[0001] This invention relates to products for use in the treatment of fabrics in laundry
operations.
[0002] 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.
[0003] 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.
[0004] 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.
[0005] 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.
[0006] 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.
[0007] 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.
[0008] 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.
[0009] Preferably the container is in the form of a bag or sachet and comprises polyurethane
foam.
[0010] 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.
[0011] Preferably the product is soluble in cold water so as to be usable during the pre-wash
cycle of a domestic washing machine.
[0012] 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.
[0013] Preferably the agent comprises a fabric treatment product incorporating a brightener,
a bleach activator and a stain remover.
[0014] 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.
[0015] 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.
[0016] 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.
[0017] 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.
[0018] 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.
[0019] 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.
[0020] 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.
[0021] 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.
[0022] 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.
[0023] 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.
[0024] 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.
[0025] 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.
[0026] 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.
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.