JP2005111821A - Method for installing lithographic plate material, platemaking method, printing method and printing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printing method for attaining a stable printed matter being excellent in a registering accuracy and free from a printing stain, and a printing system. <P>SOLUTION: In this method for installing a lithographic plate material, the lithographic plate material of which the base material is a plastic is wound around a cylinder of a printing machine and then fixed to the cylinder by electrification. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for installing a lithographic printing plate material based on plastic in a printing press cylinder, a plate making method using the lithographic printing plate material, a printing method, and a printing machine for simply performing installation.

  In the past, lithographic printing plate materials were mainly made of aluminum, but the recent trend toward small lots and lots in printing orders has led to the spread of lithographic printing plate materials that are light and excellent in handling. I'm starting.

  When printing multicolor images using a lithographic printing plate material based on plastic, plate elongation and deterioration of register accuracy due to the low strength of the plastic substrate relative to the aluminum substrate are problematic. It has become.

  As one of the solutions, a silver salt diffusion transfer type lithographic printing plate material based on polyethylene naphthalate is disclosed (for example, see Patent Document 1). Polyethylene naphthalate is superior in strength to polyethylene terephthalate often used in the market, and is advantageous in obtaining registration accuracy. However, polyethylene naphthalate has a high raw material cost and is generally difficult to use.

On the other hand, a method of attaching a lithographic printing plate using paper or a plastic resin film as a support to a cylinder using a double-sided pressure-sensitive adhesive sheet is disclosed (for example, see Patent Document 2). According to this, the adhesion of the lithographic printing plate to the cylinder is improved, and it is possible to ensure registration accuracy. However, skill is required at the time of installing the lithographic printing plate, and it may be distorted and attached at the time of installation. In this case, even if the printing press is registered, the registration mark cannot be corrected.
JP 7-64290 A JP 2002-307858 A

  The present invention is a method for printing using a lithographic printing plate material based on plastic, and particularly when printing a multicolor image, it is possible to obtain a stable printed matter that has excellent registration accuracy and does not cause printing stains. It is an object to provide a printing method and a printing system.

The above problem could be solved by the following configuration.
(Claim 1)
A method of installing a lithographic printing plate material, comprising: winding a lithographic printing plate material based on plastic around a cylinder of a printing machine; and fixing the lithographic printing plate material to the cylinder by charging.
(Claim 2)
After the lithographic printing plate material is wound around a cylinder of a printing press, a roller-like member having a surface resistivity of 1 × 10 ¹⁰ Ω / cm ² or more and less than 1 × 10 ²⁰ Ω / cm ² is brought into contact with the lithographic printing plate material. The lithographic printing plate material installation method according to claim 1, wherein the lithographic printing plate material is charged by rotating the cylinder one or more times and fixed to the cylinder by charging.
(Claim 3)
The lithographic printing plate material installation method according to claim 1 or 2, wherein the lithographic printing plate material is a heat mode recording material.
(Claim 4)
A lithographic printing plate material based on plastic is fixed to a cylinder of a printing machine by the installation method of the lithographic printing plate material according to any one of claims 1 to 3, and then laser irradiation is performed on the cylinder. A plate making method comprising recording an image on the lithographic printing plate material.
(Claim 5)
Supplying ink and dampening water to the lithographic printing plate material made by the plate making method according to claim 4 to form an image on the lithographic printing plate material, and transferring the image to a sheet-like substrate A printing method characterized by the above.
(Claim 6)
In addition to the ink form roller and the water form roller, a roller having a surface specific resistance that can be nipped in a cylinder and has a surface specific resistance of 1 × 10 ¹⁰ Ω / cm ² or more and less than 1 × 10 ²⁰ Ω / cm ^2. A printing machine characterized by comprising.

  The registration method of the lithographic printing plate material of the present invention, the plate making method, and the printing method can stabilize the registration system from the beginning, and can provide a printed matter that does not deteriorate even when the number of printed sheets advances.

  Hereinafter, the present invention will be described in detail.

  The present invention relates to a method for fixing a lithographic printing plate material based on plastic to a cylinder of a printing press.

  In the present invention, as a method of fixing a lithographic printing plate material based on plastic to a cylinder of a printing machine, a method of fixing using a force due to electrification is a special treatment (adhesive layer is applied to the lithographic printing plate material). Etc.) (preferably, etc.).

  In the present invention, as a method of charging the lithographic printing plate material on the cylinder, a method of generating static electricity by contacting the lithographic printing plate material wound on the cylinder with a member having low conductivity is used.

In a method of generating static electricity by contacting a lithographic printing plate material wound on a cylinder with a member having low conductivity, plastic or rubber such as polyethylene, polypropylene, polyethylene terephthalate, etc. can be used as the member having low conductivity. . In particular, polypropylene and polystyrene are preferable because of their high surface resistivity. In the present invention, the surface specific resistance is preferably 1 × 10 ¹⁰ Ω / cm ² or more and less than 1 × 10 ²⁰ Ω / cm ² . If it is lower than this range, the lithographic printing plate material is insufficiently charged and cannot be fixed firmly.

