JPH01211768A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To improve chargeability of an electrophotographic sensitive body, to reduce relative humidity at high temp. and under high humidity, and to prevent dewing of the photosensitive body at low temp. by incorporating a magnetic body which causes magnetic loss generating heat by absorbing energy of high frequency magnetic field, into an electroconductive substrate and/or the photosensitive layer. CONSTITUTION:A magnetic body is incorporated which causes magnetic loss generating heat by absorbing energy of high frequency magnetic field, into an electroconductive substrate 11 and/or a photosensitive layer 15. By using thus the magnetic body for a heat-source of the photosensitive body in an electroconductive substrate 11, the photosensitive body reaches a set temp. in a short time and the temp. distribution of the photosensitive body is made uniform, thus effective heating is possible. By this constitution, the chargeability of an org. photosensitive body is improved, relative humidity of the atmosphere of the photosensitive body is reduced even at high temp. and under high humidity, and dewing of the photosensitive body at low temp. is prevented.

Description

[Detailed description of the invention] 〔Technical field〕 The present invention relates to improvements in electrophotographic photoreceptors.

[Prior art]

In recent years, photoreceptors used in electrophotographic copying machines have begun to be made of organic photosensitive materials, which have the advantages of low cost, productivity, and non-polluting properties.

Organic electrophotographic photoreceptors include photoconductive resins such as polyvinylcarbazole (PVK), and PVK-TNF.
(2,4,71-linitrofluorenone), a pigment-dispersed type such as a phthalocyanine binder, and a functionally separated photoreceptor using a combination of a charge-generating substance and a charge-transporting substance. is known, and in particular, functionally separated photoreceptors are attracting attention.

When such an organic photoreceptor is applied to the Carlson process, it has low chargeability and poor charge retention (high dark decay), and these characteristics deteriorate significantly with repeated use, causing problems such as It has the drawbacks of density unevenness, fog, and background smearing in the case of reverse development.

That is, the chargeability of organic photoreceptors decreases due to pre-exposure fatigue. This pre-exposure fatigue is mainly caused by light absorbed by the charge-generating material, so the longer the charges generated by light absorption remain in the photoconductor in a mobile state, the more the number of charges increases. It is thought that the lower the chargeability becomes, the more the chargeability decreases due to pre-exposure fatigue. In other words, even if a charging operation is performed while the charge generated by light absorption remains, the surface charge will be neutralized by the movement of the remaining carriers, so the surface potential will increase until the residual charge is consumed. do not. Therefore, the increase in surface potential is delayed by the amount of pre-exposure fatigue, and the apparent charge level 4 becomes lower.

As a method to improve these drawbacks, an inorganic material such as 5iO1AQ, 03 is deposited between the support and the charge generation layer by vapor deposition,
Methods such as sputtering and anodic oxidation are known, and it is also known to include Al2203 in the charge generation layer (Japanese Unexamined Patent Publication No. 142354/1982), and also to include metal powder in the charge generation layer. (Japanese Unexamined Patent Publication No. 60-214364).

In addition, polyamide resin (Japanese Unexamined Patent Publication No. 58-30
No. 757, JP-A No. 58-98739), alcohol-soluble nylon resin (JP-A No. 60-196766)
No. 1, water-soluble polyvinyl butyral resin (Unexamined Japanese Patent Publication No. 6
0-232553) and polyvinyl butyral resin (Japanese Unexamined Patent Publication No. 106549/1982).

However, with regard to the deterioration of chargeability and charge retention due to repeated use, sufficient photoreceptors have not been obtained by means of improving the photoreceptor side.

JP-A No. 51-111338 discloses that when an As2Se3 photoreceptor is maintained at a temperature 10 to 30% higher than room temperature and not exceeding 40°C, the rate of fatigue (dark decay) is slowed down. I'm there.

On the other hand, in the operating environment of a copying apparatus, under high temperature and high humidity conditions, image blurring and image distortion occur, and at low temperatures, there are problems such as dew condensation on the photoreceptor and scumming.

Regarding this environmental dependence, JP-A-61-7843 discloses that the relative humidity of the photoreceptor under high temperature and high humidity can be reduced by heating the support of the photoreceptor layer at a relatively low temperature using a planar heating element. , JP-A-62-121483 discloses a method of blowing hot or cold air onto a photoreceptor, which is a method that can prevent dew condensation on the photoreceptor at low temperatures and prevent deterioration of the photoreceptor at high temperatures. is disclosed.

However, when a photoreceptor (or photosensitive layer) is heated using the above method, it takes a long time to reach a predetermined temperature after heating is started, the heat generation is not uniform and the temperature distribution is uneven, and the heating efficiency is However, there are also problems such as not being good.

〔the purpose〕

The present invention provides an electrophotographic photoreceptor that can improve the charging property of the photoreceptor, reduce relative humidity under high temperature and high humidity conditions, and prevent dew condensation on the photoreceptor at low temperatures, and a rise-up rate during heating. An object of the present invention is to provide an electrophotographic photoreceptor that exhibits a high speed and uniform heating distribution.

〔composition〕

According to the present invention, in an electrophotographic photoreceptor in which a photosensitive layer is provided on a conductive support, the conductive support and/or the photosensitive layer absorb energy of a high frequency magnetic field and become a source of magnetic loss that generates heat. An electrophotographic photoreceptor characterized by containing a magnetic material is provided.

The present inventors have studied to solve the above-mentioned drawbacks of an electrophotographic photoreceptor in which at least a photosensitive layer is provided on a conductive support. It has been found that a material containing a magnetic material that acts as a source of magnetic loss that absorbs heat and generates heat is suitable for the above purpose.

