JPH11305474A - Seamless photoreceptor belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a seamless photoreceptor belt with an excellent image and durability by applying a photoreceptor layer on a seamless belt equipped with a surface layer controlled to some fixed resistance dispersion and some fixed resistance variation in some specified semiconductor area. SOLUTION: This seamless belt 1 is obtained by applying the photoreceptor layer on the surface layer of the seamless belt 1 being the base substance of the photoreceptor. As for the average value of an electric resistance value in the surface layer of the seamless belt 1; volume resistivity is within a range being >=1×10<0> Ω.cm and <=1×10<10> Ω.cm and surface resistivity is within a range being >=1×10<0> Ω/(square) and <=1×10<0> Ω/(square), and the dispersion expressed by the maximum value/minimum value of the volume resistivity and the surface resistivity at the respective parts of the seamless belt is within a range being 1 to 100, tesistance change expressed by the maximum value/ minimum value in optional 20 mm on the seamless belt is within 8, and the contact angle of the surface of the seamless belt with water is <=105 deg..

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a seamless photosensitive belt, and more particularly, to a seamless photosensitive belt used in electrophotography.

[0002]

2. Description of the Related Art An endless belt is frequently used in a photosensitive device such as an electrophotographic copying machine. FIG. 1 is a structural explanatory view schematically showing the structure of a full-color photosensitive device.
In this type of full-color photosensitive device, the photosensitive belt 1
An intermediate transfer member 6 is provided.

Around the photoreceptor belt 1, a charger 2, an exposure optical system 3 using a semiconductor laser or the like as a light source, developing devices 4a to 4d containing toner, and a cleaner 5 for removing residual toner. And an electrophotographic process unit comprising the same. The photoreceptor belt 1 is stretched over conveying rollers 7, 8, and 9 and moves in the direction of the arrow.

Next, the operation of the full-color photosensitive device will be described. First, the surface of the photosensitive belt 1 rotating in the direction of arrow A is uniformly charged by the charger 2. Next, an electrostatic latent image corresponding to an image obtained by an image reading device (not shown) is
Form on top. The electrostatic latent image is developed into a toner image by the developing device 4. This toner image is electrostatically transferred to the intermediate transfer body 6 by the electrostatic transfer machine 13 and transferred to the recording paper 14 between the transport roller 12 and the pressing roller 15.

In such a conventional photosensitive apparatus such as an electrophotographic copying machine, the following two photosensitive belts have been put to practical use. One is a photoreceptor belt in which a photosensitive layer is formed by coating a photosensitive layer on a resin film (photoreceptor substrate) on which aluminum is deposited and then joining both ends of the film to form an endless belt. A photosensitive layer is formed by coating a photosensitive layer on a seamless conductive substrate (photoreceptor substrate) using cast nickel.

However, in the former case, since the seam portion becomes an image defect, a system for detecting the position of the photoreceptor belt so that the image does not ride on the seam portion is required, so that not only the machine cost is increased but also the seam strength is reduced. There was also a problem. On the other hand, the latter photoreceptor belt is poor in flexibility and has a problem in practicality because the base is made of metal.

Therefore, development of a photoreceptor belt using a resinous seamless belt as a photoreceptor base has been desired, and the following has been proposed. A seamless belt obtained by casting a polyimide solution on a rotating drum and curing reaction is produced as a photoreceptor substrate, and then a conductive layer, a photosensitive layer, etc. are applied to the seamless belt. A seamless belt is formed by extruding a seamless belt as a photoconductor substrate, and coating a conductive layer, a photosensitive layer, and the like thereon, and a seamless conductive belt obtained by casting or centrifugally forming a polyimide dispersion mixed with a conductive filler ( A conductive layer or a photosensitive layer coated on a photosensitive body), a thermoplastic resin composition containing a conductive filler such as carbon in a specific thermoplastic resin composition such as polyester or polycarbonate. A proposal has been made of an extruded seamless conductive belt (photoreceptor substrate) formed by applying a conductive layer, a photosensitive layer, and the like. There.

However, the photoreceptor belts described in the above paragraphs require a step of applying a conductive layer to the seamless belt, which is problematic in that the steps are complicated and the productivity is inferior, and in the step of applying the conductive layer. There is a problem that the conductivity varies. Regarding the photoreceptor belt described in the above section, probably because the conductive filler is dispersed in the solvent, carbon moves in the solvent, it is difficult to control the carbon dispersion uniformly, and the electric resistance varies. Occurs.

Therefore, when a photosensitive layer is applied to the seamless belt and used as a photosensitive belt, there is a problem that image unevenness occurs. Further, since the seamless belt is made using a solvent, the residual solvent may attack the photosensitive layer and cause an image abnormality. In addition, there is a problem that productivity is inferior because production is performed in a batch system.

The above item is excellent in productivity due to continuous molding. However, it is difficult to mix carbon or the like with an insulating resin in order to form a conductive region, or it is difficult for carbon to be uniformly dispersed, In addition to the case where unevenness occurs due to irregularities in the image, an unknown cause of image unevenness occurs, and it is necessary to add a large amount of carbon to express conductivity and the belt is easily broken and used as a photoreceptor belt Had not been reached.

