JPH09288441A - Method and device for image forming - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain copied image which have high image quality and are stabi lized over a long term by making the viscosity average molecular weight of a resin constituting the uppermost layer of an organic photoreceptor equal to or high than a specified value and also making the effective driving torque of a brush roller within a specified range. SOLUTION: The viscosity average molecular weight of the resin constituting the uppermost layer of the organic photoreceptor 1 is >=5×10<4> , and also the effective driving torque T of the brush roller 4 is >=0.1kgf.cm and <=2.0kgf.cm. The torque T is defined as a difference (T1 -T2 ) between a driving torque T1 at the time of rotating a photoreceptor drum 1 at the same rotational speed as normal copying operation and rotating the roller 4 at specified rotational speed in a state where the drum 1 and the roller 45 are installed at specified positions and are brought into contact and the driving torque T2 at the time of rotating the roller 4 at the same rotational speed as the time of measuring the torque T1 in a state where the drum 1 is detached and the roller 4 is not brought into contact with the drum 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image forming method and apparatus used in copying machines, printers and the like, and more particularly to a photoconductor cleaning method in the image forming method and apparatus.

[0002]

2. Description of the Related Art In the electrophotographic image forming method of the Carlson method used in copying machines and the like, an electrostatic latent image is formed by uniformly charging a photoreceptor and then erasing the charge imagewise by exposure. Then, the electrostatic latent image is developed and visualized with toner, and then the toner is transferred onto a recording material such as paper and then fixed to complete the image formation.

However, not all of the toner on the photoconductor is transferred, and a part of the toner remains on the photoconductor, so that the photoconductor is repeatedly used after a cleaning process. If the cleaning is not perfect, it is impossible to obtain a high-quality copied image without stains when repeatedly forming an image.

A fur brush, a magnetic brush, a blade or the like is typical as the cleaning means, but the blade is mainly used from the viewpoints of performance, constitution and the like. A plate-shaped rubber elastic body is generally used as the blade member at this time.

The electrophotographic photosensitive member has not only the electrophotographic characteristics such as good charging characteristics and sensitivity but also small dark decay, but also physical characteristics such as printing durability, abrasion resistance and scratch resistance upon repeated use. It is also required to have good properties and resistance to ozone, NOx generated during corona discharge, ultraviolet rays during exposure, and the like.

Conventionally, selenium has been used as an electrophotographic photoreceptor.
Inorganic photoconductors having an inorganic photoconductive substance such as zinc oxide and cadmium sulfide as a main component of a photosensitive layer have been widely used. However, since many of these inorganic photoconductors are harmful to the human body, a problem occurs when they are discarded.

In recent years, the development of organic photoconductors using organic substances which are non-polluting has been actively pursued and is being put to practical use. Above all, the charge generation function and the charge transport function are shared by different substances,
There is active development of a function-separated type photoconductor in which substances exhibiting respective functions can be selected from a wide range according to desired characteristics, and there is a trend to put an organic photoconductor with high sensitivity and durability into practical use.

However, these organic photoconductors have a large amount of film wear during use as compared with the conventional inorganic photoconductors, which causes a problem that sensitivity is lowered. On the other hand, attempts have been made to increase the mechanical durability of the surface layer of the photoconductor to reduce film wear during use. However, in such a case, on the contrary, the surface is not cleaned due to wear of the photoconductor,
Image defects due to the effects of surface deterioration and adhered matter have become a problem.

From these phenomena, in order to maintain good image quality, it is considered that the organic photoreceptor needs to be appropriately worn in order to forcibly remove surface deterioration products and adhered products during use. It became so.

However, as a result of diligent studies, we have found that the problem of surface deterioration due to the use of a photoconductor is relatively small, and the influence of deposits on the surface is large. That is, it has been found that in order to maintain the image quality, it is important to scrape the photosensitive member to the extent that it does not need to be excessively scraped and that suppresses adhesion to the surface.

Further, the main factor of the process of depleting the photoconductor is due to the blade cleaning. However, with the elastic rubber blade alone, the proper abrasion which suppresses the above-mentioned wear is maintained while maintaining the cleaning performance. It has proven difficult to do.