According to the research conducted by the present inventors, it has been found that the heating temperature is higher than room temperature, preferably higher than 40°C, more preferably higher than 50°C, and a good improvement in charging is achieved. It was found that the rate of improvement was fast. However, when heating at high temperatures, the organic substances in the photosensitive layer may undergo oxidation or other deterioration, and the toner in the developing section may melt or stick. Although there are some differences, it is desirable to perform the heat treatment at a temperature of 150°C or lower, preferably 120°C or lower.

In this case, the magnetic material contained in the conductive support and/or photosensitive layer of the present invention absorbs the energy of the high-frequency magnetic field (including microwave energy, etc.) and generates heat, so it can be used as a heat source. This heat generation can result in hysteresis loss. Moreover, this heat generation is the same development as the temperature rise of the iron core, which causes hysteresis loss. Therefore, here, the imaginary part μ'' of the complex magnetic permeability μ=μ′−5μ″ of the magnetic material
is an important factor for fever.

When such a magnetic material, which absorbs the energy of a high-frequency magnetic field and becomes a source of magnetic loss and generates heat, is used in the conductive support as a heating source for a photoreceptor, the following advantages occur.

■Achieves the set temperature in a short time.

■The temperature distribution of the photoreceptor becomes uniform and effective heating is possible.

■Since no heat-generating wires are used, there is no disconnection, resulting in long life and high reliability.

In the present invention, the heating means may be operated continuously or intermittently.

It is also possible in the present invention to use cooling means.

That is, a photoreceptor heated to a relatively high temperature can be cooled down to a predetermined temperature during use, or can be used simultaneously with a heating means to set a more appropriate operating temperature.

Next, the present invention will be explained using the drawings.

FIG. 1 is a sectional view showing an example of the configuration of a photoreceptor used in the present invention, in which a photoreceptor M15 is provided on a conductive support 11 containing a magnetic material.

FIGS. 2A and 2A are cross-sectional views showing another example of the structure, in which the photosensitive layer is composed of a stack of a charge generation layer 21 and a charge transport layer 23.

FIG. 3 and FIG. 4 are cross-sectional views showing still another example of the structure. Further, in FIG. 4, a protection layer N17 is provided on the photosensitive layer 15. Here, between the photosensitive N15 and the protective layer 17 there is an intermediate Jl (not shown)
It is also possible to provide A typical example of the conductive support 11 containing a magnetic material is shown in FIG. 5a.

Shown in b.

5 and 8 shows an example in which a layer 32 containing a magnetic material is provided on the back surface of a conductive base 31, and the conductive base 31 may be one that exhibits conductivity with a volume resistance of 1010 Ωcm or less;
For example, aluminum, nickel, chromium, nichrome,
Film or cylindrical plastic or paper coated with metals such as copper, silver, gold, platinum, or metal oxides such as tin oxide or indium oxide by vapor deposition or sputtering, or aluminum, aluminum alloy, or nickel. , plates made of stainless steel and the like, 1.
．． 1.1. It is possible to use pipes that have been made into blank pipes by methods such as , extrusion, and drawing, and then surface-treated by cutting, superfinishing, polishing, and the like.

The layer 32 containing a magnetic substance is formed by dispersing particles of a magnetic substance in a suitable binder and coating the conductive substrate 31 with a coating method or the like.
It can be provided on the back side of

Here, as the magnetic material, it is preferable to use a material whose imaginary part μr'' of complex relative magnetic permeability is 0.1 or more, and examples of such magnetic materials include magnetite, Ni-Zn ferrite, N
iFe2O4 ferrite, Mn-Mg ferrite, M
n-Zn ferrite, NiCrZn ferrite, δ-
Examples include hematite, magnetite, ferox spreena, etc.

In addition, binders include polystyrene, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyester, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer,
Polyvinyl acetate, polyvinylidene chloride, polyacrylate resin, pheno-8=oxy resin, polycarbonate, cellulose acetate resin, ethyl cellulose resin, polyvinyl butyral, polyvinyl formal, polyvinyltoluene, poly-N-vinylcarbazole, acrylic resin, silicone @ fat Thermoplastic or thermosetting resins such as epoxy resins, melamine resins, urethane resins, phenolic resins, and alkyd resins are used, and insulating inorganic binders are also suitably used.

In the layer 32 containing such a magnetic material, if the content of the magnetic material is 15% by weight or more, preferably 20% by weight or more, it becomes a good heating source. Furthermore, when the magnetic material is dispersed in the form of powder in a binder, the smaller the particle size of the magnetic powder, the better the heating. The particle size of magnetic powder is 2μm
The thickness is preferably 1 μm or less.

FIG. 5 shows an example in which a conductive layer 33 is provided on a base 34 containing a magnetic material.

The base 34 containing a magnetic substance is a base in which a magnetic substance is mixed and dispersed in a binder, and the above-mentioned materials are used as the magnetic substance.

As a binder, thermoplastic resins such as polystyrene, polyethylene, polyacetal, polypropylene, polyphenylene oxide, polysulfone, polyacrylate, polyphenylene sulfide, liquid crystal polymer, phenolic resin, urea resin, melamine resin, melamine-phenolic resin, epoxy resin, diallyl phthalate are used. Resins, thermosetting resins such as unsaturated polyester resins, and insulating inorganic binders are used.

In this case as well, if the content and particle size of the magnetic material are the same as those of the layer 32 containing the magnetic material, a good heating source can be obtained.

