JP2005262750A - Support for lithographic printing plate and original plate of lithographic printing plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a support for a lithographic printing plate which has a ripple structure of an average opening diameter of 0.01-0.2 μm in the surface and which makes sensitivity and plate wear resistance compatible at a high level and further brings about no intertwining of a net part. <P>SOLUTION: The support for the lithographic printing plate has in the surface a ripple structure formed of pits having an average opening diameter of 0.02-0.2 μm. The amount of zirconium in the surface is 0.5-30 mg/m<SP>2</SP>and the amount of phosphorus in the surface is 2-30 mg/m<SP>2</SP>. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a lithographic printing plate support and a lithographic printing plate precursor.

  The lithographic printing method is a printing method that utilizes the fact that water and oil are not essentially mixed. The printing plate surface of the lithographic printing plate used for this is a region that accepts water and repels oil-based ink (hereinafter referred to as “removal”). This region is referred to as a “non-image portion”) and a region that repels water and receives oil-based ink (hereinafter, this region is referred to as “image portion”).

An aluminum support for a lithographic printing plate used for a lithographic printing plate (hereinafter simply referred to as a “support for a lithographic printing plate”) is used so that its surface bears a non-image portion, and therefore has hydrophilicity and water retention. Are required to have various performances which are contradictory to each other, for example, excellent adhesion, and excellent adhesion to an image recording layer provided thereon. For example, stain resistance, sensitivity, and printing durability are in a trade-off relationship, and it is difficult to achieve both.
In contrast, Patent Document 1 discloses a support for a lithographic printing plate obtained by subjecting an aluminum plate to a surface roughening treatment and an anodizing treatment, and has an average opening diameter of 0.5 to 5 μm and an average wave structure. A support for a lithographic printing plate is described which has on its surface a grain shape having a structure in which a small wave structure having an opening diameter of 0.01 to 0.2 μm is superimposed.

JP 2003-112484 A

However, as a result of intensive studies by the inventor, the support for a lithographic printing plate described in Patent Document 1 has both a stain resistance and a printing durability at a high level. In an area ratio of 70 to 80%, it has been found that a phenomenon called “entanglement of halftone portions” where a portion around a halftone dot that originally becomes a non-image portion becomes an image portion may occur.
And this inventor discovered that the entanglement of the net | network part originates in the small wave structure of the surface average opening diameter of 0.01-0.2 micrometer.
Accordingly, the present invention provides a support for a lithographic printing plate having a small wave structure having an average opening diameter of 0.01 to 0.2 μm on the surface, wherein both sensitivity and printing durability are achieved at a high level, An object of the present invention is to provide a support for a lithographic printing plate in which no entanglement occurs, and a lithographic printing plate precursor using the same.

  As a result of further diligent research to achieve the above object, the present inventors have found that a specific amount of zirconium atoms and phosphorus atoms are present on the surface of a support having a small wave structure with an average aperture diameter of 0.01 to 0.2 μm on the surface. As a result, it was found that the entanglement of the net part can be extremely suppressed, and the present invention has been completed.

  That is, the present invention provides the following (i) to (vi).

(I) The surface has a small wave structure composed of pits having an average opening diameter of 0.02 to 0.2 μm, the surface zirconium content is 0.5 to 30 mg / m ² , and the surface phosphorus content is ² to 30 mg / m ^2. A lithographic printing plate support (the lithographic printing plate support according to the first aspect of the present invention), which is m ² .

(Ii) The lithographic printing plate support according to (i) above, wherein the amount of sodium on the surface is 1.0 mg / m ² and the amount of silicon on the surface is 0.1 to 3 mg / m ² .

  (Iii) A support for a lithographic printing plate having a small wave structure composed of pits having an average opening diameter of 0.02 to 0.2 μm on the surface, the surface satisfying the following formulas (1) and (2) The support for a lithographic printing plate according to the second aspect).

0.10 ≦ (A + B + C) / (A + B + C + D) ≦ 0.90 (1)
C> 1.0 (2)

A: Peak area (counts · eV / sec) of fluorine (1s) obtained by measurement using X-ray photoelectron spectroscopy
B: Peak area of zirconium (3d) obtained by measurement using X-ray photoelectron spectroscopy (counts · eV / sec)
C: Phosphorus (2p) peak area (counts · eV / sec) obtained by measurement using X-ray photoelectron spectroscopy
D: Peak area of aluminum (2p) obtained by measurement using X-ray photoelectron spectroscopy (counts · eV / sec)

  (Iv) It is obtained by subjecting an aluminum plate to treatment with an aqueous solution containing at least an inorganic fluorine compound and a phosphate compound, and then further treatment with an aqueous solution containing an alkali metal silicate. The lithographic printing plate support according to any one of (i) to (iii) above.

  (V) A lithographic printing plate precursor comprising an image recording layer provided on the lithographic printing plate support according to any one of (i) to (iv) above.

  (Vi) The lithographic printing plate precursor as described in (v) above, wherein the image recording layer is an image recording layer writable by infrared laser exposure.

  In the lithographic printing plate precursor according to the present invention using the lithographic printing plate support according to the present invention, the occurrence of entanglement of the mesh portion during printing is extremely suppressed.

Hereinafter, the present invention will be described in detail.
[Support for lithographic printing plate]
<Surface grain shape>
The support for a lithographic printing plate according to the present invention has a small wave structure formed of pits having an average opening diameter of 0.01 to 0.2 μm on the surface. Since the lithographic printing plate support of the present invention has the above-mentioned small wave structure on its surface, it has a function of holding the image recording layer by an anchor (throwing) effect and imparting printing durability. Further, when dampening water is supplied to the lithographic printing plate during printing, a water film is uniformly formed on the surface of the lithographic printing plate, thereby suppressing the occurrence of stains on the non-image area.
When the average opening diameter of the pits having the small wave structure is less than 0.01 μm, a large effect may not be obtained in forming a water film. On the other hand, if the average opening diameter of the pits having the small wave structure exceeds 0.2 μm, the medium wave structure described later may be destroyed, and the effect of improving the printing durability by the medium wave structure may not be obtained.

The small wave structure may be a structure overlapping with a medium wave structure composed of pits having an average aperture diameter of 0.5 to 5 μm and / or a large wave structure having an average wavelength of 5 to 100 μm.
Similar to the small wave structure, the medium wave structure with an average aperture diameter of 0.5 to 5 μm has a function of holding the image recording layer by an anchoring effect and imparting printing durability.
The large wave structure having an average wavelength of 5 to 100 μm has an effect of increasing the water retention amount on the surface of the non-image portion of the planographic printing plate. The more water is retained on the surface, the less the surface of the non-image area is affected by contamination in the atmosphere, and a non-image area that is less likely to get dirty even when the plate is left in the middle of printing can be obtained. Further, when the large wave structure is superimposed, it becomes easy to visually confirm the amount of dampening water given to the printing plate during printing. That is, the plate inspection property of the planographic printing plate is excellent. Furthermore, both the water ink balance and the ink wiping property are particularly excellent. If the average wavelength of the large wave structure is less than 5 μm, there may be no difference from the medium wave structure. If the average wavelength of the large wave structure exceeds 100 μm, the exposed non-image area may appear glaring after exposure and development, which may impair plate inspection. The average wavelength of the large wave structure is preferably 10 to 80 μm.

  The lithographic printing plate support of the present invention preferably has a triple structure on the surface in which the small wave structure, the medium wave structure, and the large wave structure are superimposed.

  In the lithographic printing plate support of the present invention, the method for measuring the average aperture diameter of the surface small wave structure, the average aperture diameter of the medium wave structure, and the average wavelength of the large waves is as follows.

(1) Average aperture diameter of the small wave structure The surface of the support was photographed at a magnification of 100,000 times from directly above using a high-resolution scanning electron microscope (SEM). At least 50 pits are extracted, the diameter is read to obtain the opening diameter, and the average of the opening diameters (average opening diameter) is calculated.

(2) Average opening diameter of medium wave structure The surface of the support was photographed at a magnification of 2,000 times from directly above using an electron microscope, and the medium wave in which the periphery of the pits was connected in a ring shape in the obtained electron micrograph. At least 50 pits (medium wave pits) having a structure are extracted, and the diameter is read to obtain the opening diameter, and the average opening diameter is calculated.

(3) the average wavelength stylus roughness meter large wave structure performs a two-dimensional roughness measurement, the average peak distance S _m as defined in ISO4287 were measured 5 times, and the average value as the average wavelength.

<Amount of specific elements present on the surface>
In the lithographic printing plate support according to the first aspect of the present invention, the amount of zirconium on the surface is 0.5 to 30 mg / m ² and the amount of phosphorus on the surface is ² to 30 mg / m ² . The amount of zirconium is preferably 20 mg / m ² or less. The amount of phosphorus is preferably 5 mg / m ² or more, and preferably 20 mg / m ² or less.
When the amount of zirconium on the surface is 0.5 mg / m ² or more and the amount of phosphorus on the surface is 2 mg / m ² or more, the sensitivity and the entanglement of the network are excellent. Further, when the surface zirconium amount is 30 mg / m ² or less and the surface phosphorus amount is 30 mg / m ² or less, the printing durability is excellent.

In the lithographic printing plate support of the first aspect of the present invention, the amount of sodium on the surface is preferably 1.0 mg / m ² or more. Within the above range, the balance of sensitivity, printing durability, and mesh entanglement is excellent. Moreover, it is preferable that the surface silicon amount is 0.1-3 mg / m < ² >. Within the above range, the balance of sensitivity, printing durability, and mesh entanglement is excellent.

  As the surface zirconium content, phosphorus content, sodium content, and silicon content, values measured by a calibration curve method using an X-ray Fluorescence Spectrometer (XRF) are used. As a standard sample for preparing a calibration curve, an aqueous solution containing a known amount of an element atom to be measured is uniformly dropped into an area of 30 mmφ on an aluminum plate and then dried. The model of the X-ray fluorescence analyzer and other conditions are not particularly limited.

  In the lithographic printing plate support of the second aspect of the present invention, the surface has a small wave structure composed of pits having an average opening diameter of 0.02 to 0.2 μm, and the surface is represented by the following formulas (1) and (2). Meet.

0.10 ≦ (A + B + C) / (A + B + C + D) ≦ 0.90 (1)
C> 1.0 (2)

A: Peak area (counts · eV / sec) of fluorine (1s) obtained by measurement using X-ray photoelectron spectroscopy
B: Peak area of zirconium (3d) obtained by measurement using X-ray photoelectron spectroscopy (counts · eV / sec)
C: Phosphorus (2p) peak area (counts · eV / sec) obtained by measurement using X-ray photoelectron spectroscopy
D: Peak area of aluminum (2p) obtained by measurement using X-ray photoelectron spectroscopy (counts · eV / sec)

In the above formula (1), “(A + B + C) / (A + B + C + D)” represents the degree of covering of the anodized film with the compound containing fluorine and zirconium and the phosphoric acid compound, and “(A + B + C) ) / (A + B + C + D) ”is larger, the coverage is higher, and the smaller is, the lower the coverage is.
When the value of “(A + B + C) / (A + B + C + D)” is 0.10 or more, the sensitivity and the entanglement of the mesh portion are excellent. Further, when the value of “(A + B + C) / (A + B + C + D)” is 0.90 or less, the printing durability is excellent. “(A + B + C) / (A + B + C + D)” is 0.10 or more, preferably 0.30 or more, and 0.90 or less, preferably 0.86 or less.
Further, as shown in the above formula (2), when C is larger than 1.0, the entanglement of the mesh portion becomes excellent. C is preferably 2.5 or more.

  X-ray photoelectron spectroscopy (ESCA) can be carried out by a conventional method.

Japanese Patent Application Laid-Open No. 2002-116549 describes a method for preparing a support by anodizing a metal plate mainly composed of aluminum and then treating it with an aqueous solution containing an inorganic fluorine compound and a phosphorus compound.
However, this method is intended to improve neglected dirt and sensitivity, and is not intended to suppress entanglement of the mesh portion. This is because the support that is the object of this method is not particularly limited in the above publication, but in that example, an electrochemical surface roughening treatment consisting of only one nitric acid electrolysis is performed. This is because such an electrochemical surface roughening treatment does not form a small wave structure having an average opening diameter of 0.02 to 0.2 μm as in the present invention, so that the entanglement of the net portion does not become a problem.
As described above, the present inventor is a problem of a support for a lithographic printing plate having a small wave structure having an average opening diameter of 0.02 to 0.2 μm that achieves both high stain resistance and printing durability. As a result of earnest research to solve the entanglement of the net part, it was found for the first time that the entanglement of the net part can be drastically suppressed by the presence of specific amounts of zirconium atoms and phosphorus atoms on the surface of the support. . Therefore, the present invention is not something that would be conceived by those skilled in the art from the above publication, and is extremely innovative.

<Surface treatment>
The lithographic printing plate support of the present invention is one in which the above-mentioned surface grain shape is formed on the surface of the aluminum plate by subjecting the aluminum plate described later to surface treatment. The lithographic printing plate support of the present invention is not particularly limited in its production process, but is preferably obtained by subjecting an aluminum plate to a surface roughening treatment, an anodizing treatment and a sealing treatment, and further after the sealing treatment. More preferably, it is obtained by applying a hydrophilic treatment. In particular, the aluminum plate is treated with an aqueous solution containing at least an inorganic fluorine compound and a phosphate compound (sealing treatment), and then further treated with an aqueous solution containing an alkali metal silicate (hydrophilic). It is preferable to obtain it.