[0011]

The inventors of the present invention have conducted intensive studies and have found that even if the electric resistance of the photoreceptor substrate is not in the conductive region, there is a certain resistance variation in a specific semiconductive region. It has been found that excellent images and durability can be obtained with a seamless belt having a surface layer controlled to a constant resistance change amount, that is, a seamless photosensitive belt having a structure in which a photosensitive layer is coated on a photosensitive substrate. That is, it has been found that a clear image can be obtained by using a photoconductor substrate having a local resistance change rate within a certain range.

Further, the seamless photoreceptor belt according to the present invention, in which a photosensitive layer is coated on a seamless belt having electric resistance, does not require a conductive region, so that it is not necessary to mix additional components more than necessary. It has been found to have excellent durability.

[0013]

SUMMARY OF THE INVENTION The present invention is a seamless photoreceptor belt, and is configured as follows to solve the above-mentioned technical problem. That is, the present invention is a seamless photoreceptor belt obtained by applying a photosensitive layer on a surface layer of a seamless belt serving as a photoreceptor substrate, wherein the average value of the electric resistance value in the surface layer of the seamless belt is 1 × 10 ⁰ Ω in resistivity. cm or more, 1
× 10 ¹⁰ Ω. cm or less, 1 × 10 ⁰ Ω / □ in surface resistivity
Above, 1 × is in the range of 10 ¹⁰ Omega / □ or less, in the range variation of 1 to 100 times represented by the maximum value / minimum value of the volume resistivity and surface resistivity in the seamless belt each section, and wherein It is characterized in that the resistivity change represented by the maximum value / minimum value between any 20 mm on the seamless belt is within 8 and the contact angle of the seamless belt surface with water is 105 degrees or less.

In such a seamless photoreceptor belt, the seamless belt is preferably formed by extruding a thermoplastic resin composition containing a conductive filler from an annular die. Further, the seamless belt preferably has at least one layer in which acetylene black is mixed in a range of 10% by weight or more and 20% by weight or less with a thermoplastic resin. Further, the seamless belt preferably has a heat shrinkage at 125 ° C. of 5% or less. Further, it is preferable that the variation in the inner diameter of the seamless belt is within ± 0.3% and the variation in the thickness is within ± 5%. In addition, the ten-point average roughness of the outer surface of the belt in this seamless belt is 3 μm or less. It is also preferred.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The seamless photoreceptor belt of the present invention will be described below in more detail with reference to specific examples. (1) Configuration of seamless photoreceptor belt: When the seamless photoreceptor belt of the present invention is used as an electrophotographic photoreceptor belt, the layer configuration of the seamless photoreceptor belt is proposed as an existing organic electrophotographic photoreceptor shown below. Can be used.

That is, the seamless photoreceptor belt of the present invention is a single layer in which a charge generating agent and a charge transporting agent are combined on the outer peripheral surface of a conductive seamless belt (photoreceptor base) controlled to a specific range of electric resistance. One coated with a photosensitive layer,
A layer in which a charge generation layer is applied on the outer peripheral surface of the conductive seamless belt and then a charge transfer layer is sequentially applied to form a laminated photosensitive layer may be used.

Further, a protective layer is applied to the outermost layer for the purpose of preventing the surface of the photosensitive layer from being damaged and preventing the toner from being fixedly deposited on the film. In order to prevent migration, the undercoat layer and the blocking layer may be provided between the conductive seamless belt and the photosensitive layer.

(2) Electric resistance of the seamless belt (photosensitive body): The electrical properties of the photosensitive body constituting the seamless photosensitive belt, that is, the seamless belt, have a volume resistivity of 1
× 10 ⁰ from 1 × ¹⁰ 10 Ω. cm, surface resistivity 1 × 1
It must be in the range of ⁰ to 1 × 10 ¹⁰ Ω / □, and its variation must be within 100 times. Preferably, the volume resistivity is from 1 × 10 ² to 1 × 10 ⁹ Ω. cm, the surface resistivity is in the range of 1 × 10 ² to 1 × 10 ⁹ Ω / □, and the variation is within 20 times, more preferably within 10 times.

If the electric resistance value is lower than this, it is necessary to add a large amount of a conductive substance, so that not only the moldability of the seamless belt is significantly impaired, but also the seamless belt becomes brittle and the mechanical strength decreases. If the electric resistance value is higher than this, it does not play a role as a conductor, and the charging becomes unstable or the photoresponse of the photoreceptor decreases. Therefore, as described above, the electric resistance value of the photoconductor substrate must be controlled in a certain range of the semiconductive region.

If the rate of change in resistance is not a certain rate of change, the once-charged charge moves to a lower resistance, which affects the image. Therefore, it is important that the rate of change between the volume resistivity and the surface resistivity is not more than 8 as the maximum value / minimum value between any 20 mm on the belt. In particular, the volume resistivity is 1 × 10 ² to 1 × 10 ⁹ Ω. cm, the surface resistivity is in the range of 1 × 10 ² to 1 × 10 ⁹ Ω / □, and the change in volume resistivity and surface resistivity
A seamless photoreceptor belt obtained by coating a photosensitive layer or the like on a seamless belt having a conductive surface layer having a maximum value / minimum value of 6 or less between 0 mm is preferable.

