EP3167107B1 - Washing machine comprising a bleaching device and a reservoir for water-insoluble solid particles - Google Patents

Description

The present invention relates to a washing machine with a decolorizing device and a method for washing textile substrates in such a washing machine.

It is known that colored textiles (textile substrates) can fade during the washing process. Depending on the washing temperature, the washing program selected and the detergent used, one or more dyes can be washed out of the textile substrates to varying degrees. The dissolved dyes pass into the washing liquor, generally a suds, and in this way come into contact with other textile substrates to which the dyes can transfer. This leads to undesired discoloration, especially of light-colored textile substrates, and in the worst case, can completely ruin a piece of clothing, for example.

Numerous different dyes are used in the textile industry today. These dyes vary greatly in terms of their chemical structure, properties, and how they bind to a textile. For example, a distinction can be made between direct dyes, reactive dyes, disperse dyes, acid dyes, vat dyes and others. Different types of fabric, such as cotton, polyamide or polyester, require different types of dyes in order to achieve efficient and long-lasting dyeing of these fabrics. This wide range of dyes used in the textile industry poses a major challenge when looking for efficient measures against discoloration.

Various efforts have already been made to prevent the fading process, particularly in the field of detergent compositions. Dye transfer inhibitors are usually added to today's color detergents, which are intended to prevent the transfer of dyes to other textile substrates. A disadvantage of these additives is that they are usually only effective against individual or a few dyes, but not against a broad spectrum of dyes. For example, commercial dye transfer inhibitors have a good effect on red direct dye, but little or no effect on disperse, acid or vat dyes. However, such a wide range of colors is present in a household colored laundry, since, for reasons of efficiency, sorting by color is generally at best rough (light/dark). is carried out, but not as a rule according to individual shades. In order to achieve adequate effectiveness against such a dye mixture, it would be necessary to include numerous different dye transfer inhibitors in the detergent compositions. However, this would undesirably increase both the complexity of detergent formulations and the cost of the detergent.

From the US5313811A as well as the US3269539A washing machines with deinking devices are known.

From the US-A 3,927,967 a method for treating stains on textile substrates is known, in which the textile substrates are subjected to a treatment with a detergent solution, a photoactivator and oxygen and are irradiated with visible light during this treatment process. However, such a method cannot be used for the treatment of dyed textile substrates, in particular for preventing the dyeing process, since the treatment not only attacks dyes dissolved in the washing liquor, but also dyes bound to the textile substrates and the textile substrates undesirably fade and lose color.

In the WO 2009/067838 A2 describes a method for cleaning laundry with electrolyzed water using oxidative radicals. For this purpose, a water tank is provided in addition to the washing machine. The water contained in the tank is electrolysed by an electrolysis unit, which enriches it with oxidative radicals, which are highly reactive and thus have a cleaning and disinfecting effect, among other things. The water treated in this way is then fed into the actual washing process. The disadvantage here is that the textile substrates to be washed come into contact with the electrolyzed water during the washing process. As a result, not only impurities in the textile substrates, but also the dyes bound to the textile substrates are attacked, which can lead to undesirable fading of the colors.

WO-A-01/71083 discloses a washing machine having a drum for receiving articles to be washed, the drum having at least two rotatable drum sections and a drive, the drum comprising a variety of different drum modes including a mode in which the rotatable drum parts are driven to to cause relative rotation between them. A controller controls the appliance to run a variety of different wash programs, each wash program having an associated drum mode.

WO 2010/094959 A1 relates to the cleaning of substrates using a solventless cleaning system that requires the use of only small amounts of water. In particular, the document deals with the cleaning of textile fibers with the help of such a system, and provides apparatus for use in this regard.

WO-A-2007/128962 enables the efficient separation of the substrate from polymer particles after the cleaning process is complete and describes a design using two internal drums.

The object of the present invention is therefore to provide simple and inexpensive measures by which the risk of discoloration during the washing process in a washing machine is minimized while at the same time protecting the textile substrates to be washed in the presence of water-insoluble solid particles.

1. a. Zeolithe, Tone und/oder Keramik umfassen, und/oder
2. b. Polymerteilchen umfassen und

die Vielzahl von verschmutzten wasserunlöslichen festen Teilchen durch Einleiten, Behandeln unter Einsatz des Aktivierungsmittels und Ausleiten aus der Entfärbungseinrichtung regeneriert werden.The above object is achieved in a first embodiment by a washing machine (1) with a washing chamber (2) for receiving a washing liquor and textile substrates to be cleaned, a reservoir containing a large number of water-insoluble solid particles and a decolorizing device (3) which has an inlet (4) for introducing washing liquor from the washing chamber (2) into the decolorizing device (3) and an outlet (5) for discharging washing liquor from the decolorizing device (3) into the washing chamber (2), and the decolorizing device also has at least one activating agent, which includes a UV_radiation source and is suitable for starting a process for the formation of free radicals in the washing liquor within the decolorizing device (3) and for regenerating the plurality of water-insoluble solid particles, characterized in that the water-insoluble solid particles

1. a. zeolites, clays and/or ceramics, and/or
2. b. Polymer particles include and

the plurality of polluted water-insoluble solid particles are regenerated by being discharged, treated using the activating agent, and discharged from the decolorizing facility.

The washing machine according to the invention can basically be a commercial washing machine, for example a cuboid washing machine with a capacity of about 1 to 20 kg, in particular 4 to 9 kg, of laundry, but also an industrial washing machine with any capacity. Thus, types of washing machines with a different design and a significantly larger capacity also fall within the scope of the invention. The wash chamber is the space through which wash liquor flows during a wash cycle. In a household washing machine, this is generally a washing drum and the space immediately surrounding it.

It has been shown that the dyes that have passed into the washing liquor during a washing process can be decomposed by free radicals. Free radicals have at least one unpaired electron and are therefore extremely reactive and therefore mostly short-lived (usually < 1s). They are able to react with the dyes dissolved in the washing liquor and thus decompose them. An example is the decomposition of the dye Acid Orange 7, which is decomposed by the interaction with free radicals into colorless aromatic by-products, which in turn are converted into aliphatic acids by oxidation.

The washing machine according to the invention makes use of this interaction behavior between free radicals and dyes. For this purpose, it has the decolorizing device into which the washing liquor enriched with dissolved dyes can be introduced from the washing chamber. The activating agent, which is suitable for starting a process for the formation of free radicals in the wash liquor within the decolorizing device, is arranged in the decolorizing device. The free radicals formed attack the dyes in the washing liquor and decompose them. The washing liquor treated in this way is then fed back out of the decolorizing device and into the washing chamber and fed to the further washing process in the washing machine. The proportion of dissolved dyes in the total washing liquor in the washing chamber is thus significantly reduced, thereby minimizing the risk of textile discoloration.

The outstanding effect of the free radicals on a wide variety of dyes is particularly advantageous. As a result, detergent additives that are only effective against individual dyes can be largely dispensed with, and strict sorting of the textile substrates to be washed according to different color shades before washing can also be dispensed with.

The washing machine according to the invention has the advantage that the washing liquor and also the water-soluble solid particles can be treated within the decolorizing device; an undesired influence of the reactive free radicals on the textile substrates located in the washing chamber, generally in a washing drum, and the dyes bound in them is not possible or largely excluded. Both the inlet for introducing the washing liquor from the washing chamber into the decolorizing device and the outlet for guiding the washing liquor out into the washing chamber are designed for this purpose in such a way that textile substrates cannot get into the decolorizing device. For this purpose, the inlet and / or the outlet of the decolorizing device can be equipped, for example, with suitable filters or grids, which are not suitable for textile substrates, but for the wash liquor and the water-insoluble solid particles are passable. The dimensions, in particular the cross-sectional area of the inlet and/or the outlet, can also be dimensioned in such a way that it is not possible for textile substrates to enter the decolorizing device. According to the invention, a control of the inlet and outlet devices can also be provided in order to control them over time and thus convey only the desired components in or out.

The length of the inlet and in particular the outlet of the decolorizing unit is dimensioned in such a way that, taking into account the average flow rate of the washing liquor through the decolorizing device and the average lifespan of the free radicals, it can be assumed that there are practically none in the treated washing liquor when it exits the decolorizing device free radicals are more present.

The wash liquor is generally a wash liquor in which a detergent is dissolved in water. Depending on the requirements, other components can be added to this wash suds. In certain applications, pure water or other suitable liquids can also be used. Constituents of commercially available detergents are well known to those skilled in the art.

In the context of the invention, the activating means comprises a source of UV radiation, i.e. the process of formation of free radicals in the deinking device is initiated by UV radiation. In this embodiment variant, a washing liquor is used as the washing liquor which contains additional chemical components such as hydrogen peroxide (H2O2) or titanium dioxide (TiO2). The UV radiation emitted by the radiation source in the decolorizing device activates the hydrogen peroxide or titanium dioxide contained in the washing liquor and highly reactive hydroxyl radicals (OH radicals) are formed as short-lived products of this reaction, which are able to convert the dyes into to decompose the washing suds. In addition to the hydrogen peroxide and titanium dioxide mentioned, numerous other chemical additives are of course also suitable, which can be activated by UV radiation with the formation of free radicals. The use of hydrogen peroxide is particularly advantageous since it is already contained in numerous detergent compositions as a bleaching agent.

The concentration of hydrogen peroxide in the liquid portion of the wash liquor is preferably 0.1 to 50 mmol/L, particularly preferably 1 to 20 mmol/L. The liquid portion of the wash liquor is understood as the portion of the total wash liquor including the water-insoluble solid particles, which is obtained when the water-insoluble solid particles are separated by centrifuging 8 kg of the wash liquor containing the solid water-insoluble particles for 5 minutes in a centrifuge with horizontal mounted cylindrical rotating body with an inner diameter of 515 mm and an inner depth of 370 mm at 1400 revolutions per minute is separated from the liquid part.

Due to the isolated treatment of the wash liquor in the deinking unit, which is only accessible to the wash liquor and the water-insoluble solid particles, but not to textile substrates, and due to the short lifespan of the free radicals, direct exposure to UV radiation and/or the free Radicals on the textile substrates and any damage to them, such as discoloration, is not possible.

A quartz lamp or a UV light-emitting diode can be used as the UV radiation source. However, other UV radiation sources such as sunlight, gas discharge lamps, fluorescent lamps, LEDs or lasers are also conceivable. Particularly preferred UV radiation sources (6) are a quartz lamp, sunlight, LEDs or a UV light-emitting diode.

It is generally preferred that when a source of UV radiation is present as an activating means, this source is placed in the decolorizing device and/or that the decolorizing device is designed in such a way that the washing chamber is not exposed to direct UV radiation, more preferably no UV Radiation is exposed so that dyes in the textile substrates that may be present in the washing chamber are not damaged. This can be done, for example, by having an aperture or a curve at the entrance and exit in the direction of the washing chamber, and the washing liquor has to flow around the aperture or around the curve. For example, the inputs and outputs of the decolorizing device can also be arranged in one direction so that they do not point in the direction of the washing chamber.

The preferred wavelength range of the emitted UV radiation is between 100 and 400 nm, particularly preferably between 250 and 400 nm. Initial tests indicate that there is a dependency between the wavelength of the emitted radiation and the type of decomposable dye. In addition to irradiating a continuum, it is of course also possible to set UV radiation discontinuously and with one or more discrete wavelengths.

According to a further embodiment of the washing machine according to the invention, at least one additional pump is provided in addition to the pump usually present in a washing machine, which pumps the washing liquor from the washing chamber into and/or out of the decolorizing device. This allows the decolorization process to be made even more efficient.

The onset, intensity and duration of the free radical formation process in the deinking means are preferably controllable. The onset of the process can thus be linked to the achievement of specific operating parameters, for example to a specific temperature of the wash liquor or to a specific phase of the wash cycle. For example, a temperature sensor can be provided for temperature-dependent regulation, by means of which the temperature of the washing liquor can be detected. A purely time-based regulation can also be provided, in which the process starts at a presettable point in time. The duration of the process can also be set so that it stops as soon as the wash liquor drops below a certain level of dyes. In the case of washing cycles at a particularly low temperature, in which there is no risk of dyes being washed out into the washing liquor, the onset of the process can also be completely prevented. On the other hand, at high washing temperatures and when washing particularly strong staining textile substrates, the intensity and duration of the process can be increased accordingly.

The temperature of the wash liquor at which the washing machine according to the invention can be operated can be between 10 and 100.degree. C., preferably between 20 and 60.degree.