In the following, as a representative method for forming the above-described surface grain shape,
A method of sequentially performing mechanical surface roughening treatment, alkali etching treatment, desmutting treatment with an acid and electrochemical surface roughening treatment using an electrolytic solution on an aluminum plate,
A method of performing mechanical surface roughening treatment, alkaline etching treatment, desmutting treatment with acid and electrochemical surface roughening treatment using different electrolytes a plurality of times on an aluminum plate,
A method of sequentially performing an alkali etching treatment, an acid desmutting treatment on an aluminum plate, and an electrochemical surface roughening treatment using an electrolytic solution,
Examples of the method include performing an alkali etching treatment, an acid desmutting treatment on an aluminum plate, and an electrochemical surface roughening treatment using different electrolytic solutions a plurality of times, but the present invention is not limited thereto. In these methods, after the electrochemical roughening treatment, an alkali etching treatment and an acid desmutting treatment may be further performed.
Hereinafter, each step of the surface treatment will be described in detail.

<Mechanical roughening>
The mechanical roughening treatment is effective as a roughening treatment means because it can form an uneven surface with an average wavelength of 5 to 100 μm at a lower cost than the electrochemical roughening treatment. is there.
Examples of the mechanical surface roughening treatment include, for example, a wire brush grain method in which the aluminum surface is scratched with a metal wire, a ball grain method in which the aluminum surface is grained with a polishing ball and an abrasive, JP-A-6-135175, and Japanese Patent Publication A brush grain method in which the surface is grained with a nylon brush and an abrasive described in Japanese Patent No. 50-40047 can be used.
A transfer method in which the uneven surface is pressed against the aluminum plate can also be used. That is, in addition to the methods described in JP-A-55-74898, JP-A-60-36195, and JP-A-60-20396, transfer is performed several times. The method described in JP-A-6-24168 and JP-A-6-24168 characterized in that the surface is elastic is also applicable.

In addition, by using electric discharge machining, shot blasting, laser, plasma etching, etc., a method of repeatedly transferring using a transfer roll etched with fine irregularities, and an uneven surface coated with fine particles on an aluminum plate It is also possible to use a method in which an uneven pattern corresponding to the average diameter of the fine particles is repeatedly transferred to the aluminum plate a plurality of times by contacting the surface and applying a pressure a plurality of times from above. As a method for imparting fine irregularities to the transfer roll, known methods described in JP-A-3-8635, JP-A-3-66404, JP-A-63-65017, etc. may be used. it can. Further, a fine groove may be cut from two directions using a die, a cutting tool, a laser, or the like on the roll surface, and the surface may be provided with square irregularities. The roll surface may be subjected to a known etching process or the like so that the formed square irregularities are rounded.
Further, in order to increase the surface hardness, quenching, hard chrome plating, or the like may be performed.
In addition, as the mechanical surface roughening treatment, methods described in JP-A Nos. 61-162351 and 63-104889 can be used.
In the present invention, the above-described methods can be used in combination in consideration of productivity and the like. These mechanical surface roughening treatments are preferably performed before the electrochemical surface roughening treatment.

Hereinafter, the brush grain method used suitably as a mechanical roughening process is demonstrated.
The brush grain method generally uses a roller-shaped brush in which a large number of brush hairs such as synthetic resin hair made of synthetic resin such as nylon (trade name), propylene, and vinyl chloride resin are implanted on the surface of a cylindrical body. This is carried out by rubbing one or both of the surfaces of the aluminum plate while spraying a slurry liquid containing an abrasive on a rotating roller brush. Instead of the roller brush and the slurry liquid, a polishing roller which is a roller having a polishing layer on the surface can be used.
When a roller brush is used, the flexural modulus is preferably 10,000 to 40,000 kg / cm ² , more preferably 15,000 to 35,000 kg / cm ² , and the bristle strength is preferably Brush hair of 500 gf or less, more preferably 400 gf or less is used. The diameter of the brush bristles is generally 0.2 to 0.9 mm. The length of the brush bristles can be appropriately determined according to the outer diameter of the roller brush and the diameter of the body, but is generally 10 to 100 mm.

A well-known thing can be used for an abrasive | polishing agent. For example, abrasives such as pumiston, silica sand, aluminum hydroxide, alumina powder, silicon carbide, silicon nitride, volcanic ash, carborundum, and gold sand; a mixture thereof can be used. Of these, pumiston and silica sand are preferable. In particular, silica sand is preferable in terms of excellent surface roughening efficiency because it is harder and less likely to break than Pamiston.
The average particle diameter of the abrasive is preferably 3 to 50 μm, and more preferably 6 to 45 μm in terms of excellent surface roughening efficiency and a narrow graining pitch.
For example, the abrasive is suspended in water and used as a slurry. In addition to the abrasive, the slurry liquid may contain a thickener, a dispersant (for example, a surfactant), a preservative, and the like. The specific gravity of the slurry liquid is preferably 0.5-2.

  As an apparatus suitable for the mechanical surface roughening treatment, for example, an apparatus described in Japanese Patent Publication No. 50-40047 can be given.

<Electrochemical roughening treatment>
In the electrochemical surface roughening treatment, an electrolytic solution used for the electrochemical surface roughening treatment using a normal alternating current can be used. Among them, the concavo-convex structure characteristic of the present invention can be formed on the surface by using an electrolytic solution mainly composed of hydrochloric acid or nitric acid.
As the electrolytic surface roughening treatment in the present invention, it is preferable to perform the first and second electrolytic treatments with an alternating waveform current in an acidic solution before and after the cathodic electrolytic treatment. By cathodic electrolysis, hydrogen gas is generated on the surface of the aluminum plate and smut is generated to make the surface state uniform, and it is possible to obtain a uniform electrolytic surface during the subsequent electrolysis with an alternating waveform current. .
This electrolytic surface roughening treatment can be performed according to, for example, an electrochemical grain method (electrolytic grain method) described in Japanese Patent Publication No. 48-28123 and British Patent No. 896,563. This electrolytic grain method uses a sinusoidal alternating current, but it may be performed using a special waveform as described in JP-A-52-58602. Further, the waveform described in JP-A-3-79799 can also be used. JP-A-55-158298, JP-A-56-28898, JP-A-52-58602, JP-A-52-152302, JP-A-54-85802, JP-A-60-190392, JP-A-58-120531, JP-A-63-176187, JP-A-1-5889, JP-A-1-280590, JP-A-1-118489, JP-A-1-148592, and JP-A-1-17896. JP-A-1-188315, JP-A-1-1549797, JP-A-2-235794, JP-A-3-260100, JP-A-3-253600, JP-A-4-72079, JP-A-4-72098, The methods described in JP-A-3-267400 and JP-A-1-141094 can also be applied. In addition to the above, it is also possible to perform electrolysis using an alternating current having a special frequency that has been proposed as a method of manufacturing an electrolytic capacitor. For example, it is described in US Pat. Nos. 4,276,129 and 4,676,879.

Various electrolyzers and power sources have been proposed. U.S. Pat. No. 4,023,637, JP-A-56-123400, JP-A-57-59770, JP-A-53-12738, JP-A-53. -32821, JP-A 53-32822, JP-A 53-32823, JP-A 55-122896, JP-A 55-13284, JP-A 62-127500, JP-A-1-52100 JP-A-1-52098, JP-A-60-67700, JP-A-1-230800, JP-A-3-257199 and the like can be used.
Further, JP-A-52-58602, JP-A-52-152302, JP-A-53-12738, JP-A-53-12739, JP-A-53-32821, JP-A-53-32822, JP 53-32833, JP 53-32824, JP 53-32825, JP 54-85802, JP 55-122896, JP 55-13284, JP 48-28123, JP-B-51-7081, JP-A-52-13338, JP-A-52-133840, JP-A-52-133844, JP-A-52-133845, JP-A-53- Nos. 149135 and 54-146234 can be used.

  As an acidic solution which is an electrolytic solution, in addition to nitric acid and hydrochloric acid, U.S. Pat. Nos. 4,671,859, 4,661,219, 4,618,405, 4,600, 482, 4,566,960, 4,566,958, 4,566,959, 4,416,972, 4,374,710, The electrolyte solution described in each specification of 4,336,113 and 4,184,932 can also be used.

  The concentration of the acidic solution is preferably 0.5 to 2.5% by mass, but it is particularly preferably 0.7 to 2.0% by mass in consideration of use in the smut removal treatment. Moreover, it is preferable that liquid temperature is 20-80 degreeC, and it is more preferable that it is 30-60 degreeC.

  An aqueous solution mainly composed of hydrochloric acid or nitric acid is an aqueous solution of hydrochloric acid or nitric acid having a concentration of 1 to 100 g / L, such as nitric acid compounds having nitrate ions such as aluminum nitrate, sodium nitrate, ammonium nitrate, aluminum chloride, sodium chloride, ammonium chloride, At least one of the hydrochloric acid compounds having hydrochloric acid ions can be used by adding in a range from 1 g / L to saturation. Moreover, the metal contained in aluminum alloys, such as iron, copper, manganese, nickel, titanium, magnesium, a silica, may melt | dissolve in the aqueous solution which has hydrochloric acid or nitric acid as a main component. Preferably, a solution obtained by adding aluminum chloride, aluminum nitrate or the like to an aqueous solution of hydrochloric acid or nitric acid having a concentration of 0.5 to 2% by mass so that aluminum ions are 3 to 50 g / L is preferably used.

Further, by adding and using a compound capable of forming a complex with Cu, uniform graining is possible even for an aluminum plate containing a large amount of Cu. Examples of the compound capable of forming a complex with Cu include ammonia; hydrogen atom of ammonia such as methylamine, ethylamine, dimethylamine, diethylamine, trimethylamine, cyclohexylamine, triethanolamine, triisopropanolamine, EDTA (ethylenediaminetetraacetic acid). And amines obtained by substituting with a hydrocarbon group (aliphatic, aromatic, etc.); metal carbonates such as sodium carbonate, potassium carbonate, potassium hydrogen carbonate and the like. In addition, ammonium salts such as ammonium nitrate, ammonium chloride, ammonium sulfate, ammonium phosphate, and ammonium carbonate are also included.
The temperature is preferably 10-60 ° C, more preferably 20-50 ° C.

  The AC power supply wave used for the electrochemical surface roughening treatment is not particularly limited, and a sine wave, a rectangular wave, a trapezoidal wave, a triangular wave or the like is used, but a rectangular wave or a trapezoidal wave is preferable, and a trapezoidal wave is particularly preferable. A trapezoidal wave means what was shown in FIG. In this trapezoidal wave, the time (TP) until the current reaches a peak from zero is preferably 1 to 3 msec. If it is less than 1 msec, processing irregularities such as chatter marks that occur perpendicular to the traveling direction of the aluminum plate are likely to occur. When TP exceeds 3 msec, especially when a nitric acid electrolyte is used, it is easily affected by trace components in the electrolyte typified by ammonium ions and the like that spontaneously increase by electrolytic treatment, and uniform graining is performed. It becomes hard to be broken. As a result, the stain resistance tends to decrease when a lithographic printing plate is obtained.

A trapezoidal wave alternating current duty ratio of 1: 2 to 2: 1 can be used. However, as described in Japanese Patent Laid-Open No. 5-195300, in an indirect power feeding method in which no conductor roll is used for aluminum. A duty ratio of 1: 1 is preferable.
A trapezoidal AC frequency of 0.1 to 120 Hz can be used, but 50 to 70 Hz is preferable in terms of equipment. When the frequency is lower than 50 Hz, the carbon electrode of the main electrode is easily dissolved, and when the frequency is higher than 70 Hz, it is easily affected by an inductance component on the power supply circuit, and the power supply cost is increased.

  One or more AC power supplies can be connected to the electrolytic cell. As shown in FIG. 3, the current ratio between the AC anode and cathode applied to the aluminum plate facing the main electrode is controlled to achieve uniform graining and to dissolve the carbon of the main electrode. In addition, it is preferable to install an auxiliary anode and divert part of the alternating current. In FIG. 3, 11 is an aluminum plate, 12 is a radial drum roller, 13a and 13b are main poles, 14 is an electrolytic treatment liquid, 15 is an electrolytic solution supply port, and 16 is a slit. , 17 is an electrolyte passage, 18 is an auxiliary anode, 19a and 19b are thyristors, 20 is an AC power source, 40 is a main electrolytic cell, and 50 is an auxiliary anode cell. An anodic reaction that acts on the aluminum plate facing the main electrode by diverting a part of the current value as a direct current to an auxiliary anode provided in a tank separate from the two main electrodes via a rectifier or switching element It is possible to control the ratio between the current value for the current and the current value for the cathode reaction. On the aluminum plate facing the main electrode, the ratio of the amount of electricity involved in the anodic reaction and the cathodic reaction (the amount of electricity at the time of cathode / the amount of electricity at the time of anode) is preferably 0.3 to 0.95.

  As the electrolytic cell, electrolytic cells used for known surface treatments such as a vertical type, a flat type, and a radial type can be used, but a radial type electrolytic cell as described in JP-A-5-195300 is particularly preferable. . The electrolytic solution passing through the electrolytic cell may be parallel to the traveling direction of the aluminum web or may be a counter.

(Nitric acid electrolysis)
Pits having an average opening diameter of 0.5 to 5 μm can be formed by electrochemical surface roughening using an electrolytic solution mainly composed of nitric acid. However, when the amount of electricity is relatively large, the electrolytic reaction is concentrated, and honeycomb pits exceeding 5 μm are also generated.
To obtain such a grain, the total amount of electricity furnished to anode reaction on the aluminum plate up until the electrolysis reaction is completed is preferably from ^{1~1000C / dm 2, 50~300C / dm} 2 It is more preferable that The current density at this time is preferably ²⁰ to 100 A / dm ² .
Further, when a high concentration or high temperature nitric acid electrolytic solution is used, a small wave structure having an average opening diameter of 0.2 μm or less can be formed.

(Hydrochloric acid electrolysis)
Since hydrochloric acid has a strong aluminum dissolving power, it is possible to form fine irregularities on the surface with only slight electrolysis. These fine irregularities have an average opening diameter of 0.01 to 0.2 μm and are uniformly generated on the entire surface of the aluminum plate. Such grained total amount of electricity furnished to anode reaction on the aluminum plate up until the electrolysis reaction is completed in order to obtain the, is preferably from 1~100C / dm ^2, in 20~70C / dm ² More preferably. The current density at this time is preferably ²⁰ to 50 A / dm ² .

In such an electrochemical surface roughening treatment with an electrolyte mainly composed of hydrochloric acid, a large crater-like swell is simultaneously formed by increasing the total amount of electricity involved in the anode reaction to 400 to 1000 C / dm ^2. In this case, fine irregularities having an average opening diameter of 0.01 to 0.4 μm are formed on the entire surface by being superimposed on a crater-like wave having an average opening diameter of 10 to 30 μm.

  In the present invention, as the first electrolytic surface roughening treatment, the above-described electrolytic surface roughening treatment (nitric acid electrolysis) using the electrolytic solution mainly composed of nitric acid is performed, and the second electrolytic surface roughening treatment is performed as described above. It is preferable to perform an electrolytic surface roughening treatment (hydrochloric acid electrolysis) using an electrolytic solution mainly composed of hydrochloric acid. That is, the present invention also provides a method for producing a lithographic printing plate support, in which at least an aluminum plate is subjected to nitric acid electrolysis and hydrochloric acid electrolysis sequentially as a roughening treatment, and further subjected to an anodic oxidation treatment to obtain a lithographic printing plate support. provide.

The aluminum plate is preferably subjected to cathodic electrolysis treatment during the first and second electrolytic surface-roughening treatments performed in the electrolytic solution such as nitric acid and hydrochloric acid. By this cathodic electrolysis treatment, smut is generated on the surface of the aluminum plate, and hydrogen gas is generated to enable more uniform electrolytic surface roughening treatment. This cathodic electrolysis treatment is carried out in an acidic solution at a cathode electric quantity of preferably 3 to 80 C / dm ² , more preferably 5 to 30 C / dm ² . If the amount of cathodic electricity is less than 3 C / dm ² , the amount of smut adhesion may be insufficient, and if it exceeds 80 C / dm ² , the amount of smut adhesion may be excessive. Further, the electrolytic solution may be the same as or different from the solution used in the first and second electrolytic surface roughening processes.

<Alkaline etching treatment>
The alkali etching treatment is a treatment for dissolving the surface layer by bringing the aluminum plate into contact with an alkali solution.

  Alkaline etching performed before the electrolytic surface roughening treatment removes rolling oil, dirt, natural oxide film, etc. on the surface of the aluminum plate (rolled aluminum) if mechanical surface roughening treatment is not performed. If the surface of the unevenness generated by the mechanical surface roughening treatment is dissolved, the surface with sharp undulations is smoothed. It is done for the purpose of changing.

If you do not mechanical surface-roughening treatment before the alkali etching treatment, the etching amount is preferably from 0.1 to 10 g / m ^2, and more preferably 1 to 5 g / m ^2. If the etching amount is less than 0.1 g / m ² , rolling oil, dirt, natural oxide film, etc. may remain on the surface, so uniform pits cannot be generated in the subsequent electrolytic surface roughening treatment, resulting in unevenness. May occur. On the other hand, when the etching amount is 1 to 10 g / m ² , the surface rolling oil, dirt, natural oxide film, and the like are sufficiently removed. An etching amount exceeding the above range is economically disadvantageous.

When performing mechanical surface-roughening treatment before the alkali etching treatment, the etching amount is preferably from 3 to 20 g / m ^2, and more preferably 5 to 15 g / m ^2. If the etching amount is less than 3 g / m ² , the unevenness formed by mechanical surface roughening or the like may not be smoothed, and uniform pit formation may not be possible in subsequent electrolytic treatment. In addition, the stain may deteriorate during printing. On the other hand, when the etching amount exceeds 20 g / m ² , the concavo-convex structure may disappear.

The alkali etching treatment performed immediately after the electrolytic surface roughening treatment is performed for the purpose of dissolving the smut generated in the acidic electrolytic solution and dissolving the edge portion of the pit formed by the electrolytic surface roughening treatment. .
Since the pits formed by the electrolytic surface roughening treatment are different depending on the type of the electrolytic solution, the optimum etching amount is also different. ² is preferred. When a nitric acid electrolyte is used, the etching amount needs to be set larger than when a hydrochloric acid electrolyte is used.
When the electrolytic surface roughening treatment is performed a plurality of times, an alkali etching treatment can be performed as necessary after each treatment.

  Examples of the alkali used in the alkaline solution include caustic alkali and alkali metal salts. Specifically, examples of caustic alkali include caustic soda and caustic potash. Examples of the alkali metal salt include alkali metal silicates such as sodium metasilicate, sodium silicate, potassium metasilicate, and potassium silicate; alkali metal carbonates such as sodium carbonate and potassium carbonate; sodium aluminate and alumina. Alkali metal aluminates such as potassium acid; alkali metal aldones such as sodium gluconate and potassium gluconate; dibasic sodium phosphate, dibasic potassium phosphate, tribasic sodium phosphate, tertiary potassium phosphate, etc. An alkali metal hydrogen phosphate is mentioned. Among these, a caustic alkali solution and a solution containing both a caustic alkali and an alkali metal aluminate are preferable from the viewpoint of high etching rate and low cost. In particular, an aqueous solution of caustic soda is preferable.

  Although the density | concentration of an alkaline solution can be determined according to the etching amount, it is preferable that it is 1-50 mass%, and it is more preferable that it is 10-35 mass%. When aluminum ions are dissolved in the alkaline solution, the concentration of aluminum ions is preferably 0.01 to 10% by mass, and more preferably 3 to 8% by mass. The temperature of the alkaline solution is preferably 20 to 90 ° C. The treatment time is preferably 1 to 120 seconds.

  Examples of the method of bringing the aluminum plate into contact with the alkaline solution include, for example, a method in which the aluminum plate is passed through a tank containing the alkaline solution, a method in which the aluminum plate is immersed in a tank containing the alkaline solution, The method of spraying on the surface of a board is mentioned.

<Desmut treatment>
After the electrolytic surface roughening treatment or the alkali etching treatment, pickling (desmut treatment) is performed to remove dirt (smut) remaining on the surface. Examples of the acid used include nitric acid, sulfuric acid, phosphoric acid, chromic acid, hydrofluoric acid, and borohydrofluoric acid.
The desmutting treatment is performed, for example, by bringing the aluminum plate into contact with an acidic solution having a concentration of 0.5 to 30% by mass (containing 0.01 to 5% by mass of aluminum ions) such as hydrochloric acid, nitric acid, and sulfuric acid. . Examples of the method of bringing the aluminum plate into contact with the acidic solution include, for example, a method of passing the aluminum plate through a bath containing the acidic solution, a method of immersing the aluminum plate in a bath containing the acidic solution, and an acidic solution containing aluminum. The method of spraying on the surface of a board is mentioned.
In the desmutting treatment, the acidic solution is mainly composed of an aqueous solution mainly composed of nitric acid or an aqueous solution mainly composed of hydrochloric acid discharged in the above-described electrolytic surface-roughening treatment, or sulfuric acid discharged in an anodic oxidation process described later. It is possible to use a waste solution of an aqueous solution.
It is preferable that the liquid temperature of a desmut process is 25-90 degreeC. Moreover, it is preferable that processing time is 1-180 second. Aluminum and aluminum alloy components may be dissolved in the acidic solution used for the desmut treatment.

<Anodizing treatment>
The aluminum plate treated as described above is further subjected to anodizing treatment. The anodizing treatment can be performed by a method conventionally used in this field. In this case, for example, in a solution having a sulfuric acid concentration of 50 to 300 g / L and an aluminum concentration of 5% by mass or less, an anodized film can be formed by energizing an aluminum plate as an anode. As a solution used for the anodizing treatment, sulfuric acid, phosphoric acid, chromic acid, oxalic acid, sulfamic acid, benzenesulfonic acid, amidosulfonic acid and the like can be used alone or in combination of two or more.

  Under the present circumstances, the component normally contained at least in an aluminum plate, an electrode, tap water, groundwater, etc. may be contained in electrolyte solution. Furthermore, the 2nd, 3rd component may be added. Examples of the second and third components herein include metal ions such as Na, K, Mg, Li, Ca, Ti, Al, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn; Cations such as ammonium ion; anions such as nitrate ion, carbonate ion, chloride ion, phosphate ion, fluoride ion, sulfite ion, titanate ion, silicate ion, borate ion, etc., 0 to 10000 ppm It may be contained at a concentration of about.

The conditions for anodizing treatment vary depending on the electrolyte used, and thus cannot be determined unconditionally. ˜60 A / dm ² , voltage 1 to 100 V, and electrolysis time 15 seconds to 50 minutes are appropriate and adjusted so as to obtain a desired anodic oxide film amount.

  Further, JP-A-54-81133, JP-A-57-47894, JP-A-57-51289, JP-A-57-51290, JP-A-57-54300, JP-A-57-136596, JP-A-58-107498, JP-A-60-200366, JP-A-62-136696, JP-A-63-176494, JP-A-4-17697, JP-A-4-280997, JP-A-6-280997 The methods described in JP-A-207299, JP-A-5-24377, JP-A-5-32083, JP-A-5-125597, JP-A-5-195291 and the like can also be used.

  Of these, as described in JP-A-54-12853 and JP-A-48-45303, it is preferable to use a sulfuric acid solution as the electrolytic solution. The sulfuric acid concentration in the electrolytic solution is preferably 10 to 300 g / L (1 to 30% by mass), and the aluminum ion concentration is 1 to 25 g / L (0.1 to 2.5% by mass). It is preferable that it is 2 to 10 g / L (0.2 to 1% by mass). Such an electrolytic solution can be prepared, for example, by adding aluminum sulfate or the like to dilute sulfuric acid having a sulfuric acid concentration of 50 to 200 g / L.

When anodizing is performed in an electrolytic solution containing sulfuric acid, direct current may be applied between the aluminum plate and the counter electrode, or alternating current may be applied.
When a direct current is applied to the aluminum plate, the current density is preferably from 1 to 60 A / dm ^2, and more preferably 5 to 40 A / dm ^2.
In the case where continuous anodizing treatment is performed, a low current of 5 to 10 A / m ² is initially introduced so that current is concentrated on a part of the aluminum plate and so-called “burning” does not occur. It is preferable to increase the current density to 30 to 50 A / dm ² or more as the current is passed at the density and the anodization process proceeds.
When the anodizing treatment is continuously performed, it is preferable that the anodizing process is performed by a liquid power feeding method in which power is supplied to the aluminum plate through an electrolytic solution.
By performing anodizing treatment under such conditions, a porous film having many pores called micropores can be obtained. Usually, the average pore diameter is about 5 to 50 nm, and the average pore density is 300. ˜800 / μm ² or so.

The amount of the anodized film is preferably 1 to 5 g / m ² . If it is less than 1 g / m ² , the plate tends to be damaged, while if it exceeds 5 g / m ² , a large amount of electric power is required for production, which is economically disadvantageous. The amount of the anodized film is more preferably 1.5 to 4 g / m ² . Moreover, it is preferable to carry out so that the difference in the amount of the anodized film between the center portion of the aluminum plate and the vicinity of the edge portion is 1 g / m ² or less.

As the electrolysis apparatus used for the anodizing treatment, those described in JP-A-48-26638, JP-A-47-18739, JP-B-58-24517, and the like can be used.
Among these, the apparatus shown in FIG. 4 is preferably used. FIG. 4 is a schematic view showing an example of an apparatus for anodizing the surface of an aluminum plate. In the anodizing apparatus 410, the aluminum plate 416 is transported as indicated by arrows in FIG. In the power supply tank 412 in which the electrolytic solution 418 is stored, the aluminum plate 416 is charged to (+) by the power supply electrode 420. The aluminum plate 416 is conveyed upward by the roller 422 in the power supply tank 412, changed in direction downward by the nip roller 424, and then conveyed toward the electrolytic treatment tank 414 in which the electrolytic solution 426 is stored. The direction is changed horizontally. Next, the aluminum plate 416 is charged to (−) by the electrolytic electrode 430 to form an anodized film on the surface thereof, and the aluminum plate 416 exiting the electrolytic treatment tank 414 is conveyed to a subsequent process. In the anodizing apparatus 410, the roller 422, the nip roller 424, and the roller 428 constitute a direction changing means, and the aluminum plate 416 is disposed between the power supply tank 412 and the electrolytic treatment tank 414 in the inter-tank section. By 428, it is conveyed into a mountain shape and an inverted U shape. The feeding electrode 420 and the electrolytic electrode 430 are connected to a DC power source 434.

  A feature of the anodizing apparatus 410 in FIG. 4 is that the feeding tank 412 and the electrolytic treatment tank 414 are partitioned by a single tank wall 432, and the aluminum plate 416 is conveyed in a mountain shape and an inverted U shape between the tanks. It is in. As a result, the length of the aluminum plate 416 in the inter-tank portion can be minimized. Therefore, the overall length of the anodizing apparatus 410 can be shortened, so that the equipment cost can be reduced. In addition, by conveying the aluminum plate 416 in a mountain shape and an inverted U shape, it is not necessary to form an opening for allowing the aluminum plate 416 to pass through the tank walls of the tanks 412 and 414. Therefore, since the liquid feeding amount required to maintain the liquid level height in each tank 412 and 414 at a required level can be suppressed, the operating cost can be reduced.

<Sealing treatment>
In the present invention, it is preferable to perform the sealing treatment after forming the anodized film on the aluminum plate as described above. By performing the sealing treatment, the amount of zirconium and the amount of phosphorus on the surface of the lithographic printing plate support of the present invention (in the lithographic printing plate support of the second aspect of the present invention, the fluorine amount) are described above. Specific range, and as a result, the entanglement of the net is greatly improved. That is, the entanglement of the ink in the mesh portion is extremely difficult to occur. In addition, the pore diameter of the micropores in the anodized film is reduced, which prevents the image recording layer from entering the inside of the micropores during the production of a lithographic printing plate precursor, thereby greatly improving developability. To do.

  The sealing treatment is preferably performed using an aqueous solution containing a fluorine compound and a phosphate compound. Among them, it is preferable to use an aqueous solution containing an inorganic fluorine compound and a phosphate compound.

As the fluorine compound, a metal fluoride is preferably exemplified.
Specifically, for example, sodium fluoride, potassium fluoride, calcium fluoride, magnesium fluoride, sodium fluoride zirconate, potassium fluoride zirconate, sodium fluoride titanate, potassium fluoride titanate, zircon fluoride Ammonium acid, ammonium fluoride titanate, potassium fluoride titanate, zirconate fluoride, titanate fluoride, hexafluorosilicic acid, nickel fluoride, iron fluoride, phosphor fluoride, ammonium fluoride phosphate It is done. Of these, sodium fluorinated zirconate, sodium fluorinated titanate, fluorinated zirconic acid, and fluorinated titanic acid are preferable.

Suitable examples of the phosphoric acid compound include phosphates of metals such as alkali metals and alkaline earth metals.
Specifically, for example, zinc phosphate, aluminum phosphate, ammonium phosphate, diammonium hydrogen phosphate, ammonium dihydrogen phosphate, monoammonium phosphate, monopotassium phosphate, monosodium phosphate, dihydrogen phosphate Potassium, dipotassium hydrogen phosphate, calcium phosphate, sodium ammonium hydrogen phosphate, magnesium hydrogen phosphate, magnesium phosphate, ferrous phosphate, ferric phosphate, sodium dihydrogen phosphate, sodium phosphate, hydrogen phosphate Disodium, lead phosphate, diammonium phosphate, calcium dihydrogen phosphate, lithium phosphate, phosphotungstic acid, phosphotungstic acid, sodium phosphotungstate, ammonium phosphomolybdate, sodium phosphomolybdate, sodium phosphite , Tripolyphosphate Potassium, and sodium pyrophosphate. Among these, sodium dihydrogen phosphate, disodium hydrogen phosphate, potassium dihydrogen phosphate, and dipotassium hydrogen phosphate are preferable.

  The combination of the fluorine compound and the phosphoric acid compound is not particularly limited, but it is preferable that the fluorine compound is sodium zirconate fluoride and the phosphate compound is sodium dihydrogen phosphate.

  The concentration of the fluorine compound in the aqueous solution is preferably 0.03% by mass or more, more preferably 0.05% by mass or more, and preferably 0.9% by mass or less. More preferably, it is 6 mass% or less.

  The concentration of the phosphoric acid compound in the aqueous solution is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and preferably 15% by mass or less, and 10% by mass. The following is more preferable.

  The ratio of each compound in the aqueous solution is not particularly limited, but the mass ratio of the fluorine compound and the phosphoric acid compound is preferably 1/200 to 10/1, more preferably 1/30 to 2/1. preferable.

Further, the temperature of the aqueous solution is preferably 40 ° C. or higher, more preferably 60 ° C. or higher, more preferably 95 ° C. or lower, and more preferably 80 ° C. or lower.
Further, the aqueous solution preferably has a pH of 3.0 or more, more preferably has a pH of 3.2 or more, preferably has a pH of 5.0 or less, and more preferably has a pH of 4.4 or less.

The manufacturing method of aqueous solution is not specifically limited, It can obtain by dissolving a fluorine compound and a phosphoric acid compound in water. In this case, the fluorine compound and the phosphate compound may be dissolved in water simultaneously or sequentially, or at least one of the fluorine compound and the phosphate compound may be dissolved in water and then mixed.
When using a phosphoric acid compound and a fluorine compound in powder form, it is preferable to first dissolve the fluorine compound in water in order to promote dissociation of the fluorine compound.

  The method for sealing treatment with an aqueous solution containing a fluorine compound is not particularly limited, and examples thereof include a dipping method and a spray method. These may be used alone or in combination, or may be used in combination of two or more.

<Hydrophilic treatment>
In the present invention, it is preferable to perform a hydrophilic treatment after the sealing treatment. Examples of the hydrophilization treatment include phosphomolybdate treatment described in US Pat. No. 3,201,247, alkyl titanate treatment described in British Patent No. 1,108,559, and German patent. Polyacrylic acid treatment described in US Pat. No. 1,091,433, polyvinyl phosphones described in German Patent No. 1,134,093 and British Patent No. 1,230,447 Acid treatment, phosphonic acid treatment described in JP-B 44-6409, phytic acid treatment described in US Pat. No. 3,307,951, JP-A 58-16893 and JP Treatment with a salt of a lipophilic organic polymer compound and a divalent metal described in JP-A-58-18291, described in US Pat. No. 3,860,426 As shown in the drawing, a treatment for providing an undercoat layer of a hydrophilic cellulose (for example, carboxymethylcellulose) containing a water-soluble metal salt (for example, zinc acetate), a sulfo group described in JP-A-59-101651 The process which undercoats the water-soluble polymer which has is mentioned.

Further, phosphates described in JP-A No. 62-019494, water-soluble epoxy compounds described in JP-A No. 62-033692, and JP-A No. 62-097892 Phosphate-modified starch, diamine compounds described in JP-A-63-056498, amino acid inorganic or organic acids described in JP-A-63-130391, JP-A-63-145092 Organic phosphonic acids containing carboxy group or hydroxy group, compounds having amino group and phosphonic acid group described in JP-A-63-165183, and JP-A-2-316290 Specific carboxylic acid derivatives, phosphate esters described in JP-A-3-215095, JP-A-3-261592 Compounds having one amino group and one oxygen acid group of phosphorus described in the publication, phosphoric esters described in JP-A-3-215095, and JP-A-5-246171 Aliphatic or aromatic phosphonic acids such as phenylphosphonic acid, compounds containing S atoms such as thiosalicylic acid described in JP-A-1-307745, and phosphorus described in JP-A-4-282737 Examples of the treatment include undercoating using a compound having a group of oxygen acids.
Further, coloring with an acid dye described in JP-A-60-64352 can also be performed.

  Hydrophilicity can also be achieved by soaking in an aqueous solution of an alkali metal silicate such as sodium silicate or potassium silicate, or by applying a hydrophilic vinyl polymer or hydrophilic compound to form a hydrophilic primer layer. It is preferable to carry out the treatment.

Hydrophilization treatment with an aqueous solution of an alkali metal silicate such as sodium silicate and potassium silicate is described in US Pat. No. 2,714,066 and US Pat. No. 3,181,461. It can be performed according to methods and procedures.
Examples of the alkali metal silicate include sodium silicate, potassium silicate, and lithium silicate. Of these, sodium silicate is preferred. The aqueous solution of alkali metal silicate may contain an appropriate amount of sodium hydroxide, potassium hydroxide, lithium hydroxide or the like.
The aqueous solution of alkali metal silicate may contain an alkaline earth metal salt or a Group 4 (Group IVA) metal salt. Examples of the alkaline earth metal salt include nitrates such as calcium nitrate, strontium nitrate, magnesium nitrate, and barium nitrate; sulfates; hydrochlorides; phosphates; acetates; oxalates; Examples of the Group 4 (Group IVA) metal salt include titanium tetrachloride, titanium trichloride, potassium fluoride titanium, potassium oxalate, titanium sulfate, titanium tetraiodide, zirconium chloride, zirconium dioxide, zirconium oxychloride. And zirconium tetrachloride. These alkaline earth metal salts and Group 4 (Group IVA) metal salts are used alone or in combination of two or more.

The amount of Si adsorbed by the alkali metal silicate treatment can be measured with a fluorescent X-ray analyzer, and the amount of adsorption is preferably 0.1 to 3.0 mg / m ² , and 0.5 to 1. More preferably, it is 5 mg / m ² .
By this alkali metal silicate treatment, the effect of improving the dissolution resistance to the alkaline developer on the surface of the lithographic printing plate support is obtained, the dissolution of the aluminum component into the developer is suppressed, and the developer fatigue It is possible to reduce the occurrence of development residue due to the above.

The hydrophilization treatment by forming a hydrophilic undercoat layer can also be performed according to the conditions and procedures described in JP-A Nos. 59-101651 and 60-149491.
Examples of the hydrophilic vinyl polymer used in this method include polyvinyl sulfonic acid, a sulfo group-containing vinyl polymerizable compound such as p-styrene sulfonic acid having a sulfo group, and ordinary vinyl polymerization such as (meth) acrylic acid alkyl ester. And a copolymer with a functional compound. Examples of hydrophilic compounds that may be used in this method include, -NH ₂ group, compounds having at least one selected from the group consisting of -COOH group and sulfo group.

<Washing treatment>
It is preferable to perform water washing after the completion of the above-described processes. For washing, pure water, well water, tap water, or the like can be used. A nip device may be used to prevent the processing liquid from being brought into the next process.

<Aluminum plate (rolled aluminum)>
In order to obtain the lithographic printing plate support of the present invention, a known aluminum plate can be used. The aluminum plate used in the present invention is a metal whose main component is dimensionally stable aluminum, and is made of aluminum or an aluminum alloy. In addition to a pure aluminum plate, an alloy plate containing aluminum as a main component and a trace amount of foreign elements can also be used.

  In the present specification, various substrates made of the above-described aluminum or aluminum alloy are generically used as an aluminum plate. The foreign elements that may be contained in the aluminum alloy include silicon, iron, manganese, copper, magnesium, chromium, zinc, bismuth, nickel, titanium, and the content of the foreign elements in the alloy is 10% by mass or less. It is.

  Thus, the composition of the aluminum plate used in the present invention is not specified. For example, a conventionally known material described in the fourth edition of the Aluminum Handbook (1990, published by the Light Metal Association), for example, JIS Al-Mn aluminum plates such as A1050, JIS A1100, JIS A1070, JIS A3004 containing Mn, and internationally registered alloy 3103A can be appropriately used. For the purpose of increasing the tensile strength, an Al—Mg alloy or an Al—Mn—Mg alloy (JIS A3005) in which 0.1% by mass or more of magnesium is added to these aluminum alloys can also be used. Furthermore, an Al—Zr alloy or an Al—Si alloy containing Zr or Si can also be used. Furthermore, an Al—Mg—Si based alloy can also be used.

  Regarding the JIS 1050 material, the techniques proposed by the applicant of the present application are disclosed in Japanese Patent Application Laid-Open Nos. 59-153861, 61-51395, 62-146694, 60-215725, and 60-215725. JP 60-215726, JP 60-215727, JP 60-216728, JP 61-272367, JP 58-11759, JP 58-42493, JP 58- 221254, JP-A-62-148295, JP-A-4-254545, JP-A-4-165541, JP-B-3-68939, JP-A-3-234594, JP-B-1-47545, and JP-A-62. It is described in each publication of -140894. In addition, techniques described in Japanese Patent Publication No. 1-35910 and Japanese Patent Publication No. 55-28874 are also known.

  Regarding the JIS1070 material, the techniques proposed by the applicant of the present application are disclosed in JP-A-7-81264, JP-A-7-305133, JP-A-8-49034, JP-A-8-73974, JP-A-8-108659 and It is described in JP-A-8-92679.

  Regarding Al-Mg alloys, the techniques proposed by the applicant of the present application are disclosed in Japanese Patent Publication Nos. Sho 62-5080, Sho 63-60823, Shoko 3-61753, JP Sho 60-20396, JP-A-60-203497, JP-B-3-11635, JP-A-61-274993, JP-A-62-23794, JP-A-63-47347, JP-A-63-47348, JP-A-63-47349. JP-A 64-1293, JP-A 63-135294, JP-A 63-87288, JP-B 4-73392, JP-B 7-100844, JP-A 62-149856, JP-B JP-A-4-73394, JP-A-62-181191, JP-B-5-76530, JP-A-63-30294, and JP-B-6-37116. Also described in JP-A-2-215599, JP-A-61-201747, and the like.

  With regard to Al—Mn alloys, techniques proposed by the applicant of the present application are described in Japanese Patent Application Laid-Open Nos. 60-230951, 1-306288, and 2-293189. In addition, JP-B-54-42284, JP-B-4-19290, JP-B-4-19291, JP-B-4-19292, JP-A-61-35995, JP-A-64-51992, JP-A-4-19592, No. 226394, US Pat. No. 5,009,722, US Pat. No. 5,028,276 and the like.

  With regard to the Al—Mn—Mg alloy, techniques proposed by the applicant of the present application are described in Japanese Patent Application Laid-Open Nos. 62-86143 and 3-2222796. JP-B 63-60824, JP-A 60-63346, JP-A 60-63347, JP-A-1-293350, European Patent No. 223,737, US Pat. No. 4,818, No. 300, British Patent No. 1,222,777, etc.

  Regarding the Al—Zr alloy, the technique proposed by the applicant of the present application is described in Japanese Patent Publication No. 63-15978 and Japanese Patent Application Laid-Open No. 61-51395. Also described in JP-A-63-143234 and JP-A-63-143235.

  The Al—Mg—Si alloy is described in British Patent 1,421,710.

  In order to use an aluminum alloy as a plate material, for example, the following method can be employed. First, a molten aluminum alloy adjusted to a predetermined alloy component content is subjected to a cleaning process and cast according to a conventional method. In the cleaning process, in order to remove unnecessary gas such as hydrogen in the molten metal, flux treatment, degassing process using argon gas, chlorine gas, etc., so-called rigid media filter such as ceramic tube filter, ceramic foam filter, A filtering process using a filter that uses alumina flakes, alumina balls or the like as a filter medium, a glass cloth filter, or a combination of a degassing process and a filtering process is performed.

  These cleaning treatments are preferably performed in order to prevent defects caused by foreign matters such as non-metallic inclusions and oxides in the molten metal and defects caused by gas dissolved in the molten metal. Regarding filtering of the molten metal, JP-A-6-57432, JP-A-3-162530, JP-A-5-140659, JP-A-4-231425, JP-A-4-276031, JP-A-5-311261, JP-A-5-311261 6-136466 and the like. Further, the degassing of the molten metal is described in JP-A-5-51659, Japanese Utility Model Laid-Open No. 5-49148, and the like. The applicant of the present application has also proposed a technique relating to degassing of molten metal in Japanese Patent Application Laid-Open No. 7-40017.

Next, casting is performed using the molten metal that has been subjected to the cleaning treatment as described above. Regarding the casting method, there are a method using a solid mold typified by a DC casting method and a method using a driving mold typified by a continuous casting method.
In DC casting, solidification occurs at a cooling rate of 0.5 to 30 ° C./second. When the temperature is less than 1 ° C., many coarse intermetallic compounds may be formed. When DC casting is performed, an ingot having a thickness of 300 to 800 mm can be manufactured. The ingot is chamfered as necessary according to a conventional method, and usually 1 to 30 mm, preferably 1 to 10 mm, of the surface layer is cut. Before and after that, soaking treatment is performed as necessary. When performing a soaking treatment, heat treatment is performed at 450 to 620 ° C. for 1 to 48 hours so that the intermetallic compound does not become coarse. If the heat treatment is shorter than 1 hour, the effect of soaking may be insufficient.

  Then, hot rolling and cold rolling are performed to obtain a rolled aluminum plate. An appropriate starting temperature for hot rolling is 350 to 500 ° C. An intermediate annealing treatment may be performed before or after hot rolling or in the middle thereof. The conditions for the intermediate annealing treatment are heating at 280 to 600 ° C. for 2 to 20 hours, preferably 350 to 500 ° C. for 2 to 10 hours using a batch annealing furnace, or 400 to 600 ° C. using a continuous annealing furnace. Heating is performed for 6 minutes or less, preferably 450 to 550 ° C. for 2 minutes or less. The crystal structure can be made finer by heating at a heating rate of 10 to 200 ° C./second using a continuous annealing furnace.

  The flatness of the aluminum plate finished to a predetermined thickness, for example, 0.1 to 0.5 mm by the above steps may be further improved by a correction device such as a roller leveler or a tension leveler. The flatness may be improved after the aluminum plate is cut into a sheet shape, but in order to improve the productivity, it is preferably performed in a continuous coil state. Further, a slitter line may be used for processing into a predetermined plate width. Moreover, in order to prevent generation | occurrence | production of the damage | wound by friction between aluminum plates, you may provide a thin oil film on the surface of an aluminum plate. As the oil film, a volatile or non-volatile film is appropriately used as necessary.

  On the other hand, as the continuous casting method, a twin roll method (hunter method), a method using a cooling roll typified by the 3C method, a double belt method (Hazley method), a cooling belt or a cooling block typified by Al-Swiss Caster II type The method using is industrially performed. When the continuous casting method is used, it solidifies at a cooling rate of 100 to 1000 ° C./second. Since the continuous casting method generally has a higher cooling rate than the DC casting method, it has a feature that the solid solubility of the alloy component in the aluminum matrix can be increased. Regarding the continuous casting method, the techniques proposed by the applicant of the present application are disclosed in JP-A-3-79798, JP-A-5-201166, JP-A-5-156414, JP-A-6-262203, and JP-A-6-122949. JP-A-6-210406 and JP-A-6-26308.

  When continuous casting is performed, for example, if a method using a cooling roll such as a Hunter method is used, a cast plate having a thickness of 1 to 10 mm can be directly cast continuously, and the hot rolling step is omitted. The advantage of being able to In addition, when a method using a cooling belt such as the Husley method is used, a cast plate having a thickness of 10 to 50 mm can be cast. Generally, a hot rolling roll is arranged immediately after casting and continuously rolled. Thus, a continuous cast and rolled plate having a thickness of 1 to 10 mm is obtained.

  These continuous cast and rolled plates are subjected to processes such as cold rolling, intermediate annealing, improvement of flatness, slits, and the like in the same manner as described for DC casting. Finished to a thickness of 5 mm. Regarding the intermediate annealing condition and the cold rolling condition when using the continuous casting method, the techniques proposed by the applicant of the present application are disclosed in JP-A-6-220593, JP-A-6-210308, JP-A-7-54111, It is described in JP-A-8-92709.

Various characteristics described below are desired for the aluminum plate thus manufactured.
As for the strength of the aluminum plate, it is preferable that the 0.2% proof stress is 140 MPa or more in order to obtain the stiffness required for a lithographic printing plate support. Moreover, in order to obtain a certain level of waist strength even when performing a burning treatment, the 0.2% yield strength after heat treatment at 270 ° C. for 3 to 10 minutes is preferably 80 MPa or more, and 100 MPa or more. It is more preferable that In particular, when the waist strength is required for an aluminum plate, an aluminum material added with Mg or Mn can be used, but if the waist is strengthened, the ease of fitting to the plate cylinder of a printing press becomes inferior. Depending on the application, the material and the amount of trace components added are appropriately selected. With regard to these, techniques proposed by the applicant of the present application are described in Japanese Patent Application Laid-Open Nos. 7-126820 and 62-140894.

  The crystal structure of the aluminum plate may cause poor surface quality when the surface of the aluminum plate is subjected to chemical or electrochemical surface roughening. It is preferably not too coarse. The crystal structure on the surface of the aluminum plate preferably has a width of 200 μm or less, more preferably 100 μm or less, still more preferably 50 μm or less, and the length of the crystal structure is 5000 μm or less. Is preferably 1000 μm or less, and more preferably 500 μm or less. With regard to these, techniques proposed by the applicant of the present application are described in Japanese Patent Laid-Open Nos. 6-218495, 7-39906, and 7-124609.

  The alloy component distribution of the aluminum plate, when chemical surface roughening treatment or electrochemical surface roughening treatment is performed, poor surface quality occurs due to non-uniform distribution of the alloy component on the surface of the aluminum plate. Therefore, it is preferable that the surface is not very uneven. With regard to these, the techniques proposed by the applicant of the present application are described in Japanese Patent Laid-Open Nos. 6-48058, 5-301478, and 7-132689.

  In the intermetallic compound of the aluminum plate, the size and density of the intermetallic compound may affect the chemical roughening treatment or the electrochemical roughening treatment. With regard to these, techniques proposed by the applicant of the present application are described in Japanese Patent Laid-Open Nos. 7-138687 and 4-254545.

  In the present invention, an aluminum plate as shown above can be used with unevenness by lamination rolling, transfer or the like in the final rolling step.

The aluminum plate used in the present invention is a continuous belt-like sheet material or plate material. That is, it may be an aluminum web or a sheet-like sheet cut to a size corresponding to a planographic printing plate precursor shipped as a product.
Since scratches on the surface of the aluminum plate may become defects when processed into a lithographic printing plate support, it is possible to generate scratches at the stage prior to the surface treatment process for making a lithographic printing plate support It is necessary to suppress as much as possible. For that purpose, it is preferable that the package has a stable form and is not easily damaged during transportation.
In the case of an aluminum web, for example, the packing form of aluminum is, for example, laying a hardboard and felt on an iron pallet, applying cardboard donut plates to both ends of the product, wrapping the whole with a polytube, and inserting a wooden donut into the inner diameter of the coil Then, a felt is applied to the outer periphery of the coil, the band is squeezed with a band, and the display is performed on the outer periphery. Moreover, a polyethylene film can be used as the packaging material, and a needle felt or a hard board can be used as the cushioning material. There are various other forms, but the present invention is not limited to this method as long as it is stable and can be transported without being damaged.

  The thickness of the aluminum plate used in the present invention is about 0.1 mm to 0.6 mm, preferably 0.15 mm to 0.4 mm, and more preferably 0.2 mm to 0.3 mm. This thickness can be appropriately changed according to the size of the printing press, the size of the printing plate, the user's desires, and the like.

<Back coat layer>
The support for a lithographic printing plate obtained as described above has a back surface (a surface on which the image recording layer is not provided) so that the image recording layer is not damaged even if it is overlaid when the lithographic printing plate precursor is used. ) May be provided with a coating layer made of an organic polymer compound (hereinafter also referred to as “backcoat layer”) as necessary.
As a main component of the back coat layer, at least one resin selected from the group consisting of a saturated copolymerized polyester resin, a phenoxy resin, a polyvinyl acetal resin, and a vinylidene chloride copolymer resin having a glass transition point of 20 ° C. or higher is used. Is preferred.

  The saturated copolyester resin is composed of a dicarboxylic acid unit and a diol unit. Examples of the dicarboxylic acid unit include aromatic dicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, tetrabromophthalic acid, and tetrachlorophthalic acid; adipic acid, azelaic acid, succinic acid, oxalic acid, suberic acid, and sebacic acid , Saturated aliphatic dicarboxylic acids such as malonic acid and 1,4-cyclohexanedicarboxylic acid.

  The backcoat layer further comprises a dye or pigment for coloring, a silane coupling agent for improving the adhesion to the support, a diazo resin comprising a diazonium salt, an organic phosphonic acid, an organic phosphoric acid, a cationic polymer, Wax, higher fatty acids, higher fatty acid amides, silicone compounds composed of dimethylsiloxane, modified dimethylsiloxane, polyethylene powder and the like that are usually used as slipping agents can be appropriately contained.

  The thickness of the backcoat layer may basically be such that even if no interleaf is present, the recording layer to be described later is hardly damaged, and is preferably 0.01 to 8 μm. When the thickness is less than 0.01 μm, it is difficult to prevent the recording layer from being scratched when the planographic printing plate precursors are handled in layers. On the other hand, when the thickness exceeds 8 μm, the backcoat layer swells due to chemicals used around the lithographic printing plate during printing, the thickness varies, and the printing pressure may change to deteriorate the printing characteristics.

  Various methods can be used as a method of providing the back coat layer on the back surface of the support. For example, a method in which the above components for the back coat layer are dissolved in an appropriate solvent and applied as a solution, or an emulsified dispersion is applied and dried; a previously formed film is supported with an adhesive or heat. The method of bonding to a body; The method of forming a molten film with a melt extruder and bonding to a support body is mentioned. The most preferable method for securing a suitable thickness is a method in which the components for the backcoat layer are dissolved in a suitable solvent, applied as a solution, and dried. In this method, an organic solvent as described in JP-A-62-251739 can be used alone or in combination as a solvent.

  In the production of a lithographic printing plate precursor, either the back coat layer on the back surface or the image recording layer on the front surface may be provided on the support first, or both may be provided simultaneously.

[Lithographic printing plate precursor]
<Image recording layer>
The lithographic printing plate support obtained by the present invention can be provided with an image recording layer to form the lithographic printing plate precursor of the present invention. A photosensitive composition is used for the image recording layer.
The photosensitive composition suitably used in the present invention is not particularly limited. For example, a thermal positive photosensitive composition containing an alkali-soluble polymer compound and a photothermal conversion substance (hereinafter referred to as this composition and the composition). The image recording layer was referred to as “thermal positive type”), a thermal negative photosensitive composition containing a curable compound and a photothermal conversion substance (hereinafter also referred to as “thermal negative type”), and photopolymerization type photosensitive. Composition (hereinafter also referred to as “photopolymer type”), negative photosensitive composition containing diazo resin or photocrosslinking resin (hereinafter also referred to as “conventional negative type”), positive containing quinonediazide compound Type photosensitive composition (hereinafter also referred to as "conventional positive type"), photosensitive composition that does not require a special development step (Referred to below as "non-treatment type".) And the like.
Further, the support for a lithographic printing plate obtained by the present invention is a thermal positive type, a thermal negative type, or the like, which carries digitized image information on a high-convergence radiation such as a laser beam, and uses that light. It is suitably used for computer-to-plate (CTP) technology in which a lithographic printing plate precursor is scanned and exposed to directly produce a lithographic printing plate without using a lithographic film. Therefore, an image recording layer that can be written by infrared laser exposure and used for such applications is preferable.
Hereinafter, these suitable photosensitive compositions will be described.