(3) Accuracy of the inner diameter of the seamless belt (photosensitive body): The seamless belt, which is the photosensitive body constituting the seamless photosensitive belt, is used as the innermost component, so that the seamless belt is seamless. The inner diameter accuracy of the belt is particularly important. That is, if the inner diameter accuracy of the seamless belt is not within a certain range, the meandering of the belt may be caused to cause a contact between the belt and the end of the roller, or a meandering preventing rubber guide attached to both ends of the belt. The belt becomes extremely stressed and breaks easily. The variation of the inner diameter in the width direction of the seamless belt is preferably within ± 0.3%, and more preferably the inner diameter accuracy is within ± 0.1%.

(4) Manufacturing method of a seamless belt (photosensitive body): A method of manufacturing a seamless belt, which is a photosensitive body constituting a seamless photosensitive belt, is not particularly limited, and any known method can be used, and particularly preferred. As a method for manufacturing a seamless belt, a thermoplastic resin, an elastomer, or the like is melt-extruded into a tube from an annular die attached to the extruder tip, and the outside and / or inside of the tube is cooled to form a seamless tube continuously. Is preferred in terms of continuous productivity, uniformity of electric resistance, and uniformity of inner diameter.

The extrusion direction may be either the vertical direction or the horizontal direction, but a vertical downward extrusion method which is not affected by gravity and which can control the inner diameter of the tube with high precision is preferable. Examples of the annular die include a side feed die, a mandrel support die, a crosshead die, an offset die, and the like, and a spiral die in which thickness unevenness and variation in electric resistance hardly occur at a resin merging portion is preferable.

Furthermore, in order to obtain a uniform resistance value, the molten resin is extruded at a constant rate by a gear pump, the temperature in the die and the temperature of the molten resin are controlled uniformly, the temperature in the annular die is made uniform, A divided heater or the like may be provided in the die to independently and independently control the temperature in the die and the temperature of the molten resin. What is important is that the resistance value variation of the seamless belt is controlled within a certain range.

The method of coating a photosensitive layer or the like on such a seamless belt is not particularly limited, but the seamless belt and the photosensitive layer may be extruded in a multilayer structure, or only the seamless belt may be formed by extrusion molding. , A blocking layer, a photosensitive layer, or the like, may be coated by a known coating method such as dip coating, spray coating, or beam coating to form a seamless photoreceptor belt. A seamless photoreceptor belt may be formed by successively superposing and applying a known coating method, such as, for example, without particular limitation.

In consideration of productivity, uniformity of electric resistance, and the like, a method for manufacturing a seamless photosensitive belt is as follows: a seamless belt is formed by extrusion molding, and a blocking layer, a photosensitive layer, and the like are dip-coated, spray-coated, and beam-coated. It is preferable to manufacture by coating by a known coating method such as

(5) Material of Seamless Belt (Photosensitive Material Substrate): The resin composition of the seamless belt applied in the present invention is a thermoplastic resin, and includes a resin containing a conductive filler.

As the thermoplastic resin, ethylene (high density, medium density, low density, linear low density), propylene ethylene block or random copolymer, rubber or latex component such as ethylene-propylene copolymer rubber,
Styrene-butadiene rubber, styrene-butadiene-styrene block copolymer or hydrogenated derivative thereof, polybutadiene, polyisobutylene, polyamide, polyamideimide, polyacetal, polyarylate, polycarbonate, polyphenylene ether, modified polyphenylene ether, polyimide, liquid crystalline polyester, Polyethylene terephthalate, polysulfone, polyether sulfone, polyphenylene sulfide, polybisamide triazole, polybutylene terephthalate, polyether imide, polyether ether ketone, acrylic, polyvinylidene fluoride, polyvinyl fluoride, ethylene tetrafluoroethylene copolymer, polychloro Trifluoroethylene, tetrafluoroethylene hexafluoropropylene copolymer Copolymer, tetrafluoroethylene perfluoroalkyl vinyl ether copolymer, polytetrafluoroethylene, fluororubber, alkyl acrylate copolymer, polyester ester copolymer 000000fd coal, polyether ester copolymer, polyether amide copolymer, An olefin copolymer, a polyurethane copolymer, or a mixture thereof is used.

Particularly preferred resins are polyvinylidene fluoride, polyvinyl fluoride, ethylene tetrafluoroethylene copolymer, polychlorotrifluoroethylene, tetrafluoroethylene hexafluoropropylene copolymer, and tetrafluoroethylene perfluoroalkyl vinyl ether copolymer. Fluororesins and rubbers such as polytetrafluoroethylene and the like are also preferable for preventing contamination from toner and the like, and polycarbonate, polybutylene terephthalate, polyethylene terephthalate, polyester ester copolymers, polyether ester copolymers, etc. The ester-based thermoplastic resin is preferable because the electric resistance value is stable with little change in electric resistance.

The conductive filler is at least one selected from carbon black, graphite, carbon fiber, metal powder, conductive metal oxide, organic metal oxide, organic metal compound, organic metal salt, conductive polymer, and the like. Alternatively, a mixture of several kinds of these is preferable. Among them, carbon black is particularly preferred. As carbon black, acetylene black, furnace black,
There is carbon black such as channel black. Acetylene black excellent in dispersibility is preferable so as not to impair the appearance of the film.

The amount of carbon black varies depending on the type of carbon black. In the case of acetylene black, the amount is preferably 3 to 25% by weight in the thermoplastic resin, and more preferably 10 to 25% by weight in the thermoplastic resin. ~ 20
It is particularly preferred that the composition be blended by weight. In the case of Ketjen Black, the content is preferably 1 to 10% by weight, and may be used in combination with acetylene black. If it is less than the above range, the conductivity is poor, and if it is more than the above range, the appearance of the product is deteriorated and the material strength is unfavorably reduced.

The resin composition may contain various additional components to be added to the usual resin composition as long as the object of the present invention is not hindered. Such components include antioxidants, lubricants, release agents, and the like.

Further, as long as the effects of the present invention are not significantly impaired, the following additional components other than those described above may be further added. Thermoplastic resins, thermosetting resins, as various fillers, for example, calcium carbonate, talc, mica,
Silica, alumina, aluminum hydroxide, magnesium hydroxide, barium sulfate, zinc oxide, zeolite, wollastonite, diatomaceous earth, glass beads, bentonite, montmorillonite, asbestos, hollow glass spheres, graphite, molybdenum disulfide, titanium oxide, Examples include fillers such as aluminum fiber, stainless steel fiber, brass fiber, aluminum powder, wood powder, rice hull, graphite, metal powder, conductive metal oxide, organometallic compound, and organometallic salt.

The additives include, for example, antioxidants (phenol-based, sulfur-based, etc.), lubricants, various organic and inorganic pigments, ultraviolet absorbers, antistatic agents, dispersants, neutralizing agents, foaming agents, and the like. Agents, plasticizers, copper damage inhibitors, crosslinking agents, flowability improvers, and the like.

(6) Outer surface roughness of the seamless belt: The roughness of the seamless belt, which is a photosensitive member substrate, is preferably within 3 μm in terms of a ten-point average roughness. The average particle size of the toner is generally 5 μm to 8 μm, and since the particle size distribution has a wide range, if the ten-point average roughness exceeds 3 μm, the surface after applying the photosensitive layer becomes rough, and the toner having a small particle size may not be obtained. There is a case where the toner is stuck in the minute unevenness of the seamless photoreceptor belt, the toner is fixedly deposited on the film, and the transfer efficiency to paper is deteriorated, and the resistance value is changed, so that the image becomes uneven. Further, the preferable roughness of the seamless belt is within 1 μm in ten-point average roughness.

(7) Thermal Shrinkage of Seamless Belt: The thermal shrinkage at 100 ° C. of the seamless belt, which is a photosensitive member substrate, is preferably 5% or less. In an electrophotographic apparatus, the ambient temperature in the apparatus may locally reach 100 ° C., and if the shrinkage ratio at that time exceeds 5%, the inner diameter of the belt becomes small, and the apparatus is driven by being stretched with two or more rollers. In this case, the tension at both ends of the belt changes due to a temperature difference in the apparatus, and the belt meanders, and the electric resistance changes due to shrinkage. Preferably, the heat shrinkage at 100 ° C. is 3%
It is as follows.

(8) Thickness of the seamless belt: The thickness of the seamless belt, which is a photoreceptor substrate, is 25 to 1,000.
μm or less, more preferably 50 μm or more and 200 μm or less. If it is less than 25 μm, it is unfavorable because it stretches when driven by being stretched with two or more rollers. On the other hand, if the thickness exceeds 1000 μm, the seamless tube becomes hard, does not undergo elastic deformation, is not flexible, and is difficult to be stretched and driven by two or more rollers.

(9) Contact angle: The contact angle of the outer surface of the seamless belt is related to the adhesiveness of the interface between the photosensitive layer and the seamless belt. Preferred is 100-70 degrees.

(10) Reinforcement tape: Further, for the purpose of supplementing the strength of the seamless photoreceptor belt, outer and / or inner ends of both ends of the seamless belt photoreceptor belt are shown in FIGS.
As shown in (2), a configuration in which a reinforcing tape 16 such as PET is attached may be used.

(11) Guide for preventing meandering: In order to prevent meandering of the seamless photoreceptor belt, both ends on the inner side of the seamless photoreceptor belt are made of JI such as urethane or silicon.
A meandering prevention guide 17 having a hardness of 30 to 90 degrees by SA may be provided. In that case, grooves 18 are formed in the transport rollers 7, 8, 9 around which the seamless photoreceptor belt 1 is wound, as shown in FIG. Need to be kept.

