AU688356B2

AU688356B2 - A process of cleaning carpets using active oxygen compounds in an acidic aqueous medium

Info

Publication number: AU688356B2
Application number: AU74034/94A
Authority: AU
Inventors: Axel Koenig; Stefano Scialla; Andrea Soddu
Original assignee: Procter and Gamble Co
Current assignee: Procter and Gamble Co
Priority date: 1993-08-03
Filing date: 1994-07-27
Publication date: 1998-03-12
Anticipated expiration: 2014-07-27
Also published as: MA23296A1; CA2168769C; ZA945772B; CA2168769A1; AU7403494A; WO1995004127A1

Description

WO 95/04127 PCT/US94/08662 1 A PROCESS OF CLEANING CARPETS USING ACTIVE OXYGEN COMPOUNDS IN AN ACIDIC AQUEOUS MEDIUM Technical Field The present invention relates to the use of aqueous compositions for carpet cleaning.

Background of the Invention Carpets produced from synthetic or natural fibres and mixtures thereof are commonly used in residential and commercial applications as a floor covering. Various types of fibres can be used in making carpets such as polyamide and wool.

However, carpets irrespective of whether they are made from natural or synthetic fibres are all prone to soiling and staining when contacted with many household items.

Beverages in particular such as coffee, tea and soft drinks especially those containing acidic dyes can cause unsightly, often dark stains on carpets. In additicn fibres may become WO 95/04127 PCT/US94/08662 2 soiled as a result of dirt particles, grease, oils, foods, pet stains and other solid materials which may be inorganic or organic coming into contact with and adhering to the fibres of the carpet.

Stains or soils are often not readily removed from the carpets, especially if not treated immediately after the spillage has occurred. Indeed, if the stain or soil has become dry the difficulty of removing the stain or soil effectively is significantly increased. As a result of soiling and staining the carpets become unsightly, often malodorous and unhygienic.

Carpets may often also be inhabited by microinsects such as house lice and mites. The presence of microinsects is considered unhygienic and thus it is desirable that such insects can be exterminated and removed from the carpet.

There are a number of carpet cleaning compositions described in the art for removing stains and soils. For example volatile solvent dry cleaning fluids. However, these compositions are not effective on water-soluble stains or Ssoils. Aqueous compositions comprising synthetic detergents have also been described, but are also not satisfactory, especially on colour stains such as coffee, fruit juices and beverages.

L Other aqueous compositions which have been disclosed in the art are compositions comprising hydrogen peroxide having an alkaline pH. However, these compositions are not stable.

The pH must be adjusted just prior to use. This is inconvenient both to the manufacturer, who must supply the ingredients separately and the consumer, who must regulate the pH of the composition before applying it to the area to be treated.

WO 95/04127 PCTIUS94/08662 3 The present invention is the use of a stable aqueous composition comprising hydrogen peroxide or sources thereof having an acidic pH for the cleaning of carpets.

An advantage of the present invention is that the composition is stable and does not require pH adjustment prior to use and can be stored for long periods of time prior to use.

A further advantage of the present invention is that it is applicable to all carpet types, especially delicate natural fibres and is also safe to all carpet dye types, particularly sensitive natural dyes used therein.

Another advantage of the present invention is that it may be applied directly on the carpet without causing damage to the carpet. In addition the cleaning action of the invention commences as soon as the carpet cleaner has been applied to the surface. The use of the carpet cleaner of the present invention does not necessarily require rubbing or rinsing or washing of the carpet.

Aqueous acidic hydrogen peroxide compositions are known in the art. However their use as carpet cleaner has not been previously disclosed.

EP 346 835 discloses an aqueous carpet cleaning composition for synthetic carpets comprising hydrogen peroxide, a water soluble alcohol at pH 7-12 and a method for removing soils from carpets using said composition.

US 3 607 760 discloses an aqueous carpet cleaning composition and the use thereof which comprises hydrocarbon ethers of ethylene glycol, hydrogen peroxide and EDTA. There is no disclosure of pH values.

