EP0997525A1

EP0997525A1 - Process of cleaning carpets with a composition comprising a poly (vinyl methyl ether/maleic acid) copolymer

Info

Publication number: EP0997525A1
Application number: EP99870042A
Authority: EP
Inventors: Italo Corzani (NMN); Fabio Lumino (NMN); Pierre Antoine Dresco; Stefano Scialla (Nmn)
Original assignee: Procter and Gamble Co
Current assignee: Procter and Gamble Co
Priority date: 1998-10-30
Filing date: 1999-03-11
Publication date: 2000-05-03
Also published as: CA2347745A1; JP2002528662A; AU6281799A; WO2000026330A1

Abstract

The present invention relates to a process of cleaning a carpet with a liquid composition comprising a poly (vinyl methyl ether / maleic acid) copolymer. The carpet cleaning composition according to the present invention provides carpet cleaning and/or carpet anti-resoiling benefits.

Description

Technical Field

The present invention relates to a process of cleaning carpets using a liquid composition. More particularly, the present invention relates to a process of cleaning carpets whereby carpet cleaning and/or carpet anti-resoiling benefits are provided.

Background of the Invention

Carpets produced from synthetic or natural fibers and mixtures thereof are commonly used in residential and commercial applications as a floor covering. Various types of fibers can be used in making carpets such as polyamide fibers, polyester fibers as well as wool, cotton or even silk in the case of rugs.
However, carpets irrespective of whether they are made from natural or synthetic fibers are all prone to soiling and staining when contacted with many household items. Food, grease, oils, beverages in particular such as coffee, tea and soft drinks especially those containing acidic dyes can cause unsightly, often dark stains on carpets. Also fibers may become soiled as a result of dirt particles, clay, dust, i.e., particulate soils in general, coming into contact with and adhering to the fibers of the carpet. These latter soils often appear in the form of a diffuse layer of soils rather than in the form of spots and tend to accumulate particularly in the so called "high traffic areas" such as near doors as a result of intensive use of the carpets in such areas.
Compositions for cleaning carpets are already known in the art. For example as disclosed in EP-A-751 213.
However, it is understood that consumers have a need for a carpet cleaning product delivering anti-resoiling benefits to the carpets treated therewith. Indeed, consumers are looking for liquid carpet cleaning compositions that would render a carpet first treated therewith, less prone to soiling and thus facilitate the next-time cleaning operation.
Thus, the objective of the present invention is to provide a process for cleaning a carpet with a liquid carpet cleaning composition that will impart anti-resoiling properties to a carpet treated therewith.
Furthermore, it is an objective of the present invention to provide a process of cleaning a carpet which provides excellent overall cleaning performance on various types of stains including particulate stains, greasy stains, bleachable stains and/or enzymatic stains.
It has now been found that the above objectives can be met by a process of cleaning a carpet with a liquid composition comprising a poly (vinyl methyl ether / maleic acid) copolymer as an anti-resoiling agent.
An advantage of the process of cleaning carpets according to the present invention is that said process provides an easy and fast way for a user to clean a carpet, while providing excellent overall cleaning performance. More advantageously, the process of cleaning carpets according to the present invention provides excellent cleaning performance, when both used to clean the whole carpet or localized carpet stains. In addition to this, this process does not result in tacky residues being left on carpets after treatment. The presence of tacky residues has been found to increase re-soiling since soils can stick to the residues.
Advantageously, excellent cleaning performance is obtained on different types of stains and soils, including enzymatic stains as well as particulate stains and/or greasy stains, especially in highly soiled, so called "high traffic areas".
A further advantage of the present invention is that the process of cleaning carpets herein is applicable to all carpet types, especially delicate natural fibers. The present invention is also suitable to be used to clean hard wearing textiles and fabrics, e.g., upholstery, rugs, curtains.
Yet another advantage of the process of cleaning carpets and of the compositions of the present invention is that they may be applied directly on the carpet without causing damage to the carpet. In particular, the compositions used in the present process are safe to all known carpet dyes, even well known particularly sensitive natural dyes.

Background art

The following documents are representative of the prior art available on carpet cleaning compositions.
EP-A-751 213 discloses a carpet cleaning composition comprising salicylic acid and a compound selected from the group consisting of amine oxides, soil suspending polycarboxylate or polyamine polymers, hydroxy-pyridine N-oxides, chelating agents and mixtures thereof. However, poly (vinyl methyl ether / maleic acid) copolymers are not disclosed therein.

Summary of the Invention

The present invention encompasses a process of cleaning a carpet with a liquid composition comprising a poly (vinyl methyl ether / maleic acid) copolymer.
In a preferred embodiment said composition further comprises a peroxygen bleach.
In another preferred embodiment said composition comprises a further anti-resoiling agent, preferably a polyamine polymer, more preferably an alkoxylated polyamine polymer.
In still another preferred embodiment said composition further comprises a surfactant, preferably an anionic surfactant, a zwitterionic surfactant or a mixture thereof, most preferably a sarcosinate surfactant.
The present invention also encompasses the use of a poly (vinyl methyl ether / maleic acid) copolymer as an anti-resoiling agent in a carpet cleaning composition to clean carpets whereby said carpet cleaning composition provides carpet cleaning and/or carpet anti-resoiling benefits.

Detailed Description of the Invention

Process of cleaning a carpet

The present invention encompasses a process of cleaning a carpet with a liquid composition comprising a poly (vinyl methyl ether / maleic acid) copolymer.
Preferably, said process comprises the steps of applying said composition to the surface of the carpet and leaving said composition to substantially dry onto the carpet. More preferably said process of cleaning a carpet further comprises the step of removing said composition, even more preferably said process of cleaning a carpet further comprises the step of removing said composition in combination with soil particles.
In a preferred embodiment of the present invention a liquid composition according to the present invention is applied onto the carpet by using a dispensing device, preferably a spray dispenser. Said spray dispenser is a container that has at least one aperture through which the composition is dispensed to produce a spray of droplets.
Such a spray dispenser may comprise a means for delivering the composition by a pump ("pump spray dispenser") or may be operated by any source of pressurised gas such as an aerosol-can or a pressurizer. Pump spray dispensers may be manually operated or electrically operated. Said spray dispensers are particularly preferable if a large area is to be treated as they facilitate the ease of use by the consumer. Said spray dispensers ensure uniform coverage of the area to be treated. Furthermore, said spray dispensers optimise the action time of the composition as the application of product by spraying best allows the product to be left to substantially dry on the area treated in an acceptable amount of time, preferably even without rubbing or brushing.
Preferred spray dispensers herein are manually or electrically operated pump spray dispensers. Typical manually operated pump spray dispensers include push button operated or trigger operated pump spray dispenser. A preferred spray dispenser herein is a container wherein the means for delivering the composition comprises an electrically driven pump and a spray arm. Said spray arm is either extended or extendible and has at least one aperture so that in operation, the composition is pumped by said electrically driven pump from the container, through the spray arm to the aperture from which it is dispensed. It is preferred that the spray arm communicates with the container by means of a flexible connector. The spray arm may have at least one aperture located along its length. The spray arm makes it easier to control where the composition is sprayed and therefore, the accuracy with which the composition is applied is increased. The electrically driven pump may be, for example, a gear pump, an impeller pump, a piston pump, a screw pump, a peristaltic pump, a diaphragm pump, or any other miniature pump. In a highly preferred embodiment of the electrically driven pump for use herein the pump is a gear pump with a typical speed between 6000 rpm and 12000 rpm. The electrically driven pump is driven by a means such as an electric motor which typically produces a torque between 1 and 20 mN.m. The electric motor must in turn be provided with a power source. The power source may be either main electricity (optionally via transformer), or it may be a throw-away battery or rechargeable battery. The spray arm may be rigidly extended. However such a spray arm can be difficult to store, and the spray arm is preferably extensible either by means of telescopic or foldable configuration.
In a highly preferred embodiment, the composition is applied onto the carpet in the form of a spray of droplets having a particle size distribution with a mean diameter D(v,0.9) of less than 1500 microns, preferably less than 1000 microns, more preferably of less than 750 microns, even more preferably less than 500 microns, and most preferably from 350 microns to 10 microns.
By "mean diameter D(v,0.9) of less than 1500 microns" for a droplet size distribution it is meant that 90% of the spray of droplets dispensed (expressed in volume unit) has a droplet diameter of less than 1500 microns. For instance, a D(v,0.9) of less than 1500 microns indicates that 90% of the total sprayed volume is dispensed with droplets whose diameter is less than 1500 microns.
The particle size distribution of a spray of droplets can be determined by following the procedure detailed herebelow:
A suitable test equipment is the Malvern Mastersizer S LongBed® with 1000 mm lens and a maximum particle size range of 3475 microns. The Malvern Mastersizer S LongBed® provides a 21 cm opening (between its lenses) to accommodate spray flow. In all readings at the Malvern®, the lens surface must remain free of spray contamination. In the present setup procedure, the distance from the aperture of the spray dispenser to the laser was fixed at 8 cm, this to minimize lens contamination. At 8 cm distance, the spray was directed to the laser beam to place the laser center to the spray cone. At least three readings have to be made for each composition sprayed to determine the particle size distribution of the spray of droplets. The spray dispenser to be used in the test according to the present invention is an electrically operated spray dispenser, preferably a battery-operated system. If a battery-operated system is used, a "Full charge test" is being performed. By "Full charge test" it is meant herein, that the current was held consistent by connecting the battery-operated spray dispenser to a 3.9 voltage direct current (vdc) from an external power supply, this ensures a constant spray force. A comparative spray dispenser used herein is a hand-held trigger-operated spray dispenser. Hand-held trigger-operated systems have to be tested repeatability with three different persons. These persons are chosen for their varied ability to actuate the trigger against force: Small female, female with strong finger strength, and medium male.
Any container adapted to deliver a spray of droplets as defined herein is suitable for use herein. Several modifications can be made to the conventional, single aperture, spray head to ensure that a spray of such droplets as required herein is formed.
The amount of the compositions for the cleaning of carpets according to the present invention 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 area to be cleaned by applying the compositions according to the present invention may be of any size. Indeed, a complete section or more preferably the whole carpet may be treated with the composition for the cleaning of carpets according to the present invention.
In a process of cleaning a carpet according to a preferred embodiment of the present invention the step of applying a composition onto the carpets as described herein before, does not need to be followed by a step where manual action is required other than the final optional removing step. Indeed the compositions herein allow excellent cleaning performance without requiring any manual action like rubbing and/or brushing. An advantage of the present invention is that the cleaning action of the present composition commences as soon as said compositions are applied onto said carpet.
In a preferred embodiment, the composition applied to the carpet is left to substantially dry. Typically, the composition is left to dry on the carpet for less than 2 hour, preferably less than 1 hour, more preferably less than 40 minutes, even more preferably from 1 to 30 minutes and most preferably from 1 to 20 minutes.
By "substantially dry" it is meant herein the stage where at least 40%, preferably at least 60% of the initial amount of composition dispensed onto the carpet is lost due to evaporation.
Indeed, said composition may be left to substantially dry until said composition combined with dirt forms substantially dry residues. Preferably, said composition more preferably said substantially dry residues, are then removed from the carpet. Even more preferably said substantially dry residues are removed mechanically, most preferably by vacuum cleaning. This may be carried out with the help of any commercially available vacuum cleaners like for instance a standard Hoover® 1300W vacuuming machine.
According to the present invention the compositions herein may be used for the removal of stains and soils as well as of odors from carpets or hard wearing textiles and fabrics, e.g., upholstery. In addition the compositions according to the present invention may be used to hygienise, disinfect and/or exterminate microinsects from carpets or hard wearing textiles and fabrics, e.g., upholstery, rugs, curtains.

