JP2005081457A - Exposure device for press developing type printing plate material and manufacturing method for printing plate using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exposure device for a press developing type printing plate material which prevents the occurrence of degradation of a printing plate function by preventing foreign matter to be generated from adhering to a press developing type printing plate material in the exposure device using the press developing type printing plate material, and a manufacturing method for a printing plate. <P>SOLUTION: The exposure device for the press developing type printing plate, which has a sheet cutting means for feeding out the roll-shaped press developing type printing plate material and cutting it into a prescribed size, is characterized in that the sheet cutting means has a suction mechanism. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an on-machine development type printing plate material exposure apparatus having a function of removing foreign matter generated in an exposure apparatus, and a printing plate manufacturing method using the same.

  With the digitization of print data, CTP that records image data directly on a printing plate has become widespread. The printing plate material used for CTP includes a type using an aluminum base as in the case of a conventional PS plate and a flexible type in which a functional layer as a printing plate is provided on a film base. In recent years, in commercial printing, there is a tendency to reduce the number of copies of various types of printing, and there is a strong demand for high-quality and low-cost printing plate materials in the market. Conventional flexible type printing plate materials are, for example, those in which a silver salt diffusion transfer type photosensitive layer is provided on a film substrate as disclosed in JP-A-5-66564, or JP-A-8-507727. Either a hydrophilic layer or a lipophilic layer on a film substrate as disclosed in JP-A-6-186750, JP-A-6-199064, JP-A-7-314934, JP-A-10-58636, or JP-A-10-244773 The surface layer is laminated as a surface layer, and the surface layer is ablated by laser exposure to form a printing plate or a hydrophilic layer and a heat layer on a film substrate as disclosed in JP-A-2001-96710. A meltable image forming layer is provided, and the image forming layer is melt-fixed on the hydrophilic layer by heating the hydrophilic layer or the image forming layer in an image-like manner by laser exposure. It is below.

  The silver salt diffusion transfer system is not suitable for high-quality printing because it requires wet development and drying processes after exposure, and dimensional accuracy in the image forming process cannot be obtained sufficiently. The ablation method does not require development processing, but the dot shape tends to become unstable because an image is formed by ablation of the surface layer. Further, contamination of the material surface and the inside of the exposure apparatus due to the ablated surface layer scattering may occur. A method of converting a laser beam into heat and forming a heat-melted image on a hydrophilic layer provides a sharp dot shape and is suitable for high-definition image formation. In this method, the printing plate after image writing is printed with an offset printing machine, and only the image forming layer in the non-image area is swollen and dissolved with dampening water on the printing paper (damaged paper) at the initial printing stage. Some of them can be transferred and removed and developed on a printing press. In this case, since a development process after exposure is not required, quality stability and environmental suitability are excellent.

  In the case of CTP, in order to increase production efficiency, it is common to continuously and automatically operate a plate output device. A printing plate material using a film base is generally supplied into an output device in a roll form, automatically cut and conveyed to a predetermined size in the output device, fixed to an exposure member, and exposed (image) Writing) is done and used.

  In non-contact image writing such as laser exposure, foreign matter adhering to the printing plate material tends to be a defect on the output image. In the case of a printing plate material that is not subjected to a liquid development process, foreign matter adhering to the unexposed portion also causes image defects. Furthermore, when it adheres to the back side of the printing plate material, the flatness of the printing plate material at the time of exposure deteriorates, resulting in non-uniform exposure, which may cause image defects and printing unevenness. For this reason, in the on-press development type printing plate material as in the present invention, it is necessary to manage the foreign matter more strictly than the conventional printing plate material.

  The main factors for foreign matter adhering to the printing plate material are as follows: 1) Foreign matter adhering in the production process of the printing plate material is brought into the exposure apparatus and attached; 2) Adhered when the printing plate material is loaded into the exposure apparatus; 3) The chip | tip of the printing plate material generated when cutting in an exposure apparatus adheres.

  In particular, in the on-press development type printing plate material in which the hydrophilic layer and the heat-sensitive image forming layer are provided on the plastic film preferably used in the present invention, since the elastic modulus of the hydrophilic layer is small, chips are generated from the material during cutting. In some cases, the chips may adhere to the on-press development type printing plate material.

  Measures have been taken so far to prevent foreign matter from adhering to the printing plate material. For example, in order to cut a roll-shaped recording material and prevent adhesion of generated chips, the printing plate material cut by an adhesive roller installed in the conveyance path during conveyance to the exposure apparatus after cutting A method for cleaning the surface, or a method for removing foreign matters by blowing and sucking air on the surface of a printing plate material set in an exposure apparatus is known (see, for example, Patent Document 1).

  The use of an adhesive roller as described in Patent Document 1 is effective for removing foreign substances adhering to a roll-shaped photosensitive material, but a hydrophilic layer and heat-sensitive image formation on a plastic film preferably used in the present invention. On-press development type printing plate materials with layers, the conveyance accuracy in the exposure device decreases due to the contact of the adhesive roller, resulting in misregistration during printing, lower on-press development speed, and halftone dot reproducibility. Or printing plate functions such as printing stains on unexposed areas, plastic development used on the adhesive roller, uneven development, and pressure fog due to pressure on the adhesive roller may occur. , Not enough measures.

  Also, the method of removing foreign matters by blowing and sucking air is not preferable because the suction device becomes large to remove fine dust once scattered and the entire exposure device becomes large.

In this situation, in the exposure apparatus using the on-press development type printing plate material, the generated foreign matter is prevented from adhering to the on-press development type printing plate material. On-press development type printing plate material exposure apparatus (hereinafter also simply referred to as an exposure apparatus) and printing plate that does not cause deterioration of point reproducibility, development unevenness or printing plate functions such as printing stains in unexposed areas Development of a manufacturing method is desired.
Japanese Patent No. 3284399

  The present invention has been made in view of the above situation, and an object of the present invention is to prevent foreign matter generated from adhering to the on-press development type printing plate material in an exposure apparatus using the on-press development type printing plate material. An object of the present invention is to provide an exposure apparatus and a printing plate manufacturing method in which the printing plate function does not deteriorate.

The above object of the present invention has been achieved by the following constitution.
(Claim 1)
An on-press development type printing plate material exposure apparatus having a cutting means for feeding a roll-form on-press development type printing plate material and cutting it to a predetermined size, wherein the cutting means has a suction mechanism. Exposure equipment for mold printing plate materials.
(Claim 2)
The exposure apparatus for on-press development type printing plate material according to claim 1, wherein the suction mechanism performs vacuum suction from the start of feeding of the on-roll development type printing plate material to the end of cutting.
(Claim 3)
The exposure apparatus for on-press development type printing plate material according to claim 1 or 2, wherein the cutting means has an upper blade and a lower blade.
(Claim 4)
The on-machine development according to any one of claims 1 to 3, wherein the suction mechanism is a first suction means provided on an upper blade and a second suction means provided on a lower blade. Exposure equipment for mold printing plate materials.
(Claim 5)
The on-roll development type printing plate material is fed out and cut into a predetermined size, and the cut sheet-like on-machine development type printing plate material is fixed on an exposure member, subjected to laser exposure, and the laser-exposed sheet In the on-machine development type printing plate material exposure apparatus for discharging the on-machine development type printing plate material,
The machine is characterized in that the interior is maintained at 20 to 250 Pa higher than the atmospheric pressure when at least the roll-form on-press development printing plate material and the sheet-form on-machine development printing plate material are moving. Exposure device for upper development type printing plate material.
(Claim 6)
An exposure apparatus using an on-press development printing plate material having a hydrophilic layer and a heat-sensitive image forming layer in this order on a plastic film, and containing at least one layer a photothermal conversion material that converts near infrared rays into heat. 5. A printing plate production method for producing a printing plate by exposure by printing, wherein the exposure apparatus is the on-press development type printing plate material exposure apparatus according to any one of claims 1 to 4. Plate making method.
(Claim 7)
The printing plate according to claim 6, wherein the on-press development type printing plate material is a roll-type on-press development type printing plate material wound around a winding shaft so that the image forming layer side is an outer surface. Method.

  Exposure for on-press development type printing plate material that prevents adhesion of foreign matter to the on-press development type printing plate material and prevents deterioration of the printing plate function in an exposure apparatus that uses on-press development type printing plate material An apparatus and a method for producing a printing plate can be provided, and the quality of the printing plate can be improved.

  Embodiments according to the present invention will be described with reference to FIGS. 1 to 3. Of course, this figure shows an example of the present invention, and the present invention is not limited to this figure.

  FIG. 1 is a schematic view of a roll-on-machine development type printing plate material. FIG. 1A is a schematic perspective view of a roll-on-machine development type printing plate material. FIG. 1B is a schematic cross-sectional view taken along the line AA ′ of FIG.

  In the figure, reference numeral 1 denotes a roll-form on-press development type printing plate material. The roll-form on-machine development type printing plate material 1 is formed by winding a wide strip printing plate material cut to a predetermined width around a hollow cylindrical winding core 101 having a prescribed length and inner and outer diameters so that the image forming layer 106 side is the outer surface. It is made by installing. The roll-form on-press development type printing plate material shown in the figure is stored in the roll-form on-press development type printing plate material magazine (not shown) with the leading end 102 being put out. Then, a roll-form on-machine development type printing plate material magazine is mounted on the exposure apparatus, the tip is sandwiched and pulled out for a predetermined length, and cut in the exposure apparatus to obtain a sheet-form on-machine development type printing plate material. It is sent to the exposure unit and used.

  Reference numerals 103a and 103b denote flange members which have a diameter larger than the outer winding diameter of the roll-type on-machine development type printing plate material 1 and are attached to both ends of the hollow cylindrical winding core 101. 103a1 indicates an end side of the flange member 103a, and 103b1 indicates an end side of the flange member 103b. Reference numerals 103a2 and 13b2 denote outer surfaces of the flange members 103a2 and 13b2.

  Reference numeral 104 denotes a plastic film as a substrate, 105 denotes a hydrophilic layer provided on the plastic film 104, and 106 denotes an image forming layer provided on the hydrophilic layer 105. At least one of the hydrophilic layer 105 and the image forming layer 106 has a function of converting laser light into heat. Reference numeral 107 denotes a back coat layer. The back coat layer can be provided as necessary. Further, an antistatic layer may be provided on the image forming layer 106.

  The total thickness of the on-press development type printing plate material according to the present invention is preferably 150 to 300 [mu] m and the stiffness is 50 to 500 g. By setting the thickness and stiffness of the on-press development type printing plate material within the above ranges, characteristics preferable as an on-press development type printing plate material can be obtained from the viewpoints of printability and handleability.

  When the total thickness is less than 150 μm, depending on the type of substrate, the mechanical strength as a printing plate becomes insufficient, and printing durability and dimensional accuracy may deteriorate. When the thickness exceeds 300 μm, depending on the type of substrate, the rigidity of the printing plate becomes high, the positional accuracy during exposure becomes poor, and good print quality may not be obtained.

  When the stiffness is less than 50 g, the handleability as a printing plate is deteriorated, and the mounting accuracy to the printing press may not be obtained. When the stiffness exceeds 500 g, the handleability as a printing plate is deteriorated, and the mounting accuracy to the printing press may not be obtained.

  Stiffness is measured using Stiffness Tester UT-100-230 (manufactured by Toyo Seiki Seisakusho Co., Ltd.) as a measuring instrument, with a sample size of 10 cm x 8 cm (effective area 8 cm x 8 cm), a deflection angle of 10 degrees, and a pushing amount of 1 mm. It is the value.

  The thickness of the hydrophilic layer is preferably 0.5 to 10 μm. When the thickness is less than 0.5 μm, depending on the type of the hydrophilic layer, the film strength may be insufficient and the printing durability may be deteriorated. When the thickness exceeds 10 μm, the ink tends to adhere and print stains may occur in the non-image area.

  The image forming layer is preferably 0.2 to 5 μm. If it is less than 0.2 μm, the printing durability may be deteriorated. When the thickness exceeds 5 μm, the edge portion may deteriorate and the resolution may decrease depending on the type of the image forming layer.

  It is preferable to provide an antistatic layer on the side of the substrate on which the hydrophilic layer is provided, on the opposite side, or on both sides. In the case where the antistatic layer is provided between the base material and the hydrophilic layer, it also contributes to an improvement in adhesion with the hydrophilic layer. An intermediate hydrophilic layer can also be provided between the substrate and the hydrophilic layer. A back coat layer can also be provided on the back surface of the substrate. The details of the on-roll development type printing plate material of the present invention will be described later.

FIG. 2 is a schematic overall configuration diagram of the exposure apparatus.
In the figure, reference numeral 2 denotes an exposure apparatus. The exposure apparatus 2 includes an on-press development type printing plate material supply unit 3, a cutting unit 4, a transport unit 5, an exposure unit 6, a discharge unit 7, a pressure adjustment unit 8, and a main body 9. . Inside the main body 9, a partition wall 901 is provided between the on-press developing type printing plate material supply unit 3 and the cutting unit 4, in which a passage for the on-press developing type printing plate material 1 a is opened. It is preferable to provide a partition wall 902 in which a passage for the sheet-like on-press development type printing plate material 1b is opened between the unit 6 and the part 6. The inside of the main body 9 is divided into a first block having an on-press development type printing plate material supply unit 3, a second block having a cutting unit 4, and a third block having a transport unit 5 and an exposure unit 6 by a partition wall. Is possible.

  The on-press development type printing plate material supply unit 3 includes a cartridge 301 for storing the flange member of the on-roll development type printing plate material 1 on a rotatable roll guide 302, and the on-press development type printing from the cartridge 301. It has a pair of rollers 303 that draws the plate material 1a to a predetermined length.

  The cutting unit 4 has an upper blade 401 and a lower blade 402 for cutting a belt-like on-machine development type printing plate material 1a drawn to a predetermined length to form a sheet-like on-machine development type printing plate material 1b. doing. Reference numeral 405 denotes a suction tube 405 of an upper blade suction mechanism (first suction means) (see FIG. 3). Details of the cutting unit 4 will be described with reference to FIG.

  The conveyance unit 5 includes a conveyance roll 501 that conveys the sheet-like on-press development printing plate material 1b cut by the cutting unit 4 to the exposure unit.

  The exposure unit 6 fixes the sheet-form on-press development type printing plate material 1b sent from the transport unit 5 to the exposure drum 601 with the image forming layer 106 (see FIG. 1) facing upward, and performs exposure writing by laser light. Means 602, a peeling claw 603 for peeling off the sheet-like on-press development printing plate material 1c that has been subjected to image exposure by laser light from the exposure drum 601, and a sheet-like on-press development printing plate that has been peeled off after image exposure And a conveying roller 604 for discharging the material 1c.

  The discharge unit 7 includes a container 701 that receives the sheet-form on-press development type printing plate material 1c after the image exposure discharged from the exposure unit 6 is completed.

  The pressure adjusting unit 8 is configured to make the inside of the exposure apparatus 2 have a positive pressure with respect to the external pressure, and an air supply pipe 802 for supplying the dust removed through the filter 801 with a compressor or the like, and an exhaust pipe for adjusting the pressure. 803. The position where the pressure adjusting unit 8 is provided is preferably a third block having the transport unit 5 and the exposure unit 6. By adjusting the air supply amount and the exhaust amount, the inside of the exposure apparatus 2 can be made positive with respect to the external pressure.

  The pressure inside the exposure apparatus 2 is kept 20 to 250 Pa higher than the external pressure, and more preferably 30 to 150 Pa. When the pressure is less than 20 Pa, it is not preferable because a sufficient effect for removing fine foreign matters generated at the cutting portion cannot be obtained. When the pressure exceeds 250 Pa, the transportability of the belt-like on-press development type printing plate material 1a and the sheet-like on-press development type printing plate material 1c is affected, and positioning is not preferable.

  The period during which the inside of the exposure apparatus 2 is maintained at 20 to 250 Pa higher than the external pressure is preferably at least from the time when the on-press development type printing plate material is fed out from the cartridge, cut, and after image exposure is completed and discharged. .

  The following effects can be obtained by keeping the inside of the exposure apparatus 2 20 to 250 Pa higher than the external pressure. 1) Since foreign matter can be prevented from entering from the outside, it is possible to remove exposure defects (foreign matter spot failure) accompanying foreign matter adhesion. 2) Since foreign matter generated inside the exposure apparatus 2 is not brought into the exposure section, it is possible to prevent foreign matter from adhering to the sheet-form on-machine development printing plate material on the exposure drum.

  FIG. 3 is an enlarged schematic view of the cutting section shown in FIG. 3A is an enlarged schematic perspective view of the cutting portion shown in FIG. FIG. 3B is an enlarged schematic cross-sectional view along AA ′ of FIG.

  In the figure, reference numeral 403 denotes an attachment shaft of the upper blade 401, which is connected to a driving source (illustrated) and is rotatable (in the direction of the arrow in the figure). The upper blade 401 moves along the lower blade 402 while rotating (in the direction of the arrow in the figure) to cut the belt-like on-machine development printing plate material 1a into a sheet-like on-machine development printing plate material 1b. Is possible. Reference numeral 404 denotes an upper blade suction mechanism (first suction means) provided on the upper blade 401, and includes a hood 404a and a suction pipe 405 connected to a suction pump (not shown) for sucking the inside of the hood 404a. ing. By sucking the inside of the hood 404a, fine chips wound up by the upper blade 401 at the time of cutting can be removed outside the apparatus without being scattered inside the apparatus, and the sheet-like on-machine development type printing plate material 1b is obtained. This is an effective means for preventing the adhesion of dust. In the case of this figure, the upper blade suction mechanism (first suction means) shows a method of sucking the periphery of the upper blade, but a method of locally sucking the front and rear of the cutting point between the upper blade and the lower blade. It does not matter.

  Reference numeral 406 denotes a holder to which the lower blade 402 is attached, and has a groove portion 406b provided in the base 406a. The lower blade 402 is attached to the inside of the groove portion 406b, and a lower blade suction mechanism (second suction means) provided on the lower blade 402 is provided on the bottom portion 406c from the inner side to which the lower blade 402 of the groove portion 406b is attached. A suction hole 406d is provided. Reference numeral 406e denotes a suction pipe connected to the suction hole 406d for sucking the inside of the groove 406b, and the suction pipe 406e is connected to a suction pump (not shown). By sucking the groove portion 406b, fine chips generated at the time of cutting and accumulated inside the groove portion 406b can be removed outside the device without being scattered inside the device, and the sheet-like on-press development type printing plate material 1b is obtained. This is an effective means for preventing the adhesion of dust.

  The suction mechanism of the cutting part according to the present invention includes an upper blade suction mechanism (first suction means) provided on the upper blade and a lower blade suction mechanism (second suction means) provided on the lower blade. ing. The period during which the suction mechanism of the cutting unit is operated is preferably at least until the on-press development type printing plate material is fed out from the cartridge and cut. For the suction of the cutting part according to the present invention, either the upper blade suction mechanism (first suction means) or the lower blade suction mechanism (second suction means) may be operated at the same time during cutting. Alternatively, it can be appropriately selected depending on the type of the belt-like on-press development type printing plate material.

  The suction force by the suction mechanism may be set so as to optimize the foreign matter removal capability and the conveyance stability of the on-press development type printing plate material. In general, when the frequency of occurrence of foreign matter is high or the stiffness of the on-press development type printing plate material is large, it is preferable to set the suction force relatively high. For example, if the suction force of the upper blade suction mechanism (first suction means) is too strong than the stiffness of the on-press development type printing plate material, it is not preferable because the on-press development type printing plate material rises and the cutting position becomes unstable. On the contrary, when the suction force is weaker than the stiffness of the on-press development type printing plate material, the cutting position of the on-press development type printing plate material is stable, but chips generated at the time of cutting are scattered in the exposure apparatus, It adheres to the on-press development type printing plate material and causes failure.

  As shown in FIGS. 2 and 3, the on-press development type printing plate material exposure apparatus of the present invention 1) at least the on-press development type printing plate material is fed out from the cartridge, cut, and the image exposure is completed and discharged. Until it is done, the inside of the on-press developing type printing plate material exposure apparatus is kept at 20 to 250 Pa higher than the external pressure. 2) At least until the on-press developing type printing plate material is fed out from the cartridge and cut. By operating the suction mechanism of the cutting section, the adhesion of the generated foreign matter to the on-press development type printing plate material in the on-press development type printing plate material exposure device is prevented. It has become possible to produce a printing plate that does not cause a reduction in development speed, a reduction in halftone dot reproducibility, a development unevenness, or a printing plate function such as printing stains in unexposed areas. In the present invention, there is an effect even if the inside of the on-press development type printing plate material exposure apparatus is kept 20 to 250 Pa higher than the external pressure, but at the same time, the effect is further improved by operating the suction mechanism of the cutting section.

  The on-press development type printing plate material used in the present invention will be described below. The base material that can be used for the on-press development type printing plate material according to the present invention is a metal foil, paper, plastic film, or a composite thereof. A plastic film is particularly preferable from the viewpoint of handleability. The thickness of the substrate is preferably from 100 to 300 μm, particularly preferably from 150 to 250 μm, from the viewpoint of stable transportability in the printing plate preparation apparatus and ease of handling as a printing plate.

  Examples of the plastic film include polyethylene terephthalate, polyethylene naphthalate, polyimide, polyamide, polycarbonate, polysulfone, polyphenylene oxide, and cellulose esters. Particularly preferred are polyester films such as polyethylene terephthalate and polyethylene naphthalate.

It is preferable to provide an antistatic layer on the hydrophilic layer side, the opposite side, or both sides of the substrate. In the case where the antistatic layer is provided between the base material and the hydrophilic layer, it also contributes to an improvement in adhesion with the hydrophilic layer. As the antistatic layer, a polymer layer in which metal oxide fine particles and a matting agent are dispersed can be used. Examples of the material of the metal oxide particles used for the antistatic layer include SiO ₂ , ZnO, TiO ₂ , SnO ₂ , Al ₂ O ₃ , In ₂ O ₃ , MgO, BaO, MoO ₃ , V ₂ O _5, and these A composite oxide and / or a metal oxide further containing a different atom in these metal oxides can be given. These may be used alone or in combination. Preferred metal oxides are SiO ₂ , ZnO, SnO ₂ , Al ₂ O ₃ , TiO ₂ , In ₂ O ₃ , and MgO.
The thickness of the antistatic layer is preferably 0.01 to 1 μm.

  The surface of these plastic films may be subjected to corona discharge treatment, flame treatment, plasma treatment, ultraviolet irradiation treatment or the like in order to ensure adhesion with the hydrophilic layer. Further, the substrate surface can be mechanically roughened by sand blasting, brush polishing or the like. It is also a preferred embodiment to provide an undercoat layer made of latex having a hydrophilic functional group or a water-soluble resin.

  The hydrophilic layer of the on-press development type printing plate material of the present invention contains a hydrophilic matrix structure having a porous structure. As the material for forming the hydrophilic layer matrix, an organic hydrophilic matrix obtained by crosslinking or pseudo-crosslinking an organic hydrophilic polymer, or a sol comprising hydrolysis or condensation reaction of polyalkoxysilane, titanate, zirconate or aluminate. -An inorganic hydrophilic matrix layer, a metal oxide or the like obtained by gel conversion is preferably used. In particular, metal oxide fine particles are preferably included, and examples thereof include colloidal silica, alumina sol, titania sol, and other metal oxide sols. The form of the metal oxide fine particles may be spherical, needle-like, feather-like, or any other form. The average particle diameter is preferably 3 to 100 nm, and several metals having different average particle diameters are used. Oxide fine particles can also be used in combination. The surface of the particles may be surface treated.

  The metal oxide fine particles can be used as a binder by utilizing the film forming property. The decrease in hydrophilicity is less than when an organic binder is used, and it is suitable for use in a hydrophilic layer. Of these, colloidal silica is particularly preferred. Colloidal silica has the advantage of high film-forming properties even under relatively low temperature drying conditions, and can provide good strength. The colloidal silica that can be used in the present invention preferably includes necklace-shaped colloidal silica, which will be described later, and fine particle colloidal silica having an average particle size of 20 nm or less, and the colloidal silica preferably exhibits alkalinity as a colloidal solution.

  In the present invention, porous metal oxide particles having a particle size of less than 1 μm can be contained as a porous material having a hydrophilic layer matrix structure. As the porous metal oxide particles, the following porous silica, porous aluminosilicate particles, or zeolite particles can be preferably used.

  The porous silica particles are generally produced by a wet method or a dry method. In the wet method, the gel obtained by neutralizing the aqueous silicate solution can be obtained by drying and pulverizing, or by pulverizing the precipitate deposited by neutralization. In the dry method, silicon tetrachloride is burned together with hydrogen and oxygen to obtain silica. These particles can be controlled in their porosity and particle size by adjusting the production conditions. As the porous silica particles, those obtained from a wet gel are particularly preferable.

  The porosity of the particles is preferably 0.5 ml / g or more in terms of pore volume, more preferably 0.8 ml / g or more, and further preferably 1.0 to 2.5 ml / g. preferable. The pore volume is closely related to the water retention of the coating film. The larger the pore volume, the better the water retention, the less likely to get dirty during printing, and the greater the water volume latitude, but more than 2.5 ml / g When it becomes large, the particles themselves become very brittle, so that the durability of the coating film is lowered. Conversely, if the pore volume is less than 0.5 ml / g, the printing performance may be insufficient.

  Zeolite is a crystalline aluminosilicate and is a porous body having regular three-dimensional network voids having a pore diameter of 0.3 to 1 nm. The general formula combining natural and synthetic zeolite is expressed as follows:

(M1, (M2) _0.5 ) m (AlmSinO ₂ ) (m + n) · xH ₂ O
Here, M1 and M2 are exchangeable cations, and M1 is Li ⁺ , Na ⁺ , K ⁺ , Tl ⁺ , Me ₄ N + (TMA), Et ₄ N + (TEA), Pr ₄ N + (TPA), C ₇ H ₁₅ N ₂ +, C ₈ H ₁₆ N + and the like, and M2 is Ca ²⁺ , Mg ²⁺ , Ba ²⁺ , Sr ²⁺ , C ₈ H ₁₈ N ₂ ^{2+ and the} like. Further, n ≧ m, and the value of m / n, that is, the Al / Si ratio is 1 or less. The higher the Al / Si ratio, the greater the amount of exchangeable cations, and thus the higher the polarity and therefore the higher the hydrophilicity. A preferable Al / Si ratio is 0.4 to 1.0, and more preferably 0.8 to 1.0. x represents an integer.