On the other hand, a brush has been conventionally proposed as another means for cleaning, but it is difficult to obtain a cleaning performance equivalent to that of an elastic rubber blade only with a brush. However, there is a problem that the cost is increased and an installation space is secured, and at the same time, mechanical stress applied to the photoconductor is increased, and the life of the photoconductor is shortened.

[0013]

SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming method and apparatus capable of obtaining a high quality and stable copied image for a long period of time, and to prevent image unevenness, black streaks and fog used at that time. It is to develop a cleaning method having extremely excellent cleaning performance that does not occur.

[0014]

The object of the present invention is achieved by adopting the following constitution.

(1) In the image forming method, which comprises a step of cleaning the toner remaining on the photosensitive member with a brush roller and an elastic rubber blade after the moving toner image on the organic photosensitive member is transferred onto a recording material, The viscosity average molecular weight of the resin constituting the outermost surface layer of the organic photoreceptor is 5 ×
10 ⁴ or more, and the effective driving torque T of the brush roller specified below is 0.1 kgf · cm or more,
An image forming method, which is 2.0 kgf · cm or less.

Effective driving torque T = T ₁ -T ₂ T ₁ : Driving torque of the brush roller when the brush roller and the photoconductor are in contact T ₂ : The brush roller when the brush roller and the photoconductor are not in contact Driving torque (2) The image forming method according to (1), wherein the resin is a polycarbonate resin.

(3) In an image forming apparatus having a mechanism for cleaning the toner remaining on the photosensitive member with a brush roller and an elastic rubber blade after transferring the toner image on the moving organic photosensitive member to a recording material, The viscosity average molecular weight of the resin constituting the outermost surface layer of the organic photoreceptor is 5 ×
10 ⁴ or more, and the effective driving torque T of the brush roller specified below is 0.1 kgf · cm or more,
An image forming apparatus having a weight of 2.0 kgf · cm or less.

Effective drive torque T = T ₁ -T ₂ T ₁ : Drive torque of the brush roller when the brush roller and the photoconductor are in contact T ₂ : The brush roller when the brush roller and the photoconductor are not in contact Driving Torque As shown in FIG. 1, the brush used in the present invention preferably has a structure in which a fur brush is installed on the surface of a cylindrical support through an adhesive layer.

In FIG. 1, 1 is a photoreceptor, 2 is a cylindrical brush support, 3 is an adhesive layer, and 4 is a brush roller.

Any material can be used as the constituent material of the brush according to the present invention, but it is preferable to use a fiber-forming polymer which is hydrophobic and has a high dielectric constant.
Examples of such high-molecular polymers include rayon, nylon, polycarbonate, polyester, methacrylic resin, acrylic resin, polyvinyl chloride, polyvinylidene chloride, polypropylene, polystyrene, polyvinyl acetate, styrene-butadiene copolymer, and vinylidene chloride. -Acrylonitrile copolymer, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer, silicone resin, silicone-alkyd resin, phenol formaldehyde resin, styrene-alkyd resin, polyvinyl acetal (for example, polyvinyl Butyral) and the like. These resins can be used alone or as a mixture of two or more.
Particularly preferably, rayon, nylon, polyester,
Acrylic and polypropylene.

The brush may be electrically conductive or insulative, and a material having a low resistance substance such as carbon contained in its constituent material and adjusted to have an arbitrary resistance can be used.

The support used in the brush of the present invention is mainly metal such as stainless steel or aluminum, paper,
Plastic or the like is used, but is not limited thereto.