According to one embodiment of the invention, the decolorizing device can be permanently installed in a housing of the washing machine. In this case, the voltage supply for the activation means and, if necessary, for the pump can be coupled to the voltage supply of the washing machine. The decolorizing device can be mounted, for example, under the drum or on the inside of the door of the washing machine. Corresponding lines which can be connected to the inlet or the outlet of the decolorizing device can be provided in the washing machine for feeding the washing liquor into the decolorizing device and out of it again. For example, the washing chamber can have a washing liquor outlet which can be connected to the inlet of the decolorizing device. Correspondingly, the outlet of the decolorizing device can be connectable to a washing liquor inlet of the washing chamber, so that the treated washing liquor can be returned from the decolorizing device back into the washing chamber. In a further embodiment, however, the decolorizing device can also be integrated into the pumping circuit that is usually present.

Alternatively, the decolorizing device can also be designed as a separate, preferably battery-operated module. This can, for example, be attached to the inside of the washing machine door using a suitable bracket. The advantage of a module that can be brought in separately is that it can only be used when required and is therefore subject to less wear and tear. In addition, a separate module can also be added later installed in an existing washing machine or taken from a defective washing machine and installed in a new washing machine.

A special property of UV radiation is that it also has a germ-killing effect in a wavelength range of 200 and 300 nm. As a result, microorganisms such as bacteria, viruses and protozoa can be deactivated. This ability has made UV radiation widely used as an environmentally friendly, chemical-free, and highly effective method of disinfecting water. It is also used to protect the water from harmful microorganisms.

In contrast to chemical water disinfection methods, UV irradiation is based on a physical process in which microorganisms are deactivated quickly and effectively. When bacteria, viruses and protozoa are exposed to the germicidal wavelengths of UV radiation, they lose their ability to reproduce and infect.

UV radiation has proven to be highly effective against pathogenic organisms, including those that cause cholera, polio, typhoid, hepatitis and other bacterial, viral and parasitic diseases. Therefore, according to the invention, the UV radiation (alone or in conjunction with hydrogen peroxide) is used for UV oxidation, a process in which the number of microorganisms on the textile substrates and / or the water-insoluble solid particles and / or in the liquid phase of the Wash liquor is significantly reduced.

Photocatalytic water splitting is also possible according to the invention by using short-wave UV radiation in the range from 250 to 300 nm with the use of suitable photocatalysts. These are either added to the detergent or the water-insoluble solid particles, or can consist partly or entirely of them. It is also possible to introduce these in a stationary manner in the decolorizing device. In principle, it is therefore possible to dispense with the use of amounts of hydrogen peroxide from the detergent or components that generate hydrogen peroxide.

The invention thus also discloses a module that can be used in a washing machine, which has a decolorizing device with an inlet for introducing washing liquor into the decolorizing device and an outlet for guiding washing liquor out of the decolorizing device, and which has at least one activating agent that is suitable within the Decolorizing device to start a process for the formation of free radicals in the washing liquor.

The essential feature of the washing machine according to the invention is the presence of the decolorizing device integrated into the above device, the above water-insoluble solid particles and a reservoir for the particles.

The washing machine of the present invention typically includes a hinged door in a cabinet to allow access to the interior of the wash tub to provide a substantially closed system. Preferably, the door opens a window of the stationary cylindrical drum which is rotatably supported in another drum, while the rotatably supported cylindrical drum is mounted vertically within the housing. Consequently, a front loader is preferred. Alternatively, the stationary cylindrical drum may be mounted vertically within the housing and the access means located in the top of the device.

The washing machine is suitable to provide contact of the particles with the soiled substrate. Ideally, these particles should be efficiently circulated to promote effective cleaning.

• Einfüllen der zu waschenden textilen Substrate in die Waschkammer der Waschmaschine;
• Starten eines Waschganges;
• Waschen der Wäsche durch Inkontaktbringen der textilen Substrate mit Wasser, einem Waschmittel und einer Vielzahl von wasserunlöslichen festen Teilchen;
• Einleiten von Waschflotte aus der Waschkammer in die Entfärbungseinrichtung;
• Behandlung der Waschflotte in der Entfärbungseinrichtung unter Einsatz des Aktivierungsmittels;
• Ausleiten von behandelter Waschflotte aus der Entfärbungseinrichtung in die Waschkammer,
  wobei das Einleiten und/oder Ausleiten der Waschflotte sowie das Behandeln der Waschflotte in der Entfärbungseinrichtung kontinuierlich, diskontinuierlich oder sequentiell durchgeführt wird.

