JPH06289755A - Washing method for roller - Google Patents

Abstract

PURPOSE:To well wash a used roller of an image forming device by an electrophotographic method without impairing the various performances required for the electrophotographic method without generating the dissolution and crack of its surface material by washing the roller with a ketone based solvent or a soln. mixture composed of the ketone and alcohol. CONSTITUTION:The roller of the image forming device by the electrophotographic method using developing toners contg. a styrene-acryl resin or a polyester resin as a binder resin is washed with the ketone based solvent or the soln. mixture composed of the ketone and the alcohol. The washing method is executed by immersing a part of a roller-shaped washing member 4 into the washing solvent 2 to impregnate the part with the solvent, pressing the roller 1 to be washed into contact longitudinally with the non-immersing part of the roller-shaped washing member 4 and rotating the washing member 4 in an arrow direction, thereby rubbing the surface of the roller 1 to be washed and washing the roller. The roller 1 to be washed is provided with a supporting body for the purpose of holding, etc. The roller 1 to be washed is held static or is rotated reverse from the rotating direction of the washing member 4 at the time the washing member rotates.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of cleaning various rollers of an image forming apparatus using an electrophotographic method, the rollers being contaminated with developing toner due to their use so that they can be reused. Specifically, it relates to a method for cleaning various rollers such as a charging roller, a developing roller, a transfer roller, a fixing roller, and a conveying roller, which are provided in an electrophotographic copying machine, a laser printer, a facsimile, a printing machine and the like.

[0002]

2. Description of the Related Art Conventionally, various rollers provided in an electrophotographic image forming apparatus such as an electrophotographic copying machine, a laser printer, a facsimile machine, a printing machine, etc. are normally used when the guaranteed period and the guaranteed number of sheets are exceeded. It has been discarded without being recycled as a used roller.

On the other hand, in fields other than electrophotography, as a method for cleaning a roller (mainly a metal roller), for example, a roller is immersed in a cleaning liquid for ultrasonic cleaning, or a roller is immersed in a solvent for cleaning a brush or the like. There are a method of rubbing the surface with a member, a method of immersing a roller in a cleaning solvent and heating to dissolve the dirt, and a method of spraying the cleaning solvent on the roller surface at a high speed to remove the dirt.

[0004]

In the past, it was difficult to recycle and reuse the above-mentioned waste roller. This is for the following reason.

Various rollers of an electrophotographic image forming apparatus, which are discarded, often have developing toner adhered to the surface and cannot be reused unless they are removed. In addition, various rollers of the image forming apparatus using the electrophotographic method often have a surface made of synthetic resin or synthetic rubber, which is inferior in strength and hardness to metal rollers. If you try, you risk damaging or deforming the surface.

If the above-mentioned cleaning methods of other fields are directly applied to this waste roller, the roller surface may be dissolved by the cleaning solvent, or cracks may occur, resulting in various performances required for the roller (for example, electrical resistance). , Hardness, surface roughness, roundness, slidability, etc.) may be impaired.

The present invention has been made to solve the above problems in the prior art. That is, an object of the present invention is to use various rollers of an image forming apparatus by electrophotography, which are used rollers having developing toner adhered to the surface thereof, for electrophotography without melting the surface material or generating cracks. An object of the present invention is to provide a method capable of satisfactorily cleaning without impairing various performances.

[0008]

The above object of the present invention is to provide a roller for an electrophotographic image forming apparatus using a developing toner containing a styrene-acrylic resin and / or a polyester resin as a binder resin, and a roller of a ketone solvent. Alternatively, it can be achieved by providing a method for cleaning a roller, which comprises cleaning with a mixed solvent of ketone and alcohol.

[0009]

The present invention has an unexpectedly excellent cleaning effect when a special type of roller, such as a roller of an electrophotographic image forming apparatus, is cleaned by using a ketone solvent or a mixed solvent of ketone and alcohol. Was completed and the special characteristics required in this field were not impaired.

The ketone-based solvent and the mixed solvent of ketone and alcohol exhibit the remarkable effect of the present invention when the adhered material on the roller is styrene-acrylic resin or polyester resin. These resins are generally used as a binder resin for toner. That is, the roller cleaned by the method of the present invention is a roller for an electrophotographic image forming apparatus using a developing toner containing a styrene-acrylic resin or a polyester resin as a binder resin.

