JPS5893062A - Electrophotogaphic photoreceptor - Google Patents

Abstract

PURPOSE:To improve sensitivity particularly in low humidity environment and the durability of a photoreceptor by adapting a mixed system of resins and org. metallic compds. to an undercoating layer. CONSTITUTION:A mixture of resins such as PVA, gelatin, casein, cellulose, polyacrylate or the like and org. metallic compds. such as Zn(CH3)2, Al(C2H5)3, B(C2H5)3, Ni(C2H5)2, Al[OCH(CH3)2]3, Ti(OC3H7)4 or ?metallic chelate compds. is used as an undercoating layer. The amt. of the org. metallic compds. to be added is suitably 1-50pts. based on 100pts. the resin.

Description

[Detailed description of the invention] The present invention relates to an improved laminated electrophotographic photoreceptor.

Polyvinylcarbazole, oxadiazole.

Organic photoconductive substances such as phthalocyanine are selenium.

Compared to inorganic photoconductive materials such as cadmila sulfide, it has advantages such as being non-polluting and durable, but its sensitivity is low, making it difficult to put it into practical use.Therefore, several sensitization methods have been proposed. However, it is known that an effective method is to laminate a charge generation layer and a charge transport layer and use a nine-functionally separated photoreceptor.

Charge generation layer Fi, % Sudan Red, Diane Blue,
Azo rhymes such as Jenas Green B, quinone pigments such as Algol Yellow, Pirene Kino/, and Indanthrene Brilliant Violet RRP, indigo pigments such as quinocyanine pigments, perylene pigments, indigo and thioindigo, and bisbenzimidazole compounds such as India First Orange Toner. Charge-generating substances such as 7-talocyanine pigments such as 7-talocyanine pigments, quinacridone pigments such as steel 7-alpha cyanine, and 7-talocyanine pigments such as 7-thalocyanine pigments such as steel 7-alpha cyanine are combined with charge-generating substances such as polyester, polystyrene, polyvinyl chloride, polyvinyl acetate, acrylic, polyvinyl butyral, polyvinyl pyrrolidone, methylcellulose, hydroxyglobil methylcellulose, etc. In the conventionally known case, the charge generation layer is formed by dispersing it in a binder resin and coating it on the substrate, but the charge generation layer is directly applied to the substrate. Regarding the coating method, it is preferable to provide one resin layer on the substrate and coat the charge generation layer thereon. This resin layer is generally an undercoat layer or
It is called an intermediate layer, and it improves the adhesion between the photosensitive layer and the substrate, improves the coating properties of the photosensitive layer, protects the substrate, covers defects on the substrate, protects the photosensitive layer from electrical breakdown, and protects the photosensitive layer from chiarization. This is provided for purposes such as improving injection properties. This material includes minerals, polyurethane, polyamide, polyvinyl alcohol,
Epoxyethylene-acrylic acid copolymer, ethylene-vinyl acetate copolymer.

Casein, methylcellulose, nitrocellulose, phenolic resin, etc. are known. However, the conventional undercoat layer has a drawback that sensitivity decreases in a low humidity environment of 1% S environment.

Therefore, the main object of the present invention is to provide an electrophotographic photoreceptor having an undercoat layer that solves the At deficiency.

The present invention improves characteristics by applying a mixed system of a resin and an organometallic compound, that is, increases sensitivity and lowers humidity by %! Environment Kj? The substrate is metal such as aluminum, brass, stainless steel, or polyethylene terephthalate or polybutylene terephthalate.

Insulators made of polymeric materials such as polyethylene, polypropylene, nylon, and polystyrene, and materials such as hard paper in the form of cylindrical or film foils require conductive treatment. Methods include impregnation, metal foil lamination, and metal vapor deposition. An undercoat layer made of a mixed system of resin and organometallic compound is applied onto these substrates. Here, the resin can be appropriately selected from those that are not eluted by the solvent of the charge generation layer. For example, polyvinyl alcohol, gelatin, casein, cellulose, polyacrylic acid, polyacrylate, polyarylate, polystyrene, polyvinyl chloride.

Polyvinyl acetate, polyvinylpyrrolidone, polyester, polyamide, polycarbonate, styrene-maleic acid copolymer, styrene-methyl acrylate copolymer,
Other various copolymer resin golds can also be used.

In addition, as the organometallic compound used in the present invention, s ”
(CHs)te” (”alm)t*A
j(CtHs)sy B(<'yHs)s.

Metal alkyl compounds A such as Nt (C's H5)t
j (0CR(CHa)x)s t Ti (0Cs
There are metal compounds such as Hv)+, and metal chelate compounds are also useful. Examples include acetoacetate chelate compounds such as chromium, vanadium, cobalt, and iron, ethylenediamine chelate compounds, and carbonyl chelate compounds. It will be done. Other organic carboxylic acid metal salts are also effective. These organometallic compounds are mixed with the above-mentioned resin and two suitable solvents to form a homogeneous solution or, if necessary, a dispersed state to form an undercoat layer coating solution. At this time, the dispersion method is roll mill, ball mill,
Use a method such as a sand mill.

