JPH04311783A - Dispersion liquid for forming coating film and method for forming coating film - Google Patents

Abstract

PURPOSE:To provide a method for forming a coating film having high uniformity and quality, especially a photo-sensitive film having high picture-quality and durability. CONSTITUTION:A dispersion liquid having excellent dispersibility of pigment is applied to a supporting member to form a coating film having high uniformity and quality. Especially, a photo-sensitive film having high picture-quality and durability is produced by applying a coating liquid having excellent dispersibility of a photoconductive pigment to the surface of a cylindrical supporting member using a circular slide-hopper coater, a circular extrusion coater or a circular small-amount dip coater in high precision and efficiency.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a coating film-forming dispersion in which organic and inorganic pigments are uniformly dispersed and a coating film-forming method thereof, and particularly relates to a coating film-forming dispersion containing a photoconductive pigment dispersed therein. Regarding the forming method.

0002

BACKGROUND OF THE INVENTION The present invention applies when coating a dispersion of a coloring agent on building materials, arts and crafts, etc., when forming a magnetic recording material by coating a dispersion of a magnetic powder onto a film or disk, etc. Particularly applicable to various dispersions, such as when forming an electrophotographic photoreceptor by coating a dispersion of organic/inorganic pigments, especially photoconductive pigments, on a conductive substrate or conductive cylindrical support. In any of the above cases, the quality of the pigment dispersion in the dispersion liquid is an important factor that determines the quality of the product obtained by coating.

[0003] Conventionally, measurement of sedimentation degree, turbidity, particle size distribution, etc. of a dispersion liquid, or measurement of characteristics of coated products,
The quality of the dispersion liquid is determined by performing electron micrograph evaluation.

0004

[Problems to be Solved by the Invention] However, these methods all test the quality of the dispersion liquid or finished product, and the conditions for preparing the dispersion liquid, that is, under what conditions the dispersion liquid should be prepared? It does not provide knowledge of the
It remains a mere follow-up record and does not actively contribute to technological development. In order to improve technical or production efficiency, it is considered necessary to reexamine the conditions for obtaining a good dispersion from the beginning.

[0005]

OBJECTS OF THE INVENTION The object of the present invention is to provide a method for preparing a dispersion in which inorganic or organic pigments are uniformly dispersed and coating the dispersion on a support to form a high-quality coating film. It is about providing.

Another object of the present invention is to provide a method for forming a high-quality coating film for an electrophotographic photoreceptor by coating an organic or inorganic pigment, particularly a photoconductive organic or inorganic pigment, on a cylindrical support. be.

[0007]

[Structure of the Invention] As a result of studies conducted in accordance with the above-mentioned objectives, it has been found that the fluidity characteristics of the dispersion are closely related to the requirements for a dispersion having excellent coating film properties and, by extension, good target properties. Based on this knowledge, the structure of the present invention is as follows: A dispersion liquid containing dispersed pigments is applied onto a support so that the dispersion liquid used for coating film formation has fluidity characteristics satisfying the following formulas (1) and (2). This is achieved by a coating film-forming dispersion characterized by having the following characteristics.

[0008]τ=τ0+ηDn...(1)1
．． 0≧n≧0.7...In formula (2), τ is the shear stress of the dispersion (dyne/cm2), D is the shear rate (1/sec), and η is the viscosity coefficient (dyne/cm2・s).
ec), τ0 is the value of τ when D=0.

Further, a dispersion containing a pigment dispersed in a binder resin solution and having flow characteristics defined by the above formulas (1) and (2) is transferred to a cylindrical support using a circular slide hopper, a circular extrusion, or a circular small amount. This is achieved by a coating film forming method using a dip coating machine.

Furthermore, by using a photoconductive pigment as the pigment, a coating film-forming dispersion for electrophotography and a cylindrical photoreceptor can be obtained.

The method for forming a coating film of the present invention includes, for example, forming a coating film using a colored dispersion liquid for building materials, forming a coating film using a magnetic dispersion liquid for magnetic recording materials, and forming a coating film using a magnetic dispersion liquid for electrophotographic materials. This includes the formation of a coating film using a dispersion of a pigment, and the formation of a coating film using a dispersion of a photoconductive pigment is particularly important.

By the way, the quality characteristics of the various coating films as products depend on the dispersion state of the dispersion liquid, and in the present invention, the good dispersion state of the dispersion liquid is determined by the flow characteristics of the dispersion liquid according to the above formula (1) and the flow characteristics of the dispersion liquid. It appears by controlling within the specific range regulated in (2).

[0013] The flow characteristics of the dispersion liquid are measured, for example, using a commercially available RotoVisco RV100 type flow characteristics meter.

As shown in FIG. 1, this measuring instrument consists of an outer cylinder that is rotationally driven by a motor M, and an inner cylinder that is immersed in the dispersion liquid in the outer cylinder and supported by a support frame via a spring. It consists of The outer cylinder is sheared by the motor M at a shearing rate D(
1/sec), a torque based on the viscosity coefficient η (dyne/cm2·sec) of the intervening dispersion liquid is generated in the inner cylinder, and this torque causes twisting of the spring. The torsion angle of this spring is detected by a torque sensor, and the shear stress τ (dyne/cm2) of the dispersion liquid is measured.

FIG. 2 is a schematic graph for explaining the flow characteristics of the dispersion liquid expressed by the formula (1): τ=τ0+ηDn (1). The graph shows the relationship between dispersion speed D (1/sec) (horizontal axis) and shear stress τ (dyne/cm2) (vertical axis) for each of dispersions A, B, C, and D having different dispersion characteristics. The flow characteristics are shown, and the index n of each flow characteristic calculated by the microcomputer from the graph is 1.0, 0.7, 0.5, and 1.
2 is shown. The vertical axis also shows the Pascal (Pa) scale as the shear stress τ.

In FIG. 2, for example, in dispersion A, the index n is 1.0, and as the shear rate D increases, the shear stress τ increases linearly, and the viscosity coefficient η increases as the shear rate increases. It is a so-called Newtonian liquid that remains constant regardless of change,
It is called an ideal liquid. Such a dispersion does not change in viscosity during the coating process, has stable physical properties, and can provide an extremely homogeneous coating film.

In the present invention, in addition to dispersions exhibiting the properties of Newtonian liquids, dispersions that are accompanied by an increase in viscosity due to intermolecular association in the process of increasing the shear rate D, molecular orientation, molecular decomposition, and aggregation are used. This includes dispersions with a decrease in viscosity due to dissociation of
) have poor coating processability and are excluded in the present invention.

[0018] Furthermore, the dispersion liquid B, which is said to be accompanied by a decrease in viscosity, has an index n of 0.7, and although it is accompanied by a decrease in viscosity in the process of increasing the shear rate D, there is no problem in performing coating processing. range, and is the lower limit of the present invention. However, in the case of the dispersion C, the index n is 0.5, and the dispersion B
If the index n is less than 0.7, the physical properties such as viscosity change significantly during the coating process, causing coating unevenness, coating streaks, dripping, etc., and are therefore unsuitable and outside the scope of the present invention.

That is, in the present invention, the quality of the dispersion liquid is determined by the shear rate D (1/sec) and the shear stress τ (dyne/cm2).
is defined by an index n of the flow characteristics of the dispersion liquid measured by a rotobisco flow characteristics measuring device or the like, with the parameter n, and the scope of the present invention is limited by the index n.