Melliand TextUber. Int. 57(6), 473-5 discloses the oxidation of wool carpets with aqueous hydrogen peroxide to ~PB~PPY-V Y-~Y ~II~- WO 95/04127 PCT/US94/08662 4 reduce electrostatic charge build-up. The compositions further comprise tetra sodiumdiphosphate hydrate and are at pH 9.

Tenside, Surfactants, Detrg., 23(2), 80-4 discloses an aqueous carpet cleaning and bleaching composition for synthetic and natural fibre carpets comprising hydrogen peroxide and acetic acid or magnesium perphthalate. The article discloses the results of a test to determine the pH dependency of the bleaching effect. From this test it was concluded t'.at the optimum pH value is from 9 to

I

-4a- Summary of the invention The present invention is the use of a stable aqueous composition comprising a source of active oxygen having a pH of from 1 to 6 for the cleaning of carpets.

In its broadest aspect, the present invention provides a method of cleaning carpets which comprises the steps of applying the area to be treated with a stable aqueous composition having a pH of from 1 to 6, and comprising a source of active oxygen, and allowing said composition to dry.

All amounts, percentages and ratios are iiven by weight of the total composition unless otherwise stated.

Throughout the description and claims of this specification, the word "comprise" and variations of the word, such as "comprising" and "comprises", is not intended to exclude other additives or components or integers or steps.

*oem *•ee *e *e 0 e DINWOD'SIMONEWORX\74O4C4DOC

-I

"C

WO 95/04127 PCT/US94/08662 Su.nmmary of t--h4 Invcnti e.

-he present invention is the use o stable aqueous comp.i.tion comprising a sourc a--ctive oxygen having a pH of from 1 to 6 for t eaning of carpets.

amounts, percentages and ratios are given by weight -f the ition unless othrwi-a tatcd.'-- Detailed Description of the Invention The present invention is the use of a stable acidic aqueous composition comprising a source of active oxygen.

The term stable as used herein refers to compositions which will not undergo any chemical or physical interactions, thus the compositions will remain constant and active even when stored for long periods of time. As a result the ingredients of the compositions according to the present invention do not require mixing just prior to said compositions' use or pH regulating. Thus, the amount of available oxygen in the composition during the products lifetime, which is typically 12 months, cannot be less than of the amount of available oxygen present when the composition is formulated.

Thus according to the present invention an essential ingredient is a source of active oxygen. A preferred source according to the present invention is hydrogen peroxide or sources thereof. As used herein a hydrogen peroxide source refers to any compound which produces hydrogen peroxide when said compound is in contact with water. Suitable watersoluble sources of hydrogen peroxide for use herein include percarbonates, metal peroxides and perborates.

In addition other classes of peroxides can be used as an alternative to hydrogen peroxide and sources thereof or INin combination with hydrogen peroxide and sources thereof.

therein L qP -C C- WO 95/04127 PCT/US94/08662 6 Suitable classes include dialkylperoxides, diacylperoxide preformed percarboxylic acids, persulphates and organic and inorganic peroxides.

Hydrogen peroxide or sources thereof provide from 0.1% to 15%, preferably from 0.5% to 10%, most preferably from 1% to 5% by weight of the total composition of active oxygen in said composition.

As used herein active oxygen concentration refers to the percentage concentration of elemental oxygen, with an oxidation number zero, that being reduced to water would be stoichiometrically equivalent to a given percentage concentration of a given peroxide compound, when the peroxide functionality of the peroxide compound is completely reduced to oxides. The active oxygen sources according to the present invention increase the ability of the compositions to remove coloured stains, to destroy malodourous molecules and to kill germs.

The concentration of available oxygen can be determined by methods known in the art, such as the iodimetric method, the permanganometric method and the cerimetric method. Said methods and the criteria for the choice of the appropriate method are described for example in "Hydrogen Peroxide", W.

C. Schumb, C. N. Satterfield and R. L. Wentworth, Reinhold Publishing Corporation, New York, 1955 and "Organic Peroxides", Daniel Swern, Editor Wiley Int. Science, 1970.

Suitable organic and inorganic peroxides for use in the compositions according to the present invention include diacyl and dialkyl peroxides such as dibenzoyl peroxide, dilauroyl peroxide, dicumyl peroxide, persulphuric acid and mixtures thereof. The compositions according to the present invention comprise from 0% to 15%, preferably from 0.005% to of said organic peroxides.

P-C ~III WO 95/04127 PCT/US94/08662 7 Suitable preformed peroxyacids for use in the compositions according to the present invention include diperoxydodecandioic acid DPDA, magnesium perphthalatic acid, perlauric acid, perbenzoic acid, diperoxyazelaic acid and mixtures thereof. The compositions according to the present invention comprise from 0% to 15%, preferably from 0.005% to 10% of said preformed peroxyacids.

Optionally, the compositions may additionally comprise from 0% to 30%, preferably from 2% to 20% of peracid precursors, i.e. compounds that upon reaction with hydrogen peroxide produce peroxyacids. Examples of peracid precursors suitable for use in the present invention can be found among the classes of anhydrides, amides, imides and esters such as acetyl triethyl citrate (ATC) described for instance in EP 91 87 0207, tetra acetyl ethylene diamine (TAED), succinic or maleic anhydrides. Preferably said peracid precursors can be used in an emulsion form as described in unpublished European Patent Application No.: 92870188.7.

The pH of the carpet cleaners as used according to the present invention is from 1 to 6. Therefore, a second essential component of the compositions according to the present invention is an acid. The acid is used to ensure that the pH of the composition is from pH 1 to 6, preferably between pH 2 and 6, more preferably between pH 2 and 5, most preferably between pH 3 and 4.5. In addition some acids can have the advantage that they can form small concentrations of the corresponding peracids by reaction with hydrogen peroxide in-situ, thus enhancing the overall performance of the composition. These acids can be further selected so as to have chelating and/or building properties. The acids of the present invention that may be used for these purposes can be organic or inorganic acids, preferably organic acids such as citric, maleic, oxalic succinic, and tartaric acids.

I ul ~I~IYIR rr~ls~n~- raunr~ WO 95/04127 PCT/US94/08662 According to the present invention the compositions may comprise a number of additional compounds such as surfactants, solvents, chelants and perfumes. The optional ingredients are selected so that they are compatible with hydrogen peroxide and sources thereof.

Surfactants suitable for use herein are well known in the art and include anionic, nonionic, zwitterionic and cationic surfactants and mixtures thereof. The surfactants suitable for use herein are compatible with hydrogen peroxide and sources thereof.

The anionic surfactants which may be used in the present invention include for example alkali metal salts of alkyl substituted benzene sulphonates, alkali metal alkyl sulphonates, alkali metal alkyl sulphates and alkali metal alkyl ether sulphates derived from for example fatty alcohols and alkyl phenols, alkali metal alkane sulphonates, alkali metal olefin sulphonates and alkali metal sulphosuccinates and alkyl succinates, whereby the sodium salts are preferred, alkyl carboxylates and alkyl ether carboxylates.

The nonionic surfactants which may be used include any liquid or solid ethoxylated C 6

-C

24 fatty alcohol nonionic surfactant, alkyl propoxylates and mixtures thereof, fatty acid C 6

-C

24 alkanolamides, C 6

-C

20 polyethylglycol ethers, polyethylene glycol with molecular weight 1000 to 80000 and

C

6

-C

24 amine oxides, glucose amides, alkyl pyrrolidones, betaines.

Suitable cationic surfactants for use herein include quaternary ammonium compounds of the formula R 1

R

2

R

3

R

4

N+

where R 1

,R

2 and R 3 are methyl groups, and R 4 is a C12-15 alkyl group, or where R 1 is an ethyl or hydroxy ethyl group,

R

2 and R 3 are methyl groups and R 4 is a C 12 -1 5 alkyl group.

WO 95/04127 PCT/US94/08662 9 Another optional ingredient are zwitterionic surfactants. Suitable zwitterionic surfactants include derivatives of aliphatic quaternary ammonium, phosphonium, and sulphonium compounds in which the aliphatic moiety can be straight or branched chain and wherein one of the aliphatic substituents contains from about 8 to about 24 carbon atoms and another substituent contains, at least, an anionic water-solubilizing group. Particularly preferred zwitterionic materials are the ethoxylated ammonium sulphonates and sulfates disclosed in U.S. Patents 3,925,262, Laughlin et al., issued December 9, 1975 and 3,929,678, Laughlin et al., issued December 30, 1975. The compositions according to the present invention contain from 0% to 20% of zwitterionic surfactants.

