EP0813589A1

EP0813589A1 - Hypochlorite cleaners with reduced skin malodor

Info

Publication number: EP0813589A1
Application number: EP96905472A
Authority: EP
Inventors: Henry Cheng Na; Pedro Antonio Rodriguez
Original assignee: Procter and Gamble Co
Current assignee: Procter and Gamble Co
Priority date: 1995-03-03
Filing date: 1996-02-14
Publication date: 1997-12-29
Also published as: JPH11501078A; MX9706670A; CA2213838A1; BR9607630A; AR001140A1; CO4700544A1; AU4921996A; WO1996027652A1

Abstract

Hypochlorite cleaning compositions comprising imidodisulfate, hypochlorite and optionally surfactants, builders, perfumes, abrasives and/or other carrier and adjunct materials that prevent formation of skin malodor when said composition contacts human skin.

Description

HYPOCHLORITE CLEANERS WITH REDUCED SKIN MALODOR

FIELD OF THE INVENTION

The present invention relates to hypochlorite cleaning compositions comprising imidodisufate, hypochlorite and optionally surfactants, builders, perfumes, abrasives and/or other carrier and adjunct materials that prevent formation of skin malodor when said composition contacts human skin. The present invention also relates to a method for cleaning hard surfaces with a composition comprising hypochlorite and imidodisulfate that reduces the formation of malodor on human skin.

BACKGROUND OF THE INVENTION

Hard surface cleaners can be in liquid, solid or viscous semi-solid form. Known liquid, solid and viscous semi-solid hard surface cleaners can comprise detergent surfactants, water and optionally certain organic solvents, builders, buffers, and/or perfumes as well as other adjunct materials. Solid and viscous semi-solid forms of hard surface cleaners may optionally comprise as adjunct ingredients one or several abrasive materials. Solid and viscous semi-solid, hard surface cleaners containing abrasive materials are used primarily as "scouring" agents. It has long been known that abrasive materials can be used in conjunction with hard surface cleaners to remove commonly encountered soils or soap scums.

The inclusion of hypochlorite and hypochlorite generating components into hard surface cleaners has steadily grown. In fact, hypochlorite-containing hard surface cleaners are among the most effective materials available for cleaning since hypochlorite serves both as a strong oxidizer to assist in the chemical degradation, breakup and removal of stains and soils, and also an inexpensive and effective disinfectant. This dual role of hypochlorite (as a bleach and disinfectant) together with its shelf stability and compatibility with other optional ingredients has contributed to the increased use of sodium hypochlorite or other active chlorine precursors, in the formulation of hard surface cleaners.

Kitchen and bathroom sink, tub, shower, toilet bowl and counter top surfaces, including vinyl, acrylic, and marble, are areas which have been the focus for developments in increased hard surface cleaning capacity. These surfaces are subject not only to exogenous bacteria, fungi and mildews endemic to most households, but to pathogens which are derived from urine and feces. Therefore, the inclusion of hypochlorite into these formulations as a strong and versatile disinfectant is an added benefit to consumers.

To insure proper hygiene and sanitary conditions, a formidable cleaning task must be undertaken to remove the undissolved sediments, grease, soap films, scums, hard water scale and rust stains that form on ceramic surfaces, counter tops and bathroom floors during normal usage. Cleaning is especially difficult in the case of hardened and dried soap films, scums, caked-on residues and scaling due to hard water/undissolved dirt where it is necessary to use more than simple wiping to remove the unwanted sediments.

During the use of hypochlorite containing hard surface cleaners, contacting the cleaning solution, which contains active chlorine, with the human skin results in the production of malodor on the skin known as "Bleached Hand" odor. This "Bleached Hand" odor is believed to result from the contact between the hypochlorite bleach and the protein in the skin and differs from the "chlorine odor" of the hypochlorite bleach per se. Because the active ingredients of hard surface cleaners, especially hypochlorite bleach, cannot distinguish between dirt, cleaning utensils and exposed human skin during scouring process, the only protection once afforded the skin was the use of gloves.

It has now been discovered that the inclusion of imidodisulfate into such cleaners with hypochlorite reduces the formation of active chlorine- induced malodors on the skin. The present invention by its effectiveness in controlling hypochlorite derived malodor on the skin, precludes the necessity of gloves or other protection of the exposed skin during cleaning. This also protects against the inadvertent splashing of the solution onto skin such as the face, neck, leg, forearm etc. Also because of the action of the imidodisulfate of the present invention, the exposure of fabric to direct solution is not as damaging as direct exposure to hypochlorite .

It is thus an object of the present invention to prevent the formation of malodors on the skin due from exposure to hypochlorite. It is another object herein to provide a hypochlorite-containing cleaner that will prevent the formation of malodor on exposed skin. Yet another object herein is to provide a cleaning composition which contains imidodisulfate. BACKGROUND ART

Various references relate to hypochlorite and other bleach compositions comprising additional ingredients. See for example U.S. Pat. No. 4,148,742 issued April 10, 1979; U.S. Pat. No. 4,257,906 issued March 24,1981; U.S. Pat. No. 4,088,611 issued May 9, 1978; U.S. Pat. No. 4,201,687 issued May 6, 1980; U.S. Pat. No. 4,233,173 issued November 11, 1980; and Japanese Kokai 63/108099 (Derwent Abs. No. 88- 171056/25).

SUMMARY OF THE INVENTION

The present invention relates to a hard surface cleaning composition comprising hypochlorite, imidodisulfate, and the balance adjunct ingredients, which when contacted with the skin during use prevents hypochlorite derived malodor on skin. These compositions may be solid, viscous semi-solid or liquid.

In its broadest aspect, this invention involves a method of cleaning hard surfaces that eliminates the formation of active chlorine or hypochlorite derived malodor on the skin known also as "Bleached Hand" smell. A cleaning solution containing imidodisulfate and hypochlorite is applied to a hard surface to remove any soil, grease, oily dirt, soap deposits, or soap films, and any purposeful, accidental or incidental contact of said cleaning solution with human skin does not result in formation of malodor.

The present invention hard surface cleaners comprise imidodisulfate of the form MN(S03M)2 where M is a hydrogen or a water soluble cation and mixtures thereof, preferably M is hydrogen or a cation that is a member selected from the group consisting of the alkali metals or alkaline earth metals, or more preferably M is sodium or potassium. The hard surface cleaner of the present invention contains imidodisulfate from about 0.05% to about 50%, preferably from 0.1% to about 20%, more preferably from about 0.5% to about 10%, most preferably from about 0.5% to about 5%, by weight of the composition.

The present invention comprises hypochlorite which may be derived from any standard hypochlorite material normally used as a bleach or disinfectant, and is not limited to sodium hypochlorite. The hard surface cleaner of the present invention contains hypochlorite from about 0.1% to about 25%, preferably from about 0.1 % to about 20%, more preferably from about 0.5% to about 10%, most preferably from about 0.5% to about 5%, by weight of the composition. The present invention comprises optionally detersive surfactants, chelating agents, builders, abrasives, buffers, perfumes, solvents and other suitable adjunct ingredients used alone or in combination which the formulator may find useful in the practice of the present invention.

The present invention provides for a method of cleaning hard surfaces with a composition comprising imidodisulfate, hypochlorite and optionally adjunct ingredients heretofore mentioned. This method comprises contacting by scrubbing or scouring a surface in need of cleaning with a cleaning composition according to the present invention.

All percentages, ratios and proportions herein are by weight, unless otherwise specified. All temperatures are in degrees Celsius (°C) unless otherwise specified. All documents cited are, in relevant part, incorporated herein by reference.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides for a method of cleaning hard surfaces with a composition comprising imidodisulfate, hypochlorite and detersive surfactant wherein the said cleaning composition is applied directly to a soil, stain, scum or other material to be cleaned and mechanical scouring action is applied by the user. The "scouring" is accomplished by contacting a cleaning device with the soil, stain, scum or otherwise dirty surface and the cleaning composition of the present invention with and the hypochlorite containing cleaner when it contacts the fingers, the hand or other exposed skin surface of the user, either by direct contact or by splashing will not produce malodor.

