CN110241555B

CN110241555B - Method for treating laundry in washing machine and washing machine adapted thereto

Info

Publication number: CN110241555B
Application number: CN201910175456.4A
Authority: CN
Inventors: G·奇热夫斯基
Original assignee: BSH Hausgeraete GmbH
Current assignee: BSH Hausgeraete GmbH
Priority date: 2018-03-09
Filing date: 2019-03-08
Publication date: 2023-02-17
Anticipated expiration: 2039-03-08
Also published as: DE102018203577A1; CN110241555A; EP3536844A1; EP3536844B1; PL3536844T3

Abstract

The invention relates to a method for treating laundry (4) in a washing machine (1) having a lye container (2), a drum (3) which is mounted rotatably about a substantially horizontal axis in the lye container (2) for receiving the laundry (4) and a control device (7), wherein the method comprises the following steps: (a) Placing an open or closed container (8) containing a laundry treatment agent into the drum (3); (b) The aqueous liquid (6) is introduced into the lye container (2) in an amount W which is sufficient for the liquid level h in the drum (3) to have a predetermined minimum value h _min (ii) a (c) At a predetermined time t _set The aqueous liquid (6) is moved during > 1 minute, the drum (3) being in a stationary state or being moved such that no rotation of the drum (3) by an angle α ≧ 180 ° occurs. The invention also relates to a washing machine suitable for implementing said method.

Description

Method for treating laundry in washing machine and washing machine adapted thereto

Technical Field

The invention relates to a method for treating laundry in a washing machine and to a washing machine for carrying out the method.

Background

In the treatment of laundry in washing machines, chemical laundry treatment agents (hereinafter sometimes also abbreviated to "treatment agents") are generally used, which can be combined differently depending on the purpose of use or desired action. Laundry treatment agents or treatments, such as detergents or softeners, usually comprise a plurality of ingredients which have different functions when treating, for example washing, the laundry in a washing machine. Currently, laundry treatment agents are used in liquid or powder form in the way they accomplish mixing. However, particularly functional inclusions can interact with one another, so that it makes sense to separate them to some extent before they come into contact with the laundry.

Recently, so-called detergent pads have been increasingly used. The detergent pad has at least one chamber surrounded by a water-soluble film, wherein the detergent pad contains at least one liquid or powder-like laundry treatment agent in the chamber or chambers. The detergent pad enables simpler dosing of the treatment agent at a generally increased price and furthermore enables the separation of the contents which may not be very compatible. Thus, the detergent pad has, for example, three chambers. Here, the content material is retained until the washing procedure is carried out. The film dissolves on contact with water in order to release the active substance.

However, the film sometimes does not dissolve very quickly. On the one hand, film residues are present even at the end of the washing phase. Furthermore, the detergent pad sometimes slides into the door rubber ring, i.e. the ring of the drum, and sometimes comes into contact again with water during the rinsing phase. This can lead, in a very unfavorable case, to the viscous residues also appearing in the laundry at the end of the rinsing phase.

Disclosure of Invention

Against this background, the object of the present invention is to provide an improved method for treating laundry in a washing machine, which is suitable, in particular, in the case of detergent pads. Furthermore, the invention proposes a washing machine suitable for implementing the method.

The object of the invention is achieved by a method for treating laundry and a washing machine suitable for use in said method according to the independent claims. Preferred embodiments of the invention are specified in the corresponding dependent claims. Preferred embodiments of the method correspond to preferred embodiments of the washing machine, also when not mentioned here in particular.

The invention therefore relates to a method for treating laundry in a washing machine having a lye container, a drum which is mounted rotatably about a substantially horizontal axis in the lye container for receiving the laundry, and a control device, wherein the method comprises the following steps:

(a) Placing an open or closed container containing a laundry treatment agent into a drum;

(b) The aqueous liquid is injected into the lye container in an amount W which is sufficient for the liquid level in the drum to have a predetermined minimum value h _min ；

(c) At a predetermined time t _set The aqueous liquid is moved during > 1 minute, the drum being in a stationary state or being moved such that no rotation of the drum at an angle alpha ≧ 180 ° occurs.

By "substantially horizontal" is meant herein that there may typically be a deviation from the horizontal of at most 25%, preferably at most 15%.

Although the aqueous liquid according to the present invention is not limited. However, since the aqueous liquid is intended in the context of the present invention for treating, in particular washing, the laundry, the aqueous liquid is water which is as clean as possible. It is therefore particularly preferred to use water from the water supply of the washing machine, i.e. tap water. However, the aqueous liquid may also be, for example, the rinse liquid from the last rinsing process stored in the washing machine.

Method step (c) advantageously achieves that substantially no redistribution of the laundry and the container inside the drum takes place. This allows the container to be held inside the drum in a position in which it can be repeatedly flushed from all sides with the aqueous liquid. The friction on the container, which promotes rapid dissolution of the container, is additionally generated by moving the aqueous liquid or by flushing from four sides.

Preferably, the predetermined period t _set In the range of 1.5 to 5 minutes. Time period t _set The time period is selected such that it is sufficient for the container containing the laundry treatment agent to substantially dissolve and dispense the laundry treatment agent in the aqueous liquid. This advantageously achieves an early and substantially complete supply of the laundry treatment agent to the washing process. Furthermore, it is avoided that residues of the laundry treatment agent, which were not dissolved before in the washing phase, occur in the rinsing phase.

In a preferred embodiment of the method according to the invention, the washing machine has a circulation pumping line and a pump for delivering the aqueous liquid, and the aqueous liquid is moved in step (c) by circulating pumping through the circulation pumping line. The circulation pumping is usually effected here by means of a suitable pump. For this purpose, the pump for delivering the aqueous liquid, which is contained in the washing machine used according to the invention, can also be considered. The already dissolved laundry treatment agent is thus advantageously distributed in the aqueous liquid by the circulation pumping system. Furthermore, the movement of the aqueous liquid in the region of the detergent pad is also achieved by means of circulation pumping. The effect thus contributes to a rapid dissolution of the container or detergent pad containing the laundry treatment agent.

Preferably, the predetermined minimum value h in step (b) _min The choice is made such that at least the drum is in contact with the aqueous liquid or the circulating pumping is effected by means of a circulating pumping system, wherein the circulating pumping requires that so much aqueous liquid is contained in the circulating pumping system that it is sufficient for the liquid pumped out of the lye container to be conducted back into the lye container through the circulating pumping line. At the liquid level thus selected, it is advantageously ensured that the movement of the drum carrying the liquid or the operation of the circulating pumping system effects a movement of the aqueous liquid.

In particular, the containers placed on the lower region of the drum in step (a) are brought into contact early at a level which is predetermined in this way. Preferably, the minimum value h of the liquid level _min This is chosen so that the liquid level is higher than the lower container in the drum.

In an alternative or additional embodiment of the method according to the invention, in step (c), the drum 3 is set to a predetermined amplitude a _T The inversion is carried out with an amplitude of less than 180 °, preferably less than 150 °, more preferably less than 120 ° and in particular in the range from 70 ° to 110 °, wherein the amplitude a _T Is the maximum deflection of the drum during the reversal step in degrees ("°"). It is also preferred here that in step (c) the drum is moved at a speed corresponding to a drum speed in the range of 25 to 35 revolutions per minute. The speed should preferably be less than or equal to 50 revolutions per minute. Preferably, the maximum deflection of the drum is related to the selected speed of the drum, wherein for small amplitudes a _T The speed of the drum can be chosen to be low and for large amplitudes A _T A high speed of the drum can be selected. This has the advantage that the control time for the drive motor does not become too short or the drive motor does not have to provide an excessively large drive torque in order to achieve the rotational acceleration that is otherwise required for the drum.

A further method according to the invention is preferred wherein in step (b) the drum is stopped during the injection of the aqueous liquid.

Furthermore, a method is preferred in which the water quantity W is selected as a function of the load L of the laundry, wherein the relationship between W and L is stored in the control device.

Finally, a method is preferred, wherein in step (c) the degree of movement is selected as a function of the load L of the laundry, wherein a relationship between the degree of movement and L is stored in the control device.

Here, the load L of the laundry is determined by weighing the drum, for example. It is also possible to determine the loading L as a function of the absorption properties of the laundry in the wetting phase. In this method, in particular, the hydrostatic pressure of the aqueous liquid in the lye container is measured by using a pressure sensor, which hydrostatic pressure is a measure of the aqueous liquid present in the lye container as "free bleaching liquor". When a relatively large amount of laundry absorbs a relatively large part of the aqueous liquid, the amount of bleaching liquor is less in the case of the same amount of water being added to the lye container. From this relationship, the amount of washing liquid can be determined, wherein the type of the washing can be taken into account. This can be done, if necessary, by a user input of the washing machine or by other means, for example by means of infrared spectroscopy, to determine the type of laundry.

However, it is conceivable here that the method according to the invention generally overlaps the wetting phase, so that the loading L is generally not already taken into account at the beginning, but only during the implementation of the method according to the invention.

In a particularly preferred embodiment of the method according to the invention, the degree of movement in step (c) comprises the amplitude a _T The drum is reversed by said amplitude, wherein said amplitude A _T Is the maximum deflection of the cylinder during the reversal step in degrees.

It is generally applicable that the maximum permissible extent of the movement in step (c) can be greater for larger loads of laundry.

In a preferred embodiment of the method according to the invention, wherein the washing machine has a circulation pumping line, the degree of movement of the aqueous liquid in step (c) comprises the circulation pumping speed of the aqueous liquid in the circulation pumping line. This has the advantage, in particular, that when the drum is stopped, a movement of the liquid is also caused, or when a movement of the aqueous liquid is caused by a movement of the drum, said movement is further intensified. Thus, the container containing the laundry treatment agent can be dissolved more quickly.

The open or closed container used in step (a) of the method according to the invention generally has the function of dispensing the treating agent contained in the container in the aqueous liquid. The container is not restricted if said function is fulfilled, so that the concept "container" includes a form-stable container as well as a detergent pad. The dimensionally stable container is here an open cup in the sense of the present invention, the wall of which is usually made of a suitable plastic that is sufficiently thick to be insoluble in aqueous liquids, in order to achieve dimensional stability.

In a highly preferred embodiment of the method according to the invention, the container is a detergent pad which has at least one cavity which is surrounded by a water-soluble film, wherein the detergent pad contains at least one liquid or powdered detergent treatment agent in the cavity or cavities. The water-soluble film is made of, for example, polyvinyl alcohol or a derivative thereof.

It is preferred according to the invention that the washing machine used in the method comprises a treatment agent sensor for determining the concentration of the laundry treatment agent, and in the method the dispensing of the laundry treatment agent from the container in the aqueous liquid is monitored by means of the treatment agent sensor in order to determine a predetermined dispensing of the laundry treatment agent in the aqueous liquid. The "predetermined dispensing" can here be selected such that the entire laundry treatment agent from the container is dispensed. In the case of a laundry mat, this means in particular that the water-soluble film dissolves to some extent or completely, so that the laundry treatment agent contained in the cavity or cavities of the laundry mat can completely reach the aqueous liquid. The treating agent sensor according to the present invention is not limited if the treating agent sensor fulfills the function. Here, the treatment agent sensor may be an electromechanical sensor or an optical sensor, since a plurality of laundry treatment agents are dyed.

According to the invention, it is preferred that in step (b) the aqueous liquid is injected through the rim of the washing machine, i.e. the aqueous liquid is delivered directly to the laundry. That is, the liquid may be directed through a water flow path that connects with the collar and is preferably not directed through into the shell. Alternatively, the water flow path may also be guided through a pre-wash chamber that is flushed into the housing. In this way, in the event of incorrect use when using the detergent pad, i.e. when the detergent pad is not placed under the laundry but between or on the laundry, it is also possible for the aqueous liquid to reach the detergent pad located there and release the laundry treatment agent after the film has dissolved.

The method according to the invention may be specifically selected by a user of the washing machine through an operating unit of the washing machine. This advantageously enables the user to select a washing program suitable for the laundry treatment agent. Alternatively, the method according to the invention is integrated into a washing program which is particularly suitable in the case of use of a detergent pad.

Furthermore, the subject matter of the invention is a washing machine having a lye container, a drum which is mounted rotatably in the lye container about a substantially horizontal axis for receiving laundry, and a control device, wherein the washing machine, in particular the control device of the washing machine, is provided for carrying out a method for treating laundry, comprising the following steps:

(b) The aqueous liquid is injected into the lye container in an amount W which is sufficient for the liquid level h in the drum to have a predetermined minimum value h _min ；

The washing machine may be a washing machine itself or a washer-dryer, i.e. an appliance also having a drying device.