(12) Photosensitive layer: The charge generating agent contained in the single-layer type photosensitive layer includes selenium and its alloys, arsenic-selenium, cadmium sulfide, zinc oxide, zinc sulfide, antimony sulfide, Cds-Se and the like. Alloys, oxide-based semiconductors such as titanium oxide, silicon-based materials such as amorphous silicon, other inorganic photoconductive materials,
Various organic pigments and dyes such as phthalocyanine, azo dye, quinacridone, polycyclic quinone, pyrylium salt, perylene, indigo, thioindigo, anthantrone, pyranthrone and cyanine can be used. Among them, metal-free phthalocyanine, copper, indium chloride, gallium chloride, silicon, tin, oxytitanium, zinc, vanadium and other metals, or oxides, chlorides, hydroxide-coordinated phthalocyanines, monoazo, bisazo, trisazo ,
Azo pigments such as polyazos are desirable. These charge generating agents can be used alone or in combination of two or more.

As the charge transporting agent contained in the single-layer type photosensitive layer, polyvinyl carbazole, polyvinyl pyrene,
Polymer compounds such as polyacenaphthylene and polyvinylanthracene, or various pyrazoline derivatives, carbazole derivatives, oxazole derivatives, hydrazone derivatives, stilbene derivatives, arylamine derivatives, oxadiazole derivatives, thiazole derivatives, thiadiazole derivatives, triazole derivatives, imidazole derivatives And low molecular compounds such as imidazolone derivatives, imidazolidine derivatives, styryl compounds, benzothiazole derivatives, benzimidazoles, acridine derivatives, and phenazine derivatives.

In addition to the above-described hole transport type charge transport agents, electron transport agents such as benzoquinone derivatives, naphthoquinone derivatives, anthraquinone derivatives, diphenoquinone derivatives, and fluorenone derivatives are also used as necessary. These charge transporting agents are used in consideration of the combination with the charge generating agent, the polarity and the like.
Species are used or two or more are used in combination.

A charge generating agent contained in the single-layer type photosensitive layer,
When the charge transporting agent has poor film-forming ability, it may be formed using a binder polymer. In this case, the charge generation layer can be obtained by applying and drying a coating solution obtained by dissolving or dispersing these substances and a binder polymer in a solvent.

As the binder, for example, butadiene,
Styrene, vinyl acetate, vinyl chloride, acrylic acid ester, methacrylic acid ester, vinyl alcohol, polymers and copolymers of vinyl compounds such as ethyl vinyl ether, polyvinyl acetal, polycarbonate, polyester, polyamide, polyurethane, cellulose ether, phenoxy resin, Silicon resin, epoxy resin and the like can be mentioned. These can be used after being crosslinked by heat, light or the like using an appropriate curing agent or the like. These binders can be used alone or in combination of two or more.

When the photosensitive layer has a single-layer structure, a coating solution in which additives other than the following charge generating agent, charge transporting agent, and binder polymer are dissolved and dispersed in a solvent is applied on a substrate by the same method. Thereby, a photosensitive layer is obtained.

Solvents and dispersion media used for coating 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,
Examples include dichloromethane, tetrahydrofuran, dioxane, methyl alcohol, ethyl alcohol, isopropyl alcohol, ethyl acetate, butyl acetate, dimethyl sulfoxide, and methyl cellosolve. One of these solvents may be used alone, or two or more thereof may be used as a mixed solvent.

On the other hand, when the photosensitive layer has a laminated structure,
As the charge generating agent in the charge generating layer, the same charge generating agent as that of the single layer type can be used, but a binder polymer may be added. Generally, for 100 parts by weight of the charge generating agent,
5 to 500 parts by weight, preferably 20 to 300 parts by weight, of binder polymer are used.

The charge generating agent is usually dispersed and dissolved in an appropriate dispersing medium using a ball mill, an ultrasonic disperser, a paint shaker, an attritor, a sand grinder or the like, and if necessary, a binder resin is added thereto to prepare a coating solution. After adjusting, this coating solution is applied by a coating method such as dipping method, spray method, bar coater method, blade method, roll coater method, wire bar coating method, knife coater coating method, etc.
dry. Further, the charge generation layer may be formed by depositing the above-mentioned charge generation agent by a vapor deposition method such as vapor deposition or sputtering. The thickness of the charge generation layer is preferably in the range of 0.01 to 5 μm, and more preferably 0.05 to 2 μm.

In the charge transporting layer, the same charge transporting agent as that of the single layer type can be used, but a binder polymer may be added, and the ratio thereof is not particularly limited. 10 to 5 parts
00 parts by weight, preferably 30 to 300 parts by weight, of binder polymer are used.

The charge transport layer is mixed with the above polymer having excellent performance as a binder, dissolved in a suitable solvent together with a charge transport agent, and the obtained coating solution is applied in the same manner as the charge generation layer. Thus, it can be manufactured. The thickness of the charge transport layer is usually 10 μm to 50 μm.
m, preferably in the range of 13 μm to 35 μm.

