JPS58181049A - Electrophotographic receptor - Google Patents

Abstract

PURPOSE:To enhance the adhesive property of a charge generating layer to a substrate, by adding a silane coupling agent to the layer. CONSTITUTION:A charge generating layer and a charge transferring layer are successively formed on an electrically conductive substrate. The charge generating layer contains a charge generating pigment, a binder resin and a silane coupling agent such as (HO)3Si(CH2)3SC(-)(NH2)2Cl(-) or H2NCH2CH2 NHCH2 CH2CH2Si(OCH3)3. The amount of the coupling agent to be added is about 1- 15wt% of the total amount of the pigment and the solid matter in the resin.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrophotographic photoreceptor, and more particularly to an electrophotographic photoreceptor having significantly improved sensitivity and durability. 0 Organic photoconductive substances such as polyvinyl carbazole, oxadiazole, and phthalocyanine have advantages such as non-pollution and high productivity compared to inorganic photoconductive substances such as selenium and cadmium sulfide, but they have low sensitivity and
It was difficult to put it into practical use. Therefore, several sensitization methods have been proposed, but it is known that an effective method is to use a functionally separated photoreceptor in which a charge generation layer and a charge transport layer are laminated on a substrate.

To explain such photoreceptors in more detail, first, the conductive substrate is a metal such as aluminum, brass, or stainless steel, or a polymer such as polyethylene terephthalate, polybutylene terephthalate, polyethylene, polypropylene, nylon, or polystyrene phenol resin. It is used by molding material such as hard paper into a cylindrical shape or by making it into a foil inside a film. In the case of insulators,
It is necessary to conduct conductive treatment, which can be done by impregnating it with a conductive substance, laminating metal foil, or vapor depositing metal.

The charge generation layer is made of azo pigments such as Sudan Red, Diane Blue, and Jenas Green B, Algol Yellow,
Quinone pigments such as helenquinone and intanslenbri 11 anthaviolet RRP, quinocyanine pigments, indigo pigments such as rylene pigments, indigo, and thioindigo;
Bis such as India First Orange Toner uses charge generating substances such as nzoimidazole pigments, 7 thalocyanine pigments such as steel phthalocyanine, quinacridone pigments, polyester, polystyrene, polyvinyl chloride, polyvinyl acetate, etc.
Acrylic, polyvinylpyrrolidone, methylcellulose,
It is formed by dispersing it in a binder resin such as hydroxypropyl methylcellulose or polyvinyl butyral and coating it on a substrate.

The charge transport layer provided on the charge generation layer contains a polycyclic aromatic compound such as anthracene, pyrene, phenanthrene, coronene, or indole, carbazole, oxazole, isoxazole, thiazole, imidazole, pyrazole, or oxadiazole in the main chain or side chain. It is formed by dissolving a charge transporting substance such as a compound having a nitrogen-containing cyclic compound such as azole, pyrazoline, thiadiazole, or triazole, or a hydrazone compound in a film-forming resin. This is because the charge transporting substance generally has a low molecular weight and has poor film-forming properties by itself. Examples of such resins include polyester, polysulfone, polycarbonate, polymethacrylates, polystyrene, polyarylate, and the like.

Electrophotographic photoreceptors are basically #I between a substrate and a photosensitive layer, but improvements in adhesion between the substrate and the photosensitive layer, improvement in coatability of the photosensitive layer, protection of the substrate, covering defects on the substrate, An undercoat layer may be provided between the substrate and the photosensitive layer in order to protect the photosensitive layer from electrical damage and improve charge injection from the substrate to the photosensitive layer.

Lower eF@Fi Conventional materials include polyvinyl alcohol, polyvinyl methyl ether, poly-N-vinylimidasol,
Polyethylene oxide, ethyl cellulose, methyl cellulose, ethylene-acrylic acid copolymer, casein,
Polyamide, glue, gelatin, etc. are known. The film thickness is about 1 to 10 μm.

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However, on the other hand, it is difficult to obtain materials with sufficiently satisfactory properties, and the number of coating steps increases, resulting in an increase in manufacturing steps and an increase in production control items, which increases costs. Ninth, methods of manufacturing photoreceptors without forming an undercoat layer have also been studied.

The present invention aims to form a photosensitive layer on a conductive substrate without forming an undercoat layer.If the wettability and adhesiveness of the charge generation layer to the substrate are improved, the undercoat layer In order to improve this, in the present invention, a silane coupling agent is added to the charge generation layer.

