JPS6333747A - Electrophotographic materials - Google Patents

Abstract

PURPOSE:To obtain the titled material having improved flexibility and sticking property against a substrate by incorporating an org. photoconductive substance and a phenoxy resin to the titled material. CONSTITUTION:The titled material contains the org. photoconductive substance and the phenoxy resin. The electrophotographic sensitive body is formed by coating a substrate body which is composed of a polyester film and has a deposited layer of In2O3, with a solution A, followed by drying it with a hot air to remove a solvent contd. in the solution A, thereby forming an electric charge generating layer having 1mum thickness, and subsequently by coating said layer with the solution B, followed by similarly, removing the solvent contd. in the solution B, thereby forming an electric charge transfer layer having 20mum thickness. Said solution A is formed by mixing 3g of copper phthalocyanine, 2g of the phenoxy resin, 1g of polyisocyanate and 70g of a mixture of MEK/toluene (1/1), and by dispersing the obtd. mixture for 24hr. Said solution B is formed by dissolving 2g of polycarbonate and 2g of diphenyl hydrazone derivative in 10g of THF. Thus, the titled material having an excellent flexibility and very good sticking property against the substrate body, and capable of preventing a lowering of a photosensitivity is obtd.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention provides an electrophotographic photosensitive material that has excellent phototransferability and adhesion to a conductive support without reducing dark resistance or photosensitivity. Regarding materials.

[Conventional technology]

Conventionally, many materials are known as inorganic and organic photoconductive materials for electrophotographic photosensitive materials.

Inorganic photoconductors such as zinc oxide, selenium, lubrication, and cadmium sulfide have excellent properties in terms of photosensitivity, but have problems in transparency, lightness, flexibility, and pollution resistance.

On the other hand, organic photoconductive materials, compared to inorganic materials,
Many more substances are known, and examples of low-molecular organic photoconductive substances include various metal phthalocyanines,
Metal-free phthalocyanines, oxadiazole conductors, benzimidazole derivatives, etc. are also disclosed as polymer-type organic photoconductive substances, for example, in Japanese Patent Publication No. 18674/1982 and Japanese Patent Publication No. 25230/1989. Polymers containing heterocyclic rings such as carbazole rings, or polynuclear aromatic rings such as naphthalene rings and anthracene rings are known.

[Problem to be solved by the invention]

These organic photoconductive materials have excellent transparency, light weight, and non-polluting properties as organic materials, but their photosensitivity is significantly lower than that of inorganic materials, and further improvements in physical properties are required. Ninth, there is much to be done.To date, photoconductive materials have been considered inferior in practicality to inorganic photoconductive materials. Regarding the former photosensitivity, advances in organic synthesis technology have led to the disclosure of useful organic photoconductive substances and sensitizers, and their practical measurement has rapidly increased. There are many problems regarding the physical properties of organic photoconductive materials, which pose a major obstacle to the practical application of organic photoconductive materials. For example, polymer-type organic photoconductive materials have strong intermolecular cohesive forces, often crystallize, impairing transparency, and are generally hard and brittle, and unfortunately have poor adhesion to supports. It has the following disadvantages. For low-molecular-weight organic photoconductive substances, vapor deposition, dispersion or dissolution in resin, etc. are used to form the entire photosensitive layer, but in the case of vapor deposition, adhesion to the flexible support is Furthermore, there are problems with ink effectiveness and cost when forming a photosensitive layer, and when dispersing or dissolving in a resin, flexibility,
The adhesion with the support is almost determined by the properties of the resin that is the binder, but the resins currently used cannot be said to have sufficient visibility or adhesion with the support. Even if the properties were good, they were accompanied by effects such as a decrease in surface potential and a decrease in photosensitivity, which completely impaired the desired electrophotographic properties, and did not give satisfactory results.

The present invention is intended to solve the above-mentioned problems, and its purpose is to produce an electronic photoreceptor that has excellent flexibility and adhesion to the support without degrading the electrophotographic photoreceptor. The company provides photographic materials.

[A precautionary measure to solve the problem]

The electrophotographic light-sensitive material according to the present invention includes an organic light-emitting substance,
And, it is characterized by containing a phenoxy resin.

[Example-1] Copper phthalocyanin
e BlueIJB ()K Sumitomo Chemical) 5? , phenoxy resin (STX-0 Ototobu Kasei) 2f1 polyinsyanate (Japan Polyurethane) 12, methyl ethyl ketone (hereinafter referred to as MKK)/) luene (=1/1) 70? were mixed and dispersed in a ball mill for 24 hours, and this was defined as kAi.