In either case of a single layer or a laminate, an electron withdrawing compound or a plasticizer, a pigment or other additives may be added as required. Examples of the electron-withdrawing compound include cyano compounds such as tetracyanoquinodimethane, dicyanoquinomethane, and aromatic esters having a dicyanoquinovinyl group; nitro compounds such as 2,4,6-trinitrofluorenone; and condensation of perylene and the like. Polycyclic aromatic compounds; diphenoquinone derivatives; quinones; aldehydes;
Ketones; esters; acid anhydrides; phthalides; substituted and unsubstituted metal complexes of salicylic acid; substituted and unsubstituted metal salts of salicylic acid; metal complexes of aromatic carboxylic acids; metal salts of aromatic carboxylic acids.

Preferably, cyano compounds, nitro compounds, condensed polycyclic aromatic compounds, diphenoquinone derivatives, metal complexes of substituted and unsubstituted salicylic acids, metal salts of substituted and unsubstituted salicylic acids; metal complexes of aromatic carboxylic acids; It is preferred to use metal salts of carboxylic acids.

Further, in either case of a single layer or a laminate, the photosensitive layer of the electrophotographic photosensitive member of the present invention improves film forming property, flexibility, coating property, mechanical strength, film forming property, durability and the like. For this purpose, well-known plasticizers, antioxidants, ultraviolet absorbers, and leveling agents may be contained.

In either case of a single layer or a laminate, the photoreceptor thus formed may have an undercoat layer, a blocking layer, a surface protective layer and the like, if necessary. No. The undercoat layer is usually used between the photosensitive layer and the conductive seamless belt, and a commonly used known layer can be used. As the undercoat layer, inorganic fine particles such as titanium oxide, aluminum oxide, zirconia, and silicon oxide, organic fine particles, polyamide resin, phenol resin, melamine resin, casein, polyurethane resin, epoxy resin, cellulose, nitrocellulose, polyvinyl alcohol, polyvinyl butyral A component such as a resin can be used. These fine particles and resin can be used alone or in combination of two or more. The thickness is usually 0.01 to 50 μm, preferably 0.01 to 10 μm.

A known blocking layer may be provided between the photosensitive layer and the conductive seamless belt. And
When a surface protective layer is provided on the present photoreceptor, the thickness of the protective layer is 0.1 mm.
01 to 20 μm is possible, preferably 0.1 to 10
μm. For the protective layer, the binder described above can be used, but the charge generator, the charge transport agent, the additive agent,
A conductive material such as a metal and a metal oxide may be contained.

(13) Electrophotographic apparatus: The electrophotographic photoreceptor thus obtained is a seamless photoreceptor belt from which excellent durability and an image can be obtained.
It is suitable for the field of electrophotography such as a fax machine and a plate making machine.

In using the seamless photoreceptor belt of the present invention as an electrophotographic photoreceptor, a charger is a corona charger such as a corotron or a scorotron, a charging roll,
A contact charger such as a charging brush is used. Exposure is by halogen lamp, fluorescent lamp, laser (semiconductor, He-N
e), using an LED, a photoconductor internal exposure system, or the like. For the development process, a dry development system such as a cascade development, a one-component insulation toner development, a one-component conductive toner development, a two-component magnetic brush development, a wet development system, or the like is used.

In the transfer step, an electrostatic transfer method such as corona transfer, roller transfer, belt transfer, pressure transfer method, and adhesive transfer method are used. For fixing, heat roller fixing, flash fixing, oven fixing, pressure fixing and the like are used. For cleaning, a brush cleaner, a magnetic brush cleaner, an electrostatic brush cleaner, a magnetic roller cleaner, a blade cleaner, and the like are used.

[0060]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.
It is not limited to these. In the examples, “parts” means “parts by weight”. The materials used in the preparation of the photoreceptor substrate in Examples and Comparative Examples are as follows. 1. ETFF (Ethylene tetrafluoroethylene copolymer, manufactured by Asahi Glass Co., Ltd., trade name “AFLON COP C55A
P ") 2. 2. PBT (polybutylene terephthalate, manufactured by Mitsubishi Engineering-Plastics Corporation, trade name "Novadol 5020") PC (polycarbonate, manufactured by Mitsubishi Engineering-Plastics Corporation, trade name "Iupilon E200"
0 ") 4. TPEE (Thermoplastic polyester elastomer, manufactured by Toyobo Co., Ltd., product name "Perprenlo P150
B ") 5. Acetylene black (Denka Black, manufactured by Denki Kagaku Co., Ltd.)

Experiments and evaluation methods of the photoreceptor substrate in Examples and Comparative Examples are as follows. 1. Surface specific resistance (Ω / □) Using a resistance meter Hiresta HA probe (manufactured by Dia Instruments), measurement was performed at a measuring voltage of 500 V and a measuring time of 10 seconds at a pitch of 10 mm in the circumferential direction of the tube. 2. Volume specific resistance (Ω · cm) Using a resistance meter Hiresta HRS probe (manufactured by Dia Instruments), measurement was performed at a measuring voltage of 100 V and a measuring time of 10 seconds at a pitch of 10 mm in the circumferential direction of the tube. 3. Inner diameter accuracy Cut a seamless tube with a three-dimensional dimension measuring instrument, measure the circumferential dimensions of both ends and the center of the tube, and if it is within ± 0.5% of the average inner diameter, ○, exceed 0.5% The case was evaluated as x. 4. Outer surface roughness "Surfacecom 5" manufactured by Tokyo Seimitsu Co., Ltd.
70A ", the ten-point average roughness of the outer surface of the tube was measured. 5. Heat shrinkage After heating at 100 ° C. for 1 hour, the shrinkage when left at room temperature was determined.

