JPS60256150A - Phthalocyanine photosensitive body - Google Patents

Abstract

PURPOSE:To enhance resistances to printing and humidity by forming a photoconductive layer prepared by dispersing a phthalocyanine type photoconductor powder coated with a electrostatic charge transfer material and/or an antioxidant or allowed to absorb them into a binder resin. CONSTITUTION:The photoconductive layer is formed by dispersing a phthalocyanine type photoconductor powder coated with the charge transfer material and the antioxidant allowed to absorb them into the binder resin, resulting in remarkably enhancing deterioration preventive effect on such a treated photoconductor. The coating material prepared by mixing such a treated photoconductor with the binder resin has a good viscosity, such as low viscosity and low tendency to structural viscocity, and good storage stability due to no agglomeration tendency. The electrophotographic sensitive body obtained by using it has good electrophotographic characteristics, such as photosensitivity, repetition durability, humidity resistance, and printing resistance.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an electrophotographic photoreceptor, and more particularly, to an electrophotographic photoreceptor having a photosensitive layer formed by dispersing photoconductive material particles in a binder made of an insulating polymeric material as a substrate. The present invention relates to an electrophotographic photoreceptor formed by:

BACKGROUND ART In recent years, for example, 7-talocyanine-based photoconductivity has been disclosed in JP-A-38543, JP-A-51-95852, JP-A-53-64040, JP-A-53-83744, etc. A photoreceptor having a photosensitive layer having a material dispersed in a binder has been proposed.

In this type of electrophotographic photoreceptor, electrons generated inside the photosensitive layer are difficult to be conducted to the surface of the photosensitive layer, and as a result, it takes time for the surface charge to disappear, that is, to form an electrostatic latent image (the so-called ingukushishin effect). There were problems such as gradation, moisture resistance, and performance deterioration due to repeated use (printing durability).

As a method for improving the printing durability of the above-mentioned problems, a method has been proposed in which the surface of a photoconductive organic pigment, such as phthalocyanine, is coated with a suitable resin such as a polypeptide resin (Japanese Unexamined Patent Application Publication No. 1983-1995). -4137 publication). However, coating the shell with a photoconductive organic pigment using lJ4 resin is not always a satisfactory method as it tends to result in a decrease in the sensitivity of the photoreceptor.

OBJECTS OF THE INVENTION It is an object of the present invention to improve the printing durability and moisture resistance of a phthalocyanine photoreceptor without causing a decrease in sensitivity.

Structure of the Invention The present invention provides a phthalocyanine photoreceptor in which a photosensitive layer is formed by dispersing a material powder in a binder (11 resin) to a basic thickness of 1°. Phthalocyanine-based photoconductive material powder or charge transport material and/or
Or, it relates to a phthalocyanine photoreceptor characterized by being coated or adsorbed with an oxidation 11Jj +t: agent.

7 ria cyanine-based photoconductive information used in the present invention (
As the material, any known phthalocyanine and its derivatives can be used, and examples include copper, silver, beryllium, magnesium, calcium, gallium, II
E Lead, cadmium, barium, mercury, aluminum,
Inum, lantern, neonum, samarium, eurobinum, gadolinimum, n°subrosium 11,
Holemium, sodium, lithium-11, interbium, lutetium, titanium, tin, hafneum, lead, trinium, vananoum, antimony, chromium-11, moly7
These include den, uranium, manganese, iron, copper, nickel, iron, palladium, osmium, and platinum. In addition, the central core of the phthalocyanine may not be the metal IQ/-, but may be a handified metal having a valence higher than or equal to j (valency).Furthermore, copper-1-ami7phthalocyanine, iron polyhalophthalocyanine, cobalt Hexaphenyl-7-talocyanine, tetraazo-7-thalocyanine, tetramethyl]talocyanine, alkylamine-7-talocyanine,
Derivatives of metal-free phthalonanine such as f-cyanine can be used. Are these alone or l1jJ? Can be used together.