The effective driving torque T of the brush roller used in the present invention is 0.1 kgf · cm or more and 2.0 kg.
f · cm or less, preferably 0.5 kgf · cm
As described above, the pressure is 1.5 kgf · cm or less. The effective drive torque T referred to here means that the photosensitive drum and the brush roller are set at predetermined positions, and the photosensitive drum is rotated at the same rotation speed as a normal copying operation when the photosensitive drum and the brush roller are in contact with each other. , The driving torque T ₁ when the brush roller is rotated at a predetermined rotation speed, and the rotation speed of the brush roller at the same rotation speed as when T _{1 is} measured with the photoconductor drum removed and the brush roller not in contact with the photoconductor drum. It is defined as the difference (T ₁ −T ₂ ) of the driving torque T ₂ when rotating. This effective driving torque means a load applied to the brush, which is generated by the relative movement of the photosensitive drum and the brush roller. This load corresponds to the rubbing force received from the brush from the viewpoint of the photoconductor drum, and defining the range means that the photoconductor needs to rub with an appropriate force. Effective driving torque T is 0.1 kgf · c
If it is smaller than m, the frictional force of the brush on the photoconductor drum is small, so that filming of the toner or paper dust on the photoconductor surface cannot be suppressed, and defects such as unevenness occur on the image. If it is larger than 2.0 kgf · cm, the amount of abrasion of the photoconductor drum by the brush is too large, and the amount of wear of the photoconductor becomes large, causing fog due to sensitivity decrease or scratches on the photoconductor surface. This is a problem because streak failure may occur on the image.

As shown in FIG. 2, the torque is measured by rotating the cylindrical brush support 2 of the brush roller 4 through a micro coupling 7 (manufactured by Tokushu Seiko Co., Ltd.) and using a rotary shaft torque detector MD-204R (8). Connected to (Ono Sokki Co., Ltd.), the torque when rotating by the motor 9 so as to reach the set rotation speed is 10 digital torque calculation display TS-3.
It was read at 600A (manufactured by Ono Sokki Co., Ltd.).

The brush has a single fiber thickness of 6 to 30 denier and a fiber density of 4.5 × 10 ^{2 to} 15.5 × 10 ² f / c.
m ² is preferred, but not particularly limited.

If necessary, a member (flicker) for knocking off the toner and foreign matter attached to the brush roller 4 from the brush may be provided.

As shown in FIG. 1, the elastic rubber blade used in the present invention is preferably constructed so as to have a free end on a supporting member.

In FIG. 1, 1 is an organic photoconductor, 4 is a brush roller, 5 is an elastic rubber blade, and 6 is a support member.

The free end of the elastic rubber blade is preferably in pressure contact with the opposite side (counter) to the rotating direction of the photosensitive member.

The rubber hardness of the elastic rubber blade is JIS
A 60-70 °, rebound resilience 30-70%, Young's modulus 30-60 kgf / cm ² , thickness 1.5-3.0
mm, free length 7 to 12 mm, pressing force on the photoconductor is 5
It is preferably 30 g / cm, but is not particularly limited.

The constitution of the photoconductor used in the present invention is as follows.

The charge generating substance (CGM) is not particularly limited, but examples thereof include a phthalocyanine pigment, a polycyclic quinone pigment, an azo pigment, a perylene pigment, and an indigoid pigment.

In particular, the electrophotographic photoreceptor of the present invention contains a fluorenone disazo pigment, an imidazole perylene pigment,
The use of anthanthrone pigment or oxytitanyl phthalocyanine pigment shows markedly improved effects in terms of sensitivity, durability and image quality.

These charge generating substances may be used alone or in combination of two or more.

The charge transporting material (CTM) is not particularly limited, but examples thereof include oxazole derivatives, oxadiazole derivatives, thiazole derivatives, thiadiazole derivatives, triazole derivatives, imidazole derivatives, imidazolone derivatives, imidazolidine derivatives, bisimidazolidine derivatives. , Styryl compound, hydrazone compound, pyrazoline derivative, amine derivative, oxazolone derivative, benzothiazole derivative, benzimidazole derivative, quinazoline derivative, benzofuran derivative, acridine derivative, phenazine derivative, aminostilbene derivative, poly-N-vinylcarbazole, poly-1 -Vinylpyrene,
Examples thereof include poly-9-vinyl anthracene.

Further, as the charge transporting substance, a substance which has an excellent ability to transport holes generated upon irradiation with light and which is suitable for combination with an organic charge generating substance (CGM) is preferable.

Since the charge-generating substance and the charge-transporting substance themselves have poor film-forming ability, various binders may be used to form the photosensitive layer.

