JP3270634B2 - Photosensitive material for printing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to a photosensitive material for printing having a photoconductive layer provided on a conductive support, particularly a semiconductor laser beam having a long wavelength.
Provided is a photosensitive material for electrophotographic printing having high sensitivity in the near infrared to visible light region, which is applicable to a laser plate making system using (780 nm wavelength) as a light source.

[0002]

2. Description of the Related Art Photosensitive materials having a photoconductive layer comprising a phthalocyanine compound and a binder resin on a conductive support are widely used in the field of printing and the like.
In the field of printing, in particular, after the material is corona-charged, an image is exposed to light using a semiconductor laser light source having an oscillation wavelength of, for example, 780 nm to form an electrostatic latent image, and toner is bound thereon. To visualize the latent image. A printing plate is formed by eluting a portion other than the portion where the toner adheres.

[0003] The elution other than the toner adhering portion, that is, the so-called development, is often performed with an alkaline aqueous solution.
Therefore, the binder resin needs to be alkali-soluble. Conventionally, to make the binder resin alkali-soluble,
Emphasis has been placed on introducing a large amount of hydrophilic functional groups (eg, hydroxyl groups, acid anhydride groups, carboxyl groups and sulfonic acid groups). For example, JP-A-2-210448 and JP-A-5-19514 disclose a phthalocyanine compound and guanidine in an alkali-soluble binder resin such as a carboxylated polyvinyl acetate resin or a styrene-maleic acid copolymer resin. Are shown. Further, Japanese Patent Application Laid-Open No. 4-212966 discloses a phthalocyanine compound dispersed in an alkali-soluble binder resin such as a carboxyl group-containing acrylic resin.

[0004] However, any binder resin design focuses solely on imparting alkali water solubility, and does not improve the dispersibility of phthalocyanine which is a photoconductive substance. Sufficient performance has not been obtained in the characteristics. Many photoconductive substances, particularly phthalocyanines, have a surface hydrophobic substance, and do not easily become a well-dispersed state in a strongly hydrophilic binder, and the storage stability of the coating is poor. Further, since the hydrophilic functional group as described above is adsorbed on or adjacent to the surface of the phthalocyanine pigment, the insulating property of the photoconductive layer is insufficient, which adversely affects electric characteristics (especially, initial potential and dark decay during corona charging).

[0005] The present invention has improved the above disadvantages and has greatly improved the dispersibility of a phthalocyanine compound in a binder resin.
The purpose is to improve the electrical properties of the photoconductive layer.

[0006]

That is, the present invention relates to a photosensitive material comprising a photoconductive layer containing a phthalocyanine compound and a binder resin on a conductive support. Wherein at least one kind of the resin is a radically polymerizable monomer (I) represented by the following general formula:

[0007]

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Wherein R ¹ represents hydrogen or a methyl group, m represents an integer of 2 to 5, and n represents an integer of 0 to 10. Provided is a photosensitive material for printing, wherein the content in the resin is 0.01 to 50% by weight.

It is well known that tetrahydrofuran is a good phthalocyanine dispersion medium. However,
When tetrahydrofuran is blended as a coating solvent, the phthalocyanine crystal transition is promoted, which may result in a decrease in the photoelectric properties of the dried coating film (photoconductive layer) in a short period of time. The period becomes significantly shorter. Also, tetrahydrofuran has a low boiling point (65
° C), it is easily dissipated from the paint into the air, and is removed earlier than the paint film in the heating and drying process, resulting in a drawback of causing poor dispersibility of phthalocyanine in the dry paint film.

The present invention ameliorates the above disadvantages. First, by using a (meth) acrylate monomer having a tetrahydrofurfuryl group as a substituent as a polymer, while improving the adsorptivity to the phthalocyanine powder surface, the binding transition of phthalocyanine in the paint as described above is performed. Suppress the progress of.

Further, since the tetrahydrofurfuryl group is present as a polymer pendant, it does not dissipate from the coating film during heating and drying, so that the dispersibility of phthalocyanine in the dried coating film is not lost. Also, monomer
Since the homopolymer (I) is hydrophobic, it is estimated that the homopolymer has an effect of improving the insulating property in the photosensitive layer. Due to the above effects, the introduction of the homopolymer of the monomer (I) into the binder significantly improved the initial potential during corona charging and the potential retention due to dark decay.