In addition to the imidodisulfate and hypochlorite, the hard surface cleaner compositions herein will typically comprise various detersive and other adjunct ingredients.

What is meant by contacting the hypochlorite solution of the present invention with the soil, scum, stain or other object or surface to be cleaned is hereby not limited to the application of the composition directly to the object to be cleaned, but the composition can instead be applied to a sponge, pad, brush, cloth or other devise normally used to facilitate the contacting of a cleaning composition with the area to be cleaned.

What is meant by contacting the hypochlorite solution of the present invention with human skin is the splashing onto the skin surface, immersion of the hand, arm or other body part into a solution containing the composition of the present invention, whether by accident or purposefully, especially in the normal course of cleaning. The tissue of the eye is excluded as is the tissue of the mouth excluded. The prudent, safe and intended malodor protection of the hypochlorite cleaning solution of the present invention excludes exposure of the composition to the eye, the mouth or other internal organs including cuts, lesions or other breaks in the skin normally not exposed during common use of cleaning solutions.

The imidodisulfate of the present invention, especially in the solid and viscous semi-solid embodiments, need not be present in an amount necessary to prevent malodor on a basis of stoichiometry or other chemical theory. Excess imidodisulfate can serve as a mechanical abrasive, such as perlite and carbonate, and thereby allow the formulator the option of excluding additional ingredients when an abrasive is needed. Also imidodisulfate can be used in excess to serve as a builder or a chelator of "hard" cations, namely, calcium and magnesium, and thereby offer a "boost" to the surface activity of any detersive surfactants that may be present in a chosen embodiment.

While not intending to be limited by theory, the principle component of "Bleached Hand" malodor on the skin is 1-pyrroline. This material is formed from the amino acid L-proline when the keratin protein found in the stratum corneum layers of the skin is exposed to hypochlorite. The rate of formation and the amount of 1-pyrroline that is formed varies from individual to individual but the general mechanism of formation is believed to be universal. The degradation of skin protein is believed to begin with the rapid, irreversible chlorination of a protein amide bond nitrogen when the skin is exposed to solutions containing hypochlorite. If this N-chlorination occurs adjacent to the amino acid L-proline, the ensuing protein fragmentation results in the formation of 1-pyrroline. The rate of protein degradation, once the N-chlorination has occurred is variable from individual to individual and, in some cases, formation of malodor on the skin continues for several days after exposure to hypochlorite.

It has now been discovered that the inclusion of imidodisulfate into cleaners with hypochlorite reduces the formation of active chlorine induced malodors on the skin.

The inclusion of imidodisulfonate into hypochlorite solid or viscous semi-solid hard surface cleaners can serve an additional role different from that in controlling malodor. Solid imidodisulfate or the appropriate salt can be formulated into a hypochlorite containing solid or viscous semi-solid cleaner to serve as a water soluble abrasive.

The hard surface cleaner of the present invention optionally contains builders, examples of which are, silicates, carbonates, and zeolites, however the user is not limited to these examples or combinations thereof. The builders are present from about 0% to about 50%, preferably from about 5% to about 30%, by weight of the composition.

The hard surface cleaner of the present invention optionally contains abrasives from about 0.5% to about 85%, preferably from about 10% to about 85%, by weight of the composition. Suitable abrasives are silicates, carbonates, perlite, clay, and pulverized ceramic clay, however, the user is not restricted to these examples or combinations thereof.

ADJUNCT MATERIALS

The compositions herein can optionally include one or more other detergent adjunct materials or other materials for assisting or enhancing cleaning performance, treatment of the surface to be cleaned, or to modify the aesthetics of the composition (e.g., perfumes, colorants, dyes, etc.). The following are illustrative examples of such adjunct materials but are not meant to be exclusive or limiting in scope.