Although any binder resin can be used for forming the photosensitive layer, it is preferable to use a film-forming high molecular polymer which is hydrophobic, has a high dielectric constant and is electrically insulating. . Examples of such high molecular weight polymers include polycarbonate resin, polyester resin, methacrylic acid resin, acrylic resin, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyvinyl acetate, styrene-butadiene copolymer, vinylidene chloride-acrylonitrile copolymer. Coal, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer, silicone resin, silicone-alkyd resin, phenol formaldehyde resin, styrene-alkyd resin, poly-N-vinylcarbazole, polyvinyl acetal (For example, polyvinyl butyral) and the like. These binder resins can be used alone or as a mixture of two or more kinds.

The resin used for the outermost surface layer has a viscosity average molecular weight of 5 × 10 ⁴ or more, preferably 10
× 10 ⁴ or more. The viscosity average molecular weight M is defined by the following formula.

[Η] = 1.23 × 10 ⁻⁴ M ^0.83 η _SP /c=[η]+0.43 [η] ² c where η _SP is the viscosity at concentration c (20 ° C., Ostwald viscosity) Tube used), c = 0.6 g / 100 ml (methylene chloride).

When the viscosity average molecular weight is less than 5 × 10 ⁴ , the abrasion loss during cleaning increases and the sensitivity of the photosensitive member decreases, so that image defects such as fogging occur and the object of the present invention is achieved. Can not. Further, as the binder resin used for the outermost surface layer, a polycarbonate resin is particularly preferable since it exhibits excellent characteristics, and more preferably B
PA-PC, BPZ-PC and the like.

An antioxidant may be added to the photosensitive layer for the purpose of preventing ozone deterioration. As an antioxidant,
Hindered phenol, hindered amine, paraphenylenediamine, arylalkane, hydroquinone, spirochroman, spiroindanone and their derivatives,
Examples include organic sulfur compounds and organic phosphorus compounds.

Specific examples of these compounds include those disclosed in JP-A-6-61.
3-14154, 63-18355, 63-4
4662, 63-50848, 63-50849.
No. 63-58455, No. 63-71856, No. 63-71857 and No. 63-146046.

The amount of the antioxidant added is 0.1 to 100 parts by weight, preferably 1 to 50 parts by weight, particularly preferably 5 to 25 parts by weight, based on 100 parts by weight of CTM.

As the conductive support used in the construction of the organic photoconductor, the following are mainly used, but they are not limited thereto.

1) Metals such as aluminum and stainless steel 2) Supports such as paper or plastic provided with a thin metal film such as aluminum, palladium or gold by laminating or vapor deposition 3) Supports such as paper or plastic film above,
A layer provided by coating or vapor deposition of a conductive compound such as a conductive polymer, indium oxide, or tin oxide.

The organic photoreceptor is composed of a charge generation layer (C
GL), charge transport layer (CTL), and if necessary,
A protective layer, an intermediate layer, a barrier layer, an auxiliary layer such as an adhesive layer may be laminated.

The intermediate layer functions as an adhesive layer or a blocking layer, and in addition to the binder resin,
For example, polyvinyl alcohol, ethyl cellulose, carboxymethyl cellulose, casein, copolymer nylon,
N-alkoxymethylated nylon, starch and the like are used.

Solvents or dispersion media used for forming the charge generation layer and the charge transport layer include butylamine, diethylamine, ethylenediamine, isopropanolamine, triethanolamine, triethylenediamine,
N, N-dimethylformamide, acetone, methyl ethyl ketone, cyclohexanone, benzene, toluene, xylene, chloroform, 1,2-dichloroethane, 1,
2-dichloropropane, 1,1,2-trichloroethane, 1,1,1-trichloroethane, trichloroethylene, tetrachloroethane, dichloromethane, tetrahydrofuran, dioxane, methanol, ethanol, isopropanol, ethyl acetate, butyl acetate, dimethyl. Examples thereof include sulfoxide and methyl cellosolve.

The morphology of the organic photoconductor is illustrated in FIGS.

As shown in FIGS. 3 (a) and 3 (b), the organophotoreceptor comprises, on a conductive support 11, a CGL 12 containing CGM according to the present invention as a main component and a CTL 13 containing CTM as a main component. A photosensitive layer 14 made of a laminated body is provided.

