JP2823885B2 - Function-separated organic electrophotographic photoreceptor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention provides a function-separated type having at least a phthalocyanine charge generation layer and a charge transport layer on a conductive support, which can easily provide desired photosensitivity. It relates to an electrophotosensitive member.

(Prior art and its problems) In an electrophotographic photoreceptor, an electrostatic latent image is formed by image exposure on the surface of a photoreceptor charged positively or negatively by corona discharge in a dark place as a copying process. Thereafter, a process of visualizing the latent image by toner development is performed. On the other hand, as shown in FIG. 1, a charge generation layer (2) containing at least phthalocyanine is formed on the surface of the conductive support (1), and a charge transport layer (3) is further formed thereon. The charge generation layer (2) in the organic electrophotographic photoreceptor generates electrons and hole carriers by absorbing light during image exposure, and the charge transport layer (3) transfers the generated electrons and hole carriers. It moves to the surface of the photoreceptor and plays a role of forming an electrostatic latent image corresponding to image exposure on the surface.

By the way, a conventional function-separated organic electrophotographic photosensitive member used for near-infrared wavelength region light such as a semiconductor laser is manufactured by the following method.

That is, as a material for forming the charge generation layer, for example, simply one type of phthalocyanine selected from column A of Table 1 and a binder (binder resin) selected from column B of Table 1 according to required photosensitivity. And further dispersed in one type of organic solvent selected from column C of Table 1 to obtain a wire bar,
It is made by applying using a doctor blade, spinner, dipping, spraying, etc., and then drying. However, since the photosensitivity of the photoreceptor produced by such a method is a constant photosensitivity which is substantially determined by the type of phthalocyanine used, the type of phthalocyanine used is changed every time the wavelength of the exposure light source used is different. Must be manufactured. Further, in this case, the given light sensitivity does not always coincide with the light sensitivity required by the exposure light source to be used, which may cause problems in image quality such as thickening or thinning of characters and resolution.

Of course, the photosensitivity is not uniquely determined by the phthalocyanine used, but can be changed by changing the type of binder resin or organic solvent used in the case of the dispersion method as is well known. However, the types of binder resins and organic solvents that can be used are considerably restricted due to the relationship with the charge transport layer formed on the charge generation layer, and it is difficult to actually meet the requirements.

In the case of the vacuum deposition method, for example, by changing the type of phthalocyanine selected from Table A, column A,
Also, the photosensitivity can be changed by changing the type of the organic solvent used for stabilizing the characteristics, for example, selected from column B of Table 2 and changing the crystal form of phthalocyanine by contact with the vapor. However, this method only shifts the light sensitivity provided by the phthalocyanine used, and it is difficult to provide the light sensitivity required by the exposure light source.

(Object of the Invention) It is an object of the present invention to provide a photoreceptor having the photosensitivity required by an exposure light source, in particular, a functional separation having a photosensitivity required by a near infrared wavelength light source such as a semiconductor laser or a light emitting diode array. Organic electrophotographic photoreceptor.

(Means of the Present Invention for Solving the Problems) In the present invention, indium phthalocyanine and titanyl phthalocyanine which have different photosensitivity alone are used as the material for forming the charge generation layer. Then, as shown in FIG. 2, the composition is changed by changing the compounding amounts of phthalocyanine A and phthalocyanine B, and the charge generation layer is formed on a conductive support by a dispersion method or a vapor deposition method in the same manner as in the related art. It was made clear that the light sensitivity of the photoreceptor can be changed from low sensitivity to high sensitivity in the near infrared wavelength region,
In this way, a photoreceptor having the light sensitivity required by the exposure light source used can be easily obtained.

 Next, the present invention will be specifically described with reference to examples.

〔Example〕

Indium phthalocyanine (InClPc) and titanyl phthalocyanine (TiOPc) were shaken with 0,20,40,60,80,100% by weight of indium phthalocyanine relative to the total amount, and each was shaken on an aluminum support under a vacuum of 2 × 10 ^-6 torr. About
After vapor deposition at 800 ° C., a charge generation layer in which the deposited layer was immersed in an ethanol solution and a charge generation layer in which the deposited layer was not immersed in an ethanol solution were formed.

Then a polycarbonate 30 on each charge generation layer
Parts by weight, a solution prepared by dissolving 25 parts by weight of P-diethylaminobenzaldehyde (diphenylhydrazone) in 250 parts by weight of chloroform is applied by spin coating, and dried at 80 ° C. for 2 hours to form a 20 μm charge transporting layer. The body was made.

This photoreceptor is charged negatively to 600V and monochromatic light (780nm)
When evaluating the incident exposure half amount E a, the third view of the solvent treatment of ethanol in a range of indium 0-40 wt%, such as those can be varied E ₅₀ until 2~6erg / cm ^2, It shall not in contact with the solvent can alter the E ₅₀ to 4~6erg / cm ^2. Therefore, by changing the content of indium phthalocyanine, a photoreceptor having an arbitrary photosensitivity can be manufactured.

In the above embodiment, the conductive support is made of aluminum, but may be made of nickel, copper, tin, stainless steel or the like. As the charge transport layer, other substances such as a hydrazone derivative, a pyrazoline derivative, and an oxadiazole derivative are used as well as a polymer substance. In the above description, the negative charge type is described. However, the positive charge type can be used according to the application, and the charge generation layer and the charge transport layer are formed accordingly. Further, an adhesive layer and a barrier layer may be provided as necessary. According to experiments, the thickness of the charge generation layer of the present invention was
The thickness is 0.05 to 1 μm, preferably 0.1 to 0.5 μm, and in the case of a vapor deposition method, it is 0.01 to 0.5 μm, preferably 0.03 to 0.3 μm.

(Effects of the Invention) As described above, according to the present invention, by mixing indium phthalocyanine, titanyl phthalocyanine, and charge generating layers having different photosensitivity into a charge generating layer to change the composition, an arbitrary photosensitivity can be obtained within a certain photosensitivity range. Thus, a photosensitive member having excellent image quality can be provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of the structure of a functionally separated organic electrophotographic photoreceptor.
FIG. 2 is an explanatory view of the present invention, and FIG. 3 is an explanatory view of one embodiment of the present invention. (1) ... conductive support, (2) ... charge generation layer,
(3) ... charge transport layer.

Continued on the front page (72) Inventor Kenichi Fujimori 1014 Miyaharacho, Kofu City, Yamanashi Prefecture Inside Yamanashi Electronics Industry Co., Ltd. (72) Inventor Masahiro Horikome 1014 Miyaharacho, Kofu City, Yamanashi Prefecture Yamanashi Electronics Industry Co., Ltd. (72) Invention Person Masakazu Kato 550-5 Higashiasakawa-cho, Hachioji-shi, Tokyo (72) Inside Oki Electric Industry Co., Ltd. (72) Inventor Kazumi Kawamura 550-5 Higashiasakawa-cho, Hachioji-shi, Tokyo Oki Electric Industry Co., Ltd. (72) Inventor Kenzo Tsuji 550-5 Higashiasakawa-cho, Hachioji-shi, Tokyo Oki Electric Industry Co., Ltd. (56) References JP-A-62-106465 (JP, A) JP-A-61-181867 (JP, A) JP-A 1-163749 (JP) JP, A) JP-A-2-84661 (JP, A) JP-A-59-116755 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G03G 5/06 371

Claims (1)

(57) [Claims] 1. A function-separated organic electrophotographic photosensitive member having at least a charge generation layer and a charge transport layer on a conductive support, wherein the charge generation layer contains indium phthalocyanine and titanyl phthalocyanine. Function-separated organic electrophotographic photoreceptor.