The conductive layer 33 is made of a material having a volume resistivity of 1010 Ωcm or less, for example, a metal layer of aluminum, nickel, chromium, nichrome, copper, silver, gold, platinum, etc., tin oxide, etc. by vapor deposition, sputtering, etc. It can be provided as a metal oxide layer such as indium oxide or a conductive paint layer mixed with carbon or metal particles.

Although the conductive support 11 containing a magnetic material has been described above, the present invention is not limited to the above materials or configurations.

Next, the photosensitive layer 15 will be described. Examples of the inorganic photosensitive layer include amorphous Si, amorphous Se, 5e-Te compound, 5e-
Te-CR compound, 5e-As compound, CdS, Zn
Examples include O.

Next, the organic photosensitive layer 15 will be explained, but first, the laminated photosensitive layer will be described.

The charge generation layer 21 is a layer mainly made of a charge generation substance,
A binder resin may be used if necessary.

Binder resins include polyamide, polyurethane,
Polyester, epoxy resin, polyketone, polycarbonate, silicone resin, acrylic resin, polyvinyl butyral, polyvinyl formal, polyvinyl ketone,
Polystyrene, poly-N-vinylcarbazole, polyacrylamide, etc. are used.

Examples of the charge generating substance include CI Pigment Blue 25 [Color Index (CI) 21180],
CI Pigment Red 41 (CI 21200),
C.I. Acid Red 52 (CI 45100), C.I. Basic Red 3 (CI 45210), and a phthalocyanine pigment having a porphyrin skeleton,
Azo pigments having a carbazole skeleton (JP-A-53-95)
033), an azo pigment having a distyrylbenzene skeleton (described in JP-A-53-133455)
, an azo pigment having a triphenylamine skeleton (Japanese Unexamined Patent Publication No. 5
3-132547), an azo pigment having a dibenzothiophene skeleton (described in JP-A-54-21728), an azo pigment having an oxadiazole skeleton (described in JP-A-54-12742), Azo pigments having a fluorenone skeleton (described in JP-A No. 54-22834), azo pigments having a bisstilbene skeleton (described in JP-A-54-17733), azo pigments having a distyryloxadiazole skeleton ( Japanese Patent Publication No. 54-2129
Azo pigments having a distyrylcarbazole skeleton (described in JP-A-54-17734), CI Pigment Blue 16 (CI 7410)
0), C.I. Butt Brown 5 (CI73410), C.I. Butt Dye (CI
73030), and perylene pigments such as Argo Scarlet B (manufactured by Violet) and Indance Scarlet R (manufactured by Bayer).

Among these charge generating substances, azo pigments are preferred.

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

The binder resin is suitably used in an amount of 0 to 100 parts by weight, preferably 0 to 100 parts by weight, based on 100 parts by weight of the charge generating substance.
-50 parts by weight.

The charge generation layer is prepared by dispersing a charge generation substance together with a binder resin if necessary using a ball mill, attritor, sand mill, etc. using a solvent such as tetrahydrofuran, cyclohexane, dioxane, dichloroethane, etc., diluting the dispersion liquid appropriately and applying it. It can be formed by Application can be performed using a dip coating method, a spray coating method, a bead coating method, or the like.

The thickness of the charge generation layer is suitably about 0.01 to 5 .mu.m, preferably 0.1 to 2 .mu.m.

The charge transport layer 23 can be formed by dissolving or dispersing a charge transport substance and a binder resin in a suitable solvent, coating the solution on the charge generation layer, and drying the solution. Moreover, a plasticizer, a leveling agent, etc. can also be added if necessary.

Charge transport materials include hole transport materials and electron transport materials.

As hole transport substances, poly-N-vinylcarbazole and its derivatives, poly-γ-carbazolylethyl glutamate and its derivatives, pyrene-formaldehyde condensate and its derivatives, polyvinylpyrene, polyvinylphenanthrene, polyvinylpyrene, oxazole derivatives, Oxadiazole derivatives, imidazole derivatives,
Triphenylamine derivatives, 9-(p-diethylaminostyryl)anthracene, 1,1-bis-(4-dibenzylaminophenyl)propane, styrylanthracene, styrylpyrazoline, phenylhydrazones, α-
Examples include electron-donating substances such as phenylstilbene derivatives and benzidine derivatives.

Examples of electron transport substances include chloranil, bromoanil, tetracyanoethylene, tetracyanoquinone dimethane, 2,4.7-trinitro-9-fluorenone, 2,4,5.7-tetranitro-9-fluorenone, 2, 4,5.7-Titranitroxanthone, 2.4.
8-1-linitrothioxanthone, 2,6.8-1-linitro 4H-indeno(1,2-b)thiophene-4
-one, 1.3.7-trinitrodibenzothiophene-5,5-dioxide, and other electron-accepting substances.

These charge transport substances may be used alone or in a mixture of two or more.

Binder resins include polystyrene, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyester,
Polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, polyvinylidene chloride, polyacrylate resin, phenoxy resin, polycarbonate, cellulose acetate resin, ethyl cellulose resin, polyvinyl butyral, -15 = polyvinyl formal, polyvinyl toluene, poly -N
- Thermoplastic or thermosetting resins such as vinyl carbazole, acrylic resins, silicone resins, epoxy resins, melamine resins, urethane resins, phenolic resins, and alkyd resins.

As the solvent, tetrahydrofuran, dioxane, toluene, monochlorobenzene, dichloroethane, methylene chloride, etc. are used.

The appropriate thickness of the charge transport M23 is about 5 to 50 μs.

Next, a case where the photosensitive layer 15 has a single layer structure will be described.

In this case as well, most of the materials are of a functionally separated type consisting of a charge generating substance and a charge transporting substance.

That is, the compounds shown above can be used as the charge generating substance and the charge transporting substance.

A single-layer photosensitive layer can be formed by dissolving or dispersing a charge generating substance, a charge transporting substance and a binder resin in a suitable solvent, coating the solution and drying the solution. Moreover, a plasticizer, a leveling agent, etc. can also be added if necessary.

=16- As the binder resin, in addition to using the binder resin mentioned above for the charge transport layer 23 as is, the binder resin for the charge generation layer 2
The binder resins listed in 1 may be used in combination.

The single-layer photosensitive layer is formed by dipping coating, spray coating, bead coating, etc. using a coating solution in which a charge generating substance, a charge transporting substance, and a binder resin are dispersed using a dispersion machine using a solvent such as tetrahydrofuran, dioxane, dichloroethane, or cyclohexanone. Can be formed by coating.

The thickness of the monolayer photosensitive layer is suitably about 5 to 50 μm.

Note that in the present invention, it is also possible to further provide an insulating layer on the photosensitive layer 15.

Further, in the present invention, as shown in FIG. 3, an undercoat layer 13 is provided between the conductive support containing a magnetic material and the photosensitive layer.
By providing this, it is possible to further improve the first effect of the present invention, and it is also possible to improve adhesiveness.

The undercoat layer 13 may be made of an inorganic material such as Sin or AR203 provided by a method such as vapor deposition, sputtering, or anodization, or may be made of polyamide resin (Japanese Patent Laid-Open Nos. 58-30757 and 58-98739). ), alcohol-soluble nylon resin (JP-A-60-196766), water-soluble polyvinyl butyral resin (JP-A-60-2325)
No. 53), polyvinyl butyral resin (Japanese Unexamined Patent Publication No. 58
106549), a resin layer made of polyvinyl alcohol, etc. can be used.

Further, a resin subbing layer in which pigment particles such as ZnO1TiO7 and ZnS are dispersed can also be used as the subbing layer.

Further, as the subcoat M13 of the present invention, a silane coupling agent, a titanium coupling agent, a chromium coupling agent, etc. can also be used.

The thickness of the undercoat layer 13 is suitably 0 to 5 μm.

As the resin used for the protective layer 17, ABS resin, A
C3 resin, olefin vinyl copolymer resin, chlorinated polyether, allyl resin, phenol resin, polyacetal, polyamide, polyamideimide, polyarylate,
Polyaryl sulfone, polybutylene, polybutylene terephthalate, polycarbonate, polyether sulfone, polyethylene, polyethylene terephthalate, polyimide, methacrylic resin, polymethylpentene, polypropylene, polyphenylene oxide, polysulfone, polystyrene, AS resin, butadiene-styrene resin, polyurethane, poly Examples include vinyl chloride, polyvinylidene chloride, and epoxy resin.

In addition, from the viewpoint of wear resistance, polytetrafluoroethylene resin, fluorine resin, and silicone resin can be added as additives to lower the wear coefficient and improve wear resistance and scratch resistance. The wear resistance can also be improved by dispersing inorganic compounds such as chloride, tin chloride, and potassium titanate into the resin.

The thickness of this surface protective layer is 0.5 to 10 μm, preferably 1 to 5 μm.

In the present invention, the magnetic material that absorbs the energy of a high-frequency magnetic field and generates heat contained in the photosensitive layer has an imaginary part μr'' of complex relative magnetic permeability of 0.1 used in the conductive support.
It is preferable to use the above materials, and examples of such magnetic materials include magnetite, Ni-Zn ferrite, and NxF.
e, 04 ferrite, Mn-Mg ferrite, Mn
-Zn-based ferrite, NiCrZn ferrite, γ-hematite, magnetite, ferrox planer, and the like.

The electrophotographic photoreceptor of the present invention can be obtained by incorporating the above-mentioned magnetic materials into the photosensitive layer of the photoreceptor. At this time, any of the above layers may contain a magnetic substance,
When the amount of the magnetic material in the layer containing the magnetic material is 5 weight percent or more and 95 weight percent or less, preferably 10 weight percent or more and 90 weight percent or less, it is possible to heat the layer in the wild. Further, since magnetic substances often absorb visible light, there is a risk that the light will not hit the charge generating substance, so it is preferable not to include the magnetic substance in a layer above the charge generating layer.

In order to heat the electrophotographic photoreceptor of the present invention, it is preferable to form a high-frequency magnetic field so that the magnetic material in the photoreceptor is influenced by the electromagnetic field.

FIG. 6a is a cross-sectional view showing an example of a method of heating the electrophotographic photoreceptor of the present invention, in which a voltage is applied by a high-frequency generator 41 to an electrode body 42 below a conductive support 11 containing a magnetic material. This generates a high-frequency magnetic field, and the magnetic material absorbs the energy of this magnetic field and converts it into heat. As the high frequency generator 41, a magnetron or the like can be used. The electrode body 42 can be provided with seven electrodes 51 and 52 of an insulator 53, as shown in FIGS. It is not limited.

The electrode main body 42 that generates such a high-frequency magnetic field is made of a conductive support 11 containing a magnetic material, as shown in FIG. 6a.
Although it is preferable to place the electrodes 51 and 52 close to the conductive support 11, it is also possible to place the electrodes 51 and 52 in close contact with the conductive support 11.