Furthermore, as mentioned above, the quality of the dispersion according to the present invention is determined by the index n, but at the same time, the quality of the dispersion has a great deal to do with the viscosity of the dispersion. Therefore, in the present invention, the viscosity coefficient η is considered together with the index n, and this viscosity coefficient η is expressed as: viscosity coefficient η (dyne/cm2・sec) = shear stress τ
There is a relationship of (dyne/cm2)/shear rate D (1/sec), and when the shear stress corresponding to the shear rate D is measured by the rotoviscometer, the viscosity coefficient η is calculated at the same time.

[0021] In addition, the units displayed on the measuring instrument are Pascal (Pa) for shear stress and centipoise (CP) for viscosity coefficient η, so in the present invention, η
The value of is expressed as (CP) for convenience.

[0022] Here, the conversion formula for the units is as follows.

Shear stress 1 Pa = 10 dyne/cm 2 Viscosity coefficient 1 dyne/cm 2 ·sec = 100 CP Note that for the viscosity coefficient η (CP) shown in the examples below, the conventional viscosity coefficient η is used due to functional constraints of the measuring instrument.

For example, a specific shear rate of 300 (1/sec
) is indicated by the slope of the straight line connecting the origin and the intersection point B or C of the vertical axis of the shear stress τ and the characteristic curve of the dispersion liquid B or the dispersion liquid C.

In addition, in the measurement of the flow characteristics, the shear rate D=0
(1/sec) to, for example, D=300(1/sec
There is a measurement of going to c) and a measurement of a return to D=0 (1/sec), but in the measurement of the return, τ0 often shows a finite value. However, in the present invention, since the forward measurement is used as a reference, it is processed approximately as τ0=0.

The above are the flow characteristics of the dispersion containing the pigment according to the present invention.

Next, the composition of the dispersion according to the present invention will be described.

Examples of inorganic pigments contained in the coating film according to the present invention include zinc oxide, titanium oxide, aluminum oxide, cadmium sulfide, mercury sulfide, lead sulfide, tin oxide, magnetite, ferrite, carbon black, and metal powder. Inorganic pigments such as Rose Bengal (C.I. No. 4543
5), Pigment Red (C.I.No.60745)
There are organic pigments such as aniline blue (C.I. No. 50405), phthalocyanine blue (C.I. No. 74160), and pigment yellow (C.I. No. 21095). Examples of photoconductive inorganic pigments include photoconductive zinc oxide, titanium oxide, cadmium sulfide, selenium, arsenic selenide, tellurium selenide, crystal silicon, amorphous silicon, and gallium arsenide. There are pigments.

Among the organic and inorganic pigments, pigments selected depending on the intended use include, for example, polyamide resins, polystyrene resins, polyvinyl butyral resins, acrylic resins, methacrylic resins, vinyl chloride resins, vinyl acetate resins, epoxy resins, and polyurethane resins. resin, phenolic resin, polyester resin, alkyd resin, polycarbonate resin,
Resins such as silicone resin, melamine resin, vinyl chloride-vinyl acetate copolymer resin, vinyl chloride-vinyl acetate-maleic anhydride copolymer resin, cellulose resin, polyvinyl alcohol resin, casein, etc., such as butylamine, diethylamine, ethylenediamine, isopropanol Amine, monoethanolamine, triethanolamine, triethylenediamine, N,N-dimethylformamide,
Acetone, methyl ethyl ketone, cyclohexanone, benzene, toluene, xylene, chloroform, 1,2-
A dispersion is formed by mixing and dispersing it in a solution obtained by dissolving it in an organic solvent such as dichloroethane, dichloromethane, tetrahydrofuran, dioxane, methanol, ethanol, isopropanol, ethyl acetate, butyl acetate, or dimethyl sulfoxide. To create the dispersion, solvent 1
A dispersion liquid is prepared by dissolving 1 to 300 parts by weight of a binder resin in 1,000 parts by weight and mixing and dispersing 10 to 1,000 parts by weight of a pigment per 100 parts by weight of the binder resin in the resulting solution. In preparing the dispersion, the type and amount of the binder resin and the type and amount of the solvent are selected so as to satisfy the fluidity characteristics. The obtained dispersion liquid is applied onto a support such as a film, plate, or cylinder by spray coating, blade coating, etc.
Known coating means such as roll coating and dip coating, and especially in the case of a cylindrical support, circular coating means that surround the outer periphery of the support such as circular slide hopper coating, circular extrusion coating, circular small amount dip coating, etc., which will be described later. A coating film is formed by coating.

Next, in the method for forming a coating film of the present invention, a method for manufacturing an electrophotographic photoreceptor drum, which is particularly important, and a method for manufacturing an organic photoconductive photoreceptor drum, which has recently been emphasized. It will be explained in further detail.

As the electrophotographic material, an inorganic photoreceptor having a photosensitive layer mainly composed of an inorganic photoconductive substance such as selenium, zinc oxide, cadmium sulfide, etc. or an organic photosensitive material mainly composed of an organic photoconductive substance described below can be used. Among them, the organic photoreceptor has a wide selection range of photoconductive substances, can obtain a photoreceptor with arbitrary characteristics depending on the purpose, and can be manufactured at low cost by coating processing. It has become important because of its advantages. The organic photoreceptor is preferably of a functionally separated type, and typically has a single-layer structure comprising an intermediate layer, a photosensitive layer containing a charge-generating substance and a charge-transporting material on a conductive support, as shown in FIG. a charge transport layer comprising;
It has a laminated structure including a charge generation layer containing a charge generation substance and, if necessary, a protective layer. FIG. 3(a) shows a photoreceptor having a single-layered photosensitive layer 4 containing an intermediate layer 5 and a charge-generating substance and a charge-transporting substance on a conductive support 1, and FIG. 3(b)
This is an example of a photoreceptor having a photosensitive layer in which an intermediate layer 5, a charge transport layer 2, and a charge generation layer 3 are laminated in this order on a conductive support 1. Further, FIG. 3(c) shows an intermediate layer 5 on the conductive support 1,
A photoreceptor having a photoreceptor layer in which a charge generation layer 3 and a charge transport layer 2 are laminated in this order, FIG. 3(d) is an example of a structure in which a protective layer 6 is provided on the surface of the photoreceptor shown in FIG. 3(b). be.

[0032] The organic photosensitive layer including the plurality of layers is usually formed by coating on a cylindrical support constituting a conductive support in order to be incorporated into an image forming apparatus. In the present invention, when a plurality of layers are formed on the cylindrical support, at least one of the layers is coated with a circular coater surrounding the support, such as a circular slide hopper coater, a circular extrusion coater or a circular extrusion coater. Applied by a circular small volume dip coater.

In this case, the coating liquid is replenished in the required amount,
There is no waste in the coating liquid, and high processing accuracy allows for highly efficient coating, such as continuous coating. Furthermore, when the circular coating machine is used, even when the fluidity characteristics of the dispersion are such that the exponent n in the above formula representing the characteristics approaches 0.7, highly accurate coating processing is possible, and the dispersion has excellent electrophotographic properties. As a result, high durability during image formation is ensured, and a photoreceptor free from image defects such as image unevenness, streaks, and spots can be obtained.

