JPH05323630A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain an electrophotographic sensitive body having high sensitivity and high durability as well as excellent mechanical strength. CONSTITUTION:Polycarbonate resin having allyl groups represented by the formula is incorporated into the electric charge transferring layer of an electrophotographic sensitive body and a hardened film of the electric charge transferring layer is formed by allowing the polycarbonate resin to react with the carbon-carbon double bond of an electric charge transferring material in the layer under heat or light energy. In the formula, each of R1 and R2 is H, 1-10C alkyl or aryl, R1 and R2 may bond to each other to form a ring and (n) is the degree of polymn.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photoreceptor having high sensitivity and high durability.

[0002]

2. Description of the Related Art In recent years, organic photoconductors (OPCs) have been used in copying machines,
Mostly used in printers. These OPCs have a structure in which a charge generation layer (CGL) and a charge transfer layer (CTL) are sequentially stacked. In CTL, a low molecular weight transfer material (CTM) is dissolved in a binder resin at a certain concentration to form a film. The addition of CTM lowers the mechanical strength inherent in the binder resin, and the CTL film becomes brittle and has a low tensile strength. This decrease in mechanical strength causes abrasion, scratches, peeling, cracks, etc. of the photoconductor. On the other hand, polyvinyl carbazole, polyvinyl anthracene, polyvinyl pyrene (M. Tolka et al. (J. Polym. Sci.
OL21.969) Proposed polymer) Japan Ha
rd Copy 89 'P. Attempts have been made to increase the molecular weight of CTL such as the vinyl polymer of hydrazone described in 67, but the CTL film is still fragile and the mechanical strength has not been improved. Further, the polymer CTM is not sufficient in terms of sensitivity, residual potential, etc. and has low durability as a photoreceptor. Further, it is proposed that CTM is dispersed in a binder resin and then the binder resin is cured.
Since the TM concentration is as high as 30 to 50%, the curing reaction is not sufficient, CTM comes out from between the resins and is worn, and the problem cannot be solved.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the circumstances of the prior art described above, and an object thereof is to provide an electrophotographic photoreceptor having excellent mechanical strength, high sensitivity and high durability. And

[0004]

According to the present invention, in an electrophotographic photoreceptor in which a charge generation layer and a charge transfer layer are sequentially laminated on a conductive support, the charge transfer layer has a polycarbonate represented by the following chemical formula 1. Provided is an electrophotographic photoreceptor, which comprises a charge transfer material containing a resin and reacting with a charge transfer material having a carbon-carbon double bond by heat or light energy.

[Chemical 1] (In the formula, R ₁ and R ₂ are hydrogen, an alkyl group having 1 to 10 carbon atoms, an aryl group, R ₁ and R ₂ together form a ring,
n represents the degree of polymerization. )

That is, the present inventors have made the CTL binder resin contain a polycarbonate resin having an allyl group,
Radicals or ions are generated by the energy of light or heat to react with a charge transfer material having a carbon-carbon double bond to increase the molecular weight and obtain a cured film of a high hardness charge transfer layer. I found out. The present invention has been made based on such findings.

Specific examples of repeating units of the polycarbonate resin having an allyl group represented by the above chemical formula 1 used in the present invention include those shown in Table 1 below.

[Table 1]

The binder resin of the present invention is shown in Table 1 above.
In addition to the homopolymer having the repeating unit shown in, copolymers with bisphenol monomers, dibasic acids such as terephthalic acid, isophthalic acid, adipic acid, and organopolysiloxane may be used. The copolymerization is Tg point of resin, film strength. , Friction coefficient, hardness, compatibility with CTM, etc. can be controlled. Examples of the copolymerizable monomer include the monomers shown in Table 2 below.

[Table 2]

The polycarbonate resin of the present invention has the above chemical formula 1.
The raw material allyl group-substituted bisphenol of the polycarbonate represented by, or the bisphenol and the copolymerization component are reacted with phosgene in the presence of an alkali or synthesized from dephenol with diphenyl carbonate. Polymerization was carried out using phosgene, an allyl group-substituted bisphenol homopolymer, an allyl group-substituted bisphenol copolymer, an allyl group-substituted bisphenol copolymer and an allyl-unsubstituted bisphenol copolymer, etc., and 0.7 g was dissolved in 100 ml of methylene chloride. The specific viscosity of the solution at 20 ° C. was 0.159 to 1.89.
P-tert as a terminal terminator in the range of 0
-Butylphenol, phenol, p-cumylphenol, p-tert-octylphenol and the like.