The amount of the organometallic compound of the present invention to be added ranges from 1 to 50 parts per 100 parts of the resin. Coating thickness of undercoat layer: 0.5~
10μ is appropriate. A charge generation layer is formed on this undercoat layer. The charge generating layer is applied after dispersing the pigment described above in a binder resin.

The dispersion method involves dissolving the binder resin using an appropriate solvent, adding the pigment thereto, and dispersing by using a ball mill, vibrating ball mill, sand mill, roll mill, or the like. Coating thickness Vi0.
1-1μ is suitable.

The charge transport layer coated thereon contains a polycyclic aromatic compound such as anthracene, pyrene, phenanthrene, coronene, or indole in the main chain or side chain.

Carbazoles, oxazoles, isoxazoles, thiazoles, imidazoles, pyrazoles.

It is formed by dissolving a charge transporting substance such as a compound having a nitrogen-containing cyclic compound such as oxadiazole, pyrazoline, thiadiazole, or triazole, or a hydrazone compound in a resin that has film-forming properties. This is because charge-transporting substances generally have a low molecular weight and have poor film-forming properties by themselves. Examples of such resins include polyester, polysulfone, polycarbonate, polymethacrylate, and polystyrene. The thickness of the charge transport layer is 5 to 2
0 μ is appropriate. Next, specific examples will be shown and the present invention will be explained on all pages.

Example I 10 parts of N-methoxymethylated nylon resin was dissolved in 70 parts of methanol and 20 parts of toluene, and 2 parts of isopropoxyaluminum was added thereto to prepare an undercoat layer coating solution. The above coating solution was applied to an 80φ x 360m aluminum cylinder using a dipping method and dried by heating at 80°C for 10 minutes to obtain a film thickness of 2.
After forming the μ subbing layer, polyvinyl butyral resin (product name: Nislex 8M
-1, seed water chemistry IK) 5 parts 2 and cyclohexanone 40
1 part, 20 parts of methyl ethyl ketone, treated for 2 hours in a sand mill using 1φ glass beads to prepare a pigment dispersion.This liquid was applied by dip coating on the undercoat layer, and
A charge generation layer having a thickness of 0.2 .mu.m was formed by heating and drying at .degree. C. for 10 minutes.

Next, 1-[pyridyl-(2)]-3-
(4-N, N-diethylaminostyryl) 5 (4N,
A solution consisting of 10 parts of N-diethylaminophenyl) pyrazoline, 10 parts of polysulfone resin (trade name: Newdel P-1700, manufactured by Asa CC Co., Ltd.) and 70 parts of monochlorobenzene was applied by dipping and dried by heating at 100°C for 20 minutes to form a membrane. A charge transport layer having a thickness of 12 μm was formed. The obtained photoreceptor is referred to as photoreceptor-(1).

Example 2 1 part of ethylmethylcaptotricarbonyl iron was added to 50 parts of a toluene solution (resin content 20 wt%) of methyl methacrylate-n-butyl methacrylate copolymer (molar ratio 7/3) and subbing. 80φ x 360m for making layer coating solution
The above coating solution was applied to an aluminum sill by a dipping method and dried at 80°C for 10 minutes to form a subbing layer with a film thickness of 3μ. Product name: VMCH, UCC Co., Ltd.) 5 parts, 20 parts of yx-y-l x-y-le-keto y, and 40 parts of methyl isobutyl lactone were dispersed for 2 hours in a sand mill apparatus using 1φ glass beads. This liquid was applied onto the undercoat layer by dip coating and dried at 100° C. for 10 minutes to form a charge generation layer having a thickness of 0.15 μm.

Next, 12 parts of a hydrazone dye having the following structural formula and 10 parts of a polyarylate resin (trade name: V-100, manufactured by Unitika) were dissolved in 50 parts of monochlorobenzene and 50 parts of toluene, and this solution was dip-coated onto the charge generation layer. A charge transport layer having a thickness of 15 μm was formed. The obtained photoreceptor was photoreceptor-(1
) A comparative photoreceptor was prepared by forming each of the charge generation layer and charge transport layer in Example 4F41 without providing an undercoat layer on an aluminum cylinder.

Photoreceptors according to the present invention - (1), (1) and comparative photoreceptors -
5,6kV corona charging, image exposure, dry toner transfer, toner transfer to plain paper, urethane rubber blade (hardness 70
0, pressure 5gw151. Electrophotographic copying machine KJ &
The characteristics were evaluated.

As shown in Table IK, the initial sensitivity and the sensitivity after 3000 repeated durability tests show that the photoreceptor according to the present invention can be used in a low humidity and variable environment Ks? It is clear that there is no decrease in sensitivity and good durability even when the image quality is ◎ Also, good #I images were obtained even after repeated durability tests.

Applicant: Canon Co., Ltd.

Claims (1)

[Claims] 1. A laminated electrophotographic photoreceptor comprising an undercoat layer, a charge generation layer, and a charge transport layer on a conductive substrate, the undercoat layer comprising an organometallic compound and a resin.