The zeolite particles used in the present invention are preferably synthetic zeolite having a stable Al / Si ratio and a relatively sharp particle size distribution. For example, zeolite A: Na ₁₂ (Al ₁₂ Si ₁₂ O ₄₈ ). 27H ₂ O; Al / Si ratio 1.0, zeolite X: Na ₈₆ (Al ₈₆ Si ₁₀₆ O ₃₈₄ ) · 264H ₂ O; Al / Si ratio 0.811, zeolite Y: Na ₅₆ (Al ₅₆ Si ₁₃₆ O ₃₈₄ 250H ₂ O; Al / Si ratio 0.412 and the like.

  By containing highly hydrophilic porous particles having an Al / Si ratio of 0.4 to 1.0, the hydrophilicity of the hydrophilic layer itself is greatly improved, it is difficult to get dirty during printing, and the water latitude is widened. In addition, the dirt on the fingerprint marks is greatly improved. When the Al / Si ratio is less than 0.4, the hydrophilicity is insufficient, and the effect of improving the performance becomes small.

  In addition, the hydrophilic layer matrix structure of the on-press development type printing plate material of the present invention can contain layered clay mineral particles. Examples of the layered mineral particles include kaolinite, halloysite, talc, smectite (montmorillonite, beidellite, hectorite, sabonite, etc.), clay minerals such as vermiculite, mica (mica), chlorite, hydrotalcite, layered polysilicic acid. Examples thereof include salts (kanemite, macatite, ialite, magadiite, kenyaite, etc.). In particular, the higher the charge density of the unit layer (unit layer), the higher the polarity and the higher the hydrophilicity. The charge density is preferably 0.25 or more, more preferably 0.6 or more. Examples of the layered mineral having such a charge density include smectite (charge density 0.25 to 0.6; negative charge), vermiculite (charge density 0.6 to 0.9; negative charge) and the like. In particular, synthetic fluoromica is preferable because it can be obtained with stable quality such as particle size. Among the synthetic fluorine mica, those that are swellable are preferable, and those that are free swell are more preferable.

  Also used are intercalation compounds of the above-mentioned layered minerals (pillar crystals, etc.), those subjected to ion exchange treatment, and those subjected to surface treatment (silane coupling treatment, compounding treatment with organic binder, etc.) can do.

  As the size of the flat lamellar mineral particles, the average particle diameter (maximum length of the particles) is less than 1 μm in the state of being contained in the layer (including the case where the swelling process and the dispersion peeling process have been performed). The aspect ratio is preferably 50 or more. When the particle size is in the above range, the continuity and flexibility in the planar direction, which are the characteristics of the thin layered particles, are imparted to the coating film, and it is difficult for cracks to occur, and a tough coating film can be obtained in a dry state. Moreover, in the coating liquid containing many particulate matters, sedimentation of particulate matter can be suppressed by the thickening effect of the layered clay mineral. When the particle diameter is larger than the above range, the coating film may be non-uniform, and the strength may be locally reduced. On the other hand, when the aspect ratio is not more than the above range, the number of tabular grains with respect to the addition amount is reduced, the viscosity is insufficient, and the effect of suppressing sedimentation of the particulate matter is reduced.

  The content of the layered mineral particles is preferably 0.1 to 30% by mass, and more preferably 1 to 10% by mass based on the entire layer. In particular, swellable synthetic fluorinated mica and smectite are preferable because they are effective even when added in a small amount. The layered mineral particles may be added as a powder to the coating solution, but in order to obtain a good degree of dispersion even with a simple preparation method (no need for a dispersion step such as media dispersion), the layered mineral particles are used alone. It is preferable to prepare the gel swollen in water and add it to the coating solution.

A silicate aqueous solution can also be used as another additive material in the hydrophilic layer matrix of the present invention. Alkali metal silicates such as silicate Na, silicate K, and silicate Li are preferred, and the SiO ₂ / M ₂ O ratio is in a range where the pH of the entire coating solution does not exceed 13 when silicate is added. It is preferable to select such that the inorganic particles are not dissolved.

  Further, an inorganic polymer or an organic-inorganic hybrid polymer using a metal alkoxide by a so-called sol-gel method can also be used. The formation of an inorganic polymer or an organic-inorganic hybrid polymer by the sol-gel method is described in, for example, “Application of the sol-gel method” (Sakuo Sakuo / Agne Jofusha) or is described in this document. Known methods described in the cited documents can be used.

  Moreover, in this invention, you may contain water-soluble resin in a hydrophilic layer. Examples of the water-soluble resin include polysaccharides, polyethylene oxide, polypropylene oxide, polyvinyl alcohol, polyethylene glycol (PEG), polyvinyl ether, styrene-butadiene copolymer, conjugated diene polymer latex of methyl methacrylate-butadiene copolymer. Examples thereof include resins such as acrylic polymer latex, vinyl polymer latex, polyacrylamide, sodium polyacrylate, and polyvinyl pyrrolidone. As the water-soluble resin used in the present invention, it is preferable to use a polysaccharide.

  As polysaccharides, starches, celluloses, polyuronic acids, pullulans and the like can be used, but cellulose derivatives such as methyl cellulose salts, carboxymethyl cellulose salts, hydroxyethyl cellulose salts are particularly preferable, and sodium salts and ammonium salts of carboxymethyl cellulose are preferable. More preferred. This is because an effect of forming the surface shape of the hydrophilic layer in a preferable state can be obtained by including the polysaccharide in the hydrophilic layer.

  The surface of the hydrophilic layer preferably has a concavo-convex structure with a pitch of 0.1 to 20 μm like the aluminum grain of the PS plate, and this concavo-convex improves water retention and image area retention. Such a concavo-convex structure can be formed by adding an appropriate amount of a filler having an appropriate particle size to the hydrophilic layer matrix. However, the above-mentioned alkaline colloidal silica and the above-mentioned water-soluble solution are added to the hydrophilic layer coating solution. It is preferable that a structure having better printability can be obtained by forming a phase separation when the hydrophilic polysaccharide is applied and dried.

  The shape of the concavo-convex structure (such as pitch and surface roughness) is determined by the type and amount of alkaline colloidal silica, the type and amount of water-soluble polysaccharides, the type and amount of other additives, the solid content concentration of the coating solution, and the wetness. It is possible to appropriately control the film thickness, drying conditions, and the like.

  As the inorganic particles that can be used in the present invention, for example, known metal oxide particles such as silica, alumina, titania, zirconia, etc. can be used, but in order to suppress sedimentation in the coating solution, it is porous. Preferably, metal oxide particles are used. As the porous metal oxide particles, the aforementioned porous silica particles and porous aluminosilicate particles can be preferably used.

  Examples of the particles coated with an inorganic material include particles in which organic particles such as polymethyl methacrylate and polystyrene are used as a core material, and the particles are coated with inorganic particles having a particle diameter smaller than that of the core material particles. The particle size of the inorganic particles is preferably about 1/10 to 1/100 of the core particles. As the inorganic particles, known metal oxide particles such as silica, alumina, titania, zirconia, etc. can be used. As the coating method, various known methods can be used, but the core material particles and the coating material particles are collided at high speed in the air like a hybridizer to cause the coating material particles to bite into the surface of the core material particles. A dry coating method of fixing and coating can be preferably used.

  Moreover, the particle | grains which carried out the metal plating of the core material of an organic particle can also be used. Examples of such particles include “Micropearl AU” manufactured by Sekisui Chemical Co., Ltd., in which resin particles are plated with gold.

  The particle size is 1 μm or more and it is necessary to satisfy the relationship of the formula (1) defined in the present invention with respect to the average film thickness of the hydrophilic matrix structure, but 1 to 10 μm is preferable, and 1.5 to 8 micrometers is more preferable and 2 micrometers-6 micrometers are still more preferable. When the particle diameter exceeds 10 μm, there is a concern that the resolution of image formation is reduced and the blanket stain is deteriorated. In the present invention, the amount of particles having a particle diameter of 1 μm or more is appropriately adjusted so as to satisfy the surface morphology parameters according to the present invention, but is preferably 1 to 50% by mass of the entire hydrophilic layer. 5 to 40% by mass is more preferable. The hydrophilic layer as a whole preferably has a low content ratio of materials containing carbon such as organic resin and carbon black in order to improve hydrophilicity, and the total of these materials is preferably less than 9% by mass. More preferably, it is less than 5 mass%.

  An intermediate hydrophilic layer can be provided between the substrate and the hydrophilic layer. As the material used for the intermediate hydrophilic layer, the same material as the hydrophilic layer can be used. However, the intermediate hydrophilic layer is less advantageous in that it is porous, and more nonporous is preferable from the viewpoint of coating strength. The content of the porous material forming the hydrophilic matrix structure is preferably less than the hydrophilic layer, and more preferably not contained.