Surfactant - The instant cleaning compositions contain from about 0.1 % to about 60% by weight of a surfactant selected from the group consisting of anionic, nonionic, ampholytic and zwitterinonic surface active agents. For liquid systems, surfactant is preferably present to the extent of from about 0.1 % to 20% by weight of the composition. For solid (i.e. granular) and viscous semi-solid (i.e. gelatinous, pastes, etc.) systems, surfactant is preferably present to the extent of from about 1.5% to 30 % by weight of the composition.

Anionic surfactants can be broadly described as the water-soluble salts, particularly the alkali metal salts, of organic sulfuric reaction products having in their molecular structure an alkyl radical containing from about 8 to about 22 carbon atoms and a radical selected from the group consisting of sulfonic acid and sulfuric acid ester radicals. (Included in the term alkyl is the alkyl portion of higher acyl radicals.) Important examples of the anionic synthetic detergents which can form the surfactant component of the compositions of the present invention are the sodium or potassium alkyl sulfates, especially those obtained by sulfating the higher alcohols (C8-18 carbon atoms) produced by reducing the glycerides of tallow or coconut oil; sodium or potassium alkyl benzene sulfonates, in whcih the alkyl group contains from about 9 to about 15 carbon atoms, (the alkyl radical can be a straight or branched aliphatic chain); sodium alkyl glyceryl ether sulfonates, especially those ethers of the higher alcohols derived from tallow and coconut oil; sodium coconut oil fatty acid monoglyceride sulfates and sulfonates; sodium or potassium salts of sulfuric acid ester of the reaction product of one mole of a higher fatty alcohol (e.g. tallow or coconut alcohols) and about 1 to about 10 moles of ethylene oxide; sodium or potassium salts of alkyl phenol ethylene oxide ether sulfates with about 1 to about 10 units of ethylene oxide per molecule and in which the alkyl radicals contain from 8 to 12 carbon atoms; the reaction products of fatty acids are derived from coconut oil sodium or potassium salts of tatty acid amides of a methyl tauride in which the fatty acids, for example, are derived from coconut oil and sodium or potassium beta-acetoxy- or beta-acetamido- alkanesulfonates where the aikane has from 8 to 22 carbon atoms.

Additionally, secondary alkyl sulfates may be used by the formulator exclusively or in conjunction with other surfactant materials and the following identifies and illustrates the differences between sulfated surfactants and otherwise conventional alkyl sulfate surfactants. Non- limiting examples of such ingredients are as follows.

Conventional primary alkyl sulfates, such as those illustrated above, have the general formula ROS03-M+ wherein R is typically a linear C8-22 hydrocarbyl group and M is a water solublizing cation. Branched chain primary alkyl sulfate surfactants (i.e., branched-chain "PAS") having 8-20 carbon atoms are also known; see, for example, Eur. Pat. Appl. 439,316, Smith et al., filed January 21 , 1991.

Conventional secondary alkyl sulfate surfactants are those materials which have the sulfate moiety distributed randomly along the hydrocarbyl "backbone" of the molecule. Such materials may be depicted by the structure

CH₃(CH2)n(CHOSθ3-M⁺)(CH2)_mCH₃ wherein m and n are integers of 2 of greater and the sum of m + n is typically about 9 to 17, and M is a water-solublizing cation.

In addition, the selected secondary (2,3) alkyl sulfate surfactants used herein may comprise structures of formulas I and II

CH3(CH2)_χ(CHOS0₃-M⁺)CH3 I CH₃(CH₂)y(CHOSθ3-M⁺)CH2CH3 II for the 2-suifate and 3-sulfate, respectively. Mixtures of the 2- and 3-sulfate can be used herein. In formulas I and II, x and (y+1) are, respectively, integers of at least about 6, and can range from about 7 to about 20, preferably about 10 to about 16. M is a cation, such as an alkali metal, ammonium, alkanolammonium, triethanol-ammonium, potassium, ammonium, and the like, can also be used.