Hereinafter, the seamless photoreceptor belt of the present invention will be further described with reference to specific examples. [Example 1] A 30φ extruder is made of a material containing 65% by weight of PBT, 20% by weight of PC, and 15% by weight of acetylene black. And kneaded into pellets. The obtained pellets are extruded below the annular die in the form of a molten tube using an extruder of 40φ with an annular die. The extruded molten tube was brought into contact with the outer surface of a φ180 cooling mandrel mounted on the same axis as the annular die via a support rod and cooled and solidified to obtain a seamless tube.

Next, the rollers installed in the seamless tube and the rolls installed on the outside,
The seamless tube was taken out while maintaining the cylindrical shape, and cut in the width direction to obtain a seamless photoreceptor substrate.
The results are as shown in Table 1.

A photosensitive layer A was formed on the seamless photoreceptor substrate, that is, a seamless belt as follows. (Preparation of Photosensitive Layer A) 10 parts of an azo compound having the following structure was added to 150 parts of 4-methoxy-4-methylpentanone-2.
In addition to the above, pulverization and dispersion treatment was performed with a sand glide mill. The pigment dispersion obtained here was treated with polyvinyl butyral (trade name # 6000-C, manufactured by Denki Kagaku Kogyo KK).
100 parts of a 1,2-dimethoxyethane solution and 100 parts of a 5% dimethoxyethane solution of a phenoxy resin (PKHH, manufactured by Union Carbide Co., Ltd.)
Finally, a dispersion having a solid concentration of 4.0% was prepared.

[0065]

Embedded image

The charge-generating layer solution, ie, the photosensitive layer solution, is coated on a seamless belt using a ring coater so that the dry film thickness becomes 0.4 g / m ² (about 0.4 μm). Layers were provided.

(Preparation of Charge Transfer Layer) Next, 95 parts of the following charge transport agent was provided on the charge generation layer:

Embedded image 1.5 parts of the following cyano compound as an electron-withdrawing compound

Embedded image And 100 parts of a polycarbonate resin (manufactured by Mitsubishi Gas Chemical Co., Ltd., trade name: Z-200) dissolved in a mixed solvent of tetrahydrofuran and dioxane.
After drying at 125 ° C. for 25 minutes, a charge transfer layer was provided so that the dry film thickness became 21 μm. Thus, an electrophotographic photosensitive member is obtained. The obtained electrophotographic photosensitive member was installed in the apparatus shown in FIG. 1 and the image was evaluated. As a result, no image unevenness occurred.

Example 2 As a material, 65% by weight of PC was used.
A seamless photoreceptor substrate was obtained in the same manner as in Example 1, except that a material containing 20% by weight of PBT and 15% by weight of acetylene black was used. Table 1 shows the results. A photosensitive layer similar to that of Example 1 was formed on this seamless belt, and the obtained electrophotographic photosensitive member was evaluated for images in the same manner as in Example 1. As a result, no image unevenness occurred.

Example 3 A seamless photoreceptor substrate was obtained in the same manner as in Example 1, except that a material mixed with 84% by weight of ETFE and 16% by weight of acetylene black was used as the material. Table 1 shows the results. A photosensitive layer similar to that of Example 1 was formed on this seamless belt, and the obtained electrophotographic photosensitive member was evaluated for images in the same manner as in Example 1. As a result, no image unevenness occurred.

Example 4 A seamless photoreceptor substrate was obtained in the same manner as in Example 1 except that a material prepared by mixing 84% by weight of a thermoplastic polyester elastomer (TPEE) and 16% by weight of acetylene black was used. Table 1 shows the results. Example 1 on this seamless belt
A photosensitive layer similar to the above was formed, and the obtained electrophotographic photoreceptor was evaluated for an image in the same manner as in Example 1. As a result, a slight image unevenness having a width of 1 mm occurred, but was at a practical level.

Example 5 As a material, 85% by weight of PC was used.
A seamless photoreceptor substrate was obtained in the same manner as in Example 1, except that a material mixed with 15% by weight of acetylene black was used. Table 1 shows the results. A photosensitive layer similar to that of Example 1 was formed on the seamless belt, and the obtained electrophotographic photoreceptor was evaluated for images in the same manner as in Example 1. As a result, slight image unevenness having a width of 2 mm was found. However, it was at a practical level.

Example 6 A photosensitive layer B was formed on the seamless photosensitive member substrate of Example 1 as follows. (Preparation of photosensitive layer B) 10 parts of oxytitanium phthalocyanine exhibiting a powder X-ray diffraction pattern by CuKα, polyvinyl butyral (trade name # 6, manufactured by Denki Igigaku Kogyo KK)
000-C) was added to 5 parts of 500 parts of 1,2-dimethoxyethane, and the mixture was pulverized and dispersed by a sand grind mill.