  The addition amount of the particles having a particle size of 1 μm or more used in the intermediate hydrophilic layer is appropriately adjusted so as to satisfy the surface morphology parameter according to the present invention, but is 1 to 50% by mass of the entire intermediate hydrophilic layer. It is preferable that it is 5 to 40% by mass.

  Similarly to the hydrophilic layer, the intermediate hydrophilic layer as a whole is preferably low in content ratio of materials containing carbon such as organic resin and carbon black in order to improve hydrophilicity, and the total of these materials is 9 mass. % Is preferable, and it is more preferable that it is less than 5% by mass.

  The hydrophilic layer, the intermediate hydrophilic layer, and other layers provided in the present invention can contain a photothermal conversion material. As the photothermal conversion material, it is preferable to use an infrared absorbing dye, an inorganic / organic pigment, a metal, or a metal oxide, and specific examples thereof include the following materials.

  Infrared absorbing dyes include cyanine dyes, croconium dyes, polymethine dyes, azurenium dyes, squalium dyes, thiopyrylium dyes, naphthoquinone dyes, anthraquinone dyes and other organic compounds, phthalocyanine dyes, naphthalocyanine dyes, Examples include azo-based, thioamide-based, dithiol-based, and indoaniline-based organometallic complexes. Specifically, JP-A-63-139191, JP-A-64-33547, JP-A-1-160683, JP-A-1-280750, JP-A-1-293342, JP-A-2-2074, Kaihei 3-26593, JP-A-3-30991, JP-A-3-34891, JP-A-3-36093, JP-A-3-36094, JP-A-3-36095, JP-A-3-42281, JP-A-3-42281 Examples thereof include compounds described in JP-A-3-97589, JP-A-3-103476, and the like. These can be used alone or in combination of two or more.

  Examples of the pigment include carbon, graphite, metal, metal oxide and the like. As carbon, it is particularly preferable to use furnace black or acetylene black. The particle size (d50) is preferably 100 nm or less, and more preferably 50 nm or less.

  As the graphite, fine particles having a particle size of 0.5 μm or less, preferably 100 nm or less, more preferably 50 nm or less can be used.

  As the metal, any metal can be used as long as the particle diameter is 0.5 μm or less, preferably 100 nm or less, more preferably 50 nm or less. The shape may be any shape such as a spherical shape, a piece shape, or a needle shape. Colloidal metal fine particles (Ag, Au, etc.) are particularly preferable.

As the metal oxide, a material that is black in the visible light region, or a material that has conductivity or is a semiconductor can be used. Examples of the former include black iron oxide (Fe ₃ O ₄ ) and black composite metal oxides containing two or more of the aforementioned metals. Examples of the latter include Sb-doped SnO ₂ (ATO), Sn-added In ₂ O ₃ (ITO), TiO ₂ , TiO ₂ reduced TiO (titanium oxynitride, generally titanium black) Etc. These metal oxides are coated with a core material (BaSO ₄ , TiO ₂ , 9Al ₂ O ₃ .2B ₂ O, K ₂ O.nTiO _2, etc.). Conversely, the surface of the metal oxide particles is hydrophilic. Those coated with a compound can also be used. These particle sizes are 0.5 μm or less, preferably 100 nm or less, and more preferably 50 nm or less.

Among these photothermal conversion materials, black iron oxide (Fe ₃ O ₄ ), which is a metal oxide, and a black composite metal oxide containing two or more metals are more preferable materials. If the specific example of complex oxide is given, it will be a complex metal oxide which consists of two or more sorts of metals chosen from Al, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sb, and Ba. These are disclosed by methods disclosed in JP-A-8-27393, JP-A-9-25126, JP-A-9-237570, JP-A-9-241529, JP-A-10-231441, and the like. Can be manufactured.

  The composite metal oxide is particularly preferably a Cu-Cr-Mn-based or Cu-Fe-Mn-based composite metal oxide. In the case of a Cu—Cr—Mn system, it is preferable to perform the treatment disclosed in JP-A-8-27393 in order to reduce the elution of hexavalent chromium. These composite metal oxides are colored with respect to the amount added, that is, they have good photothermal conversion efficiency.

  These metal oxide photothermal conversion materials preferably have an average primary particle diameter of 1 μm or less, and more preferably have an average primary particle diameter in the range of 0.01 to 0.5 μm. When the average primary particle diameter is 1 μm or less, the photothermal conversion ability with respect to the addition amount becomes better, and when the average primary particle diameter is within the range of 0.01 to 0.5 μm, the photothermal conversion ability with respect to the addition amount is better. It becomes. However, the photothermal conversion ability with respect to the addition amount is greatly affected by the degree of dispersion of the particles, and the better the dispersion, the better. Therefore, these metal oxide light-to-heat conversion materials are preferably dispersed by a known method before being added to the layer coating solution to prepare a dispersion (paste). When the average primary particle size is less than 0.01, it is not preferable because dispersion becomes difficult. A dispersing agent can be appropriately used for the dispersion. The addition amount of the dispersant is preferably 0.01 to 5% by mass, and more preferably 0.1 to 2% by mass with respect to the metal oxide particles.

  As addition amount of these metal oxides, it is 0.1-60 mass% with respect to a hydrophilic layer or a lower layer, 3-60 mass% is preferable, and 3-45 mass% is more preferable. The addition amount of the photothermal conversion material may be different between the hydrophilic layer and the intermediate hydrophilic layer.

  The image forming functional layer of the on-roll development-type printing plate material according to the present invention contains heat-meltable and / or heat-fusible fine particles, and can contain the following materials. The heat-meltable fine particles are fine particles formed of a material that has a low viscosity when melted, and is generally classified as a wax, among thermoplastic materials. The physical properties are preferably a softening point of 40 ° C. or higher and 120 ° C. or lower, a melting point of 60 ° C. or higher and 100 ° C. or lower, more preferably a softening point of 40 ° C. or higher and 100 ° C. or lower, and a melting point of 60 ° C. or higher and 120 ° C. or lower. When the melting point is less than 60 ° C., storage stability is a problem, and when the melting point is higher than 300 ° C., ink deposition sensitivity is lowered.

  Examples of usable materials include paraffin wax, polyolefin, polyethylene wax, microcrystalline wax, carnauba wax, candelilla wax, montan wax, and fatty acid wax. These have a molecular weight of about 800 to 10,000, and in order to facilitate emulsification, these waxes can be oxidized to introduce polar groups such as hydroxyl groups, ester groups, carboxyl groups, aldehyde groups, and peroxide groups. Furthermore, in order to lower the softening point and improve the workability, these waxes include, for example, stearamide, linolenamide, laurylamide, myristamide, hardened bovine fatty acid amide, palmitoamide, oleic acid amide, rice sugar fatty acid amide, It is also possible to add coconut fatty acid amides or methylolated products of these fatty acid amides, methylene bisstellaramide, ethylene bisstellaramide and the like. Coumarone-indene resin, rosin-modified phenol resin, terpene-modified phenol resin, xylene resin, ketone resin, acrylic resin, ionomer, and copolymers of these resins can also be used.

  Among these, it is preferable to contain any one of polyethylene wax, microcrystalline wax, carnauba wax, fatty acid ester, and fatty acid. Since these materials have a relatively low melting point and a low melt viscosity, high-sensitivity image formation can be performed. Further, since these materials have lubricity, damage when a shearing force is applied to the surface of the on-press development type printing plate material is reduced, and resistance to printing stains due to scratches or the like is improved.

  The heat-meltable fine particles are preferably dispersible in water, and the average particle size is preferably 0.01 to 10 μm, more preferably 0.1 to 3 μm. When the average particle size is smaller than 0.01 μm, when the coating liquid for the layer containing the heat-meltable fine particles is applied onto the porous hydrophilic layer described later, the heat-meltable fine particles are not removed from the pores of the hydrophilic layer. It becomes easy to enter inside or into the gaps between fine irregularities on the surface of the hydrophilic layer, and the on-press development becomes insufficient, which may cause scumming. When the average particle size of the heat-meltable fine particles is larger than 10 μm, the resolution is lowered.

  Moreover, the composition of the inside and the surface layer of the heat-meltable fine particles may be continuously changed, or may be coated with a different material. As a coating method, a known microcapsule formation method, a sol-gel method, or the like can be used.

  As content of the heat-meltable microparticles | fine-particles in a structural layer, 1-90 mass% of the whole layer is preferable, and 5-80 mass% is more preferable.

  Examples of the heat-fusible fine particles that can also be used in the present invention include thermoplastic hydrophobic polymer fine particles, and there is no specific upper limit to the softening temperature of the thermoplastic hydrophobic high-molecular polymer particles. Is preferably lower than the decomposition temperature of the polymer fine particles. Moreover, it is preferable that the weight average molecular weight (Mw) of a high molecular weight polymer is the range of 10,000-1,000,000.

  Specific examples of the polymer constituting the polymer particles include, for example, diene (co) polymers such as polypropylene, polybutadiene, polyisoprene and ethylene-butadiene copolymer, styrene-butadiene copolymer, Synthetic rubbers such as methyl methacrylate-butadiene copolymer, acrylonitrile-butadiene copolymer, polymethyl methacrylate, methyl methacrylate- (2-ethylhexyl acrylate) copolymer, methyl methacrylate-methacrylic acid copolymer, methyl acrylate- ( N-methylolacrylamide) copolymer, (meth) acrylic acid ester such as polyacrylonitrile, (meth) acrylic acid (co) polymer, polyvinyl acetate, vinyl acetate-vinyl propionate copolymer, vinyl acetate-ethylene copolymer Vinyl etc. of polymers Ester (co) polymer, vinyl acetate - (2-ethylhexyl acrylate) copolymers, polyvinyl chloride, polyvinylidene chloride, polystyrene and copolymers thereof. Of these, (meth) acrylic acid esters, (meth) acrylic acid (co) polymers, vinyl ester (co) polymers, polystyrene, and synthetic rubbers are preferably used.

  The polymer polymer fine particles may be composed of a polymer polymer polymerized by any known method such as an emulsion polymerization method, a suspension polymerization method, a solution polymerization method, and a gas phase polymerization method. As a method of microparticulating a polymer polymer polymerized by a solution polymerization method or a gas phase polymerization method, a method of spraying a solution in an organic solvent of the polymer polymer into an inert gas and drying to form particles, Examples thereof include a method in which a high molecular weight polymer is dissolved in a water-immiscible organic solvent, this solution is dispersed in water or an aqueous medium, and the organic solvent is distilled off to form fine particles. In any of the methods, the heat-meltable fine particles and the heat-fusible fine particles may be used as a dispersant or a stabilizer, for example, when polymerized or finely divided, such as sodium lauryl sulfate, sodium dodecylbenzenesulfonate, polyethylene. A surfactant such as glycol or a water-soluble resin such as polyvinyl alcohol may be used. Further, triethylamine, triethanolamine or the like may be contained.

  The thermoplastic fine particles are preferably dispersible in water, and the average particle diameter is preferably 0.01 to 10 μm, more preferably 0.1 to 3 μm. When the average particle size is smaller than 0.01 μm, when the coating liquid for the layer containing the heat-meltable fine particles is applied onto the porous hydrophilic layer described later, the heat-meltable fine particles are not removed from the pores of the hydrophilic layer. It becomes easy to enter inside or into the gaps between fine irregularities on the surface of the hydrophilic layer, and the on-press development becomes insufficient, which may cause scumming. When the average particle size of the heat-meltable fine particles is larger than 10 μm, the resolution is lowered.

  The thermoplastic fine particles may be continuously coated with different materials or the composition of the inside and the surface layer may be changed. As a coating method, a known microcapsule formation method, a sol-gel method, or the like can be used.

  As content of the thermoplastic fine particle in a structure layer, 1-90 mass% of the whole layer is preferable, and 5-80 mass% is further more preferable.

  The image-forming functional layer containing the heat-fusible and / or heat-fusible fine particles according to the present invention can further contain a water-soluble material. By including the water-soluble material, when the image forming functional layer in the unexposed area is removed using dampening water or ink on the printing press, the removability can be improved.

  As the water-soluble material, the water-soluble resins mentioned as materials that can be contained in the hydrophilic layer can also be used. However, as the image forming functional layer of the present invention, it is preferable to use saccharides, particularly oligosaccharides. Is preferred.

  Among oligosaccharides, trehalose is commercially available in a relatively high purity state at a low cost, and despite its high solubility in water, its hygroscopicity is very low, and on-press developability and The storage stability is very good.

  In addition, when oligosaccharide hydrate is melted by heat to remove water of hydration and then solidified (for a short time after solidification), it becomes an anhydrous crystal, but trehalose has a melting point of anhydride higher than that of hydrate. It is characteristic that it is higher than 100 ° C. This means that the exposed portion is melted by infrared exposure and immediately after re-solidification, the exposed portion is in a state of being difficult to melt at a high melting point, and is effective in causing image defects during exposure such as banding. In order to achieve the object of the present invention, trehalose is particularly preferable among oligosaccharides.

  As content of the oligosaccharide in a structure layer, 1-90 mass% of the whole layer is preferable, and 10-80 mass% is more preferable.

  A back coat layer may be formed on the back surface of the roll-shaped printing material according to the present invention in order to obtain desired smoothness and static friction coefficient. In addition to the binder component and the mat material, it is preferable to add a compound that imparts surface lubricity and conductivity to the back coat layer. Binders include gelatin, polyvinyl alcohol, methyl cellulose, nitrocellulose, acetyl cellulose, aromatic polyamide resin, silicone resin, epoxy resin, alkyd resin, phenol resin, melamine resin, fluorine resin, polyimide resin, urethane resin, acrylic resin, urethane Modified silicone resin, polyethylene resin, polypropylene resin, Teflon (R) resin, polyvinyl butyral resin, vinyl chloride resin, polyvinyl acetate, polycarbonate, organic boron compound, aromatic esters, fluorinated polyurethane, polyethersulfone, polyester resin, A general-purpose polymer such as a polyamide resin, a polystyrene resin, or a copolymer containing these monomers as main components can be used.

  The use of a crosslinkable binder as the binder is effective for preventing the mat material from falling off and improving the scratch resistance of the backcoat. It is also very effective for blocking during storage. This cross-linking means can be employed without any particular limitation on any one or combination of heat, actinic rays and pressure according to the characteristics of the cross-linking agent used. Depending on the case, in order to provide the adhesiveness to a base material, you may provide arbitrary easy-adhesion layers in the side which provides the backcoat layer of a base material.

  As the mat material preferably added to the back coat layer, organic or inorganic fine particles can be used. Examples of the organic fine particles include organic fine particles made of a resin such as a silicone resin, a fluororesin, an acrylic resin, a methacrylic resin, and a melamine resin. Among these, a silicone resin, an acrylic resin, and a methacrylic resin are preferable. Examples thereof include polymethyl methacrylate (PMMA), polystyrene resin, polyethylene resin, polypropylene resin, fine particles of other radical polymerization polymers, and fine particles of condensation polymers such as polyester and polycarbonate. Examples of the inorganic fine particles include inorganic fine particles such as silicon oxide, calcium carbonate, titanium dioxide, aluminum oxide, zinc oxide, barium sulfate, and zinc sulfate. Among these, titanium dioxide, calcium carbonate, and silicon oxide are preferable.

  The average particle size of the inorganic fine particles is preferably 0.5 to 10 μm, and more preferably 0.8 to 5 μm. When the average particle size is less than 0.5 μm, the back coat layer cannot be sufficiently roughened, and a long-time decompression is required to obtain uniform adhesion. If it exceeds 10 μm, the back coat layer is too rough and the smoother value becomes large, and stable adhesion to the fixing member cannot be ensured.

The back coat layer is preferably provided on the plastic film substrate in an amount of about 0.5 to 3 g / m ² . If it is less than 0.5 g / m ² , the coating property is unstable, and problems such as powdering off of the mat material are likely to occur. Also, if it is applied greatly exceeding 3 g / m ² , the particle size of a suitable mat material becomes very large, and embossing of the image receiving surface by the back coat layer occurs during storage, resulting in missing or uneven recording images. It becomes easy. When the matting agent is not added, the attached amount of the back coat layer is preferably 0.01 to 1.0 g / m ² .

  As content of the said microparticles | fine-particles, 0.5-80 mass% is preferable with respect to the total solid content mass of a backcoat layer, and 1-20 mass% is more preferable. When the content is less than 0.5% by mass, the back coat layer surface may not be sufficiently roughened. When the content exceeds 80% by mass, the back coat layer is too rough and smooth. The image value may increase and the image quality may deteriorate.

  For the purpose of adjusting the surface slipperiness, it is also preferable to add various surfactants, silicon oil, fluororesin, waxes and the like to the back coat layer.

  An antistatic agent can also be added to prevent on-machine development type printing plate material from being transported abnormally due to frictional charging in the transport path and from adhering foreign matter due to charging. As the antistatic agent, cationic surfactants, anionic surfactants, nonionic surfactants, polymer antistatic agents, conductive fine particles and the like can be used. Among these, fine particles of metal oxides such as carbon black, graphite, tin oxide, zinc oxide and titanium oxide, and conductive fine particles such as organic semiconductors are preferably used. In particular, it is preferable to use fine particles of carbon black and graphite, particularly metal oxide, because a stable antistatic ability can be obtained regardless of environmental influences such as temperature.

