JPS5912443A - Electrophotographic receptor - Google Patents

Abstract

PURPOSE:To obtain an electrophotographic receptor giving superior image characteristics and having superior moisture resistance and high reproducibility by forming a photoconductive layer contg. a specified org. titanium compound by a specified amount basing on the amount of powder of a photoconductive material on a substrate. CONSTITUTION:A photoconductive layer is formed on an electrically conductive substrate by applying a photoconductive coating contg. an org. titanium compound represented by formula I or II [where R1O is (CH3)2CHO-, ROCOCH2O-, ROCH2CH2O- or CPH2P+1O- (1<=p<=10), R is H or CPH2P+1, each of R2 and R3 is a group represented by formula III, IV or V, -CH=CHX4 or the like, X4 is H, NH2 or SH, each of X1-X3 is -(C=O)-, a group represented by formula VI, VIIor VIII or -(SO2)-, each of (m) and (n) is 0-3, and m+n=2 or 3]. The titanium compound is incorporated by 0.01-3pts.wt. per 100pts.wt. photoconductive powder. A copied image of superior quality is obtd. even at high humidity.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrophotographic photoreceptor, and particularly to an electrophotographic photoreceptor that has excellent image characteristics, moisture resistance, and good reproducibility.

Generally, when manufacturing an electrophotographic photoreceptor using a photoconductive material powder, a photoconductive paint is prepared by dispersing the photoconductive material powder in a binder, and this is applied to an aluminum or other conductive substrate. '' to form a photoconductive layer. However, since these photoconductive materials are generally polar, they have poor wettability with binders and are difficult to disperse uniformly, making it difficult to create photoreceptors with good image properties and moisture resistance. In addition to being difficult to obtain,
There was a problem in that characteristics varied from lot to lot, making it impossible to obtain a homogeneous photoreceptor.

The present invention has been made in view of these problems, and an object of the present invention is to provide an electrophotographic photoreceptor that has excellent image characteristics and moisture resistance, and has good reproducibility.

The electrophotographic photoreceptor according to the present invention has the general formula; m −4
−n=2 or 3 is satisfied. ) is characterized in that a photoconductive coating containing an organic titanium compound represented by By appropriately adjusting the blending ratio in the photoconductive material powder, a coupling reaction with the photoconductive material powder imparts lipophilicity to the surface of the powder particles, improving wettability with the binder and at the same time facilitating dispersion. This is based on the knowledge that it improves sexual performance.

Specific examples of the organic titanium compound represented by the above general formula include isopropoxy tristearoyl titanium, impropoxy tricumylphenyloxy titanium, isopropoxy dimethacrylisostearoyl titanium, and isopropoxy isostearoyl diacryl titanium. , these may be used alone or in combination, but are not limited thereto. In addition, commercially available products include KR-TTS ((CI) manufactured by Kenrich Petrochemicals Co., Ltd.
(3) 2CHO--f' i (OCOCl 7H35
) Trade name of titanium coupling agent consisting of 3), KR-
348 [(CI(3)2CI(OTi(OC6H4C(
Examples include KR-7 and KR-11, as well as the trade name of a titanium coupling agent consisting of CH2)2-C6H5)3.

When the organic titanium compound is used, the organic titanium compound may be mixed with the photoconductive material powder into a binder and dispersed. It is preferable that the particles be adsorbed onto the surface of the particles by mixing, and then dispersed in the binder.

In order to obtain excellent image properties and moisture resistance, the organic titanium compound should be added in an amount of 0.0 parts by weight per 100 parts by weight of the photoconductive material.
It is preferable to mix it in a proportion of 1 to 3 parts by weight. If the organic titanium compound is less than o or oi parts by weight, almost no effect can be expected; if it exceeds 3 parts by weight, the photoconductive material powder particles may aggregate, resulting in poor dispersion or photoconductive paint. This is because it increases the viscosity of the product, leading to deterioration of productivity.

Other components of the photoconductive paint include photoconductive material powder,
There are binders and their solvents, but there are no particular restrictions on these, and commonly used ones may be used. For example, photoconductive powders include, but are not limited to, inorganic photoconductive powders such as zinc oxide, cadmium sulfide, organic photoconductive powders such as diazo dyes, and copper phthalocyanine dyes. isn't it. Further, examples of the binder include polystyrene, polyethylene, polypropylene, vinyl resin, acrylic resin, polycarbonate, polyurethane resin, and copolymers of these monomers, but are not limited thereto.

Next, examples of the present invention will be described.