The composition according to the present invention comprise from 0.5% to 70%, preferably from 3% to 50% of said surfactants.

The compositions according to the present invention may further comprise a builder system. Any conventional builder system is suitable for use herein including polycarboxylates and fatty acids, materials such as ethylenediamine tetraacetate, metal ion sequestrants such as aminopolyphosphonates, particularly ethylenediamine tetramethylene phosphonic acid and diethylene triamine pentamethylenephosphonic acid. Though less preferred for obvious environmental reasons, phosphate builders can also be used herein.

Suitable polycarboxylates builders for use herein include citric acid, preferably in the form of a watersoluble salt, derivatives of succinic acid of the formula

R_CH(COOH)CH

2 (COOH) wherein R is C 10 20 alkyl or alkenyl, preferably C 12 16 or wherein R can be substituted with hydroxyl, sulpho sulphoxyl or sulphone substituents.

WO 95/04127 PCT/US94/08662 Specific examples include lauryl succinate, myristyl succinate, palmityl succinate, 2-dodecenylsuccinate, 2tetradecenyl succinate. Succinate builders are preferably used in the form of their water-soluble salts, including sodium, potassium, ammonium and alkanolammonium salts.

Other suitable polycarboxylates are oxodisuccinates and mixtures c-f tartrate monosuccinic and tartrate disuccinic acid such as described in US 4,663,071.

Suitable fatty acid builders for use herein are saturated or unsaturated C 10 -1 8 fatty acids, as well as the corresponding soaps. Preferred saturated species have from 12 to 16 carbon atoms in the alkyl chain. The preferred unsaturated fatty acid is oleic acid.

A preferred builder system for use herein consists of a mixture of citric acid, fatty acids and succinic acid derivatives described herein above. The builder system according to the present invention preferably represents from 0% to 10%, preferably from 1% to 7% by weight of the total composition.

Another optional ingredient is a chelant system. The chelant system may improve the stability of the hydrogen peroxide in the formulation and improve the ability of the compositions to remove metal pigments from the stains and soils. Suitable chelants may be chosen from EDTA, NTA or preferably from biodegradable chelants such as s,s-ethylene diamino disuccinate and dipicolinic acid.

The compositions according to the present invention may also comprise perfumes, solvents, dyes, sud suppressing agents, enzymes, photobleaching and other minors. Solvents suitable for use herein may be selected from octyl alcohol, isopropyl alcohol, propyl alcohol and furfuryl alcohol. Dyes and perfumes are selected from those which are compatible p WO 95/04127 PCT[US94108662 11 with sources of active oxygen. In particular dyes are used at low concentrations to prevent staining. The compositions according to the present invention may additionally comprise soil release polymers to delay soil build up and facilitate cleaning, antistatic agents to reduce static build up and sunscreening agents to protect the carpet or upholstery treated from ultr-violet radiation.

According to the present invention the method of using the cleaning compositions comprises the step of applying the area to be treated with the aqueous composition and allowing the composition to dry.

The composition may be applied directly onto the area to be treated or applied using a cloth or piece of material: In a preferred embodiment of the invention the composition is applied to the area to be treated by using a spraying device. Such a device may be trigger operated or pump operated. The latter is a particularly preferable embodiment if a large area is to be treated as it facilitates the ease of use for the consumer. The spray devices ensure uniform coverage of the area to be treated and maximizes the advantage of the using liquid compositions containing peroxides. This is because the application of product by spray best allows the product to be left to dry on the area treated, without rubbing or washing. This optimises the action time of the composition and allows the best exploitation of the bleaching action of peroxides.

The area to be treated using the composition according to the present invention may be any size. In addition a complete section or even a whole carpet may be applied with the composition according to the present invention. For such purposes a spray device with a pump to allow prolonged spr ying is particularly useful.