In a preferred embodiment, the washing machine has a pump for delivering the aqueous liquid and a circulation pumping line. The circulation pumping line is typically a component of a circulation pumping system, which also has a circulation pump. The circulation pump may be a pump which is also used for pumping out and thereby cleaning the washing lye. In this case, the operation of the pump is suitably controlled, for example by means of a three-way valve, so that it is possible to choose between circulating pumping and pumping. However, in this embodiment of the washing machine according to the invention, two pumps can also be present, one of which is used only in the circulation pumping system and the other pump is used only for pumping out used washing lye or rinsing liquid.

The circulation pumping system provided in this embodiment of the invention is designed such that the aqueous liquid present in the lye container is in contact with the laundry in the drum in the circulation system. In the methods described herein, a recirculating pumping system is used to substantially distribute the laundry treatment agent in the aqueous liquid, for example, in a manner that supports dissolution of the detergent pad. However, circulation pumping systems are also advantageously used in washing phases in which an aqueous liquid, which usually contains a detergent, is brought into contact repeatedly with the items of laundry to be cleaned.

The washing machine used here usually also has a heating device and a lye discharge system with a lye pump, which is arranged on the bottom of the lye container. Furthermore, the washing machines used here usually also have laundry drivers and/or drains.

In a preferred embodiment of the laundry washing machine according to the invention, a temperature sensor is arranged in the lye container. The temperature sensor is then arranged in a lower region of the lye container, preferably in what is referred to as a heating body recess of the lye container housing, in which heating device usually also is arranged.

The invention has the advantage of facilitating the dispensing of the laundry treatment agent in an aqueous solution, which may also be referred to as wash liquor, without the container containing the laundry treatment agent being moved excessively and, for example, becoming caught in the rim of a washing machine. This is important in particular in the case of detergent pads. In this case, it is also helpful to dissolve the detergent pad, so that residues of film residues in the cleaned laundry can be completely avoided by completely dissolving the detergent pad quickly.

Drawings

Further details of the invention result from the following description of one non-limiting embodiment of a laundry washing machine according to the invention, in which a method according to the invention can be implemented. Reference is made herein to fig. 1.

Fig. 1 shows in particular a schematic view of the main parts of the invention of a washing machine suitable for implementing the method according to the invention.

Detailed Description

The washing machine 1 shown schematically comprises a drum 3 with laundry 4 rotatably supported in a lye container 2 about a horizontal axis of rotation 18. The washing machine 1 also has a fresh water supply which is formed by a valve 23 which can be controlled by the control device 7 and a fresh water supply line 21. The fresh-water feed line 21 passes through the metering device 22 for the laundry treatment agent, i.e. the rinsing housing 22, so that, in addition to the addition of the laundry treatment agent provided according to the invention, the laundry treatment agent can also be rinsed from the metering device 22 into the lye container 2 by means of the fresh-water feed device via the fresh-water feed line 21. In the method according to the invention, however, it is provided that the aqueous liquid, typically water, reaches the drum 3 without prior contact with the laundry treatment agent by flushing into the housing 22 or a collar, not shown here, of the washing machine 1.

The drum 3 can be driven by a drive motor 11. The drive motor 11 is in this non-limiting embodiment a brushless and thus noiseless drive motor 11.

The washing machine 1 also has a

circulation pumping system

5,9, 14 consisting of a circulation pumping line 9, a lye container inlet 14 and a pump 5, which can also be referred to as lye pump 5. An aqueous liquid 6, for example water, can be passed through the lye by means of a circulating

pumping system

5,9, 14The pump 5 is pumped out of the lye container 2 via the lye container outlet 10 and is conducted back into the lye container 2 again via the circulating pump line 9 and the lye container inlet 14. The circulation of the aqueous liquid 6 is effected in the manner described. In this case, in particular, step (c) of the method according to the invention can be carried out, i.e. over a predefined period t _set The aqueous liquid 6 is moved during > 1 minute, the drum 3 being in a stationary state or being moved such that no rotation of the drum 3 at an angle alpha ≧ 180 ° occurs.

In the exemplary embodiment shown here, the lye pump 5 is furthermore connected to a drain line 13. A three-way valve, which can be controlled by the control device 7 and is not shown here, in this embodiment effects a switching of the pump operation from the

recirculating pumping system

5,9, 14 to the drain line 13. In this way, the aqueous liquid from the lye container 2 can be pumped out and removed on demand. However, it is also possible to use two pumps, so that a single pump is used for the circulation pumping and for the pumping-out.