Example 1 173 parts by weight of cadmium carbonate was added to an aqueous solution containing 0.68 parts by weight of cupric chloride, and hydrogen sulfide was blown into the solution.
(Cu)-ncdcO3 precipitated cells. The precipitate was separated, washed with water, dried, crushed, and calcined at 250°C for 15 hours to form CdS(Cu)-ncdcO.
3. Obtain photoconductive powder. 100 parts by weight of this photoconductive powder was added to 170 parts by weight of a toluene solution in which 0.1 part by weight of K R-TTS (trade name of a titanium coupling agent manufactured by Kenrich Petrochemicals) was dissolved, and the mixture was thoroughly stirred. After that, it was dried. 100 parts by weight of Cd5(Cu)/ncdcO3 powder treated with this titanium coupling agent, 60 parts by weight of Acridic A405 (trade name of thermosetting acrylic resin manufactured by Dainippon Ink Co., Ltd.), 2 parts by weight of toluene,
A photoconductive coating material is prepared by thoroughly kneading the mixture with 30 parts by weight in a ball mill to uniformly disperse it. This photoconductive paint is applied onto an aluminum substrate, dried and then thermally cured to form a 30 micron thick photoconductive layer. A solution of the acrylic resin was applied onto this photoconductive layer, and after drying, it was heated at 130°C for 3 hours.
A protective layer having a thickness of 0.5 to 1 μm is formed by heating and curing for 0 minutes to produce an electrophotographic photoreceptor.

Example 2 Cd5(Cu)・nCdC obtained by the same method as Example 1
After mixing 100 parts by weight of O3 powder with 2 parts by weight of KR-3450 in a ball mill for about 5 hours, 60 parts by weight of acrylic resin and 230 parts by weight of toluene were added and thoroughly kneaded to prepare a photoconductive paint. An electrophotographic photoreceptor was prepared in the same manner as in Example 1.

Comparative Example 1 CdS(Cu)-nc obtained in the same manner as Example 1
100 parts by weight of dcO3 powder and Acridic A4056
0 parts by weight and 230 parts by weight of toluene to prepare a photoconductive coating material, and produce an electrophotographic photoreceptor in the same manner as in Example 1.

For each of the photoreceptors prepared in Example 1, Example 2, and Comparative Example 1, the initial electrostatic properties were determined using a commercially available copying machine, and the photoreceptors were left in an atmosphere at a temperature of 25° C. and a relative humidity of 85% for 72 hours. Electrostatic characteristics and image quality after humidity control processing 1. was measured. The results are shown in Table 1. The primary charging voltage applied to the copying machine is -5.5KV, and E200 is the initial charging voltage V.
This is the exposure amount until o drops to 200V.

Table 1 As is clear from the results in Table 1, the electrophotographic photoreceptor of the present invention containing an organic titanium compound has almost the same initial characteristics as that of Comparative Example 1, but after humidity conditioning, While the electrostatic properties are almost the same as the initial properties, Comparative Example 1
Those have deteriorated significantly. Furthermore, while the photoreceptor of the present invention has good image quality after humidity conditioning, the photoreceptor of Comparative Example 1 suffers from image deletion and white spots and is inferior in image quality. For these reasons, according to the present invention, moisture resistance and dispersibility can be improved, and a good dispersion state can always be obtained, so that manufacturing reproducibility can be improved.

Example 3 Using 40 parts by weight of Lionol Blue ER (trade name of steel phthalocyanine pigment manufactured by Toyo Ink Co., Ltd.) as a photoconductive material, this was mixed with 40 parts by weight of a methyl ethyl ketone solution containing 0.04 parts by weight of KR-TTS. After stirring thoroughly, dry the mixture. Next, this is OXL-g
7 (Product name of thermoplastic acrylic resin manufactured by Mitsui Toatsu Co., Ltd.)
A photoconductive paint is prepared by kneading the mixture with 60 parts by weight and 230 parts by weight of ethyl acetate in a ball mill for 30 hours to uniformly disperse the mixture. This photoconductive paint is applied to an aluminum substrate and dried to produce an electrophotographic photoreceptor having a 20 μm thick photoconductive layer.

Comparative Example 2 Lionol Blue ER40 parts by weight were added to 0XL-9760.
and 230 parts by weight of ethyl acetate to prepare a photoconductive paint in the same manner as in Example 3.A photoreceptor for electrophotography was prepared in the same manner as in Example 3 and Comparative Example 2. Regarding the photoreceptor, initial electrostatic properties and 25°C 185%
The electrostatic properties and image quality after being left in an RH atmosphere for 72 hours were measured. The results are shown in Table 2.

As is clear from the results in Table 2, according to the present invention, a photoreceptor with excellent moisture resistance and image characteristics can be obtained even when an organic photoconductive material is used.

Patent applicant: Agent for Minolta Camera Co., Ltd.
Patent attorney Aohaku Ao and 2 others

Claims (2)

[Claims] (1) General formula: % formula %) X4 represents -11, -NH2 still represents -SI (tn
, n are the same or different and are integers of 0 to 3, m −1-n
= satisfies 2 or 3. 1. A photoreceptor for electrophotography, characterized in that a photoconductive paint containing an organic titanium compound represented by the following formula is coated on a substrate to form a photoconductive layer. (2) 0.01 parts by weight of the organic titanium compound is added to 100 parts by weight of the photoconductive material powder contained in the photoconductive paint.
The electrophotographic photoreceptor according to claim 1, which contains .about.3 fold moieties.