According to the invention, the washing machine comprises at least one reservoir, in particular with a corresponding controller, containing the water-insoluble solid particles, which is located, for example, inside the washing machine and is suitable for controlling the flow of particles inside the washing machine and containing the particles for regeneration. In a further embodiment, the invention also relates to a method for washing textile substrates in a washing machine using one of the washing machines defined above, comprising the steps:

• Loading the textile substrates to be washed into the washing chamber of the washing machine;
• starting a wash cycle;
• washing the laundry by contacting the textile substrates with water, a detergent and a plurality of water-insoluble solid particles;
• Introducing washing liquor from the washing chamber into the decolorizing device;
• Treatment of the washing liquor in the decolorizing device using the activating agent;
• discharge of treated washing liquor from the decolorizing device into the washing chamber,
  the introduction and/or discharge of the washing liquor and the treatment of the washing liquor in the decolorizing device being carried out continuously, discontinuously or sequentially.

Figur 1:

ein Ausführungsbeispiel der erfindungsgemäßen Entfärbungseinrichtung in schematischer Darstellung;

Figur 2:

schematische Ansicht einer Waschmaschine mit der Entfärbungseinrichtung aus Figur 1 gemäß der Erfindung;

The invention is explained in more detail below using exemplary embodiments and with reference to the accompanying drawings. Show it:

Figure 1:

an embodiment of the decolorizing device according to the invention in a schematic representation;

Figure 2:

schematic view of a washing machine with the decolorizing device figure 1 according to the invention;

Based on figure 1 the mode of operation of the decolorizing device is first explained in more detail.

figure 1 shows an exemplary embodiment of a decolorizing device according to the invention, designated as a whole by 3, which is suitable for receiving washing liquor. For this purpose, the decolorizing device 3 has an inlet 4 and an outlet 5 . Through the inlet 4, washing liquor (not shown) can reach the interior of the decolorizing device from the area surrounding it. The wash liquor can exit the decolorizing device 3 again via the outlet 5 . The direction of flow of the wash liquor is indicated schematically by arrows.

A UV radiation source 6 is arranged inside the decolorizing device 3 . The arrangement of the UV radiation source 6 within the decolorizing device 3 is in figure 1 shown only schematically; in particular, the electrical connections of the UV radiation source 6 were not shown. The UV radiation source 6 can preferably be a UV quartz lamp which emits UV radiation with a wavelength of 254 nm.

If a washing liquor containing hydrogen peroxide (H2Oz), in which dyes are dissolved, is introduced through the inlet 4 into the decolouration device 3, H2O2 molecules are activated by the UV radiation emitted by the quartz lamp and short-lived, highly reactive ones are formed Hydroxyl radicals (OH). These OH radicals attack the dyes dissolved in the washing liquor and decompose them. The washing liquor decolorized in this way is finally conducted out of the decolorizing device 3 again through the outlet 5 .

According to the invention, the term “decolorized washing liquor” is intended to mean that the dye content of the washing liquor when it leaves the decolorizing device 3 is significantly lower than when it enters the decolorizing device 3. The absolute degree of decolorization depends on different factors Parameters such as the original dye content in the wash liquor, residence time of the wash liquor in the decolorizing device 3, radiation intensity of the UV lamp and others.

In the figure 2 The washing machine 1 shown in a simplified form has a drum 13 which is part of a washing chamber 2 and below the decolorizing device 3 containing a UV quartz lamp according to FIG figure 1 is arranged. The washing chamber 2 consists of the washing drum 13 and the space immediately surrounding it, through which the washing liquor flows during the wash cycle. The flow of liquid through the decolorizing device 3 is indicated by arrows. It is just as possible to arrange the decolorizing device 3 in the alternative embodiment with the electrode arrangement 7 in an area below the drum 13 . In the example shown, the decolorizing device 3 is an integral part of the washing machine 1.

The washing machine 1 according to the invention, which has a decolorizing device 3, and the method operated with this for washing textile substrates thus represent measures with the help of which the risk of discoloration during the washing process in a washing machine can be minimized. In particular, the invention is characterized in that a wide variety of dyes can be decomposed simultaneously in a simple manner without the textile substrates themselves being affected by the color neutralization process. As a result of this reduced risk of discoloration, the pre-sorting of textile substrates according to color before washing can be largely dispensed with, which means a significant time saving.