FIG. 6 is a sectional view showing another example of a heating method, in which a high frequency voltage is applied between the electrode body 43 and the conductive portion 44 of the support. As the electrode body 43, one shown in FIG. 8 is used, and as described above, it is preferable to provide it close to or in close contact with the support 11 containing a magnetic substance.

One or more such electrode bodies 42 and 43 can be used.

When heating the electrophotographic photoreceptor of the present invention in an image forming apparatus, the heating temperature is relatively low (
(90℃ or less, preferably 70℃ or less), the photoconductor can be used when heating the photoconductor, but if the recovery treatment is performed at a temperature higher than that, the photoconductor cannot be used when heating the photoconductor. It is better to set it so that it is not possible.

Furthermore, when the photoreceptor is heated to a high temperature (70°C or higher, preferably 90°C or higher), the recovery effect occurs in a short time; however, when heated at such a high temperature, the toner may fuse onto the photoreceptor. Therefore, before using the photoreceptor, it is necessary to cool it to a predetermined temperature (a temperature that does not pose a problem for use). In thermal theory, settings should be made so that the photoreceptor cannot be used during this high-temperature heat treatment.

In addition, as an example of the use of the cooling means, if there is a risk that the temperature of the photoconductor may rise too much when the heating means is activated, the cooling means may be activated at the same time as the heating means to prevent overheating. It is also possible to use

As a cooling means, blowing cooling air
121482), a method using a refrigerant, etc., but the method is not limited thereto.

However, lowering the temperature of the photoreceptor below room temperature is not preferable because dew condensation occurs.

Furthermore, if the method of heating a photoreceptor according to the present invention is used, since the heating element is in contact with the photosensitive layer, the photosensitive layer can be heated efficiently.
There is also extremely little temperature unevenness. In addition, it also has the advantage that the temperature rises quickly at the start of heating.

〔Example〕

EXAMPLES Next, the present invention will be explained in more detail with reference to examples, but the present invention is not limited to the following examples.

Example 1 A coating liquid with the following composition was applied to the inner wall of an aluminum cylinder with an outer diameter of 40 mm and a length of 250 mm and dried to form a magnetic material/!
1 (approximately 8 μm).

[Magnetic layer coating liquid]

4-Methyl-2-pentanone 70! Next, on this aluminum cylinder No. 7, a charge generation layer coating liquid and a charge transport layer coating liquid having the following compositions were applied, dried, and a charge was generated! (0.1 μm), forming a charge transport M (20 voices).

[Charge generation layer coating liquid]

Trisazo pigment with the following structural formula 2 parts by weight cyclohexanone 150 #2-butanone
50" [Charge transport layer coating liquid] Charge transport material having the following structural formula: 100 parts by weight Polycarbonate 100 parts by weight (Panlite C-1400 manufactured by Teijin Kasei Corporation) Tetrahydrofuran
The organic photoreceptor prepared above 800 nm was printed using a laser printer (Ricoh PC Laser 6000).
), and the probe of the surface electrometer was set at a position where the surface potential of the photoreceptor could be measured immediately after charging.

A 2.45 GHz magnetron was used as a high frequency power source, and the photoreceptor temperatures were controlled at 25°C (room temperature), 40°C, 45°C, 50°C, 60°C, and 70°C using separately provided electrodes. . After setting each condition, the laser printer was repeatedly used to measure the surface potential immediately after charging. FIG. 9 shows the relationship between surface potential and photoreceptor temperature when 4000 sheets were printed.

Example 2 Ni-Zn ferrite (average particle size 1 μm, μr″-5
A subbing layer coating solution, a charge generation layer coating solution, and a charge transport layer coating solution having the following compositions were sequentially coated on a support made of a polyethylene terephthalate film in which 25% by weight of 2.45 GHz) was dispersed and aluminum was vapor-deposited. It was dried to form a subbing layer (3 μm), a charge generation N (0.3 μm), and a charge transport layer (21 μm).

[Subbing layer coating liquid]

Titanium dioxide 10 parts by weight Toluylene-2,4-diisocyanate 0.2 2-butanone 100 parts 4-methyl-2-pentanone 60 [Charge generation layer coating liquid] Metal-free phthalocyanine (X type) 2 parts by weight Cyclo Hexanone 80I + Tetrahydrofuran 100 IT [Charge transport layer coating liquid] Charge transport substance having the following structural formula 80 parts by weight Tetrahydrofuran 800 nNext, this electrophotographic photoreceptor was coated with a conductive layer and bonded with a belt, and then used for mounting. photoreceptor.

The organic photoreceptor created as described above is printed on a laser printer L.
P4080, and a surface electrometer probe was set so that the surface potential of the photoreceptor could be measured immediately after charging. Using the same high frequency power source as in Example 1, the photoreceptor was set to be heated at 52° C. for 10 minutes only when the printer was started, using a separately provided electrode.

The printer set as above (10℃, 15%),
Under the conditions of (25°C, 65%) and (30°C, 90%'), 3,000 copies were made in a cycle mode of start (8 minutes) -> continuous copying of 300 copies -> pause (10 minutes).

Comparative Example 1 Printing was carried out in the same manner as in Example 2 except that high-frequency magnetic field energy was not supplied to the magnetic material.

Table 1 shows the surface potentials and image characteristics of the 3000th sheet of the photoreceptors of Example 2 and Comparative Example 1.

Table-1 Q: No decrease in density or scumming is observed.

△=No density decrease is observed, but background staining becomes noticeable.

x: Density decreases significantly, and background stains also become noticeable.

Example 3 A coating solution with the following composition was applied to the inner wall of an aluminum cylinder with an outer diameter of 80 mm and a length of 340 mm and dried to form a magnetic layer (
Approximately 10 voices) were formed.