The composition

The compositions of the present invention are formulated as liquid compositions. Preferred compositions herein are aqueous compositions and therefore, preferably comprise water more preferably in an amount of from 60% to 98%, even more preferably of from 80% to 97% and most preferably 85% to 97% by weight of the total composition.
The pH of the liquid compositions according to the present invention may typically be from 1 to 14. In a preferred embodiment, the recommended pH range is from 1 to 10, preferably from pH 2 to 8, more preferably from pH 3 to 7, even more preferably from pH 4.5 to 7 and most preferably from 3.5 to 6.5. Indeed, it has been surprisingly found that cleaning performance is further improved at these preferred pH ranges. Also these preferred pH ranges contribute to the stability of hydrogen peroxide, when present. Accordingly, the compositions herein may further comprise an acid or base to adjust pH as appropriate.
Preferred acids herein are organic or inorganic acids or mixtures thereof. Preferred organic acids are acetic acid, or citric acid or a mixture thereof. Preferred inorganic acids are sulfuric acid or phosphoric acid or a mixture thereof. A particularly preferred acid to be used herein is an inorganic acid and most preferred is sulfuric acid.
Typical levels of such acids, when present, are of from 0.01% to 1.0%, preferably from 0.05% to 0.8% and more preferably from 0.1% to 0.5% by weight of the total composition.
The bases to be used herein can be organic or inorganic bases. Suitable bases for use herein are the caustic alkalis, such as sodium hydroxide, potassium hydroxide and/or lithium hydroxide, and/or the alkali metal oxides such, as sodium and/or potassium oxide or mixtures thereof. A preferred base is a caustic alkali, more preferably sodium hydroxide and/or potassium hydroxide.
Other suitable bases include ammonia, ammonium carbonate and hydrogen carbonate.
Typical levels of such bases, when present, are of from 0.01% to 1.0%, preferably from 0.05% to 0.8% and more preferably from 0.1% to 0.5% by weight of the total composition.

Poly (vinyl methyl ether / maleic acid) copolymer

As an essential ingredient the compositions according to the present invention comprise a poly (vinyl methyl ether / maleic acid) copolymer.
The liquid compositions herein may comprise from 0.001% to 10%, preferably from 0.01% to 5%, more preferably from 0.05% to 2% and most preferably 0.1% to 1% by weight of the total composition of poly (vinyl methyl ether / maleic acid) copolymer.
Suitable poly (vinyl methyl ether / maleic acid) copolymers are according to the general formula :
wherein n (degree of polymerisation) is an integer of from 50 to 1600, preferably from 100 to 800, and more preferably from 200 to 400.
Accordingly, suitable poly (vinyl methyl ether / maleic acid) copolymers for use herein have an average molecular weight of from 1'000 to 10'000'000, preferably 10'000 to 1'000'000, more preferably from 10'000 to 500'000, and most preferably from 50'000 to 100'000.
Suitable poly (vinyl methyl ether / maleic acid) copolymers are commercially available, for instance, from ISP Corporation, New York, NY and Montreal, Canada under the product names Gantrez AN Copolymer® (AN-119 copolymer, average molecular weight of 20'000; AN-139 copolymer, average molecular weight of 41'000; AN-149 copolymer, average molecular weight of 50'000; AN-169 copolymer, average molecular weight of 67'000; AN-179 copolymer, average molecular weight of 80'000), Gantrez S® (Gantrez S97®, average molecular weight of 70'000), and Gantrez ES® (ES-225, ES-335, ES-425, ES-435), Gantrez V® (V-215, V-225, V-425).
Preferably the poly (vinyl methyl ether / maleic acid) copolymers are either crosslinked or not crosslinked, i.e., linear. More preferably the poly (vinyl methyl ether / maleic acid) copolymers are not crosslinked.
It has now been found that when poly (vinyl methyl ether / maleic acid) copolymers, as described herein are added into liquid compositions, a film, i.e., a layer of these polymers, is left on the carpet fibers treated with said composition. The film reduces adhesion of soils onto said carpet fibers treated with the composition according to the present invention and/or facilitate removal of soils subsequently deposited thereon. Thus, less effort (e.g., less vacuum cleaning and/or less chemical action) is required to remove the soils in the next cleaning operation ("carpet anti-resoiling performance/ benefit"), as compared to the cleaning of a similarly soiled carpet which has been first treated with the same composition but wherein an anti-resoiling agent is absent.
Furthermore, It has been found that the presence of the poly (vinyl methyl ether / maleic acid) copolymers, in the compositions herein further contributes to the overall cleaning performance ("carpet cleaning benefit") of the compositions herein.
Indeed, it has been observed that the poly (vinyl methyl ether / maleic acid) copolymers are capable of complexing or even encapsulating soil particles on a treated carpet and thereby form solid and glassy residues with said soil particles upon drying of the composition as described herein. More particularly, more than 90%, preferably more than 95% of the residues left onto the carpet are solid and glassy. By 'glassy' it is meant that the residues are non-sticky, i.e., they do not stick to the carpet fibers and/or each other. This results in a process of cleaning carpets whereby the solid and glassy residues left onto the carpets are removed more easily as opposed to residues being sticky, and thus difficult to remove (e.g., by vacuum cleaning said carpets). The presence of the poly (vinyl methyl ether / maleic acid) copolymers reduces or even prevents the formation of tacky residues on the surface of the carpet upon drying, as compared to the same compositions but without the poly (vinyl methyl ether / maleic acid) copolymers.
Additionally, by almost completely removing the residues the present invention reduces or even prevents soil re-deposition on the carpet.
The compositions employed in the process of cleaning carpets according to the present invention provide excellent cleaning performance on various types of soils including diffuse soils (e.g., particulate and/or greasy soils) that tend to accumulate in the so called "high traffic areas" but also in delivering good cleaning performance on other types of stains or soils, i.e., enzymatic stains like blood.
By "high traffic areas" it is meant herein areas with an intensive use of the carpets in such areas as for example near doors.
By "particulate stains" it is meant herein any soils or stains of particulate nature that can be found on any carpet, e.g. clay, dirt, dust, mud, concrete and the like.
By "greasy/oily stains" it is meant herein any soils or stains of greasy/oily nature that can be found on any carpet, e.g., make-up, lipstick, dirty motor oil and mineral oil, greasy food like mayonnaise and spaghetti sauce.
By "enzymatic stains" it is meant herein any soils or stains of enzymatic nature that can be found on any carpet, e.g., grass.
The cleaning performance of a given composition on a soiled carpet may be evaluated by the following test method : A liquid composition according to the present invention is first applied, preferably sprayed, onto the stained portion of a carpet, left to act thereon from 1 to 60 minutes, preferably 30 minutes, after which the carpet is vacuum cleaned using any commercially available vacuum cleaners like for instance a standard Hoover® 1300W vacuuming machine. The soils used in this test may be particulate stains, greasy/oily stains or enzymatic stain as described above. The cleaning performance may be evaluated by visual using panel score units to rate the cleaning performance.
The anti-resoiling performance of a give composition on a soiled carpet may be evaluated by the following test method : A liquid composition according to the present invention is first applied, preferably sprayed, onto the carpet, preferably the stained portion of said carpet, left to act thereon from 1 to 60 minutes, preferably 30 minutes, after which the carpet is vacuum cleaned using any commercially available vacuum cleaners like for instance a standard Hoover® 1300W vacuuming machine. The carpet is left in a 'high traffic area' for a period of time of from 1 hour to several weeks, preferably several days. The anti resoiling performance may be evaluated by visual grading using panel score units to rate the anti resoiling performance.

