JPS62272276A - Production of electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain a photosensitive layer having a barrier layer which is hard to produce a trouble about picture quality by coating a metallic substrate, with a solution of org. titanium compd. followed by calcining it in an oxidative atmosphere, thereby forming a layer composed of titanium oxide on the substrate, and subsequently, laminating a photosensitive layer on the obtd. layer. CONSTITUTION:At the time of producing the titled body, the org. titanium compd. is dissolved in a suitable solvent so as to control viscosity of the obtd. solution to that suitable for coating it, followed by coating the obtd. solution on the metallic substrate. The obtd. substrate is sufficiently dried to remove the solvent, followed by heat-treating the obtd. substrate at a prescribed temp. in the oxidative atmosphere, thereby forming a layer composed of titanium oxide having <=5mu thickness on the metallic substrate. And then, the photosensitive layer is laminated on the obtd. layer. Thus, the stable electric characteristic of the titled body is obtd, even in a changing surrounding. At the time of laminating the photosensitive layer on an upper layer of the titled layer, the titled body having the barrier layer which is hard to produce the trouble about the picture quality is obtd.

Description

[Detailed description of the invention] 3. Detailed description of the invention [Industrial usage rI] The present invention relates to a method for manufacturing an electrophotographic photoreceptor.

[Prior Art] In general, Carlson type electrophotographic photoreceptors require stability of dark area potential and bright area potential in order to form an image with constant image density and no background smudge when charging and exposure are changed to green. It has become important.

For this reason, it has been proposed to provide a layer that functions as a barrier layer between the photosensitive layer and the conductive layer. The layer functioning as such a barrier layer is also required to have good adhesion to the conductive layer and the photosensitive layer.

Until now, it has been known to use resins such as polyurethane, polyamide, polyvinyl alcohol, epoxy resin, casein, methylcellulose, phenolic resin, and nitrocellulose as a layer provided between the photosensitive layer and the conductive layer. When a photoreceptor using this layer is used with a green color, the bright area potential increases and the dark area potential fluctuates.Especially in a low humidity environment, when the photoreceptor is used with a green edge, the bright area potential increases and the dark area potential changes. This method has the disadvantage that it is not possible to produce copies with constant image quality under changing environments. Therefore, in order to eliminate these drawbacks, we created a film by applying a coating in which powders such as TiO2, ZnO, and carbon black were dispersed in polymer paints such as phenol resin, epoxy resin, and acrylic resin. A single-layer barrier with excellent potential stability was proposed, with little change in electrical properties such as resistance and capacitance even in harsh environments. However, even with the above barrier layer, problems such as environmental fluctuations in electrical properties mainly due to the resin used as a binder and deterioration of image quality due to paint dispersibility, coating properties, etc. tend to occur.

[Problems to be Solved by the Invention] An object of the present invention is to have a barrier layer that has stable electrical characteristics even under fluctuating environments and that does not cause problems in image quality even when a photosensitive layer is laminated thereon. An object of the present invention is to provide a method for manufacturing an electrophotographic photoreceptor.

[Means and Methods for Solving the Problems] The present inventor has achieved the above object by subjecting an organic titanium compound to oxidative thermal decomposition on a conductive substrate and providing a thin layer mainly composed of titanium oxide on the conductive substrate. The present invention was completed by discovering that the following can be achieved.

The present invention is characterized in that an organic titanium compound solution is applied onto a metal substrate, and then baked in an oxidizing atmosphere to form a layer mainly made of titanium oxide on the substrate, and a photosensitive layer is laminated as an upper layer on this layer. It consists of a method for manufacturing an electrophotographic photoreceptor.

As the organic titanium compound used in the present invention, basically any compound can be used as long as it is soluble in a solvent. Examples thereof include the following group of compounds known as titanium coupling agents.

Ti(0-iso-CxH7)+ Tetraisopropoxytitanium, Ti(0-n(:4Hs)4 Tetra-no
-Butoxytitanium, Ti(QCHzCH(CxHr)C
4I(514tetrakis(2-ethylhexoxy)titanium, ?1(OH)yo[0CH(CH+)COOHhdihydroxybis(lactato)titanium, T i (0-i 5o-03H7) (OCOf, 7
Hxr) 3isopropoxytitanium triisostearate.

T i (0-n-C4H9) [0C-J4N (C
:LH40H)z] Nidibutoxy-bis(triethanolaminato)titanium, ? 1(0-isa-C3H7)x
[0c(CH3)CHCOC:J]zdiisopropoxy bis(acetylacetonato)titanium, etc.

Note that the titanium coupling agent itself does not have adhesive properties, but when the surface of the object to be bonded is treated with a titanium coupling agent solution, the titanium coupling agent causes a hydrolysis-condensation reaction, resulting in surface adhesion. It is an agent that has the effect of improving sex.

As the conductive substrate used in the present invention, since it is heated at a high temperature in an oxidizing atmosphere, full-bending vapor-deposited plastics or conductively treated paper are not suitable, but metal drums or sheets made of aluminum, brass, copper, etc. are preferable.

In the present invention, in order to provide a layer mainly composed of titanium oxide, an organic titanium compound is dissolved in a suitable solvent such as toluene, methyl ethyl ketone, ethanol, etc., and after adjusting the viscosity to a suitable level for coating, Dip coating on top,
Apply by spray coating, roll coater coating, etc.

After that, after sufficiently drying to remove the solvent, a baking process of 500 to 1. Heat treatment is performed in air at a temperature of OOO'O.