The aforementioned secondary alkyl sulfates are those prepared by the addition of H2SO4 to olefins. A typical synthesis using alpha olefins and sulfuric acid is disclosed in U.S. Pat. No. 3,234,258, Morris, issued February 8, 1966 or in U.S. Pat. No. 5,075,041 , Lutz, issued December 24,1991. The synthesis conducted in solvents which afford the secondary (2,3) alkyl sulfates on cooling, yields products whcih, when purified to remove the unreacted materials, randomly sulfated materials, unsulfated by¬ products such as C10 and higher alcohols, secondary olefm sulfonates, and the like, are typically 90 + % pure mixtures of 2- and 3- sulfated materials (some sodium sulfate may be present) and are white, non tacky, apparently crystalline, solids. Some 2,3-disulfates may also be present, but generally comprise no more than 5 % of the mixture of secondary (2,3) alkyl mono- sulfates. Such materials are available as under the name "DAN", e.g., "DAN 200" from Shell Oil Company.

Buffers - Buffers can be included in the formulations herein for a variety of purposes. One such purpose is to adjust the cleaning surface pH to optimize the hard surface cleaner composition effectiveness relative to a particular type of soil or stain. Buffers may be included to stabilize the adjunct ingredients with respect to extended shelf life or for the purpose of maintaining compatibility between various aesthetic ingredients. The hard surface cleaner of the present invention optionally contains buffers to adjust the pH in a range from about 7 to about 13, preferably from about 8 to about 13, more preferably from about 10 to about 11. Non-limiting examples of such suitable buffers are potassium carbonate, sodium carbonate, and sodium bicarbonate, however, the formulator is not restricted to these examples or combinations thereof.

Chelatinα Aαents - The cleaningcompositions herein may also optionally contain one or more iron and/or manganese chelating agents. Examples of such compatable chelating agents are ethane-1-hydroxy-1,1- diphosphonic acid (EHDP) and dipicolinic acid.

Abrasives. An essential component of many solid or viscous semi- solid hard surface cleaning compositions is the abrasive material added to facilitate the action of scouring. Abrasive scouring cleansers provide a convenient and useful means for carrying out the sanitizing of porcelain and tile surfaces, especially tubs, showers and toilet bowls. The paniculate abrasive material within such compositions serves to abrade and loosen soil adhering to hard surfaces and further serves to create more intimate contact between hard surface stain and the surfactant and/or bleaching agents also present in the cleansing compositions.

Abrasive cleaners have traditionally contained water-insoluble, relatively hard, particulate mineral material as the abrasive agent. The most common such abrasive agent is finely divided silica sand having particle size varying between about 1 and 300 microns and specific gravity of about 2.1 or higher. While such material is generally very effective in scouring soil and stains from the surfaces being treated, abrasive material of this type tends to be difficult to rinse away from the toilet bowl, shower or bathtub surface.

In the case where moderate or highly water soluble abrasive material is required (i.e. sodium carbonate) imidodisulfate can be used as the sole abrasive or otherwise added in part.

It has been discovered that abrasive compositions of this desired type can be realized by utilizing a particular type of expanded perlite abrasive in combination with the surfactants, filler material, and other optional scouring material ingredients listed herein. The abrasive materials suitable to the present invention are those contained in U.S. Pat. No. 4,051,056, Hartman, issued September 27, 1977 and included herein by reference.

Perfumes. Perfumes are an important ingredient especially for the liquid composition embodiment. Perfume is usually used at levels of from 0% to 5%. In U.S. Pat. No. 4,246,129, Kachβr, issued January 20, 1981 (incorporated herein by reference), certain perfume materials are disclosed which perform the added functionreducing the solubility of anionic sulfonate and sulfate surfactants.

Other Adjunct Ingredients. As a preferred embodiment, the conventional adjunct ingredients employed herein can be selected from 652 PCMJS96/01909

10 bleach stabilizers, pigments, color speckles, suds boosters, suds supressors, anti-tamish and/or anti-corrosion agents, soil-suspending agents, germicides, alkalinity sources, hydrotropes, anti-oxidants, clay soil removal/anti-redeposition agents, polymeric dispersing agents, etc. MALODOR EVALUATION PROCEDURES SAMPLE IMMERSION METHOD

1. The hands and forearms of each subject is thoroughly washed with a hand soap, (e.g., IVORY SOAP, available from the Procter & Gamble Co.) Hands are patted dry.