Another aspect of the present invention comprises a method of cleaning a soiled textile substrate, which method includes treating the wet textile substrate with a formulation comprising a plurality of water-insoluble solid particles, wherein the particles are optionally after regeneration with or without Use of a detergent can be reused in further cleaning processes according to the method.

According to the invention, the water-insoluble solid particles are exposed to UV radiation for regeneration in the deinking device during the washing process or in a separate step.

The substrate includes textile substrates, each optionally made from a variety of materials, which can be either a natural fiber such as cotton or synthetic textile fibers such as nylon 6,6 or a polyester.

1. a. Zeolithen, Tonen und/oder Keramikund/oder
2. b. Polymerteilchen.

The water-insoluble solid particles can be inorganic and/or organic in nature and are selected from

1. a. zeolites, clays and/or ceramics and/or
2. b. polymer particles.

The particles can have a certain degree of hydrophilicity in order to enable them to be wetted with the wash liquor.

The organic water-insoluble solid particles can comprise any of a variety of different polymers. Polyalkenes such as polyethylene and polypropylene, polyesters and polyurethanes are particularly preferred. Preferred, however, are the polymeric particles of polyamide, more particularly particles of nylon, most preferably in the form of nylon chips. The polyamides are particularly effective for aqueous stain/soil removal, while polyalkenes are particularly useful for oily stain removal. Optionally, copolymers of the above polymeric materials can be used for the purposes of the invention.

Various nylon homo- or co-polymers can be used including nylon 6 and nylon 6,6. Preferably, the polyamide comprises nylon 6,6 homopolymer having an average molecular weight ranging from 5,000 to 30,000 daltons, preferably from 10,000 to 20,000 daltons, most preferably from 15,000 to 16,000 daltons.

The mean molar masses given here and later, where appropriate, for other polymeric ingredients are weight-average molar masses M _w , which can in principle be determined by means of gel permeation chromatography using an RI detector, with the measurement advantageously being carried out against an external standard.

The water-insoluble solid particles or granules, particles or moldings are of such a shape and size that enables good flowability and close contact with the textile substrate. Preferred particle shapes include spheres and cubes, but the preferred particle shape is cylindrical. The particles are preferably sized so that they each have an average weight in the range 20-50 mg, preferably 30-40 mg. In the case of the most preferred cylindrical shaped particles, the preferred average particle diameter is 1.5 to 6.0 mm, more preferably 2.0 to 5.0 mm, most preferably 2.5 to 4.5 mm, while the length of the cylindrical particles is preferably in the range 2.0 to 6.0 mm, more preferably 3.0 to 5.0 mm and most preferably in the range 4.0 mm.

Before cleaning, the textile substrate is preferably moistened by wetting with water in order to provide an additional improvement for the wash liquor and thereby enable an improvement in the transport properties within the system (pretreatment). Thus, more efficient transfer from the detergent to the substrate and removal of soils and stains from the substrate is facilitated. Most conveniently, the substrate can be wetted by contact with tap water. Preferably, the wetting treatment is carried out to achieve a substrate to water weight ratio of from 1:0.1 to 1:5; more preferably the ratio is between 1:0.2 and 1:2, with particularly favorable results being obtained with ratios such as 1:0.2, 1:1 and 1:2. However, in some cases successful results can be achieved with substrate to water ratios of up to 1:50, although such ratios are not preferred in view of the significant amounts of effluent that are generated.

In the process according to this aspect of the invention, which can be regarded as an interstitial process between cleaning and scouring, a weight ratio of textile substrate to water-insoluble solid particles is in the range from 1:1 to 1:30, in particular from 1:1.5 to 1:2.5, especially adjusted from 1:2. The proportion of water-insoluble solid particles is determined as the weight of the particles in the dry state, i.e. after storage for 24 hours at 21° C. and a relative atmospheric humidity of 65%.

Furthermore, it has been found that regeneration of the water-insoluble solid particles is possible and the particles are satisfactorily reused in the purification process, although some degradation in performance is generally observed after three uses of the particles. When the particles are reused, best results are obtained if they are recoated with the detergent before reuse.

