WO2004015185A1

WO2004015185A1 - Fabric treatment article and corresponding method of using it

Info

Publication number: WO2004015185A1
Application number: PCT/EP2003/008387
Authority: WO
Inventors: Rajan Raghavachari; Bijal Shah
Original assignee: Hindustan Lever Ltd; Unilever NV
Current assignee: Hindustan Unilever Ltd; Unilever NV
Priority date: 2002-08-07
Filing date: 2003-07-21
Publication date: 2004-02-19
Anticipated expiration: 2005-02-07
Also published as: GB0218322D0; GB2406340A; GB2406340B; AU2003250191A1; AR040816A1; ZA200500965B; BR0313256A; GB0501836D0

Abstract

A method of treating a textile fabric with the human hand by contacting the textile with a fabric treatment article designed to be held by the human hand in the presence of water, the article comprising a flexible porous housing, the housing containing at least a solid detergent composition within it and the porous flexible housing is coated on the inside with a bleach ingredient, an enzyme, a perfume, a fluorescer or mixtures thereof. The detergent composition is preferably a bar.

Description

FABRIC TREATMENT ARTICLE AND CORRESPONDING METHOD OF USING IT

TECHNICAL FIELD

The present invention relates to a fabric treatment article for treating textile fabrics with the human hand.

INTRODUCTION

For the purposes of washing textile fabrics the hand wash method remains by far the most widely used washing^' technique around the world. Within the broad definition of ^xhandwash' exist a multitude of different washing techniques, however almost all of these involve an element of rubbing or contacting a detergent composition with the textile fabrics which require washing. Often these detergent compositions are applied directly to the fabrics by hand. In some wash habits, the handwash process is enhanced by the use of additional wash tools such as brushes or solid blocks for beating the fabrics.

Articles for assisting the cleansing of surfaces in general are well-known in the art:

US 4,515,703 (Unilever) discloses an article for wiping surfaces such as household industrial objects or the human skin. US 4,603,069 (Unilever) discloses a sheet-like article suitable for wiping hard surfaces comprising two sheets of nonwoven fabric bonded together by a plurality of small spaced bonding points.

US 6,063,390 (Unilever) discloses a wiping article suitable for cleansing body surfaces which includes an effervescence cleanser composition held within a pouch formed from a first and second substrate sheet, at least one of which is water- permeable.

WO 01 27239 (Procter & Gamble) discloses a semi-enclosed applicator for wiping kitchen surfaces having two sides and an internal cavity with a fluid-impermeable layer adjacent to one of the sides and comprising a liquid cleaning composition which comprises less than 0.5 wt% surfactant.

WO 01 26530 (Procter & Gamble) discloses a semi-enclosed applicator for wiping and cleaning kitchen surfaces having two sides containing a flexible fluid reservoir.

WO 01 29169 (Unilever) discloses a conventional detergent bar encased in a porous flexible housing such as a pouf .

Accordingly, the present inventors have devised a method of washing textile fabrics by hand which utilises a flexible porous housing which contains a solid detergent within it. Such a method results in an increase in detergency when the interior of the housing is coated in high-performance ingredients such as enzymes which are difficult to incorporate into certain solid detergent compositions. DEFINITION OF THE INVENTION

In a first aspect, the invention provides a method of treating a textile fabric with the human hand by contacting the textile with a fabric treatment article designed to be held by the human hand in the presence of water, the article comprising a flexible porous housing, the housing containing at least a solid detergent composition within it and wherein the interior of the housing is coated with a bleach ingredient, an enzyme, a perfume, a fluorescer or mixtures thereof, preferably an enzyme.

In a second aspect, the invention provides a fabric treatment article comprising a flexible porous housing, wherein the inside of the housing is coated in a bleach ingredient, an enzyme, a perfume, a fluorescer or mixtures thereof .

The Flexible Porous Housing

The fabric treatment article of the present invention comprises a flexible water-permeable housing. Such a housing allows the solid detergent composition to be applied more effectively to the fabrics which are intended to be washed. Without wishing to be bound by theory it is understood that the housing reduces the amount of detergent composition which is applied to the fabric but due to its porosity helps to generate more foam. Hence these two aspects provide for at least two technical advantages over using the detergent composition directly. Firstly less composition is used, thereby extending the lifetime of the composition and increasing its cost performance. Secondly the foam which is enhanced by the housing is more easily removed since there is less detergent composition on the surface of the fabric which may otherwise tend to produce further foam during a rinse cycle.

Although the housing is flexible is it is preferred that it is formed from a resilient material which tends to return to its initial state when external forces are released. Hence it is preferred that the article is flexible but resilient. The housing is preferably at least partially made from a non-woven material, preferably rayon.

It is also preferred that the housing has some degree of abrasiveness sufficient to aid the rubbing of textile fabrics but not so abrasive that it becomes painful to use by the hand during a wash process .

In a first embodiment the housing may completely surround the solid detergent composition to prevent it leaving the housing during use. In an alternative embodiment the housing does not completely surround the solid detergent and has an opening. Such an opening will be sufficiently large to allow further solid detergent composition to be added but not so large that it easily leaves the housing during use. Preferably such an opening may be a slit.

Preferably the housing comprises a first and second sheets, wherein at least one sheet is water-permeable and is suitable for wiping textile fabrics, and the housing is sealed continuously along at least 50% of its perimeter. Hence, in this embodiment, the housing may be sealed all along its perimeter or alternatively left incompletely sealed thus forming an opening in the housing. If the housing is left incompletely sealed it is preferred that the housing is sealed continuously along less than 90% of its perimeter, preferably along from 60 to 80% of its perimeter. When the housing does comprise two sheets, in one embodiment one of the sheets is substantially water-impermeable. In another embodiment one sheet is more abrasive than the other to give further flexibility to the treatment of a wider range of textiles.

In order to assist the use of the article still further, the housing may also have a strap which holds the housing against the palm of the human hand during use.

In a further embodiment the article may comprise a pouch- forming sheet which is sealed continuously with the housing along from 50 to 80% of its perimeter thereby forming a compartment for the human hand.

The article is designed for use by the human hand. Preferably therefore the housing is preferably shaped to fit the palm of the hand for ease of use.

The Detergent Composition

The detergent composition which is contained within the housing can be a gel, tablet, bar, powder or paste, but it is preferably a solid detergent. The solid detergent is designed to be rubbed against the fabrics which are desired to be washed. Therefore the detergent comprises a detergent bar, a powder, a tablet or mixtures thereof, preferably a bar. Non-soap detergent bars which are already designed to be rubbed onto fabric textiles are particularly suitable.

If present as a bar it is formed by extrusion of a detergent composition. In preferred embodiments, the composition is extruded using a plodder. In especially preferred embodiments, the composition undergoes a refining step in a refiner or preplodder prior to an extrusion from the plodder.

In this especially preferred embodiment, the composition is picked up by screws in their refiner/pre-plodder and transported through a refiner plate to form "noodles" which are dropped into a hopper seed of a plodder. Preferably, this is kept under reduced pressure to remove any absorbed gases. In the plodder, material picked up from the hopper is transported by a set of screws to a nose cone section of the plodder where the composition is further compacted and forged, under the pressure built up, through an orifice of the required geometry for the final product.

Conditions for the extrusion of a detergent composition to form a bar will be readily apparent to those skilled in the art . Coating of the Housing

One special feature of the present invention is the application of ingredients to the interior wall of the housing which supplement the action of the solid detergent composition. Such materials which are especially useful are those materials which are difficult to incorporate into bars such as a bleach ingredient, an enzyme, a perfume, a fluorescer or mixtures thereof. It is preferred that an enzyme is thus coated since they are particularly difficult to incorporate into bars .

Enzymes tend to deactivate due to shear, temperature, pH and moisture in a bar during processing and thereafter. The use of a housing allows the delivery and substantivity of these do-good ingredients to be increased. Perfumes are notoriously difficult to incorporate into a bar due to the high temperature processing. However the coating of perfume on the interior of the housing provides an excellent solution to this particular problem with bars.

Method of Use

The article of the present invention is primarily intended to be used in the washing of textile fabrics, preferably as part or the whole of a handwash. Alternatively the articles may be used to apply a pretreatment stage before a conventional washing step. The article is used in combination with a solid detergent and is applied to the textile fabric by hand by the action of rubbing. This combination allows an effective method of application of solid detergent and gives an improved foam profile since less detergent is laid down on the fabric for a given detergency result.

Other Detergent Ingredients

The solid detergent composition contains conventional detergent ingredients, notably detergent-active materials (surfactants), and preferably also detergency builders.

Solid detergent compositions in accordance with the invention may suitably comprise from 5 to 60 wt% of detergent-active surfactant, from 10 to 80 wt% of detergency builder, and optionally other detergent ingredients to 100 wt%.

The detergent compositions will contain, as essential ingredients, one or more detergent active compounds (surfactants) which may be chosen from soap and non-soap anionic, cationic, nonionic, amphoteric and zwitterionic detergent active compounds, and mixtures thereof. Many suitable detergent active compounds are available and are fully described in the literature, for example, in "Surface-Active Agents and Detergents", Volumes I and II, by Schwartz, Perry and Berch. The preferred detergent active compounds that can be used are soaps and synthetic non-soap anionic and nonionic compounds. Non-soap anionic surfactants are especially preferred.

Non-soap anionic surfactants are well-known to those skilled in the art. Examples include alkylbenzene sulphonates, particularly linear alkylbenzene sulphonates having an alkyl chain length of Cs-Cis; primary and secondary alkylsulphates, particularly C₈-C₁₅ primary alkyl sulphates; alkyl ether sulphates; olefin sulphonates; alkyl xylene sulphonates; dialkyl sulphosuccinates; and fatty acid ester sulphonates. Potassium salts are generally preferred. A preferred anionic surfactant is linear alkylbenzene sulphonate.

Nonionic surfactants may optionally be present. These include the primary and secondary alcohol ethoxylates, especially the C₈-C₂₀ aliphatic alcohols ethoxylated with an average of from 1 to 20 moles of ethylene oxide per mole of alcohol, and more especially the C₁₀-C₁₅ primary and secondary aliphatic alcohols ethoxylated with an average of from 1 to 10 moles of ethylene oxide per mole of alcohol. Non-ethoxylated nonionic surfactants include alkylpoly- glycosides, glycerol monoethers, and polyhydroxyamides (glucamide) . Cationic surfactants may optionally be present. These include quaternary ammonium salts of the general formula

R₁R₂R₃R₄N X wherein the R groups are long or short hydrocarbyl chains, typically alkyl, hydroxyalkyl or ethoxylated alkyl groups, and X is a solubilising anion (for example, compounds in which R is a C₈-C₂₂ alkyl group, preferably a Cβ-Cio or C₁₂-C₁ alkyl group, R₂ is a methyl group, and R₃ and R₄, which may be the same or different, are methyl or hydroxyethyl groups) ; and cationic esters (for example, choline esters) .

In an especially preferred cationic surfactant of the general formula R₁R₂R₃ X , Ri represents a Cs-Cio or

C₁₂-C₁ alkyl group, R₂ and R₃ represent methyl groups, R₄ presents a hydroxyethyl group, and X represents a halide or methosulphate ion.

Optionally, amphoteric surfactants, for example, amine oxides, and zwitterionic surfactants, for example, betaines, may also be present.

Preferably, the quantity of anionic surfactant is in the range of from 3 to 50% by weight of the total composition. More preferably, the quantity of anionic surfactant is in the range of from 5 to 35 wt%, most preferably from 10 to 30 wt%. Nonionic surfactant, if present, is preferably used in an amount within the range of from 1 to 20 wt%.

The total amount of surfactant present is preferably within the range of from 5 to 60 wt%.

The compositions may suitably contain from 10 to 80 wt%, preferably from 15 to 70 wt%, of detergency builder. Preferably, the quantity of builder is in the range of from 15 to 50 wt%.

The detergent compositions may contain as builder a crystalline aluminosilicate, preferably an alkali metal aluminosilicate, more preferably a sodium aluminosilicate (zeolite) .

The zeolite used as a builder may be the commercially available zeolite A (zeolite 4A) now widely used in laundry detergent powders. Alternatively, the zeolite may be maximum aluminium zeolite P (zeolite MAP) as described and claimed in EP 384 070B (Unilever) , and commercially available as Doucil (Trade Mark) A24 from Crosfield Chemicals Ltd, UK.

Zeolite MAP is defined as an alkali metal aluminosilicate of zeolite P type having a silicon to aluminium ratio not exceeding 1.33, preferably within the range of from 0.90 to 1.33, preferably within the range of from 0.90 to 1.20. Especially preferred is zeolite MAP having a silicon to aluminium ratio not exceeding 1.07, more preferably about 1.00. The particle size of the zeolite is not critical. Zeolite A or zeolite MAP of any suitable particle size may be used.

Also preferred according to the present invention are phosphate builders, especially sodium tripolyphosphate . This may be used in combination with sodium orthophosphate, and/or sodium pyrophosphate .

Other inorganic builders that may be present additionally or alternatively include sodium carbonate, layered silicate, amorphous aluminosilicates .

Most preferably, the builder is selected from sodium tripolyphosphate, zeolite, sodium carbonate, and combinations thereof. Organic builders may optionally be present . These include polycarboxylate polymers such as polyacrylates and acrylic/maleic copolymers; polyaspartates; monomeric polycarboxylates such as citrates, gluconates, oxydisuccinates, glycerol mono-di- and trisuccinates, carboxymethyloxysuccinates, carboxy-methyloxymalonates, dipicolinates, hydroxyethyl iminodiacetates, alkyl- and alkenylmalonates and succinates; and sulphonated fatty acid salts.

Organic builders may be used in minor amounts as supplements to inorganic builders such as phosphates and zeolites. Especially preferred supplementary organic builders are citrates, suitably used in amounts of from 5 to 30 wt%, preferably from 10 to 25 wt%; and acrylic polymers, more especially acrylic/maleic copolymers, suitably used in amounts of from 0.5 to 15 wt%, preferably from 1 to 10 wt% .

Builders, both inorganic and organic, are preferably present in alkali metal salt, especially sodium salt, form. Detergent compositions according to the invention preferably do not contain a bleach system. However, a suitable bleach system may be coated on the inside of the article.

The detergent composition of the present invention may additionally contain fillers to add bulk to the product and/or to bind the product components, especially if the detergent composition is in the form of a bar.

If present, the fillers are generally mineral materials and may be soluble or insoluble. Typical examples include calcite, kaolin, talc, china clay, sodium sulphate or any other salt.

The detergent compositions preferably do not contain enzymes. However, enzymes may be coated on the inside of the article. Suitable enzymes include the proteases, amylases, cellulases, oxidases, peroxidases and lipases usable for incorporation in detergent compositions.

Preferred proteolytic enzymes (proteases) are catalytically active protein materials which degrade or alter protein types of stains when present as in fabric stains in a hydrolysis reaction. They may be of any suitable origin, such as vegetable, animal, bacterial or yeast origin. Proteolytic enzymes or proteases of various qualities and origins and having activity in various pH ranges of from 4-12 are available. Proteases of both high and low isoelectric point are suitable.

Other enzymes that may suitably be present include lipases, amylases, and cellulases including high-activity cellulases such as Carezyme (Trade Mark) ex Novo.

Antiredeposition agents, for example, cellulose esters and ethers, for example sodium carboxymethyl cellulose, may also be present .

The compositions may also contain soil release polymers, for example sulphonated and unsulphonated PET/POET polymers, both end-capped and non-end-capped, and polyethylene glycol/polyvinyl alcohol graft copolymers such as Sokolan (Trade Mark) HP22.

Especially preferred soil release polymers are the sulphonated non-end-capped polyesters described and claimed in WO 95 32997A (Rhodia Chimie) .

The detergent compositions may also include one or more inorganic salts other than builder salts. These may include, for example, sodium bicarbonate, sodium silicate, sodium sulphate, magnesium sulphate, calcium sulphate, calcium chloride and sodium chloride. Preferred inorganic salts are sodium sulphate, sodium chloride, and combinations thereof. The detergent compositions may also contain other inorganic materials , for example, calcite , silica, amorphous aluminosilicate, or clays .

Other ingredients that may be present include solvents , hydrotropes , fluorescers , dyes , photobleaches , foam boosters or foam controllers (antifoams) as appropriate , fabric conditioning compounds , and perfumes .

EXAMPLES

The Treatment Article

Two near-elliptical pieces of porous rayon of major and minor linear dimensions of 10 cm and 14 cm were stitched together around all of the perimeter to form a porous flexible housing. Into one of the pieces a slit of length 7cm was formed centrally along its major axis. The slit allows the insertion of a suitable detergent composition.

II Lather Measurement

A Rin supreme' non-soap detergent bar (commercially available in India) was inserted in the article and was dipped in a petri dish which contained 30 ml of 0°FH (French Hardness) water for 30 seconds. A 30 cm x 10 cm polycotton fabric was then rubbed with the bar alone and also with the bar inserted into the article.

The fabric wash washed in the main wash with 250 ml of appropriate hard water containing a commercial antifoam. The fabric was rubbed 20 times- The resultant foam height was measured immediately and after 5 minutes. The fabric was then rinsed in 500 ml hard water, rubbed 20 times, and the height of the foam measured immediately and after a further 5 minutes . The fabric was then rinsed for a second time in 500 ml hard water, rubbed 20 times, and the height of the foam measured immediately and after a further 5 minutes .