Optional ingredients

Peroxygen bleach

As an optional but highly preferred ingredient the compositions according to the present invention may comprise a peroxygen bleach.
Suitable peroxygen bleaches to be used herein are selected from the group consisting of: hydrogen peroxide; water soluble sources of hydrogen peroxide; organic or inorganic peracids; hydroperoxides; diacyl peroxides; and mixtures thereof.
As used herein a hydrogen peroxide source refers to any compound that produces perhydroxyl ions when said compound is in contact with water. Suitable water-soluble sources of hydrogen peroxide for use herein are selected from the group consisting of percarbonates, perborates and persilicates and mixtures thereof.
Suitable diacyl peroxides for use herein are selected from the group consisting of aliphatic, aromatic and aliphatic-aromatic diacyl peroxides, and mixtures thereof.
Suitable aliphatic diacyl peroxides for use herein are dilauroyl peroxide, didecanoyl peroxide, dimyristoyl peroxide, or mixtures thereof. A suitable aromatic diacyl peroxide for use herein is for example benzoyl peroxide. A suitable aliphatic-aromatic diacyl peroxide for use herein is for example lauroyl benzoyl peroxide. Such diacyl peroxides have the advantage to be particularly safe to carpets and carpet dyes while delivering excellent bleaching performance.
Suitable organic or inorganic peracids for use herein are selected from the group consisting of : persulphates such as monopersulfate; peroxyacids such as diperoxydodecandioic acid (DPDA); magnesium perphthalic acid; perlauric acid; perbenzoic and alkylperbenzoic acids; and mixtures thereof.
Suitable hydroperoxides for use herein are selected from the group consisting of tert-butyl hydroperoxide, cumyl hydroperoxide, 2,4,4-trimethylpentyl-2-hydroperoxide, di-isopropylbenzene-monohydroperoxide, tert-amyl hydroperoxide and 2,5-dimethyl-hexane-2,5-dihydroperoxide and mixtures thereof. Such hydroperoxides have the advantage to be particularly safe to carpets and carpet dyes while delivering excellent bleaching performance.
Preferred peroxygen bleaches herein are selected from the group consisting of : hydrogen peroxide; water soluble sources of hydrogen peroxide; organic or inorganic peracids; hydroperoxides; and diacyl peroxides; and mixtures thereof. More preferred peroxygen bleaches herein are selected from the group consisting of hydrogen peroxide, water soluble sources of hydrogen peroxide and diacyl peroxides and mixtures thereof. Even more preferred peroxygen bleaches herein are selected from the group consisting of hydrogen peroxide, water soluble sources of hydrogen peroxide, aliphatic diacyl peroxides, aromatic diacyl peroxides and aliphatic-aromatic diacyl peroxides and mixtures thereof. Most preferred peroxygen bleaches herein are hydrogen peroxide, water soluble sources of hydrogen peroxide or mixtures thereof.
Typically, the liquid compositions herein comprise from 0.01% to 20%, preferably from 0.5 % to 10%, and more preferably from 1% to 7% by weight of the total composition of a peroxygen bleach, or mixtures thereof.
The presence of a peroxygen bleach in preferred compositions employed in the process of cleaning carpets according to the present invention contributes to the excellent cleaning and sanitizing performance on various types of soils including on spot stains like bleachable stains (e.g., coffee, beverage, food) of the compositions of the present invention.
By "bleachable stains" it is meant herein any soils or stains containing ingredients sensitive to bleach that can be found on any carpet, e.g., coffee or tea.

