JP3201949B2 - Cleaning blade and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic cleaning blade applied to a cleaning process for removing toner from an electrophotographic photosensitive member, and a method of manufacturing the same. The present invention can be applied not only for cleaning the electrophotographic photosensitive member but also for cleaning a transfer drum and a transfer belt used for a transfer process, or an intermediate conveyance belt.

[0002]

2. Description of the Related Art Generally, in an electrophotographic process, at least respective processes of charging, exposure, development, transfer and cleaning are performed on an electrophotographic photosensitive member, and the cycle of these processes is repeated. That is, as shown in FIG. 1, a charging device 12, a document light image exposure mechanism 13, a developing device 14, and a transfer electrode 1 are provided around an electrophotographic photosensitive member 11.
5, the separation electrode 16, the charge erasing electrode 17, and the cleaning mechanism 18 are arranged in this order. The toner adhered to the electrostatic latent image on the surface of the photoreceptor in the developing process by the developing device 14 was fed from the surface of the photoreceptor by the feed roller 19 in the transfer process by the transfer electrode 15 and the separation electrode 16. It is moved to a transfer material 20 such as paper.

However, due to the reverse charging of the toner, unevenness and dirt on the surface of the photoreceptor, and insufficient energy of the transfer device, all the toner on the surface of the photoreceptor cannot be transferred to the transfer material. Remain. The residual toner blocks the photodischarge of the photoconductor in the photoconductor exposure process in the next cycle, and thus prevents the formation of a clear copy image. Therefore, the cleaning process after the transfer process is a very important process.

At present, the mainstream cleaning method is a method using a cleaning blade, and among them, a counter method having excellent cleaning properties is often used. That is, as shown in FIG. 1, the edge 23 a of the cleaning blade 23 held by the holder 22 fixed to the toner collecting device 21 is brought into contact with the photoconductor 11 so as to reverse in the rotation direction of the photoconductor 11. This is a mechanism for mechanically scraping off the residual toner on the surface.

[0005]

However, in the above-described cleaning method, the edge portion 23 of the cleaning blade 23 having excellent cleaning properties is provided.
“a” indicates that the edge portion 2 has a large frictional force with the photoconductor 11.
There was a drawback that 3a was easily turned upside down in the counter direction like 23b. Especially the cleaning blade 23
Since stress concentrates at both ends in the width direction of the edge portion 23a, the edge portion 23a is easily turned up.

In view of such circumstances, the present invention is directed to a cleaning blade for a toner-attached body such as an electrophotographic photosensitive member, a transfer drum or a transfer belt, and a cleaning blade which is unlikely to be turned up as described above, and a method of manufacturing the same. The task is to provide.

[0007]

According to a first aspect of the present invention, there is provided a cleaning blade for use in a cleaning unit for removing toner on a toner-attached body, wherein at least the cleaning blade is adapted to contact the toner-attached body. In the part that touches,
A cleaning blade having a coating layer made of a fluorine-based polymer in which a fluorine-based resin powder is dispersed.

Here, the coating layer is made of, for example, a fluorine-based material.
Resin powder and fluoropolymer dispersed in fluorosolvent
It is formed by applying the dispersed dispersion .

The coating layer is formed, for example, by spray coating or roll coating.

[0010] Further, a fluororesin-based lubricating layer may be provided as an upper layer or a lower layer on the coating layer at least at both ends in the width direction of the cleaning blade.

The fluororesin-based lubricating layer is formed, for example, by applying a fluororesin-based lubricant.

On the other hand, a second aspect of the present invention is a method of manufacturing a cleaning blade used in a cleaning unit for removing toner on a toner attached body, wherein at least a portion of the cleaning blade which comes into contact with the toner attached body has a fluorine-based material. Resin powder and
And a step of applying a dispersion obtained by dispersing a fluorine-based polymer in a fluorine-based solvent .

Here, a step of applying a fluororesin-based lubricant to at least both ends in the width direction of the cleaning blade by spray coating or roll coating may be included.

As described above, according to the present invention, the coating layer made of the fluorine-based polymer in which the fluorine-based resin powder is dispersed is provided on the edge of the cleaning blade that comes into contact with the photosensitive body. The coefficient of friction is reduced and initial turning is prevented. In particular, by further providing a fluororesin-based lubricating layer at both ends in the width direction where turning is likely to occur, turning at both ends where turning is likely to occur is reliably prevented.

Incidentally, it is conceivable that the turning-over can be prevented simply by rubbing a fluorine resin powder such as polytetrafluoroethylene (PTFE) or vinylidene fluoride (PVDF) on the edge of the cleaning blade. However, in this method, an excessive amount of fluororesin powder adheres to the edge portion, and the fluororesin powder flies up due to vibrations during assembly, transportation, or driving of the electrophotographic machine, and the inside of the electrophotographic machine is This is undesirable because it may cause a problem of contaminating other process components such as a charging roll and a transfer roll.

Therefore, it is preferable to form a coating layer made of a fluoropolymer in which a fluororesin powder is dispersed as in the present invention. Further, such a coating layer is made of a fluororesin powder and
It can be easily formed by applying a dispersion in which a fluorine-based polymer is dispersed in a fluorine-based solvent .

Examples of the fluorine-based polymer or fluorine-based resin powder that can be used in the present invention include polytetrafluoroethylene (PTFE) and vinylidene fluoride (PVDF). Further, as the fluorine-based solvent, xylene hexafluoride, an alternative chlorofluorocarbon-based solvent, and the like can be given.

Here, the mixing ratio of the fluorine resin powder, the fluorine polymer and the fluorine solvent is, for example, 1 to 5% by weight of the fluorine resin composition, 1 to 5% by weight of the fluorine polymer, 96% of the fluorine solvent. It is blended at a ratio of ~ 90% by weight.

The fluorine lubricant which can be used in the present invention includes rubron and polyflon (both trade names; manufactured by Daikin Industries, Ltd.), which are ethylene tetrafluoride resin, and Kynar (which is a vinylidene fluoride resin). (Trade name; manufactured by Elf Atochem Co., Ltd.) and the like, but are not limited thereto.

On the other hand, as the cleaning rubber elastic body,
For example, polyurethane rubber, silicone rubber, nitrile rubber, chloroprene rubber, and the like, but abrasion resistance,
In view of permanent distortion and contamination of the photoreceptor, polyurethane rubber is particularly desirable.

The cleaning blade of the present invention has a fluorine-based polymer layer containing a fluorine-based resin powder at least at an edge in contact with the photosensitive member. This method of forming the fluorine-based polymer layer is not particularly limited, the simple, fluorine fluororesin powder and a fluorine-based polymer
It can be formed by using a dispersion dispersed in a system solvent and applying, for example, by spray coating or roll coating.

Further, in order to surely prevent the turning-up at both ends in the width direction where the turning-up easily occurs, it is preferable to provide a fluorine-based lubricating layer at least at the edges of both ends. Such a fluorine-based lubricant layer may be simply formed by applying a fluorine-based lubricant by, for example, spray coating or roll coating.

In order to manufacture the cleaning blade of the present invention, for example, a preformed urethane sheet is processed into a strip shape and adhered to a holder (support plate). It is manufactured by applying a lubricant and further applying a dispersion in which a fluorine-based polymer and a fluorine-based resin powder are dispersed in a fluorine-based solvent.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (Examples 1 and 2) In both Examples 1 and 2, 1,4-butanediol and trimethylolpropane were mixed with the following urethane prepolymer dissolved by heating at the following compounding ratio and heated in advance. The mixture was poured into a set mold and cured by heating. After molding, width 15mm,
A rubber elastic body cut into a thickness of 2.0 mm and a length of 310 mm was formed, and the rubber elastic body was bonded to a support plate. Next, a fluorine-based lubricant is spray-coated on both ends in the width direction (longitudinal direction) of the edge portion of the rubber elastic body, and further thereon,
A dispersion obtained by dispersing the following fluorinated polymer and fluorinated resin powder in a fluorinated solvent was spray-coated on the front end portion over the entire region in the width direction to obtain a cleaning blade of the present invention.

(Blending in Example 1) Rubber elastic body (parts by weight) Ethylene adipate brepolymer 100 (Mn = 2000, NCO% = 6.5%) 1,4-butanediol 4.3 Trimethylolpropane 2 ・ Fluorine end lubricant Polyflon spray wax (manufactured by Daikin Industries, Ltd.) ・ Fluorine polymer and fluororesin powder PTFE, PVDF ・ Fluorine solvent xylene hexafluoride, HCFC-225

(Blending in Example 2) Rubber elastic body (parts by weight) Ethylene adipate prepolymer 100 (Mn = 2000, NCO% = 6.5%) 1,4-butanediol 4.3 Trimethylolpropane 2 ・ Fluorine lubricant at the end Lubron spray wax (manufactured by Daikin Industries, Ltd.) ・ Fluorine polymer and fluororesin powder PTFE, PVDF ・ Fluorine solvent xylene hexafluoride, HCFC-225

Comparative Example A rubber elastic body similar to that of Example 1 was obtained, cut into the same size, attached to a support plate, and a cleaning blade was obtained.

The cleaning blades manufactured in Examples 1 and 2 and Comparative Example 1 were mounted on an electrophotographic copying machine using an organic photoreceptor, and the turning properties were evaluated. In Examples 1 and 2, low temperature and low humidity were obtained. , Room temperature / humidity, high temperature
No turn-over occurred in any high-humidity environment, but in Comparative Example 1, turn-up occurred immediately.
Examples 1 and 2 were also excellent in cleaning performance.

[0029]

According to the cleaning blade of the present invention,
By significantly lowering the coefficient of friction between the toner deposit and the blade, it is possible to prevent initial turning without contaminating other process parts of the electrophotographic machine,
It is also excellent in cleaning performance.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view for explaining the operation of an electrophotographic apparatus using a cleaning blade.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 11 Electrophotographic photoreceptor 12 Charging device 13 Original light image exposure mechanism 14 Developing device 15 Transfer electrode 16 Separation electrode 17 Charge erasing exposure mechanism 18 Cleaning mechanism 19 Feed roll 20 Transfer material 21 Toner collection box 22 Holder 23 Cleaning blade 23a Normally functioning edge of cleaning blade 23b Edge of cleaning blade when turned up

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G03G 21/10

Claims (6)

(57) [Claims] 1. A cleaning blade for use in a cleaning unit for removing toner on a toner attached body, wherein the cleaning blade is made of a fluorine-based polymer in which a fluorine-based resin powder is dispersed at least in a portion in contact with the toner attached body. A cleaning blade having an application layer. 2. A method according to claim 1, wherein the coating layer is, fluoride
Separation of base resin powder and fluorine polymer into fluorine solvent
A cleaning blade formed by applying a dispersed dispersion . 3. The cleaning blade according to claim 1, wherein the cleaning blade has a fluororesin lubricating layer as an upper layer or a lower layer on at least both ends in the width direction of the cleaning layer. 4. The cleaning blade according to claim 1, wherein the fluororesin-based lubricating layer is formed by applying a fluororesin-based lubricant. 5. A method of manufacturing a cleaning blade used for a cleaning unit for removing toner on a toner adhered body, wherein at least a portion in contact with the toner adhered body includes a fluorine resin powder and a fluorine polymer. system
A method for producing a cleaning blade, comprising a step of applying a dispersion dispersed in a solvent . 6. The method of manufacturing a cleaning blade according to claim 5, further comprising a step of applying a fluororesin-based lubricant to at least both ends in the width direction of the cleaning blade.