JPS604458B2 - photoconductive composition - Google Patents

Description

[Detailed description of the invention] FIELD OF THE INVENTION This invention relates to photoconductive compositions.

More specifically, the present invention aims to provide a photoconductive composition that can be used as an electrophotographic light-sensitive material that has both film-forming ability and photosensitivity. Photoconductive substances used in known electrophotographic photosensitive materials include selenium,
Inorganic substances such as zinc oxide and cadmium sulfide, or anthracene, carbazole, anthraquinone, berylene, etc.
or a series of heterocyclic compounds, and organic materials such as polyvinylcarbazole polymers and the like.

Xerox, Electrofax, etc. are known as those using inorganic substances. On the other hand, even if organic substances such as anthracene, carbazole, anthraquinone, and berylene are used, these are crystalline low-molecular compounds and do not have a film-forming structure.
They are characterized by a transparent photosensitive layer and high sensitivity, but since they are all low-molecular compounds and do not have the ability to form a film on their own, they add about 50% synthetic resin as a binder to create a photoconductive layer. It is used in the form of Oka solution with substances. Furthermore, since photosensitive materials using polypynylcarbazole are extremely brittle and have a weak film-forming ability, they still require a binder. As a result of extensive research into electrophotographic light-sensitive materials that themselves have both sufficient film-forming ability and photosensitivity, the present inventors discovered that aromatic condensed polycyclic compounds consisting of three or more rings and/or their We have discovered that a composition obtained by mixing a resin obtained by co-condensing a nuclear substituted product with an alkylbenzene aldehyde resin and [B' poly(alkylene naphthalene dicarboxylate)] has such characteristics, and the present invention invention has been achieved.

That is, the present invention provides an aromatic condensed polycyclic compound consisting of three or more rings and/or
Alternatively, a resin obtained by co-condensing its nuclear substituted product with an alkylbenzene aldehyde resin and a poly(alkylene naphthalene dicarboxylate) whose main glycol component is a glycol having 2 to 6 carbon atoms. It is a photoconductive composition formed by mixing.

The alkylbenzene/aldehyde resin used as component (2) in the present invention is a resin obtained by condensing an alkylbenzene and an aldehyde.

The alkylbenzene used to obtain the resin may be any benzene having 1 to 4 substituted alkyl groups, and examples thereof include toluene, xylene, ethylbenzene, jetylbenzene, etc., but especially m -Dialkylbenzenes (eg m-xylene) are preferred. As the aldehyde, an aliphatic aldehyde having 6 or less carbon atoms (typical examples include formaldehyde, acetaldehyde, furfural, etc.) is preferably used, and formaldehyde is particularly preferably used. Therefore, the most preferred resin is m-xylene formaldehyde resin.
The aromatic condensed polycyclic compound used in the present invention has a condensed ring consisting of three or more rings.

Basic examples of such compounds (those having no nuclear substituents) include anthracene, phenanthracene, pennzanthracene, pyrene, chrysene, tetraphenone, tetracene, berylene, 1,2,5,6-dibenzanthracene, etc. Illustrated. Typical nuclear substituents of such compounds include alkyl groups, amino groups, nitro groups,
Examples include a halogen atom, an aminoalkyl group, a phenyl group, a diazophenyl group, an aminoalkylphenyl group, an aminophenyl group, an aryl ether group, and a chlorosulfone group. The aromatic condensed polycyclic compound used in the method of the present invention preferably has no nuclear substituents and/or has 1 to 3 nuclear substituents. The aromatic condensed polycyclic compound may be used alone or in combination of two or more. The blending ratio of the alkylbenzene aldehyde resin and the aromatic condensed polycyclic compound is
Too little of the latter tends to reduce the sensitivity of the resin, while too much of the latter tends to make the resin brittle. Therefore, in order to achieve both appropriate sensitivity and excellent film-forming ability, the latter is usually increased in weight ratio. The ratio of the former to the former is preferably 0.2 to 1.9, preferably 0.4 to 1.0.

However, depending on the purpose, it may be blended in a ratio outside this range. The alkylbenzene aldehyde resin used is one that can still be melted, and is subjected to a co-condensation reaction with the aromatic condensed polycyclic compound.

The reaction temperature is preferably 100 to 300 oo, and the reaction time is preferably 10 minutes to 10 hours. The reaction is preferably carried out under an inert gas atmosphere or under reduced pressure. In the poly(alkylene naphthalenedicarboxylate) used as a music component in the present invention, 85 mol% or more, preferably 90 mol% or more of the dicarboxylic component is occupied by naphthalene dicarboxylic acid, and the diol component is occupied by naphthalene dicarboxylic acid. The polyester is such that 85 mol% or more, preferably 90 mol% or more is occupied by alkylene glycol.

Naphthalene dicarboxylic acid can be used in any one of its 10 isomers, including naphthalene-2,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, naphthalene-1,5-dicarboxylic acid, naphthalene-1,4-dicarboxylic acid, and naphthalene-1,4-dicarboxylic acid. Acids, particularly naphthalene-2,6-dicarboxylic acid, are preferably used. Also, alkylene glycol has 2 carbon atoms.
Although any one of 6 to 6 can be used, linear alkylene glycol (e.g., ethylene glycol, trimethylene glycol, tetramethylene glycol, hexamethylene glycol, etc., especially ethylene glycol is preferably used. For example, dicarboxylic acid and diol may be directly polymerized, dicarboxylic acid ester and diol may be transesterified and then polymerized, di(hydroxyalkyl dicarboxylic acid) ) The ester may be polymerized by deglycol reaction.These polyesters may be homopolymers, copolymers, or a mixture of two or more types of polyesters.The above components and In order to mix component 'B}, both may be mixed in a molten state, or both may be dissolved and mixed in a common solvent.

The mixing ratio of the wind component and the 'B-component is preferably 2/1 to 1/100 in weight ratio of W/BI. The photoconductive composition thus obtained has both film formation and photosensitivity (photoconductivity), and can be used as a photosensitive material for electrophotography as it is or with a sensitizer or enhancer as necessary. It is used in the form of a film by adding sensitizers, plasticizers, etc.

As the sensitizer, dyes and strong electron acceptors are preferably used.

By adding a dye, the photosensitive region of the photoconductive composition moves to the light absorption region of the dye, that is, the visible region, and the composition exhibits sufficient sensitivity even in the visible region. Examples of such dyes include brilliant, green, methyl violet, crystal violet, rhodamine B, rhodamine B extra, rhodamine 80, sulfurhodamine B, rose bengal, methylene blue, and alizarin. A preferable addition ratio of the sensitizer to the photoconductive composition is 0.01 to 3. is the weight% of
It is not necessarily necessary to add it. As the sensitizing aid, aromatic quinones, aromatic halides, acid anhydrides, cyano compounds, and aromatic nitro compounds are preferably used.

These form charge-transfer type complexes with the photoconductive composition and increase photoconductivity. Preferably used compounds include aromatic quinones such as p-benzoquinone, 1,2-penzanthraquinone, anthraquinone, naphthoquinone, 2-methylanthraquinone, 2-chloroanthraquinone, etc., aromatic halogen compounds such as bromal, chloral, trichlorobenzene, etc. Acid anhydrides such as maleic anhydride, phthalic anhydride, succinic anhydride, etc., cyano compounds such as tetracyanoethylene, tetracyanoquinodimethane, etc., aromatics such as trinitrofluorenone, tetranitrofluorenone, bentanitrofluorenone, etc. Examples include nitro compounds. A preferable addition ratio of the sensitizing agent is 0.1 to 50% relative to the photoconductive composition.
% by weight, particularly preferably from 1 to 15% by weight, but it is not necessary to add it. The plasticizers include p-terphenyl, diphenyl, diphenyl ether, diphenyl chloride, methylnaphthalene, dioctyl phthalate,
Examples include triphenyl phosphoric acid, dimethyl glycol phthalate, and dibutyl phthalate.

The addition of plasticizers improves the properties of the coating. The addition ratio of the plasticizer is preferably 1 to 4% by weight based on the photoconductive composition, but it is not always necessary to add the plasticizer. In order to form the photoconductive composition into a film, the composition can be melt-extruded or made into a solution and cast to form a film, or the solution can be coated on a suitable support and dried. Just use a membrane. The formed film may be used for electrophotography by being attached to another substrate. To make the photoconductive composition into a solution, o-chlorophenol is used as a solvent.
m-cresol and the like are preferably used. A known method may be used to apply the solution containing the photoconductive composition to the support.

For example, a method of casting the solution, a spin coating method, a spray coating method, a brush coating method, etc. may be used. The thickness of the film is usually 2~
30〃 is preferable. The support may be any material as long as it can be used as a support for the photosensitive layer for electrophotography, such as a metal plate made of aluminum, zinc, copper, etc., or a surface treated with synthetic resin to prevent solvent from penetrating inside. Materials whose surface resistivity is 4 mm higher than the photoconductivity standard, such as synthetic resin films mixed with or coated with antistatic agents or surfactants to lower their electrical resistivity, that is, normal , the resistance is 10
Anything less than 70 skins, preferably 1 pi** fox or less is acceptable. Any conventionally known method may be used to obtain an electrophotographic image, and the charged potential may be either positive or negative.

The photoconductive composition of the present invention has excellent sensitivity as a photosensitive material for electrophotography, and can form a film having excellent maneuverability and mechanical properties.

Therefore, a photosensitive sheet made by coating this on a transparent film is
It is used for masters and duplicates of slides, micro-photographs, overhead projectors, etc., and when coated and baked on a metal cylinder, it is used as a transfer tube for xerography. Furthermore, the paper coated with it is more similar to plain vapor than the conventional zinc oxide coated paper, and it is possible to obtain copies that are similar to plain vapor and copies. Hereinafter, the present invention will be explained in detail with reference to Examples.

Examples 1 to 4 Xylene, formaldehyde resin (trade name Nicanol S
Using IO0 (Mitsubishi Gas Chemical K.K. product)) 9.6 pieces, add 5.5 hours of anthracene, and boil for 16 minutes under a nitrogen stream.
The reaction was carried out at a temperature of 0 to 19 pi for 4 hours, and the reactant was dissolved in toluene and reprecipitated using methanol to obtain a condensate.

This was used as the poisonous ingredient. In addition, {8) as a component,
Polyethylene-2,6-naphthalene dicarboxylate having a polyethylene content of 0.894 was used. Both were dissolved in o-chlorophenol in the proportions shown in Table 1, and a solution obtained was cast onto an aluminum plate and dried to form a photoconductive layer with a thickness of 101 mm.

This layer was negatively charged by corona discharge. This was placed under the original and exposed for 5 seconds from a distance of 20 skin using a 300W incandescent light bulb as a light source, then sprinkled with developing powder and heated to fix it, resulting in an image faithful to the original. In addition, half-decreased exposure was measured using a Surf-S Potential Meter SS Low 30 (Kawaguchi Electric K.K. product) and a photocell illuminance meter SPI-1 (Toshiba Electric K.K. product), and the results are shown in Table 1. was gotten.

Comparative Examples 1 to 4 46 mol% of terephthalic acid instead of polyethylene-2.6 naphthalene dicarboxylate as component B
In the same manner as in Examples 1 to 4, except for using a polyester obtained by polycondensing a dicarboxylic brewing component consisting of 54 mol% of isophthalic acid with a diol component consisting of 45 mol% of ethylene glycol and 55 mol% of neobentyl glycol, A photoconductive layer was formed and the half-life exposure was measured.

The results are shown in Table 1. From the results in Table 1 and above, it can be seen that the sensitivity of the comparative examples other than Comparative Example 3 is significantly inferior, and that although the sensitivity of Comparative Example 3 is relatively high (still inferior to the present invention), the film is brittle.

Examples 5, 6 [As the 81 component, poly(ethylene naphthalene-1.
5-dicarboxylate) ([ri]: 0.76) [Example 5], or poly(hexamethylene naphthalene-2)
・6-dicarboxylate) ([ri] = 0.815) [
A photoconductive layer was formed under the same conditions as in Example 2 except that Example 6] was used, and a toner image was formed by charging exposure and development, and a good image was obtained.

Moreover, the photoconductive layer film had good maneuverability.

Comparative Example 5 Polyvinylcarbazole was pulverized, poured into methylene chloride, and reprecipitated using purified methanol, which was repeated three times for purification.

Claims (1)

[Claims] 1 (A) A resin that can be obtained by co-condensing an aromatic condensed polycyclic compound consisting of three or more rings and/or its nuclear substituted product with an alkylbenzene aldehyde resin;
B) A photoconductive composition prepared by mixing poly(alkylene naphthalene dicarboxylate) containing a glycol having 2 to 6 carbon atoms as the main glycol component.