WO 95/04127 PCT/US94/08662 12 The amount of the composition applied will depend on the severity of the stain or soil. In the case of stubborn stains more than one application may be required to ensure complete removal of the stain. The carpet cleaning compositions may also be used in order to deodourise the carpet and remove the dinginess of the carpet resulting from a diffused layer of soil which results from general wear.

According to the present invention the compositions may be used for manual carpet cleaning and commercial carpet cleaning machines. For carpet cleaning machines the compositions according to the present invention can be diluted according to the machine operating instructions.

Furthermore, compositions to be used in such machines should be formulated to prevent high sudsing. Preferably the ratio of nonionic surfactant to other surfactants should be higher. More preferably such compositions comprise suds suppressing agents.

According to the present invention the compositions may be used for the removal of odours, stains and soils from carpets or upholstery. In addition the composition may be used o hygenise or disinfect carpets and exterminate microinsects from the carpet or upholstery.

WO 95/04127 PCT/US94/08662 13 Examples The following compositions are made by combining the following ingredients in the listed proportions.

EXAMPLE 1 Hydrogen peroxide Sodium Dodecyl sulphate Poly ethoxy propoxy alcohol

(C

13

-C

15 E04, P02) BHT (di t-butyl hydroxy toluene Perfume, dyes Sulphuric acid Water 0.08 0.2 up to pH 4 Balance EXAMPLE 2 Hydrogen peroxide Ethoxylated alcohol (DobanolR 91-10) Ethoxylated alcohol (DobanolR 23-3) Citric acid NaOH Perfume, dyes Water up to pH 4 0.2 Balance EXAMPLE 3 Hydrogen peroxide Ethoxylated alcohol (DobanolR 91-10) Ethoxylated alcohol (DobanolR 23-2) Acetyl triethyl citrate WO 95/04127 PCT/US94/08662 14 Citric acid up to pH 4 Perfume, dyes 0.2 Water Balance Examples 1 and 2 are preferably to be used for compositions for manual cleaning.

Example 3 is preferably to be used for compositions for carpet cleaning machines.

Example 3 is prepared by mixing together in two separate premixes all the water soluble ingredients on one side, and all the water insoluble ingredients on the other side, such that; Premix 1 Water, H 2 0 2 Dob. 91-10, citric acid, dye.

Premix 2 Dob. 23-2, Acetyl triethyl citrate, perfume.

Premix 1 is poured into premix 2 (or viceversa) and vigorously stirred until a stable emulsion is obtained, typically for 30 minutes to 1 hour.

I. r Irr

Claims

1. A method of cleaning carpets which comprises the step of applying the area to be treated with a stable aqueous composition having a pH of from 1 to 6, and comprising a source of active oxygen, and allowing said composition to dry.

2. A method according to claim 1 wherein said stable aqueous composition has a pH of from 2 to

3. A method according to anyof the preceding claims wherein in said stable aqueous comrnposition the sources of active oxygen are hydrogen peroxide and sources thereof.

4. A method according to any4,of the preceding claims wherein said stable aqueous composition comprises from 0.1% to 15% by weight of said active oxygen. A method according to anY of the preceding claims wherein in said stable aqueous composition the source of active oxygen is a mixture of peracid 15 precursors and hydrogen peroxide.

6. A method according to any of the preceding claims wherein said stable aqueous composition further comprises a surfactant or mixtures thereof.

7. A method according to anyofthe preceding claims wherein said stable aqueous composition further comprises a chelant. 20 8. A method according to any,of the preceding claims wherein said stable aqueous composition further comprises a solvent.

9. A method according to anW the preceding claims wherein said stable aqueous composition used is applied onto the area to be treated by using a carpet cleaning machine. S 25 10. A method according tgany of the preceding claims wherein said stable aqueous composition used is applied onto the area to be treated by using a spray device.