As a result, an electrostatic image having a large difference in shading from the charge density can be obtained on the plate surface by light irradiation with a semiconductor laser or the like. Therefore, the adhesion of the toner is improved, and a clear visible image can be obtained.

Further, when a photoreceptor having a large area such as a printing plate for newspaper printing is required, the photoreceptor is sufficient for a long time (several tens of seconds to several minutes) required for scanning exposure. As a result of maintaining the surface potential, a clear visible image can be formed.

The monomer represented by the general formula (I) is a monomer having a tetrahydrofuran ring at a molecular terminal. Products of this monomer are known. For example, it can be synthesized by the following method.

First step: Ring-opening addition reaction of lactone to (meth) acrylic acid

[0016]

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(Where m and n are as defined above)
If n = 0, this step can be omitted.

The lactone in this case is, for example, β-lactone.
(Propiolactone; m = 2), γ-lactone (butyrolactone; m = 3), δ-lactone (δ-valerolactone; m = 4) ε
-Lactone (ε-caprolactone; m = 5).

Second step: After converting the obtained compound into an acid chloride, an ester bond is formed by a dehydrochlorination reaction with tetrahydrofurfuryl alcohol.

In both the first step and the second step, a heating reaction is carried out in the presence of a radical polymerization inhibitor (such as hydroquinone methyl ether) while protecting the vinyl group.

Specific examples of the monomer (I) include furfuryl
(Meth) acrylate, furfuryl polypropiolactone
(Meth) acrylate, furfuryl polybutyrolactone
(Meth) acrylate, furfuryl poly δ-valerolactone (meth) acrylate, furfuryl poly ε-caprolactone (meth) acrylate and the like.

This monomer is polymerized by a usual radical polymerization method to obtain a homopolymer. Polymerization is a conventional radical polymerization method (e.g., solution polymerization, bulk polymerization, emulsion polymerization,
Suspension polymerization, non-aqueous dispersion polymerization, etc.). An appropriate molecular weight range of the obtained resin is 3,000 to 1,000,000, preferably 10,000, as a number average molecular weight.
00 to 300,000. Number average molecular weight of 3,000
In the following, depending on the amount of addition, there are cases where the photoreceptor resin layer becomes brittle, resulting in insufficient printing durability. In addition, when the resin solution is used in a polymer region of 1,000,000 or more, the handleability is poor due to the high viscosity, and the viscosity of the coating material is undesirably increased.

The binder resin used in the present invention contains another alkali-soluble resin. Specific examples of conventionally common resins having alkali solubility include styrene / maleic acid copolymer, styrene / maleic acid monoester copolymer, (meth) acrylic acid / (meth) acrylic acid ester copolymer, (Meth) acrylic acid / acrylic acid ester / methacrylic acid ester copolymer, styrene / (meth) acrylic acid / (meth) acrylic acid ester copolymer, vinyl acetate / crotonic acid copolymer, vinyl benzoate / crotonic acid Styrene, methacrylate, acrylate, vinyl acetate, vinyl benzoate, etc., and acrylic acid, such as vinyl acetate / crotonic acid / (meth) acrylate copolymer
Methacrylic acid, itaconic acid, crotonic acid, maleic acid,
A copolymer with a carboxylic acid-containing monomer such as fumaric acid or a dibasic acid monoester-containing monomer, or a monomer having a methacrylamide, vinylpyrrolidone, a phenolic hydroxyl group, a sulfonic acid group, or a phosphate group. And copolymers composed of monomers. Of course, the monomer (I) may be included in the alkali-soluble resin C as one of the copolymerization components in the resin composition. Further, Japanese Patent Application Laid-Open No. 4-274
No. 428 and JP-A-4-258956 may be used. Among the alkali-soluble binder resins listed above, those preferably used in the present invention have a glass transition temperature of 40 ° C. or higher, a resin acid value of 50 to 300 and a number average molecular weight of 10,000.
The above resin.

If the glass transition temperature is less than 40 ° C., the resin layer on the support becomes brittle, resulting in insufficient printing durability during printing. If the resin acid value is less than 50, the alkali solubility will be poor, and if it exceeds 300, the alkali solubility of the resin layer will be too strong, so that side etching will easily occur and the image quality will deteriorate. Furthermore, when the number average molecular weight of the resin is less than 10,000, the resin layer becomes brittle and the printing durability becomes insufficient.

The phthalocyanine compounds used in the present invention are generally metal phthalocyanines and metal-free phthalocyanines represented by formula (II):

[0026]

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As metal phthalocyanines, α, β, ε,
Various crystalline forms such as m, π, ρ, and χ or amorphous forms, those substituted or unsubstituted by halogen atoms, and metals such as copper, magnesium, zinc, aluminum, vanadium, molybdenum, manganese, iron, and cobalt , Nickel, titanium or oxides thereof. Further, as the metal-free phthalocyanine, those having an X-type crystal form are preferably used.

In the photoconductive layer, in addition to the phthalocyanine compound which is a charge generating substance, an appropriate amount of various additives for improving charging characteristics or photosensitivity can be used in combination. Specific examples thereof include quinone compounds such as anthraquinone, anzanthrone and pyranthrone; fluorenone compounds such as trinitrofluorenone and tetranitrofluorenone; perinone compounds; perylene compounds; cyanine compounds; bisazo compounds; quinacridone compounds; Compounds Also, electron donating compounds such as hydrazone compounds, triphenylmethane compounds, guanamine compounds, guanidine compounds, thiourea compounds, and thiobarbituric acid derivatives are exemplified. In addition, known additives such as a sensitizer and a plasticizer can be used.

The mixing ratio of the homopolymer to the whole binder resin is 0.01 to 50% by weight, preferably 0.1 to 30% by weight in the total binder resin. When the amount is less than 0.01% by weight, no effect is observed in improving the electrical properties (potential holding properties based on initial charge potential and dark decay) of the prepared photosensitive composition. On the other hand, if it exceeds 50% by weight, on the contrary, the alkali-soluble resin in the composition becomes insufficient, so that the alkali elution property of the composition (coating film) decreases, which is not preferable. The method of blending the homopolymer into the coating composition is as follows:
It is desirable to dissolve the homopolymer in good dissolution, first disperse the phthalocyanine pigment in the resin solution, and then mix other alkali-soluble resins or additives, but more preferably the homopolymer is dried and powdered. Then, if the phthalocyanine pigment is positively combined with the phthalocyanine pigment by mechanically mixing or mechanochemically fusing the phases with each other, it is advantageous for achieving the effects of the present invention.

The weight ratio of phthalocyanine to the entire binder resin in the photoconductive layer is preferably in the range of 1/10 to 2/5. When the phthalocyanine content is less than 1/10, the photosensitivity of the composition is particularly remarkably reduced, and it is difficult to obtain a clear toner image. On the other hand, when the phthalocyanine content exceeds 2/5, the structural viscosity of the coating composition becomes high, and it becomes difficult to apply the coating composition. Also, the coating film after drying
(Photoconductive layer) becomes brittle, and the printing durability when used as a plate material decreases. The photosensitive composition of the present invention may be added, for example, to a solution of a binder resin obtained by dissolving the phthalocyanine compound and optionally an electron-accepting compound and / or an electron-donating compound in a suitable organic solvent. It is prepared by uniformly dispersing with a suitable dispersing device, for example, a paint shaker, a ball mill, a sand mill, an attritor, or the like, applying this on a conductive substrate, and drying by heating. The coating is usually performed using a doctor blade, a bar coater (wire bar), a roll coater, or the like.

Suitable solvents for use in preparing the composition of the present invention include, for example, aromatic hydrocarbons such as benzene, toluene and xylene, ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone, ethyl ether and tetrahydrofuran. Ethers and cyclic ethers such as 1,4-dioxane, esters such as ethyl acetate and butal acetate, cellosolves such as methyl cellosolve, ethyl cellosolve and butyl cellosolve (ethylene glycol monoalkyl ethers)
Or a mixture thereof.

The photosensitive resin plate of the present invention has a photosensitive layer made of the above composition provided on a conductive support. In the case of a single layer type, the thickness of the photosensitive layer is 1 to 20 μm, preferably 2 to 20 μm.
10 μm.

If the thickness of the photosensitive layer is extremely thin beyond the proper range as described above, the surface potential of the photosensitive member becomes low, and only a small amount of toner adheres to the image area due to the toner phenomenon. A complete film of the image is not formed, and a portion where no toner exists, such as a minute void or a pinhole, is generated in the image portion. Therefore, when preparing a printing plate by dissolving and removing the non-image portion of the photoconductor with an alkaline aqueous solution, the alkaline aqueous solution penetrates the voids and pinholes of the toner image and partially dissolves and removes the photosensitive layer of the image. This is not preferred.

Conversely, if the photosensitive layer is thicker than the above-specified range, a toner film can be completely formed on the photoreceptor. Not only is it time-consuming, but also the photosensitive layer in the image area, such as fine lines and fine halftone dots, is easily removed by sand etching, which is not preferable.

Following the application of the above photosensitive composition onto the support, drying is performed to obtain a photosensitive layer.
It is desirable that the temperature is in the range of 0 to 200 ° C, preferably 70 to 150 ° C. The drying time depends on the set temperature, but is preferably about 1 to 30 minutes. When drying is performed at a temperature and time lower than the above drying conditions, a large amount of the residual solvent remains in the photosensitive layer, and the charge retention rate based on corona charging characteristics and dark decay decreases. Further, when the drying is performed at a temperature higher than the above drying conditions for a time, the photosensitive layer is strongly fused to the support due to the high temperature, or the polymerization reaction by the unreacted functional group in the binder resin is promoted. As a result, a change in the crystal form of phthalocyanine results in a decrease in alkali elution properties, a decrease in charging characteristics, and a decrease in light temperature.

As the support of the printing plate of the present invention, for example, a metal plate such as aluminum, a metal foil, a plastic film on which a metal such as aluminum is deposited, or a paper subjected to a conductive treatment is used. Used after hydrophilic treatment. Among these supports, an aluminum plate is preferably used.

As a method for hydrophilically treating the surface of the aluminum plate, a known method such as graining or anodic oxidation can be used. Graining methods include mechanical surface roughening, electrochemical surface roughening, and chemical surface selective dissolution. Known methods such as a ball polishing method, a brush polishing method, a blast polishing method, and a buff polishing method can be used for the mechanical surface roughening method. As the electrochemical surface roughening method, there is a method in which an alternating current or a direct current is used in a hydrochloric acid or nitric acid electrolyte.

The aluminum plate subjected to the above treatment is subjected to anodizing treatment. As the electrolyte used for the anodic oxidation treatment, nitric acid, phosphoric acid, oxalic acid or the like or a mixed acid thereof is used, and the electrolyte and the concentration thereof are appropriately determined depending on the type of the electrolyte. The amount of anodized film is 0.1
It is preferably 0 to 10 g / m ² , and more preferably 0.5 to 5.0 g / m ^2.
Is suitable. Furthermore, an alkali metal silicate aqueous solution or silicate electrodeposited after the anodizing treatment can be used as a suitable support.

[0039]

According to the present invention, since the electrical characteristics of the photoconductive layer can be improved, the surface of the photoconductive layer has a high charge potential over a long period of time after corona charging. As a result, an electrostatic latent image having a large difference in density between the charge densities is obtained. After the toner is bound, an effect of improving the adhesion of the toner is observed, and a clear visible image is obtained. In particular, a clear visible image can be formed on a photosensitive member having a large area, such as a printing plate for newspaper printing, regardless of the length of the scanning exposure time. Further, a high quality printed matter can be obtained from the printing original plate thus improved.

[0040]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail based on embodiments. The present invention is not limited to these examples. All “parts” in each example are “parts by weight” unless otherwise specified.

Production Example 1 (Synthesis example 1 of binder resin) 1 equipped with a stirrer, a Dimroth (cooler), and a nitrogen inlet tube
200 parts of ethyl cellosolve was previously charged in a flask having a capacity of 1 liter, and after the temperature was raised to 85 ° C., 124.8 parts of isobutyl methacrylate, 13.8 parts of ethylhexyl methacrylate, 61.4 parts of methacrylic acid and a radical polymerization initiator V- A mixed solution of 1.4 parts of 59 (2,2'-azobis (2-methylbutyronitrile), manufactured by Wako Pure Chemical Industries) was dropped into the flask over 3 hours from a dropping funnel. Heating was further performed for 3 hours to complete the solution polymerization reaction. The resulting resin had a solid content of 50%, a number average molecular weight of 20,
000, weight average molecular weight 65,000 and acid value 200
Met.

Production Example 2 (Synthesis Example 2 of Binder Resin) In the same manner as in Production Example 1, 200 parts of ethyl cellosolve was charged in a 1-liter flask in advance, heated to 85 ° C., and then separately treated with tetrahydrofurfuryl. 200 parts of methacrylate and 1.4 of a radical polymerization initiator (V-59)
The mixture was dissolved and dropped into the flask over 3 hours from a dropping funnel. After further heating for 3 hours, the solution polymerization reaction was terminated. The obtained resin has a solid content of 50%,
The number average molecular weight was 18,500 and the weight average molecular weight was 62,000.

Production Example 3 (Synthesis Example 3 of Binder Resin) In the same manner as in Production Example 1, 200 parts of ethyl cellosolve was previously charged in a 1-liter flask, heated to 85 ° C., and then separately treated with tetrahydrofurfuryl polypropylene. Olactone methacrylate (propiolactone 10 mol adduct) 20
A solution prepared by mixing and dissolving 0 parts and 1.4 parts of a radical polymerization initiator (V-59) was dropped into the flask over 3 hours from a dropping funnel. Heating was continued for another 3 hours to complete the solution polymerization reaction. The obtained resin had a solid content of 50%, a number average molecular weight of 18,000 and a weight average molecular weight of 54,000.

Production Example 4 (Synthesis Example 4 of Binder Resin) In the same manner as in Production Example 1, 200 parts of ethyl cellosolve was charged in a 1-liter flask in advance, and the temperature was raised to 85 ° C .; ε-caprolactone acrylate (2 mol of ε-caprolactone) 20
A solution obtained by mixing and dissolving 0 parts and 1.4 parts of a radical polymerization initiator (V-59) was dropped into the flask over 3 hours from a dropping funnel. After further heating for 3 hours, the solution polymerization reaction was terminated. The obtained resin had a solid content of 50%, a number average molecular weight of 21,500 and a weight average molecular weight of 68,000.

Production Example 5 (Synthesis example 5 of binder resin) 1 equipped with a stirrer, a Dimroth (cooler), and a nitrogen inlet tube
Pre-ionized water 1 in a liter volume flask
After the temperature was raised to 85 ° C., 100 parts of tetrahydrofurfuryl methacrylate and an emulsifier (New
col271A (Na ・ alkyl ・ diphenyl ・ ether ・
Di-sulfonate), 1 part of Nippon Emulsifier) and 150 parts of ion-exchanged water, pre-emulsion, 2% of ammonium persulfate
After simultaneously dropping 40 parts of the ion exchange aqueous solution over 2 hours, heating and stirring were further continued for 1 hour to obtain a synthetic resin emulsion having a solid content of 25% and an average particle diameter of 160 nm. About 100 g of a dry resin was obtained from the above synthetic resin emulsion by a freeze drying method. The resin had a number average molecular weight of 300,000 as measured by GPC.

Production Example 6 (Synthesis Example 6 of Binder Resin) In the same manner as in Production Example 1, 200 parts of ethyl cellosolve was charged in a 1-liter flask in advance, heated to 85 ° C., and then separately treated with tetrahydrofurfuryl. Methacrylate 13
A mixture of 8.6 parts, 61.4 parts of methacrylic acid and 1.4 parts of a radical polymerization initiator (V-59) was dropped into the flask over 3 hours from a dropping funnel. 3 more
After heating was continued for an hour, the solution polymerization was terminated. The obtained resin had a solid content of 50%, a number average molecular weight of 24,000, a weight average molecular weight of 78,000 and an acid value of 200.

Example 1 Fastgenble-8120 (X-type metal-free phthalocyanine, manufactured by Dainippon Ink), 10 parts, resin solution synthesized in Production Example 1 90 parts, and resin solution 1 synthesized in Production Example 2
After dispersing 0 parts in 240 parts of a xylene / ethyl cellosolve = 2/1 (w / w) mixed solvent, the mixture was charged into a container together with an appropriate amount of glass beads, and then used for a photosensitive layer using a paint shaker (Red Devil, manufactured by Aishin). A paint was prepared. This coating material was applied to an aluminum plate previously subjected to surface hydrophilic treatment using a wire bar (bar coater).
After drying for 5 minutes, an electrophotographic lithographic printing plate having a photosensitive layer thickness of 5 μm was prepared. The charging characteristics and photosensitivity of the printing original plate were measured using "Paper Analyzer EPA-8100" manufactured by Kawaguchi Electric. The measurement conditions were as follows: the surface potential V ₀ (V) of the photoreceptor immediately after applying a corona charging voltage of +6.0 KV,
The surface potential V ₆₀ (V) after 60 seconds had elapsed was measured, and the charge retention of the printing original plate in the dark was evaluated based on the value of V ₆₀ / V ₀ (%).
The light sensitivity was measured by exposing the surface of the charged printing original plate to 780 nm monochromatic light obtained by spectrally separating white light through a filter. With the light intensity at 1.4 Lux,
Exposure amount E1 / 2 (Lux · Sec) required to reduce the surface potential after exposure to half of the initial surface potential, and 4
The residual potential VR ₄₀ (V) at the time of elapse of 0 second was measured.

Based on these measured values, the charging characteristics and photosensitivity of the printing original plate were evaluated, and the results are summarized in Table 1.

Example 2 10 parts of Fast Genble-8120 (X-type metal-free phthalocyanine, manufactured by Dainippon Ink), 70 parts of the resin solution synthesized in Production Example 1, and 3 parts of the resin solution synthesized in Production Example 3
After dispersing 0 part in 240 parts of the mixed solvent shown in Example 1, a coating material was prepared in the same manner as in Example 1, and the charging characteristics and photosensitivity of the sample coated and dried on the support were measured. Table 1 also summarizes the results.

Example 3 10 parts of Fast Gemble-8120 (X type metal-free phthalocyanine, manufactured by Dainippon Ink), 96 parts of the resin solution synthesized in Production Example 1, and 4 parts of the resin solution synthesized in Production Example 4
Parts were dispersed in 240 parts of the mixed solvent described in Example 1,
A coating material was prepared in the same manner as in Example 1, and the charging characteristics and photosensitivity of the sample coated on the support and dried were measured. Table 1 also summarizes the results.

Example 4 10 parts of Fast Gemble-8120 (X-type metal-free phthalocyanine, manufactured by Dainippon Ink), 99 parts of the resin solution synthesized in Production Example 1 and dried resin 1 synthesized in Production Example 5
Parts were dispersed in 240 parts of the mixed solvent described in Example 1,
A coating material was prepared in the same manner as in Example 1, and the charging characteristics and photosensitivity of the sample coated on the support and dried were measured. Table 1 also summarizes the results.

Example 5 Fast Genble-8120 (X-type metal-free phthalocyanine, manufactured by Dainippon Ink) 10 parts, 90 parts of the resin solution synthesized in Production Example 6 and Resin Solution 1 synthesized in Production Example 2
After dispersing 0 part in 240 parts of the mixed solvent shown in Example 1, a coating material was prepared in the same manner as in Example 1, and the charging characteristics and photosensitivity of the sample coated and dried on the support were measured. Table 1 also summarizes the results.

Example 6 10 parts of octafluoro-octakis (phenylthio) zinc phthalocyanine (manufactured by Nippon Shokubai), 10 parts of N, N'-diphenylthiourea, 10 parts of pyranthrone orange 3-4 brom adduct and 10 parts of Production Example 1 After 90 parts of the synthesized resin solution and 10 parts of the resin solution synthesized in Production Example 2 were dispersed in 350 parts of the mixed solvent described in Example 1, the corona voltage was lowered to -6.
A coating material was prepared in the same manner as in Example 1 except that the voltage was changed to 0 KV, and the charging characteristics and the photosensitivity of the sample coated and dried on the support were measured. Table 1 also summarizes the results.

Example 7 First, 10 parts of Fast Gemble-8120 (X-type metal-free phthalocyanine, manufactured by Dainippon Ink) and 1 part of the dry resin synthesized in Production Example 5 were stirred and compounded by a mechanochemical method. And 99 parts of the resin solution synthesized in 240, and 240 parts of the mixed solvent. The charging characteristics and photosensitivity of the sample prepared by applying the prepared coating material on a support and drying were measured. The results are also shown in Table 1.

Comparative Example 1 10 parts of Fast Gemble-8120 (X-type metal-free phthalocyanine, manufactured by Dainippon Ink) and 100 parts of the resin solution synthesized in Production Example 1 were mixed with 240 parts of the mixed solvent 240 shown in Example 1.
After dispersing in a part, a coating material was prepared in the same manner as in Example 1,
The charging characteristics and photosensitivity of the sample coated and dried on the support were measured. Table 1 also summarizes the results.

Comparative Example 2 10 parts of Fast Gemble-8120 (X-type metal-free phthalocyanine, manufactured by Dainippon Ink), 90 parts of the resin solution synthesized in Production Example 1, and 90 parts of the resin solution synthesized in Production Example 6
After dispersing 0 part in 240 parts of the mixed solvent shown in Example 1, a coating material was prepared in the same manner as in Example 1, and the charging characteristics and photosensitivity of the sample coated and dried on the support were measured. Table 1 also summarizes the results.

Comparative Example 3 10 parts of Fast Gemble-8120 (X-type metal-free phthalocyanine, manufactured by Dainippon Ink) and 100 parts of the resin solution synthesized in Production Example 6 were mixed with 240 parts of the mixed solvent shown in Example 1.
After dispersing in a part, a coating material was prepared in the same manner as in Example 1,
The charging characteristics and photosensitivity of the sample coated and dried on the support were measured. Table 1 also summarizes the results.

Comparative Example 4 10 parts of octafluoro-octakis (phenylthio) zinc phthalocyanine (manufactured by Nippon Shokubai), 10 parts of N, N'-diphenylthiourea, 10 parts of pyranthrone orange 3-4 brom adduct and 10 parts of Production Example 1 After dispersing 100 parts of the synthesized resin solution in 340 parts of the mixed solvent described in Example 1, a coating material was prepared in the same manner as in Example 1, applied to a support, and dried. The charging characteristics and photosensitivity were measured according to the following. Table 1 also summarizes the results.

[0059]

[Table 1]

Example 8 A scanning exposure type plate making machine “1440EZ” using a semiconductor laser having a wavelength of 780 nm as a light source was applied to the printing original plate prepared in Example 1.
A clear toner image was formed by the operations of charging, exposure, liquid phenomenon, and fixing using a "plate setter" (manufactured by Printware, USA) and a liquid developer.

After that, the photosensitive layer in the non-image area where no toner is adhered is dissolved and removed using an alkaline developer (Printer for 1440EZ) manufactured by Printware of the United States, and then a protective treatment with a gum solution is performed. To prepare a lithographic printing plate having a toner image left as an image area.

Each of the obtained printing plates was mounted on a small offset printing machine, Hamadastar 700CDX, Hamada Printing Machinery Co., Ltd., and printed on high quality paper using a commercially available ink. As a result, any of the printing plates can be cleaned neatly without staining the non-image area.
100,000 sheets were printed.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-358156 (JP, A) JP-A-5-80545 (JP, A) JP-A-54-1633 (JP, A) JP-A-53-1983 40529 (JP, A) JP-A-53-58240 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 5/00 CA (STN)

Claims (2)

(57) [Claims] 1. A photosensitive material comprising a photoconductive layer containing a phthalocyanine compound and a binder resin on a conductive support, wherein the binder resin is composed of a plurality of kinds of resins, and Is a radically polymerizable monomer (I) represented by the following general formula: (Wherein, R ¹ represents hydrogen or a methyl group, and m represents 2 to 5
And n represents an integer of 0 to 10. A photosensitive material for printing, characterized in that the content of the homopolymer in the total binder resin is 0.01 to 50% by weight. 2. The photosensitive material according to claim 1, wherein the photoconductive layer further contains an electron accepting compound and / or an electron donating compound.