AN APPARATUS FOR THE BIOCIDAL TREATMENT OF LAUNDRY

DISPOSITIF DE TRAITEMENT BIOCIDE DE LINGE

English Abstract

The invention relates to a device for the treatment of laundry using biocides in a washing machine, comprising a hollow body (1, 2), in which a biocide substance is enclosed, and the cup of which has openings for the through-flow of the detergent and rinsing agent liquors. The biocide substance is selected such that it is at least substantially harmless to the human metabolism and effective in the laundered products for a certain time period beyond the washing process.

French Abstract

La présente invention concerne un dispositif de traitement biocide de linge dans un lave-linge, lequel dispositif est composé d'un corps creux (1, 2) qui renferme une substance biocide et dont la coque présente des ouvertures permettant le passage de l'eau de lavage et de l'eau de rinçage. La substance biocide est choisie de manière à être au moins dans la mesure du possible non toxique pour le métabolisme humain et pour être efficace dans le linge lavé pendant un certain temps au-delà du processus de lavage.

Claims

CLAIMS:
1. An apparatus for the biocidal treatment of laundry in a
washing machine, characterized in that a biocidal substance is
enclosed in a hollow body (1, 2) whose shell has openings (4)
for the passage of the washing and rinsing baths.
2. An apparatus according to claim 1, characterized in that
the hollow body consists of two half shells (1, 2) which are
latched together.
3. An apparatus according to claim 1 or 2, characterized in
that the hollow body consists of plastic.
4. An apparatus according to one of the claims 1 to 3,
characterized in that the hollow body consists of an inner
shell (1.1, 2.1) and an outer shell (1.2, 2.2).
5. An apparatus according to claim 4, characterized in that
the inner shell (1.1, 2.1) consists of a plastic that ensures
mechanical strength, especially a glass-fiber reinforced
polypropylene, and the outer shell (1.2, 2.2) consists of
thermoplastic elastomer.
6. An apparatus according to one of the claims 1 to 5,
characterized in that the openings in the hollow body shell
consist of two mutually opposite sets of holes (4), having
diameters of between 0.5 mm and 5 mm.
7. An apparatus according to one of the claims 1 to 6,
characterized in that an indicator is embedded in at least one
location in the hollow body shell (1, 2), which indicator
indicates the end of the period of use of the apparatus by
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changing color.
8. An apparatus according to one of the claims 1 to 7,
characterized in that the hollow body is a hollow sphere (1,
2).
9. An apparatus according to one of the claims 1 to 8,
characterized in that the biocidal substance consists of
nanoscale particles on carrier materials or is embedded in the
same.
10. An apparatus according to one of the claims 1 to 9,
characterized in that the biocidal substance is effective in
direct contact with water.
11. An apparatus according to one of the claims 1 to 10,
characterized in that the biocidal substance comprises metal
ions.
12. An apparatus according to claim 11, characterized in that
the ions are at least one of the metals Ag, Cu, Zn, Au, Ir, Pd,
Ti, Al and Sn.
13. An apparatus according to one of the claims 1 to 10,
characterized in that the biocidal substance comprises
quaternary ammonium compounds, triclosan, isothiazoline,
antibiotics, chitosan or mixtures thereof.
14. An apparatus according to one of the claims 1 to 10,
characterized in that the biocidal substance comprises
formaldehyde, ozone, oxygen, chlorine or mixtures thereof
which are released in contact with water.
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15. An apparatus according to claim 9 or 10, characterized in
that the biocidal substance comprises mixtures of the groups
of substances of claims 11 to 14.
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Description