Further anti-resoiling agent

The compositions as disclosed herein may comprise as a highly preferred optional ingredient a further anti-resoiling agent on top of the poly (vinyl methyl ether / maleic acid) copolymers.
Suitable further anti-resoiling agents include anti-resoiling polymers.
Suitable anti-resoiling polymers include soil suspending polyamine polymers. Any soil suspending polyamine polymer known to those skilled in the art may also be used herein. Particularly suitable polyamine polymers for use herein are alkoxylated polyamines. Such materials can conveniently be represented as molecules of the empirical structures with repeating units :
and
wherein R is a hydrocarbyl group, usually of 2-6 carbon atoms; R₁ may be a C₁-C₂₀ hydrocarbon; the alkoxy groups are ethoxy, propoxy, and the like, and y is from 2 to 30, most preferably from 7 to 20; n is an integer of at least 2, preferably from 2 to 40, most preferably from 2 to 5; and X- is an anion such as halide or methylsulfate, resulting from the quaternization reaction.
The most highly preferred polyamines for use herein are the so-called ethoxylated polyethylene amines, i.e., the polymerized reaction product of ethylene oxide with ethyleneimine, having the general formula :
wherein y is from 2 to 50, preferably from 5 to 30, and n is from 1 to 40, preferably from 2 to 40. Particularly preferred for use herein is an ethoxylated polyethylene amine, in particular an ethoxylated polyethylene amine wherein n=2 and y=20, and an ethoxylated polyethylene amine wherein n=40 and y=7.
Suitable ethoxylated polyethylene amines are commercially available from Nippon Shokubai CO., LTD under the product names ESP-0620A® (ethoxylated polyethylene amine wherein n=2 and y=20) or from BASF under the product names ES-8165 and from BASF under the product name LUTENSIT K - 187/50® (ethoxylated polyethylene amine wherein n=40 and y=7).
Suitable anti-resoiling polymers also include polyamine N-oxide polymers.
Suitable polyamine N-oxide polymers for use herein are according to the following formula : R-A_x-P; containing at least one N-oxide group (N-O group); wherein :
P is a polymerizable unit to which an N-O group can be attached and/or the N-O group can form part of the polymerizable unit;
A is one of the following structures:
x is 0 or 1;
and R is an aliphatic, ethoxylated aliphatic, aromatic, heterocyclic or alicyclic group or any combination thereof to which the N-O group can be attached to R or the nitrogen of the N-O group is part of R.
By "N-O group" it is meant one of the following general structures:
wherein R₁, R₂, R₃ are aliphatic, aromatic, heterocyclic or alicyclic groups or combinations thereof; x, y and z are 0 or 1; and the nitrogen of the N-O group can be attached or form part of any of the aforementioned groups.
Any polymerizable unit P can be used as long as the amine oxide polymer formed is water-soluble and provides the carpet cleaning composition with carpet cleaning and/or carpet anti-resoiling benefits. Preferred polymerizable unit P are vinyl, alkylenes, esters, ethers, amides, imides, acrylates and mixtures thereof. A more preferred polymerizable unit P is vinyl.
Preferred polyamine N-oxide polymers are those wherein R is a heterocyclic group such as pyridine, pyrrole, imidazole, or a derivative thereof, to which the nitrogen of the N-O group can be attached or the N-O group is part of these groups. Most preferred polyamine N-oxide polymers are those wherein R is a pyridine.
The polyamine N-oxide polymer can be obtained in almost any degree of polymerization. Typically, the average molecular weight is within the range of 1,000 to 100,000; more preferred 5,000 to 100,000; most preferred 5,000 to 25,000.
Suitable polyamine N-oxide polymers are polyvinyl pyridine-N-oxide polymers wherein : the polymerizable unit P is vinyl; x=0; and R is pyridine wherein the nitrogen of the N-O group is part of.
Suitable poly vinyl pyridine-N-oxide polymers are commercially available from Hoechst under the trade name of Hoe S 4268®, and from Reilly Industries Inc. under the trade name of PVNO.
Furthermore, suitable anti-resoiling polymers include N-vinyl polymer.
Suitable N-vinyl polymers include polyvinyl pyrrolidone polymers, co-polymers of N-vinylpyrrolidone and N-vinylimidazole, co-polymers of N-vinylpyrrolidone and acrylic acid, and mixtures thereof.
Suitable co-polymers of N-vinylpyrrolidone and N-vinylimidazole polymers (referred to as a class as "PVPVI") are according to the formula :
in which n is between 50 and 500 and preferably between 80 and 200 and m is between 50 and 500 and preferably between 80 and 200.
Preferably the PVPVI has an average molecular weight range from 1,000 to 100,000, more preferably from 5,000 to 100,000, and most preferably from 5,000 to 20,000. (The average molecular weight range is determined by light scattering as described in Barth, et al., Chemical Analysis, Vol 113. "Modern Methods of Polymer Characterization", the disclosures of which are incorporated herein by reference.)
The PVPVI co-polymers typically have a molar ratio of N-vinylimidazole to N-vinylpyrrolidone from 1:1 to 0.2:1, more preferably from 0.8:1 to 0.3:1, most preferably from 0.6:1 to 0.4:1. These co-polymers can be either linear or branched.
Suitable co-polymers of N-vinylpyrrolidone and N-vinylimidazole are commercially available from BASF, under the trade name of Sokalan® PG55.
Suitable polyvinylpyrrolidones ("PVP") for use herein are homopolymers of N-vinylpyrrolidone having the following repeating monomer:
Preferred vinylpyrrolidone homopolymers for use herein have an average molecular weight of from 1,000 to 100,000, preferably from 5,000 to 100,000, and more preferably from 5,000 to 20,000.
Suitable vinylpyrrolidone homopolymers are commercially available from BASF under the trade names Luviskol® K15 (viscosity molecular weight of 10,000), Luviskol® K25 (viscosity molecular weight of 24,000), Luviskol® K30 (viscosity molecular weight of 40,000), and other vinylpyrrolidone homopolymers known to persons skilled in the detergent field (see for example EP-A-262,897 and EP-A-256,696).
Suitable co-polymers of N-vinylpyrrolidone and acrylic acid (referred to as a class as "PV/AA") are according to the formula :
in which n is between 50 and 1000 and preferably between 100 and 200 and m is between 150 and 3000 and preferably between 300 and 600.
Preferably the PV/AA have an average molecular weight range from 1,000 to 100,000, more preferably from 5,000 to 100,000, and most preferably from 5,000 to 25,000.
Suitable co-polymers of N-vinylpyrrolidone and acrylic acid are commercially available from BASF under the trade name Sokalan® PG 310.
Preferred N-vinyl polymers are polyvinyl pyrrolidone polymers, co-polymers of N-vinylpyrrolidone and N-vinylimidazole, co-polymers of N-vinylpyrrolidone and acrylic acid, and mixtures thereof, even more preferred are polyvinyl pyrrolidone polymers.
Suitable anti-resoiling polymers also include soil suspending polycarboxylate polymers.
Any soil suspending polycarboxylate polymer known to those skilled in the art can be used according to the present invention such as homo- or co-polymeric polycarboxylic acids or their salts including polyacrylates and copolymers of maleic anhydride or/and acrylic acid and the like. Indeed, such soil suspending polycarboxylate polymers can be prepared by polymerizing or copolymerizing suitable unsaturated monomers, preferably in their acid form. Unsaturated monomeric acids that can be polymerized to form suitable polymeric polycarboxylates include acrylic acid, maleic acid (or maleic anhydride), fumaric acid, itaconic acid, aconitic acid, mesaconic acid, citraconic acid and methylenemalonic acid. The presence in the polymeric polycarboxylates herein of monomeric segments, containing no carboxylate radicals such as vinylmethyl ether, styrene, ethylene, etc. is suitable provided that such segments do not constitute more than 40% by weight.
Particularly suitable polymeric polycarboxylates to be used herein can be derived from acrylic acid. Such acrylic acid-based polymers which are useful herein are the water-soluble salts of polymerized acrylic acid. The average molecular weight of such polymers in the acid form preferably ranges from 2,000 to 10,000, more preferably from 4,000 to 7,000 and most preferably from 4,000 to 5,000. Water-soluble salts of such acrylic acid polymers can include, for example, the alkali metal, ammonium and substituted ammonium salts. Soluble polymers of this type are known materials. Use of polyacrylates of this type in detergent compositions has been disclosed, for example, in Diehl, U.S. Patent 3,308,067, issued March 7, 1967.
Acrylic/maleic-based copolymers may also be used as a preferred soil suspending polycarboxylic polymer. Such materials include the water-soluble salts of copolymers of acrylic acid and maleic acid. The average molecular weight of such copolymers in the acid form preferably ranges from 2,000 to 100,000, more preferably from 5,000 to 75,000, most preferably from 7,000 to 65,000. The ratio of acrylate to maleate segments in such copolymers will generally range from 30:1 to 1:1, more preferably from 10:1 to 2:1. Water-soluble salts of such acrylic acid/maleic acid copolymers can include, for example, the alkali metal, ammonium and substituted ammonium salts. Soluble acrylate/maleate copolymers of this type are known materials which are described in European Patent Application No. 66915, published December 15, 1982. Particularly preferred is a copolymer of maleic / acrylic acid with an average molecular weight of 70,000. Such copolymers are commercially available from BASF under the trade name SOKALAN® CP5.
Other suitable anti-resoiling polymers include those anti-resoiling polymers having: (a) one or more nonionic hydrophile components consisting essentially of (i) polyoxyethylene segments with a degree of polymerization of at least 2, or (ii) oxypropylene or polyoxypropylene segments with a degree of polymerization of from 2 to 10, wherein said hydrophile segment does not encompass any oxypropylene unit unless it is bonded to adjacent moieties at each end by ether linkages, or (iii) a mixture of oxyalkylene units comprising oxyethylene and from 1 to about 30 oxypropylene units wherein said mixture contains a sufficient amount of oxyethylene units such that the hydrophile component has hydrophilicity great enough to increase the hydrophilicity of conventional polyester synthetic fiber surfaces upon deposit of the soil release agent on such surface, said hydrophile segments preferably comprising at least about 25% oxyethylene units and more preferably, especially for such components having about 20 to 30 oxypropylene units, at least about 50% oxyethylene units; or (b) one or more hydrophobe components comprising (i) C₃ oxyalkylene terephthalate segments, wherein, if said hydrophobe components also comprise oxyethylene terephthalate, the ratio of oxyethylene terephthalate: C₃ oxyalkylene terephthalate units is about 2:1 or lower, (ii) C₄-C₆ alkylene or oxy C₄-C₆ alkylene segments, or mixtures therein, (iii) poly (vinyl ester) segments, preferably polyvinyl acetate), having a degree of polymerization of at least 2, or (iv) C₁-C₄ alkyl ether or C₄ hydroxyalkyl ether substituents, or mixtures therein, wherein said substituents are present in the form of C₁-C₄ alkyl ether or C₄ hydroxyalkyl ether cellulose derivatives, or mixtures therein, and such cellulose derivatives are amphiphilic, whereby they have a sufficient level of C₁-C₄ alkyl ether and/or C₄ hydroxyalkyl ether units to deposit upon conventional polyester synthetic fiber surfaces and retain a sufficient level of hydroxyls, once adhered to such conventional synthetic fiber surface, to increase fiber surface hydrophilicity, or a combination of (a) and (b).
Typically, the polyoxyethylene segments of (a)(i) will have a degree of polymerization of from about 1 to about 200, although higher levels can be used, preferably from 3 to about 150, more preferably from 6 to about 100. Suitable oxy C₄-C₆ alkylene hydrophobe segments include, but are not limited to, end-caps of polymeric soil release agents such as MO₃S(CH₂)_nOCH₂CH₂O-, where M is sodium and n is an integer from 4-6, as disclosed in U.S. Patent 4,721,580, issued January 26, 1988 to Gosselink.
Anti-resoiling polymers useful in the present invention also include cellulosic derivatives such as hydroxyether cellulosic polymers, co-polymeric blocks of ethylene terephthalate or propylene terephthalate with polyethylene oxide or polypropylene oxide terephthalate, and the like. Such anti-resoiling polymers are commercially available and include hydroxyethers of cellulose such as METHOCEL® (Dow). Cellulosic anti-resoiling polymers for use herein also include those selected from the group consisting of C₁-C₄ alkyl and C₄ hydroxyalkyl cellulose; see U.S. Patent 4,000,093, issued December 28, 1976 to Nicol, et al.
Anti-resoiling polymers characterised by poly(vinyl ester) hydrophobe segments include graft co-polymers of poly(vinyl ester), e.g., C₁-C₆ vinyl esters, preferably poly(vinyl acetate) grafted onto polyalkylene oxide backbones, such as polyethylene oxide backbones. See European Patent Application 0 219 048, published April 22, 1987 by Kud, et al. Commercially available anti-resoiling polymers of this kind include the SOKALAN® type of material, e.g., SOKALAN HP-22®, available from BASF.
One type of preferred anti-resoiling polymer is a co-polymer having random blocks of ethylene terephthalate and polyethylene oxide (PEO) terephthalate. The molecular weight of this anti-resoiling polymer is in the range of from about 25,000 to about 55,000. See U.S. Patent 3,959,230 to Hays, issued May 25, 1976 and U.S. Patent 3,893,929 to Basadur issued July 8, 1975.
Another preferred anti-resoiling polymers is a polyester with repeat units of ethylene terephthalate units which contains 10-15% by weight of ethylene terephthalate units together with 90-80% by weight of polyoxyethylene terephthalate units, derived from a polyoxyethylene glycol of average molecular weight 300-5,000. Examples of this polymer include the commercially available material ZELCON 5126® (from Dupont) and MILEASE T® (from ICI). See also U.S. Patent 4,702,857, issued October 27, 1987 to Gosselink.
Another preferred anti-resoiling polymer is a sulfonated product of a substantially linear ester oligomer comprised of an oligomeric ester backbone of terephthaloyl and oxyalkyleneoxy repeat units and terminal moieties covalently attached to the backbone. These anti-resoiling polymers are fully described in U.S. Patent 4,968,451, issued November 6, 1990 to J.J. Scheibel and E.P. Gosselink. Other suitable anti-resoiling polymers include the terephthalate polyesters of U.S. Patent 4,711,730, issued December 8, 1987 to Gosselink et al, the anionic end-capped oligomeric esters of U.S. Patent 4,721,580, issued January 26, 1988 to Gosselink, and the block polyester oligomeric compounds of U.S. Patent 4,702,857, issued October 27, 1987 to Gosselink.
Preferred anti-resoiling polymers also include the soil release agents of U.S. Patent 4,877,896, issued October 31, 1989 to Maldonado et al., which discloses anionic, especially sulfoaroyl, end-capped terephthalate esters.
Still another preferred anti-resoiling agent is an oligomer with repeat units of terephthaloyl units, sulfoisoterephthaloyl units, oxyethyleneoxy and oxy-1,2-propylene units. The repeat units form the backbone of the oligomer and are preferably terminated with modified isethionate end-caps. A particularly preferred anti-resoiling agent of this type comprises about one sulfoisophthaloyl unit, 5 terephthaloyl units, oxyethyleneoxy and oxy-1,2-propyleneoxy units in a ratio of from about 1.7 to about 1.8, and two end-cap units of sodium 2-(2-hydroxyethoxy)-ethanesulfonate. Said anti-resoiling agent also comprises from about 0.5% to about 20%, by weight of the oligomer, of a crystalline-reducing stabilizer, preferably selected from the group consisting of xylene sulfonate, cumene sulfonate, toluene sulfonate, and mixtures thereof. See U.S. Pat. No. 5,415,807, issued May 16, 1995, to Gosselink et al.
The liquid compositions may comprise from 0.01% to 10%, preferably from 0.01% to 5%, and more preferably from 0.05% to 2% by weight of the total composition of a further anti-resoiling agent.
A preferred further anti-resoiling agent is an anti-resoiling polymer. A more preferred further anti-resoiling agent is a soil suspending polyamine polymer. An even more preferred further anti-resoiling agent is an alkoxylated polyamine polymer. The most preferred further anti-resoiling agent useful in the compositions herein are selected from the group consisting of : an ethoxylated polyethylene amine according to the formula as described above wherein n=2 and y=20, and an ethoxylated polyethylene amine according to the formula as described herein wherein n=40 and y=7.

