DECOLORIZATION METHOD AND WASHING MACHINE

Abstract

A decolorization method is a decolorization method of fabric using a washing machine configured to eject a washing liquid from a nozzle by a pressure at which the washing liquid is supplied from a supply source to the nozzle. The decolorization method includes spraying, to the fabric, a liquid column of the washing liquid extending from the nozzle or a droplet separated from the liquid column.

Description

The present application is based on, and claims priority from JP Application Serial Number 2022-186431, filed Nov. 22, 2022, the disclosure of which is hereby incorporated by reference herein in its entirety.

BACKGROUND

1. Technical Field

The present disclosure relates to a decolorization method and a washing machine.

2. Related Art

JP-A-2022-103961 describes a method of decolorizing fabric by spraying a dye extracting agent, a dye preventing agent, and the like to the fabric.

In the method described in JP-A-2022-103961, it is necessary to wash away the dye extracting agent, the dye preventing agent, and the like with a large amount of washing liquid after the fabric is decolorized. A method not using a dye extracting agent or a dye preventing agent is desired to reduce the consumption of a washing liquid.

SUMMARY

A decolorization method for solving the above problem is a decolorization method of fabric using a washing machine configured to eject a washing liquid from a nozzle by a pressure at which the washing liquid is supplied from a supply source to the nozzle, the decolorization method including spraying, to the fabric, a liquid column of the washing liquid extending from the nozzle or a droplet separated from the liquid column.

A washing machine for solving the above problem is a washing machine including a nozzle configured to eject a washing liquid by a pressure at which the washing liquid is supplied from a supply source, a pressurizing unit configured to pressurize the washing liquid between the supply source and the nozzle, and an acquisition unit configured to acquire a type of fabric, wherein a pressure at which the washing liquid is supplied from the supply source to the nozzle by the pressurizing unit is changed according to the type of the fabric acquired by the acquisition unit, and a liquid column of the washing liquid extending from the nozzle or a droplet separated from the liquid column is sprayed to the fabric.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram illustrating an example of a washing machine.

FIG. 2 is a schematic diagram illustrating a state transition of a washing liquid ejected from a nozzle.

FIG. 3 is a graph showing an impact pressure changing according to the distance between the nozzle and fabric.

FIG. 4 is a schematic diagram illustrating a state transition of the washing liquid ejected from the nozzle at a supply pressure higher than normal.

FIG. 5 is a graph showing an impact pressure changing according to the distance between the nozzle and the fabric when the washing liquid is supplied at a supply pressure higher than normal.

FIG. 6 is a schematic diagram illustrating a modified example of the washing machine.

DESCRIPTION OF EMBODIMENTS

One example of a washing machine and a decolorization method using the washing machine will be described below with reference to the drawings. The washing machine decolorizes fabric by washing the fabric. The washing machine decolorizes the fabric by means of so-called water jet. Thus, the washing liquid used by the washing machine is water. The washing liquid is not limited to water but may be ethanol, oil, or the like.

Washing Machine

As illustrated in FIG. 1, a washing machine 11 decolorizes fabric 99 by spraying a washing liquid to the fabric 99. The fabric 99 is woven fabric, knitted fabric, or the like. Printing is previously performed on the fabric 99 with pigments, dyes, or the like. That is, the fabric 99 is a medium that has been subjected to printing. The washing machine 11 sprays the washing liquid to the fabric 99, thereby removing the pigments, dyes, or the like from the fabric 99. With this, the fabric 99 is decolorized.

The washing machine 11 is coupled to a supply source 12. The supply source 12 supplies the washing liquid to a nozzle 15 described below. In one example, the supply source 12 is a water supply. The supply source 12 is not limited to the water supply but may be a tank that stores the washing liquid. In this case, the washing machine 11 may include the supply source 12.

The washing machine 11 includes a supply pipe 13. The supply pipe 13 is coupled to the supply source 12 and the nozzle 15. The washing liquid is supplied from the supply source 12 to the nozzle 15 through the supply pipe 13. The supply pipe 13 includes, for example, a hose.