The photosensitive layer 14 'may be provided via the intermediate layer 15 provided on the conductive support 11 as shown in FIGS.

As described above, when the photosensitive layer 14 has a two-layer structure, an electrophotographic photosensitive member having excellent electrophotographic characteristics can be obtained.

Further, in the present invention, as shown in (e) and (f) of FIG.
Photosensitive layer 14 ″ having fine particle-shaped CGM 17 dispersed therein
May be provided directly on the conductive support 11 or via the intermediate layer 15.

Further, a protective layer may be provided on the photosensitive layer 14 if necessary.

When the photosensitive layer 14 has a two-layer structure as shown in FIG. 1 (a), the CGL 12 is an intermediate layer such as an adhesive layer or a blocking layer directly on the conductive support 11 or the CTL 13 or as required. In addition to the above, it can be formed by the following method.

(1) Vacuum evaporation method (2) Method of applying a solution of CGM dissolved in a suitable solvent (3) CGM is made into fine particles in a dispersion medium by a ball mill, sand grinder or the like, and if necessary, a binder. A method of applying a dispersion obtained by mixing and dispersing with.

That is, specifically, a vapor deposition method such as vacuum deposition, sputtering, or CVD, or a coating method such as dipping, spraying, blade, or roll method is arbitrarily used.

The thickness of the CGL thus formed is preferably 0.01 to 5 μm, more preferably 0.05 to 3.0 μm. The composition ratio in this CGL is such that the binder is 0.1 to 1 part by weight of CGM.
It is preferable to use 5 parts by weight, but when forming the photosensitive layer 14 ″ in which fine particle CGM is dispersed, it is preferable to use the binder in an amount of 5 parts by weight or less with respect to 1 part by weight of CGM.

The CTL 13 can be formed in the same manner as the CGL 12.

At this time, the thickness of the CTL 13 can be changed if necessary, but is usually preferably 5 to 30 μm.

The composition ratio in this CTL is CTM1.
The binder is preferably 0.5 to 5 parts by weight with respect to parts by weight.

[0063]

The present invention will be described in detail below with reference to examples, but the embodiments of the present invention are not limited thereto.

(Example 1) Polyamide resin CM-800
30 g of 0 (manufactured by Toray Industries, Inc.) was put into a mixed solvent of 900 ml of methanol and 100 ml of 1-butanol, and dissolved by heating at 50 ° C. This liquid has an outer diameter of 80 mm and a length of 355.5 mm.
Coated on a cylindrical aluminum conductive support of
A μm thick intermediate layer was formed.

Next, 2 g of polyvinyl butyral resin S-REC BX-1 (manufactured by Sekisui Chemical Co., Ltd.) was dissolved in a mixed solvent of 700 ml of methyl ethyl ketone and 300 ml of cyclohexanone, and 3 g of CGM (exemplified compound A-1) was mixed therein and a sand mill was used. Dispersed for 10 hours. This solution was applied onto the intermediate layer to form a charge generation layer having a thickness of 0.3 μm.

Next, CTM (Exemplified Compound B-1) 150
g and 200 g of bisphenol Z type polycarbonate (BPZ-PC) (manufactured by Mitsubishi Gas Chemical Co., Inc.) having a viscosity average molecular weight Mv of 8 × 10 ⁴ were dissolved in 1000 ml of dichloromethane. This solution was applied onto the charge generation layer and then dried at 100 ° C. for 1 hour to form a 20 μm thick charge transport layer.

Thus, a laminated photoreceptor sample 1 including the intermediate layer, the charge generation layer and the charge transport layer was obtained.

[0068]

Embedded image

The photoreceptor prepared as described above was incorporated in an analog copying machine U-BIX4155 (manufactured by Konica Corporation).

Further, an elastic rubber blade having a rubber hardness of JIS A 65 °, a repulsion elasticity of 40%, a thickness of 1.9 mm, and a free length of 9 mm is pressed at a contact angle of 20 ° against the rotation of the photosensitive member in the counter direction with a pressing force of 18 g. / Cm contacted.

Further, an acrylic brush having a single fiber thickness of 6.2 denier and a fiber density of 9.3 × 10 ² f / cm ² was applied to a SUS core metal support having a diameter of 6 mm so that the outer diameter was 15 mm. The produced roller was installed below the blade so that the amount of bite into the photosensitive drum was 1 mm, and the roller was set to operate in the forward direction in synchronization with the photosensitive member at a rotation speed of 500 rpm. Further, at this time, a flicker for scraping off the toner was provided so that the amount of bite into the brush was 1 mm.

The effective driving torque T at this time is 0.41 k.
gf · cm.

In this state, a real copying test of 200,000 copies was conducted to evaluate the quality of the copied image. (Example 2) In the laminated photoreceptor sample 1, the resin of the charge transport layer was BPZ- with a viscosity average molecular weight Mv of 5.0 x 10 ⁴ .
A laminated photoreceptor sample 2 was obtained in the same manner except that it was replaced with PC.

In addition, the actual copying test of 200,000 copies was conducted in the same manner as in Example 1 except that the single fiber thickness of the brush was changed to 15 denier.

Further, the effective drive torque T of the brush at this time
Was 0.72 kgf · cm.

Example 3 In the laminated photoreceptor sample 1,
The resin of the charge transport layer has a viscosity average molecular weight Mv of 12.0 × 1.
Was replaced by 0 ⁴ BPZ-PC was obtained a laminated photoreceptor sample 3 in the same manner.

In Example 1, the brush has a single fiber thickness of 8.5 denier and a fiber density of 11.6 × 10 ² f.
An actual copying test of 200,000 copies was conducted in the same manner except that the material was polypropylene at a rate of / cm ² .

Further, the effective driving torque T of the brush at this time
Was 1.30 kgf · cm.

Example 4 As the photoconductor, the laminated photoconductor sample 2 was used.

In Example 1, the brush has a single fiber thickness of 6.2 denier and a fiber density of 5.4 × 10 ² f /
A 200,000-copy live-copy test was conducted in the same manner except that the size was changed to cm ² .

Further, the effective drive torque T of the brush at this time
Was 0.23 kgf · cm.

Example 5 As the photoconductor, the laminated photoconductor sample 1 was used.

In Example 1, the brush has a single fiber thickness of 10 denier and a fiber density of 10.9 × 10 ² f /
20 cm in the same manner except that nylon was used as the material for cm ^2.
A live-copy test of 10,000 copies was conducted.

Further, the effective drive torque T of the brush at this time
Was 1.45 kgf · cm.

Example 6 As the photoconductor, the laminated photoconductor sample 1 was used.

In Example 1, the brush has a single fiber thickness of 30 denier and a fiber density of 7.0 × 10 ² f / c.
A live-action test of 200,000 copies was conducted in the same manner except that the material was rayon at m ² .

Further, the effective drive torque T of the brush at this time
Was 2.03 kgf · cm.

Example 7 In the laminated photoreceptor sample 1,
The resin of the charge transport layer has a viscosity average molecular weight Mv of 10.0 × 1.
0 ⁴ Bisphenol A type polycarbonate (BPA-
A laminated photoreceptor sample 4 was obtained in the same manner except that it was replaced with PC).

The other settings were the same as in Example 3, and the actual copying test of 200,000 copies was performed.

At this time, the effective drive torque T of the brush is
It was 1.42 kgf · cm.

(Comparative Example 1) As the photoreceptor, the laminated photoreceptor sample 1 was used.

In addition, the actual copying test of 200,000 copies was conducted in the same manner as in Example 4 except that the fiber thickness of the brush was 4 denier and the fiber density was 5.4 × 10 ² f / cm ² .

Further, the effective drive torque T of the brush at this time
Was 0.08 kgf · cm.

(Comparative Example 2) As the photoreceptor, the laminated photoreceptor sample 1 was used.

A 200,000-copy actual copying test was conducted in the same manner as in Example 6 except that the fiber density of the brush was set to 11.6 × 10 ² f / cm ² .

Further, the effective drive torque T of the brush at this time
Was 2.26 kgf · cm.

Comparative Example 3 In the laminated photoreceptor sample 1,
The resin of the charge transport layer has a viscosity average molecular weight Mv of 2.0 × 10
^A laminated photoconductor sample 5 was obtained in the same manner except that the BPZ-PC of ⁴ was replaced.

Other settings were the same as in Example 2, and a 200,000-copy actual copying test was conducted.

At this time, the effective drive torque T of the brush is
It was 0.92 kgf · cm.

(Comparative Example 4) In the laminated photoreceptor sample 1,
The resin of the charge transport layer has a viscosity average molecular weight Mv of 1.3 × 10
^A laminated photoreceptor sample 6 was obtained in the same manner except that the BPA-PC of ⁴ was replaced.

Other settings were the same as in Example 3, and a 200,000-copy actual copying test was conducted.

At this time, the effective drive torque T of the brush is
It was 1.31 kgf · cm.

(Comparative Example 5) In the laminated photoreceptor sample 1,
The resin of the charge transport layer has a viscosity average molecular weight Mv of 3.0 × 10
^A laminated photoconductor sample 7 was obtained in the same manner except that the BPZ-PC of ⁴ was replaced.

In addition, a 200,000-copy actual copying test was conducted in the same manner as in Example 6 except that the fiber density of the brush was set to 11.6 × 10 ² f / cm ² .

At this time, the effective driving torque T of the brush is
It was 2.10 kgf · cm.

The test results are shown in Table 1.

[0107]

[Table 1]

As shown in Examples 1 to 7, in the present invention,
Good image quality is obtained from the initial stage to 200,000 copies.

On the other hand, in Comparative Examples 1 to 5, it is found that the image quality deteriorates due to repeated use and there is a problem.

[0110]

According to the present invention, it is possible to develop a cleaning method having excellent cleaning performance which does not cause image unevenness, black streaks, and fog, and an image forming method capable of obtaining a stable copy image with high image quality for a long period of time. A device can be provided.

[Brief description of drawings]

FIG. 1 is a schematic view showing a configuration of an organic photoconductor, a brush roller and an elastic rubber blade according to the present invention.

FIG. 2 is a schematic diagram of an apparatus used for torque measurement.

FIG. 3 is a layer configuration diagram of a photoreceptor according to the present invention.

[Explanation of symbols]

 1 Organic Photoreceptor 2 Cylindrical Brush Support 3 Adhesive Layer 4 Brush Roller 5 Elastic Rubber Blade 6 Support Member 11 Conductive Support 12 Charge Generation Layer 13 Charge Transport Layer 14, 14 ′, 14 ″ Photosensitive Layer 15 Intermediate Layer 16 Charge generation material 17 Charge transport material

Claims (3)

[Claims] 1. An image forming method comprising a step of cleaning the toner remaining on the photosensitive member with a brush roller and an elastic rubber blade after transferring the toner image on the moving organic photosensitive member to a recording material. The resin constituting the outermost surface layer of the organic photoreceptor has a viscosity average molecular weight of 5 × 10 ⁴
Above, and the effective driving torque T of the brush roller specified below is 0.1 kgf · cm or more, 2.0 k
An image forming method characterized by being gf · cm or less. Effective drive torque T = T ₁ −T ₂ T ₁ : Drive torque of brush roller when brush roller and photoconductor are in contact T ₂ : Drive torque of brush roller when brush roller and photoconductor are not in contact 2. The image forming method according to claim 1, wherein the resin is a polycarbonate resin. 3. An image forming apparatus having a mechanism for cleaning the toner remaining on the photoconductor with a brush roller and an elastic rubber blade after the toner image on the moving organic photoconductor is transferred to a recording material. The resin constituting the outermost surface layer of the organic photoreceptor has a viscosity average molecular weight of 5 × 10 ⁴
Above, and the effective driving torque T of the brush roller specified below is 0.1 kgf · cm or more, 2.0 k
An image forming apparatus having a gf · cm or less. Effective drive torque T = T ₁ −T ₂ T ₁ : Drive torque of brush roller when brush roller and photoconductor are in contact T ₂ : Drive torque of brush roller when brush roller and photoconductor are not in contact