Other optional ingredients

The compositions herein may further comprise conventional carpet cleaning ingredients. Preferably, the compositions herein may comprise a number of additional compounds such as volatile organic compounds, surfactants, stabilising agents, chelating agents, builder systems, radical scavengers, perfumes, dyes, suds suppressing agents, enzymes, photobleaching agents, bleach activators and other minors.
In a preferred embodiment, the compositions herein may further comprise a number of additional compounds such as stabilising agents, chelating agents, builder systems, radical scavengers, perfumes, dyes, suds suppressing agents, enzymes, photobleaching agents, bleach activators and other minors.

Volatile organic compounds

As an optional but highly preferred ingredient the compositions according to the present invention may comprise a volatile organic compound (VOC) or a mixture thereof.
Typically, the compositions herein may comprise up to 90%, preferably from 0.1% to 20%, more preferably from 0.5% to 10% and most preferably from 1% to 5% by weight of the total composition of a volatile organic compound or a mixture thereof.
Suitable volatile organic compounds for use herein are selected from the group consisting of : an aliphatic and/or aromatic alcohol; a glycol ether and/or a derivative thereof; a polyol; and a mixture thereof.
Suitable aromatic alcohols to be used herein are according to the formula R₁-OH wherein R₁ is an alkyl substituted or non-alkyl substituted aryl group of from 1 to 20 carbon atoms, preferably from 2 to 15 and more preferably from 2 to 10. A suitable aromatic alcohol to be used herein is benzyl alcohol.
Suitable aliphatic alcohols to be used herein are according to the formula R₂-OH wherein R₂ is a linear or branched saturated or unsaturated hydrocarbon chain of from 1 to 20 carbon atoms, preferably from 1 to 10 and more preferably from 2 to 6. Highly preferred herein are aliphatic alcohols with 2 to 4 carbon atoms and most preferably 4 carbon atoms, or mixtures thereof. Suitable aliphatic alcohols to be used herein include linear alcohol like 2-octanol, decanol, isopropyl alcohol, propyl alcohol, ethanol and/or methanol. Highly preferred herein are ethanol, isopropyl alcohol or a mixture thereof.
Ethanol may be commercially available from Eridania Italia under its chemical name.
Isopropanol may be commercially available from Merck/BDH Italia under its chemical name.
Suitable glycol ethers and/or derivatives thereof to be used herein include monoglycol ethers and/or derivatives thereof, polyglycol ethers and/or derivatives thereof and mixtures thereof.
Suitable monoglycol ethers and derivatives thereof to be used herein include n-buthoxypropanol (n-BP), water-soluble CELLOSOLVE® solvents or mixtures thereof. Preferred Cellosolve® solvents include propoxy ethyl acetate salt (i.e., Propyl Cellosolve acetate salt®), ethanol-2-butoxy phosphate salt (i.e., Butyl Cellosolve phosphate salt®), 2-(Hexyloxy)ethanol (i.e., 2-hexyl Cellosolve®), 2-ethoxy ethanol (i.e., 2-ethyl Cellosolve®), 2-butoxyethanol (i.e., 2-buthyl Cellosolve®) or mixtures thereof.
Suitable polyglycol ethers and derivatives thereof to be used herein include n-butoxypropoxypropanol (n-BPP), butyl triglycol ether (BTGE), butyl diglycol ether (BDGE), water-soluble CARBITOL® solvents or mixtures thereof.
Preferred water-soluble CARBITOL® solvents are compounds of the 2-(2-alkoxyethoxy)ethanol class, 2-(2-alkoxyethoxy)propanol class and/or 2-(2-alkoxyethoxy)butanol class wherein the alkoxy group is derived from ethyl, propyl or butyl. A preferred water-soluble carbitol is 2-(2-butoxyethoxy)ethanol also known as butyl carbitol®.
Preferred glycol ethers and/or derivatives thereof are 2-ethoxyethanol, 2-butoxyethanol, n-butoxypropoxypropanol, butyl carbitol® or mixtures thereof.
Suitable polyol solvents to be used herein are the polyols having at least 2 hydroxyl groups (-OH) like diols. Suitable diols to be used herein include 2-ethyl-1,3-hexanediol, 2,2,4-trimethyl-1,3-pentanediol, methyl-2,4 pentanediol or mixture thereof.
The volatile organic compounds, when present, further contribute to the excellent overall cleaning performance of the present invention. Additionally, their addition in the compositions herein also enhances the sanitising properties of the compositions.

Surfactants

Preferred compositions according to the present invention typically comprise a surfactant or a mixture thereof.
Typically, the compositions herein may comprise up to 50%, preferably from 0.1% to 20%, more preferably from 0.5% to 10% and most preferably from 1% to 5% by weight of the total composition of a surfactant.
Such surfactants may be selected from those well known in the art including anionic, nonionic, zwitterionic, amphoteric and cationic surfactants and mixtures thereof.
Particularly suitable surfactants to be used herein are anionic surfactants. Said anionic surfactants are preferred herein as they further contribute to the outstanding stain removal performance of the compositions of the present invention on various types of stains. Moreover they do not stick on carpet, thereby reducing resoiling.
Suitable anionic surfactants include sarcosinate surfactants, alkyl sulfate surfactants, alkyl sulphonate surfactants, alkyl glycerol sulfate surfactants and alkyl glycerol sulphonate surfactants.
Suitable sarcosinate surfactants to be used herein include acyl sarcosinate or mixtures thereof, in its acid and/or salt form, preferably long chain acyl sarcosinates having the following formula:
wherein M is hydrogen or a cationic moiety and wherein R is an alkyl group of from 11 to 15 carbon atoms, preferably of from 11 to 13 carbon atoms. Preferred M are hydrogen and alkali metal salts, especially sodium and potassium. Said acyl sarcosinate surfactants are derived from natural fatty acids and the amino-acid sarcosine (N-methyl glycine). They are suitable to be used as aqueous solution of their salt or in their acidic form as powder. Being derivatives of natural fatty acids, said acyl sarcosinates are rapidly and completely biodegradable and have good skin compatibility.
Accordingly, particularly preferred long chain acyl sarcosinates to be used herein include C₁₂ acyl sarcosinate, i.e., an acyl sarcosinate according to the above formula wherein M is hydrogen and R is an alkyl group of 11 carbon atom, sodium N-lauroyl sarcosinate, i.e., an acyl sarcosinate according to the above formula wherein M is sodium and R is an alkyl group of 11 carbon atom, and C₁₄ acyl sarcosinate (i.e., an acyl sarcosinate according to the above formula wherein M is hydrogen and R is an alkyl group of 13 carbon atoms). , sodium N-lauroyl sarcosinate is commercially available, for example, as Hamposyl L-30® supplied by Hampshire or Crodasinic LS30® supplied by Croda. C₁₄ acyl sarcosinate is commercially available, for example, as Hamposyl M-30® supplied by Hampshire or Crodasinic MS30® supplied by Croda.
Suitable alkyl sulphonates for use herein include water-soluble salts or acids of the formula RSO₃M wherein R is a C₆-C₂₀ linear or branched, saturated or unsaturated alkyl group, preferably a C₈-C₁₈ alkyl group and more preferably a C₁₀-C₁₆ alkyl group, and M is H or a cation, e.g., an alkali metal cation (e.g., sodium, potassium, lithium), or ammonium or substituted ammonium (e.g., methyl-, dimethyl-, and trimethyl ammonium cations and quaternary ammonium cations, such as tetramethyl-ammonium and dimethyl piperdinium cations and quaternary ammonium cations derived from alkylamines such as ethylamine, diethylamine, triethylamine, and mixtures thereof, and the like).
An example of a C₁₄-C₁₆ alkyl sulphonate is Hostapur® SAS available from Hoechst.
Suitable alkyl sulphate surfactants for use herein are according to the formula R₁SO₄M wherein R₁ represents a hydrocarbon group selected from the group consisting of straight or branched alkyl radicals containing from 6 to 20, preferably 8 to 18, more preferably 10 to 16, carbon atoms and alkyl phenyl radicals containing from 6 to 18 carbon atoms in the alkyl group. M is H or a cation, e.g., an alkali metal cation (e.g., sodium, potassium, lithium, calcium, magnesium and the like) or ammonium or substituted ammonium (e.g., methyl-, dimethyl-, and trimethyl ammonium cations and quaternary ammonium cations, such as tetramethyl-ammonium and dimethyl piperdinium cations and quaternary ammonium cations derived from alkylamines such as ethylamine, diethylamine, triethylamine, and mixtures thereof, and the like).
By "linear alkyl sulphate or sulphonate" it is meant herein a non-substituted alkyl sulphate or sulphonate wherein the alkyl chain comprises from 6 to 20 carbon atoms, preferably from 8 to 18 carbon atoms, and more preferably from 10 to 16 carbon atoms, and wherein this alkyl chain is sulphated or sulphonated at one terminus.
By "branched sulphonate or sulphate", it is meant herein an alkyl chain having from 6 to 20 total carbon atoms, preferably from 8 to 18 total carbon atoms, and more preferably from 10 to 16 total carbon atoms, wherein the main alkyl chain is substituted by at least another alkyl chain, and wherein the alkyl chain is sulphated or sulphonated at one terminus.
Particularly preferred branched alkyl sulphates to be used herein are those containing from 10 to 14 total carbon atoms like Isalchem 123 AS®. Isalchem 123 AS® commercially available from Enichem is a C_12-13 surfactant which is 94% branched. This material can be described as CH₃-(CH₂)_m-CH(CH₂OSO₃Na)-(CH₂)_n-CH₃ where n+m=8-9. Also preferred alkyl sulphates are the alkyl sulphates where the alkyl chain comprises a total of 12 carbon atoms, i.e., sodium 2-butyl octyl sulphate. Such alkyl sulphate is commercially available from Condea under the trade name Isofol® 12S. Particularly suitable liner alkyl sulphonates include C12-C16 paraffin sulphonate like Hostapur® SAS commercially available from Hoechst.
Suitable nonionic surfactants include amine oxide surfactants. Suitable amine oxide surfactants are according to the formula R₁R₂R₃NO, wherein each of R₁, R₂ and R₃ is independently a saturated substituted or unsubstituted, linear or branched alkyl groups of from 1 to 30 carbon atoms, preferably of from 1 to 20 carbon atoms, and mixtures thereof.
Particularly preferred amine oxide surfactants to be used according to the present invention are amine oxide surfactants having the following formula R₁R₂R₃NO wherein R₁ is a saturated linear or branched alkyl group of from 1 to 30 carbon atoms, preferably of from 6 to 20 carbon atoms, more preferably of from 6 to 16 carbon atoms, and wherein R₂ and R₃ are independently substituted or unsubstituted, linear or branched alkyl groups of from 1 to 4 carbon atoms, preferably of from 1 to 3 carbon atoms, and more preferably are methyl groups. Preferred amine oxide surfactants used herein are pure-cut amine oxide surfactants, i.e., a pure single amine oxide surfactant, e.g. C₈ N,N-dimethyl amine oxide, as opposed to mixtures of amine oxide surfactants of different chain lengths
Suitable amine oxide surfactants for use herein are for instance pure cut C₈ amine oxide, pure cut C₁₀ amine oxide, pure cut C₁₄ amine oxide, natural blend C₈-C₁₀ amine oxides as well as natural blend C₁₂-C₁₆ amine oxides. Such amine oxide surfactants may be commercially available from Hoechst or Stephan.
Suitable nonionic surfactants for use herein also include any ethoxylated C₆-C₂₄ fatty alcohol nonionic surfactant, alkyl propoxylates and mixtures thereof, fatty acid C₆-C₂₄ alkanolamides, C₆-C₂₀ polyethylglycol ethers, polyethylene glycol with molecular weight 1000 to 80000 and glucose amides, alkyl pyrrolidones.
Suitable cationic surfactants for use herein include quaternary ammonium compounds of the formula R₁R₂R₃R₄N+ where R₁,R₂ and R₃ are methyl groups, and R₄ is a C_12-15 alkyl group, or where R1 is an ethyl or hydroxy ethyl group, R₂ and R₃ are methyl groups and R₄ is a C_12-15 alkyl group.
Suitable zwitterionic surfactants are zwitterionic betaine surfactants. Suitable zwitterionic betaine surfactants for use herein contain both a cationic hydrophilic group, i.e., a quaternary ammonium group, and anionic hydrophilic group on the same molecule at a relatively wide range of pH's. The typical anionic hydrophilic groups are carboxylates and sulphonates, although other groups like sulfates, phosphonates, and the like can be used. A generic formula for the zwitterionic betaine surfactant to be used herein is : R1-N+(R2)(R3)R4X- wherein R₁ is a hydrophobic group; R₂ is hydrogen, C₁-C₆ alkyl, hydroxy alkyl or other substituted C₁-C₆ alkyl group; R₃ is C₁-C₆ alkyl, hydroxy alkyl or other substituted C₁-C₆ alkyl group which can also be joined to R₂ to form ring structures with the N, or a C₁-C₆ sulphonate group; R₄ is a moiety joining the cationic nitrogen atom to the hydrophilic group and is typically an alkylene, hydroxy alkylene, or polyalkoxy group containing from 1 to 10 carbon atoms; and X is the hydrophilic group, which is a carboxylate or sulphonate group.
Preferred hydrophobic groups R₁ are aliphatic or aromatic, saturated or unsaturated, substituted or unsubstituted hydrocarbon chains that can contain linking groups such as amido groups, ester groups. More preferred R₁ is an alkyl group containing from 1 to 24, preferably from 8 to 18, and more preferably from 10 to 16 carbon atoms. These simple alkyl groups are preferred for cost and stability reasons. However, the hydrophobic group R₁ can also be an amido radical of the formula R_a-C(O)-NH-(C(R_b)₂)m, wherein R_a is an aliphatic or aromatic, saturated or unsaturated, substituted or unsubstituted hydrocarbon chain, preferably an alkyl group containing from 8 up to 20, preferably up to 18, more preferably up to 16 carbon atoms, R_b is selected from the group consisting of hydrogen and hydroxy groups, and m is from 1 to 4, preferably from 2 to 3, more preferably 3, with no more than one hydroxy group in any (C(R_b)₂) moiety.
Preferred R₂ is hydrogen, or a C₁-C₃ alkyl and more preferably methyl. Preferred R3 is C₁-C₄ sulphonate group, or a C₁-C₃ alkyl and more preferably methyl. Preferred R₄ is (CH₂)_n wherein n is an integer from 1 to 10, preferably from 1 to 6, more preferably is from 1 to 3.
Some common examples of betaine/sulphobetaine are described in U.S. Pat. Nos. 2,082,275, 2,702,279 and 2,255,082, incorporated herein by reference.
Examples of particularly suitable alkyldimethyl betaines include coconut-dimethyl betaine, lauryl dimethyl betaine, decyl dimethyl betaine, 2-(N-decyl-N, N-dimethyl-ammonia)acetate, 2-(N-coco N, N-dimethylammonio) acetate, myristyl dimethyl betaine, palmityl dimethyl betaine, cetyl dimethyl betaine, stearyl dimethyl betaine. For example Coconut dimethyl betaine is commercially available from Seppic under the trade name of Amonyl 265®. Lauryl betaine is commercially available from Albright & Wilson under the trade name Empigen BB/L®.
Examples of amidobetaines include cocoamidoethylbetaine, cocoamidopropyl betaine or C₁₀-C₁₄ fatty acylamidopropylene(hydropropylene)sulfobetaine. For example C₁₀-C₁₄ fatty acylamidopropylene(hydropropylene)sulfobetaine is commercially available from Sherex Company under the trade name "Varion CAS® sulfobetaine".
A further example of betaine is Lauryl-immino-dipropionate commercially available from Rhone-Poulenc under the trade name Mirataine H2C-HA®.
A preferred surfactant for use herein is an anionic surfactant or a zwitterionic surfactant or a mixture thereof, a more preferred surfactant is a sarcosinate surfactant, an alkyl sulphonate surfactant, an alkyl sulphate surfactant, an alkyl glycerol sulphate surfactant, an alkyl glycerol sulphonate surfactant or a zwitterionic betaine surfactant and mixtures thereof, an even more preferred surfactant is a sarcosinate surfactant, an alkyl sulphonate surfactant, an alkyl sulphate surfactant, or a zwitterionic betaine surfactant and mixtures thereof, and the most preferred surfactant herein is an alkyl sarcosinate surfactant.
It has been found that poly (vinyl methyl ether / maleic acid) copolymers as described herein can increase the activity of surfactants, preferably anionic surfactants and/or zwitterionic surfactants, most preferably sarcosinate surfactants, when present. Said increase in activity is thought to be due to an interaction of the poly (vinyl methyl ether / maleic acid) copolymer and a surfactant, preferably an anionic surfactant and/or a zwitterionic surfactant, most preferably a sarcosinate surfactant. Said increase in activity further contributes to the overall cleaning performance of the compositions herein.