The photosensitive layer of the photoreceptor is preferably of a functionally separated type containing a charge-generating substance and a charge-transporting substance made of a photoconductive pigment, and examples of the charge-transporting substance include oxazole derivatives, oxadiazole derivatives, and thiazole derivatives. , thiadiazole derivatives, triazole derivatives, imidazole derivatives, imidazolone derivatives, imidazolidine derivatives, bisimidazoline derivatives, styryl compounds,
Hydrazone compounds, pyrazoline derivatives, oxazolone derivatives, benzothiazole derivatives, benzimidazole derivatives, quinazoline derivatives, benzofuran derivatives, acridine derivatives, phenazine derivatives, aminostilbene derivatives, poly-N-vinylcarbazole, poly-1-vinylpyrene, poly-9- Examples include vinylanthracene.

Among the charge transport materials, particularly preferred are carbazole derivatives represented by the following general formula (1), hydrazone compounds represented by general formulas (2) to (5), and general formula (6).
There are pyrazoline derivatives of formula (7), styryl compounds of general formula (7), and amine derivatives of general formula (8).

[0036]

[Chemical formula 1]

In the general formula (1), R1 is a substituted or unsubstituted aryl group, R2 is a hydrogen atom, a halogen atom,
Substituted or unsubstituted alkyl group, alkoxy group, amino group, hydroxyl group, substituted amino group, R3 represents a substituted or unsubstituted aryl group, substituted or unsubstituted heterocyclic group.

[0038]

[Case 2]

In the general formula (2), R4 and R5 each represent a hydrogen atom or a halogen atom, R6 and R7 each represent a substituted or unsubstituted aryl group, and Ar1 represents a substituted or unsubstituted arylene group.

In the general formula (3), R8 is a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, and R9 is a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. group, Q is a hydrogen atom,
halogen atom, alkyl group, substituted amino group, alkoxy group or cyano group; p represents an integer of 0 or 1;

In the general formula (4), R10 is a substituted or unsubstituted aryl or a substituted or unsubstituted heterocyclic group, R11 is a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, X is a hydrogen atom,
A halogen atom, an alkyl group, a substituted amino group, an alkoxy group or a cyano group, and q represents an integer of 0 or 1.

In the general formula (5), R12 and R13 represent a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, or a substituted or unsubstituted aryl group.

Examples of the alkyl group include methyl group, ethyl group, propyl group, butyl group, etc.; examples of the aralkyl group include benzyl group, phenethyl group; and examples of the aryl group include phenyl group, α-naphthyl group, Examples include β-naphthyl group. As a substituent, a halogen atom,
Examples include an alkyl group, an alkoxy group, a substituted amino group (dimethylamino group, diethylamino group, dipropylamino group, dibenzylamino group), and the like. Further, D represents a substituted or unsubstituted phenyl group or a substituted or unsubstituted carbazolyl group. Specifically, the above-mentioned groups are mentioned, and R
14, R15, and R21 represent the same as R12 and R13. R16, R17, R18, R19, R20, and R22 represent an alkyl group, an alkoxy group, a halogen atom, or the like.

[0044]

[Chemical formula 3]

In the general formula (6), l is an integer of 0 or 1, R23, R24, and R25 are substituted or unsubstituted aryl groups, R26 and R27 are hydrogen atoms, and have 1 to 4 carbon atoms.
or a substituted or unsubstituted aryl group or aralkyl group (however, R26 and R27 are not both hydrogen atoms, and when l is 0, R26 is not a hydrogen atom).

In the general formula (7), R28 and R29 represent a substituted or unsubstituted alkyl group or phenyl group, and an alkyl group, an alkoxy group, or a phenyl group is used as the substituent. R30 represents a substituted or unsubstituted phenyl group, naphthyl group, anthryl group, fluorenyl group, or heterocyclic group, and as a substituent, an alkyl group, an alkoxy group, a halogen atom, a hydroxyl group, or a phenyl group is used. R31 represents a hydrogen atom, a substituted or unsubstituted alkyl group, or a phenyl group. R32, R33, R34, R35 are hydrogen atoms,
Represents a halogen atom, an alkyl group, an alkoxy group, or an alkylamino group.

In the general formula (8), Ar2 and Ar3 represent a substituted or unsubstituted phenyl group, and a halogen atom, an alkyl group, a nitro group, or an alkoxy group is used as a substituent. Ar4 represents a substituted or unsubstituted phenyl group, naphthyl group, anthryl group, fluorenyl group, or heterocyclic group, and substituents include an alkyl group, an alkoxy group, a halogen atom, a hydroxyl group, an aryloxy group, an aryl group, an amino group, Nitro groups, piperidino groups, morpholino groups, naphthyl groups, anthryl groups and substituted amino groups are used. However, as a substituent for a substituted amino group, an acyl group, an alkyl group,
An aryl group or an aralkyl group is used.

Specific examples of compounds included in the general formulas (1) to (8) are listed in JP-A-60-172044, page 6, bottom right column, line 2 to page 21, top right column, line 20. It is described in.

Charge generating substances contained in the photosensitive layer or charge generating layer of the photoreceptor include: (1) Monoazo pigments, polyazo pigments, metal complex azo pigments, pyrazolone azo pigments, stilbene azo pigments, and thiazole azo pigments. Azo pigments such as pigments (2) Perylene pigments such as perylene anhydride and perylene imide (3) anthraquinone derivatives, anthanthrone derivatives, dibenzpyrenequinone derivatives, pyrantrone derivatives,
Anthraquinone or polycyclic quinone pigments such as violanthrone derivatives and isoviolanthrone derivatives (4) Indigoid pigments such as indigo derivatives and thioindigo derivatives (5) Phthalocyanine pigments such as metal phthalocyanines and metal-free phthalocyanines (6) Diphenylmethane pigments Pigments, carbonium pigments such as triphenylmethane pigments, xanthene pigments and acridine pigments (7) quinone imine pigments such as azine pigments, oxazine pigments and thiazine pigments (8) methine pigments such as cyanine pigments and azomethine pigments (9) quinoline Pigments (10) Nitro pigments (11) Nitroso pigments (12) Benzoquinone and naphthoquinone pigments (13)
Naphthalimide pigments (14) Perinone pigments such as bisbenzimidazole derivatives are included. Among the various pigments mentioned above, particularly preferred charge generating substances include polycyclic quinone pigments represented by the following general formulas (9) to (11).

[0050]

[C4]

In each of the above general formulas, X represents a halogen atom, a nitro group, a cyano group, an acyl group or a carboxyl group,
n represents an integer of 0 to 4, and m represents an integer of 0 to 6.

[0052] Furthermore, bisazo compounds represented by the following general formulas (12) to (14) can be used as charge generating substances.

[0053]

[C5]

In this general formula (12), Ar5 and Ar6 are each a substituted or unsubstituted carbocyclic aromatic ring group, or a substituted or unsubstituted heterocyclic aromatic ring group, R36,
R37 is an electron-withdrawing group or a hydrogen atom (however, R3
6, at least one of R37 is -CN, a halogen such as -Cl, an electron-withdrawing group such as -NO2), and X of A is -
OH group, -N(R39)-R40 or -NHSO2R4
1 (However, R39 and R40 are each a hydrogen atom, a substituted or unsubstituted alkyl group, R41 is a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group), Y is a hydrogen atom, a halogen atom, a substituted or an unsubstituted alkyl group, an alkoxy group, a carboxyl group, a sulfo group, a substituted or unsubstituted carbamoyl group, or a substituted or unsubstituted sulfamoyl group (however, when m is 2 or more, different groups may be used) ), Z is an atomic group necessary to constitute a substituted or unsubstituted carbocyclic aromatic ring group or a substituted or unsubstituted heterocyclic aromatic ring group, R38 is a hydrogen atom, substituted or unsubstituted B is a substituted or unsubstituted aryl group, n is an integer of 1 or 2, and m is an integer of 0 to 4.

Among the general formulas (12) above, a particularly preferable charge generating substance is shown in the following general formula (12a).

[0056]

[C6]

However, Ar7, Ar8 and A have the general formula (12
) is the same as defined in ). More preferred are Ar7 and Ar8 in general formula (12a).
represents a substituted or unsubstituted phenyl group, and substituents include alkyl groups such as methyl group and ethyl group, alkoxy groups such as methoxy group and ethoxy group, halogen atoms such as chlorine atom and bromine atom, hydroxyl group and cyano group. A compound selected from

Further, a preferable charge generating substance in the charge generating layer according to the present invention is represented by the following general formula (13).

[0059]

[C7]

In the above A, Z is an atomic group necessary to constitute a substituted or unsubstituted aromatic carbocycle or a substituted or unsubstituted aromatic heterocycle, and Y is a hydrogen atom, a hydroxyl group, a carboxyl group, or an ester thereof. group, a sulfo group, a substituted or unsubstituted carbamoyl group, or a substituted or unsubstituted sulfamoyl group, R42 is a hydrogen atom,
Substituted or unsubstituted alkyl group, substituted or unsubstituted amino group, substituted or unsubstituted carbamoyl group, carboxyl group or its ester group, or cyano group,
Ar9 represents a substituted or unsubstituted aryl group, R43 represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, or a substituted or unsubstituted aryl group.

Of the general formula (13), the following general formula (1)
Particularly preferred are bisazo compounds having a carbazole group in 3a).

[0062]

[Chemical formula 8]

In the general formula (13a), R44, R45
is an alkyl group, an alkoxy group or an aryl group, R46,
R47, R48, R49, R50, R51 are hydrogen atoms,
halogen atom, alkyl group, alkoxy group, amino group,
They are hydroxyl group and aryl group.

Further, a preferable charge generating substance in the charge generating layer according to the present invention is represented by the following general formula (14).

[0065]

[Chemical formula 9]

In the general formula (14), X1 and X2 are
respectively, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a nitro group,
It represents a cyano group, a hydroxy group, or a substituted or unsubstituted amino group, and at least one of X1 and X2 is a halogen atom.

p and q each represent an integer of 0, 1 or 2, p and q are never 0 at the same time, and p
When q is 2, X1 may be the same or different groups, and when q is 2, X2 may be the same or different groups.

Furthermore, Ar10 of A represents an aromatic carbocyclic group or an aromatic heterocyclic group having at least a fluorinated hydrocarbon group. Z represents a group of nonmetallic atoms necessary to form a substituted or unsubstituted aromatic carbocycle or a substituted or unsubstituted aromatic heterocycle.

m and n each represent an integer of 0, 1 or 2. However, m and n never become 0 at the same time.

The halogen atoms represented by X1 and X2 in general formula (14) include chlorine atom, bromine atom, fluorine atom, and iodine atom. At least one of X1 and X2 has a halogen atom.

The alkyl group represented by X1 and X2 is preferably a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms. Examples of such alkyl groups include methyl group, ethyl group, β -cyanoethyl group, i
Examples include so-propyl group, trifluoromethyl group, t-butyl group, and the like.

The alkoxy group represented by X1 and X2 is preferably a substituted or unsubstituted alkoxy group having 1 to 4 carbon atoms, and examples of such alkoxy groups include methoxy group, ethoxy group, Examples include β-chloroethoxy group and sec-butoxy group.

Furthermore, substituted or unsubstituted amino groups represented by X1 and X2 include, for example, alkyl groups,
those substituted with an aryl group (preferably a phenyl group), such as an N-methylamino group, an N-ethylamino group,
N,N-dimethylamino group, N,N-diethylamino group, N-phenylamino group, N,N-diphenylamino group, and further acetylamino group substituted with acyl group, p
-chlorobenzoylamino group and the like. In the general formula (14), p and q each represent 0, 1 or 2, but p and q are never 0 at the same time, preferably p = 1, q = 0 or p = 1, q This is the case when =1.

Furthermore, when p or q is 2, X1 or X2 can be the same or different groups, respectively.

The bisazo compound represented by the general formula (14) is preferably represented by the following general formulas (14a) and (14b).
, (14c), (14d).

[0076]

[Chemical formula 10]

[0077]

[Chemical formula 11]

In the above formula, X1a, X1b, X2a and X
2b represents a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a nitro group, a cyano group, a hydroxy group, or a substituted or unsubstituted amino group, and X1a, X1b, X2a
and X2b, at least one is a halogen atom. X1a and X1b, and X2a and X2b are
The groups may be the same or different from each other.

Ar'' in the general formula (14)
It is synonymous with 10.

Y has the same meaning as the substituent for Z in the general formula (14).

The bisazo compound represented by the general formula (14) can be easily synthesized by a known method.

[0082] Furthermore, the above general formulas (9) to (14)
Specific compound examples include, for example, JP-A-60-172044.
No. 23, bottom right column, line 1 to page 46, top right column, line 8.

Among the phthalocyanine pigments, pigments preferably used in the present invention include, for example, metal phthalocyanines containing copper, cobalt, lead, zinc, etc. as central atoms, and metal-free phthalocyanines that do not contain these. Preferably, α-type, β-type, γ-type, X-type, τ-type, τ'-type, η-type, η'-type, etc. are used. Further detailed descriptions of such phthalocyanine pigments are given in JP-A-62-79470 and JP-A-62-47054.

A particularly preferred phthalocyanine pigment is a black angle of 2 in the CuKα characteristic X-ray diffraction spectrum.
θ is at least 9.6±0.2° and 27.2±0.2°
A photoreceptor, for example, the third
When producing a photoreceptor having the layer structure shown in Figure (C), first, aluminum, steel, stainless steel, copper, brass, A conductive layer is formed by depositing or laminating a conductive material such as a metal on a metal cylinder such as zinc or a plastic cylinder to form a conductive layer.0.
An intermediate layer 5 with a thickness of 01-2 μm is provided.

The intermediate layer 5 is made of the binder resin for the coating film described above, preferably polyamide resin, polyvinyl butyral resin, vinyl chloride-vinyl acetate copolymer resin, vinyl chloride-vinyl acetate-maleic anhydride copolymer resin, cellulose. A solution prepared by dissolving resin, polyvinyl alcohol resin, casein, etc. in a solvent such as acetone, methyl ethyl ketone, dichloroethane, methanol, ethanol, isopropanol, water, etc. is applied onto the cylindrical support using known coating methods such as spray coating and dip coating. Alternatively, it is applied by the circular application means.

The intermediate layer 5 is provided for the purpose of shielding surface defects of the support 1, adhesion to the photosensitive layer, blocking charge injection from the support 1, adjusting image quality of the photosensitive layer, etc., and has a film thickness of 0.0.
If the thickness is less than 1 μm, the above objective will not be achieved, and if it is more than 2 μm, the residual charge on the photosensitive layer during image exposure will increase, fog will increase, and the electrophotographic performance will deteriorate in the process of repeated image formation. become.

Next, a charge generation layer 3 containing a charge generation substance made of the photoconductive pigment is provided on the intermediate layer 5. To form the charge generation layer 3, for example, polyester, methacrylic resin, acrylic resin, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyvinyl acetate, melamine resin, polyurethane, styrene-acrylic copolymer, styrene-butadiene copolymer, etc. Polymer, vinylidene chloride-acrylonitrile copolymer, vinyl chloride-
Vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer, silicone resin, styrene-alkyd resin, polyvinyl carbazole, polyvinyl butyral, and others JP-A-60-172044, JP-A-60-1
No. 72045, No. 63-65444, No. 63-148
No. 263, JP-A No. 1-269942, JP-A No. 1-2699
1 to 100 parts by weight of the polycarbonate resin described in No. 42 and the like is mixed and dissolved in 1000 parts by weight of a solvent selected for the charge generation layer from the group of solvents described for the intermediate layer. The charge generating substance was added to the resulting solution as a binder resin (100%).
10 to 1000 parts by weight, preferably 20 to 5 parts by weight
00 parts by weight are mixed and dispersed, and the resulting dispersion is applied onto the intermediate layer 5 using a circular coating means such as a circular slide hopper coater, a circular extrusion coater, or a circular small-volume dip coater, until the film thickness after drying is 0. It is applied to a thickness of .05 to 3 μm.

When the thickness of the charge generation layer is less than 0.05 μm, it is difficult to obtain a uniform coating layer, and sufficient charge generation cannot be obtained by imagewise exposure, resulting in insufficient sensitivity. Also 3μm
If this value is exceeded, the area where the image exposure light does not reach increases, and the charges generated on the surface are trapped and the residual charges become large, causing fatigue deterioration when image formation is repeated. If the content of the charge generating substance in the binder resin is less than 10 parts by weight, sensitivity will be insufficient and residual charge will increase, and if it exceeds 1000 parts by weight, the accepted potential will decrease and charging will be poor.

The dispersion liquid for forming the charge generation layer 3 by coating must have a dispersion state in which n falls within the range of 0.7 to 1.0 in FIG. 2, which shows the flow characteristics of the dispersion liquid. is an essential requirement, and therefore suitable binder resins and solvents are selected. A slide hopper coating machine, a circular extrusion coating machine, and a circular small quantity dip coating machine for forming the charge generation layer 3 are shown in FIGS. 4, 5, and 6.

A charge transport layer 2 is provided on the charge generation layer 3. That is, a binder resin and a solvent for the charge transport layer are selected from the resin group and solvent group described for the charge generation layer and the intermediate layer, and 50 to 300 parts by weight of the binder resin is dissolved in 1000 parts by weight of the solvent. 30 parts by weight or more, preferably 30 to 300 parts by weight, of the charge transport substance per 100 parts by weight of the binder resin are mixed and dissolved in the solution to prepare a charge transport layer coating solution, and this is applied onto the charge generation layer as described above. The layer is coated to a thickness of 5 to 50 μm, preferably 10 to 40 μm using any of the coating methods described at the time of layer formation.
A thick charge transport layer 2 is formed.

If the layer thickness of the charge transport layer 2 is less than 5 μm, the potential will drop and the charge transport function will be insufficient, resulting in a decrease in sensitivity. If it exceeds 50 μm, the charge transport path will become too large and the sensitivity will decrease. causing a shortage.

Next, when the amount of the charge transporting substance relative to the binder resin is less than 30 parts by weight, the charge transporting function is insufficient, resulting in insufficient sensitivity, and when it exceeds 300 parts by weight, the dark resistance of the photosensitive layer decreases. Causes potential shortage.

The photoreceptor described above has the layer structure shown in FIG. 3(c), with the charge generation layer 3 as the lower layer and the charge transport layer 2 as the lower layer.
3(b) and 3(d), in which the charge transport layer 2 is the lower layer and the charge generation layer 3 is the upper layer, or as shown in FIG. 3(a). The photoreceptor may have a single-layer photosensitive layer in which a charge-generating substance and a charge-transporting substance are mixed.

Photosensitive layer 4 containing dispersed photoconductive pigments:
Also, a coating machine for forming the charge generation layer 3 will be explained.

In FIG. 4, 10 is a cylindrical support conveyed in direction A, 11 is a circular slide hopper coating machine, 12 is a coating liquid distribution chamber of the coating machine 11, 13 is a coating liquid distribution slit, 14 is a coating liquid supply pipe, 15 is a liquid receiver,
16 is a hopper edge, 17 is a coating liquid slide surface, and 18 is a coating layer. FIG. 5(a) is a sectional view of the coating machine 11 including the cylindrical support 10, and FIG. 4(b) is a partially broken view thereof. FIG.

During coating, the required amount of the coating liquid S is supplied to the coating liquid supply pipe 14 by a pump or the like, and the coating liquid S is supplied to the coating liquid distribution chamber 12.
distributed uniformly in the circumferential direction by the distribution slit 1
3, and flows uniformly down the slide surface 17 in the circumferential direction. Thereafter, a bead of the coating liquid S is formed between the hopper edge 16 and the outer peripheral surface of the cylindrical support 10, and the support 10 is conveyed in the direction of arrow A with this bead in contact with the outer peripheral surface of the support 10. A coating layer 18 is formed on the surface. According to such a coating machine, since the solvent evaporates quickly from the coating layer 18, a dry coating film can be easily obtained by providing a simple drying device. Further, since only the necessary amount of the coating liquid S is sent, there is no waste of the coating liquid, and the cost of materials can be reduced. In addition, since it is a circular coating method, seamless uniform coating is possible, and the coating film is determined by the liquid supply amount, viscosity, and moving speed of the object to be coated, making it easy to control the coating thickness. Since there is little variation in coating thickness, high quality and high productivity coating is possible. In the circular slide hopper coating machine,
The gap between the diameter of the end of the slide surface and the outer diameter of the cylindrical support is preferably 0.05 to 1 mm, more preferably 0.1 to 0.6 mm. The inclination angle of the sliding surface is 10° with respect to the horizontal
~70° is preferred, and 20° ~ 45° is more preferred.

The viscosity of the coating liquid is preferably within the range of 0.5 to 700 CP, more preferably 1 to 500 CP.

[0098] In order for the coating liquid to flow uniformly in the circumferential direction from the coating liquid distribution slit, in the slide hopper device, it is necessary to The slit resistance (Ps) is P
s/Pc≧80, more preferably 100 to 100,0
The range is 00.

Next, FIG. 5 is a sectional view of the circular extrusion coating machine 11', and the same parts as in FIG. 4 are given the same reference numerals. In the circular extrusion coating device 11', the amount of coating liquid S necessary for coating is supplied to the coating liquid supply pipe 14 by a pump or the like.
The coating liquid is distributed uniformly in the circumferential direction by the coating liquid distribution chamber 12, pushed out through the distribution slit 13, uniformly and continuously flows out from the hopper edge 16, and the coating liquid is distributed between it and the outer peripheral surface of the support. A bead is formed by which the coating layer 18 is applied.

[0100] The length of the hopper edge 16 is 0.1 to 10 m.
m, preferably 0.5 to 4 mm. The angle of inclination of the hopper edge is preferably within the range of 30° from the vertically downward direction, and more preferably within the range of 20° from the vertically downward direction. If the angle of inclination of the hopper edge exceeds 30°, the crosslinking of the coating solution will be shortened, making it difficult to obtain a good coating film.

[0101] Furthermore, in the extrusion coating machine 11',
By maintaining the relationship between the distribution chamber resistance (Pc) and the slit resistance (Ps) when the coating liquid flows through the coating liquid distribution slit in the range of Ps/Pc≧40, more preferably within the range of 40 to 100,000, It is possible to apply the liquid stably and uniformly.

These distribution chamber resistance (Pc) and slit resistance (Ps) may be determined depending on the coating liquid supply rate, viscosity, and supply pressure. Furthermore, in the extrusion coating machine 11', the hopper edge is 0.05 to 1 mm larger than the outer diameter of the object to be coated.
mm, more preferably a coating film thickness in the range of 2ho mm to 4ho mm, and a length in the coating direction of 0.1 to 10 mm, more preferably 0.5 to 4 mm.
Preferably, it has a diameter of 4 mm.

FIG. 6 is a sectional view of the circular small quantity dip coating machine 11'', in which the bottom plate 21 is fixed to the loading plate 20,
The liquid stopping blade 23 is connected to the upper surface of the bottom plate 21 and the pressing plate 2.
2 and are held tightly together. The coating liquid S is stored in a liquid tank 24, and a liquid replenishment plate 25 for replenishing the coating liquid S to the liquid tank 24 is provided on the upper surface of the liquid tank 24.
A pair of liquid supply ports 26 are provided in the .

[0104] The entire coating machine 11'' is formed in a cylindrical shape. The liquid stopping blade 23 is made of flexible rubber, synthetic resin, etc., and is configured to hold the support 10 in a narrow manner. .

Holes 27a, 27a', 27a'' are provided through the bottom plate 21, press plate 22, and liquid tank 24, and holes 27a, 27a', and 27a'' are provided in the liquid replenishment plate 25, each having a smaller diameter than the holes 27a, 27a', and 27a''. A hole 27b is provided through the blade 23, and a hole 27c having a smaller diameter than the hole 27b is provided through the blade 23.

Further, the periphery of the hole 27c of the blade 23 is in close contact with the outer peripheral surface of the support 10, and the periphery of the hole 27b of the liquid replenishing plate 25 faces the outer periphery of the support with an extremely small gap. Therefore, evaporation of the coating liquid during coating is suppressed, and rapid drying immediately after coating is prevented. In the liquid tank 24, a liquid storage chamber 28 is provided in its lower half, and a liquid reservoir 29 is provided in its upper half. A plurality of communication holes 30 are arranged in the circumferential direction to replenish the coating liquid S in the liquid reservoir 29 to the liquid storage chamber 28 in the lower half, and a reflux hole for overflow is provided in the outer peripheral wall of the storage section 28. 31, which is designed to keep the liquid level constant at all times. Further, a plurality of air holes 33 are provided in the inner circumferential wall of the accommodating portion 28 in the circumferential direction, and are communicated with the outside air via the holes 27b. In this circular small amount dip coating machine, a small amount of liquid at a constant level is stably held in the storage portion 28, and the circular liquid end surface contacts the outer periphery of the support to apply the liquid. Typical examples of the circular slide hopper coater 11, the circular extrusion coater 11', and the circular small-volume dip coater 11''' used in the photoreceptor manufacturing method of the present invention have been described above. is suitable for applying a coating liquid to a cylindrical support, and especially when forming the surface layer of a photoreceptor, there is little dissolution or erosion of the underlying layer, and uniform coating is possible at high speed. high quality,
High productivity can be achieved.

[0107] For coating the cylindrical support, for example, a conveying coating device 45 as shown in FIG. 7 is used. In the figure,
40a, 40b, 40c are cylindrical supports 10a, 10b
It is a spacer that alternately fits and connects (10c) etc.,
Continuous coating is made possible by a circular coater 41 that is conveyed in the vertical direction integrally with the support and performs the circular slide hopper coating, circular extrusion coating, or small circular dip coating. The support body is transported by gripping the spacers 40b and 40c fitted on the top and bottom of the support body 10b.
A pair of upper and lower gripping parts 42a and 42b that transport 0b upward
and a gripping tool 43B having a pair of upper and lower gripping parts 42c and 42d that grip spacers 40a and 40b fitted on the upper and lower sides of the support 10a and transport the support 10a upward. . The gripping tools 43A and 43B are supported by a device main body 45, and are moved through lifting members 46A and 46B screwed to ball screws 44A and 44B which are rotationally driven by a drive source (not shown) and coil springs 47A and 47B which are buffer members. They are connected to each other and are moved up and down as the elevating members 46A and 46B move up and down in conjunction with the rotation of the ball screws 44A and 44B. The lifting members 46A and 46B are moved up and down based on a predetermined program signal, so that while one lifting member is gripping the spacer and transporting the support upward, the other lifting member is gripping the spacer without colliding with each other. It is lowered with the support released, and the spacer below is grasped in order to convey the next support.

Reference numeral 49 denotes a support supplying hand, and if cylindrical supports are successively set on this by a robot or the like in accordance with the timing, the lifting movement of the hand to a predetermined position and the above-mentioned gripping tool are performed. In cooperation with the upward transport movement 43A or 43B, the support is continuously fed to a circular coater 41, coated, and dried by an air jet dryer 47 directly above the coater 41. A drum-shaped photoreceptor is formed. This photoreceptor is suction-carried and carried out of the apparatus by the carry-out hand 48.

In addition to the conveying and coating device 45, the cylindrical support is continuously conveyed vertically upward by a pair of left and right chain belts provided with a large number of elastic grippers, for example, as described in JP-A-56-101149. It may also be applied by

[0110]

[Examples] The present invention will be specifically explained below with reference to Examples, but the embodiments of the present invention are not limited thereto. Note that the following charge generation materials, charge transport materials, charge generation layers, and charge transport layers are CGM, CTM, CGL, and C
It is abbreviated as TL.

(Preparation of cylindrical support) Length 355.5 m
Prepare 11 aluminum tubes with an outer diameter of 80 mm and fill each tube with vinyl chloride-vinyl acetate-maleic anhydride copolymer (Sekisui Chemical Co., Ltd., S-LEC MF-10).
) Dissolve 10 parts by weight in 1000 parts by weight of methyl ethyl ketone, apply the resulting solution by a normal dip coating method,
This was dried to form an intermediate layer with a dry film thickness of 0.1 μm, and 11 cylindrical supports for testing were prepared.

(Preparation of photoreceptor for testing of the present invention) [Test No. 1~No. 3. Preparation of photoreceptor] (Formation of CGL (1)) A composition for CGL (1) having the following formulation was applied to three of the 11 supports having the intermediate layer using a sand grinder.
The dispersion was carried out for 4 hours to obtain a dispersion, which was coated and dried using a coating device 45 incorporating a circular slide hopper coating machine 11 shown in FIG. 4 to obtain test No. A 1 μm thick CGL (1) for one photoreceptor was formed.

Composition for CGL (1): 10 parts by weight of polyvinyl butyral resin (manufactured by Sekisui Chemical Co., Ltd.; S-LEC BX-1) CGM of the following structure (
1)
30 parts by weight
Methyl ethyl ketone
1
000 parts by weight Here, the viscosity coefficient η(CP) of the dispersion liquid
was 3.2, and the index n was 0.88.

[0114]

[Chemical formula 12]

(Formation of CGL (2)) Next, CGL (2)
The test No. 1 μm thick test No. 1 in the same manner as CGL (1) of photoreceptor
．． A CGL (2) for two photoreceptors was formed.

Composition for CGL (2); 10 parts by weight of polyvinyl butyral resin (manufactured by Sekisui Chemical Co., Ltd., S-LEC BM-S) CGM having the above structure
(1)
30 parts by weight
cyclohexanone

1000 parts by weight (formation of CGL (3)) then CGL (
1) in the same manner as CGL (1) except that the composition for 3) was used, the viscosity coefficient η (CP) was 5.2, and the index n = 0.75.
μm thickness test No. A CGL (3) for three photoreceptors was formed.

Composition for CGL (3): Polycarbonate resin (PCZ- manufactured by Mitsubishi Gas Chemical Co., Ltd.)
200) 10 parts by weight Vinyl chloride resin (Sekisui Chemical Co., Ltd., S-LEC MF-10)
1 part by weight CG of the above structure
M(1)
30 parts by weight cyclohexanone

1000 parts by weight (Formation of CTL (1)) Next, the following composition for CTL (1) was applied by ordinary dip coating on the three types of supports on which the CGL (1), CGL (2), and CGL (3) were formed. CTLs with a thickness of 18 μm were formed by coating and drying according to the test No. 1 method. 1.No. 2.No.
Three photoreceptors of No. 3 were obtained.

Composition for CTL (1): Polycarbonate resin (PCZ-200)
15
0 parts by weight CTM (1) with the following structure

150 parts by weight dichloromethane

1000 parts by weight

0
119]

[Chemical formula 13]

[Test No. 4~No. 6 Preparation of photoreceptor] (Formation of CTL (2)) The remaining 8 having the intermediate layer
A solution of the composition for CTL (2) having the following formulation is applied to three of the book supports by a coating device 45 in which a circular slide hopper coating machine 11 shown in FIG. 4 is incorporated in the coating section 41 of the device.・Dry and test No. 4~No. A CTL (2) with a thickness of 18 μm for 6 photoreceptors was formed.

Composition for CTL (2): Polycarbonate resin (PCZ-200)
15
0 parts by weight CTM (2) with the following structure

150 parts by weight dichloromethane

1000 parts by weight

0
122]

[Chemical formula 14]

(Formation of CGL (4)) Next, the above CTL (
Take one of the three supports on which 2) has been formed, and apply the composition for CGL (4) with the following formulation in a sandcliner.
The dispersion obtained by dispersing for 4 hours was coated and dried using the circular slide hopper coating device 45 to form a 1 μm thick CGL (4
) and test No. Four photoreceptors were obtained.

Composition for CGL (4): Polycarbonate (PCZ-200)

10 parts by weight Vinyl chloride resin (manufactured by Sekisui Chemical Co., Ltd., S-LEC EC-110) 1 part by weight CGM of the above structure (2)

50 parts by weight dichloroethane

1000 parts by weight The viscosity coefficient η (CP) of the dispersion is 6.8 and the index n is 0.80.
Met.

[0125]

[Chemical formula 15]

(Formation of CGL (5)) Next, the above CTL (
The other one of the three supports on which 2) was formed was taken, and the CTM content was changed to 80 parts by weight, and the rest was CTL (4).
Using the same composition for CGL (5), the viscosity coefficient η (CP
) was 7.4 and the index n was 0.72.
) and test No. 5 photoreceptors were obtained.

(Formation of CGL (6)) Next, the above CTL (
2) Take the remaining supports of the three supports formed,
Using the composition for CTL (6) with the following formulation, the viscosity coefficient η(
CGL with a thickness of 1 μm was prepared in the same manner as CGL (4) except that a dispersion liquid with CP) of 6.4 and index n of 0.88 was used.
(6) and test No. A photoreceptor of No. 6 was obtained.

[Test No. Preparation of Photoreceptor with Single Layer Structure in No. 7] (Preparation of Photosensitive Layer (1)) Next, one of the remaining five supports having the intermediate layer was taken, and the photosensitive layer (1) having the following formulation was taken. A dispersion obtained by dispersing the composition for 24 hours with a sand grinder is coated and dried using the coating device 45, which has the circular small amount dip coating machine 11'' incorporated in the coating section 41 of the device, to form a 20 μm thick photosensitive layer ( 1) Form and test no.
．． 7 photoreceptors were obtained.

Composition for photosensitive layer (1): Polycarbonate (PCZ-200)

150 parts by weight Vinyl chloride resin (manufactured by Sekisui Chemical Co., Ltd., S-LEC MF-10) 5 parts by weight CTM (1)

100 parts by weight CGM (1)

10
0 parts by weight cyclohexanone

1000 parts by weight The dispersion obtained by dispersing the above composition had a viscosity coefficient η (CP) of 23.5 and an index n of 0.76.

[Test No. 8. Preparation of comparative photoreceptor] (
Formation of CGL (7)) Next, the remaining 4 layers having the intermediate layer are formed.
Take one of the book supports and apply CGL (7) with the following formulation.
A dispersion obtained by dispersing the composition for 24 hours using a sand grinder was coated and dried using the coating device 45 incorporating the circular extrusion coater 11' to form a CGL (7) with a thickness of 1 μm.

Composition for CGL (7): Polyvinyl butyral resin (manufactured by Sekisui Chemical Co., Ltd., S-LEC BH-3) 50 parts by weight CGM (1)

80
Parts by weight Methyl ethyl ketone

1000 parts by weight The viscosity coefficient η(
CP) was 8.8, and the index n was 0.60.

(Formation of CTL (3)) The CGL (7)
A CTL (3) composition similar to that for CTL (1) was applied onto the support on which CTL (1) was formed using a coating device 45 incorporating a circular extrusion coater 11' and dried to form a CTL (18 μm thick). 3) and test No. A comparative photoreceptor of No. 8 was obtained.

[Test No. 9. Preparation of comparative photoreceptor] (
Formation of CTL (4)) Next, the remaining 3 with the intermediate layer
Take one of the book supports and apply the same composition for CTL (4) as in the case of CTL (1) to the circular extrusion coater 1.
1' is coated and dried by the coating device 45 incorporating
A μm thick CTL (4) was formed.

(Formation of CGL (8)) The above CTL (4)
A dispersion obtained by dispersing a composition for CGL (8) having the following formulation for 24 hours using a sand grinder was applied onto the support on which CGL (8) was formed using a coating device 45 incorporating a circular extrusion coating machine 11' and dried. A 1 μm thick CGL (8) was formed using test No. A comparative photoreceptor of No. 9 was obtained.

Composition for CGL (8): Polycarbonate resin (PCZ-200)
5
0 parts by weight CGM (1)

60 parts by weight cyclohexanone
1000 parts by weight The viscosity coefficient η (CP) of the dispersion is 11.2,
The index n was 0.63.

[Test No. Preparation of Comparative Photoreceptor with Single-layer Structure in No. 10] (Preparation of Photosensitive Layer (2)) Next, one of the remaining two supports having the intermediate layer was taken, and the photosensitive layer (2) having the following formulation was taken. ) was dispersed for 24 hours using a sand grinder, and a dispersion obtained was coated and dried using a coating device 45 equipped with a small circular dip coating machine 11'' to form a photosensitive layer (2) with a thickness of 20 μm. A comparative photoreceptor of .10 was obtained.

Composition for photosensitive layer (2): Polyester resin (manufactured by Toyobo Co., Ltd., Vylon 200)
200 parts by weight C
TM(1)

150 parts by weight CGM (1)

100 parts by weight dichloroethane

1000 parts by weight The viscosity coefficient η (CP) of the dispersion obtained by dispersing the above composition is 42.3, and the index n is 0.5.
It was 8.

[Test No. Preparation of 11 comparative photoreceptors]
(Formation of CGL (9)) Next, take the last remaining support having the intermediate layer, and disperse the CGL (9) composition having the following formulation for 24 hours using a sand grinder. A CGL (9) having a thickness of 1 μm was formed by coating and drying using a coating device 45 incorporating a slide hopper coater 11.

Composition for CGL (9): Polycarbonate resin (PCZ-200)
3
0 parts by weight Vinyl chloride resin (manufactured by Sekisui Chemical Co., Ltd., S-LEC MF-10) 10 parts by weight
CGM (1)

100 parts by weight dichloromethane

1000 parts by weight The viscosity coefficient η (CP) of the dispersion is 9.2, and the index n is 0.
．． It was 64.

(Formation of CTL (5)) The CGL (9)
A CTL (5) having a thickness of 18 μm is formed by dip coating the same composition for CTL (5) as in the case of CTL (1) using a normal dip coating device on the support on which CTL (1) is formed.
Test no. Eleven comparative photoreceptors were obtained.

[0141] The specifications of the samples are summarized in Table 1. The symbols used in the table have the following meanings.

[0142] In addition, CGL compositions are commonly dispersed for 24 hours using a sand grinder, and CTL compositions are commonly prepared using a mixed solution of 150 parts by weight of each CTM and 150 parts by weight of polycarbonate and 100 parts by weight of dichloromethane. be.

Binder used Polyvinyl butyral VB Polycarbonate PC Polyester
Es vinyl chloride
VC solvent cyclohexanone CHN dichloroethane DCE dichloromethane
DCM methyl ethyl ketone M
EK coating dipping method P1 Circular slide hopper method P2 Circular extrusion method P3 Circular small amount dipping method P4 Layer structure CTL top CGL bottom ACG
L top CTL bottom B single layer
C

[0144]

[Table 1]

(Test method) The above-mentioned photoreceptor for testing of the present invention No. 1~No. 7 and photoreceptor No. 7 for comparison test. 8
~No. Test No. 11 was attached to Konica U-Bix3035, and CGL was the lower layer and CTL was the upper layer.
Photoreceptors 1, 2, 3, 8, and 11 were negatively charged, and test No. 1 was used with CTL as the lower layer and CGL as the upper layer. 4,5,6,9
and test No. of single layer structure. Photoreceptors Nos. 7 and 10 were tested for electrostatic properties and image formation as positively charged. In addition, the test conditions are relative humidity 60% and temperature 20℃.
The actual test was repeated 10,000 times for each test under the atmosphere of It was shown to.

In addition, the black paper potential (VB) and white paper potential (VW) of the photoreceptor were measured before and after the 10,000th repeated photographing test, and the results are shown in Table 2.

[0147] The black paper potential (VB) in Table 2 is the surface potential of the photoreceptor for an original with a reflection density of 1.3, and the white paper potential (
VW) is the surface potential of the photoreceptor with respect to an original with a reflection density of "0", and was measured by placing an electrometer probe at the developing device before and after actual copying. In evaluating the image quality of the live-action test, we focused on the image density and the degree of fog, and the image density was 1.
．． “○” for 1 or more, “△” for 0.9 to 1.09, 0.9
Less than 0.10 is marked as "x", fog of 0.10 or more is marked as "x", and 0.10 or more is marked as "x".
02 to 0.09 was rated "△", and less than 0.02 was rated "○".

[0148]

[Table 2]

From Tables 1 and 2, the photoreceptor obtained by the manufacturing method of the present invention has better coating processing than the comparative photoreceptor, so it does not cause image defects such as streaks, unevenness, and spots. However, it has excellent electrophotographic performance, has high durability with little wear of the photosensitive layer during repeated image formation processes, and has other advantages such as excellent coating processing efficiency.

[0150]

Effects of the Invention As is clear from the above description, the method for manufacturing a photoreceptor of the present invention has excellent coating processability and productivity, and the resulting photoreceptor has
Effects such as no image unevenness, streaks, spots, etc. are produced, and the electrophotographic performance and durability during repeated use are excellent.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an apparatus for measuring flow characteristics of a dispersion liquid.

FIG. 2 is a graph showing the flow characteristics of a dispersion liquid.

3A, 3B, 3C, and 3D are cross-sectional views showing the layer structure of a photoreceptor; FIG.

FIG. 4(a) is a sectional view of a circular slide hopper coating machine, and FIG. 4(b) is a partially cutaway perspective view.

FIG. 5 is a cross-sectional view of a circular extrusion coater, and FIG. 6 is a cross-sectional view of a circular small-volume dip coater.

FIG. 6 is a front view of a coating device that transports and coats a cylindrical support.

[Explanation of symbols]

1... Conductive support 2... Charge transport layer 3... Charge generation layer 10... Cylindrical coated body (cylindrical support) 11,
11', 11'', 41...Coating machine 12...Coating liquid distribution chamber 13...Distributing slit 16...Hopper edge 23...Liquid stopping blade 24...Liquid tank 28...Liquid storage portions 40a, b, c...Spacer 41...Coating machine 42a , b, c, d...Gripping part 45...Coating device

Claims (8)

[Claims] [Claim 1] The dispersion liquid containing a dispersed pigment is applied on a support to form a coating film, and the dispersion liquid is characterized in that the dispersion liquid has fluidity characteristics satisfying the following formulas (1) and (2). Dispersion liquid for coating film formation. τ=τ0+ηDn…(1) 1.0≧n≧0
．． 7...(2) [where τ is the shear stress of the dispersion (dyne/cm2), D is the shear rate (1/s
c), η is the viscosity coefficient (dyne/cm2・sec), τ
0 is the value of τ when D=0. ] 2. The coating film-forming dispersion according to claim 1, wherein the pigment is a photoconductive pigment. [Claim 3] A dispersion containing a pigment dispersed in a binder resin solution and having flow characteristics defined by the following formulas (1) and (2) is applied to a cylindrical support using a circular slide hopper coating machine. How to form a coating film. τ=τ0+ηDn…(1) 1.0≧n≧0
．． 7...(2) [where τ is the shear stress of the dispersion (dyne/cm2), D is the shear rate (1/s
c), η is the viscosity coefficient (dyne/cm2・sec), τ
0 is the value of τ when D=0. ] 4. The coating film forming method according to claim 3, wherein the pigment is a photoconductive pigment. 5. A dispersion containing a pigment dispersed in a binder resin solution and having flow characteristics defined by the following formulas (1) and (2) is coated on a cylindrical support using a circular extrusion coater. A coating film formation method. τ=τ0+ηDn…(1) 1.0≧n≧0
．． 7...(2) [where τ is the shear stress of the dispersion (dyne/cm2), D is the shear rate (1/s
c), η is the viscosity coefficient (dyne/cm2・sec), τ
0 is the value of τ when D=0. ] 6. The coating film forming method according to claim 5, wherein the pigment is a photoconductive pigment. [Claim 7] A dispersion containing a pigment dispersed in a binder resin solution and having fluidity characteristics defined by the following formulas (1) and (2) is coated on a cylindrical support using a circular small-volume dip coater. A coating film formation method. τ=τ0+ηDn…(1) 1.0≧n≧0
．． 7...(2) [where τ is the shear stress of the dispersion (dyne/cm2), D is the shear rate (1/s
c), η is the viscosity coefficient (dyne/cm2・sec), τ
0 is the value of τ when D=0. ] 8. The coating film forming method according to claim 7, wherein the pigment is a photoconductive pigment.