The washing machine 11 may include a pump 14. The pump 14 is located at the supply pipe 13. In detail, the pump 14 is located at the supply pipe 13 between the supply source 12 and the nozzle 15. The pump 14 applies pressure to the washing liquid in the supply pipe 13. The pump 14 supplies the washing liquid from the supply source 12 to the nozzle 15 through the supply pipe 13. In one example, the pump 14 supplies the washing liquid from the supply source 12 to the nozzle 15 at a constant pressure. The washing liquid may be supplied to the nozzle 15 not only by the pressure by the pump 14 but also by the pressure by the supply source 12, for example. In this case, the supply source 12 supplies the washing liquid to the nozzle 15 at a constant pressure.

The washing machine 11 includes the nozzle 15. The nozzle 15 is configured to eject the washing liquid. A nozzle opening 16 is opened in the nozzle 15. The nozzle 15 ejects the washing liquid from the nozzle opening 16. In one example, the nozzle opening 16 is a hole on the order of nanometers.

The nozzle 15 ejects the washing liquid by a supply pressure. The supply pressure is a pressure acting on the washing liquid supplied from the supply source 12 to the nozzle 15. In one example, the supply pressure includes at least one of the pressure by the supply source 12 or the pressure by the pump 14. That is, the nozzle 15 ejects the washing liquid from the nozzle opening 16 by the pressure by the supply source 12, the pressure by the pump 14, or both of these pressures.

The washing machine 11 may include a pressurizing unit 17. The pressurizing unit 17 is configured to pressurize the washing liquid in the supply pipe 13. The pressurizing unit 17 assists the supply of the washing liquid from the supply source 12 to the nozzle 15. The pressurizing unit 17 pressurizes the washing liquid, which increases the supply pressure. That is, the pressurizing unit 17 pressurizes the washing liquid, so that the washing liquid is ejected from the nozzle 15 at a pressure higher than normal.

The pressurizing unit 17 includes a pressure chamber 18. The pressure chamber 18 is located at the supply pipe 13. In detail, the pressure chamber 18 is located at the supply pipe 13 between the pump 14 and the nozzle 15. The pressure chamber 18 stores the washing liquid.

The pressurizing unit 17 includes a pressurizing pump 19. The pressurizing pump 19 is coupled to the pressure chamber 18. The pressurizing pump 19 is, for example, an air pump. The pressurizing pump 19 pressurizes the washing liquid stored in the pressure chamber 18. Thus, the pressurizing unit 17 pressurizes the washing liquid in the supply pipe 13.

The washing machine 11 may include an acquisition unit 21 that acquires a type of the fabric 99. The acquisition unit 21 is, for example, a circuit including a CPU and a memory. The type of the fabric 99 includes a type of yarn, a weaving method of the fabric 99, a knitting method of the fabric 99, a thickness of the fabric 99, and the like. The acquisition unit 21 may acquire the type of the fabric 99 based on information input by a user from a personal computer, an operation panel, or the like. The acquisition unit 21 may acquire the type of the fabric 99 from an imaging unit 22 described below.

The washing machine 11 may include the imaging unit 22. The imaging unit 22 is configured to image the fabric 99. The imaging unit 22 may be a digital camera or an optical microscope. The type of the fabric 99 can be identified by analyzing the image captured by the imaging unit 22. The washing machine 11 may include an optical sensor instead of the imaging unit 22. The optical sensor acquires the light transmittance of the fabric 99. The acquisition unit 21 may acquire the type of the fabric 99 based on the light transmittance.

Decolorization Method

Next, a decolorization method of the fabric 99 by the washing machine 11 will be described.

As illustrated in FIG. 2, the state of the washing liquid ejected from the nozzle 15 transitions as the distance from the nozzle 15 increases. In detail, the washing liquid transitions in the order of a liquid column, a droplet, and a mist as the distance from the nozzle 15 increases. Immediately after being ejected from the nozzle 15, the washing liquid flies in a state of a liquid column continuous to the washing liquid in the nozzle 15. That is, the washing liquid flies in a state of a liquid column extending from the nozzle 15. Thereafter, the washing liquid is separated from the liquid column and thus flies in a droplet state. Finally, the washing liquid is further separated from a droplet and thus flies in a mist state.

The state of the washing liquid ejected from the nozzle 15 transitions in the order of a liquid column, a droplet, and a mist mainly due to air resistance acting on the washing liquid. This is also caused by the fact that the diameter of the nozzle opening 16 is very small. Thus, a region in which the washing liquid ejected from the nozzle 15 flies includes a liquid column region A1, a droplet region A2, and a mist region A3. The liquid column region A1 is a region in which the washing liquid ejected from the nozzle 15 is in a liquid column state. The droplet region A2 is a region in which the washing liquid ejected from the nozzle 15 is in a droplet state. The mist region A3 is a region in which the washing liquid ejected from the nozzle 15 is in a mist state.

When the washing machine 11 sprays the washing liquid to the fabric 99, the state of the washing liquid in contact with the fabric 99 is different according to the distance between the nozzle 15 and the fabric 99. When the fabric 99 is located in the liquid column region A1, the washing liquid in a liquid column state comes into contact with the fabric 99. When the fabric 99 is located in the droplet region A2, the washing liquid in a droplet state comes into contact with the fabric 99. When the fabric 99 is located in the mist region A3, the washing liquid in a mist state comes into contact with the fabric 99.

As illustrated in FIG. 3, the impact pressure acting on the fabric 99 is different according to the state of the washing liquid in contact with the fabric 99. Specifically, when the washing liquid in a droplet state comes into contact with the fabric 99, the impact pressure acting on the fabric 99 is higher than when the washing liquid in a liquid column state comes into contact with the fabric 99 and when the washing liquid in a mist state comes into contact with the fabric 99. That is, when the fabric 99 is located in the droplet region A2, the impact pressure acting on the fabric 99 is higher than when the fabric 99 is located in the liquid column region A1 and when the fabric 99 is located in the mist region A3.

When the fabric 99 is located in the liquid column region A1 and when the fabric 99 is located in the mist region A3, substantially the same impact pressure acts on the fabric 99. However, the landing position of the mist on the fabric 99 varies. Thus, the mist region A3 is not used for decolorization of the fabric 99. On the other hand, the liquid column and the droplet fly linearly from the nozzle 15. Thus, spraying the washing liquid in a liquid column state or in a droplet state to the fabric 99 enables decolorization of the fabric 99 by the impact pressure. That is, the fabric 99 can be directly decolorized by the washing liquid without use of a dye extracting agent and a dye preventing agent. The decolorization by the impact pressure consumes less washing liquid than when a dye extracting agent and a dye preventing agent are used.

The impact pressure acting on the fabric 99 is important for decolorization of the fabric 99. The larger the impact pressure is, the more easily the pigments, dyes or the like are removed from the fabric 99. On the other hand, when the impact pressure is large, the fabric 99 may be damaged. Thus, the impact pressure acting on the fabric 99 may be controlled. In the washing machine 11, the impact pressure acting on the fabric 99 can be controlled by adjusting the distance between the nozzle 15 and the fabric 99.

The impact pressure at which the fabric 99 is damaged is different according to the type of the fabric 99. That is, a preferable impact pressure for decolorization is different according to the type of the fabric 99. Thus, the distance between the nozzle 15 and the fabric 99 may be adjusted according to the type of the fabric 99. For example, when the fabric 99 not easily damaged is decolorized, the fabric 99 may be located in the droplet region A2. For example, when the fabric 99 easily damaged is decolorized, the fabric 99 may be located in the liquid column region A1. The distance between the nozzle 15 and the fabric 99 may be manually adjusted by the user or automatically adjusted by the washing machine 11.

As illustrated in FIG. 4, when the pressurizing unit 17 pressurizes the washing liquid, the liquid column region A1 becomes shorter than when the pressurizing unit 17 does not pressurize the washing liquid. That is, when the pressurizing unit 17 pressurizes the washing liquid, the washing liquid ejected from the nozzle 15 more rapidly transitions from a liquid column to a droplet than when the pressurizing unit 17 does not pressurize the washing liquid. Similarly, when the pressurizing unit 17 pressurizes the washing liquid, the droplet region A2 becomes shorter than when the pressurizing unit 17 does not pressurize the washing liquid. That is, when the pressurizing unit 17 pressurizes the washing liquid, the washing liquid ejected from the nozzle 15 more rapidly transitions from a droplet to a mist than when the pressurizing unit 17 does not pressurize the washing liquid. In the washing machine 11, as the supply pressure increases, the state of the washing liquid ejected from the nozzle 15 transitions more rapidly. Thus, the state of the washing liquid in contact with the fabric 99 can be controlled not only by adjusting the distance between the nozzle 15 and the fabric 99 but also by adjusting the pressurization by the pressurizing unit 17. Thus, the impact pressure acting on the fabric 99 can be controlled by adjusting the pressurization by the pressurizing unit 17. For example, the pressurization by the pressurizing unit 17 may be adjusted according to the type of the fabric 99. The pressurization by the pressurizing unit 17 may be manually adjusted by the user or may be automatically adjusted by the washing machine 11.

As shown in FIG. 5, when the pressurizing unit 17 pressurizes the washing liquid, the peak of the impact pressure is higher than when the pressurizing unit 17 does not pressurize the washing liquid. For example, when the fabric 99 not easily damaged is decolorized, the pressurizing unit 17 may pressurize the washing liquid. In FIG. 5, a graph indicated by a solid line is the impact pressure when the pressurizing unit 17 pressurizes the washing liquid. A graph indicated by a broken line is the impact pressure when the pressurizing unit 17 does not pressurize the washing liquid.

Operations and Effects

Next, actions and effects of the example described above will be described.

(1) The decolorization method includes spraying, to the fabric 99, a liquid column of the washing liquid extending from the nozzle 15 or a droplet separated from the liquid column. The state of the washing liquid ejected from the nozzle 15 by the pressure at which the washing liquid is supplied from the supply source 12 to the nozzle 15 transitions in the order of a liquid column, a droplet, and a mist as the distance from the nozzle 15 increases. When the washing liquid in a liquid column state or in a droplet state comes into contact with the fabric 99, the impact pressure of the washing liquid efficiently acts on the fabric 99. When the washing liquid in a mist state comes into contact with the fabric 99, the landing position of the washing liquid on the fabric 99 varies. Thus, the above method enables decolorization of the fabric 99 by the impact pressure of the washing liquid. That is, the fabric 99 can be decolorized without use of a large amount of washing liquid. Thus, the fabric 99 can be decolorized without use of a dye extracting agent or a dye preventing agent.

(2) The decolorization method includes changing the pressure at which the washing liquid is supplied from the supply source 12 to the nozzle 15. When the supply pressure is high, the region in which the washing liquid ejected from the nozzle 15 is a liquid column is shorter than when the supply pressure is low. That is, when the supply pressure is high, the washing liquid ejected from the nozzle 15 more rapidly transitions from a liquid column to a droplet than when the supply pressure is low. When the washing liquid in a droplet state comes into contact with the fabric 99, the impact pressure acting on the fabric 99 is higher than when the washing liquid in a liquid column state comes into contact with the fabric 99. As the impact pressure increases, the fabric 99 is more easily decolorized but may be damaged. The above method enables control of the impact pressure acting on the fabric 99. Thus, controlling the impact pressure enables decolorization of the fabric 99 while reducing the possibility of damaging the fabric 99.

(3) The decolorization method includes changing the pressure at which the washing liquid is supplied from the supply source 12 to the nozzle 15 according to the type of the fabric 99. This is because the ease of decolorization is different according to the type of the fabric 99. How easily the fabric 99 is damaged is different according to the type of the fabric 99. Thus, the above-described method enables the washing liquid to be sprayed to the fabric 99 at an appropriate impact pressure according to the type of the fabric 99.

Modified Example

The example described above may be modified for implementation as follows. The example described above and the following modified example may be combined with each other for implementation in so far as these examples are not technically inconsistent.

As illustrated in FIG. 6, the washing machine 11 may be coupled to a plurality of supply sources 12. In this case, the washing machine 11 may include a plurality of supply pipes 13, a plurality of pumps 14, and a plurality of pressurizing units 17 in a manner corresponding to the number of the supply sources 12. The plurality of supply sources 12 store different types of washing liquids.

The washing machine 11 may include a plurality of opening/closing valves 23 in a manner corresponding to the number of the supply pipes 13. Each of the plurality of opening/closing valves 23 is located at a corresponding one of the plurality of supply pipes 13. In this modified example, the opening/closing valve 23 is located at the supply pipe 13 between the nozzle 15 and the pressure chamber 18. Closing the opening/closing valves 23 stops the supply of the washing liquids. Thus, switching the plurality of opening/closing valves 23 can switch the washing liquid supplied to the nozzle 15. Thus, for example, an appropriate washing liquid can be selected according to the type of the fabric 99.

The supply pressure may be changed by changing not only the pressure by the pressurizing unit 17 but also the pressure by the pump 14. The supply pressure may be changed by changing the pressure by the supply source 12.

Technical Ideas

Hereinafter, technical ideas understood from the above-described example and modified example and working effects thereof will be described.

(A) The decolorization method is a decolorization method of fabric using a washing machine configured to eject a washing liquid from a nozzle by a pressure at which the washing liquid is supplied from a supply source to the nozzle, the decolorization method including spraying, to the fabric, a liquid column of the washing liquid extending from the nozzle or a droplet separated from the liquid column.

The state of the washing liquid ejected from the nozzle by the pressure at which the washing liquid is supplied from the supply source to the nozzle transitions in the order of a liquid column, a droplet, and a mist as the distance from the nozzle increases. When the washing liquid in a liquid column state or in a droplet state comes into contact with the fabric, the impact pressure of the washing liquid efficiently acts on the fabric. When the washing liquid in a mist state comes into contact with the fabric, the landing position of the washing liquid on the fabric varies. Thus, the above method enables decolorization of the fabric by the impact pressure of the washing liquid. That is, the fabric can be decolorized without use of a large amount of washing liquid. Thus, the fabric can be decolorized without use of a dye extracting agent and a dye preventing agent.

(B) The decolorization method may include changing the pressure at which the washing liquid is supplied from the supply source to the nozzle. When the pressure acting on the washing liquid is high, the region in which the washing liquid ejected from the nozzle is a liquid column is shorter than when the pressure acting on the washing liquid is low. That is, when the pressure acting on the washing liquid is high, the washing liquid ejected from the nozzle more rapidly transitions from a liquid column to a droplet than when the pressure acting on the washing liquid is low. When the washing liquid in a droplet state comes into contact with the fabric, the impact pressure acting on the fabric is higher than when the washing liquid in a liquid column state comes into contact with the fabric. As the impact pressure increases, the fabric is more easily decolorized but may be damaged. The above method enables control of the impact pressure acting on the fabric. Thus, controlling the impact pressure enables decolorization of the fabric while reducing the possibility of damaging the fabric.

(C) The decolorization method may include changing the pressure at which the washing liquid is supplied from the supply source to the nozzle according to a type of the fabric. The ease of decolorization is different according to the type of the fabric. How easily the fabric is damaged is different according to the type of the fabric. Thus, the above-described method enables the washing liquid to be sprayed to the fabric at an appropriate impact pressure according to the type of the fabric.

(D) The washing machine includes a nozzle configured to eject a washing liquid by a pressure at which the washing liquid is supplied from a supply source, a pressurizing unit configured to pressurize the washing liquid between the supply source and the nozzle, and an acquisition unit configured to acquire a type of fabric, wherein a pressure at which the washing liquid is supplied from the supply source to the nozzle by the pressurizing unit is changed according to the type of the fabric acquired by the acquisition unit, and a liquid column of the washing liquid extending from the nozzle or a droplet separated from the liquid column is sprayed to the fabric. According to the configuration described above, effects similar to those in the above-described decolorization method can be exerted.

Claims

1. A decolorization method of fabric using a washing machine configured to eject a washing liquid from a nozzle by a pressure at which the washing liquid is supplied from a supply source to the nozzle, the decolorization method comprising spraying, to the fabric, a liquid column of the washing liquid extending from the nozzle or a droplet separated from the liquid column.

2. The decolorization method according to claim 1, comprising changing the pressure at which the washing liquid is supplied from the supply source to the nozzle.

3. The decolorization method according to claim 2, comprising changing the pressure at which the washing liquid is supplied from the supply source to the nozzle according to a type of the fabric.

4. A washing machine comprising: a nozzle configured to eject a washing liquid by a pressure at which the washing liquid is supplied from a supply source;a pressurizing unit configured to pressurize the washing liquid between the supply source and the nozzle; andan acquisition unit configured to acquire a type of fabric, whereina pressure at which the washing liquid is supplied from the supply source to the nozzle by the pressurizing unit is changed according to the type of the fabric acquired by the acquisition unit, anda liquid column of the washing liquid extending from the nozzle or a droplet separated from the liquid column is sprayed to the fabric.