A phthalocyanine derivative in which the hydrogen atom of the benzene nucleus in the phthalocyanine molecule is substituted with at least one electron-withdrawing group selected from the group consisting of a nitro group, a cyano group, a halogen radical, a sulfone group, and a carboxyl group, and a phthalocyanine and +ijj A phthalocyanine compound obtained by mixing at least one 712-converted 7-thalocyanine compound selected from the anine compounds described in Section 7 with an inorganic acid capable of forming a salt with them and precipitating with water or a base or substance. It is also possible to use a photoconductive material paste. In this case, the electron-withdrawing group-substituted phthalocyanine derivative can be any number of substituents in the molecule, In addition, the electron-withdrawing group substitution 7a
The composition ratio of the cyanine derivative and other unsubstituted phthalocyanine compounds is such that the number of substituents of the former is 7 units in the composition.
It is preferable that the number of molecules per molecule of thalocyanine be 0, (1 (11 to 2), preferably 1 to 0.0+12. Examples of inorganic acids that can form salts with phthalocyanine compounds include sulfuric acid, orthophosphoric acid, chlorosulfonic acid, hydrochloric acid, hydroiodic acid, hydrofluoric acid, and hydrobromic acid.

Among the photoconductive materials, those particularly suitable for achieving the object of the present invention include metal-free phthalocyanine, copper-7 thalocyanine, and derivatives thereof, such as derivatives substituted with attractive groups.

The electrically insulating binder resin used in the present invention may be a thermoplastic material known per se that is electrically insulating. All binders can be used, such as JJ resin, thermosetting resin, photocurable resin, and photoconductive resin.

Examples of suitable binder resins include, but are not limited to, saturated polyester resins, polyamides (3! resins, acrylic IJJ resins, ethylene-vinyl acetate copolymers, ionically crosslinked olefin copolymers (i.e. 7-), styrene-butane block copolymer, polycarbonate, vinyl chloride-vinyl acetate copolymer, cellulose ester,
Thermoplastic binders such as polyimide; thermosetting binders such as epoxy O (fat, urethane resin, silicone resin, 7-el resin, melamine resin, xylene resin, alkyd 0) fat, thermosetting acrylic resin, etc. agent; photocurable resin; poly-N
- Photoconductive resins such as vinylcarbazole, polyvinylpyrene, and polyvinylanthracene.

These electrically insulating resins have a resistance of 1×1014 when measured alone.
It is desirable to have a volume resistivity of Ω·cm or more.

As the conductive support, a foil or plate of copper, aluminum, silver, iron, nickel, etc. in the form of a sheet or drum is used, or these metals are coated with a bra-filled film or the like under vacuum. Plating and electroless plating are used.

As the charge transport material, commonly known compounds such as hydrazone type, oxanoazole type, triphenylmethane type, pyrazoline type, and styryl type can be used. Among these, hydrazone compounds represented by the following general formula III are particularly preferred.

\ In l.

In formula 1, R is hydrogen or a methyl group, 1<, and 1(
, is alkylno, (, aralkyl group or aryl group which may have a substituent, fused polycyclic group which may have a substituent, t\ is an aromatic hydrocarbon group which may have a substituent) , or an aromatic heterocyclic group, 11 represents the number 1 or 2;

R2 and R may both be combined to form a ring. 1 Regarding these compounds, an example is given in JP-A-5-1151.
112b publication, Japanese Patent Application Publication No. 55-46760,
JP-A-55-154955, JP-A-55-520
It is stated in Public Law No. 63, etc.

Furthermore, the charge transport material may be polyvinylcarbazole, polyvinylanthracene, or the like, which are themselves polymers. By coating with a phthalocyanine-based photoconductive material, the sensitivity and repeatability characteristics are improved.
) Ozone resistance, printing durability, and moisture resistance are improved.

In the present invention, the coating or adsorption treatment of the phthalocyanine-based photoconductive material may be performed in place of the charge transporting material, or simultaneously with the coating or adsorption treatment using an antioxidant.

The antioxidant 11-agent is not particularly limited, but a hinged phenol antioxidant is preferred. Irga 7 Nox 1222.565.1 () 35.1 f
l 1 (1,1076, i (l !l 8 (manufactured by Ciba Iggy), Sea7Inx M-2 (10,22 (
1 (manufactured by Shiraishi Calcium Co., Ltd.), Antioxidant N
There are KF (manufactured by Bayer), etc.

When a charge transport material and oxidation protection + I-cutting are used in combination, the effect of preventing deterioration of the conductive material due to osson resistance etc. is clearly enhanced.

In one embodiment of the present invention, the phthalocyanine-based photoconductive material powder and the charge transport material and/or the antioxidant 11
- Prepared by pre-dispersing the shavings and then drying.

In an embodiment of the present invention, a phthalocyanine-based photoconductive material powder is mixed with a charge transport material and/or an antioxidant, and the phthalocyanine-based photoconductive material is It is prepared by fixing a charge transporting material, etc. to

In an embodiment of the pond of the present invention, a phthalocyanine-based photoconductive eyelid powder is surface coated with a charge transport material and/or an antioxidant.

In the case of the present invention, the binder resin is preferably dispersed after the surface is coated with a charge transport material and/or an antioxidant. is adsorbed to the photoconductor material, so it exhibits some effect.

In addition, a method was proposed in Japanese Patent Application No. 1641 GO of 1982, in which a large amount of a hydrazone compound was added to a photosensitive layer made of a phthalocyanine-based photoconductive material (H1 fat) to sensitize it. In addition to coating or adsorbing the charge transport material on the surface, the charge transport material may also be dispersed in the phase, in which case the two may be the same or different.
is desirable.

The photoreceptor of the present invention is prepared by cross-dispersing the photoconductive material whose surface is coated with the charge transport material J5 and/or the antioxidant as described above together with a solvent in a binder O (fat) to prepare a photosensitive coating solution. This is applied directly to the conductive substrate 1- or to an intermediate scrap 1- formed thereon, dried, and further heat-treated to form a photosensitive layer.

The amount of surface coating charge transport material used in the present invention is 0.5-5% by weight, preferably 1-30% by weight, based on the phthalocyanine.

The amount of antioxidant used in the present invention is 0.01 to 30% by weight, preferably () based on the phthalocyanine.

It is 1 to 20% by weight.

When an antioxidant and a charge transport material for surface coating are used in combination, it is appropriate that the total amount of both be in the range of 0.5 to 80% by weight, preferably 1 to 50% by weight, based on 7 talocyanine. .

In a particularly preferred embodiment, the weight ratio of the antioxidant to the charge transport material for surface coating is 9:1 to 2:8, and the total amount of both is 1 to 50% by weight based on phthalocyanine.

Regarding the blending ratio of the phthalocyanine-based photoconductive material and the binder resin, as the amount of the former increases, the sensitivity improves;
On the other hand, as dark decay increases steadily, charge retention becomes poorer and practicality becomes poorer.On the other hand, if the former decreases, dark decay decreases or sensitivity decreases, so the amount of photoconductive material is reduced. Binder O (5 to 100 parts by weight, preferably 10 to 60 parts by weight, based on 1 part by weight of fat 111 f).

Effects of the Invention When the surface-coated photoconductor material of the present invention is made into a paint together with a binder resin, the paint exhibits good fluidity, such as low viscosity and little tendency to exhibit structural viscosity, and is also non-toxic. Because of its cohesive properties, it has excellent storage stability, and the electrophotographic photoreceptor obtained from Kakko's photoconductor material has good electrophotographic properties, such as light sensitivity, repeatability, moisture resistance, and printing durability. Shows excellent properties in terms of gender, etc.

The electrophotographic photoreceptor using the photoconductor material of the present invention can be used not only for electrophotography with only the photosensitive layer according to the present invention, but also for electrophotography in which a barrier layer, an insulating layer, and photosensitive layers of other photoconductor materials are laminated. It may be the body.

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

Example 1 50 parts by weight of ε-type copper 7 talocyanine and 5 parts by weight of N-ethylcarbazole-3-fuldehydonophenylhydrazone were dispersed together with 50 parts by weight of tetrahydrofuran, and then dried to evaporate the tetrahydro 7-ran and dispersed with a hydrazone compound. A surface coated phthalocyanine was obtained.

15 parts by weight of the resulting surface-coated phthalocyanine, thermosetting acrylic resin (Acrydic A 40'): 1
1- (Dainippon Ink Co., Ltd.) 28 parts by weight, melamine resin (Super Beckamine, J820: Dainippon Ink (
a)! ! ! ) 7 parts by weight, 20 parts by weight of p-diethylaminobenzaldehydonophenylhydrazone and methyl isobutyl ketone:cellosolve acetate (1:1)
A photoconductive paint is prepared by kneading a mixed solvent (which does not dissolve the coating layer (hydrazone) much) using a ball mill for 48 hours, and this paint is coated on an aluminum substrate with a coating of about 1
A photoreceptor was prepared by applying the coating to a thickness of 5 μm.

Throne box: 50 parts by weight of λ-ε type copper 7 talocyanine, 10 parts by weight of p-cybenyl aminobenzaldehyde methylphenylhydrazone, and 0.5 parts by weight of an antioxidant (Irganox 10F G: manufactured by Ciba Geigy) were added to 50 parts by weight of tetrahydrofuran. After dispersing the mixture in 1 part, it was dried and the tetrahydrofuran was evaporated to obtain a phthalocyanine whose surface was coated with a hydrazone compound.

The resulting surface coating 7 contained 15 parts by weight of talocyanine, 28 parts by weight of thermosetting acrylic resin (Acrizo Ink A405:12-manufactured by Dainippon Ink Co., Ltd.), melamine O (fat
Super Beckamin J820: Manufactured by Dainippon Ink Co., Ltd.)
Using a ball mill, 7 parts by weight, 20 parts by weight of p-noethylaminobenzaldehyde diphenylhydrazone, and a mixed solvent of methyl isobutyl ketone: cellosolve acetate (1:1) (which does not dissolve the coating layer very much) were mixed with 48 parts by weight using a ball mill.
A photoconductive paint was prepared by kneading for a period of time, and this paint was applied to an aluminum substrate-1 to a thickness of about 15 μr11 to prepare a photoreceptor.

Example 3 50 parts by weight of ε-type copper phthalocyanine and 10 parts by weight of p-noethylaminobenzaldehyde diphenylhydrazone were dispersed in 40 parts by weight of methyl ethyl ketone, and then dried to evaporate the methyl ethyl ketone to obtain 7 talocyanine whose surface was coated with a hydrazone compound. I got it.

15 parts by weight of the obtained surface-coated phthalocyanine, thermosetting acrylic resin (HR620: manufactured by Mitsubishi Rayon Co., Ltd.) 2
8 parts by weight, melamine O (fat (Kneepan 20118:,:
, Seitoatsu Co., Ltd. M) 7 parts, I]-noethylamide 7 benzaldehydonophenylhydrazone 20 parts and methyl isophthyl ketone: cellosol 7 acetate) (1:
A photoconductive paint was prepared by kneading the mixed solvent of 1) for 48 hours using a ball mill. This paint was applied to an aluminum substrate 1- to a thickness of about 15 μm to produce a photoreceptor.

! Clam Example-1 An electrophotographic photoreceptor was prepared in exactly the same manner as in Example 1 except that the ε-type copper 7 talocyanine particles were used as a charge transport material and no cordon was used.

! f1! Comparative example? - 50 parts by weight of ε-type copper phthalocyanine, polycarbonate) 1
(Panrai KI311n: Yojin Kasei Co., Ltd.) 5 parts by weight of 1.2-N chloroethane 5 (11 parts by weight) were dispersed in 31 parts of 1.2-N chloroethane (5 parts by weight).Next, 100 parts by weight of 1.2-N chloroethane was added to dilute, and the mixture was stirred. After gradually adding n-hexane from the mixture, the precipitated fine particles were filtered, separated, and dried to obtain phthalocyanine whose surface was coated with polycarbonate.

15 parts by weight of the obtained surface-coating phthalocyanine, 28 parts by weight of thermosetting acrylic resin (Acrizo Ink A 4 (+5: manufactured by Dainippon Ink Co., Ltd.), melamine resin (Super Bencamine J 820: Dainippon Ink (+2)) A mixed solvent of 7 parts by weight, 20 parts by weight of diethylamide 7-benzaldehydonophenylhydrazone, and methyl isobutyl ketone (cellosolve acetate) (]:1) was kneaded for 48 hours using a ball mill to form a photoconductive paint. One coat of this paint was applied onto an aluminum substrate to a thickness of about 15 μm to produce a photoreceptor.

50 parts by weight of copper phthalocyanine and 2 parts by weight of tetranitro copper phthalocyanine were dissolved in 300 parts by weight of 98% concentrated sulfuric acid with thorough stirring. The dissolved solution is poured into 3000 parts by weight of water to precipitate a composition of copper phthalocyanine/tetranitrocopper phthalocyanine. Thereafter, it is filtered, washed with water, and dried at 420°C under reduced pressure.

Next, to 10 parts by weight of this composition, 1 part by weight of N-ethylcal 15-babou-3-aldehyde benzyl phenyl 19 fufu and 10 parts by weight of tetrahydro 7ran were added, and after dispersion, it was dried to obtain tetrahydro 7ran. After evaporation, 7-talocyanine surface-coated with hydrazone compound was obtained.

10 parts by weight of the obtained surface-coated phthalocyanine, thermosetting acrylic O (fat (HR620: manufactured by Mitsubishi Rayon (a))
28 parts by weight, melamine O (fat (Kneepan 2011S: manufactured by Mitsui Toatsu Co., Ltd.) 7 parts by weight, 20 parts by weight of p-diethylamide 7-benzaldehydonophenylhydrazone and methyl isobutyl ketone: cellosolve acetate) (1:1)
A photoconductive paint was prepared by kneading the mixed solvent for 48 hours using a ball mill, and this paint was coated on an aluminum substrate to a thickness of about 15 μm to prepare a photoreceptor.

Fire Salmon Σ 50 parts by weight of the copper phthalocyanine/tetranitro copper phthalocyanine composition obtained in Example 4 and 8 parts by weight of bis(2-methyl-4-diethylamino-7enyl)-cyclohexylmethane were added to 50 parts by weight of tetrahy-16-dorofuran. After dispersing in parts by weight, it was dried to obtain 7talonanine whose surface was coated with the nphenylmethane compound.

The obtained surface-coated phthalocyanine 10'fLfiB, thermosetting acrylic O (fat (HR62 (1: Mitsubishi Rayon)
KK)! ! 28 parts by weight, melamine resin (Kneepan 201
-IS: 7 parts by weight (manufactured by Mitsui Toatsu Co., Ltd.), 20 parts by weight of p-noethylaminobenzaldehydonophenylhydrazone, and cellosolve acetate (which does not dissolve the coating layer) were added and kneaded for 48 hours using a ball mill. hand,
A photoconductive paint was prepared. This paint was applied onto an aluminum substrate to a thickness of approximately 15 μIO to produce a photoreceptor.

Rescuer 1 An electrophotographic photoreceptor was produced in exactly the same manner as in Example 4, except that the phthalocyanine particles were not footed with a charge transport material.

Comparative Example 4 The experiment was carried out except that the phthalocyanine particles were not footed with a charge transport material and N-ethylcarbazole-3-aldehyde♂bennorphenylhydrazone was used instead of p-noethylaminobenzaldehydonophenylhydrazone. In exactly the same manner as in Example 4, an electric f'';intuition'L tree was created.

Example 6 Example except that antioxidant 11'-n'l (Irganox 1 (Bi16: Chiha Igine I'A/) was used in place of N-ethylcarbazole-;3-aldehydebennorphenylhydrazone) A photoreceptor was prepared in exactly the same manner as in step 4.

(Transfer a commercially available powder image to a 11-electrophotographic photoreceptor (manufactured by Minolta Camera Co., Ltd.; l:!' = 1)
5 o 7. ), and a +6.5KV corona discharge is applied to the photoreceptor surface immediately after applying it to the photoreceptor surface type),
〉\lo(~'), surface potential extinction rate D1) after being left in ni for Il+, R, (X), and Table 1 after exposure
The exposure power required to reduce the hi electric potential to 1/2 of the initial surface potential is 1. The surface potential when the repeated operations of -exposure and static elimination were repeated) and the sensitivity 1: + and y2 were measured.&ll+AL: are shown in Table 1.

19- As is clear from the results in Table 1, the photoreceptor of the present invention has a low sensitivity of 1.0%, and the results of repetitive characteristics - ζ and other comparative examples have a high sensitivity. It was a phthalocyanine-sensitized product that showed excellent properties compared to the standard Iso and laser printers.

] 20-

Claims (1)

[Claims] 1.7 In a phthalocyanine photoreceptor having a photoconductive layer formed by dispersing thalocyanine-based photoconductive material powder in a binder resin, the phthalocyanine-based photoconductive material powder is a charge transport material and/or an antioxidant. A phthalocyanine photoreceptor characterized by being coated or adsorbed.