As the washing solvent, either a ketone solvent or a mixed solvent of ketone and alcohol may be used. However, when the synthetic resin, synthetic rubber, or the like forming the roller has poor ketone dissolution resistance, it is desirable to use a mixed solvent of ketone and alcohol. In this case, the mixing ratio of alcohol and ketone is preferably ketone / alcohol = 3/7 (weight ratio) or a smaller amount of ketone than this. If the amount of ketone is larger than this, there is a risk that the synthetic resin or synthetic rubber of the roller may be dissolved, and the viscosity of the solvent may become high, which may hinder handling. Also,
At this mixing ratio, it is desirable that the amount of ketone is 1/9 or higher. If the amount of ketone is less than this, the cleaning effect tends to be insufficient. When a mixed solvent is used, the time for which the roller is in contact with the mixed solvent is preferably 20 minutes or less. Time to touch 2
If it is 0 minutes or longer, there is a risk that the synthetic resin or synthetic rubber of the roller may be dissolved.

As the ketone of the ketone type solvent and the mixed solvent, for example, methyl ethyl ketone, acetone, diethyl ketone, methyl isobutyl ketone and the like can be preferably used. As the alcohol of the mixed solvent, for example, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, amyl alcohol and the like can be preferably used.

As a method of cleaning the roller using such a cleaning solvent, a method of immersing the roller in the cleaning solvent and ultrasonic cleaning, a method of immersing a part or the whole of the roller in the cleaning solvent, a brush and a felt are used. Examples include a method of rubbing with a cleaning member such as a resin foam and a method of rubbing a roller with a cleaning solvent-impregnated brush, felt, resin foam or the like. Hereinafter, a specific mode will be described with reference to FIGS.

FIG. 1 is a schematic sectional view illustrating an ultrasonic cleaning method. In this embodiment, the roller 1 to be cleaned is immersed in the ultrasonic cleaning device 3 filled with the cleaning solvent 2, and ultrasonic vibration is propagated to the cleaning solvent 2 for cleaning.

FIG. 2 is a schematic sectional view showing an example of a method of cleaning a roller by rubbing it with a specific cleaning member. In this mode, the roller to be cleaned 1 is completely immersed in the cleaning solvent 2, the roller-shaped cleaning member 4 is horizontally abutted in the longitudinal direction of the roller to be cleaned 1, and is rotated in the direction of the arrow to rotate the roller to be cleaned. The surface of No. 1 is rubbed and washed. When the cleaning member 4 rotates, the cleaning roller 1 may be stationary or may be reversed with respect to the rotation direction of the cleaning member 4. In the embodiment shown in FIG. 2, the entire roller 1 to be cleaned is immersed in the cleaning solvent 2, but the present invention is not limited to this. For example, it is possible to immerse only a part of the roller 1 and bring the cleaning member 4 into contact with the non-immersed part for cleaning.

FIG. 3 is a schematic cross-sectional view showing another example of a method of rubbing a roller with a specific cleaning member for cleaning. In this mode, a part of the cleaning target roller 1 is immersed in the cleaning solvent 2, the belt-shaped cleaning member 4 is brought into horizontal contact with the non-immersed part of the cleaning target roller 1 in the longitudinal direction, and is moved in the arrow direction. By doing so, the surface is rubbed and washed. The belt-shaped cleaning member 4 is unwound from the unwinding roller 5 and wound around the winding roller 6 via the transport roller 7. When the cleaning member 4 moves, the cleaning target roller 1 may be stationary or rotated in a direction opposite to the moving direction of the cleaning member 4. In the embodiment shown in FIG. 3, only a part of the roller to be cleaned 1 is immersed in the cleaning solvent 2, but the present invention is not limited to this. For example, it is possible to immerse the entire roller 1 and bring the cleaning member 4 into contact therewith for cleaning.

FIG. 4 is a schematic sectional view showing an example of a method of cleaning a roller by rubbing it with a specific cleaning member. In this embodiment, a part of the roller-shaped cleaning member 4 is immersed in the cleaning solvent 2 to be impregnated, and the cleaning target roller 1 is brought into contact with the non-immersed part of the roller-shaped cleaning member 4 horizontally in the longitudinal direction to perform cleaning. By rotating the member 4 in the direction of the arrow, the surface of the cleaning roller 1 is rubbed and cleaned. The cleaning roller 1 is provided with a support for holding. When the cleaning member 4 rotates, the cleaning roller 1 may be stationary or may be reversed with respect to the rotation direction of the cleaning member 4.