  In the present invention, the lithographic printing plate material is charged by rotating the cylinder while contacting the lithographic printing plate material wound on the cylinder with the roller-like member having the above-mentioned surface resistivity, and fixed to the cylinder by charging. However, it is more preferable in that the strain of the planographic printing plate material can be removed in parallel (Claim 2).

  FIG. 1 shows an example of a printing apparatus suitable for fixing the planographic printing plate material of the present invention to a cylinder.

Reference numerals 1 and 1 'denote charging rollers having polystyrene on the surface having a surface specific resistance in the range of 1 × 10 ¹⁰ Ω / cm ² or more and less than 1 × 10 ²⁰ Ω / cm ² . First, a planographic printing plate material is wound around a clamp 201 of a cylinder. Next, the cylinder 2 is rotated while contacting the charging roller 1 described above. Rotating the cylinder at least 1 rotation, preferably 2 rotations or more, makes the lithographic printing plate material sufficiently charged and sufficiently fixed to the cylinder, and removes distortion of the lithographic printing plate material. It is preferable in terms.

  In the present invention, it is preferable that the lithographic printing plate material contains a plastic film substrate and can form an image by heat mode recording, without fear of fogging due to sparks that may be generated by charging.

<Configuration of planographic printing plate material capable of heat mode recording>
In the present invention, various configurations can be used as an image forming structure by heat mode recording provided on a plastic substrate.

For example,
(A) A layer having a hydrophilic layer on which a heat sensitive layer whose solubility in an alkaline aqueous solution is changed by heat mode recording is further laminated. This configuration is described in Japanese Patent Application Laid-Open No. 2000-221666.
(B) A material having a hydrophilic layer, and a thermoplastic or heat-meltable substance maintaining a particle shape, a hydrophobic precursor, or a heat-sensitive layer containing microcapsules is laminated thereon. . In this mode, after heat mode recording, development processing can be performed with dampening water or / and ink from a printing press, and plate making and printing can be performed substantially without requiring a development step. This configuration is disclosed in JP-A-9-123387, JP-A-2001-96710, JP-A-2001-334766, JP-A-2002-361996, JP-A-2002-178655, and the like. These are of the type that can be made by performing development processing on a printing press.
(C) What has a hydrophilic layer and contains the substance which can be switched to lipophilicity by heat in this hydrophilic layer is mentioned. This form can be printed after the heat mode recording without developing. These are types that can be made by phase change.
(D) What has two layers which show different affinity with respect to ink is mentioned. In this mode, printing is possible by removing one of the two layers by ablation by heat mode recording and imparting different affinities to the ink in the recorded area and the unrecorded area. These are types that can be made by ablation.
Etc.

  Among these, in the present invention, the configurations of (b), (c), and (d) can be printed without using an automatic developing machine, and are suitable for a plate making method and a printing method of a planographic printing plate material described later. ing.

  (B) A type capable of making a plate by development on a printing press (having a hydrophilic layer, and further comprising a thermoplastic or hot-melt material or microcapsule or hydrophobic precursor having a particle shape maintained thereon) The one having a heat-sensitive layer laminated thereon will be described in more detail.

<Hydrophilic layer>
In this configuration, usable hydrophilic layers include those composed of hydrophilic resin, self-forming fine particles and inorganic fine particles.

  Examples of usable hydrophilic resins include polyvinyl alcohol, acrylic copolymers, polyurethanes, and cellulose derivatives. Polyvinyl alcohol having a saponification degree of 95% or more is preferable. Further, those partially modified with a carboxyl group can also be used. As the acrylic copolymer, a monomer having a highly hydrophilic functional group synthesized at a high content can be used. Examples of the highly hydrophilic monomer include acrylamide, methylol acrylamide, methylol methacrylamide, acrylic acid, methacrylic acid. , Hydroxyethyl acrylate, hydroxyethyl methacrylate, and monomers containing ammonium and phosphonium salts, monomers containing sulfonic acid groups, phosphonic acid groups, and phosphoric acid groups. A copolymer obtained by copolymerizing with a polymer and then converting the hydrophilic functional group into a salt can also be used. As the polyurethane, those containing a hydrophilic functional group such as a carboxyl group, a phosphoric acid group, a sulfonic acid group, an amino group or a salt thereof, a hydroxyl group, an amide group, or a polyoxyethylene group in the side chain can be used. Examples of the cellulose derivative include hydroxyethyl cellulose, carboxymethyl cellulose, hydroxypropyl methyl cellulose, hydroxypropyl cellulose and the like.