The heating device 15, the pressure sensor 16 and the temperature sensor 17 are located in a so-called heating body recess 20 arranged in the lye container 2.

The pressure sensor 16 is a sensor for measuring the hydrostatic pressure in the lye container 2. The hydrostatic pressure p is derived from the level h of the aqueous liquid 6 in the lye container 2 and in this case in particular in the heating body recess 20. The pressure sensor 16 can be used according to the invention, in particular, for setting a predefined filling level h _min . Furthermore, the pressure sensor is also used as described here to determine the load L of the drum 3 with laundry 4.

Not shown is a scale for determining the amount of laundry added, however, also in the washing and rinsing phases, which scale alternatively enables a better design of the method according to the invention.

The exemplary washing machine 1 shown in fig. 1 implements a method for treating laundry 4, wherein the following steps are carried out:

(a) Placing an open or closed container 8 containing a laundry treatment agent into the drum 3;

(b) The aqueous liquid 6 is introduced into the lye container 2 in an amount W sufficient for the liquid level h in the drum 3 to have a predetermined minimum value h _min ；

(c) At a predetermined time t _set The aqueous liquid 6 is moved during > 1 minute, the drum 3 being in a stationary state or being moved such that no rotation of the drum 3 at an angle alpha ≧ 180 ° occurs.

In the embodiment shown here, the closed container 8 is in particular a detergent pad which has at least one chamber surrounded by a water-soluble film, wherein the detergent pad contains at least one liquid or powdered detergent treatment agent in the chamber or chambers. Preferably, the container 8 and then the laundry 4 are put into the drum 3 by the user first. The container 8 is thus located on the lower region of the drum 3, said container being first in contact with the aqueous liquid 6 entering the lye container 2. The level of the aqueous liquid 6 is shown in fig. 1 by the horizontal line shown inside the drum, wherein the level h is higher than the container 8. The movement of the drum 3 brings the aqueous liquid 6 along by the drum 3 and moves the aqueous liquid 6, which circulates through the lower container 8 in the washing drum 3.

The washing machine 1 is realized in particular in that in step (c) the drum 3 is enabled to move by a predetermined amplitude a _T Is inverted, the amplitude being less than 180 °, wherein the amplitude a _T Is the maximum deflection of the cylinder 3 during the reversal step in degrees. The drum 3 has an amplitude A of less than 180 DEG _T The movement ensures that the laundry 4 and the container 8 are not substantially redistributed inside the drum. As a result, the container 8 is repeatedly flushed with the aqueous liquid from all sides, in particular when the drum 3 is reversed.

In the embodiment of the washing machine according to the invention shown in fig. 1, the aforementioned variant of step (c) can be replaced or supplemented by the presence of a circulation pumping line 9, the aqueous liquid 6 being moved by circulation pumping through the circulation pumping line 9.

The movement of the aqueous liquid 6 in the lye container 2 can be effected by rotation or movement of the drum 3 and/or by operation of the circulating

pumping system

5,9, 14. The container 8 is thereby intensively flushed with the aqueous liquid 6 from all sides, whereby the container 8 can be quickly dissolved and the laundry treatment agent contained in the container 8 enters the aqueous liquid 6.

List of reference numerals

1. Washing machine

2. Lye container

3. Roller

4. Washing article

5. Lye pump, pump

6. Aqueous liquid

7. Control device

8. A detergent pad containing a detergent treatment agent; closed container

9. Circulating pumping pipeline

10. Outlet of alkali liquor container

11. Driving motor

12. Treatment agent sensor

13. Drainage pipeline

14. Alkali liquor container inlet of circulating pumping system

15. Heating device

16. Pressure sensor

17. Temperature sensor

18. Rotating shaft

19. Washing article driving device

20. Heating body groove

21. Fresh water input pipeline

22. Dosing device

23. And (4) a valve.

Claims

1. A method for treating laundry (4) in a washing machine (1) having:

an alkali liquor container (2);

a drum (3) rotatably supported about a substantially horizontal axis in the lye container (2) for receiving the laundry (4); and

a control device (7),

wherein the method comprises the following steps:

(a) -placing an open or closed container (8) containing a laundry treatment agent into a lower region of the drum (3);