FIG. 5 is a schematic sectional view showing an example of a method of cleaning a roller by rubbing it with a specific cleaning member. In this mode, the belt-shaped cleaning member 4 is washed with the cleaning solvent while the belt-shaped cleaning member 4 is being moved from the unwinding roller 5 to the winding roller 6 via the unwinding conveyance roller 7 in the direction of the arrow. The cleaning member 4 after being immersed in the cleaning roller 1 is horizontally abutted in the longitudinal direction of the roller 1 to be cleaned, and the surface is rubbed and cleaned. When the cleaning member 4 moves, the cleaning target roller 1 may be stationary or rotated in a direction opposite to the moving direction of the cleaning member 4.

Although the cleaning method has been illustrated with reference to FIGS. 1 to 5, any one of FIGS. 1 to 5 may be used when cleaning a single layer roller using a single material. on the other hand,
In the case of a multi-layer roller in which two or more kinds of materials are laminated, FIG.
Also, a method of cleaning the roller as shown in FIG. 5 without immersing the roller in the cleaning solvent is preferable. This is because the risk of melting the inner layer or peeling between layers is reduced unless the roller is dipped.

In addition, in the cleaning method shown in FIGS. 2 to 5, the roller-shaped or belt-shaped cleaning member is less likely to cause scratches or wear of the roller 1 to be cleaned, and is dissolved / swelled / cured in the cleaning solution. However, a member that can sufficiently absorb and retain the cleaning solvent is preferable, and various members such as a brush, felt, and resin foam may be appropriately selected and used.

After the cleaning described above, it is preferable to dry at the evaporation temperature of the solvent used.

[0022]

EXAMPLES The present invention will be described in more detail below with reference to examples.

Example 1 A laser printer (Laser Shot LBP-A404, manufactured by Canon Inc.) was used to image 3200 sheets (the binder resin of the developing toner was a mixture of styrene-acrylic resin and polyester resin). ), Immediately thereafter, the charging roller (outer diameter 12 mm, surface layer material is polyamide resin) was taken out from the process cartridge. The developing toner was found to be fixed on the charging roller.

This charging roller was washed according to the embodiment shown in FIG. Methyl ethyl ketone was used as the cleaning solvent 2, a felt roller (outer diameter 200 mm) was used as the cleaning member 4, the rotation speed of the felt roller was 200 rpm, and the cleaning time was 3 minutes. No sticking of developing toner was found on the charging roller after washing.

The current value was measured for each of the charging roller thus washed, the charging roller before cleaning (immediately after printing 3200 sheets) for comparison with this, and the unused charging roller, Further, the laser printer was attached to a new process cartridge and an image was printed by the laser printer. The results are shown in Table 1 below.

The current value is measured at 23 ° C. and 60% R.
Under the environment of H, the charging roller was brought into contact with an aluminum drum (outer diameter 30 mm) at a pressure of 500 g on one side, and DC −200 V was applied with AC V _{PP of} 500 V and frequency of 350 Hz superimposed on the core metal of the charging roller. The measurement was performed by measuring the direct current value and the alternating current value.

[0027]

[Table 1] As is clear from the results shown in Table 1, the current value of the charging roller was almost restored to an unused state by the cleaning method of the present invention, and the obtained image was also normal.

<Embodiment 2> Using the same apparatus and developing toner as in Embodiment 1, 120,000 sheets of images are printed, and immediately thereafter, a pressure roller (silicon rubber roller,
The outer diameter 18 mm) was taken out. This pressure roller was washed according to the embodiment shown in FIG. As the cleaning solvent 2,
Methyl ethyl ketone / isopropyl alcohol = 2/8
A belt-shaped cleaning member 4 using a mixed solvent (weight ratio)
For this, a felt belt was used, the moving speed of the felt belt was 15 mm / sec, and the cleaning time was 10 minutes. No sticking of developing toner was found on the charging roller after washing.

With respect to each of the pressure roller thus washed, the pressure roller before washing for comparison with this (immediately after 120,000 sheets are printed), and the unused pressure roller,
The surface roughness was measured, and the image was printed with the laser printer after being attached to the fixing device. The results are shown in Table 2 below.

Here, the surface roughness is measured using a surface roughness measuring instrument (trade name: Surfcoder SE-30H, manufactured by Kosaka Laboratory), and the ten-point average roughness (Rz) is measured according to JISB0601. It was done by doing.