[Magnetic layer coating liquid]

Ferox Planar particles 7 parts by weight (average particle size 0, 7 pm, μr”=20 at 2.45GH
z) Modified silicone resin 10 parts by weight (
Manufactured by Shin-Etsu Silicone Co., Ltd., ESlooIN) Toluene
100 parts by weight 2-butanone
50 parts by weight Next, a charge transport layer coating liquid, a charge generation layer coating liquid, and a protective N coating liquid having the following compositions were sequentially coated and dried on this aluminum cylinder to form a charge transport layer (20, um) and a charge transport layer (20, um). A generation layer (0.3 μm) and a protective layer (4 μm) were provided.

[Charge transport layer coating liquid]

Charge transport material with the following structural formula: 80 parts by weight Polycarbonate 100 parts by weight (Panlite C-1400 manufactured by Teijin Kasei Corporation) Tetrahydrofuran
800 parts by weight [Charge generation layer coating liquid] Disazo pigment with the following structural formula 3 parts by weight Toluylene-2,4-diisocyanate 0.1 parts by weight Cyclohexanone 100 parts by weight Tetrahydrofuran 200 parts by weight [Protective layer coating liquid] Conductive titanium (Mitsubishi Metals) 100 parts by weight toluene
240 parts by weight butanol
The organic photoreceptor prepared in the amount of 60 parts by weight or more was mounted on a copying machine Ricopi-FT5510, and a reference image disclosed in JP-A-54-61938 was exposed to light as means for detecting the charge level of the photoreceptor. - A method was used in which the 4th charge was determined from the toner density after development. When the charge level of this copying machine drops to the equivalent of +680V, the photoreceptor is heated by a high frequency power source (same as in Example 1) and a separately provided electrode, and is operated for 10 minutes to maintain the temperature at 90''±5°C. Ta.

Immediately thereafter, air at room temperature was blown onto the surface of the photoreceptor using a separately provided fan, and when the photoreceptor was cooled to 50° C., it was set to resume copying (copying was disabled during heating and cooling). Also, for the experiment, a surface electrometer probe was set to detect the surface potential of the photoreceptor immediately after charging.
5000 copies were made in an environment of 20° C.-65%.

Comparative Example 2 Copying was carried out in the same manner as in Example 3, except that the heating means and cooling fan were not operated.

FIG. 10 shows the surface potentials measured in Example 3 and Comparative Example 2.

31-Example 4 Mn-Mg ferrite particles (average particle size 0, 3 pm, μr″=1st2.45GHz) in phenolic resin
) was dispersed at 32% by weight, and a cylinder with an outer diameter of 80 mm and a length of 340 mm was formed by extrusion molding,
A conductive layer of aluminum was provided thereon by vacuum evaporation.

A charge generation layer coating liquid and a charge transport layer coating liquid having the following compositions were applied thereon and dried to sequentially form a charge generation layer (0.2 μm) and a charge transport layer (18 μm).

[Charge generation layer coating liquid]

Disazo pigment with the following structural formula: 2 parts by weight Tetrahydrofuran 80 Ethyl Celsolve 120 [Charge transport layer coating liquid] Charge transport material with the following structural formula: 100 parts by weight - 32
= Tetrahydrofuran 800 nm The organic photoreceptor prepared above was transferred to a copying machine Ricopy-FT5.
510 modified for negative charging, and a surface electrometer probe was set so that the surface potential of the photoreceptor immediately after charging could be measured. In this copying machine, when the charge level of the photoreceptor drops to 1,700V or less, the photoreceptor is heated to 47°C using a high frequency power source (same as in Example 1) and a separately provided electrode.
It was set to heat for 5 minutes. Further, during this heating, 5000 copies were continuously made under the same environment as in Example 2.

Comparative Example 3 Copying was carried out in the same manner as in Example 4 except that high-frequency magnetic field energy was not supplied to the magnetic material.

Table 2 shows the surface potential of Example 4 and Comparative Example 3 and 5
The image characteristics of the 000th sheet are described below.

Table-2 0: No decrease in density or background staining observed.

Δ: No decrease in density is observed, but background staining becomes noticeable.

x: Density decreases significantly, and background stains also become noticeable.

Example 5 An intermediate layer coating solution, a charge generation layer coating solution, and a charge transport layer coating solution having the following compositions were sequentially coated and dried on the same support as that used in Example 2 to form an intermediate layer (0, 3 voices), charge generation N (0,
A charge transport layer (20 μm) was formed.

[Intermediate layer coating liquid]

water
150 parts methanol 2
00 parts [Charge generation layer coating liquid] Disazo pigment with the following structural formula Double Shabu cyclohexanone 160 parts by weight 2-butanone
40 parts by weight [Charge transport layer coating liquid] Charge transport material having the following structural formula 100 parts by weight Tetrahydrofuran 800 parts by weight Next, a conductive layer was applied to this electrophotographic photoreceptor and belt bonding was performed to prepare a photoreceptor for mounting. .

The organic photoreceptor prepared as described above is copied to the copier Ricopy-FT2.
050, and a surface electrometer probe was set so that the surface potential of the photoreceptor immediately after charging could be measured. Also,
The photoconductor temperature was set to always be 55℃ using a high frequency power supply and electrodes, and 400℃ was continuously applied in an environment of 20℃-65%.
0 copies were made.

Comparative Example 4 Copying was carried out in the same manner as in Example 5 except that high-frequency magnetic field energy was not supplied to the magnetic material.