  Examples of usable self-forming fine particles include alumina sol and colloidal silica, and colloidal silica having a particle diameter of 50 nm or less is particularly preferred from the viewpoint of securing the hydrophilic layer coating film strength and hydrophilicity. Specifically, the “Snowtex” series manufactured by Nissan Chemical Industries, Ltd. can be used. Necklace-shaped colloidal silica can also be used in order to achieve both moderate coating strength and water retention. Necklace-shaped colloidal silica is a general term for an aqueous dispersion of continuous spherical silica having a primary particle diameter of the order of nm. Specific examples of the colloidal silica in the form of necklace include “Snowtex-PS” series manufactured by Nissan Chemical Industries, Ltd. Alkaline product names of the series include “Snowtex-PS-S (average particle size in a connected state is about 110 nm)”, “Snowtex-PS-M (average particle size in a connected state is about 120 nm)” And “Snowtex-PS-L (average particle size in a connected state is about 170 nm)”, and acidic products corresponding to these are “Snowtex-PS-SO” and “Snowtex-PS-”, respectively. "MO" and "Snowtex-PS-LO". Here, self-forming refers to the production of a coating film having a dry film thickness of about 1.0 μm and drying at 100 ° C. for 3 minutes, and the coating film is immersed in water for 10 minutes. A film that does not cause defects in the coating even when rubbed with a sponge is regarded as self-forming.

  The above-mentioned hydrophilic resin and self-forming fine particles may be used in combination.

  Examples of inorganic fine particles that can be used in the hydrophilic layer include calcium carbonate, barium sulfate, silica, titanium oxide, clay, and alumina. The mechanical strength improvement, hydrophilicity, water retention improvement, and desensitization treatment described later are effective. Silica, alumina, titanium oxide and zinc oxide are preferable from the viewpoint of exhibiting the above. The average particle size of the inorganic particles is preferably 0.01 μm to 10 μm, and more preferably 0.05 μm to 5 μm.

  The ratio of the above-mentioned hydrophilic resin or self-film-forming fine particles and inorganic fine particles is 2-50: 10-50 in terms of mass ratio, ensuring the mechanical strength and water retention of the hydrophilic layer, and image durability (hereinafter referred to as “image durability”). This is preferable for ensuring surface irregularities for the purpose of image printing durability.

  For the purpose of ensuring further mechanical strength, the hydrophilic layer of the present invention may be provided with a crosslinked structure using a crosslinking agent. As the crosslinking agent, formaldehyde, epoxy resin, melamine resin, glyoxal, polyisocyanate, hydrolyzed tetraalkylorthosilicate and the like can be used. In the present invention, the content ratio of the crosslinking agent in the hydrophilic layer is preferably 0 to 1% by mass.

The applied amount per 1 m ^{2 of the} hydrophilic layer is preferably 0.5 g to 10 g, more preferably 1.0 g to 5 g.

<Thermosensitive layer>
-Thermoplastic or heat-meltable material in the form of particles-
Examples of the particle-shaped thermoplastic or heat-meltable substance contained in the heat-sensitive layer laminated on the hydrophilic layer include those prepared from known thermoplastic resins, synthetic rubbers, and waxes in the particle shape.

  Examples of the thermoplastic resin include acrylic resins, styrene-acrylic resins, polyesters, polyurethanes, polyethers, polyethylene, polypropylene, polystyrene, ionomer resins, vinyl acetate resins, vinyl chloride resins, and the like.

  Synthetic rubbers include polybutadiene, polyisoprene, polychloroprene, styrene-butadiene copolymer, acrylic ester-butadiene copolymer, methacrylic ester-butadiene copolymer, isobutylene-isoprene copolymer, acrylonitrile-butadiene copolymer. Examples thereof include a polymer, an acrylonitrile-isoprene copolymer, and a styrene-isoprene copolymer.

  The above-mentioned thermoplastic resins or synthetic rubbers have a melting point or softening point of 60 ° C. or higher, and when the film itself is a contact angle with water of 50 ° or higher in terms of image SN and sensitivity. It is advantageous.

  As waxes, natural wax such as carnauba wax, beeswax, whale wax, beeswax, jojoba oil, lanolin, ozokerite, paraffin wax, montan wax, candelin wax, ceresin wax, microcrystalline wax, rice wax, polyethylene wax Fischer-Tropsch wax, montan wax derivatives, paraffin wax derivatives, microcrystalline wax derivatives, higher fatty acids and the like. Among these, the melting point is preferably in the range of 50 ° C. to 150 ° C., and the melt viscosity at 140 ° C. is preferably 0.02 Pa · s or less. It is preferable in terms of image SN and sensitivity. Moreover, it is preferable in terms of printing durability that the penetration specified in JIS K2530-1976 is 1 or less.

  Carnauba wax, candelilla wax, FT wax and the like are preferable as the heat-meltable substance satisfying the above various characteristics.

  In this configuration, the average particle diameter of the thermoplastic or hot-melt material contained in the heat-sensitive layer is preferably 0.1 μm to 0.5 μm. These physical properties are important for obtaining good printing durability. The content of the thermoplastic or heat-meltable substance having a particle shape contained in the heat-sensitive layer is preferably 40% by mass to 100% by mass.

-Hydrophobic precursor-
As the hydrophobic precursor that can be used in this configuration, any precursor that exhibits an affinity for printing ink by heat can be used. For example, a polymer containing an aryldiazosulfonate group is given by the following formula.

In the formula, R ₀ , R ₁ and R ₂ each independently represent a hydrogen atom, an alkyl group, a nitrile group or a halogen atom, L represents a divalent linking group, n represents 0 or 1, and A represents an aryl. The group M represents a cation.

L represents — (X) _t —CONR ₃ —, — (X) _t —COO—, —X— or — (X) _t —CO—, wherein t represents 0 or 1, R ₃ represents hydrogen, An alkyl group or an aryl group, and X represents an alkylene group, an arylene group, an alkyleneoxy group, an aryleneoxy group, an alkylenethio group, an arylenethio group, an alkyleneamino group, an aryleneamino group, oxygen, sulfur or an amino group. It is preferable to show a divalent linking group selected from the group consisting of

  A preferably represents an unsubstituted aryl group, for example an unsubstituted phenyl group, or an aryl group substituted by one or more alkyl, aryl, alkoxy, aryloxy or amino groups, for example phenyl.

M preferably represents a cation such as NH ₄ ⁺ or a metal ion such as Al, Cu, Zn, alkaline earth metal or alkali metal cation.

  The polymer having an aryl diazosulfonate unit is preferably obtained by radical polymerization of the corresponding monomer. Monomers suitable for use in accordance with the present invention are disclosed in EP-A 339393 and EP-A 507008. Specific examples are as follows:

  For example, aryl diazosulfonate monomers as disclosed above can be homopolymerized, or with other aryl diazosulfonate monomers, and / or vinyl monomers such as (meth) acrylic acid or esters thereof (meta ) It can be copolymerized with acrylamide, acrylonitrile, vinyl acetate, vinyl chloride, vinylidene chloride, styrene, alpha-methylstyrene and the like. However, in the case of copolymers, care must be taken not to compromise the water solubility of the polymer. The amount of aryl diazosulfonate groups in the polymer is preferably 10 mol% to 60 mol%.

-Microcapsules-
Examples of the microcapsules that can be used in this configuration include those that contain a substance having a heat-reactive functional group therein. Examples of the thermally reactive functional group include a polymerizable unsaturated group, an isocyanate group, an epoxy group, a hydroxyl group, a carboxyl group, a methylol group, and an amino group diazosulfonate group. From a practical sensitivity, an isocyanate group or a diazosulfonate group is used. Particularly preferred.

  Examples of the compound containing an isocyanate group include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4′-diphenylmethane diisocyanate, 1,5-naphthalene diisocyanate, tolidine diisocyanate, 1,6-hexamethylene diisocyanate. , Isophorone diisocyanate, xylylene diisocyanate, lysine diisocyanate, triphenylmethane triisocyanate, bicycloheptane triisocyanate and the like.

  As the compound containing a diazosulfonate group, the above-mentioned hydrophobic precursor can be used as it is.

  A known method can be used as a method for producing a microcapsule encapsulating the above-mentioned substance having a thermoreactive functional group or a hydrophobic precursor. For example, as a method for producing a microcapsule, US Pat. No. 2,800,457 can be used. , Method using coacervation found in U.S. Pat. No. 2,800,458, British Patent 990,443, U.S. Pat. No. 3,287,154, Japanese Patent Publication No. 38-19574, No. 42-446, No. 42-711, a method based on an interfacial polymerization method, US Pat. Nos. 3,418,250 and 3,660,304, a method based on polymer precipitation, and US Pat. No. 3,796,669. A method using an isocyanate polyol wall material, a method using an isocyanate wall material found in US Pat. No. 3,914,511, No. 4,001,140, U.S. Pat. No. 4,087,376, U.S. Pat. No. 4,089,802, a method using a urea-formaldehyde type or urea formaldehyde-resorcinol type wall forming material, U.S. Pat. No. 4,025, No. 445, a method using a wall material such as melamine-formaldehyde resin, hydroxycellulose, etc., Japanese Patent Publication No. 36-9163, No. 51-9079, in situ method by monomer polymerization, British Patent No. 930,422, US The spray drying method found in Japanese Patent No. 3,111,407 and the electrolytic dispersion cooling method found in British Patent Nos. 952,807 and 967,074 are not limited thereto.

<Water-soluble resin>
The heat-sensitive layer according to this configuration may contain a water-soluble resin as an anti-fusing agent for heat-fusible particles during storage at room temperature. Available water-soluble resins include water-soluble (co) polymers such as synthetic homo- or copolymers such as polyvinyl alcohol, poly (meth) acrylic acid, poly (meth) acrylamide, polyhydroxyethyl (meth) acrylate, polyvinylmethyl. Ethers or natural binders such as gelatin, oligosaccharides, polysaccharides such as dextran, pullulan, cellulose, gum arabic, arginic acid, polyethylene glycol and polyethylene oxide can be used. The content of the water-soluble resin contained in the heat-sensitive layer is preferably 0% by mass to 50% by mass.

In the present invention, the amount of the heat sensitive layer is 0.1 g to 1.0 g per 1 m ² . If it is out of this range, it is difficult to obtain printing durability.

<Photothermal conversion agent>
In this configuration, when image formation is performed using light-heat conversion by laser irradiation, the hydrophilic layer or the heat-sensitive layer preferably contains a light-heat conversion agent.

  As the photothermal conversion agent that can be used, those having an absorption band in the near infrared light are preferable. For example, carbon black, cyanine dye, polymethine dye, azurenium dye, squarylium dye, thiopyrylium dye, naphthoquinone dye, anthraquinone Organic compounds such as dyes, phthalocyanine-based, azo-based, thioamide-based organometallic complexes, metals such as Co, Cr, Fe, Mn, Ni, Cu, Ti, and oxides, nitrides, or oxynitrides thereof Can be mentioned. Specifically, JP-A-63-139191, JP-A-64-33547, JP-A-1-160683, JP-A-280750, JP-A-1-293342, JP-A-2-2074, JP-A-3-26593, Described in 3-30991, 3-34891, 3-36093, 3-36094, 3-36095, 3-42281, 3-97589, 3-103476, etc. The compound of this is mentioned. These can be used alone or in combination of two or more.

  In the present invention, the content ratio of the photothermal conversion agent contained in the hydrophilic layer or the heat-sensitive layer is preferably 3% by mass to 20% by mass.

  (C) The type capable of making a plate by phase change (having a hydrophilic layer and containing a substance that can be switched to lipophilicity by heat in the hydrophilic layer) will be described in more detail.

  As a material constituting the hydrophilic layer in this configuration, the material used for the hydrophilic layer (b) described above can be used as appropriate. Further, as the substance that can be switched to lipophilicity by heat, the above-mentioned hydrophobic precursor or microcapsule (b) can be used as it is.

  In this configuration, the ratio of the material constituting the hydrophilic layer and the substance capable of switching to lipophilicity that can be placed in the hydrophilic layer is 80:20 to 50:50 by mass ratio.

  In this configuration, the hydrophilic layer can contain a photothermal conversion agent, and the photothermal conversion agent (b) described above can be used as it is. In this case, the content ratio of the photothermal conversion agent with respect to the total mass of the hydrophilic layer is 5% by mass to 20% by mass.

  (D) The type capable of making a plate by ablation (having two layers having different affinity for ink) will be described in more detail.

  In this configuration, as a combination of two layers having different affinities for the ink, those obtained by sequentially laminating the following configurations on the substrate can be used.

(A) Ink affinity layer-hydrophilic layer (b) Hydrophilic layer-ink affinity layer In the configuration of (d), the ink affinity layer may be attached with printing ink. No. 22903, various photosensitive polymers exposed and cured, epoxy resin disclosed in JP-A No. 62-50760, thermally cured, JP-A No. No. 63-133151, hardened gelatin, and further one using urethane resin and silane coupling agent disclosed in Japanese Patent Laid-Open No. 3-200265 and Japanese Patent Laid-Open No. 3-273248 And those using the urethane resin disclosed in the above. In addition, gelatin or casein hardened is also effective.

The coating amount of the ink affinity layer is suitably 0.1 to 10 g / m ² in terms of dry mass, preferably 0.2 to 8 g / m ² , more preferably 0.5 to 5 g / m ^2. It is.

  Further, the substrate can be used as it is as long as it has the property of adhering ink.

  As the hydrophilic layer in this configuration, the hydrophilic layer shown in the configuration (b) can be used as it is.

  In this configuration, in order to facilitate image formation by ablation of the laser irradiation portion, the above-described ink repellent layer, ink affinity layer, or hydrophilic layer contains the photothermal conversion agent shown in (b). It can be made. In this case, it is preferable that a photothermal conversion agent is 5 mass%-50 mass% with respect to the total mass of each layer. For the same purpose, an ablation layer may be provided between the two laminated layers.

  For the ablation layer, the photothermal conversion agent shown in (b) is made of cellulose derivatives such as cellulose, nitrocellulose and ethyl cellulose, homopolymers and copolymers of acrylic ester, and methacrylate esters such as polymethyl methacrylate and polybutyl methacrylate. Homopolymers and copolymers, acrylic acid ester-methacrylic acid ester copolymers, homopolymers and copolymers of styrene monomers such as polystyrene and α-methylstyrene, polyisoprene and styrene-butadiene copolymers, etc. Various synthetic rubbers, homopolymers of vinyl esters such as polyvinyl acetate, vinyl ester-containing copolymers such as vinyl acetate-vinyl chloride copolymer, various condensation polymers such as polyurea, polyurethane, polyester and polycarbonate, And "J Imaging Sci., P59-64, 30 (2), (1986) (Frechet et al.) "," Polymers in Electronics Symposium Series, P11, 242, T. Davidson, Ed., ACS Washington, DC (1984) ". Willson) ”and“ Microelectronic Engineering, P3-10, 13 (1991) (E. Reichmanis, L. F. Thompson) ”, and mixed and coated with binders used in the so-called“ chemical amplification system ”. Things. In this case, the mass ratio of the photothermal conversion agent and the binder is 10:90 to 70:30. Moreover, when comprising an ablation layer with a photothermal conversion agent and a binder, a various crosslinking agent can be added in order to improve coating-film intensity | strength and adhesiveness with the laminated | stacked other layer. As the crosslinking agent that can be used, formaldehyde, epoxy resin, melamine resin, glyoxal, polyisocyanate, hydrolyzed tetraalkylorthosilicate, and the like can be used.

  Another form of the ablation layer includes a method of forming metal-containing fine particles capable of photothermal conversion by vapor deposition or sputtering. Available metal-containing fine particles include metals such as aluminum, titanium, tellurium, chromium, tin, indium, bismuth, zinc, lead, alloys thereof, metal oxides, metal carbides, metal nitrides, metal borides, metals Such as fluoride. A thin film can be formed by vapor deposition or sputtering. In this case, the film thickness is 5 nm to 100 nm, preferably 10 nm to 80 nm.

<Plastic substrate>
The plastic substrate in the present invention will be described.

  As the plastic substrate, when using an apparatus related to plate making, a known one can be used as long as it is easy to handle and excellent in mechanical strength. Polyester, polyimide, polyamide, polycarbonate, polysulfone, polyphenylene oxide, cellulose esters, and the like can be used as the resin that can be used for the plastic substrate. Among them, polyester is particularly preferable in terms of mechanical strength.

  Although it does not specifically limit as polyester, It is what has a dicarboxylic acid component and a diol component as main structural components, for example, polyethylene terephthalate (henceforth abbreviated as PET), polyethylene naphthalate (henceforth) And may be abbreviated as PEN). Preferably, PET or a copolymer or blended polyester having a mass ratio of constituents in the whole polyester as a main constituent component of PET or a portion comprising PET is 50% by mass or more.

  PET is polymerized with terephthalic acid and ethylene glycol, and PEN polymerized with naphthalenedicarboxylic acid and ethylene glycol as constituent components. A dicarboxylic acid or diol constituting PET or PEN may be polymerized by mixing another suitable one kind or two or more kinds of third components. As a suitable third component, a divalent ester-forming functional group may be used. Examples of the dicarboxylic acid having a group include the following. Terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, diphenylsulfone dicarboxylic acid, diphenylether dicarboxylic acid, diphenylethanedicarboxylic acid, cyclohexanedicarboxylic acid, diphenyldicarboxylic acid, diphenylthioether dicarboxylic acid Examples thereof include acid, diphenyl ketone dicarboxylic acid, and phenylindane dicarboxylic acid. Examples of glycols include propylene glycol, tetramethylene glycol, cyclohexanedimethanol, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxyethoxyphenyl) propane, and bis (4- Hydroxyphenyl) sulfone, bisphenol full orange hydroxyethyl ether, diethylene glycol, neopentyl glycol, hydroquinone, cyclohexanediol, and the like. As the third component, a polyfunctional carboxylic acid or a polyhydric alcohol can also be mixed, but these can be mixed in an amount of about 0.001 to 5% by mass with respect to all the polyester components.

  The method for polymerizing polyester is not particularly limited, and can be produced according to a conventionally known polyester polymerization method.

  As a film forming means for the base material, a known method is adopted. After melting the polyester resin, the sheet is extruded on a casting drum which is extruded from a T-die and adjusted to a glass transition temperature (Tg) -50 ° C. to Tg. It can be produced by forming and further stretching. In the present invention, it is preferable to heat-treat the polyester film after stretching and heat setting in order to stabilize the dimensions during printing and prevent color misregistration during color printing.

  The thickness of the plastic substrate used in the present invention is preferably in the range of 80 to 400 μm, more preferably 120 to 300 μm. If it is this range, the waist | lumps as a base material can be ensured and it will become easy to handle as a lithographic printing plate material. The thickness distribution is preferably 10% or less.

<Plate making method, printing method>
The lithographic printing plate material is preferably wound around a cylinder, fixed to the cylinder by charging, and then image-formed (plate making) by laser irradiation. This eliminates the need for registering operations during printing.

  B in FIG. 1 is a laser light source. The laser light source that can be used in the present invention can be appropriately selected depending on the absorption characteristics of the photothermal conversion agent, and those having a wavelength in the near infrared are particularly suitable for heat mode recording. A semiconductor laser and a semiconductor-excited solid-state laser (YAG laser) Etc.) are preferably used.

  The lithographic printing plate material fixed to the printing press cylinder and irradiated with the image has a dampening solution 108 (the above-mentioned (a), (b), (c) and (d) (b) (c). If a lithographic printing plate material is used} and printing ink 114 is fed through a number of rollers to form an ink image on the lithographic printing plate material, then the image is passed through a blanket 106 (if necessary (Without using a blanket) and transfer to a sheet-like substrate such as paper. By repeating this, printing is performed.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these.

Example 1
<Preparation of lithographic printing plate material>
After a corona discharge treatment was applied to a PET substrate having a thickness of 188 μm and a length of 1000 m, the first undercoat layer coating solution having the following composition was dried at a temperature of 20 ° C. and 55% RH by a wire bar to give a film thickness of 0.00. It apply | coated so that it might become 4 micrometers. Thereafter, the first undercoat layer was applied by passing the drying zone set at 140 ° C. having a length of 15 m at a conveyance speed of 15 m / min.

  Next, the surface coated with the first undercoat layer is subjected to corona discharge treatment, and then the following second undercoat layer coating solution is dried by an air knife method in an atmosphere of 35 ° C. and 22% RH. It was applied so that the thickness was 0.1 μm. Thereafter, a 15 m long drying zone set at 140 ° C. is passed at a conveying speed of 15 m / min, a second undercoat layer is applied, and an undercoat layer comprising a first undercoat layer and a second undercoat layer Formed.

(Composition of the first undercoat layer coating solution)
Acrylic latex particles: n-BA / tert-BA / St / HEMA = (28/22/25/25) 36.9 parts by mass Surfactant (A) 0.36 parts by mass Hardener (a) 0.98 Part by mass Distilled water was added to the above material to make 1000 ml, which was used as the first undercoat layer coating solution.

(Represents n-BA: n-butyl acrylate, tert-BA: tert-butyl acrylate, St: styrene, HEMA: hydroxyethyl methacrylate, respectively)
(Composition of the second undercoat layer coating solution)
Gelatin 9.6 parts by mass Surfactant (A) 0.4 parts by mass Hardener (b) 0.1 part by mass Distilled water was added to the above material to make 1000 ml, which was used as the second undercoat layer coating solution.

<Coating of hydrophilic layer>
The following hydrophilic layer coating solution is applied onto a PET base material provided with an undercoat layer using a wire bar # 5, and a drying zone set at 100 ° C. having a length of 15 m is transported at a speed of 15 m / min. Passed at speed. After the application, a heat treatment was further performed at 60 ° C. for 24 hours. The application amount of the hydrophilic layer was 2.0 g / m ² .

(Coating of hydrophilic layer coating solution)
An aqueous dispersion having a solid content of 30% in which the following (a), (b) and (c) are mixed is prepared in advance.

(A) Colloidal silica (Snowtex S, solid content 30%; manufactured by Nissan Chemical Industries)
17.34 parts by mass (b) Colloidal silica (Snowtex PS-M, solid content 20%; manufactured by Nissan Chemical Industries, Ltd.) 38.89 parts by mass (c) Aluminosilicate particles (AMT silica 08, particle size 0.6 μm; (Made by Mizusawa Chemical Industry Co., Ltd.) 4.50 parts by mass The following materials are mixed in an aqueous dispersion containing about 30% solids containing (a), (b) and (c) described above, and dispersed for 1 hour with a homogenizer Then, a hydrophilic layer coating solution was prepared.

4% aqueous solution of sodium salt of carboxymethyl cellulose (manufactured by Kanto Chemical Co., Inc.)
5.00 parts by mass Complex oxide of Fe, Mn, Cu (MF black 4500, 40% aqueous dispersion; manufactured by Dainichi Seika Kogyo Co., Ltd.) 4.50 parts by mass A 5% aqueous solution of montmorillonite (Bengel 31; Toyoshun Yoko) 8.00 parts by mass A 1% aqueous solution of a silicon-based surfactant (FZ2161; manufactured by Nihon Unicar)
2.27 parts by mass Na ₃ PO ₄ (manufactured by Kanto Chemical Co.) 10% aqueous solution 1.00 parts by mass Pure water 18.69 parts by mass <Coating of image forming layer>
The image forming layer coating liquid 1 having the following composition is applied onto the hydrophilic layer formed as described above using a wire bar # 5, and a drying zone set at 60 ° C. having a length of 15 m is transported at a speed of 15 m / min. Passing through, an image forming layer was formed. The application amount of the image forming layer was 0.5 g / m ² .

  After coating the image forming layer, a heat treatment was further performed at 50 ° C. for 24 hours to obtain a lithographic printing plate material.

(Image forming layer coating solution 1)
Carnauba wax particle aqueous dispersion (Hi-Disper A-118, average particle size 0.5 μm, solid content 40%; manufactured by Gifu Shellac Manufacturing Co., Ltd.) 7.50 parts by mass Trehalose (Treha; Hayashibara Corporation) 2.00 masses 90.50 parts by mass of pure water <Evaluation of attachment of lithographic printing plate material to printing machine cylinder>
(Installation method 1)
1. Using the printing machine shown in FIG. 1, hold the leading edge of the above-described lithographic printing plate material with the original clamps 201 and 201 ′, wind it around the cylinders 2 and 2 ′, and fix the trailing edge of the lithographic printing plate with the clamp. did. The value of the surface specific resistance of the lithographic printing plate material at this time was 8.0 × 10 ⁸ Ω / cm ² .

Subsequently, the cylinders 2 and 2 'were nipped between the lithographic printing plate materials by rollers 1 and 1' coated with polystyrene having a surface specific resistance of 3.2 × 10 ¹⁸ Ω / cm ² , and the cylinder was rotated twice. . The surface specific resistance of the lithographic printing plate material after this operation was 4.3 × 10 ¹³ Ω / cm ² .

  When the lithographic printing plate wound around the cylinder through this process was peeled from the cylinder, it was confirmed that there was a resistance to peeling due to static electricity, and it was confirmed that it was firmly fixed to the cylinder.

(Installation method 2)
Using the printing machine shown in FIG. 1, the front end of the planographic printing plate material is clamped by the original clamps 201 and 201 ′, wound around the cylinder 105, and the gripping edge is clamped by the clamps 201 and 201 ′ after the planographic printing plate. The edge was fixed. The value of the surface specific resistance of the lithographic printing plate material at this time was 9.1 × 10 ⁷ Ω / cm ² . When this lithographic printing plate material was peeled from the cylinder, no resistance was felt, and it was confirmed that it was not sufficiently fixed to the cylinder.

(Plate making method and printing method)
Using the image recording device 5 '(semiconductor laser) to the planographic printing plate material fixed to the cylinder 2' of the first unit of the printing device (Fig. 1) by the installation method 1 or 2, the top 4 of the planographic printing plate material A registration mark image was exposed at the corner. The exposure conditions are an emission wavelength of 830 nm, a beam diameter of 32 μm (1 / e ² ), an output of 300 mW, and a plate surface energy intensity of 300 mJ / cm ² .

  A PS plate (aluminum substrate) on which a similar register mark image is formed is used for the cylinder 2 of the second unit, magenta ink is used for the cylinder of the first unit, and cyan ink is used for the cylinder of the second unit. Printing was performed at a speed of 8,000 sheets per hour using a 2% aqueous solution of Astro Mark 3 (manufactured by Nikken Chemical Laboratories).

  The misalignment of the square magenta and cyan registration mark images of the obtained printed matter was confirmed with 10, 100, 1000, 5000, and 10000 sheets.

  (Register mark deviation evaluation result; numerical value is μm)

  Regarding installation method 1, it was confirmed from the initial state that the registration accuracy was stable even when the number of printed sheets was advanced. On the other hand, with respect to the installation method 2, the registration marks on the right and left of the sky are greatly displaced at the initial stage of printing, and this seems to be because the planographic printing plate material is distorted in the cylinder. In addition, as the number of printed sheets progresses, the registration marks are greatly displaced on the top and bottom, which seems to be because they are not sufficiently fixed to the cylinder.

It is an example of the printing apparatus suitable for fixing the lithographic printing plate material of this invention to a cylinder.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1 'Charge roller 2, 2' Cylinder 3, 3 'Ink roller 4, 4' Blanket cylinder 5, 5 'Image recording device 6, 6' Ink fountain 7, 7 'Ink kneading roller 8, 8' Water supply device 9, 9 'Pressure cylinder 10 Paper feed mechanism 11 Paper feed cylinder 12 Paper discharge mechanism 201, 201' Clamp

Claims (6)

A method of installing a lithographic printing plate material, comprising: winding a lithographic printing plate material based on plastic around a cylinder of a printing machine; and fixing the lithographic printing plate material to the cylinder by charging. After the lithographic printing plate material is wound around a cylinder of a printing press, a roller-like member having a surface resistivity of 1 × 10 ¹⁰ Ω / cm ² or more and less than 1 × 10 ²⁰ Ω / cm ² is brought into contact with the lithographic printing plate material. The lithographic printing plate material installation method according to claim 1, wherein the lithographic printing plate material is charged by rotating the cylinder one or more times and fixed to the cylinder by charging. The lithographic printing plate material installation method according to claim 1 or 2, wherein the lithographic printing plate material is a heat mode recording material. A lithographic printing plate material based on plastic is fixed to a cylinder of a printing machine by the installation method of the lithographic printing plate material according to any one of claims 1 to 3, and then laser irradiation is performed on the cylinder. A plate making method comprising recording an image on the lithographic printing plate material. Supplying ink and dampening water to the lithographic printing plate material made by the plate making method according to claim 4 to form an image on the lithographic printing plate material, and transferring the image to a sheet-like substrate A printing method characterized by the above. In addition to the ink form roller and the water form roller, a roller having a surface specific resistance that can be nipped in a cylinder and has a surface specific resistance of 1 × 10 ¹⁰ Ω / cm ² or more and less than 1 × 10 ²⁰ Ω / cm ^2. A printing machine characterized by comprising.

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