Polycarbonate (N0VAREX, Mitsubishi Kasei) 2? ,
Diphenylhydrazone conductor (CTC-256, Asan Fragrance Industry) 2? is tetrahydrofuran (hereinafter Tl (F'
) 109, this is t-B! shall be. Polyester film with a vapor-deposited layer (high beam 100
L-BK (12, east) T-support and shite, ha
was coated and dried with hot air to remove the solvent to form a charge generation layer with a thickness of 1 μm.Furthermore, Solution B was coated and the solvent gold was removed in the same manner to form a charge transfer layer with a thickness of 20 μm. This is referred to as the entire electrophotographic photoreceptor 1.

In addition, in liquid A, polyester resin (Vylon 20θ, Toyobo) was used instead of phenoxy resin.
An electrophotographic photoreceptor 10 is prepared by applying the same liquid instead of the above-mentioned liquid A and using this as a charge generation layer.

Table 1 shows the measurement results of visibility, adhesion to the support, and photosensitivity of electrophotographic photoreceptors 1 and 10.

The flexibility is due to the photoconductive layer (charge generation 1- and the layer 1 on top of it)
The photoconductive layer was wound around several types of cylinders with different diameters with the specific charge transfer layer on the outside, and the diameter was expressed as the diameter at which cracks occurred in the photoconductive layer. Practically, a value of 5H or less is required, preferably a value of 3211 or less.

The 'Xg adhesion to the support was evaluated by a cross-cut test, with no peeling at all, Δ if less than 1 cL1 peeled off, and gold × if peeling of 1% or more.

Photosensitivity was compared using an electrostatic copying paper tester (SP-428゜Kawaguchi Denki) using the amount of exposure until the initial surface potential was halved due to light attenuation (half-attenuation exposure).

[Example-2] Instead of copper phthalocyanine in AH of Example 1, metal-free 7
Using talocyanin (Dainippon Ink), prepare the same as liquid A, and use liquid D as liquid.

Example 1 Mr. Kan, D8! After coating on a polyester film having an os vapor deposited layer and drying, apply B liquid t.
- The photoconductive layer is coated to form a photoconductive layer having a structure in which a charge transfer layer is laminated on a charge generation layer. This electrophotographic photoreceptor is referred to as an electrophotographic photoreceptor 2.

In addition, in the D solution, polyvinyl butyral resin (S-LKCBM-2゜ Seishi Kagaku) t is used instead of phenoxy resin.
The electrophotographic photoreceptor 20 is prepared by using the used liquid as liquid E and applying the same in place of the above liquid to form the t-charge generation layer.

Table 1 shows the results of measuring the flexibility, adhesion to the support, and photosensitivity of α-child photographic elements 2 and 20.

[Example-3] Instead of the copper phthalocyanine of AM in Example 1, metal-free phthalocyanine (BhSy) was used. A liquid prepared in the same manner as A'KL was used as solution F, and in the same manner as in Example 1, gold 1
A polyester film having a vapor-deposited layer of N20B is coated and dried to form a charge generation layer.

Poly-N-vinylcarbazole (EASF) 3? Phenoxy resin (Phenotote YP-50, Tobu Kasei) 22
, polyisocyanate (Japan Polyurethane) 1 f,
Dissolved in t-THEP70 F, this? As liquid G, F′
Example 1 was applied on the charge generation layer formed by coating fL.
Liquid G is applied between liquid B to form a charge transfer layer, and this electrophotographic photoreceptor is referred to as electrophotographic photoreceptor 3.

9. In yW, polyvinyl formal resin (Denka Formal) is used instead of phenoxy resin.

In GO, polyester resin (Vylon 200. Toyobo) was used instead of phenoxy resin, and this was used as the H solution, and it was coated as sp'tW and sGG liquids, respectively. Then, the entire photoconductive layer is formed.
This will be referred to as an electrophotographic photoreceptor 60.

Table 1 shows the measurement results of the flexibility, close layering property with the support, and photosensitivity of the electrophotographic photoreceptors 5 and 30.

Table 1 [Effects of the Invention] From the results of Examples 1 to 3 (Table 1), it can be seen that the electrophotographic photosensitive materials (1 to 3 in the table) having the photoconductive layer according to the present invention are made of phenoxy resin Kanakura Compared to the secondary photographic light-sensitive materials (comparative examples, 10 to 50 in the table), it has excellent flexibility, very good layering properties with the support, and almost no decrease in photosensitivity. have

that's all

Claims (1)

[Claims] An electrophotographic photosensitive material containing an organic photoconductive substance and a phenoxy resin.