Examples of the silane coupling agent include the following compounds.

2, H2NCH2CH2NHCH2CH2CH25
i(OCp5)55, CH2CHeH20CH2
CH7CH2Si(OCH3)5\0'& H8CH2CH2CH25i(QC)(5)5
7, CH35i(OCH5)5 a C'H2=C)isi(OOCCH5)5
9. (CHI)3SiN81(CR2)s These have two different types of blind functional groups in the same molecule (7. They act as a nakadashi between the organic resin and the inorganic substance, and the inorganic - The silane coupling agent to be used needs to be selected optimally depending on the material of the substrate and the type of binder resin.

The silane coupling agent may be added before or after dispersion into the pigment resin (.

The amount added is 1 to the total of the pigment and the tjAW content of the resin.
It is appropriate to set the weight to 15 degrees.

Adding a silane coupling agent after dispersing the charge generation layer improves the adhesion between the substrate and the charge generation layer;
As an unexpected result, we also found that sensitivity improved, albeit slightly. This is probably because the charge injection property from the substrate to the charge generation layer became better due to the improved adhesion.

Hereinafter, the present invention will be explained in more detail using specific examples.

Example 1 An aluminum cylinder of 80φ x 300m was used as a base.

β-type copper phthalocyanine compound (manufactured by Toyo Ink ■) was purified by successive hot filtration with water, ethanol, and methyl ethyl ketone. 10 parts by weight of this pigment was mixed with 100 parts by weight of 5-cyclohexano/# solution of linear polyester resin (trade name: Byron 300 manufactured by Toyobo ■), and then heated in a sand mill using 1φ glass beads for 5 hours. I was all separated.

1 part by weight of the silane coupling agent of Compound Example 8 and 80 parts of methyl ethyl ketone were added to the dispersion, and the mixture was coated onto a substrate by a dipping method. The bales were dried at 100° C. for 5 minutes and left at room temperature for 1 hour. In this way, a charge generation layer with a coating weight of 180q/I2 was formed.

Next, 1-[pyridyl-(2))-3-(4-N,
N-diethylaminostyryl) -5-(4-N,N-
10 parts of (diethylaminophenyl) pyrazoline and 10 parts of polysulfone resin (trade name Newdel PI70 [], manufactured by OCC) were dissolved in 80 parts of monochlorobenzene, and this solution was applied onto the charge generation layer by a dipping method and heated at 100°C.
Dry with hot air and mourn. At this time, a 12 micron thick charge transport layer was formed.

The thus produced electrophotographic photoreceptor was subjected to -5,6 KV corona charging, image exposure, dry toner current, toner transfer to plain paper, urethane rubber blade (hardness 70'', pressure 10
gv/m and an angle 2r:f) with respect to the photoreceptor, and the characteristics were evaluated by attaching it to an electrophotographic copying machine having a cleaning process. The sensitivity was measured to be 11.0 lux orders, and very clear images were obtained. This photoreceptor is 100
When the durability test was repeated with 0 sheets, the sensitivity #i was 11.5 lux·sec, and when the adhesion was examined by the cross-edge method after the durability test, it was 109Aoo and there was no peeling.

For comparison, an electrophotographic photoreceptor was manufactured by forming a charge generation layer in the same manner without adding a silane coupling agent. The sensitivity of this photoreceptor was measured to be 11.4 lux·sec.

When performing a similar durability test and determining the sensitivity, it is 12
．． It was 8 lux·sec, indicating deterioration.

Further, when the adhesion was examined, it was 30/'1oO, indicating that the adhesion was weak.

Example 2 In Example 1, the binder resin of the charge generation layer was changed to polyurethane resin (product name: Frisbon 5816, manufactured by Dainippon Ink ■), the silane coupling agent was changed to that of Compound Example 6, and the other things were the same. Manufactured in The sensitivity of the photoreceptor was measured to be 11.2 lux·sec, and after the durability test it was 11.2 lux·sec.
．． 4 lux·sec, and the adhesion Fi was 100/1oo.

Claims (1)

[Claims] A laminated electrophotographic photoreceptor in which a charge generation layer and a charge transport layer are formed in this order on a conductive substrate, wherein the charge generation layer contains a charge generation pigment, a binder resin, and a silane coupling agent. An electrophotographic photoreceptor characterized by: