EP0240266A2

EP0240266A2 - Fabric treatment products

Info

Publication number: EP0240266A2
Application number: EP87302671A
Authority: EP
Inventors: Donald Bird
Original assignee: Caligen Foam Ltd
Current assignee: Caligen Foam Ltd
Priority date: 1986-03-27
Filing date: 1987-03-27
Publication date: 1987-10-07
Also published as: GB2188341A; GB8607832D0; GB8707397D0; DK158287A; DK158287D0; EP0240266A3

Abstract

A product for the controlled release of a treatment agent comprises a sealed container formed from synthetic foamed plastics material and a particulate treatment agent contained within the container and having particles larger than the pore size of the foam. A preferred product for stain removal purposes incorporates a brightener, a bleach activator and a stain remover soluble in cold water enabling the product to be used in the pre-wash cycle of a washing machine.

Description

This invention relates to products for use in the treatment of fabrics in laundry operations.
It is necessary in the laundering of garments and fabrics to vary laundering conditions and employ differing chemical treatments dependant on the nature of the fabrics concerned and on the extent to which they have been soiled. Fabrics subjected to severe staining, for example, require the application of special stain removing preparations for effective cleaning and many garments are advantageously treated with chemicals imparting a softer texture or feel to the fabrics after cleaning.
Hitherto various difficulties have arisen in applying such chemicals to fabrics in a manner which is effective yet does not subject areas of the fabric to excessive quantities of the chemicals which can result in damage. Such problems are accentuated in modern automatic washing and drying machines where it is often difficult to introduce treatment chemicals at precisely the correct stage in the washing or drying cycle since machines are programmed to carry out sequences of washing and drying operations automatically without operator involvement.
The principal difficulties relate to the control or release of treatment agents so that they act upon the fabrics at the correct times during the laundering cycle yet are uniformly released and dispersed in order not to subject areas of the fabric to excessive treatment which can be damaging. For maximum simplicity it is desirable that the treating agents should be introduced into the machine at the initiation of the laundering cycle but certain agents are best released at subsequent stages and this creates problems in relation to the containment and release of the agents.
Various proposals have been made for containing treating agents to permit their introduction into laundry machines and their release at appropriate times during the laundering cycle. In one such arrangement for use in a dryer, treating agents are contained within a porous pouch or container from which they are gradually released in particle form and dissolve on contact with moisture contained in the fabrics. Such arrangements suffer from the disadvantage that spotting or staining of garments can arise due to the particles of treating agent requiring to be deposited on the garments before they are dissolved.
It has also been proposed to contain treating agents in a pouch or container of fabric construction from which they are released by dissolving but it is difficult with such arrangements to provide for adequate release through the walls of the container during the laundering cycle without the treating agents being released from the container in dry dust form during transportation and storage prior to use.
There accordingly remains a need to find some means of containing treating agents for dispersal among fabrics, garments or the like at appropriate times in a laundering cycle and in a uniformly distributed manner and it is an object of the present invention to provide a product whereby this may be attained.
According to its broader aspects the invention provides a product for the controlled release of a treatment agent, the product comprising a sealed container formed from porous material and a powered or granular treatment agent contained within the container, in which the container is formed from synthetic foamed plastics material and the major proportion of the particles of the treatment agent are larger than the average pore size of the foam so as to be releasable from the container only by permeation through the pores of the foam material when dissolved by an activating agent.
Preferably the container is in the form of a bag or sachet and comprises polyurethane foam.
Preferably the treatment agent is water soluble, such that water acts as said activating agent to dissolve the treatment agent and cause it to permeate through the pores of the foam. The treatment agent may advantageously consist of or include a stain remover.
Preferably the product is soluble in cold water so as to be usable during the pre-wash cycle of a domestic washing machine.
According to a preferred aspect of the invention there is provided a controlled release stain removing product comprising a sealed flexible container in the form of a sachet formed from synthetic foamed plastics material and a cold water soluble stain removing agent in particulate form contained within said sachet, the major proportion of the particles of said stain removing agent being larger than the average pore size of the foam whereby on introduction of the product into the pre-wash cycle of a washing machine the particles of stain removing agent are dissolved by the wash water and released in solution through the pores of the foam into contact with garments or fabrics being washed.
Preferably the agent comprises a fabric treatment product incorporating a brightener, a bleach activator and a stain remover.
The invention also provides a method of treating laundry to remove stains comprising introducing into a washing machine at or before the pre-wash stage of the operating cycle a controlled release product comprising a flexible sachet formed from synthetic foamed plastics material containing a cold-water-soluble stain-removing agent in particulate form in which the major proportion of the particles of said agent are larger than the average pore size of the foam, and operating the machine whereby the particles of the stain-removing agent are dissolved by the wash water and released into solution through the pores of the foam to act upon garments or fabrics contained in the machine.
An embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

Fig. 1 is a plan view of a controlled release product according to the invention; and
Fig. 2 is a cross-section through the product on the line II - II in Fig. 1.

Referring to the drawings, the product comprises a sachet 5 of foamed plastics material such as polyurethane foam which is sealed around its peripheral edges 6 to form a cavity 7 within which is enclosed a powdered treatment agent 8. The particle size of the treatment agent relative to the cell size of the foam from which the sachet is formed is such that the powdered agent cannot permeate through the sachet in its dry state. It will be appreciated that due to variations in cell size and in particle size of the agent some degree of permeation or "dusting" may take place in the dry state. Essentially however the maximum cell size and the minimum particle size are selected to minimise dry release and contain the particles of treatment agent within the sachet until released by dissolving as described hereafter.
The treatment agent comprises a water soluble composition incorporating a brightener, a bleach activator and a stain remover. The agent is soluble in cold water and when contacted with fabrics the solution effects removal of stains, brightens the colouring of the fabric and enhances the cleaning effect of conventional washing powders by activating the bleaches in such powders at lower temperatures than would otherwise be the case. The sachet contains sufficient quantity of treatment agent to effect such treatments to a normal wash load in a domestic washing machine.
In use of the product it is placed into a washing machine drum together with clothes or fabrics to be washed when the drum is loaded. The machine is then set to carry out a pre-wash cycle in cold water (generally between 0 °C and 25 °C). This dissolves the agent within the sachet thus releasing the combined brightener, stain remover and bleach activator into the water in the machine in solution by permeation through the pores of the foam and hence into contact with the fabrics or clothes being cleaned.
Since it is necessary for the agent to dissolve before it can release from the surrounding sachet, the product avoids the problem of particles of the agent coming into direct contact with areas of the fabrics and thereby subjecting them to excessive chemical action resulting in damage. The agent permeates through the cells or pores of the sachet in the form of a solution which is dispersed through the wash water and thus applied uniformly to the fabrics in the machine.
By virtue of the stain removing component the product effects a stain removing action during the pre-wash cycle thereby removing particularly severe staining before the fabrics are subjected to normal wash cycles. The brightener enhances the colouring of the fabrics and the bleach activator improves the effectiveness of the washing powder employed in the pre-wash cycle which otherwise would be less effective than in normal washing cycles due to the low temperature of water employed in prewashing.
By virtue of the sachet form of the product it is readily handleable and the correct quantities of several treatment agents are automatically applied to each wash load by introduction of a single sachet. There is thus no requirement on the part of the operator to measure individual quantities of the agents concerned and the possibility of error through utilizing incorrect proportions or excessive overall quantities of the agents is eliminated. Moreover since the treatment agent permeates through the walls of the sachet only when dissolved in the wash water, problems of dusting, seepage or other escape of treatment agent before it is introduced into the washing machine are eliminated.
While the proportions of constituents in the treatment agent may be varied dependant on differing requirements, in a preferred composition for general domestic washing purposes the agent is made up as follows (percentages by weight);
Stain Remover - 65% to 85%
Bleach Activator - 10% to 20%
Brightener - 5% to 15%
Particularly effective results have been attained utilizing a composition comprising approximately 75% of stain remover, 15% of bleach activator and 10% of brightener. The stain remover, bleach activator and brightener may comprise any known agents of these kinds suitable for use in domestic washing machines and which are compatible in the sense that they do not neutralize one another, delay or interfere with their respective functions or react in a manner producing undesirable effects on the garments or fabrics being washed. Suitable stain removers include the biological enzymio degradation products and fuller's earth.
The sachet may be constructed from a variety of synthetic foamed plastics materials. The preferred material however is a synthetic polyurethane foam having a density of 13-30 kilograms per cubic metre and from 20-60 or preferably from 45-55 cells per 25 mm. Other densities of foam may be employed dependant on the nature of the treating agent and the conditions under which it is to be released. In some instances the agent may be granulated rather than powered and the rate of release may be controlled by use of sachet forming foam materials of different porosity.
In an alternative product for laundry use the treatment agent may consist solely of stain remover, thereby providing a product which may be introduced into the pre-wash of a washing machine only in those cases where the user recognises that the fabrics or garments or certain of them have been subjected to severe staining and require additional treatment to produce effective cleaning. An alternative product for laundry use may incorporate a treatment agent in the form of a fabric softener designed to be released during the normal wash cycle of a washing machine and soluble in warm water (between about 25 °C and 50 °C) but not necessarily in cold water. In such a case fabric softener is either released in the pre-wash cycle and attaches itself to the garments before commencement of the wash cycle, or remains in the sachet through to the wash cycle when it is dissolved in the warm water of the wash cycle and released from the sachet into contact with the garments or fabrics being washed. Other fabric treating agents which may be employed in a similar manner either singly or in combination include anti-static, lubricating, bacteriostatic, mildew-proofing or moth-proofing agents and water-proofing agents.
By virtue of the arrangements described treatment agents may be held in a conveniently handleable form and without being activated until such time as they are introduced into conditions which effect activation and permit release of the agent by permeation through the cells or pores of the container in which it is enclosed. The products are of a readily handleable form and have the advantage that predetermined quantities of treatment agent may be incorporated thereby enabling precisely accurate amounts to be employed without requiring the user to effect measurement or control over the quantities used. This is particularly advantageous in relation to fabric treating agents where the proportions and quantities of different agents require to be critically controlled. Complex combinations of treating agents may therefore be utilized which could not be readily incorporated individually by hand, and the dangers resulting from direct impingment of undissolved product on to areas of fabric or clothing are automatically avoided.
Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.