<Thermal positive type>
<Photosensitive layer>
The thermal positive type photosensitive composition contains an alkali-soluble polymer compound and a photothermal conversion substance. In the thermal positive type image recording layer, the photothermal conversion substance converts the energy of light such as infrared lasers into heat, and the heat efficiently cancels the interaction that reduces the alkali solubility of the alkali-soluble polymer compound. To do.

Examples of the alkali-soluble polymer compound include a resin containing an acidic group in the molecule and a mixture of two or more thereof. In particular, a phenolic hydroxy group, sulfonamide group (in -SO ₂ NH-R (wherein, R represents a hydrocarbon group.)), Active imino group _{(-SO 2 NHCOR, -SO 2 NHSO} 2 R, -CONHSO A resin having an acidic group such as ₂ R (wherein R has the same meaning as described above) is preferable in terms of solubility in an alkali developer.
In particular, a resin having a phenolic hydroxy group is preferable in that it has excellent image-forming properties when exposed to light such as an infrared laser, and examples thereof include phenol-formaldehyde resins, m-cresol-formaldehyde resins, p-cresol-formaldehyde resins, m- / p-mixed cresol-formaldehyde resin, phenol / cresol (any of m-, p- and m- / p-mixed) mixed-formaldehyde resin (phenol-cresol-formaldehyde co-condensation resin) and other novolak resins Are preferable.
Furthermore, the polymer compound described in JP-A No. 2001-305722 (particularly [0023] to [0042]), and the repetition represented by the general formula (1) described in JP-A No. 2001-215893 Preferred examples also include polymer compounds containing units, and polymer compounds described in JP-A No. 2002-311570 (particularly [0107]).

  Preferable examples of the photothermal conversion substance include pigments or dyes having a light absorption region in the infrared region having a wavelength of 700 to 1200 nm from the viewpoint of recording sensitivity. Examples of the dye include azo dyes, metal complex azo dyes, pyrazolone azo dyes, naphthoquinone dyes, anthraquinone dyes, phthalocyanine dyes, carbonium dyes, quinoneimine dyes, methine dyes, cyanine dyes, squarylium dyes, pyrylium salts, metal thiolate complexes (for example, , Nickel thiolate complex). Among these, cyanine dyes are preferable, and cyanine dyes represented by the general formula (I) described in JP 2001-305722 A are particularly preferable.

The thermal positive type photosensitive composition may contain a dissolution inhibitor. As the dissolution inhibitor, for example, dissolution inhibitors described in JP-A-2001-305722, [0053] to [0055] are preferably exemplified.
In addition, in the thermal positive type photosensitive composition, as a additive, a sensitivity modifier, a printing agent for obtaining a visible image immediately after heating by exposure, a compound such as a dye as an image colorant, a coating property In addition, it is preferable to include a surfactant for improving the processing stability. For these, compounds described in JP-A-2001-305722, [0056] to [0060] are preferable.
The photosensitive composition described in detail in Japanese Patent Application Laid-Open No. 2001-305722 is also preferably used in other respects.

Further, the thermal positive type image recording layer is not limited to a single layer but may have a two-layer structure.
As an image recording layer having a two-layer structure (multilayer image recording layer), a lower layer (hereinafter referred to as “A layer”) having excellent printing durability and solvent resistance is provided on the side close to the support, and a positive layer is provided thereon. A type provided with a layer having excellent image formability (hereinafter referred to as “B layer”) is preferable. This type has high sensitivity and can realize a wide development latitude. The B layer generally contains a photothermal conversion substance. Preferred examples of the photothermal conversion substance include the dyes described above.
As the resin used in the A layer, a polymer having a monomer having a sulfonamide group, an active imino group, a phenolic hydroxy group or the like as a copolymerization component is preferably used because it has excellent printing durability and solvent resistance. . As the resin used for the B layer, an alkaline aqueous solution-soluble resin having a phenolic hydroxy group is preferably exemplified.
In addition to the resin, the composition used for the A layer and the B layer can contain various additives as necessary. Specifically, various additives as described in JP-A-2002-3233769, [0062] to [0085] are preferably used. Further, the additives described in [0053] to [0060] of JP-A-2001-305722 described above are also preferably used.
About each component which comprises A layer and B layer, and its content, it is preferable to make it describe in Unexamined-Japanese-Patent No. 11-218914.

<Intermediate layer>
An intermediate layer is preferably provided between the thermal positive type image recording layer and the support. As the component contained in the intermediate layer, various organic compounds described in [0068] of JP-A No. 2001-305722 are preferably exemplified.

<Others>
As a method for producing a thermal positive type image recording layer and a plate making method, methods described in detail in JP-A No. 2001-305722 can be used.

<Thermal negative type>
The thermal negative photosensitive composition contains a curable compound and a photothermal conversion substance. The thermal negative type image recording layer is a negative photosensitive layer in which a portion irradiated with light such as an infrared laser is cured to form an image portion.
<Polymerized layer>
As one of the thermal negative type image recording layers, a polymerization type image recording layer (polymerization layer) is preferably exemplified. The polymerization layer contains a photothermal conversion substance, a radical generator, a radical polymerizable compound that is a curable compound, and a binder polymer. In the polymerization layer, infrared light absorbed by the light-to-heat conversion substance is converted into heat, the radical generator is decomposed by this heat to generate radicals, and the radical polymerizable compound is polymerized in a chain by the generated radicals and cured. .

As a photothermal conversion substance, the photothermal conversion substance used for the thermal positive type mentioned above is mentioned, for example. Specific examples of particularly preferred cyanine dyes include those described in JP-A-2001-133969, [0017] to [0019].
Preferred examples of the radical generator include onium salts. In particular, onium salts described in JP-A-2001-133969, [0030] to [0033] are preferable.
Examples of the radical polymerizable compound include compounds having at least one terminal ethylenically unsaturated bond, preferably two or more.
As the binder polymer, a linear organic polymer is preferably exemplified. Preferred examples include linear organic polymers that are soluble or swellable in water or weak alkaline water. Among them, a (meth) acrylic resin having an unsaturated group such as an allyl group or an acryloyl group or a benzyl group and a carboxy group in the side chain is preferable in that it has an excellent balance of film strength, sensitivity, and developability. .
As the radical polymerizable compound and the binder polymer, those described in detail in [0036] to [0060] of JP-A No. 2001-133969 can be used.

  In the thermal negative photosensitive composition, an additive described in JP-A-2001-133969, [0061] to [0068] (for example, a surfactant for improving coatability) is contained. Is preferred.

  As a method for producing the polymerization layer and a plate making method, methods described in detail in JP-A No. 2001-133969 can be used.

<Acid cross-linked layer>
Further, as one of the thermal negative type image recording layers, an acid cross-linked image recording layer (acid cross-linked layer) is also preferably exemplified. The acid cross-linking layer comprises a photothermal conversion substance, a thermal acid generator, a compound that cross-links with an acid that is a curable compound (cross-linking agent), and an alkali-soluble polymer compound that can react with the cross-linking agent in the presence of an acid. contains. In the acid cross-linking layer, infrared light absorbed by the photothermal conversion substance is converted into heat, the heat acid generator is decomposed by this heat to generate an acid, and the generated acid reacts with the cross-linking agent and the alkali-soluble polymer compound. And harden.

Examples of the photothermal conversion substance include the same substances as those used for the polymerization layer.
Examples of the thermal acid generator include thermal decomposition compounds such as photoinitiators for photopolymerization, photochromic agents for dyes, and acid generators used in microresists.
Examples of the crosslinking agent include an aromatic compound substituted with a hydroxymethyl group or an alkoxymethyl group; a compound having an N-hydroxymethyl group, an N-alkoxymethyl group or an N-acyloxymethyl group; and an epoxy compound.
Examples of the alkali-soluble polymer compound include a novolak resin and a polymer having a hydroxyaryl group in the side chain.

<Photopolymer type>
The photopolymerization type photosensitive composition contains an addition polymerizable compound, a photopolymerization initiator, and a polymer binder.
As the addition polymerizable compound, an ethylenically unsaturated bond-containing compound capable of addition polymerization is preferably exemplified. The ethylenically unsaturated bond-containing compound is a compound having a terminal ethylenically unsaturated bond. Specifically, for example, it has a chemical form such as a monomer, a prepolymer, and a mixture thereof. Examples of monomers include esters of unsaturated carboxylic acids (eg, acrylic acid, methacrylic acid, itaconic acid, maleic acid) and aliphatic polyhydric alcohol compounds, amides of unsaturated carboxylic acids and aliphatic polyvalent amine compounds. Is mentioned.
Moreover, as an addition polymerizable compound, a urethane type addition polymerizable compound is also preferably exemplified.

As the photopolymerization initiator, various photopolymerization initiators or a combination system (photoinitiation system) of two or more photopolymerization initiators can be appropriately selected depending on the wavelength of the light source to be used. For example, the initiation system described in JP-A-2001-22079, [0021] to [0023] is preferable.
The polymer binder not only functions as a film forming agent for the photopolymerization type photosensitive composition, but is soluble or swellable in alkaline water because the image recording layer needs to be dissolved in an alkaline developer. An organic high molecular polymer is used. As such an organic polymer, those described in JP-A-2001-22079, [0036] to [0063] are preferably exemplified.

  In the photopolymer type photopolymerization type photosensitive composition, additives described in JP-A-2001-22079, [0079] to [0088] (for example, a surfactant for improving coatability) , Colorants, plasticizers, thermal polymerization inhibitors).

Further, it is preferable to provide an oxygen-blocking protective layer on the photopolymer type image recording layer in order to prevent the action of inhibiting polymerization of oxygen. Examples of the polymer contained in the oxygen barrier protective layer include polyvinyl alcohol and copolymers thereof.
Furthermore, it is also preferable to provide an intermediate layer or an adhesive layer as described in [0124] to [0165] of JP-A-2001-228608.

<Conventional negative type>
The conventional negative-type photosensitive composition contains a diazo resin or a photocrosslinking resin. Among them, preferred is a photosensitive composition containing a diazo resin and an alkali-soluble or swellable polymer compound (binder).
Examples of the diazo resin include condensates of aromatic diazonium salts and active carbonyl group-containing compounds such as formaldehyde; condensates of p-diazophenylamines and formaldehyde with hexafluorophosphate or tetrafluoroborate. Organic solvent-soluble diazo resin inorganic salts which are reaction products of In particular, a high molecular weight diazo compound containing 20 mol% or more of a hexamer described in JP-A-59-78340 is preferable.
Examples of the binder include a copolymer containing acrylic acid, methacrylic acid, crotonic acid, or maleic acid as an essential component. Specifically, multi-component copolymers of monomers such as 2-hydroxyethyl (meth) acrylate, (meth) acrylonitrile, and (meth) acrylic acid as described in JP-A-50-118802, Examples thereof include multi-component copolymers composed of alkyl acrylate, (meth) acrylonitrile and unsaturated carboxylic acid as described in JP-A-56-4144.

  The conventional negative type photosensitive composition has, as additives, the bake-out agent, dye, and flexibility and abrasion resistance described in JP-A-7-281425, [0014] to [0015]. It is preferable to contain a plasticizer for imparting, a compound such as a development accelerator, and a surfactant for improving coating properties.

  Under the conventional negative type photosensitive layer, an intermediate layer containing a polymer compound having a component having an acid group and a component having an onium group as described in JP-A-2000-105462 is provided. Is preferred.

<Conventional positive type>
The conventional positive type photosensitive composition contains a quinonediazide compound. Among these, a photosensitive composition containing an o-quinonediazide compound and an alkali-soluble polymer compound is preferable.
Examples of the o-quinonediazide compound include esters of 1,2-naphthoquinone-2-diazide-5-sulfonyl chloride and phenol-formaldehyde resin or cresol-formaldehyde resin, described in US Pat. No. 3,635,709. And esters of 1,2-naphthoquinone-2-diazide-5-sulfonyl chloride and pyrogallol-acetone resin.
Examples of the alkali-soluble polymer compound include phenol-formaldehyde resin, cresol-formaldehyde resin, phenol-cresol-formaldehyde co-condensation resin, polyhydroxystyrene, N- (4-hydroxyphenyl) methacrylamide copolymer, A carboxy group-containing polymer described in JP-A-7-36184, an acrylic resin containing a phenolic hydroxy group as described in JP-A-51-34711, and described in JP-A-2-866 Examples thereof include acrylic resins having a sulfonamide group and urethane resins.

  Conventional positive type photosensitive compositions include compounds such as sensitivity modifiers, printing agents, dyes and the like described in JP-A-7-92660, [0024] to [0027] as additives. It is preferable to contain a surfactant for improving the coating property as described in [0031] of Kaihei 7-92660.

  Under the conventional positive type photosensitive layer, it is preferable to provide an intermediate layer similar to the intermediate layer suitably used for the above-described conventional negative type.

<Non-treatment type>
Examples of the non-processing type photosensitive composition include a thermoplastic fine particle polymer type, a microcapsule type, and a sulfonic acid-generating polymer-containing type. These are all heat-sensitive types containing a photothermal conversion substance. The photothermal conversion substance is preferably the same dye as that used in the above-described thermal positive type.