The water-insoluble solid particles can be regenerated in a manner known per se, as described, for example, in WO 2012/035342 A1 is described. In the context of the present invention, regeneration takes place by introducing the particles, optionally with commercial chemicals and/or the detergent, into the decolorizing device, for example in a separate rinsing cycle, optionally by adding other cleaning agents, which can also be aggressive in nature. The temperature of the regeneration step is independent of the washing temperature if the textile substrate was removed from the washing machine before regeneration. The customary detergent raw materials can also be used.

A further subject relates to the use of a detergent containing a precursor of free radicals, in particular H ₂ O ₂ , in a method according to any one of claims 7 to 12 for washing textile substrates using a large number of water-insoluble solid particles.

Claims (13)

1. A washing machine (1) comprising a washing chamber (2) for receiving a washing liquor and textile substrates to be cleaned, a reservoir () containing a plurality of water-insoluble solid particles, and a decolorizing device (3) having an inlet (4) for introducing washing liquor from the washing chamber (2) into the decolorizing device (3) and an outlet (5) for discharging washing liquor from the decolorizing device (3) into the washing chamber (2), and the decolorizing device further comprises at least one activating agent comprising a source of UV radiation and adapted to initiate within the decolorizing device (3) a process for the formation of free radicals in the wash liquor as well as to regenerate the plurality of water-insoluble solid particles, characterized in that

   the water-insoluble solid particles

   a. comprise zeolites, clays and/or ceramics, and/or

   b. comprise polymer particles and

   the plurality of contaminated water-insoluble solid particles are regenerated by introduction, treatment using the activating agent and discharge from the decolorizing device.
2. Washing machine (1) according to claim 1 , characterized in that the decolorizing device contains a photocatalyst for photocatalytic water splitting.
3. Washing machine according to one of the claims 1 to 2, characterized in that at least one pump is provided which pumps the wash liquor from the washing chamber (2) into and/or out of the decolorizing device (3).
4. Washing machine (1) according to any one of claims 1 to 3 , characterized by a control unit for regulating the onset and/or intensity and/or duration of the free radical formation process.
5. Washing machine (1) according to claim 4 , characterized by a temperature sensor for detecting the temperature of the wash liquor.
6. Washing machine (1) according to any one of claims 1 to 5 , characterized in that the decolorizing device (3) is located in a housing inside or outside the washing machine (1).
7. Method for washing textile substrates using a washing machine (1) according to any one of claims 1 to 6 , comprising the steps:

   - Loading the textile substrates to be washed into the washing chamber (2) of the washing machine (1);

   - Starting a wash cycle;

   - Washing of laundry by bringing textile substrates into contact with water, a detergent and a variety of water-insoluble solid particles;

   - Introduction of wash liquor from the wash chamber (2) into the decolorizing device (3);

   - Treatment of the wash liquor in the decolorizing device using the activating agent, wherein the plurality of contaminated water-insoluble solid particles are regenerated in the decolorizing device.

   - discharging treated wash liquor from the decolorizing device (3) into the washing chamber (2), the introduction and/or discharge of the wash liquor and the treatment of the wash liquor in the decolorizing device being carried out continuously, discontinuously or sequentially .
8. Process according to claim 7 , characterized in that the wash liquor is adjusted to a temperature of from 10 to 100 °C, preferably from 20 to 60 °C.
9. Process according to claim 7 or 8 , characterized in that the weight ratio of textile substrate to water-insoluble solid particles is in the range from 1:1 to 1:30, in particular from 1:1.5 to 1:2.5, very particularly 1:2.
10. A process according to any one of claims 7 to 9, characterized in that the water-insoluble solid particles comprise, solid polymer particles, wherein the solid polymer particles comprise polyalkanes, polyesters, polyurethanes and/or polyamides including copolymers thereof, in particular a nylon 6.6 homopolymer having an average molecular weight of 5,000 to 30,000 daltons.
11. The method of any one of claims 7 to 10, characterized in that the particles each have an average weight in the range of 20 to 50 mg.
12. A process according to any one of claims 7 to 11, characterized in that the plurality of contaminated water-insoluble solid particles are regenerated using further additives by introduction, treatment using the activating agent and discharge from the decolorizing device.
13. Use of a detergent comprising a precursor of free radicals, in particular H₂O₂, in a process according to any one of claims 7 to 12 for washing textile substrates using a plurality of water-insoluble solid particles.

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