2. Each hand is then submerged into the test solutions up to the wrist and held immersed for a total of 30 seconds.

3 Each hand is then separately rinsed under warm running tap water for 5 seconds.

4. Each hand is then patted dry with separate towels.

5. Each hand is then evaluated by panelists at periods of 0, 15, 30, 45, 60, and 120 minutes.

SAMPLE APPLICATION METHOD

2. To the back or palm of each hand is applied 3 mL of the solution to be tested. The solution is allowed to spread over the surface of the skin for 30 seconds.

3. Each hand is then rinsed with running 80° F tap water for 5 seconds.

4. Each hand is then patted dry with separate towels.

EXAMPLES OF IMIDODISULFATE

CONTAINING COMPOSITIONS

The following table lists examples of the direct application of the present invention for the control of malodor or human skin exposed to compositions comprising hypochlorite or hypochlorite forming ingredients.

Quantities on a weight % basis Component Example No.

1 2 3 4 5 6 potassium imidodisulfate 4.1 5.7 4.5 5.0 12.5 3.0

11 sodium hypochlorite 0.9 1.6 1.6 _ „_» „, calcium hypochlorite - - - - 2.2 - sodium dichlorocyanurate - - - 3.4 - 2.1 surfactant 0.25 3.6 5.3 6.5 6.1 9.5 tetrapotassium 6.0 - 2.0 - 13.0 - pyrophosphate tripotassium phosphate 2.0 - 20.5 - 12.0 - sodium tripolyphosphate - - 20.0 - - - sodium silicate - 0.04 - - 0.5 - sodium periodate - 0.01 - - - - sodium acetate - - - 14.7 - - calcium oxide - - - 2.0 2.8 - alkali metal carbonate - - - 36.7 27.5 1.1 perlite abrasive 6.5 - 25.0 28.5 22.5 0.5 dye and perfume 0.75 0.28 - - 0.7 - miscellaneous - - 10.2 - - 22.6 lanolin - - - - - 2.1 carboxymethylcellulose - - - - - 2.6 moisture/distilled water bal. bal. bal. bal. bal. bal.

Use of these hard surface cleaning compositions comprising imidodisulfate substantially reduces the formation of malodor associated with the exposure of human skin to hypochlorite when the skin is contacted with said solution.

WHAT IS CLAIMED IS:

Claims

1. A bleach containing cleaning composition which avoids the formation of malodor on skin, comprising:

(a) at least 0.05%, by weight of imidodisulfate;

(b) from 0.1% to 25%, by weight, of hypochlorite; and

(c) the balance comprising carrier and adjunct ingredients.

2. A composition according to Claim 1 wherein said imidodisulfate has the formula N(Sθ3M)2 where M is a member selected from the group consisting of hydrogen, water soluble cations and mixtures thereof, preferably alkali metal cations, alkaline earth metal cations, ammonium cations, and mixtures thereof, and more preferably sodium, potassium or mixtures thereof.

3. A composition according to either of Claims 1 or 2 comprising from 0.5% to 5%, by weight, of imidodisulfate.

4. A composition according to any of Claims 1 - 3 comprising from 0.5% to 5%, by weight, of hypochlorite.

5. A composition according to any of Claims 1 - 4 wherein said adjunct ingredient is a member selected from the group consisting of perfumes, abrasives, chelants, buffers, surfactants, filler salts and mixtures thereof.

6. A composition according to any of Claims 1 - 5 comprising buffers in an amount adequate to produce a pH from 7 to 13.

7. A composition according to any of Claims 1 - 6 comprising from 0.1 % to 60%, by weight, of a surfactant.

8. A composition according to any of Claims 1 - 7 comprising from 0.5% to 85%, by weight, of an abrasive that is a member selected from the group consisting of silicates, carbonates, perlite, clay, pulverized ceramic clay, and mixtures thereof.

9. A method for cleaning hard surfaces, said method comprising contacting by scrubbing or scouring a surface in need of cleaning with a cleaning composition according to any of Claims 1 - 8.