise up to 14 % of beta- cylcodextrins, amounts of 1.85 to 10 % give good results and amounts of 1.9 to 6 % are preferred. Antimicrobial preservatives are useful for stabilizing the composition of the invention. Preferred antimicrobial water soluble preservatives are paraben, phenyl and phenoxy compounds such as phenyl ethanol, phenoxyethanol, organic nitrogen compounds such as imidazolidinyl urea, organic sulfur compounds such as 5-chloro-2-methyl-4-isothiazolin-3-one and 2- methyl-4-isothiazolin-3-one, halogenated compounds such as chlorobutanol, trichlorohydroxy-diphenylether, parachlorometa-cresol, metallic salts such as copper salts and zinc salts e.g. ZnCl 2 . The amount of beta-cyclodextrin disolved in the compositions of the present invention alone is sufficient to control malodor in an appreciable extent, however, olfactive compounds can be added to impart pleasant odors to a substrate the composition is applied to. Small amounts of olfactive compounds give surprisingly good results i.e. additionally improving control of malodor and adding a pleasant odor at the use of the compositions of the present invention. Further solubilizing agents for the olfactive compounds, such as fragrances, may be added. Such solubilizing agents are nonionic, anionic, cationic and amphoteric surfactants. Nonionic surfactants are block copolymers, graft copolymers and homopolymers all being more hydrophylic than hydrophobic. Preferred anionic surfactants are alkyl sulfonate. Such solubilizing agents may be present in an amount of 0.01 to 5 % preferably 0.01 to 4 %. The compositions of the invention may be used to control odor especially malodor in the environment (air-freshener) and on any structured surface such as textiles, rugs, walls etc. In liquid form they may be sprayed or if containing a thickener and thus having a higher viscosity applied with conventional means such as a paintbrush. The invention is further described in the examples. Examples 1 to 11 The ingredients given in Table I and II are r.ixed and dissolved to form a clear solution. Table I Perfume is a composition of the following 15 compounds: amylacetate, eucalyptol, dymethyloctenon, Cyclal C, linalool, Aldehyde C12 MNA, viridine, terpineol, benzylacetat, irisone, verdylaceta , phenyl ethyl alcohol, diphenyloxid, prunolide, lilial. Table II Perfume 2* is a composition of the following 15 compounds: limonen, tetrahydrolinalool, dihydromyrcenol, anethol, citronellol, alpha-methyl ionone, phenyl ethyl alcohol, lilial, γ-nonalacton, vertofix, γ-decalactone, methyldihydrojasmonale, cumarin, verdyl-propionate, verdylacetat . In a first set of evaluation the malodor control or coverage is evaluated directly in the gas phase against tobacco and kitchen malodors by a panel of 4 trained individuals. The panelist evaluate systems with different beta-cyclodextrin concentrations of Examples 1-11 at a constant concentration of malodor. The results are shown in Table III. The best malodor control is denoted by 3. Table III In a second set of evaluation the malodor control is evaluated in situ by a group of 10 trained individuals. The compositions are sprayed on a fabric with tobacco malodor. Fabrics sprayed with the compositions and unsprayed fabrics are compared. The results are shown in Table IV. Table IV

Claims: Claims 1. An aqueous odor absorbing composition comprising a cyclodextrin and an antimicrobial preservative characterized by 1.8 to 14 % by weight of the total composition of beta-cyclodextrin 0.1 to 11 % by weight of the total composition of a water-soluble carboxylic acid and 0.1 to 0.3 % by weight of the total composition of the antimicrobial preservative, whereby all three components are in solution. 2. Composition according to claim 1 wherein the carboxylic acid is a carboxylic monoacid which may be substituted by a hydroxy group. 3. Composition according to claim 1 wherein the carboxylic acid is a carboxylic polyacid which may be substituted by one or more hydroxy groups. 4. Composition according to claim 1 wherein the carboxylic acid is selected from a group consisting of glycolic acid, lactic acid, malonic acid, malic acid, glutaric acid, diglycolic acid, succinic acid, citramalic acid, tartaric acid, mucic acid, adipic acid and polyacrylic acid or derivatives thereof. 5. Composition according to claim 3 wherein the carboxylic polyacid is citric acid in an amount of 1 to 8 % per weight of the total composition. 6. Composition according to one of the preceding claims comprising 1.85 to 10 % per weight of the total composition of beta-cyclodextrin. 7. Composition according to claim 6 comprising 1.9 to 6 % per weight of beta-cyclodextrin. 8. Composition according to any of the preceding claims comprising 0.001 to 1 % per weight of the total composition of a fragrance or fragrance composition. 9. Composition according to any of the preceding claims comprising 0.01 to 5 % per weight of the total composition of a solubilizing agent for the fragrance or fragrance composition. 10. Composition according to claim 1 comprising 0.0002 to 0.2 % per weight of the total composition of the antimicrobial preservative. 11. Composition according to anyone of the preceding claims in liquid form. 12. Composition according to claim 13 in form of a spray. 13. Composition according to any of the preceding claims comprising a thickening agent.

Inventors: DUMAS SANDRINE, QUELLET CHRISTIAN, DUMAS, SANDRINE, QUELLET, CHRISTIAN
Applicants: DUMAS SANDRINE, GIVAUDAN ROURE INT, QUELLET CHRISTIAN, DUMAS, SANDRINE, GIVAUDAN ROURE (INTERNATIONAL) S.A., QUELLET, CHRISTIAN
Application year: 2000
Main classification: A61L9
IPC codes: A01N25, A61L9