In each case the foam height was measured in three different places and an average was taken.

The following tables give the foam height in mm.

Table 1 : 0 FH main wash water, with article

Table 2 : 0 FH main wash water, without article

Table 3 : 24 FH main wash water, with article

Table 4 : 24 FH main wash water, without article

It is believed that the article allows the cleaning of clothes by applying less detergent . The porosity of the article generates more foam in the main wash but due to the presence of less detergent the foam level drops off dramatically during rinse. This provides consumers with an almost ideal foam profile.

Ill Detergency Tests

Detergency experiments were carried using a Rin supreme bar both alone and inside a article on both on WFK 20D and AS12 test cloths. Detergency was measured with the combination of enzyme, bleach and fluorescer coated on inside surface of the article and also with the coating of these three individual ingredients .

Enzyme - Mix of savinase and lipolase Fluorescer- photine C Bleach - Na Sulphite

One gram of each of these three ingredients were dissolved in 25 ml water. This solution was then applied on the inner part of article on both the sides and allowed to dry. The application of the ingredients was done by uniformly adding the solution on the inside surface of the article. Three such articles were prepared by this method for repetition.

2 30 x 10 cm AS12 monitor was used. The bar inserted in the article was dipped in 25-30 ml water for 30 sees. Before applying the bar (kept inside the article) , the fabric was soaked in 100 ml of 0 FH water. After applying the bar and the brush, the fabric was rinsed twice using 100 ml of water.

Experiments were also carried out with the article but without enzyme, bleach and fluorescer and comparative data was obtained from directly applying the bar on fabric without the use of the article. Table 5

The effect of enzyme, bleach and fluorescer coated separately is given below:

Table 6

It can be seen that the use of article did not increase the detergency whereas it enhanced the lather. It suggests that the abrasion due to the application of the rough side of the article on fabric is not enhancing detergency whereas it enhances lather. However the article enables the enhancement in detergency by allowing the use of enzyme, bleach and fluorescer, which are difficult if not impossible to add to a wash bar alone .

IV Rate of Wear

A 30 cm x 10 cm piece of fabric was dipped in 100 ml of water. The bar, both alone and inside the article, was rubbed on the surface of the fabric for 1 minute . The bar was allowed to dry for an hour. This procedure was repeated five times to give a total of 6 minutes rubbing time. This was repeated three times and an average was taken. The final weight of the bar was measured as a percentage of the initial weight and the results are given below:

Table 7

These results appear to confirm that less detergent is deposited on the fabric when the applicator is used than when it is not . This therefore allows current solid detergent products to be used for a longer period and provide cost savings to the consumer .

Claims

1. A method of treating a textile fabric with the human hand by contacting the textile with a fabric treatment article designed to be held by the human hand in the presence of water, the article comprising a flexible porous housing, the housing containing a detergent composition within it, characterised in that the interior of the housing is coated with a bleach ingredient, an enzyme, a perfume, a fluorescer or mixtures thereof, preferably an enzyme.

2. A method as claimed in claim 1, characterised in that the detergent is a solid detergent.

3. A method as claimed in claim 1 or claim 2, characterised in that the housing contains an opening.

4. A method as claimed in any preceding claim, wherein the housing comprises first and second sheets, characterised in that at least one sheet is water- permeable and is suitable for wiping textile fabrics, and the pouch is sealed continuously along at least 50% of its perimeter.

A method as claimed in claim 4, characterised in that the housing is sealed continuously along less than 90% of its perimeter.

6. A method as claimed in claim 4 or claim 5, characterised in that the pouch is sealed continuously along from 60 to 80% of its perimeter.

7. An article as claimed in claim 4, characterised in that it is sealed along all its perimeter.

8. A method as claimed in any preceding claim, characterised in that at least part of the housing is made from non-woven material.

9. A method as claimed in claim 8, characterised in that at least part of the housing is made from rayon.

10. A method as claimed in any preceding claim, characterised in that the article has a strap attached which holds the article in the palm of the hand during use.

11. A method as claimed in any preceding claim, characterised in that the detergent composition is in the form of a soap or non-soap detergent bar, a powder, a tablet or mixtures thereof, preferably a bar.

12. A fabric treatment article comprising a flexible porous housing, characterised in that the inside of the housing is coated in a bleach ingredient, an enzyme, a perfume, a fluorescer or mixtures thereof.

3. An article as claimed in claim 12, characterised in that the housing comprises a soap or non-soap detergent bar.