WO2001007562A1

WO2001007562A1 - Process for treating fabrics

Info

Publication number: WO2001007562A1
Application number: PCT/EP2000/006868
Authority: WO
Inventors: Karl Burgess; June Kay; Rachel Louise Kelly
Original assignee: Unilever Plc; Unilever N.V.; Hindustan Lever Limited
Priority date: 1999-07-27
Filing date: 2000-07-18
Publication date: 2001-02-01
Also published as: AU5985700A; GB9917620D0

Abstract

A fabric treatment process of the type which employs a carrier sheet having a treatment composition impregnated thereon, which process involves the steps of pretreating at least a portion of the fabric by contacting the sheet with a stained portion of the fabric, placing the pretreated fabric in a dryer along with the carrier sheet, and carrying out a drying operation, the process being characterised in that the carrier sheet includes a defined tear-off portion which is used to pre-treat the fabrics, wherein the tear-off portion is separated from the sheet prior to addition of the sheet to the dryer.

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.

Therefore, there is also a need for a home garment cleaning process and product that does not have the known drawbacks of the Dryel product. Such a product and process would preferably eliminate the need for a garment bag and simplify the stain removal process.

It is also known to use chemicals in clothes dryers to soften, freshen and reduce static on garments. Fabric softener dryer sheets have been used for these purposes for decades and are described, for example, in U.S. Patent Nos . : 4,237,155; 4,238,531; 4,327,133; 4,421,792, 5,094,761; 5,234,610; 5,348,667; and 5,376,287; all of which are incorporated herein by reference. To be effective, however, dryer sheets generally need to interact with damp clothing in order to deliver their intended benefits. As such, these dryer sheets are particularly suited for processing garments after removal from the washing machine and not for dry clothing in need of freshening.

Therefore, there is need for a fabric freshening, softening and/or static removing product that can deliver the desired benefits to relatively dry clothing.

Furthermore, as previously discussed, the ability to reduce or eliminate wrinkles on relatively clean clothing is also desired. Known attempts to reduce wrinkles by means of chemical ingredients in the wash include the use of zwitterionic surfactants, aminosilicones, curable aminosilicones, cellulose enzymes and alkyl amides. However, each of these ingredients have one or more drawbacks. For example, zwitterionic surfactants are believed to work best in cold water. Aminosilicones can cause yellowing and can be difficult to formulate. Curable aminosilicones require the heat of an iron to reduce wrinkles. Cellulase enzymes generally require several wash cycles before anti-wrinkle benefits become noticeable. Alkyl amides are not very effective relative to other wrinkle reducing agents.

In particular the invention relates to a fabric treatment process of the type which employs a carrier sheet having a treatment composition impregnated thereon, which process generally involves the steps of pretreating at least a portion of the fabric by contacting the sheet with a stained portion of the fabric, placing the pretreated fabric in a dryer along with the carrier sheet, and carrying out a drying operation. Such a process is known from PCT Patent Application No. WO 97/32004 in the name of Procter and Gamble.

It is an object of the present invention to provide an improved home dry cleaning process

STATEMENTS OF INVENTION

The Applicants have discovered a further problem associated with the above type of pre-treatment home dry cleaning processes, which problem stems from the fact that the carrier sheet during a pre-treatment operation picks up dirt and soil from the stained fabrics. As the partially soiled carrier sheet is subsequently placed in the dryer with the fabrics, this results in the dirt and soil on the carrier sheet being brought back into contact with the fabrics. This problem is particularly acute when the home dry cleaning process includes the step of placing the fabrics and the carrier sheet in a bag, as the dirt picked up by the carrier sheet during a pre-treatment operation is entrapped within the bag and brought into close contact with the fabrics to be treated.

Accordingly, the present invention is directed towards a home dry cleaning process of the above pre-treatment-type, the process being characterised in that, prior to placing the carrier sheet in the dryer with the fabrics, that portion of carrier sheet which is used in the pre-treatment operation is separated from the carrier sheet. Thus, according to the process of the invention the portion that is used to pre-treat the stained fabric is removed from the main body of the sheet and discarded, while the remaining main body of the carrier sheet, which is unsoiled, is put into the dryer with the pre-treated fabrics. Thus, any dirt and soil picked up during a pre-treatment of the fabrics is not re-introduced to the fabrics during the drying step. The present invention encompasses process where a portion of the carrier sheet is removed prior to, or subsequent to, the pre-treatment step. The critical aspect of the invention is that a soiled pre-treatment portion of the carrier sheet is not placed in the dryer with the fabrics .

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. 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 one embodiment of the invention, the process includes the step of placing the fabrics and carrier sheet in a bag, before placing the bag in the dryer. In one embodiment of the invention the bag comprises means for containing the fabrics and carrier sheet while permitting airflow through the bag. In this regard the bag may be a net bag. Typically the net bag may have a mesh size of between 1 and 100mm.

In a further aspect, the invention relates to a carrier sheet of the type having fabric treatment composition impregnated therein, the carrier sheet being characterised in that it comprises a defined tear-off portion. Ideally, 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.

The invention also relates to a home dry cleaning kit comprising a carrier sheet according to the invention. The kit may also include additional fabric treatment composition, or a containment bag, or both. In a further aspect, the invention relates to a home dry cleaning kit comprising a carrier sheet having a fabric treatment composition impregnated thereon, and a pretreatment article having fabric pre-treatment composition impregnated thereon.

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, with reference to the accompanying drawings in which:

Fig. 1 is a plan view of a carrier sheet according to the invention;

Fig. 2 is a plan view of an alternative construction of carrier sheet; and

Fig. 3 is a plan view of a further construction of carrier sheet . Referring to the drawings there is illustrated a carrier sheet according to the invention, indicated generally by the reference numeral 1, and comprising a single-ply, non-woven, rayon/ polyester sheet having a line of weakening 2 defining a tear-off portion 3. Referring to Figs. 2 and 3 there are illustrated further embodiment of the invention in which parts similar to those described with reference to Fig.l are given the same reference numerals. In Fig 2 the tear-off portion 3 comprises an end of the carrier sheet 1, and in Fig. 3 the tear-off portion is located in a centre of the carrier sheet 1.

When used in a dryer to freshen clothing, it has been found that it preferable to deliver between about 20 and about 60 grams of liquid agent to the dryer load of 1-4 garments. It has further been found that when the above described fabric substrate 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 - il ¬

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 L-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 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 indicates 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 tear-off portion of the substrate, such as a corner, on the stained area, and separating the used tear-off portion from the body of the substrate before placing the body in the dryer with the fabrics. 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.

To freshen clothing, the user simply removes the substrate from the packaging, separate a tear-off portion from the body of the carrier sheet, and use the tear off portion to pre-treat the clothes by rubbing it against the soiled areas as needed. The pre-treated clothes and remainder of the carrier sheet are placed in the dryer while the tear-off portion is discarded. A drying operation is then carried out. Agents 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. In particular, the dirt picked up during the pre-treatment step is removed from the main treatment operation.

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 carrier sheet may not specifically require the tear-off portion to be defined, rather the sheet may be of a material which is easily torn in which case the user may remove any portion which is desired.

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 pretreating at least a portion of the fabric by contacting the sheet with a stained portion of the fabric, placing the pretreated fabric in a dryer along with the carrier sheet, and carrying out a drying operation, the process being characterised in that the carrier sheet includes a defined tear-off portion which is used to pre-treat the fabrics, wherein the tear-off portion is separated from the sheet prior to addition of the sheet to the dryer.

2. A process as claimed in claim 1 in which the tear-off portion is removed from the carrier sheet prior to pretreating the fabrics.

3. A process as claimed in claim 1 in which the tear-off portion is removed from the carrier sheet subsequent to pre-treating the fabrics.

4. A carrier sheet for use in a process as claimed in any of claim 1 to 3 , the carrier sheet comprising a defined tear-off portion.

5. A carrier sheet substantially as hereinbefore described with reference to the accompanying drawings.