11. A method according to claim 10 wherein said spray device is pump operated.

16- 12. A method according to claim 1 wherein the stable aqueous composition is substantially as herein described with reference to any one of the examples. DATED: 15 December, 1997 PHILLIPS ORMONDE FITZPATRICK Attorneys for: THE PROCTER GAMBLE COMPANY *e* e e e eo S CWINWORD\SIMONEWORXl'7434C94 DOC INTERNATIONAL SEARCH REPORT International application No. PCT/US594/08662 A. CLASSIFICATION OF SUBJECT MATT'ER IPC(6) :CUD 7/08, 7/38,7/54; DO6L 1/12, 3/02 US CL :8/111, 139; 252/95, 100 According to International Patent Classification (IPC) or to both national classification and IPC B. FIELDS SEARCHED Minimium documentation searched (classification system followed by classification symbols) U.S. /ill, 139; 252/95, 100 Documentation searched other than minimum documentation to the extent that such documents are included in the fields searched Electronic data base consulted during the international search (name of data base and, where practicable, search terms used) C. DOCUMENTS CONSIDERED TO BE RELEVANT Category* Citation of document, with indication, where appropriate, of the relevant passages Relevant to claim No. X Tenside, surfactants, detergents, Vol. 23, No. 2, March/April 1-3 1986, H. Krussman et al., "Zum Einsatz der Bleiche bei der Teppichreinigung", pages 80-84, especially Bild 2 on page

81. E US, A, 5,338,475 [COREY] 16 August 1994 See TABLE 1, 1-3 EXAMPLE 6 and the claims. Further documents are listed in the continuation of Box C. See patent family annex. Special categories of cited dcum:. .r Wert dcmen puished after thinterntina fin date or prioity dale and Dot in conflict with the application but cited to undcrotand the documnt deflain the general tate of the an which ia Dtcosiderad principle or theory underlying the invention to be of particular relevance E' arler octntet pblihedon r fte th snemntioal ilig X. document of particular relevance; the claimed invention cannot be arler oc= 1 pb~ibodon r aler he ntenatona rdng ateconsidered novel or cannot be' onsidered to involve an inventive step W doecument which may throw doubts 08 priority clam(s) or which is when the docuinent is taken io scid reazso e pcaiofdi eoeaohed)an o docmentm of particular relevance; the claimed invention cantnot be specu masn (a.~ectled)conakierod to involve an inventive step when the document is documnt referring to an oral disclosure. use. exhmibition or other combined with one or more other such doctuments, such combination 'means being obvious to a person akilled in the art PF documnent published prior to the isatrational filing daze but W"ei than document nmmber of' the same patent family the priority date claimed Date of the actual completion of the international search Date of mailing of the international search report 22 OCTOBER 1994 15 NOV 1994 Name and mailing address of the ISA/US Authorized Commnissioner of Patent and Trademarks Box PCT DENNIS L. ALBRECH Washington, D.C. 20231 w' Facsimile No. (703) 305-3230 Telephone No. (703) 308.,2525 Form PCT/ISA/210 (second shct)(July 1992)* I V ~~~rr~an~l~~nra~ 8B INTERNATIONAL SEARCH REPORT International application No. PCT/US94/08662 Box I Observations where certain claims were found unsearchable (Continuation of item 1 of first sheet) This international report has not been established in respect of certain claims under Article 17(2Xa) for the following reasons: I. Claims Nos.: because they relate to subject matter not required to be searched by this Authority, namely: Claims Nos.: because they relate to parts of the international application that do not comply with the prescribed requirements to such an extent that no meaningful international search can be carried out, specifically: 3. Claims Nos.: 4-11 because they are dependent claims and are not drafted in accordance with the second and third sentences of Rule 6.4(a). Bo= II Observations where unity of invention is lacking (Continuation of item 2 of first sheet) This International Searching Authority found multiple inventions in this international application, as follows: 1. As all required additional search fees were timely paid by the applicant, this international search report covers all searchable claims. 2. As all searchable claims could be searched without effort justifying an additional fee, this Authority did not invite payment of any additional fee. 3. As only some of the required additional search fees were timely paid by the applicant, this international search report covers only those claims for which fees were paid, specifically claims Nos.: 4. [O No required additional search fees were timely paid by the applicant. Consequently, this international search report is restricted to the invention first mentioned in the claims; it is covered by claims Nos.: Remark on Protest The additional search fees were accompanied by the applicant's protest. [O No protest accompanied the payment of additional search fees. Form PCT/ISA/210 (continuation of first sheet(l))(July 1992)* -I 1 i 0