The thermoplastic fine particle polymer type photosensitive composition is obtained by dispersing a hydrophobic and heat-meltable fine particle polymer in a hydrophilic polymer matrix. In the image recording layer of the thermoplastic fine particle polymer type, the hydrophobic fine particle polymer is melted by heat generated by exposure and is fused to form a hydrophobic region, that is, an image portion.
As the fine particle polymer, those in which fine particles melt and coalesce with heat are preferable, and those having a hydrophilic surface and capable of being dispersed in a hydrophilic component such as dampening water are more preferable. Specifically, ResearchDisclosureNo. 33303 (January 1992), JP-A-9-123387, JP-A-9-131850, JP-A-9-171249, and JP-A-9-171250, and European Patent Application Publication No. 931,647. Preferred examples thereof include thermoplastic fine particle polymers. Of these, polystyrene and polymethyl methacrylate are preferred. Examples of the fine particle polymer having a hydrophilic surface include those in which the polymer itself is hydrophilic; those in which a hydrophilic compound such as polyvinyl alcohol and polyethylene glycol is adsorbed on the surface of the fine particle polymer to make the surface hydrophilic.
The fine particle polymer preferably has a reactive functional group.

  As a microcapsule type photosensitive composition, a compound having a heat-reactive functional group as described in JP-A No. 2000-118160 or JP-A No. 2001-277740 is included. A microcapsule type is preferable.

  Examples of the sulfonic acid generating polymer used in the sulfonic acid generating polymer-containing photosensitive composition include sulfonic acid ester groups, disulfone groups, and sec- or tert-sulfonamides described in JP-A No. 10-282672. Examples thereof include polymers having a group in the side chain.

  By incorporating a hydrophilic resin into the unprocessed photosensitive composition, not only on-press developability is improved, but also the film strength of the photosensitive layer itself is improved. Examples of the hydrophilic resin include those having a hydrophilic group such as hydroxy group, carboxy group, hydroxyethyl group, hydroxypropyl group, amino group, aminoethyl group, aminopropyl group, carboxymethyl group, and hydrophilic sol-gel conversion system. A binder resin is preferred.

  The unprocessed type image recording layer does not require a special development step and can be developed on a printing press. As a method for producing an unprocessed image recording layer and a plate-making printing method, methods described in detail in JP-A No. 2002-178655 can be used.

<Overcoat layer>
In the untreated type lithographic printing plate precursor, a water-soluble overcoat layer can be provided on the image recording layer in order to prevent contamination of the surface of the heat-sensitive layer with an oleophilic substance. The water-soluble overcoat layer used in the present invention is preferably one that can be easily removed during printing, and contains a resin selected from water-soluble organic polymer compounds.
As the water-soluble organic polymer compound, a film formed by coating and drying has film-forming ability. Specifically, for example, polyvinyl acetate (however, a hydrolysis rate of 65% or more), polyacrylic Acid and its alkali metal salt or amine salt, polyacrylic acid copolymer and its alkali metal salt or amine salt, polymethacrylic acid and its alkali metal salt or amine salt, polymethacrylic acid copolymer and its alkali metal salt or amine Salt, polyacrylamide and copolymer thereof, polyhydroxyethyl acrylate, polyvinylpyrrolidone and copolymer thereof, polyvinyl methyl ether, polyvinyl methyl ether / maleic anhydride copolymer, poly-2-acrylamide-2-methyl-1- Propanesulfonic acid and its alkenyl Metal salt or amine salt, poly-2-acrylamido-2-methyl-1-propanesulfonic acid copolymer and alkali metal salt or amine salt thereof, gum arabic, fiber derivative (for example, carboxymethyl cellulose, carboxyethyl cellulose, Methyl cellulose, etc.) and modified products thereof, white dextrin, pullulan, enzymatically decomposed etherified dextrin and the like. In addition, two or more of these resins can be mixed and used depending on the purpose.

Moreover, you may add a water-soluble thing among the photothermal conversion agents mentioned above to an overcoat layer. Furthermore, for the purpose of ensuring the uniformity of coating, a nonionic surfactant such as polyoxyethylene nonylphenyl ether or polyoxyethylene dodecyl ether can be added to the overcoat layer in the case of aqueous solution coating. .
The dry coating amount of the overcoat layer is preferably 0.1 to 2.0 g / m ² . Within this range, the on-press developability is not impaired, and the surface of the heat-sensitive layer can be satisfactorily prevented from being contaminated with lipophilic substances such as fingerprints.

[Manufacture of lithographic printing plates]
The lithographic printing plate precursor using the lithographic printing plate support obtained by the present invention is converted into a lithographic printing plate by various treatment methods according to the image recording layer.
Examples of the actinic ray light source used for image exposure include a mercury lamp, a metal halide lamp, a xenon lamp, and a chemical lamp. Examples of the laser beam include a helium-neon laser (He-Ne laser), an argon laser, a krypton laser, a helium-cadmium laser, a KrF excimer laser, a semiconductor laser, a YAG laser, and a YAG-SHG laser.

After the above exposure, if the image recording layer is any of thermal positive type, thermal negative type, conventional negative type, conventional positive type, and photopolymer type, after exposure, it is developed using a developer to obtain a lithographic printing plate. It is preferable to obtain.
The developer is preferably an alkaline developer, and more preferably an alkaline aqueous solution substantially free of an organic solvent.
Moreover, the developing solution which does not contain alkali metal silicate substantially is also preferable. As a method of developing using a developer substantially not containing an alkali metal silicate, a method described in detail in JP-A No. 11-109637 can be used.
A developer containing an alkali metal silicate can also be used.

When the image recording layer is an unprocessed type, the lithographic printing plate precursor according to the present invention is mounted on a printing machine without any further processing after image exposure, and is usually used with ink and / or fountain solution. Can be printed with the procedure. Further, as described in Japanese Patent No. 2938398, after being mounted on a printing machine cylinder, it is exposed by a laser mounted on the printing machine, and then ink and / or fountain solution is applied to perform on-machine development. It is also possible to do. In these cases, since the heat-sensitive layer is removed by ink and / or fountain solution on the printing press, a separate development step is not required, and it is not necessary to stop the printing press for printing after development. Printing can be continued as soon as development is completed.
Even in the case of having an untreated type heat-sensitive layer, it can be used for printing after developing with water or an appropriate aqueous solution as a developer.

1. Production of support for lithographic printing plate (Example 1)
<Aluminum plate>
Si: 0.06 mass%, Fe: 0.30 mass%, Cu: 0.235 mass%, Mn: 0.001 mass%, Mg: 0.001 mass%, Zn: 0.001 mass%, Ti: It contains 0.03% by mass, and the balance is prepared using Al and an inevitable impurity aluminum alloy. Created. After the surface was shaved with a chamfering machine with an average thickness of 10 mm, it was kept soaked at 550 ° C. for about 5 hours, and when the temperature dropped to 400 ° C., rolling with a thickness of 2.7 mm using a hot rolling mill A board was used. Furthermore, after performing heat processing using a continuous annealing machine at 500 degreeC, it finished by cold rolling to 0.24 mm in thickness, and obtained the aluminum plate of JIS1050 material. After making this aluminum plate width 1030mm, it used for the surface treatment shown below.

<Surface treatment>
The surface treatment was performed by continuously performing the following various treatments (a) to (l). In addition, after each process and water washing, the liquid was drained with the nip roller.

(A) Mechanical surface roughening treatment Using an apparatus as shown in FIG. 1, a suspension of a polishing agent (pumice) having a specific gravity of 1.12 and water is supplied as a polishing slurry to the surface of the aluminum plate. However, a mechanical surface roughening treatment was performed with a rotating roller-like nylon brush. In FIG. 1, 1 is an aluminum plate, 2 and 4 are roller brushes, 3 is a polishing slurry, and 5, 6, 7 and 8 are support rollers. The average particle size of the abrasive was 40 μm, and the maximum particle size was 100 μm. The material of the nylon brush was 6 · 10 nylon, the hair length was 50 mm, and the hair diameter was 0.3 mm. The nylon brush was planted so as to be dense by making a hole in a stainless steel tube having a diameter of 300 mm. Three rotating brushes were used. The distance between the two support rollers (φ200 mm) at the bottom of the brush was 300 mm. The brush roller was pressed until the load of the drive motor for rotating the brush became 7 kW plus with respect to the load before the brush roller was pressed against the aluminum plate. The rotating direction of the brush was the same as the moving direction of the aluminum plate. The rotation speed of the brush was 200 rpm.

(B) Alkali etching treatment The aluminum plate obtained above is subjected to an etching treatment by spraying using an aqueous solution having a caustic soda concentration of 2.6 mass%, an aluminum ion concentration of 6.5 mass%, and a temperature of 70 ° C. / M ² dissolved. Then, water washing by spraying was performed.

(C) Desmutting treatment The desmutting treatment was performed by spraying with a 1% by mass aqueous solution of nitric acid at a temperature of 30 ° C. (containing 0.5% by mass of aluminum ions), and then washed with water by spraying. The nitric acid aqueous solution used for the desmut treatment was a waste liquid from a process of performing an electrochemical surface roughening treatment using alternating current in a nitric acid aqueous solution.

(D) Electrochemical roughening treatment An electrochemical roughening treatment was carried out continuously using an alternating voltage of 60 Hz. The electrolytic solution at this time was a 10.5 g / L aqueous solution of nitric acid (containing 5 g / L of aluminum ions and 0.007% by mass of ammonium ions) at a liquid temperature of 50 ° C. The AC power supply waveform is the waveform shown in FIG. 2, the time TP until the current value reaches the peak from zero is 0.8 msec, the duty ratio is 1: 1, a trapezoidal rectangular wave AC is used with the carbon electrode as the counter electrode An electrochemical roughening treatment was performed. Ferrite was used for the auxiliary anode. The electrolytic cell used was the one shown in FIG.
The current density was 30 A / dm ² at the peak current value, and the amount of electricity was 220 C / dm ² in terms of the total amount of electricity when the aluminum plate was the anode. 5% of the current flowing from the power source was shunted to the auxiliary anode.
Then, water washing by spraying was performed.

(E) Alkali etching treatment An aluminum plate was sprayed at 32 ° C. using an aqueous solution having a caustic soda concentration of 26% by mass and an aluminum ion concentration of 6.5% by mass to dissolve the aluminum plate by 1.0 g / m ² . Removes the smut component mainly composed of aluminum hydroxide generated when electrochemical surface roughening treatment was performed using alternating current in the previous stage, and also melted the edge part of the generated pit to smooth the edge part. did. Then, water washing by spraying was performed.

(F) Desmut treatment Desmut treatment by spraying was performed with a 15% by weight aqueous solution of sulfuric acid at a temperature of 30 ° C. (containing 4.5% by weight of aluminum ions), and then washed with water by spraying. The nitric acid aqueous solution used for the desmut treatment was a waste liquid from a process of performing an electrochemical surface roughening treatment using alternating current in a nitric acid aqueous solution.

(G) Electrochemical surface roughening treatment An electrochemical surface roughening treatment was performed continuously using an alternating voltage of 60 Hz. The electrolytic solution at this time was a hydrochloric acid 7.5 g / L aqueous solution (containing 5 g / L of aluminum ions) at a temperature of 35 ° C. The AC power supply waveform is the waveform shown in FIG. 2, the time TP until the current value reaches the peak from zero is 0.8 msec, the duty ratio is 1: 1, a trapezoidal rectangular wave AC is used with the carbon electrode as the counter electrode An electrochemical roughening treatment was performed. Ferrite was used for the auxiliary anode. The electrolytic cell used was the one shown in FIG.
The current density was 25 A / dm ² at the peak current value, and the amount of electricity was 50 C / dm ² in terms of the total amount of electricity when the aluminum plate was the anode.
Then, water washing by spraying was performed.

(H) Alkaline etching treatment The aluminum plate was subjected to an etching treatment at 32 ° C. using an aqueous solution having a caustic soda concentration of 26 mass% and an aluminum ion concentration of 6.5 mass%, and the aluminum plate was dissolved by 0.2 g / m ² . Removes the smut component mainly composed of aluminum hydroxide generated when electrochemical surface roughening treatment was performed using alternating current in the previous stage, and also melted the edge part of the generated pit to smooth the edge part. did. Then, water washing by spraying was performed.

(I) Desmutting treatment A desmutting treatment by spraying was performed with a 25% by weight aqueous solution of sulfuric acid at a temperature of 60 ° C. (containing 0.5% by weight of aluminum ions), followed by washing with water by spraying.

(J) Anodizing treatment Anodizing treatment was performed using an anodizing apparatus having a structure shown in FIG. Sulfuric acid was used as the electrolytic solution supplied to the first and second electrolysis units. All electrolytes had a sulfuric acid concentration of 170 g / L (containing 0.5 mass% of aluminum ions) and a temperature of 38 ° C. Then, water washing by spraying was performed. The final oxide film amount was 2.7 g / m ² .

(K) Sealing treatment Next, sealing treatment was performed. The sealing treatment was performed by sealing an aqueous solution (liquid temperature 75 ° C.) containing 0.1% by mass of sodium zirconate fluoride (Na ₂ ZrF ₆ ) and 1% by mass of sodium dihydrogen phosphate (NaH ₂ PO ₄ ). It was used by immersing an aluminum plate in this sealing treatment solution for 10 seconds. Then, water washing by spraying was performed.

(L) Hydrophilization treatment Next, the hydrophilic treatment was performed. The hydrophilization treatment was performed by immersing the aluminum plate in a 1% by mass aqueous sodium silicate solution (liquid temperature 50 ° C.) for 10 seconds.
The amount of Si on the aluminum surface measured with a fluorescent X-ray analyzer was 0.8 mg / m ² . Thereafter, washing with water was performed to obtain a lithographic printing plate support.