FIG. 11 shows the surface potentials measured in Example 5 and Comparative Example 4.

Example 6 A coating solution having the following composition was applied onto an aluminum cylinder with an outer diameter of 40 mm and a length of 250 mm and dried to form a subbing layer (2,5 mm).
μm) was formed.

[Subbing layer coating liquid]

Toluylene-2,4-diisocyanate 1 double portion 4
-Methyl-2-pentanone 70 parts by weight Tetrahydrofuran 70 parts by weight Then,
On this subbing layer, a charge generation layer coating liquid and a charge transport layer coating liquid having the following compositions were applied and dried.
), a charge transport layer (20 μm) was formed.

[Charge generation layer coating liquid]

Trisazo pigment with the following structural formula: 2 parts by weight Cyclohexanone: 150 parts by weight 2-butanone: 50 parts by weight [Charge transport layer coating liquid] Charge transport material with the following structural formula: 100 parts by weight Tetrahydrofuran: 800 parts by weight or more The photoreceptor was mounted on a laser printer (Ricoh PC Racer 6000), and a probe of a surface electrometer was set at a position where the surface potential of the photoreceptor immediately after charging could be measured. A 2.45 GHz Macnetron was used as a high frequency power source, and an electrode was installed between the transfer and charging areas to set the photoreceptor temperature to always be 50''C. ) 3000 sheets were printed continuously under the following environment.

Comparative Example 5 Puddings 1 to 1 were carried out in the same manner as in Example 6 except that high-frequency magnetic field energy was not supplied to the magnetic material.

FIG. 12 shows the surface potentials measured in Example 6 and Comparative Example 5.

Example 7 An intermediate layer coating solution, a charge generation layer coating solution, and a charge transport layer coating solution having the following compositions were sequentially applied and dried on a polyethylene terephthalate film having an aluminum conductive layer to form an intermediate JW.
(3μm), charge generation layer (0.3μm), charge transport layer (
21 μs).

[Intermediate layer coating liquid]

Titanium dioxide 3 parts by weight Methanol 80 parts Isopropyl alcohol 100 parts by weight [Charge generation layer coating liquid] Ni-Zn ferrite (same as above) 3 parts by weight Charge generating substance with the following structural formula 2 parts by weight Cyclohexanone 160 parts by weight Tetrahydrofuran 40 parts by weight υ [Charge transport layer coating liquid] Charge transport material having the following structural formula 80 parts by weight Tetrahydrofuran 800 parts by weight Next, this electrophotographic photoreceptor was coated with a conductive layer and bonded with a belt to form a photoreceptor for mounting. As a body.

The organic photoreceptor created as described above is printed on a laser printer L.
P4080, and a surface electrometer probe was set so that the surface potential of the photoreceptor could be measured immediately after charging. Using the same high frequency power source as in Example 6, the photoreceptor was set to be heated at 48° C. for 12 minutes only when the printer was started, using a separately provided electrode.

The printer configured as above was installed as follows (10℃, 15℃)
%), (25℃, 65%) and (30℃, 90%) Start (10 minutes) → Continuous copying of 300 sheets → Pause (1
3000 copies were made in cycle mode (0 minutes).

Comparative Example 6 In Example 7, printing was carried out in the same manner as in Example 7 except that high-frequency magnetic field energy was not supplied to the magnetic material.

Table 3 shows the surface potential of Example 7 and Comparative Example 6 and 30
Describe the image characteristics of the 00th sheet.

Table-3 0: No decrease in concentration or background staining observed.

△: No decrease in density is observed, but background staining becomes noticeable.

x: The temperature decreases by 1 degree, and the background stain becomes noticeable.

Example 8 On an aluminum cylinder with an outer diameter of 80 mm and a length of 340 mm, a subbing layer coating liquid, a charge transport layer coating liquid, and a charge transport layer coating liquid having the following compositions were coated.
Apply the charge generation layer coating liquid and the protective layer coating liquid in sequence and dry.
A subbing layer (0.3 μm), a charge transport layer (20 μm), a charge generation layer (0.2 μm), and protection 1 (3 μm) were formed.

[Subbing layer coating liquid]

Water 150 parts by weight Methanol 200 parts by weight [Charge transport layer coating liquid] Charge transport substance having the following structural formula 70 parts by weight Tetrahydrofuran 850 parts by weight [Charge generation layer coating liquid] Disazo pigment having the following structural formula 3 parts by weight Toluylene-2 ,4-diisocyanate 0.1 parts Cyclohexanone 100 parts Trahydrofuran 200 parts by weight [Protective layer coating liquid] Conductive titanium (Mitsubishi Metals) 100 parts Part luene
240 parts by weight butanol
The organic photoreceptor prepared in the amount of 60 parts by weight or more was mounted on a copying machine Ricopi-FT5510, and a reference image disclosed in JP-A-54-61938 was exposed to light as means for detecting the charge level of the photoreceptor. - A method was used in which the 4th charge was determined from the toner density after development. When the charge level of this copying machine drops to the equivalent of +680V, the photoreceptor is heated using a high frequency power source (same as in Example 6) and a separate electrode, and the temperature is maintained at 80°±5°C for 10 minutes. I activated it. Immediately after this, room temperature air was blown onto the surface of the photoreceptor using a separate fan, and the surface was cooled down to 50°C.
It was set to restart copying (copying was disabled during heating/cooling). Further, for the experiment, a surface electrometer probe was set so that the surface potential of the photoreceptor immediately after charging could be detected, and 5,000 copies were made in an environment of 2° C.-65%.

Comparative Example 7 Copying was carried out in the same manner as in Example 8, except that the heating means and cooling fan were not operated.