Examples of the material of the metal oxide fine particles include SiO ₂ , ZnO, TiO ₂ , SnO ₂ , Al ₂ O ₃ , In ₂ O ₃ , MgO, BaO, MoO ₃ , V ₂ O ₅ and composite oxides thereof, and Examples of the metal oxide further include a metal oxide containing a different atom. These may be used alone or in combination. Among these, preferable metal oxides are SiO ₂ , ZnO, SnO ₂ , Al ₂ O ₃ , TiO ₂ , In ₂ O ₃ , and MgO. As an example containing a small amount of hetero atoms, Al or In with respect to ZnO, Sb, Nb or halogen elements with respect to SnO ₂ , and hetero atoms such as Sn with respect to In ₂ O ₃ of 30 mol% or less, preferably 10 What doped the quantity below mol% can be mentioned.

  The metal oxide fine particles are preferably contained in the back coat layer in the range of 10 to 90% by mass. The average particle diameter of the metal oxide fine particles is preferably in the range of 0.001 to 0.5 μm. The average particle size here is a value including not only the primary particle size of the metal oxide fine particles but also the particle size of the higher order structure.

It is more preferable that the on-press development type printing plate material has a layer or a substrate having a surface specific resistance of 108 to 1012 Ω / m ^{2 at} a relative humidity of 80% or less. As the antistatic agent that can be used, various surfactants and conductive agents can be appropriately used so that the surface specific resistance of the layer at a relative humidity of 80% or less is 108 to 1012 Ω / m ² . In particular, it is preferable to design the layer so that the surface specific resistance is 10 ⁸ to 10 ¹² Ω / m ² by containing at least one of carbon black, carbon graphite, and metal oxide fine particles in the layer.

  When performing laser exposure at the time of image formation, in order to prevent the focus from deviating, it is preferable to perform reduced pressure adhesion in combination with a known method for fixing the plastic film substrate. The surface roughness (Rz) when a matting agent is added to a base material or back coat layer whose back surface is roughened for the purpose of preventing blocking or imparting good vacuum adhesion is 0.04 to 5.00 μm. The range of is preferable.

  The smooth star value on the back surface of the on-press development type printing plate material is preferably 0.06 MP or less, and more preferably in the range of 0.0003 MP to 0.06 MP. In the case of 0.0003 MP or less, the uniform adhesion to the fixing member is deteriorated or the time required for stable adhesion is increased. When it is larger than 0.06 MP, the fixing onto the fixing member is insufficient and stable image exposure cannot be performed.

  The coefficient of static friction between the back surface of the on-press development type printing plate material and the fixed member surface is preferably 0.2 to 0.6. Even in the case of 0.2 or less or 0.6 or more, the fixing position accuracy on the fixing member is lowered, which is not preferable.

  An example of the image forming method in the present invention will be given below. Image formation in the on-press development type printing plate material according to the present invention can be performed by heat, but it is particularly preferable to perform image formation by exposure with an infrared laser.

  More specifically, the exposure is preferably scanning exposure using a laser that emits light in the infrared and / or near-infrared region, that is, in the wavelength range of 700 to 1000 nm. A gas laser may be used as the laser, but it is particularly preferable to use a semiconductor laser that emits light in the near infrared region.

  In the present invention, as an apparatus suitable for scanning exposure, any apparatus can be used as long as it can form an image on the surface of an on-press development type printing plate material in accordance with an image signal from a computer using a semiconductor laser. It may be.

In general,
(1) A method of exposing the entire surface of the on-press development type printing plate material by performing two-dimensional scanning using one or a plurality of laser beams on the on-press development type printing plate material held by the flat plate-like holding mechanism. ,
(2) An on-press development type printing plate material held along a cylindrical surface inside a fixed cylindrical holding mechanism, and using one or more laser beams from the inside of the cylinder, the circumferential direction of the cylinder A method of exposing the entire surface of the on-press development type printing plate material by moving in the direction perpendicular to the circumferential direction (sub-scanning direction) while scanning in the (main scanning direction),
(3) A printing plate material held on the surface of a cylindrical drum that rotates about an axis as a rotating body is rotated in the circumferential direction (main scanning direction) by rotating the drum using one or a plurality of laser beams from the outside of the cylinder. ) And moving in the direction perpendicular to the circumferential direction (sub-scanning direction) to expose the entire on-press development type printing plate material.

In the present invention, the scanning exposure method described in the item (3) is particularly preferable, and the exposure method described in the item (3) is used particularly in an apparatus that performs exposure on a printing apparatus.
EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated concretely, this invention is not limited to these.

Example 1
(Production of polyethylene terephthalate (PET) base material)
Using terephthalic acid and ethylene glycol, PET of IV (inherent viscosity) = 0.66 (measured in phenol / tetrachloroethane = 6/4 (mass ratio) at 25 ° C.) was obtained according to a conventional method. This was pelletized, dried at 130 ° C. for 4 hours, melted at 300 ° C., and extruded from a T-die to produce an unstretched film. This was biaxially stretched at a predetermined temperature to prepare PET bases a to i having different thicknesses as shown in Table 1.

(Preparation of base material after subtraction)
Corona discharge treatment of 8 W / m ² · min is applied to both surfaces of the base materials a to d obtained above, and then the following undercoat coating solution a is applied to one surface so as to have a dry film thickness of 0.8 μm. After the coating, the undercoating liquid b was applied to a dry film thickness of 0.1 μm while performing corona discharge treatment (8 W / m ² · min), and each was dried at 180 ° C. for 4 minutes (undercoating surface A ). Also, after coating the following undercoat coating solution c on the opposite side so as to have a dry film thickness of 0.8 μm, the undercoat coating solution d is dried film thickness 1 while performing corona discharge treatment (8 W / m ² · min). The coated substrates were coated so as to have a thickness of 0.0 μm and dried at 180 ° C. for 4 minutes (undercoating surface B). Further, when the surface roughness of the surface on the undercoat surface B side was measured, the Ra value was 0.8 μm.

<< Undercoat coating liquid a >>
Styrene / glycidyl methacrylate / butyl acrylate = 60/39/1 ternary copolymer latex (Tg = 75 ° C.) 6.3% (based on solid content)
Styrene / glycidyl methacrylate / butyl acrylate = 20/40/40 terpolymer latex 1.6%
Anionic surfactant S-1 0.1%
Water 92.0%
<< Undercoat coating liquid b >>
Gelatin 1%
Anionic surfactant S-1 0.05%
Hardener H-1 0.02%
Matting agent (silica, average particle size 3.5 μm) 0.02%
Antifungal agent F-1 0.01%
Water 98.9%

<< Undercoat coating liquid c >>
Styrene / glycidyl methacrylate / butyl acrylate = 20/40/40 ternary copolymer latex 0.4% (based on solid content)
Styrene / glycidyl methacrylate / butyl acrylate / acetoacetoxyethyl methacrylate = 39/40/20/1 quaternary copolymer latex 7.6%
Anionic surfactant S-1 0.1%
Water 91.9%
<< Undercoat coating liquid d >>
Conductive composition of component d-11 / component d-12 / component d-13 = 66/31/1
6.4%
Hardener H-2 0.7%
Anionic surfactant S-1 0.07%
Matting agent (silica, average particle size 3.5 μm) 0.03%
Water 93.4%
Component d-11: Anionic polymer compound comprising a copolymer of sodium styrenesulfonate / maleic acid = 50/50 Component d-12: Three-component system comprising styrene / glycidyl methacrylate / butyl acrylate = 40/40/20 Copolymer latex component d-13: high molecular weight activator comprising styrene / sodium isoprenesulfonate = 80/20

(Preparation of roll-form development type printing plate material)
The coating liquid for hydrophilic layer 1 shown in Table 3 (preparation method is shown below) on the undercoating surface A of the above-described base materials A-1 to N-1, and for hydrophilic layer 2 shown in Table 4 The coating liquid (the preparation method is shown below) and the image forming functional layer coating liquid shown in Table 3 were applied on each surface A of the sublimated substrate using a wire bar. The order of coating, first, the hydrophilic layer 1 on a substrate, such that each dry coating weight using a wire bar in the order of hydrophilic layer 2 becomes ^{2.5g / m 2, 0.6g / m} 2 After coating and drying at 120 ° C. for 3 minutes, a heat treatment was performed at 60 ° C. for 24 hours. Thereafter, each of the image forming functional layer coating solutions shown in Table 5 was applied using a wire bar so that the drying weight was 0.6 g / m ² and dried at 50 ° C. for 3 minutes. The film was subjected to a seasoning treatment for 72 hours to produce a development type printing plate material on a belt-like machine. The produced on-press development type printing plate material is cut to 609 mm width and 32 m length so that the surface of the image functional layer is the outer surface of a hollow cylindrical core made of cardboard having an inner diameter of 71.9 mm and a wall thickness of 25 mm. Further, a resin-made flange having a diameter of 130 mm and a thickness of 3 mm is attached to both ends of the core to prepare a development-type printing plate material on a roll-shaped machine, which is shown in Table 6 as 1-1 to 1-4.

The stiffness used was a stiffness tester UT-100-230 manufactured by Toyo Seiki Seisakusho Co., Ltd., the sample size was 10 cm x 8 cm (effective area 8 cm x 8 cm), the deflection angle was 10 degrees, and the push-in amount was 1 mm. As measured.
<< Preparation of coating solution for hydrophilic layer 1 >>
Each raw material shown in Table 3 was sufficiently stirred and mixed using a homogenizer, and then mixed and filtered with the composition shown in Table 3 to prepare a coating solution for hydrophilic layer 1. In addition, the numerical value which shows the mixing ratio of each raw material in a table | surface represents a mass part.

<< Preparation of coating solution for hydrophilic layer 2 >>
Each material shown in Table 4 was sufficiently stirred and mixed using a homogenizer, and then mixed and filtered with the composition shown in Table 4 to prepare a coating solution for hydrophilic layer 2. In addition, the numerical value which shows the mixing ratio of each raw material in a table | surface represents a mass part.

<Preparation of coating solution for image forming functional layer>
Each material described in Table 5 was sufficiently stirred and mixed using a homogenizer, and then mixed and filtered with the composition described in Table 5 to prepare an image forming layer coating solution. In addition, the numerical value which shows the mixing ratio of each raw material in a table | surface represents a mass part.

(Preparation of on-machine development printing plate material exposure equipment)
Using Konica EV-laser Proofer (DDCP output machine equipped with a 808nm 32-channel semiconductor laser head), all standard adhesive rolls for removing foreign substances are changed to non-adhesive NBR rubber rolls. Then, the cutting part was modified by attaching it to the upper and lower blades of the suction mechanism as shown in FIG.

(Preparation of printing plate)
The prepared on-press development type printing plate material 1-1 to 1-4 is stored in a cartridge dedicated to the on-press development type printing plate material exposure device, and the prepared on-press development type printing plate material exposure device is prepared. As shown in Table 7, the suction conditions at the time of cutting are changed to match the on-roll development type printing plate materials 1-1 to 1-4, cut to 840 mm, conveyed onto the exposure drum, and attached under reduced pressure. It was set to automatically perform until it was fixed. On the printing plate material fixed on the exposure drum, the drum rotation speed is set so that the energy on the printing plate is 300 mJ / cm ^2, and a halftone dot image exposure corresponding to 175 lines is performed to prepare a printing plate, and samples 101 to 112 are used. did. At this time, the spot diameter of the exposure beam was about 18.5 μm, and the image writing resolution was 2400 dpi (dpi represents the number of dots per 2.54 cm).

(Evaluation)
Table 8 shows the results of evaluation of the produced printing plate materials 101 to 112 according to the following evaluation method and evaluation rank for image defects, dimension reproducibility, developability, and ink loading as printing plates under the following printing conditions. . The following two inks were used.

Printing machine: DAIYA1F-1 (Mitsubishi Heavy Industries, Ltd.)
Printing paper: Hokuetsu Paper Mucote 104.7g / m ²
Dampening solution: 2% by mass solution of Astro Mark 3 (Nikken Chemical Laboratories) Ink: (1) Toyo King Hi-Echo M Beni (Toyo Ink)
(2) TK High Echo SOY1 (soy oil ink manufactured by Toyo Ink Co.)
Evaluation of image defects, dimensional reproducibility, developability, and ink loading was performed according to the following method and evaluation rank.

1) Image Defects The entire surface (100%) image was exposed and printed, and the number of image defects caused by foreign matter generated in one screen was measured. 10 sheets were output continuously, 8 sheets from the 3rd sheet to the 10th sheet were printed and evaluated, and the average value per plate was obtained.

Evaluation rank ◎: Less than 0.1 pieces / plate ○: 0.1 to less than 0.3 pieces / plate △: 0.3 or more to less than 1.0 ×: 1.0 or more 2) Dimension reproducibility Continuous under the same conditions Ten sheets were output, and the lengths of two sides in the plate feeding direction were measured and averaged. Measurement was performed for all 10 plates, and the difference between the maximum and minimum average values was determined and used as the dimensional reproducibility. For the measurement, a three-dimensional measuring instrument (MICROCODE F604) manufactured by MITUTOYO was used.

Evaluation rank ○: Less than 0.3 mm △: 0.5 mm or more and less than 0.8 mm ×: 0.8 mm or more 3) Developability The printing start sequence is performed in the PS plate printing sequence, and ink smears in the non-image area are complete. The number of sheets until it disappeared was measured.

Evaluation rank ○: Less than 10 sheets Δ: 10 sheets or more and less than 30 sheets ×: 30 sheets or more 4) Ink riding The dampening water and the ink amount were changed to evaluate the finished prints for two types of inks.

Evaluation rank ○: Stable printing when ink amount standard is ± 50% or more △: Halftone dot color and solid density unevenness occurs in ink amount ± 30% region ×: Ink amount standard + less than 30% halftone dot color , Blurring, solid density unevenness

  The effectiveness of the present invention was confirmed.

Example 2
(Preparation of on-roll development type printing plate material)
The roll-type on-press development type printing plate material 1-106 prepared in Example 1 was used.

(Preparation of on-machine development printing plate material exposure equipment)
An air supply port and an exhaust port are further attached to the on-press development type printing plate material exposure apparatus prepared in Example 1, so that the inside of the on-press development type printing plate material exposure apparatus can be made positive with respect to the external pressure. I made it.
(Preparation of printing plate)
The prepared roll-form on-press development type printing plate material is stored in the cartridge for exclusive use of the prepared on-press development type printing plate material exposure device, loaded into the prepared on-press development type printing plate material exposure device, and at the time of cutting The suction conditions of the cutting section from the end of exposure to the discharge and the internal pressure conditions of the on-press development type printing plate material exposure apparatus are changed as shown in Table 9, cut to 840 mm, and conveyed onto the exposure drum It was set to automatically perform the process until it was fixed with reduced pressure contact. On the printing plate material fixed on the exposure drum, the drum rotation speed is set so that the energy on the printing plate is 300 mJ / cm ^2, and a halftone dot image exposure corresponding to 175 lines is performed to produce a printing plate, and samples 201 to 212 are used. did. At this time, the spot diameter of the exposure beam was about 18.5 μm, and the image writing resolution was 2400 dpi (dpi represents the number of dots per 2.54 cm). The air sent to the inside of the on-press development type printing plate material exposure apparatus was sent by an air compressor through a filter.

(Evaluation)
About the produced printing plate materials 201-212, evaluation results of image defects, dimensional reproducibility, developability, and ink loading as printing plates were evaluated by the same evaluation method as in Example 1, and the results of evaluation according to the same evaluation rank are shown. 10 shows.

  The effectiveness of the present invention was confirmed.

It is the schematic of a roll-form on-machine development type printing plate material. It is a schematic whole block diagram of exposure apparatus. FIG. 3 is an enlarged schematic view of a cutting part shown in FIG. 2.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Roll type on-machine development type printing plate material 104 Plastic film 105 Hydrophilic layer 106 Image forming layer 2 Exposure apparatus 3 On-machine development type printing plate material supply part 4 Cutting part 401 Upper blade 402 Lower blade 403 Mounting shaft 404 For upper blade Suction mechanism 406 Holder 406b Groove 406d Suction hole 5 Transport unit 6 Exposure unit 7 Discharge unit 8 Pressure adjustment unit 9 Main body

Claims (7)

An on-press development type printing plate material exposure apparatus having a cutting means for feeding a roll-form on-press development type printing plate material and cutting it to a predetermined size, wherein the cutting means has a suction mechanism. Exposure equipment for mold printing plate materials. The exposure apparatus for on-press development type printing plate material according to claim 1, wherein the suction mechanism performs vacuum suction from the start of feeding of the on-roll development type printing plate material to the end of cutting. The exposure apparatus for on-press development type printing plate material according to claim 1 or 2, wherein the cutting means has an upper blade and a lower blade. The on-machine development according to any one of claims 1 to 3, wherein the suction mechanism is a first suction unit provided on the upper blade and a second suction unit provided on the lower blade. Exposure equipment for mold printing plate materials. The on-roll development type printing plate material is fed out and cut into a predetermined size, and the cut sheet-like on-machine development type printing plate material is fixed on an exposure member, subjected to laser exposure, and the laser-exposed sheet In the on-machine development type printing plate material exposure apparatus for discharging the on-machine development type printing plate material,
The machine is characterized in that the interior is maintained at 20 to 250 Pa higher than the atmospheric pressure when at least the roll-form on-press development printing plate material and the sheet-form on-machine development printing plate material are moving. Exposure device for upper development type printing plate material. An exposure apparatus using an on-press development printing plate material having a hydrophilic layer and a heat-sensitive image forming layer in this order on a plastic film, and containing a photothermal conversion material for converting near infrared rays into heat in at least one layer 5. A printing plate production method for producing a printing plate by exposing to a printing plate, wherein the exposure device is the on-press development type printing plate material exposure device according to any one of claims 1 to 4. Plate making method. The printing plate according to claim 6, wherein the on-press development type printing plate material is a roll-type on-press development type printing plate material wound around a winding shaft so that the image forming layer side is an outer surface. Method.

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