(b) Injecting an aqueous liquid (6) into the lye container (2) in an amount W which is sufficient for the liquid level h in the drum (3) to have a predetermined minimum value h _min Wherein, in step (b), a predetermined minimum value h _min Is selected such that at least the drum (3) is in contact with the aqueous liquid (6) or a circulating pumping is effected by means of a circulating pumping system, wherein the circulating pumping requires that so much aqueous liquid (6) is contained in the circulating pumping system that it is sufficient for the liquid pumped out of the lye container (2) to be conducted back into the lye container (2) through the circulating pumping line (9) and for the aqueous liquid (6) present in the lye container (2) to be in contact with the laundry (4) in the drum in the circulating system;

it is characterized by also comprising the following steps:

(c) At a predetermined time t _set Moving the aqueous liquid (6) during more than 1 minute, the drum (3) being moved during the predetermined period of time such that no rotation of the drum (3) at an angle α ≧ 180 ° occurs, wherein in step (c) the aqueous liquid (6) is moved by the movement of the drum (3) during which the drum (3) entrains the aqueous liquid (6), and/or

(d) At a predetermined time t _set Moving the aqueous liquid (6) during > 1 minute, the drum (3) being in a stationary state during the predetermined period of time or being moved such that no rotation of the drum (3) at an angle α ≧ 180 ° occurs, wherein in step (d) the aqueous liquid (6) is moved by a circulating pumping system, wherein the circulating pumping system comprises a pump (5) for transporting the aqueous liquid (6) and a circulating pumping line (9).

2. Method according to claim 1, characterized in that the minimum value h of the liquid level _min Is selected so that the liquid level is higher than a container (8) located lower in the drum.

3. Method according to claim 1 or 2, characterized in that the drum (3) is brought to a predetermined amplitude a in step (c) and/or step (d) _T Is inverted, the amplitude is less than 180 DEG, wherein the amplitude A _T Is the maximum deflection of the drum (3) during the reversal step in degrees.

4. A method according to claim 3, characterized in that the drum (3) is moved in step (c) and/or step (d) at a speed of 50 rpm or less.

5. A method according to claim 1 or 2, characterized in that in step (b) the drum (3) is stopped during the injection of the aqueous liquid (6).

6. Method according to claim 1, characterized in that the quantity W of aqueous liquid is selected as a function of the load L of the laundry (4), wherein the relation between the quantity W of aqueous liquid and the load L is stored in the control device (7).

7. Method according to any one of claims 1, 2, 4 and 6, characterized in that the degree of movement in step (c) and/or step (d) is selected as a function of the load L of the laundry (4), wherein the relation between the degree of movement and the load L is stored in the control device (7).

8. The method of claim 7, wherein the degree of motion in step (c) and/or step (d) comprises an amplitude A _T The drum (3) is reversed by the amplitude, wherein the amplitude A _T Is the maximum deflection of the cylinder during the reversal step in degrees.

9. A method according to claim 7, wherein the washing machine (1) has a circulation pumping line (9) and the degree of movement of the aqueous liquid in step (d) comprises the circulation pumping speed of the aqueous liquid (6) in the circulation pumping line (9).

10. Method according to any one of claims 1, 2, 4, 6, 8 and 9, characterized in that the container (8) is a detergent pad having at least one cavity surrounded by a water-soluble film, wherein the detergent pad contains at least one liquid or powdered laundry treatment agent in this or these cavity(s).

11. Method according to any one of claims 1, 2, 4, 6, 8 and 9, characterized in that the laundry washing machine (1) comprises a treatment agent sensor (12) for determining the concentration of the laundry treatment agent, and in that in the method the dispensing of the laundry treatment agent from the container (8) in the aqueous liquid (6) is monitored by means of the treatment agent sensor (12) in order to determine a predetermined dispensing of the laundry treatment agent in the aqueous liquid (6).

12. Method according to any of claims 1, 2, 4, 6, 8 and 9, characterized in that the aqueous liquid (6) is injected in step (b) through the ring of the washing machine (1).

13. Method according to any one of claims 1, 2, 4, 6, 8 and 9, characterized in that said predetermined period of time t _set In the range of 1.5 to 5 minutes.

14. A washing machine having:

an alkali liquor container (2);

a control device (7),

characterized in that the washing machine is provided for carrying out the method according to any one of claims 1-13.

15. A washing machine (1) as in claim 14, characterized by a pump (5) for delivering an aqueous liquid (6) and by a circulating pumping line (9).