A charge transfer material (CTM) having a carbon-carbon double bond, which forms a cured film by reacting with a binder resin composed of the polycarbonate having an allyl group of the present invention.
Preferred are those having a triphenylamine structure represented by the following chemical formulas 2 to 4, and styrene derivatives represented by the chemical formula 5.

[0010]

[Chemical 2]

[0011]

[Chemical 3]

[0012]

[Chemical 4]

[0013]

[Chemical 5] (However, in reduction 2 of 4, R _3: hydrogen, methyl _{R 8, R 9, R 10} , R 11: hydrogen, identical or different,
Substituted or unsubstituted linear or branched alkyl group, or alkoxy group, substituted or unsubstituted aryl group, aryloxy group, aralkyl group, halogen, substituted or unsubstituted amino group R ₁₂ , R ₁₃ : same or phase Different, substituted or unsubstituted linear or branched alkyl group, or substituted or unsubstituted aryl group, substituted or unsubstituted amino group, or R ₁₂ and R ₁₃ bonded together to form a ring Z:- _{O -, - OCnH 2 n -} , - OCnH 2 nO- n: 1~10 integer n _2: s represents an integer of 1 to 5: 0 or 1 t: 0 or 1)

Specific examples of the compounds represented by Chemical Formulas 2 to 5 are shown in Table 3 below.

[Table 3- (1)]

[0015]

[Table 3- (2)]

[0016]

[Table 3- (3)]

[0017]

[Table 3- (4)]

[0018]

[Table 3- (5)]

[0019]

[Table 3- (6)]

These reactive binder resin (R) and reactive CTM are optionally mixed to form CTL. CTM /
The mixing ratio of R is 1 to 60/10 by weight, preferably 5
˜50 / 10 weight ratio. At 5/10 or less, there are characteristics such as ionization potential and mobility of CTM, but CTMs are separated from each other and electric characteristics are not sufficient, resulting in insufficient sensitivity.
Accumulation of residual potential is confirmed. On the other hand, when it is 50/10 or more, sagging due to insufficient viscosity during coating film formation, and in some cases CT
Crystallization of M occurs, and the coating film has high hardness, but on the other hand, it is brittle, the impact resistance is lowered, and peeling due to dents occurs, which is not preferable. A conventionally known binder resin may be mixed with the CTL. Polycarbonate and polyester are particularly preferable as such a resin.

Reactive CT with reactive binder resin (R)
2,5-dimethylhexane 2,5 as a reaction initiator of M
-Dihydroperoxide, dicumyl peroxide,
Benzoyl peroxide, t-butylcumyl peroxide, peroxide such as 2,5-dimethyl-2,5-di (peroxybenzoyl) hexyne-3, azo-based such as azobisisobutylnitrile or photo-curing initiator As Michler-ketone, benzoin isopropyl ether,
A ketone system such as 1-hydroxycyclohexyl phenyl ketone is used. The amount of addition is about 0.005 to 0.5 part by weight with respect to the monomer, and it is dissolved in a solvent at the above ratio to form a coating liquid.

Examples of the solvent include alcohols such as methanol, ethanol, propanol and butanol, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, ester such as ethyl acetate and butyl acetate, tetrahydrofuran, dioxane and propyl ether. Ether type, halogen type such as dichloromethane, dichloroethane, trichloroethane and chlorobenzene, aromatic type such as benzene, toluene and xylene, methyl cellosolve, ethyl cellosolve,
Examples thereof include cellosolve type such as cellosolve acetate. As a coating method, the above composition is added to the solvent at a concentration of 1
A construction method such as a dipping method, a spray method, or a roll method in which 0 to 70% is dissolved is applied.

In the present invention, the reactive CTM and another CTM are used.
You may use together. Examples of such CTMs include oxazole derivatives and oxadiazole derivatives (JP-A-52)
-139065, 52-139066),
Benzidine derivatives (described in JP-A-58-32372), α-phenylstilbene derivatives (JP-A-57-7)
No. 3075), hydrazone derivatives (Japanese Patent Laid-Open No. Sho 5)
5-154955, 55-156954, 55-520
63, 56-81850), triphenylmethane derivative (described in JP-B-51-10983), anthracene derivative (described in JP-A-51-94829), styryl derivative (described in JP-A-56- 2924
5, 58-198043), carbazole derivatives (described in JP-A-58-58552), pyrene derivatives (described in JP-A-2-94812), and the like. The CTL film thickness is 10 to 100 μm, and preferably 15 to 30 μm.