CA 02680068 2009-09-04 04528P0100CA01
AN APPARATUS FOR THE BIOCIDAL TREATMENT OF LAUNDRY
The invention relates to an apparatus for the biocidal
treatment of laundry in a washing machine.
Numerous substances of biocidal effect are known, i.e. such
which have a killing or at least growth-retarding effect on
microorganisms such as bacteria, viruses, fungi and/or spores.
Suitable substances, i.e. such which have a biocidal effect in
suitable dosing, but which are at least substantially harmless
for the human organism and especially human metabolism, can be
added for example by means of a dosing apparatus to the
detergent or can be entered directly into the drum upon
loading the same with laundry. A biocidal treatment of each
batch of laundry in this manner is both laborious and entails
the risk of underdosage or overdosage.
The invention is based on the object of providing an apparatus
that is easy to handle for biocidal treatment of laundry in a
washing machine, especially a domestic washing machine.
This object is achieved in accordance with the invention in
such a way that a biocidal substance is enclosed in a hollow
body whose shell comprises openings for the passage of the
washing and rinsing baths.
The hollow body contains a biocidal substance whose type,
composition and optionally carrier structure is chosen by the
manufacturer in such a way that it is released continually
into an aqueous medium, i.e. the washing and/or rinsing baths
of the washing machine, in an effective concentration which is
harmless for humans however. The user therefore only needs to
enter said hollow body together with the laundry into the drum.
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The biocidal substance and/or its carrier structure can
especially be chosen in such a way that they remain active
over many washing cycles, e.g. more than one hundred.
The hollow body preferably consists of two half-shells which
are latched onto each other and which non-detachably latched
to each other by the manufacturer after the introduction of
the biocidal substance.
The hollow body can especially consist of a detergent-
resistant plastic.
Preferably, the hollow body comprises an inner shell and an
outer shell. This offers the advantage that the outer shell
can consist of a soft or elastic material which protects the
laundry and which is provided with an arrangement that is
appealing in respect of color and haptics.
In this embodiment, the inner shell can consist of a plastic
that ensures mechanical strength such as a glass-fiber
reinforced polypropylene and the outer shell can consist of
thermoplastic elastomers.
The arrangement, number and cross-section of the openings in
the hollow-body shell have an influence on the concentration
of the biocidal substance in the washing and/or rinsing baths.
Appropriately, the openings in the hollow-body shell can
consist of two sets of mutually opposite holes with diameters
of between 0.5 mm and 5 mm, with these two sets of holes being
appropriately opposite of one another.
An indicator can be embedded in the hollow-body shell in at
least one location, which indicator indicates the end of the
useful life of the apparatus by changing its color. This is
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CA 02680068 2009-09-04
especially useful when the apparatus can be used for a very
large number of laundry batches, e.g. 100, by suitable choice
of the biocidal structure. The period of use can also be
limited in such a case by mechanical wear and tear of the
hollow body.
The hollow body is especially preferably a hollow sphere.
The biocidal substance can consist of nanoscale particles on a
support structure or can be embedded in the same. Suitable
organic or inorganic, porous or water-permeable carrier
materials are known to the person skilled in the art.
Preferably, the biocidal substance comprises metal ions. These
can concern ions of at least one of the metals of Ag, Cu, Zn,
Au, Ir, Pd, Ti, Al and Sn.
Alternatively, the biocidal substance can comprise quaternary
ammonium compounds, triclosan, isothiazoline, antibiotics,
chitosan or mixtures thereof.
According to another embodiment, the biocidal substance can
comprise quaternary ammonium compounds, triclosan,
isothiazoline, antibiotics, chitosan or mixtures thereof.
It is understood that the use of a mixture of different
biocidal substances is also possible. Depending on the choice
made, the average effective concentration is set by the number
and the cross section of the holes, the type of carrier
material, and the quantity of its doping with the biocidal
substance, and alternatively its granulation and quantity. It
can be between 1pg/L and 10 mg/L water for example.
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Principally, all biocidal substances are considered which in
contact with an aqueous medium are released in an effective
concentration which is harmless for human metabolism. Biocidal
substances are especially preferred which are effective not
only during the washing cycle, but also lead to an
impregnation of the laundry, so that the laundry is equipped
in a biocidal manner after the washing for a prolonged period
of time, i.e. the invasion and/or the reproduction of
microorganisms is reduced considerably or even suppressed
completely for some time. This effect was proven especially in
a quantitative respect in the use of metal ions as mentioned
above, especially silver ions.
An embodiment of an apparatus in accordance with the invention
is shown in the drawing, wherein:
Fig. 1 shows an apparatus in the form of a hollow sphere;
Fig. 2 shows a top view of the hollow sphere in Fig. 1;
Fig. 3 shows a sectional view along the line B-B in Fig. 2;
Fig. 4 shows a sectional view along the line D-D in Fig. 2;
Fig. 5 shows the details in Fig. 3 on an enlarged scale.
The hollow sphere shown in Fig. 1 consists of an upper half-
shell 1 and a bottom half-shell 2 which are perforated and
latched together. The outside diameter of the hollow sphere
can be close to 50 mm for example.
Fig. 2 shows a top view of the hollow sphere, mainly for
illustrating the position of the lines of intersection B-B and
D-D in the following drawings.
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Fig. 3 illustrates that a carrier body 3 which is shown here
as a cube by way of example is enclosed in the interior of the
hollow sphere 1.2, which carrier body contains the biocidal
substance. The carrier body 3 can be a fiber structure in the
form of a non-woven material or a multi-layer knitwear or
fabric which is doped with the biocidal substance. Silver-
containing cellulosic fibers with ion-exchanging properties
have proven to be especially good. Support materials to be
considered can also be doped porous polymers, polyurethane,
activated carbon, zeolites, ceramics and the like.
It is possible to omit the support body 3 when the biocidal
substance is a granulated or compact, hardly soluble metal
salt for example.
Figs. 1 and 3 further show that the upper half shell 1 is
provided with a first set of holes 4 and the bottom half shell
2 with a second set of holes 4.
As is shown in Figs. 3 and 4, both half shells are two-layered.
The respective inner shells 1.1, 2.1 consist of glass-fiber
reinforced polypropylene. The outer shells 1.2, 2.2 consist of
a thermoplastic elastomer and are integrally connected with
the respective inner shells 1.1, 2.1 by melting together or in
any other suitable manner.
The holes 4 are provided with a stepped arrangement for
optical reasons, i.e. the cross sections of the holes in the
respective outer shells 1.2, 2.2 are slightly larger than the
cross sections of the corresponding holes in the respective
inner shells 1.1, 2.1. The hole diameter lies in this
embodiment close to slightly more than one millimeter.
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The upper inner shell 1.1 and the bottom inner shell 2.1 are
latched together circumferentially in a virtually non-
detachable way in accordance with Figs. 3 to 5, similarly to a
tongue-and-groove connection. For this purpose, the upper
inner shell 1.1 is provided with numerous webs 1.1.1 which
provide it with a high stiffness, so that the hollow sphere
can only be opened by destroying the same.
One or both half shells can carry an indicator substance which
assumes the place of one hole (each) for example (not shown),
which substance indicates by changing color that depends on
the number, duration and the washing bath temperatures that
the effectiveness of the biocidal substances is coming to an
end.
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Representative Drawing