Stabilizing agents

The compositions of the present invention may further comprise a stabilizing agent selected from the group consisting of hydroxy pyridine N-oxides or derivatives thereof and mixtures thereof.
Suitable hydroxy pyridine N-oxides or derivatives thereof are according to the following formula:
wherein X is nitrogen, Y is one of the following groups oxygen, -CHO, -OH, -(CH₂)n-COOH, wherein n is an integer of from 0 to 20, preferably of from 0 to 10 and more preferably is 0, and wherein Y is preferably oxygen. Accordingly particularly preferred hydroxy pyridine N-oxides or derivatives thereof to be used herein is 2-hydroxy pyridine N-oxide.
Hydroxy pyridine N-oxides or derivatives thereof may be commercially available from Sigma.
Typically, the compositions herein may comprise up to 2%, preferably from 0.001% to 1% and more preferably from 0.001% to 0.5% by weight of the total composition of a hydroxy pyridine N-oxide or derivatives thereof or mixtures thereof.

Chelating agents

The compositions of the present invention may further comprise a chelating agent.
Suitable chelating agents are those known to those skilled in the art. Particularly suitable chelating agents include for examples phosphonate chelating agents, polyfunctionally-substituted aromatic chelating agents, amino carboxylate chelating agents, other chelating agents like ethylene diamine N,N'-disuccinic acid and mixtures thereof.
Typically, the compositions herein may comprise up to 4%, preferably from 0.001% to 1%, and more preferably from 0.001% to 0.5% by weight of the total composition of a chelating agent.
Suitable phosphonate chelating agents to be used herein may include ethydronic acid, alkali metal ethane 1-hydroxy diphosphonates as well as amino phosphonate compounds, including amino alkylene poly (alkylene phosphonate), alkali metal ethane 1-hydroxy diphosphonates, nitrilo trimethylene phosphonates, ethylene diamine tetra methylene phosphonates, and diethylene triamine penta methylene phosphonates. The phosphonate compounds may be present either in their acid form or as salts of different cations on some or all of their acid functionalities. Preferred phosphonate chelating agents to be used herein are diethylene triamine penta methylene phosphonates (DETPMP). Such phosphonate chelating agents are commercially available from Monsanto under the trade name DEQUEST®.
Polyfunctionally-substituted aromatic chelating agents may also be useful in the compositions herein. See U.S. patent 3,812,044, issued May 21, 1974, to Connor et al. Preferred compounds of this type in acid form are dihydroxydisulfobenzenes such as 1,2-dihydroxy -3,5-disulfobenzene.
A preferred biodegradable chelating agent for use herein is ethylene diamine N,N'- disuccinic acid, or alkali metal, or alkaline earth, ammonium or substitutes ammonium salts thereof or mixtures thereof. Ethylenediamine N,N'- disuccinic acids, especially the (S,S) isomer, have been extensively described in US patent 4, 704, 233, November 3, 1987. to Hartman and Perkins. Ethylenediamine N,N'- disuccinic acid is, for instance, commercially available under the tradename ssEDDS® from Palmer Research Laboratories.
Suitable amino carboxylate chelating agents to be used herein include ethylene diamine tetra acetates, diethylene triamine pentaacetates, diethylene triamine pentaacetate (DTPA), N-hydroxyethylethylenediamine triacetates, nitrilotriacetates, ethylenediamine tetrapropionates, triethylenetetraaminehexaacetates, ethanoldiglycines, propylene diamine tetracetic acid (PDTA) and methyl glycine di-acetic acid (MGDA), both in their acid form, or in their alkali metal, ammonium, and substituted ammonium salt forms. A particularly suitable amino carboxylate to be used herein is diethylene triamine penta acetic acid (DTPA).
Other suitable chelating agents to be used herein include salicylic acid or derivatives thereof, or mixtures thereof according to the following formula:
wherein X is carbon, Y is one of the following groups -CHO, -OH, -(CH2)n-COOH, and preferably is -(CH2)n-COOH, and wherein n is an integer of from 0 to 20, preferably of from 0 to 10 and more preferably is 0. Salicylic acid and derivatives thereof may be used herein either in their acid form or in their salts form as for example sodium salts.
Salicylic acid is particularly preferred herein and may be commercially available from Rhone Poulenc.

Bleach activators

In an embodiment of the present invention where the compositions herein comprise a peroxygen bleach, preferably hydrogen peroxide, said compositions may further comprise a bleach activator, as an optional ingredient.
By "bleach activator", it is meant herein a compound which reacts with the peroxygen bleach, preferably hydrogen peroxide, to form a peracid. The peracid thus formed constitutes the activated bleach.
Suitable bleach activators to be used herein include those belonging to the class of esters, amides, imides, or anhydrides. Examples of suitable compounds of this type are disclosed in British Patent GB 1 586 769 and GB 2 143 231 and a method for their formation into a prilled form is described in European Published Patent Application EP-A-62 523. Suitable examples of such compounds to be used herein are tetracetyl ethylene diamine (TAED), sodium 3,5,5 trimethyl hexanoyloxybenzene sulphonate, diperoxy dodecanoic acid as described for instance in US 4 818 425 and nonylamide of peroxyadipic acid as described for instance in US 4 259 201 and n-nonanoyloxybenzenesulphonate (NOBS). Also suitable are N-acyl caprolactam selected from the group consisting of substituted or unsubstituted benzoyl caprolactam, octanoyl caprolactam, nonanoyl caprolactam, hexanoyl caprolactam, decanoyl caprolactam, undecenoyl caprolactam, formyl caprolactam, acetyl caprolactam, propanoyl caprolactam, butanoyl caprolactam pentanoyl caprolactam or mixtures thereof. A particular family of bleach activators of interest was disclosed in EP 624 154, and particularly preferred in that family is acetyl triethyl citrate (ATC). Acetyl triethyl citrate has the advantage that it is environmentally friendly as it eventually degrades into citric acid and alcohol. Furthermore, acetyl triethyl citrate has a good hydrolytical stability in the composition upon storage and it is an efficient bleach activator.
The compositions according to the present invention may comprise up to 30%, preferably from 1% to 20%, and more preferably from 2% to 10% by weight of the total composition of a bleach activator.