CGL is formed of CGM alone or CGM and a binder resin and has a film thickness of 0.02 to 3 μm.
m, preferably 0.05 to 1 μm. As the CGM, for example, CI Pigment Blue 25 (C.I.
No. 21180), CI Pigment Red 41
(CI No. 21200), CI Eye Acid Red 52 (CI No. 45100), CI Basic Red 3 ((CI No. 45210), a phthalocyanine pigment having a porphyrin skeleton, an azurenium salt pigment. , Squalic salt pigments, azo pigments having a carbazole skeleton (JP-A-53-95033), azo pigments having a stilbene skeleton (JP-A-53-138229),
Azo pigment having a triphenylamine skeleton
-132547), an azo pigment having a dibenzothiophene skeleton (JP-A-54-21728), an azo pigment having an oxadiazole skeleton (JP-A-54-12742), an azo pigment having a fluorenone skeleton (JP-A-54-228).
34), azo pigments having a bisstilbene skeleton (JP-A-54-17733), azo pigments having a distyryl oxadiazole skeleton (JP-A-54-2129), azo pigments having a distyryl carbazole skeleton (JP-A-54-129). 54-1
7734), a trisazo pigment having a carbazole skeleton (JP-A-57-195767, 57-195768),
Azo pigments having an anthraquinone skeleton (JP-A-57-2
02545), and C.I. I. No. Condensed polycyclic quinone compounds such as 59300 Vat Orange 3, C.I. I. N
o. Perylene compounds such as 38001, selenium and selenium alloys, a-silicon and the like can be used as the charge generating material.

These charge generating materials are crushed and dispersed by a ball mill or an attritor. The solvent used is cyclohexanone, methyl ethyl ketone, tetrahydrofuran, dioxane, butyl acetate, toluene, cellosolve, etc., and the average particle size is 0.5 μm or less. When the binder resin is used in combination, polyvinyl butyral, ethyl cellulose, epoxy resin, polycarbonate, polyester, polymethylmethacrylate, polyurethane resin or the like can be used as the binder resin, and the ratio of the charge generating material (P) to the binder resin (R) is P / R = 100/0 to 200, preferably 100/10 to 100. Then, is coated by a dipping method, a spray method, a roll coating method, or the like so as to have the above-mentioned film thickness. Alternatively, it can be formed by a vapor deposition method, a CVD method, a sputtering method, or the like.

The photosensitive layer is formed into a film-shaped or cylindrical plastic, paper or the like by vapor deposition or sputtering by metal such as aluminum, aluminum alloy, nickel, chromium, nichrome or copper, metal oxide such as tin oxide or indium oxide. Coated or aluminum,
Aluminum alloy, nickel, stainless steel, etc. plates and D. I. , I. I. Provided on a conductive support such as a tube formed by a method such as extrusion or drawing, or a tube which is surface-treated by cutting or polishing after forming the tube. that time,
An intermediate layer may be provided for the purpose of improving adhesiveness and preventing charge injection. As the intermediate layer, a resin layer such as polyamide, polyurethane, silicone resin, phenol resin, aldehyde-melamine resin, polyvinyl alcohol, polyvinyl butyral, polyacrylanilide, vinyl chloride-vinyl acetate-maleic acid copolymer, or these resins. S in
iO ₂ , Al ₂ O ₃ , ZnO, TiO ₂ , ZnS, Zr
A dispersion of pigment particles such as O ₂ , SnO ₂ and In ₂ O can also be used as the intermediate layer. The thickness of these intermediate layers is 0.05 to 20 μm, preferably 0.1 to 1
It is 0 μm.

[0027]

[Synthesis Example of Polycarbonate Resin Shown by Chemical Formula 1]

Synthesis Example 1 While flowing dry nitrogen gas into a reaction tank equipped with a stirrer, a thermometer, a gas introduction pipe, and a reflux condenser, 53 parts of a 48.5% caustic soda aqueous solution, 242.8 parts of water, and 2,2-bis (3-allyl-4-hydroxyphenyl) propane 66
Parts were charged and dissolved. This solution was cooled to 20 ° C., and 27.6 parts of phosgene gas was blown thereinto over 1 hour while stirring vigorously. Then 48.5% caustic soda solution 8.
After adding 9 parts and further adding 9.96 parts of p-tert-butylphenol as a reaction terminator, 0.97 part of triethylamine was added and stirring was continued at 30 ° C. for 2 hours. After completion of the reaction, the methylene chloride phase was separated, washed with water, acidified with hydrochloric acid and then washed with water repeatedly to remove dissolved salts. Thereafter, methylene chloride was removed by evaporation at 50 ° C at the following temperature to obtain a polymer (yield 99%). The specific viscosity of a solution obtained by dissolving 0.7 g of the obtained polymer in 100 ml of methylene chloride and measuring at 20 ° C. was 0.369. This one is methylene chloride,
It was soluble in chloroform, toluene, tetrahydrofuran and the like.

Synthesis Example 2 The apparatus used in Synthesis Example 1 was processed in the same manner as in Synthesis Example 1 to 48.5.
% Caustic soda aqueous solution 53.7 parts, water 230.8 parts,
2,2-bis (3-allyl-4-hydroxyphenyl)
31.3 parts of propane and 27.3 parts of 1,1-bis (4-hydroxyphenyl) cyclohexane were charged and dissolved. To this solution was added phosgene gas in the same manner as in Synthesis Example 1.
6.2 parts were blown in over 1 hour. Then 48.5%
After adding 8.4 parts of caustic soda aqueous solution and 0.61 part of p-tert-butylphenol, triethylamine 0.0
5 parts was added and stirring was continued for 2 hours. After the completion of the reaction, the same treatment as in Synthesis Example 1 was performed to obtain a polymer having a specific viscosity of 0.406 (yield 99%). This one is methylene chloride, chloroform,
It was soluble in toluene, tetrahydrofuran and the like.

Synthesis Example 3 Using the apparatus used in Synthesis Example 1, 1,1-bis (4-hydroxyphenyl) cyclohexane 27.3 of Synthesis Example 2 was used.
A polymer having a specific viscosity of 0.413 was obtained by treating in the same manner as in Synthesis Example 2 except that 26.0 parts of 2,2-bis (3-methyl-4-hydroxyphenyl) propane was used instead of parts. Rate 98%). This product was soluble in methylene chloride, chloroform, toluene, tetrahydrofuran and the like.

The copolymers shown in Table 4 below were synthesized in the same manner as in Synthesis Example 2 to obtain a copolymer having a specific viscosity of 0.370 to 0.470.

[Table 4]

Example 1 An undercoat layer coating solution having the following formulation was applied to Al having a diameter of 80 mm and 340 mm by a dipping method and dried at 120 ° C. for 10 minutes to form an undercoat layer of 0.3 μm. Undercoat layer coating liquid Polyamide resin (CM-8000, manufactured by Toray Industries, Inc.) 100 g Methanol 1200 g n-Butanol 1200 g Next, the following charge generation layer coating liquid was applied onto the above-mentioned undercoat layer and dried at 120 ° C for 10 minutes. Then, a charge generation layer having a thickness of 0.3 μm was provided. Charge generation layer coating liquid

[Chemical 6] Cyclohexane 250 g Methyl ethyl ketone 250 g After pulverizing and dispersing the above formulation in a ball mill for 72 hours,
Methyl ethyl ketone (500 g) was added and the mixture was dispersed again for 3 hours, and the resulting mill base was let down with a mixed solvent of 250 g of cyclohexanone and 250 g of methyl ethyl ketone to obtain a coating liquid. Then, the following charge transfer layer coating liquid was applied onto the charge generation layer by a dipping method and dried at 130 ° C.
The CTL is cured by the photo-curing device shown in Fig.
TL was provided. Charge transfer layer coating liquid

[Chemical 7]

[Chemical 8] Tetrahydrofuran 3000 g Silicon oil (KF-50 manufactured by Shin-Etsu Chemical Co., Ltd.) 0.06 g A photoreceptor was prepared as described above.

Examples 2 to 3 Except that the CTM and binder resin shown in Table 5 were used,
Photoreceptors of Examples 2 and 3 were prepared in the same manner as in Example 1. The results are shown in Table 5.

Example 4 In the same manner as in Example 1, an undercoat layer and CGL were provided, the following charge transfer layer liquid was applied by a dipping method, and dried at 130 ° C. for 30 minutes.
After curing, a CTL having a film thickness of 23 μm was provided. No. 3 in Table 3 Compound of 15 300 g Binder resin of Synthesis Example 4 300 g Benzoyl peroxide (solid content 50% paste) 5 g Silicon oil (KF-50 manufactured by Shin-Etsu Chemical Co., Ltd.) 0.06 g Toluene 3000 g

Examples 5 to 6 An undercoat layer and CGL were provided in the same manner as in Example 4, and 300 g of CTM of Examples 5 and 6 shown in Table 5 above and 300 g of binder resin were used instead of 300 g of the cured CTL to obtain a photosensitized CTL of 23 μm. Created the body.

Comparative Example 1 Similar to Example 1, an undercoat layer and a charge generation layer were provided, and the following charge transfer layer liquid was applied by the dipping method, dried at 130 ° C. for 30 minutes and dried to a thickness of 23 μm. Was established.

[Chemical 9] PC-A (Polycarbonate A resin C-1400 manufactured by Teijin Chemicals) 300 g Silicone oil (KF-50 manufactured by Shin-Etsu Chemical Co., Ltd.) 0.06 g Methylene chloride 3000 g

Comparative Example 2 300 g of the binder resin PC-A of Comparative Example 1 was added to PC-
Comparative Example 1 except that 300 g of Z (1,1-cyclohexylidene 4,4'-diphenyl carbonate) resin was used instead.
A photoconductor was prepared in the same manner as in.

Comparative Example 3 A photoconductor was prepared in the same manner as in Comparative Example 1 except that 300 g of the binder resin PC-A of Comparative Example 1 was replaced with 300 g of the binder resin of Synthesis Example 2.

The photocuring of Examples 1 to 3 was carried out by the photocuring device shown in FIGS. The photoconductor drums in the figure are installed on a support stand on the belt conveyor, and the support stand is 10 rpm.
Belt conveyor traveling speed 1m while rotating at the speed of
/ Min to move through the lamp house.
Four lamps with a mercury lamp output of 120 W / cm are used in the lamp house.
It is installed at a distance of 10 cm from the photoconductor drum, and an exhaust fan is provided on the top. After the CTL is light-cured, the arm is detached from the support. The prepared photoconductor is used in Japanese Patent Laid-Open No. 60-
Installed in the device shown in No. 100167, 1000
Rotate to rpm, discharge negative 6Kv voltage in the dark,
Obtain the potential (Vm) when applied for 20 seconds, then stop the discharge and perform dark decay for 20 seconds, then the potential (Vo) at that time, and further, the tungsten light quantity 26 Lux, slit width 6 mm
Sensitivity was determined by setting the amount E1 / 2 that is halved from Vo and the amount that becomes 1/10 by E1 / 10. The potential after 20 seconds was set to Vr. These photoconductors are manufactured by Ricoh Co., Ltd. F
It was mounted on T-4820 and subjected to a durability test of 100,000 sheets. The initial dark area potential (VD) is 800V, and the light area potential (V
L) was set to 80V.

[0039]

[Table 5]

[0040]

As is clear from Table 5, the electrophotographic photosensitive member of the present invention has a small amount of wear, is not accompanied by image deterioration, is excellent in mechanical strength, and has high sensitivity and high durability. ..

[Brief description of drawings]

FIG. 1 is a CTL layer forming apparatus preferably used in the present invention.

FIG. 2 is an enlarged view of the inside of the lamp house of the CTL layer forming apparatus preferably used in the present invention.

Claims (1)

[Claims] 1. An electrophotographic photosensitive member comprising a conductive support and a charge generation layer and a charge transfer layer laminated in this order, wherein the charge transfer layer contains a polycarbonate resin represented by the following chemical formula 1. A charge transfer material having a bond,
An electrophotographic photoreceptor characterized in that a charge transfer layer is formed by reacting with heat or light energy. [Chemical 1] (In the formula, R ₁ and R ₂ are hydrogen, an alkyl group having 1 to 10 carbon atoms, an aryl group, R ₁ and R ₂ together form a ring,
n represents the degree of polymerization. )