FIG. 13 shows the surface potentials measured in Example 8 and Comparative Example 7.

44-Example 9 A cylinder having an outer diameter of 80 mm and a length of 340 mm was formed by extrusion molding of a phenol resin, and an aluminum conductive layer was provided thereon by a vapor deposition method. On this layer, a charge transport layer coating liquid, a charge generation layer coating liquid, and a protective layer coating liquid having the following compositions were sequentially applied and dried to form a charge transport layer (20 μO1), a charge generation layer (0.3 μO1), and a protective layer coating liquid. A layer (3 μs) was applied.

[Charge transport layer coating liquid]

Charge transport material having the following structural formula: 75 parts by weight Tetrahydrofuran 850 parts by weight [Charge generation layer coating liquid] NiFe2O4 particles (same as Example 6) 3 parts by weight Disazo pigment having the following structural formula: 2 parts by weight Cyclohexanone 200 parts by weight2 -Butane 100 parts by weight [Protective layer coating liquid] The organic photoreceptor prepared in the same manner as in Example 8 was transferred to the copier Ricobee F.
It was mounted on a T5510, and a surface electrometer probe was set so that the surface potential of the photoreceptor could be measured immediately after charging. This copying machine was set to heat the photoreceptor at 45° C. for 15 minutes using a high frequency power source (same as in Example 6) and separately provided electrodes when the charge level of the photoreceptor decreased to +700 V or less. Further, during this heating, 5,000 copies were continuously made under the same environment as in Example 7.

Comparative Example 8 Copying was carried out in the same manner as in Example 9 except that high frequency magnetic field energy was not supplied to the magnetic material.

Table 4 shows the surface potential of Example 9 and Comparative Example 8 and 5
The image characteristics of the 000th sheet are described.

Table-4 Δ: No decrease in density is observed, but background staining becomes noticeable.

x: Density decreases significantly and background stains also become noticeable.

Example 10 On the same support as used in Example 7, a subbing layer coating solution, a charge generation layer coating solution, and a charge transport layer coating solution having the following compositions were sequentially applied and dried to form a subbing layer ( 5), charge generation layer (0,2μ
m), charge transport! (20 μm) was formed.

[Subbing layer coating liquid]

-47 = Tin oxide 2 parts by weight Toluene 100 parts by weight 2-butanone 70 parts by weight [Charge generation layer coating liquid] Disazo pigment with the following structural formula 2 parts by weight Cyclohexanone 160 parts by weight 2-butanone
40 parts by weight [Charge transport layer coating liquid] Charge transport material having the following structural formula 100 parts by weight Tetrahydrofuran 800 parts by weight Next, a conductive layer was applied to this electrophotographic photoreceptor and belt bonding was performed to prepare a photoreceptor for mounting. .

The organic photoreceptor prepared as described above is copied to the copier Ricopy-FT2.
050, and a surface electrometer probe was set so that the surface potential of the photoreceptor immediately after charging could be measured. In addition, using a high frequency power supply and electrodes, the photoreceptor temperature was set to always be 55℃, and the temperature of the photoreceptor was continuously
000 copies were made.

Comparative Example 9 In Example 0, copying was carried out in the same manner as in Example 1o except that high-frequency magnetic field energy was not supplied to the magnetic material.

FIG. 14 shows the surface potentials measured in Example 10 and Comparative Example 9.

〔effect〕

Since the present invention has the above configuration, it has the following remarkable effects.

i) The photoreceptor can be heated uniformly and efficiently.

ii) It is possible to provide a heating method in which the temperature rises quickly during heating.

m) It is possible to prevent dew condensation on the photoreceptor and smearing of the image at low temperatures.

(2) It can reduce the relative humidity of the photoreceptor atmosphere under high temperature and humidity conditions, preventing image blurring and reduction in image density.

(2) Charging properties of organic photoreceptors can be improved.

[Brief explanation of the drawing]

1, 2a, 2b, 3 and 4 are schematic sectional views of the electrophotographic photoreceptor of the present invention, and FIGS. 5a and 5 are representative of the present invention. FIGS. 6a and 6b are drawings for explaining the method of heating an electrophotographic photoreceptor according to the present invention, and FIG.
, No. 7, and FIG. 8 are drawings showing the structure of the electrode body. FIG. 9 is a diagram showing the relationship between surface potential and photoreceptor temperature when 4,000 sheets were printed using the electrophotographic photoreceptor of the present invention, and FIGS. 10, 11, 12, 13, and FIG. 14 is a graph showing the relationship between the number of copies and surface potential when copies are made using the electrophotographic photoreceptors obtained in the present invention and comparative examples. DESCRIPTION OF SYMBOLS 11--Electroconductive support containing magnetic material, 13--Undercoat layer, 15-Photosensitive layer, 17--Protective layer, 21-Charge generation layer, z3--Charge transport layer, 31--Electroconductivity Base, 3
2 layer containing magnetic material, 33... conductive layer, 34...
Substrate containing magnetic material, 41...high frequency generator, 42
・Electrode body, 43 Electrode body, 44・Conductive part, 45-
Portion containing magnetic material, 51. Electrode, 52. Electrode, 5
3. Insulator, 54. Electrode.

Claims (1)

[Claims] (1) In an electrophotographic photoreceptor in which a photosensitive layer is provided on a conductive support, the conductive support and/or photosensitive layer absorbs the energy of a high-frequency magnetic field and contains a magnetic material that becomes a source of magnetic loss and generates heat. An electrophotographic photoreceptor comprising: