JPH0261737B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a printing plate for electrostatic printing suitable for obtaining small batches of prints of about 100 to 1,000 copies, in which a specific phthalocyanine mixture and zinc oxide are mixed in a binder resin. The present invention relates to a printing plate for electrostatic printing that is manufactured using a photoreceptor that has sufficient sensitivity to semiconductor laser light dispersed in the semiconductor laser beam to an unprecedented degree. That is, one of the objects of the present invention is to create a printing plate for electrostatic printing by writing information input by an electric signal using a semiconductor laser beam, and to print approximately 100 to 1000 copies using the electrostatic printing method. An object of the present invention is to provide a printing plate for electrostatic printing that allows high-quality reproduction to be easily achieved. Recently, with the streamlining of office work, Japanese word processors have become popular. With a conventional typewriter, each character is printed one by one, but with a word processor, the typed characters are not printed out immediately, but are recorded in an electrical storage device (memory). Since it is only displayed on a cathode ray tube, corrections and additions can be made easily. Japanese word processors use inkjet printing, heat-sensitive printing, wire dot printing, and electrophotographic printing using lasers. Among electrophotographic methods using lasers, those using semiconductor lasers are becoming popular. Semiconductor lasers have a relatively small optical output of several mW to several tens of mW during continuous operation, but compared to other solid-state lasers and gas lasers, they are ultra-small, have high efficiency, low voltage, and low power consumption. by current
This is because it has many advantages, including high-speed direct modulation exceeding 1 GHz, good compatibility with peripheral semiconductor circuits such as ICs, high reliability inherent to semiconductors, and the promise of cost reduction through mass production. Therefore, AlGaAs is currently used as a semiconductor laser.
Lasers (visible light and short wavelength lasers) and
InGaAsP lasers (long wavelength lasers) have been put into practical use, but for optical information processing, AlGaAs lasers are used, and visible light lasers with a wavelength of 0.76 to 0.8 μm are used.
Either a short wavelength laser of 0.83 to 0.88 μm is used. However, in laser printers that use semiconductor lasers, the output of the semiconductor laser is small compared to other gas lasers (Ar, He-Ne, He-Cd, etc.).
The copy speed cannot be increased because the sensitivity of currently used photoreceptors is lower than that of semiconductor lasers. The present invention aims to eliminate the above-mentioned drawbacks, and particularly relates to improvements in the photoreceptor used. That is, the present invention writes information directly onto a photoreceptor using semiconductor laser light,
The photoreceptor is used as an electrostatic printing plate to perform high-speed electrostatic printing and meet the needs for large-scale duplication. At present, as conventional optical semiconductors sensitive to semiconductor laser light, CdS-Cu,
There are Se-Te/Se, amorphous Si, phthalocyanine photoreceptors, etc., but considering that they are disposable as electrostatic printing plates, they are unsuitable from the viewpoint of toxicity and material cost. Therefore, as a photoreceptor suitable for use in the present invention, a phthalocyanine photoreceptor is preferred, but the phthalocyanine pigment has an average particle size of 0.05 μm.
Because phthalocyanine is small in size and has poor charge retention properties, the ratio of binder resin components must be increased in order to use it as a photoreceptor, and when a photoreceptor is made from phthalocyanine alone, the surface of the photoreceptor layer is extremely smooth. Therefore, the fixing properties of the toner are extremely poor, and if an image is formed on this photoreceptor with conductive toner and fixed, the toner will peel off during the electrostatic printing process and cannot be used as an electrostatic printing plate. It had some drawbacks. Therefore, the inventors of the present invention conducted extensive research in order to improve the fixation of toner onto the photoreceptor, and as a result, they discovered that the improvement could be achieved by making the surface of the photoreceptor matte. Therefore, various fillers are applied to phthalocyanine pigment-resin photoreceptors.
to test the toner's fixation. When we tested fillers such as titanium oxide, calcium carbonate, cadmium carbonate, magnesium oxide, and zinc oxide, we found that the fixing properties were improved compared to phthalocyanine pigment-resin photoreceptors, but the photosensitivity was significantly lower.
It was confirmed that this resulted in a decrease in charge retention and an increase in dark decay. However, in the case where zinc oxide was selected as the filler, although there was a slight decrease in photosensitivity, the charge retention and dark decay characteristics did not become so bad. In addition, the average particle size of zinc oxide is 0.3μ, which is an order of magnitude larger than that of phthalocyanine pigments, and because it has excellent charge retention, the ratio of binder resin components can be lower than when using phthalocyanine pigments alone. , the surface becomes matte. The matte surface has an increased surface area, which improves toner adhesion. Next, the inventors aimed to improve photosensitivity. Then, the present invention was completed by improving the phthalocyanine pigment that is sensitive to semiconductor laser light as a photoreceptor to a highly sensitive one, and adding zinc oxide as a filler. That is, as a photoreceptor, acid pasting treatment of ε-type copper phthalocyanine (A), phthalocyanine having an electron-withdrawing group, or a mixture of phthalocyanine having an electron-withdrawing group and other phthalocyanines is applied to a conductive support. Phthalocyanine derivative (B)
The photoconductive layer is provided with a photoconductive layer in which a mixture of zinc oxide and zinc oxide are dispersed in a binder resin. The present invention relates to a printing plate for electrostatic printing in which the photoreceptor is charged, exposed to semiconductor laser light or the like to form a latent image, and the latent image is developed and fixed using conductive toner. Hereinafter, the present invention will be explained in detail with reference to the drawings.
As shown in FIG. 1, ε-type copper phthalocyanine (A) and phthalocyanine derivative (B) are
A photoreceptor 3 comprising a photoconductive layer 2 in which a mixture of zinc oxide and a mixture of An electrostatic latent image is formed by exposure with modulated semiconductor laser light 4, and reverse development is performed with conductive toner 5 as shown in FIG. 3, or normal development is performed as shown in FIG. As shown in FIG. 5 or 6, it is fixed, and an electrostatic printing plate 8 consisting of a conductive portion 6 and an insulating portion 7 is produced. In the present invention, as the ε-type copper phthalocyanine (A), X
When measuring the line diffraction angle, we found the strongest line corresponding to the interplanar spacing of 9.72 Å, a strong line at 11.63 Å, 6.24, 5.10, 4.35, 4.19,
Weak lines are shown at 3.87, 3.36, 3.28, and 3.03 Å. It is known from Japanese Patent Publication No. 52-1667 that this ε-type copper phthalocyanine (A) exhibits excellent effects as a photoconductor element for electrophotographic plates. The present invention is characterized by using a photoreceptor prepared by mixing the ε-type copper phthalocyanine (A) with a phthalocyanine derivative (B) and further adding zinc oxide, and which is acid-pasted. Due to the presence of the phthalocyanine derivative (B) having an electron-withdrawing group such as a nitro group, which is a fine particle, it was possible to further improve electrophotographic properties such as photosensitivity. Here, the phthalocyanine having an electron-withdrawing group includes a nitro group, a cyano group,
It is substituted with an electron-withdrawing group such as a halogen atom, a sulfone group, a carboxyl group, a sulfamide group, or a carboxamide group. This phthalocyanine derivative can be obtained by using phthalonitrile, phthalic acid, phthalic anhydride, or phthalimide substituted with the above-mentioned substituents as the raw material for phthalocyanine during phthalocyanine synthesis; It can be obtained by using both. The method for producing the phthalocyanine derivative is not particularly limited.
Further, the number of substituents in one molecule of the phthalocyanine derivative is 1 to 16. The above phthalocyanine having an electron-withdrawing group is
If necessary, acid pasting treatment is performed with other phthalocyanine having no electron-withdrawing group,
A phthalocyanine derivative (B) is obtained. Here, acid pasting treatment refers to the above-mentioned phthalocyanine or phthalocyanine having an electron-withdrawing group being treated with sulfuric acid, orthosulfuric acid, pyrophosphoric acid, chlorosulfonic acid, hydrochloric acid, hydroiodic acid, hydrofluoric acid, or hydrobromic acid. This is a treatment method in which a salt is formed with an inorganic acid such as, and the phthalocyanine derivative is poured into water as known in the organic pigment industry, and the precipitated phthalocyanine derivative is filtered, washed with water, and dried. It will be done. The mixing weight ratio of the ε-type copper phthalocyanine (A) and the phthalocyanine derivative (B) is about 100/0.01 to 100, preferably 100/0.1 to 60, and the electron-withdrawing group is The number of
0.001 or more, preferably 0.01 or more, and 2
It is best to mix so that the number of The photoreceptor used in this application is produced by ball milling the above phthalocyanine mixture together with a binder resin, a solvent, etc.
Uniformly disperse with a kneading dispersion machine such as an attritor,
Furthermore, zinc oxide powder is added, uniformly dispersed using a similar kneading and dispersing machine, and coated onto a conductive support to form a photoconductive layer. Note that it is also effective to provide a barrier layer between the conductive support and the photoconductive layer. Further, as the filler, any zinc oxide that is generally used in powder form for electrophotography can be used. The mixing ratio of the phthalocyanine mixture and zinc oxide is phthalocyanine mixture/zinc oxide = 20~
Good results were obtained at 60 wt%. That is, when the phthalocyanine mixture is less than 20wt%, the photosensitivity to semiconductor laser light is insufficient, while when the phthalocyanine mixture is 60wt%
This is because, if it exceeds this, the fixing properties of the conductive toner will deteriorate. Of course, the above matters are also greatly influenced by the amount of binder resin added. The binder resin ratio was good when the phthalocyanine mixture/binder resin was 25 to 50 wt% from the viewpoint of film properties and charge retention properties. Examples of binder resins include melamine resins, epoxy resins, silicone resins, polyurethane resins, polyester resins, acrylic resins, xylene resins, vinyl chloride-vinyl acetate copolymer resins, polycarbonate resins, and cellulose derivatives with a volume resistivity of 10. ^7Ω
A known material having an insulation property of cm or more is used. In addition, as a solvent, benzene, toluene,
Aromatic hydrocarbons such as xylene and chlorobenzene, ketones such as acetone, methyl ethyl ketone, and cyclohexanone, methanol, ethanol,
Alcohols such as isopropanol, esters such as ethyl acetate and methyl cellosolve, halogenated hydrocarbons such as carbon tetrachloride, chloroform and dichloromethane, ethers such as tetrahydrofuran and dioxane, and dimethylformamide and dimethyl sulfoxide are used. As a conductive support, a metal plate or sheet such as aluminum, brass, copper, or stainless steel, aluminum on a plastic sheet,
Examples of materials that can be used include vacuum-deposited materials such as palladium or metal oxides, plastic plates, conductive treated paper, and metal oxide plates. As for the coating method, if necessary, a solvent is added to adjust the viscosity, and a coating is formed using an air knife coater, blade coater, rod coater, reverse roll coater, spray coater, hot coater, or sweep coater.
After application, drying is carried out using a suitable drying device. In addition, there are two types of conductive toner: liquid toner and powder toner.
A conductive liquid toner is a conductive toner dispersed in an electrically insulating carrier liquid having a boiling point of 100 to 200°C. The toner is composed of a conductive agent, a fixing agent, a charge control agent, and the like. Isoparaffinic solvents with a boiling point of 120 to 200°C are often used as carrier liquids for conductive liquid toners. For positively charging conductive liquid toner, conductive carbon black or the like can be used as the conductive agent, but carbon black treated with nigrosine dye is also used to stabilize the charging polarity. Fixing agents include alkyd resins, cyclized rubbers, natural resins soluble in aliphatic hydrocarbons, asphalt, acrylic resins, copolymers of higher alkyl esters of methacrylic acid and various vinyl monomers, and charge control agents. are fatty acids and metal salts such as naphthenic acid, higher fatty acids,
Antioxidants are used. Examples of the conductive agent for the negatively charged conductive liquid toner include furnace carbon black and grafted carbon black containing vinyl pyrrolidone. Fixing agents include cyclized rubber, acrylic resins, and acrylic resins copolymerized with monomers having highly electronegative phenolic hydroxyl groups, sulfone groups, and ester sulfate groups.Charge control agents include lecithin and oil-soluble sulfonate salts. etc. are used. Powdered conductive toners include conductive powders such as copper, iron, aluminum, silver, zinc, black iron oxide, copper oxide, copper iodide, copper chloride, silver oxide, cobalt oxide, indium oxide, and carbon black. One-component conductive toners may be made of suitable resins that exhibit adhesive properties under the application of heat or pressure, such as styrene resins, epoxy resins, vinyl chloride resins, vinyl butyral resins, acrylic resins, and waxes. generally well known. One-component conductive toners include conductive non-magnetic toners and conductive magnetic toners. As a developing method for conductive non-magnetic toner, there is a touch-down developing method proposed in Japanese Patent Publication No. 37-491 and Japanese Patent Publication No. 37-492. This is a method in which developer particles are uniformly coated and the sleeve is brought into contact with an electrostatic charge image for development.
It is said that the toner preferably has a particle size of 20 μm or less and is made of powdered metal, graphite, carbon black, and thermoplastic resin. Furthermore, as a developing method using conductive magnetic toner, there is a magneto-dry developing method proposed in JP-A-49-4532, in which conductive magnetic toner is magnetically transferred to a magnetic sleeve having a grounded conductive surface. uniformly coat the area,
This is a method of developing an electrostatically charged image by bringing it into contact with a conductive magnetic toner. The toner is composed of a thermoplastic resin, a magnetic material, and conductive fine particles, and the particle size is 1 to 50 μm, preferably 5 to 30 μm, and the conductivity is 10 ⁸
Ωcm to 10 ² Ωcm is good. In addition, when using a one-component conductive magnetic toner, such as one consisting of paraffin wax, ethylene-vinyl acetate copolymer, and black iron oxide (magnetite), steel polishing is generally performed at a pressure of 20 to 30 kg/cm. Pressure fixing is possible through the rolls. Further, for example, a double wall in which the inner wall is made of a colloidal material and the outer wall is made of a mixed system of a hydrophobic resin and a pigment or dye contains a magnetic liquid or semi-solid inside, and the outer wall has a volume of 10 ¹⁰ Ω・cm or less. Conductive magnetic microcapsule toners with resistivity can also be used. Above, we have mainly discussed the use of semiconductor laser light as an exposure method for the photoreceptor, but the photoreceptor used in the present invention has a far greater photosensitivity to semiconductor laser light than conventional products. Although its greatest feature is that it is highly sensitive, it also has excellent photosensitivity to visible light of 400 to 700 nm, and can be sufficiently applied to conventional general exposure methods and light sources. The present invention will be explained below by giving examples. In the examples, "parts" indicate parts by weight. (Preliminary experiment) 40 parts of copper phthalocyanine and 0.5 parts of tetranitrocopper phthalocyanine were dissolved in 500 parts of 98% concentrated sulfuric acid with thorough stirring. Pour the dissolved solution into 5000 parts of water to precipitate a composition of copper phthalocyanine and tetranitrocopper phthalocyanine, wash with water, and heat at 120°C under reduced pressure.
It was dried. 100 parts of the thus obtained composition [] was mixed with 100 parts of ε-type copper phthalocyanine (Lionol Blue ER) manufactured by Toyo Ink Manufacturing Co., Ltd., and dispersed in 5000 parts of methanol to form a uniform mixed dispersion. Thereafter, it was filtered and dried at 120°C under reduced pressure to obtain a mixture []. Next, 5 parts of the above mixture [] and acrylic polyol (Takerakku UA-702 manufactured by Takeda Pharmaceutical Co., Ltd.)
After kneading 25 parts of epoxy resin (Epicoat #1007 manufactured by Ciel Chemical Co., Ltd.), 26 parts of methyl ethyl ketone, and 26 parts of Cellusolve Acetate in a porcelain ball mill for 48 hours, the mixture was mixed with zinc oxide manufactured by Sakai Chemical Co., Ltd.
Add 16 parts of SAZEX2000 and knead it in a porcelain ball mill for another 10 hours, then apply the coating solution to a thickness of 13 μm on an aluminum-deposited polyester film (Metal Me, manufactured by Toray Industries, Inc.) using a bar coater. , and dried at 130°C for 30 minutes to obtain a photoreceptor. Next, using a commercially available electrostatic copying paper tester (SP428 manufactured by Kawaguchi Electric Co., Ltd.), a +6kV corona discharge was performed to positively charge the paper (maximum surface potential +570V).
Using the 2856 W lamp included with SP428 in combination with Toshiba's sharp cut filter and interference filter, the sensitivity at 800 nm was determined to be 2.1 μJ/cm ² . Also, when exposed with only a W lamp without a filter at an illuminance of 10 Lux, the sensitivity was 3 Lux seconds. Next, apply -50V to the aluminum base side of this photoconductor, place it in EG Teveropper (positive polarity conductive liquid toner) manufactured by Minolta Business Machine Sales Co., Ltd. for 30 seconds for bias development, and leave it at room temperature to dry. The surface resistance was measured using an electrometer manufactured by Takeda Riken.
When measured using a combination of TR300C insulation resistance measurement power supply and TR42 ultra-high resistance measurement sample box, the result was 1.4
It was ×10 ⁶ Ω. Next, even if a positive or negative corona discharge (±6kV) is continuously applied to this bias-developed photoreceptor, its surface potential will be +20 to +30 and -20 to -30, respectively.
It only improved by a certain amount. From the above experimental results, if an image is formed on the above-mentioned photoreceptor using conductive liquid toner, the image area (conductive liquid toner area) and non-image area have a large difference in acceptance potential under corona discharge, and electrostatic printing It will be easily understood that it is available as a version. Comparative Example 1 4.5 g of ε-type copper phthalocyanine (εCuPc) manufactured by Toyo Ink Mfg. Co., Ltd. and silicone resin (manufactured by Shin-Etsu Chemical Co., Ltd.)
KR211) and acrylic resin (Aron S1001 manufactured by Toagosei Kagaku Co., Ltd.) in a solid weight ratio of 9:1 was added to 18 g, 67 g of toluene was added, and after dispersion in a ball mill for 10 hours, photoconductivity was obtained. Add 15g of zinc oxide (SAZEX2000, manufactured by Sakai Chemical Co., Ltd.) and disperse the mixture in a ball mill for another 6 hours. Using a bar coater, coat the polyester film (Metal Me, manufactured by Toray Industries, Inc.) on which aluminum has been vapor-deposited to 12 μm.
Apply to the thickness of , dry at 50℃ for 8 hours,
A photoreceptor with εCuPc/ZnO=0.3 (wt) was obtained. Next, using a commercially available electrostatic copying paper tester (SP428 manufactured by Kawaguchi Electric Co., Ltd.), perform a +6kV corona discharge to positively charge the paper, then use the 2856
〓W lamp is used in combination with Toshiba's sharp cut filter and interference filter,
The sensitivity at 800 nm was found to be 5.2 μJ/cm ² . Comparative Example 2 10 g of β-type copper phthalocyanine (βCuPc) manufactured by Toyo Ink Manufacturing Co., Ltd. and silicone resin (manufactured by Shin-Etsu Chemical Co., Ltd.)
76 g of toluene was added to 21.5 g of a mixture of acrylic resin (Aron S1001 manufactured by Toagosei Kagaku Co., Ltd.) and acrylic resin (Aron S1001 manufactured by Toagosei Kagaku Co., Ltd.) at a weight ratio of 9:1, and after dispersion in a ball mill for 10 hours, photoconductive Add 10g of zinc oxide (SAZEX2000, manufactured by Sakai Chemical Co., Ltd.) and disperse the mixture in a ball mill for 6 hours. Using a bar coater, coat the polyester film (Metal Me, manufactured by Toray Industries, Inc.) on which aluminum has been deposited.
Apply to a thickness of 12μ, dry at 50℃ for 8 hours,
A photoreceptor with βCuPc/ZnO=0.5 (wt) was obtained. Next, using a commercially available electrostatic copying paper tester (SP428 manufactured by Kawaguchi Electric Co., Ltd.), perform a +6kV corona discharge to positively charge the paper, and then use the 2856
〓W lamp is used in combination with Toshiba's sharp cut filter and interference filter,
The sensitivity at 800 nm was determined to be 4.5 μJ/cm ² . Example 1 A Canon semiconductor laser beam printer LBP-10 was modified, the photosensitive drum was replaced with an aluminum drum, and only the positive charger, exposure device, and development device were functional.The machine was used in a preliminary experiment. The photoreceptor was grounded and attached to an aluminum drum. The same positive polarity conductive liquid toner used in the preliminary experiment was placed in the developing device. Next, an electric signal was input to operate the machine, and the steps of charging, exposing the image area with semiconductor laser light, and reversing development with conductive liquid toner were completed. Next, the developed photoreceptor was removed from the aluminum drum and dried with warm air to produce an electrostatic printing plate with conductive image areas. This electrostatic printing plate was uniformly subjected to negative corona discharge (-6kV), and a negative type toner Liofax N-1 manufactured by Toyo Ink Manufacturing Co., Ltd. and a carrier manufactured by Nippon Tetsuko Co., Ltd. were used.
Reversal development is performed using a magnetic brush method using a developer consisting of EFV150/250, paper is placed, a positive corona discharge (+6kV) is applied to the paper, the toner is electrostatically transferred to the paper, and the toner is heated and fixed to produce printed matter. I got it. Example 2 Corona discharge (+
6kV) to positively charge the original positive film at 10Lux using a 100W tungsten light source for enlargement.
An electrostatic latent image was formed on the photoreceptor by reverse image projection for 1.5 seconds, and then a visible image was obtained using a one-component conductive magnetic toner having the following composition. Magnetite (black iron oxide) 35 parts Carbon Black 15 parts Polystyrene 40 parts Sumikalon Violet 3RL (manufactured by Sumitomo Chemical)
20 parts The average particle size was 15μ, and the pressed powder had a resistance value of about 10 ⁵ Ωcm. This one-component conductive magnetic toner adhered to the electrostatic latent image area. Next, heating was applied to melt and fix the one-component conductive magnetic toner. This was used as a printing plate for electrostatic printing. Using this printing plate for electrostatic printing, a printed matter was obtained by electrostatic printing using the same method and materials as in Example 1. Example 3 40 parts of metal-free phthalocyanine and 1.5 parts of mononitro copper phthalocyanine were dissolved in 1000 parts of 98% concentrated sulfuric acid with thorough stirring. After pouring the dissolved liquid into 10,000 parts of water and precipitating the phthalocyanine composition,
It was filtered, washed with water, and dried at 120°C under reduced pressure. For 100 parts of the thus obtained composition [] and ε-type copper phthalocyanine (Lionol Blue ER)
100 parts of the mixture was mixed and dispersed in 5,000 parts of methanol to obtain a uniformly mixed dispersion liquid. Then filtered and under reduced pressure
It was dried at 120°C to obtain a mixture []. Next, 4.6 parts of the above mixture [] and 18 parts of a mixture of silicone resin (KR211 manufactured by Shin-Etsu Chemical Co., Ltd.) and acrylic resin (Aron S1001 manufactured by Toagosei Chemical Co., Ltd.) at a solid weight ratio of 9:1. , toluene 67.4
After dispersing in a magnetic ball mill for 30 hours, photoconductive zinc oxide (manufactured by Sakai Chemical Co., Ltd.) was added.
Add 15 parts of SAZEX2000) and disperse the mixture for another 10 hours. Using a bar coater, apply the mixture to a thickness of 14 μm on an aluminum-deposited polyester film (Metal Me manufactured by Toray Industries, Inc.), and heat at 130°C.
A photoreceptor was obtained by drying for 30 minutes. Using this photoreceptor, a printing plate for electrostatic printing was manufactured using the same method and materials as in Example 1. Example 4 40 parts of copper phthalocyanine and 0.5 part of tetracyanocobalt phthalocyanine were dispersed in 200 parts of glacial acetic acid,
10 parts of 98% sulfuric acid was added dropwise while stirring, and after stirring for 10 hours, the solid matter was separated and ammonia gas was passed through it to precipitate a phthalocyanine composition, which was then washed with water and dried at 120°C under reduced pressure. The composition thus obtained was mixed according to the following recipe. Composition [] 3 parts ε-type copper phthalocyanine (manufactured by Toyo Ink Mfg. Co., Ltd.)
Lionol Blue ER) Two-part branched polyester polyol (Desmofene #800 manufactured by Nippon Polyurethane Industries Co., Ltd.) 13 parts Cellsolve acetate 67 parts The above composition was milled in a magnetic ball mill at room temperature for 24 hours, and then photoconductive zinc oxide was prepared. (Manufactured by Sakai Chemical Co., Ltd.
After further kneading, 2 parts of isocyanate (Desmodyur N-75 manufactured by Nippon Polyurethane Industries Co., Ltd.) was added according to the recipe, and aluminum was vapor-deposited using a bar coater. It was coated on a polyester film (Metal Me manufactured by Toray Industries, Inc.) to a thickness of 12 μm and placed in an oven uniformly heated to 120° C. for 30 minutes to obtain a photoreceptor. Next, in a machine similar to that of Example 1, the photoreceptor was attached to an aluminum drum with a ground connection. The positive conductive liquid toner used in the preliminary experiment was placed in the developing device. Next, an electric signal was input to operate the machine, and the steps of charging, exposing the image area with semiconductor laser light, and forming a regular image with conductive liquid toner were completed. Next, the developed photoreceptor was removed from the aluminum drum and dried with warm air to produce a printing plate for electrostatic printing with electrical conductivity in non-image areas. Positive corona discharge (+
6 kV) was uniformly applied, positive development was performed by a magnetic brush method using a developer consisting of the negative type toner and carrier used in Example 1, paper was placed, and a positive corona discharge (+6 kV) was applied to the paper. The toner was electrostatically transferred onto paper and fixed by heating to obtain a printed matter. Example 5 50 parts of trinitrocopper phthalocyanine in 98% concentrated sulfuric acid
It was dissolved in 600 parts with thorough stirring. The dissolved solution was poured into 6000 parts of water to precipitate a composition of α-type trinitrocopper phthalocyanine, which was then filtered, washed with water, and dried at 120° C. under reduced pressure. 100 parts of the composition thus obtained and 100 parts of ε-type copper phthalocyanine were dispersed in 5000 parts of methanol to form a uniform dispersion.
Thereafter, it was filtered and dried at 120°C under reduced pressure to obtain a mixture []. 3 parts of the above mixture [], 18 parts of acrylic resin (Arotap #3211 manufactured by Nippon Shokubai Chemical Co., Ltd.), 34.4 parts of methyl ethyl ketone, and 17.2 parts of n-butyl alcohol.
After dispersing 17.2 parts of Cellsolve Acetate in a porcelain ball mill for 30 hours, 10.2 parts of photoconductive zinc oxide (SAZEX2000 manufactured by Sakai Chemical Co., Ltd.) was added.
Further, the mixed solution dispersed for 10 hours was coated with a bar coater to a thickness of 13μ on carbon paper (thickness 170μ) coated with casein as a water-soluble resin, dried at 70℃ for 8 hours, and exposed to light. I got a body. Next, the photoreceptor was attached to the same machine as in Example 1. The positive conductive liquid toner used in the preliminary experiment was placed in the developing device. Next, the machine was operated to produce a printing plate for electrostatic printing in which the image area was conductive by charging, exposing the non-image area to semiconductor laser light, and applying a regular image to the conductive liquid toner. Example 6 Tetranitrocopper phthalocyanine was prepared in the same manner as in Example 5 to form a mixture []. 3 parts of the above mixture [], 15 parts of acrylic resin (Arotap #3211 manufactured by Nippon Shokubai Chemical Co., Ltd.), 35 parts of methyl ethyl ketone, and 18.4 parts of n-butyl alcohol.
After dispersing 18.4 parts of Cellsolve Acetate in a porcelain ball mill for 30 hours, 10.2 parts of photoconductive zinc oxide (SAZEX2000 manufactured by Sakai Chemical Co., Ltd.) was added.
Further, the mixed solution dispersed for 10 hours was coated with a bar coater to a thickness of 15μ on carbon paper (thickness 170μ) coated with casein as a water-soluble resin, dried at 70℃ for 8 hours, and exposed to light. I got a body. Next, the above photoreceptor was attached to the same machine as in Example 1. The used positive polarity conductive liquid toner was placed in the developing device. Then operate the machine,
By charging, exposing the non-image area to semiconductor laser light, and reversing development using a conductive liquid toner, a printing plate for electrostatic printing in which the non-image area was conductive was manufactured. When the photoreceptors of Comparative Examples 1 and 2 and Examples 1 to 6 were compared, there was a significant difference in photosensitivity, and the results are shown in Table 1. The samples were measured using an electrostatic copying paper tester (SP428 manufactured by Kawaguchi Electric Co., Ltd.).After applying a +6kV corona discharge at a charging speed of 10m/min, after 10 seconds, a 2856〓 W lamp was applied to a Toshiba manufactured Using a combination of a sharp cut filter and an interference filter, a light energy of 4 μW/cm ² was applied, and the photosensitivity was determined by measuring the time it took for the surface potential to decrease to half. 【table】

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is an explanatory diagram showing a state in which a photoreceptor is charged by corona irradiation, and FIG. 2 is an explanatory diagram showing a state in which a photoreceptor is exposed to semiconductor laser light to form an electrostatic latent image. FIG. 3 is an explanatory diagram showing a photoconductor that has been reversely developed with conductive toner, FIG. 4 is an explanatory diagram that shows a photoconductor that has been normally developed with conductive toner, and FIGS. FIG. 3 is an explanatory diagram showing a fixed photoreceptor. 1... Conductive support, 2... Photoconductive layer, 3...
Photoreceptor, 4... Semiconductor laser light, 5... Conductive toner, 6... Conductive portion, 7... Insulating portion, 8
...Printing plate for electrostatic printing.

Claims (1)

[Scope of Claims] 1. The photoreceptor is prepared by disposing, on a conductive support, an ε-type copper phthalocyanine (A), a phthalocyanine having an electron-withdrawing group, or a mixture of a phthalocyanine having an electron-withdrawing group and another phthalocyanine. Using a photoconductive layer in which a mixture of acid-pasted phthalocyanine derivative (B) and zinc oxide are dispersed in a binder resin, the photoreceptor is charged and exposed to light to create an electrostatic potential. A printing plate for electrostatic printing, which is formed by forming an image, developing the electrostatic latent image using a conductive toner, and fixing it. 2. A printing plate for electrostatic printing, characterized in that semiconductor laser light modulated by an electrical signal is used for exposure as described in claim 1.