Regarding the film thickness, a range of 0.5 to 5.0 is suitable; below 0.5 μl, pinholes are likely to form and defects on the substrate are likely to be reflected; , cracks and wrinkles are likely to occur on the surface after thermal decomposition.

The heating temperature is limited by the heat resistance of the metal used for the substrate, but a range of 500 to 1,000°C is generally suitable since thermal decomposition will not proceed if the temperature is low.

The photosensitive layer used in the present invention is not limited to a single layer type.
It is also possible to have a laminated structure in which the charge generation layer and the charge transport layer are separated in function. The charge transport layer is formed by coating and drying a dispersion in a resin such as acrylic resin. It is formed by applying a solution dissolved in a resin such as and drying it.

Examples of the single-layer type photosensitive layer include an inorganic photoconductive layer in which cadmium sulfide or zinc oxide is dispersed in a resin, a poly-N-vinylcarbazole or selenium vapor M layer, or an amorphous silicon layer.

The electrophotographic photoreceptor manufactured according to the present invention has wide application fields such as laser printers, liquid crystal shutter printers, and LED printers, in addition to being used in electrophotographic copying machines.

[Example] Example 1 An organic titanium compound having the following structure manufactured by Ajinomoto Co., Ltd.
Prepare a 50% ethanol solution of the product name Prenact TTS, and use a regular spray coating device to coat it with an outer diameter of 60 m.
m, length 250mm, wall thickness 1mm aluminum cylinder so that it is 5g/m2, then 1
After dry explosion at 00'O for 30 minutes, 550' in air atmosphere
Heated for 160 minutes.

When the surface was observed after cooling, it was confirmed that a dense white %FEt film having a film thickness of 1.2 was formed.

Next, (100 parts by weight of copper phthalocyanine (manufactured by Toyo Ink ■), butyral resin (trade name Kosurek BM, Jfi
(manufactured by Suikagaku ■) 50ilX parts and 1 part of cyclohexanone
350 i parts were dispersed for 20 hours in a sand mill using 1φ glass beads. Add 2700 g of methyl ethyl ketone to this dispersion, dip coat it onto the treated aluminum cylinder, and heat dry at 50"C for 10 minutes to form a charge generating layer with a coating weight of 0.15 g/m'2. Established.

Then, P-diethylaminobenzaldehyde-N-β
-10 parts of naphthyl-N-phenylhydrazone and styrene-methyl methacrylate copolymer (trade name MS-
200, manufactured by Seitetsu Kagaku ■) was dissolved in 80 parts of toluene. This solution was coated on the charge generation layer and 100%
It was dried with hot air for 1 hour at "C" to form a charge transport layer of 16jL.

In this way, an electrophotographic photoreceptor was manufactured.

Example 2 An organic titanium compound having the following structure, manufactured by Ajinomoto ■,
An electrophotographic photoreceptor was produced in the same manner as in Example 1, except that a 50% ethanol solution of 9S (trade name: Plenac) was prepared, and the solution was replaced with the ethanol solution of the organic titanium compound in Example 1.

Furthermore, in Examples 1 and 2, when the coating amount of the organic titanium compound solution was applied under conditions such that the film thickness after firing was 5 mm or more, many small cracks were generated on the film surface after firing. When images were produced using an electrophotographic photoreceptor manufactured by the company, the images were extremely defective.

Comparative Example Instead of the organic titanium compound solution used in the above example, a casein aqueous solution (10%) was applied and dried to form a barrier layer with a thickness of 2.0 l. after that,
A charge generation layer and a charge transport layer were formed in the same manner as in Examples to produce an electrophotographic photoreceptor.

The electrophotographic photoreceptor manufactured in the above example and the electrophotographic photoreceptor manufactured in the comparative example were each loaded into a laser beam printer equipped with a semiconductor laser with an oscillation wavelength of 788 nm, the Jllll constant environment was changed, and the photoreceptor was The results of measuring the surface potential are shown below.

Environment 23℃/60% VD/VL Example 1 Initial 710V/180V1.000
After sheet 710V/190V Example 2 Initial 700V/170V1.000
After sheet 690V/180V Comparative example Initial 710V/170V1.000
After sheeting 670V/120V Environment 35°C/80% V O/ V L Example 1 Initial 680V/150V1.000
After sheet 670V/140V Example 2 Initial 690V/150V1.000
After sheet 660V/120V Comparative example Initial 650V/120V1.000
After sheeting 550V150V Environment 15℃/10% V D / V L Example 1 Initial 720V/200V1.000
After sheet 720V/240V Example 2 Initial 720V/200V1.000
After sheet 690V/250V Comparative example Initial 720V/230V1.000
Post-sheeting 700V/340V As seen in the above results, the electrophotographic photoreceptor manufactured according to the example has a stable potential even when the temperature/humidity environment changes, and there is little potential variation even after repeated testing.

[Effects of the Invention] As described above, the method of the present invention provides an electrophotographic photosensitive material that has stable electrical characteristics under fluctuating environments and has a barrier layer that does not cause image quality problems even when photosensitive layers are laminated. The body could be manufactured easily.

Claims (2)

[Claims] (1) Applying an organic titanium compound solution onto a metal substrate,
A method for manufacturing an electrophotographic photoreceptor, which comprises: then firing in an oxidizing atmosphere, providing a layer mainly made of titanium oxide on the substrate, and laminating a photosensitive layer as an upper layer. (2) The method for producing an electrophotographic photoreceptor according to claim 1, wherein the layer mainly composed of titanium oxide has a thickness of 5 μm or less.