[0031]

[Table 2] As is clear from the results shown in Table 2, the surface roughness of the pressure roller was almost restored to an unused state by the cleaning method of the present invention, and the obtained image paper was also free from stains.

<Embodiment 3> Using the same apparatus and developing toner as in Embodiment 1, 120,000 sheets of images are printed, and immediately after that, a transfer roller (foamed polyurethane roller, outer diameter 18 mm) is transferred from the transfer device. I took it out. Fixation of the developing toner was observed on this transfer roller. This transfer roller was ultrasonically cleaned according to the embodiment shown in FIG. As the cleaning solvent 2, a mixed solvent of methyl ethyl ketone / isopropyl alcohol = 3/7 (weight ratio) was used, the ultrasonic wave was 20 kHz, and the cleaning time was 15 minutes. No adherence of developing toner was found on the transfer roller after washing.

With respect to each of the transfer roller thus washed, the transfer roller before cleaning for comparison with this (immediately after printing 120,000 sheets), and the unused transfer roller,
The electric resistance value was measured, and the image was printed with the laser printer after being attached to the transfer device. The results are shown in Table 3 below.

Here, the electric resistance value was measured by placing the transfer roller on an aluminum drum (outer diameter: 30 mm) 500 on one side of the roller.
The electrical resistance value was determined by applying a DC voltage of 2000 V to the transfer roller and measuring the current value. This measurement was performed in an environment of 23 ° C. and 60% RH.

[0035]

[Table 3] As is clear from the results shown in Table 3, by the cleaning method of the present invention, the resistance value of the fixing roller was almost restored to an unused state, and the obtained image (character) did not have white spots.

[0036]

As described above, according to the cleaning method of the present invention, the styrene-acrylic resin and polyester resin adhered to the roller surface are well dissolved by the ketone solvent or the mixed solvent of ketone and alcohol. Can be removed. In addition, the surface material is not dissolved or cracked by cleaning, and various performances required for the electrophotographic method (for example,
(Electrical resistance, hardness, surface roughness, roundness, slidability, etc.) is not impaired.

Therefore, conventionally, the roller which has been discarded after the guaranteed period and the guaranteed number of sheets has been discarded can be easily recycled and reused by the cleaning method of the present invention.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing an embodiment using an ultrasonic cleaning method in the present invention.

FIG. 2 is a schematic cross-sectional view showing an aspect of rubbing a roller immersed in a cleaning solvent with a roller-shaped cleaning member in the present invention to clean the roller.

FIG. 3 is a schematic cross-sectional view showing a mode in which a roller immersed in a cleaning solvent is rubbed by a belt-shaped cleaning member to be cleaned in the present invention.

FIG. 4 is a schematic cross-sectional view showing an aspect in which a roller is rubbed and cleaned by a roller-shaped cleaning member immersed in a cleaning solvent in the present invention.

FIG. 5 is a schematic cross-sectional view showing an aspect in which a roller is rubbed and cleaned by a belt-shaped cleaning member immersed in a cleaning solvent in the present invention.

[Explanation of symbols]

 1 Cleaning Roller 2 Cleaning Solvent 3 Ultrasonic Cleaner 4 Cleaning Member 5 Unwinding Roller 6 Winding Roller 7 Conveying Roller 8 Support

Claims (5)

[Claims] 1. A roller of an electrophotographic image forming apparatus using a developing toner containing styrene-acrylic resin and / or polyester resin as a binder resin is washed with a ketone solvent or a mixed solvent of ketone and alcohol. A method for cleaning a roller characterized by: 2. The cleaning method according to claim 1, wherein the content of the ketone in the mixed solvent is 30% by weight or less. 3. The cleaning method according to claim 1, wherein the roller is immersed in the ketone solvent or a mixed solvent of ketone and alcohol and ultrasonically cleaned. 4. The cleaning is performed by immersing a part or all of the roller in the ketone solvent or a mixed solvent of ketone and alcohol, and rubbing the roller with a cleaning member selected from a brush, felt and resin foam. Item 3. The cleaning method according to Item 1 or 2. 5. The roller is cleaned by rubbing the roller with a cleaning member which is a member selected from a brush, a felt and a resin foam and which contains the ketone solvent or a mixed solvent of ketone and alcohol. Item 3. The cleaning method according to Item 1 or 2.