Builders

The compositions according to the present invention may further comprise a builder system. Any conventional builder system known in the art is suitable for use herein. Suitable builders for use herein include derivatives of succinic acid of the formula R-CH(COOH)CH₂(COOH) wherein R is C_10-20 alkyl or alkenyl, preferably C_12-16 alkyl or alkenyl, or wherein R can be substituted with hydroxyl, sulpho sulphoxyl or sulphone substituents. Specific examples include lauryl succinate, myristyl succinate, palmityl succinate, 2-dodecenylsuccinate, 2-tetradecenyl succinate. Succinate builders are preferably used in the form of their water-soluble salts, including sodium, potassium, ammonium and alkanolammonium salts.
Other suitable builders are oxodisuccinates and mixtures of tartrate monosuccinic and tartrate disuccinic acid such as described in US 4,663,071.
Further suitable builders for use herein are fatty acid builders including saturated or unsaturated C_10-18 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.
The compositions herein may comprise up to 10%, preferably from 1% to 7% by weight of the total composition of a builder system.

Radical scavengers:

The compositions herein may comprise a radical scavenger as another optional ingredient. Suitable radical scavengers for use herein include the well-known substituted mono and di hydroxy benzenes and derivatives thereof, alkyl- and aryl carboxylates and mixtures thereof. Preferred radical scavengers for use herein include di-tert-butyl hydroxy toluene (BHT), p-hydroxy-toluene, hydroquinone (HQ), di-tert-butyl hydroquinone (DTBHQ), mono-tert-butyl hydroquinone (MTBHQ), tert-butyl-hydroxy anysole (BHA), p-hydroxy-anysol, benzoic acid, 2,5-dihydroxy benzoic acid, 2,5-dihydroxyterephtalic acid, toluic acid, catechol, t-butyl catechol, 4-allyl-catechol, 4-acetyl catechol, 2-methoxyphenol, 2-ethoxy-phenol, 2-methoxy-4-(2-propenyl)phenol, 3,4-dihydroxy benzaldehyde, 2,3-dihydroxy benzaldehyde, benzylamine, 1,1,3-tris(2-methyl-4-hydroxy-5-t-butylphenyl) butane, tert-butyl-hydroxy-anyline, p-hydroxy anyline as well as n-propyl-gallate. Highly preferred for use herein is di-tert-butyl hydroxy toluene, which is for example commercially available from SHELL under the trade name IONOL CP® and/or tert-butyl-hydroxy anysole and/or propyl gallate. These radical scavengers further contribute to the stability of the compositions herein.
Typically, the compositions according to the present invention may comprise up to 5%, preferably from 0.002% to 1.5% by weight and more preferably from 0.002% to 0.5% by weight of the total composition of a radical scavenger.

Experimental data and Examples

The following Examples are meant to exemplify compositions used in a process according to the present invention but are not necessarily used to limit or otherwise define the scope of the present invention.

Data on the benefits associated with the compositions of the present invention

The following compositions were made by mixing the listed ingredients in the listed proportions (weight % unless otherwise specified). The compositions were then used in a process according to the present invention to clean a carpet.
The compositions I-VI described above were tested using the cleaning performance and the anti-resoiling performance tests as described in the section titled : Poly (vinyl methyl ether / maleic acid) copolymer. Composition I is taken as a reference, the other compositions are rated in panel score units against the reference composition I. Composition II is a composition comprising an ethoxylated polyethylene amine (ESP-0620A®), which is an anti-resoiling agent other than the poly (vinyl methyl ether / maleic acid) copolymers as described in the present invention. Compositions III to VI are compositions according to the present invention. Compositions I and II are comparative examples.
The above results clearly show the cleaning and anti-resoiling benefits of a composition according to the present invention (compositions III to VI), i.e., compositions comprising a poly (vinyl methyl ether / maleic acid) copolymer, versus compositions comprising no anti-resoiling polymer (composition I) or compositions comprising other anti-resoiling polymers as claimed herein (composition II).

Examples

The following examples will further illustrate the present invention. The compositions are made by combining the listed ingredients in the listed proportions (weight % unless otherwise specified).
The compositions exemplified above are preferably packaged in a container adapted to deliver a spray of droplets having a particle size distribution with a mean diameter D(v,0.9) of 200 to 400 microns, when measured with Malvern Mastersizer S LongBed ® referenced herein before. A suitable container used was an electrically driven sprayer.
The compositions in the examples above deliver excellent anti-resoiling properties as well as excellent cleaning performance on particulate soil, greasy/oily soil, and/or enzymatic soil as well as on other types of soils.

Claims

A process of cleaning a carpet with a liquid composition comprising a poly (vinyl methyl ether / maleic acid) copolymer.
A process of cleaning a carpet according to claim 1, wherein said process comprises the steps of applying said composition to the surface of the carpet and leaving said composition to substantially dry onto the carpet.
A process of cleaning a carpet according to any of the preceding claims wherein said composition is applied onto the carpet by using a spraying dispenser.
A process of cleaning a carpet according to any of the preceding claims wherein said composition is delivered onto the carpet in the form of a spray of droplets having a particle size distribution with a mean diameter D(v,0.9) of less than 1500 microns.
A process of cleaning a carpet according to any of the preceding claims wherein said poly (vinyl methyl ether / maleic acid) copolymer has the general formula :
wherein n (degree of polymerisation) is an integer of from 50 to 1600.
A process of cleaning a carpet according to any of the preceding claims wherein said poly (vinyl methyl ether / maleic acid) copolymer has an average molecular weight of from 1'000 to 10'000'000.
A process of cleaning a carpet according to any of the preceding claims wherein said composition comprises from 0.001% to 10% by weight of the total composition of said poly (vinyl methyl ether / maleic acid) copolymer.
A process of cleaning a carpet according to any of the preceding claims wherein said composition further comprises a peroxygen bleach.
A process of cleaning a carpet according to claim 8 wherein said composition comprises from 0.01% to 20% by weight of the total composition of said peroxygen bleach.
A process of cleaning a carpet according to any of claims 8 or 9 wherein said peroxygen bleach is selected from the group consisting of : hydrogen peroxide; water soluble sources of hydrogen peroxide; organic or inorganic peracids; hydroperoxides; and diacyl peroxides; and mixtures thereof.
A process of cleaning a carpet according to any of the preceding claims wherein said composition comprises a further anti-resoiling agent.
A process of cleaning a carpet according to claim 11 wherein said further anti-resoiling agent is a soil suspending polyamine polymer.
A process of cleaning a carpet according to any of the preceding claims wherein said composition further comprises a volatile organic compound.
A process of cleaning a carpet according to claim 13 wherein said composition comprises up to 90% by weight of the total composition of a volatile organic compound.
A process of cleaning a carpet according to any of the claims 13 or 14 wherein said volatile organic compound is selected from the group consisting of : an aliphatic and/or aromatic alcohol; a glycol ether and/or a derivative thereof; a polyol; and mixtures thereof.
A process of cleaning a carpet according to any of the preceding claims wherein said composition further comprises a surfactant.
A process according to claim 16 wherein said surfactant is an anionic surfactant, a zwitterionic surfactant or a mixture thereof.
A process according to claim 16 wherein said surfactant is selected from the group consisting of : a sarcosinate surfactant; an alkyl sulphonate surfactant; an alkyl sulphate surfactant; an alkyl glycerol sulphate surfactant; an alkyl glycerol sulphonate surfactant; a zwitterionic betaine surfactant; and mixtures thereof.
A process of cleaning a carpet according to any of the preceding claims wherein said composition further comprises a number of additional compounds such as stabilising agents, chelating agents, builder systems, radical scavengers, perfumes, dyes, suds suppressing agents, enzymes, photobleaching agents, bleach activators and other minors.
The use of a poly (vinyl methyl ether / maleic acid) copolymer as an anti-resoiling agent in a carpet cleaning composition to clean carpets whereby said carpet cleaning composition provides carpet cleaning and/or carpet anti-resoiling benefits.