Claims

1. A product for the controlled release of a treatment agent, the product comprising a sealed container formed from porous material and a powered or granular treatment agent contained within the container, characterised in that the container (5) is formed from synthetic foamed plastics material and the major proportion of the particles of the treatment agent (8) are larger than the average pore size of the foam so as to be releasable from the container only by permeation through the pores of the foam material when dissolved by an activating agent.

2. A product according to claim 1 characterised in that said container (5) is in the form of a bag or sachet.

3. A product according to claim 1 or 2 characterised in that said container (5) comprises polyurethane foam.

4. A product according to any preceding claim characterised in that said agent (8) is water soluble, such that water acts as said activating agent to dissolve the treatment agent and cause it to permeate through the pores of the foam.

5. A product according to any preceding claim characterised in that said treatment agent (8) is soluble in cold water so as to be usable during the pre-wash cycle of a domestic washing machine.

6. A product according to any preceding claim characterised in that said treatment agent (8) consists of or includes a stain remover.

7. A controlled release stain removing product comprising a sealed flexible container in the form of a sachet characterised in that said sachet (5) is formed from synthetic foamed plastics material and a cold water soluble stain removing agent (8) in particulate form is contained within said sachet, the major proportion of the particles of said stain removing agent being larger than the average pore size of the foam whereby on introduction of the product into the pre-wash cycle of a washing machine the particles of stain removing agent are dissolved by the wash water and released in solution through the pores of the foam into contact with garments or fabrics being washed.

8. A product according to any preceding claim characterised in that said agent (8) comprises a fabric treatment product incorporating a brightener, a bleach activator and a stain remover.

9. A product according to claim 8 characterised in that it comprises 65-85% stain remover, 10-20% bleach activator and 5-15% brightener.

10. A product according to claim 8 characterised in that it comprises approximately 75% stain remover, 15% bleach activator and 10% brightener.

11. A product according to any preceding claim characterised in that sufficient agent (8) is present to treat a single wash load in a domestic washing machine, the product being discarded after use.

12. A product according to any preceding claim characterised in that said foamed plastics material has a density of 13-30 kilograms per cubic metre.

13. A product according to any preceding claim characterised in that said foamed plastics material has 20-60 cells per 25 mm.

14. A product according to any preceding claim characterised in that said foamed plastics material has 45-55 cells per 25 mm.

15. A product according to any preceding claim characterised in that it includes a further treatment agent soluble in cold water.

16. A product according to any preceding claim characterised in that it includes a further treatment agent soluble in warm water but not in cold water.

17. A product according to claim 15 or 16 characterised in that said agent is selected from one or more of fabric softening, anti-static, lubricating, bacteriostatic, mildew-proofing, moth-proofing and water-proofing agents.

18. A method of treating laundry to remove stains characterised by introducing into a washing machine at or before the pre-wash stage of the operating cycle a controlled release product comprising a flexible sachet (5) formed from synthetic foamed plastics material containing a cold-water-soluble stain-removing agent (8) in particulate form in which the major proportion of the particles of said agent are larger than the average pore size of the foam, and operating the machine whereby the particles of the stain-removing agent are dissolved by the wash water and released into solution through the pores of the foam to act upon garments or fabrics contained in the machine.

19. A method according to claim 18 characterised in that said agent (8) also incorporates a bleach activator and a brightener.

20. A method according to claim 18 or 19 characterised in that said product also incorporates an agent which is soluble in warm water but not in cold water and the product is left in the machine through to at least the wash cycle of the machine.