The dispersion was dried on a seamless belt using a ring coater in the same manner as in Example 1.
A charge generation layer, that is, a photosensitive layer was provided so as to have a thickness of 0.3 g / m ² (about 0.3 μm). (Preparation of Charge Transfer Layer) Next, on this charge generation layer, 56 parts of a hydrazone compound shown below,

Embedded image 14 parts of the following hydrazone compound

Embedded image And 1.5 parts of the following cyanide compound

Embedded image A solution obtained by dissolving 100 parts of a polycarbonate resin (trade name: Z-200, manufactured by Mitsubishi Gas Chemical Co., Ltd.) in a mixed solvent of tetrahydrofuran and dioxane is applied in the same manner, and dried at 125 ° C. for 25 minutes to obtain a dry film. The charge transport layer was provided so as to have a thickness of 17 μm. The electrophotographic photoreceptor thus obtained was set in the apparatus shown in FIG. 1, and the image was evaluated. As a result, no image unevenness occurred.

Comparative Example 1 A seamless photoreceptor substrate was obtained in the same manner as in Example 1, except that 70 wt% of ETFE, 15 wt% of PC and 15 wt% of acetylene black were used as materials. Table 1 shows the results. A photosensitive layer similar to that of Example 1 was formed on this seamless belt, and the obtained electrophotographic photoreceptor was evaluated for images in the same manner as in Example 1. An image unevenness having a width of 20 mm occurred only in a portion where the image was formed.

Comparative Example 2 PC was 85% by weight as a material.
A seamless photoreceptor substrate was obtained in the same manner as in Example 1, except that a material mixed with 15% by weight of acetylene black was used. However, air was partially blown to the annular die for the purpose of increasing the resistance change rate. Table 1 shows the results.

A photosensitive layer similar to that in Example 6 was formed on a seamless belt, and the obtained electrophotographic photosensitive member was evaluated for images in the same manner as in Example 1. As a result, a portion where the resistance was locally changed was obtained. An image unevenness having a width of 20 mm occurred only in a portion corresponding to.

[0077]

[Table 1]

[0078]

As described above, according to the seamless photoreceptor belt of the present invention, a seamless photoreceptor is obtained by coating a photosensitive layer on a seamless belt which is a photoreceptor substrate having a specific electric resistance value. The belt has excellent durability, and a clear image can be obtained by using the belt in an electrophotographic copying machine, a laser beam printer, or the like.

[Brief description of the drawings]

FIG. 1 is an explanatory view schematically showing a main part of an electrophotographic copying machine incorporating a seamless photosensitive belt of the present invention.

FIG. 2 is a perspective view schematically showing a seamless photoreceptor belt of the present invention.

FIG. 3 is a perspective view of the seamless photoreceptor belt shown in FIG.
It is sectional drawing cut | disconnected and shown along 3 lines.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Seamless photoreceptor 2 Charger 3 Exposure optical system 4a-4d Developing device 5 Cleaner 6 Intermediate transfer member 7-12 Conveyance roller 13 Electrostatic transfer part 14 Recording paper 15 Press roller 16 Reinforcement tape 17 Meandering prevention guide 18 Meandering prevention guide Groove for engagement

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Shinichi Suzuki 1000 Kamoshita-cho, Aoba-ku, Yokohama-shi, Kanagawa Pref.

Claims (6)

[Claims] 1. A seamless photoreceptor belt obtained by applying a photosensitive layer on a surface layer of a seamless belt serving as a photoreceptor substrate, wherein the average value of the electric resistance value in the surface layer of the seamless belt is a volume. 1 × 10 ⁰ Ω in resistivity. cm or more, 1 × 1
0 ¹⁰ Ω. cm or less, and the surface resistivity is in the range of 1 × 10 ⁰ Ω / □ or more and 1 × 10 ¹⁰ Ω / □ or less, and is expressed by the maximum value / minimum value of the volume resistivity and the surface resistivity in each part of the seamless belt. And the contact angle of the surface of the seamless belt with water is within 8 within a range of 1 to 100 times, and a change in resistivity represented by a maximum value / minimum value between arbitrary 20 mm on the seamless belt is within 8. The seamless photoreceptor belt has a temperature of 105 degrees or less. 2. The seamless photoreceptor belt according to claim 1, wherein the seamless belt is formed by extruding a thermoplastic resin composition containing a conductive filler from an annular die. 3. The seamless belt has a thermoplastic resin containing 10% by weight of acetylene black as a conductive filler.
3. The seamless photoreceptor belt according to claim 1, wherein the seamless photoreceptor belt has at least one layer blended at a ratio of not less than 20% by weight. 4. The seamless photosensitive belt according to claim 1, wherein the seamless belt has a heat shrinkage at 100 ° C. of 5% or less. 5. The seamless belt according to claim 1, wherein the variation of the inner diameter in the longitudinal direction is within ± 0.3% and the variation in thickness is within ± 5% with respect to the average value. 5. The seamless photoreceptor belt according to any one of 4. 6. The seamless photoreceptor belt according to claim 1, wherein the seamless belt has a ten-point average roughness on the outer surface of the substrate of 3 μm or less.