WO2001007706A1

WO2001007706A1 - Process for treating fabrics

Info

Publication number: WO2001007706A1
Application number: PCT/EP2000/006869
Authority: WO
Inventors: Karl Burgess; June Kay; Rachel Louise Kelly; Colin Watt Kerr; Jonathan Frank Warr
Original assignee: Unilever Plc; Unilever Nv; Hindustan Lever Limited
Priority date: 1999-07-27
Filing date: 2000-07-18
Publication date: 2001-02-01
Also published as: AU6695200A; GB9917625D0

Abstract

A fabric treatment process of the type, which employs a carrier sheet having a treatment composition impregnated thereon, is described. The process involves the steps of placing the pretreated fabric in a dryer along with the carrier sheet, and carrying out a drying operation. The containment bag includes a plurality of apertures which are of sufficient size to allow substantially uncontrolled, free movement of vapour and gasses through the walls of the bag.

Description

PROCESS FOR TREATING FABRICS

Introduction

The invention relates to a process for treating fabrics.

Background

Commercial products available for the care of clothing and fabrics in the home are well known. These products include liquid, powder and tablet detergents, liquid and sheet fabric softeners and other various products. Professional services, such as dry cleaners, are also widely available for cleaning garments subject to shrinkage or for those that are too delicate for common washer/dryer cycles. Typically, desired results from dry cleaning/laundering clothing is stain removal, odor removal, softening, static removal and reduced wrinkling.

It is not uncommon for a garment that has recently been cleaned but briefly used to lose those properties that are generally associated with freshly cleaned clothing. Indeed, depending on the environment a fabric is subjected to, odors, wrinkles, small stains and the like can quickly render the fabric "unclean" in the eye of the user. For example, a relatively brief exposure to tobacco smoke can leave a noticeable lingering odor on otherwise clean clothing. It is also common for clean clothing to become wrinkled before they are worn, such as when the clothes are packed in a suitcase for travel. Typically, these otherwise clean clothes are either tolerated by the user or sent back through an entire cleaning process.

Therefore, there is a need for a convenient, cost effective and efficient means for reviving clothing that is not in need of a complete laundering or dry cleaning cycle. At least one commercially available product marketed by The Procter & Gamble Company under the name "Dryel", seeks to allow for treatment of clothing in the home dryer. U.S. Patent No. 5,681,355 is marked on the product and is incorporated herein by reference. The Dryel product consists of a plastic bag, a premoistened cloth, bottled stain removal solution and an absorbent pad for use with the stain removal solution. The user is instructed to: 1) completely remove spots and stains prior to placing garments in the bag, preferably by placing the absorbent pad under the garment; 2) add one to four garments to the bag; 3) insert a pre-moistened cloth into the bag containing the garments; 4) seal the bag; 5) tumble the bag, garments and cloth in the dryer for 30 minutes at medium to high heat; and 6) hang the garments promptly to help decrease wrinkling. Users of the Dryel product have complained about the need for a bag and its limited capacity and the potential for entrapment, rather than removal, of particulates . Also, the use of the bottle/pad combination to remove stains adds to the complexity of the process.

Other fabric treatment processes of this general type are known. For example, WO 97/30580 and WO 97/07278, both in the name of Procter and Gamble, disclose fabric treatment processes of the above type which utilise a containment bag which is vapour impermeable. A problem associated with the use of such bags is that the volatilised malodorous material removed from the fabrics during the drying process are unable to escape from the bag, and hence are undesirably re- deposited thereon. In a later patent application,

W097/27354, a solution to the above problem was proposed in the form of a bag having a specific vapour venting range which was carefully controlled to allow venting of malodours while being "closed" enough to allow billowing of the bag and tumbling of the fabrics therein. In effect, while this resulted in some removal of malodours, it has been observed that such bags become soiled over time with dirt, lint and fluff. In addition, the use of such bags results in greater creasing of the clothes contained therein, and a reduction in the quality and quantity of the perfume components available from the treatment composition impregnated onto the carrier sheet.

Therefore, there is a need for a home garment cleaning process and product that overcomes at least some of the above problems.

STATEMENTS OF INVENTION

According to the invention there is provided a fabric treatment process of the type which employs a carrier sheet having a treatment composition impregnated thereon, which process involves the steps of placing one or more fabric articles in a bag along with the carrier sheet before placing the bag in a dryer and carrying out a drying operation, the process being characterised in that the bag includes a plurality of apertures which allows substantially uncontrolled, free movement of vapour and gasses through the walls of the bag while constraining the fabric articles and carrier sheet within the bag. Thus, the apertures in the bag will be of sufficient size, or number, or both, so as to allow fabrics contained the bag to be laundered in a domestic washing machine while in the bag.

Preferably, the apertures comprise at least 50% of a surface area of the bag. Typically, the bag is a net bag, which suitably will have an average mesh size of between 1mm and 100mm, generally between 1 and 50mm, ideally between 1 and 10mm. Alternatively, the bag may comprise a polymeric material having the apertures punched therein. The holes may be of any size to have the required functional effect, however holes in above size ranges are envisaged. In one embodiment of the invention the bag includes a mouth having an optional closure, wherein the process optionally includes the step of closing the bag prior to placing the bag with the fabric articles contained therein in the dryer. Typically, the closure may comprise a drawstring and, optionally, a locking toggle.

The invention also relates to a bag for use in the process of the invention, the bag having a plurality of apertures of sufficient size so as to allow substantially uncontrolled, free movement of vapour and gasses through the walls of the bag. In a further aspect, the invention relates to a fabric treatment kit comprising a containment bag according to the invention, optionally a carrier sheet having fabric treatment composition impregnated thereon, and optionally a container of fabric treatment composition.

In a preferred embodiment of the invention the carrier sheet comprises a defined tear-off portion which is easily separated from the body of the carrier sheet and which is used to pre-treat the fabric prior to being discarded. In this regard any soil which is picked up during a pre- treatment operation is not placed in the dryer. The tear-off portion may be of any size or shape and may form any part of the carrier sheet. For example, the tear off portion may be defined by an edge of the carrier sheet and by a perforated tear line. Alternatively, the tear-off portion may be wholly defined by a perforated tear line. In one embodiment of the invention, the tear-off portion may have impregnated thereon a treatment composition, which is partially suited for pre-treatment operation, or a higher concentration of treatment composition relative to the carrier sheet. In a further embodiment of the invention, the tear-off portion may have a textured surface suitable for a pre-treatment operation. Alternatively, the carrier sheet may have a plurality of tear-off portions, which in one aspect of the invention may have impregnated thereon-different treatment compositions. For example, one tear-off portion may carry a treatment composition which is particularly suited for treating fatty stains, whereas another may carry a treatment composition particularly suited for wine or the like.

In a further aspect, the carrier sheet comprises a single- ply non-woven sheet, which typically comprises a hydroentangled rayon/polyester mix. Generally, the carrier sheet will carry from 10 to lOOg of treatment composition, typically between 20 and 60g, and ideally approximately 40g. Preferably, the treatment composition includes at least perfume and detergent . In one embodiment of the invention the composition comprises an anti -wrinkling agent. One particularly suitable anti-wrinkling agent is marketed under the Trade Name Sil et. In a particularly preferred embodiment of the invention, a portion of the carrier sheet, or indeed a separate carrier sheet, may carry a net charge so as to attract and entrap particulates . Suitably, the charged portion of the carrier sheet may comprise fibres known as "electret" fibres. In one embodiment of the invention, one part of the carrier sheet may comprise a non- woven, hydroentangled, rayon polyester mix, wherein a second part may comprise charged fibres.

DETAILED DESCRIPTION OF THE INVENTION

The invention will be more clearly understood from the following description of some embodiments thereof, given by way of example only.

To freshen clothing, the user simply removes the carrier sheet substrate from the packaging, places it in a containment bag, in this case a net bag having an average mesh size of 15mm, places the fabrics to be treated in the bag before closing the bag using a drawstring closure on the bag, placing the bag in a dryer and carrying out a drying operation. The treatment composition impregnated on the carrier sheet will act on the clothing to reduce wrinkles, reduce odors, reduce stains and/or reduce static. During this process the substrate can contact the inner surfaces of the dryer. The process, as previously discussed, is effective and suitable for use on relatively dry clothing.

When used in a dryer to freshen or otherwise treat clothing, it has been found that it preferable to deliver between about 20 and about 60 grams of liquid fabric treatment agent to a dryer load of 1-4 garments. It has further been found that when the carrier sheets are in a dimension of approximately 12" x 12" and have a dry weight of about 3.5g per square yard, 40 grams of liquid material can absorbed thereon and be properly delivered to the dryer (about 0.29 grams per square inch) . If 45 grams of liquid are desired, this calculates to about 0.31 grams per square inch. In embodiments where the fabric substrate is 12" x 12" , and the preferred liquid quantity is between 20 and 60 grams, the substrate delivers approximately 0.14 grams per square inch to about 0.42 grams per square inch.

As such, once a preferred quantity of liquid to be delivered to the dryer is known, it is possible to determine the area of substrate required. In addition, if a heavier substrate is used, it is possible to deliver greater quantities of liquid to the dryer without increasing the length and width dimensions of the substrate. As previously discussed, while the preferred substrates disclosed herein are square, it is clearly within the scope of the present invention that other shapes, such as circles, triangles and odd shapes, can also be used to deliver the proper amount of liquid. Several molecules have been identified for wrinkle reduction and other benefits, such as static reduction benefits when included on one of the above- identified substrates and used on clothing in a dryer. Using the American Association of Textile Chemists and Colorists (AATCC) method # 124 (described in greater detail, below), the following molecular classes were found to be effective on test cloths: ethoxylated organosilicones ; polyalkyleneoxide modified polydimethylsiloxane; linear aminopolydimethylsiloxane polyalkyleneoxide copolymers; sulfated/sulfonated vegetable oils; high molecular weight polyacrylamides; betaine siloxane copolymers; and alkylactam siloxane coplymers . Of the foregoing, the most preferred wrinkle reducing agent is a polyalkyleneoxide modified polydimethyl siloxane sold under the name Silwet -7622, available from Witco,

Greenwich, CT. Adogen 66, a tallow alkyl BIS (polyethoxy) ethyl ammonium, ethyl sulfate, also available from Witco can be used in combination with one or more of the above compounds to reduce static. Use with Silwet L-7622 is preferred.

One or more of the molecules/compounds from the above- identified classes are preferably formulated in an amount from about 0.1 wt % to about 5 wt % and most preferably from about 0. 3 wt % to about 1.5 wt %. Particularly preferred examples are set forth, below. Formulation 1

Formulation 2

Test Methods and Examples

A preferred method of measuring wrinkle reduction is by using the American Association of Textile Chemists and Colorists' (AATCC) method # 124, Appearance of Fabrics after Repeated Home Laundering. In this method, four cloth types (silk, rayon, cotton, and linen) are washed, dried and stored in a well-defined way. The dried cloths are then evaluated for wrinkle content by comparison with wrinkle smoothness replicas, which can be purchased from AATCC.

Factors such as the light used, the angle of the cloths and replicas to the light, and the background are carefully controlled and described in the method. There are six replicas with values of 1, 2, 3, 3.5, 4, and 5 with 5 being perfectly smooth and 1 being very wrinkled. Three trained observers are asked to give a value of 1-5, to the nearest 0.5 unit, to each cloth based on which replica it most closely resembles. The results are totaled and averaged over the three observers for each cloth type. According to the method, a difference of > 0. 17 between the results for two products indicate there is a significant difference at the 95% confidence level . A difference of greater than or equal to 0.25 indicates a significant difference at the 99% confidence level .

Laboratory tests have shown that when the above formulations are absorbed onto a substrate, such as shown in the figures, and placed in a dryer with clothing, one or more of the identified clothing benefits are achieved. In addition, the formulations have been found effective in stain removal.

Stain removal can be achieved before the dryer is activated by rubbing a portion of the substrate, such as a corner, on the stained area.

The substrate having formulation absorbed therein is preferably enclosed in a hermetically sealed pouch. The pouch will preferably inhibit egress of the chemical agents and inhibit ingress of bacteria and other foreign matter. One or more of the pouches can be packed in an enclosed carton for commercial sale. The pouch is preferably manufactured from a heat sealable, foil laminate material.

The invention is not limited to the embodiments hereinbefore described which may be varied in both construction, detail and process step without departing from the spirit of the invention. In this regard the invention includes a process wherein a user places the treatment composition on the carrier sheet prior to placing the carrier sheet in the dryer .

Claims

1. A fabric treatment process of the type which employs a carrier sheet having a treatment composition impregnated thereon, which process involves the steps of placing one or more fabric articles in a bag along with the carrier sheet before placing the bag in a dryer and carrying out a drying operation, the process being characterised in that the bag includes a plurality of apertures which allows substantially uncontrolled, free movement of vapour and gasses through the walls of the bag, while constraining the fabric articles and the carrier sheet within the bag.

2. A process as claimed in claim 1 in which the apertures comprise at least 50% of a surface area of the bag.

3. A process as claimed in claims 1 or 2 in which the bag is a net bag.

4. A process as claimed in claim 3 in which the net bag has an average mesh size of between 1mm and 100mm.

5. A process as claimed in claims 1 or 2 in which the bag comprises a polymeric material having the apertures formed therein.

6. A process as claimed in any preceding claim in which the bag includes a mouth having an optional closure, wherein the process optionally includes the step of closing the bag prior to placing the bag with the fabric articles contained therein in the dryer.

7. A process substantially as hereinbefore described with reference to the accompanying examples.

8. A bag for use in a process of any of claims 1 to 7, the bag having a plurality of apertures of sufficient size so as to allow substantially uncontrolled, free movement of vapour and gasses through the walls of the bag.

9. A fabric treatment kit comprising a bag as claimed in claim 8, the kit optionally including a carrier sheet having treatment composition impregnated thereon.