(Example 2)
A lithographic printing plate support was obtained in the same manner as in Example 1 except that the etching amount in the alkali etching treatment (h) was 0.4 g / m ² .
(Example 3)
A lithographic printing plate support was obtained in the same manner as in Example 1 except that the etching amount in the alkali etching treatment (h) was 0.1 g / m ² .
(Examples 4-9 and Comparative Examples 4-6)
Each lithographic printing plate support was obtained in the same manner as in Example 1 except that the sealing treatment liquid, the liquid temperature, and the treatment time in the (k) sealing treatment were changed as shown in Table 1. .
(Comparative Example 1)
A lithographic printing plate support was obtained in the same manner as in Example 1 except that the etching amount in the alkali etching treatment (h) was 0.6 g / m ² .
(Comparative Example 2)
A lithographic printing plate support was obtained in the same manner as in Example 1 except that the etching amount in the alkali etching treatment (h) was 0.03 g / m ² .
(Comparative Example 3)
Each lithographic printing plate support was obtained in the same manner as in Example 1 except that (k) the sealing treatment was not performed.

(Comparative Example 7)
Instead of the above (k) sealing treatment, it was immersed in a 0.5% by mass potassium fluoride zirconate aqueous solution (liquid temperature 20 ° C.) for 60 seconds, then washed with water and then 1.2% by mass. For each lithographic printing plate in the same manner as in Example 1 except that it was immersed in an aqueous solution of potassium dihydrogen phosphate (liquid temperature 20 ° C.) for 60 seconds, washed with water by spraying, and sealed. A support was obtained.
(Comparative Example 8)
Instead of the above (k) sealing treatment, the substrate was immersed in a 0.5% by mass potassium fluoride zirconate aqueous solution (liquid temperature 20 ° C.) for 80 seconds, washed with water, and then 0.8% by mass. Each lithographic printing was carried out in the same manner as in Example 1 except that it was immersed in an aqueous solution of potassium dihydrogen phosphate (liquid temperature 0.5 ° C.) for 70 seconds, washed with water by spraying, and sealed. A plate support was obtained.

(Examples 10 and 13 to 16 and Comparative Examples 11 and 12)
Each lithographic printing plate support was obtained in the same manner as in Example 1 except that the sealing treatment liquid, the liquid temperature and the treatment time in the above (k) sealing treatment were changed as shown in Table 2. .
(Example 11)
A lithographic printing plate support was obtained in the same manner as in Example 2 except that the liquid temperature and treatment time in the (k) sealing treatment were changed as shown in Table 2.
(Example 12)
A lithographic printing plate support was obtained in the same manner as in Example 3, except that the liquid temperature and the treatment time in the (k) sealing treatment were changed as shown in Table 2.
(Comparative Example 9)
A lithographic printing plate support was obtained in the same manner as in Comparative Example 1 except that the liquid temperature and the treatment time in the (k) sealing treatment were changed as shown in Table 2.
(Comparative Example 10)
A lithographic printing plate support was obtained in the same manner as in Comparative Example 2, except that the liquid temperature and treatment time in the (k) sealing treatment were changed as shown in Table 2.

2. Surface shape of lithographic printing plate support The average opening diameter (small pit diameter) of pits having a small wave structure was determined as follows on the surface of the lithographic printing plate support obtained above.
The surface of the lithographic printing plate support was scanned using a scanning electron microscope (S-900, manufactured by Hitachi, Ltd.) at a magnification of 100,000, and 50 small-wave pit opening diameters were obtained. Was measured and the average was determined.
The results are shown in Tables 1 and 2.

3. Element amounts on the surface of the lithographic printing plate support The amounts of zirconium, phosphorus, sodium and silicon on the surfaces of the lithographic printing plate supports obtained in Examples 1 to 9 and Comparative Examples 1 to 8 were measured with fluorescent X-rays. Measurement was performed by a calibration curve method using an analyzer. The results are shown in Table 1.
As a standard sample for preparing a calibration curve, an aqueous solution containing a known amount of any one of a zirconium atom, a phosphorus atom, a sodium atom and a silicon atom is uniformly dropped into an area of 30 mmφ on an aluminum plate. Then, the dried one was used. The conditions for fluorescent X-ray analysis are shown below.

<Zirconium amount>
X-ray fluorescence analyzer: RIX3000 manufactured by Rigaku Corporation, X-ray tube: Rh, measurement spectrum: Zr-Kα, tube voltage: 50 kV, tube current: 50 mA, slit: COARSE, spectral crystal: LIF1, detector: SC , Analysis area: 30 mmφ, peak position (2θ): 22.54 deg. , Background (2θ): 21.94 deg. And 23.14 deg. , Integration time: 20 seconds / sample

<Phosphorus amount>
X-ray fluorescence analyzer: RIX3000 manufactured by Rigaku Corporation, X-ray tube: Rh, measurement spectrum: P-Kα, tube voltage: 50 kV, tube current: 50 mA, slit: COARSE, spectral crystal: GE, detector: PC , Analysis area: 30 mmφ, peak position (2θ): 141.18 deg. , Background (2θ): 139.18 deg. And 143.18 deg. , Integration time: 40 seconds / sample

<Sodium amount>
X-ray fluorescence analyzer: RIX3000 manufactured by Rigaku Corporation, X-ray tube: Rh, measurement spectrum: Na-Kα, tube voltage: 50 kV, tube current: 50 mA, slit: COARSE, spectral crystal: TAP, detector: PC , Analysis area: 30 mmφ, peak position (2θ): 55.2 deg. , Background (2θ): 53 deg. And 57 deg. Integration time: 80 seconds / sample

<Amount of silicon>
X-ray fluorescence analyzer: RIX3000 manufactured by Rigaku Corporation, X-ray tube: Rh, measurement spectrum: Si-Kα, tube voltage: 50 kV, tube current: 50 mA, slit: COARSE, spectral crystal: RX4, detector: F -PC, analysis area: 30 mmφ, peak position (2θ): 144.75 deg. , Background (2θ): 140.70 deg. And 146.85 deg. Integration time: 80 seconds / sample

4). Measurement of surface of lithographic printing plate support by X-ray photoelectron spectroscopy The surface of the lithographic printing plate support obtained in Examples 10 to 16 and Comparative Examples 3 and 7 to 12 was subjected to X-ray photoelectron spectroscopy (ESCA). ) The conditions of ESCA are shown below.
Apparatus: ESCA PHI-5400MC, ULVAC-PHI, Inc. X-ray source: Mg-Kα (400 W)
Pulse energy: 71.55 eV / 178.95 eV
take off angle: 45 degrees

The peak areas of the obtained fluorine (1s), zirconium (3d), phosphorus (2p) and aluminum (2p) are shown in Table 2 as A, B, C and D, respectively.
Moreover, the value of (A + B + C) / (A + B + C + D) in the above formula (1) was calculated. The results are shown in Table 2.

5). Preparation of a lithographic printing plate precursor A coating solution for an image recording layer having the following composition was applied to each of the lithographic printing plate supports obtained above and dried in an oven at 60 ° C for 150 seconds to obtain a lithographic printing plate precursor. Obtained. The dry coating amount of the image recording layer was 0.7 g / m ² .

<Coating solution composition for image recording layer>
・ Microcapsule solution 5g (solid content) to be described later
・ Trimethylolpropane triacrylate 3g
-Photothermal conversion agent represented by the following formula 0.3 g
・ Water 60g
・ 1-methoxy-2-propanol 40g

<Preparation of microcapsules>
40 g of xylene diisocyanate, 10 g of trimethylolpropane diacrylate, 10 g of a copolymer of allyl methacrylate and butyl methacrylate (molar ratio 7/3) and 0.1 g of a surfactant (Pionin A41C, manufactured by Takemoto Yushi Co., Ltd.) are dissolved in 60 g of ethyl acetate. To obtain an oil phase component. On the other hand, 120 g of a 4% aqueous solution of polyvinyl alcohol (PVA205, manufactured by Kuraray Co., Ltd.) was prepared and used as an aqueous phase component. The oil phase component and the aqueous phase component were charged into a homogenizer and emulsified using 10,000 rpm. Thereafter, 40 g of water was added, stirred at room temperature for 30 minutes, and further stirred at 40 ° C. for 3 hours to obtain a microcapsule solution. The obtained microcapsule liquid had a solid content concentration of 20% by mass, and the average particle size of the microcapsules was 0.2 μm.

6). Sensitivity of Planographic Printing Plate Precursor The lithographic printing plate precursor obtained above was output and exposed under the conditions of a resolution of 2400 dpi using a Luxel T-9000CTP manufactured by Fuji Photo Film Co., Ltd. equipped with a multichannel laser head. At this time, the output per beam and the rotation speed of the outer drum were changed, and the sensitivity was evaluated based on the minimum exposure amount capable of forming an image. The results are shown in Tables 1 and 2.

7). Printing test After the lithographic printing plate precursor obtained above was exposed as described above (exposure amount 150 mJ / cm ² ), it was attached to a cylinder of a printing machine SOR-M manufactured by Heidelberg without any treatment. After supplying water, ink was supplied, and paper was further supplied for a printing test. In all of the planographic printing plate precursors of the examples, on-press development was possible without problems and printing was possible.
In the above printing test, the entanglement of the mesh portion and the printing durability were evaluated by the following methods.

(1) Intertwining of net part In the image of the net part of the printed matter (halftone dot area ratio 70 to 80%), it was observed visually whether ink entanglement occurred and the entanglement of the net part was evaluated.
The results are shown in Tables 1 and 2. In the table, the case where no ink entanglement occurred in the mesh portion was indicated by ○, and the case where the ink occurred was indicated by ×.

(2) Printing durability The printing durability was evaluated based on the number of printed sheets when it was visually recognized that the density of the solid image of the printed material began to decrease.
The results are shown in Tables 1 and 2.

As is apparent from Table 1, the lithographic printing plate precursors (Examples 1 to 9) using the lithographic printing plate support according to the first aspect of the present invention have sensitivity, entanglement of the net portion, and printing durability. Both are excellent.
In contrast, when the small pit diameter is too large (Comparative Example 1), the amount of phosphorus on the surface is too large (Comparative Example 5), and the amount of zirconium on the surface is too large (Comparative Example 6), the printing durability is increased. Inferior to Further, when the small pit diameter is too small (Comparative Example 2) and when either the amount of zirconium or the amount of phosphorus is too small (Comparative Examples 3, 4, 7, and 8), the entanglement of the net is inferior.

Further, as is apparent from Table 2, the lithographic printing plate precursors (Examples 10 to 16) using the lithographic printing plate support of the second aspect of the present invention had sensitivity, entanglement of halftone and printing durability. Excellent in both sex.
In contrast, when the small pit diameter is too large (Comparative Example 9) and when (A + B + C) / (A + B + C + D) in the above formula (1) is too large (Comparative Example 12), the printing durability is poor. Further, when the small pit diameter is too small (Comparative Example 10), when (A + B + C) / (A + B + C + D) in the above formula (1) is too small (Comparative Examples 3 and 11) and C in the above formula (2) is When it is too small (Comparative Examples 7 and 8), the mesh portion is inferior.

It is a side view which shows the concept of the process of the brush graining used for the mechanical roughening process in preparation of the support body for lithographic printing plates of this invention. It is a graph which shows an example of the alternating waveform current waveform figure used for the electrochemical roughening process in preparation of the support body for lithographic printing plates of this invention. It is a side view which shows an example of the radial type cell in the electrochemical roughening process using alternating current in preparation of the support body for lithographic printing plates of this invention. It is the schematic of the anodizing apparatus used for the anodizing process in preparation of the support body for lithographic printing plates of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Aluminum plate 2, 4 Roller-shaped brush 3 Polishing slurry liquid 5, 6, 7, 8 Support roller 11 Aluminum plate 12 Radial drum roller 13a, 13b Main electrode 14 Electrolytic process liquid 15 Electrolyte supply port 16 Slit 17 Electrolyte path 18 Auxiliary anodes 19a, 19b Thyristors 20 AC power supply 40 Main electrolytic tank 50 Auxiliary anode tank 410 Anodizing device 412 Power supply tank 414 Electrolytic treatment tank 416 Aluminum plate 418, 426 Electrolytic solution 420 Power supply electrode 422, 428 Roller 424 Nip roller 430 Electrolytic electrode 432 Tank wall 434 DC power supply

Claims (6)

It has a small wave structure consisting of pits having an average opening diameter of 0.02 to 0.2 μm on the surface, the amount of zirconium on the surface is 0.5 to 30 mg / m ² , and the amount of phosphorus on the surface is ² to 30 mg / m ² A support for a lithographic printing plate. The lithographic printing plate support according to claim 1, wherein the amount of sodium on the surface is 1.0 mg / m ² or more and the amount of silicon on the surface is 0.1 to 3 mg / m ² . A lithographic printing plate support having a small wave structure comprising pits having an average opening diameter of 0.02 to 0.2 μm on the surface, the surface satisfying the following formulas (1) and (2).
0.10 ≦ (A + B + C) / (A + B + C + D) ≦ 0.90 (1)
C> 1.0 (2)
A: Peak area (counts · eV / sec) of fluorine (1s) obtained by measurement using X-ray photoelectron spectroscopy
B: Peak area of zirconium (3d) obtained by measurement using X-ray photoelectron spectroscopy (counts · eV / sec)
C: Phosphorus (2p) peak area (counts · eV / sec) obtained by measurement using X-ray photoelectron spectroscopy
D: Peak area of aluminum (2p) obtained by measurement using X-ray photoelectron spectroscopy (counts · eV / sec)   The aluminum plate is obtained by subjecting the aluminum plate to treatment with an aqueous solution containing at least an inorganic fluorine compound and a phosphate compound, and then further treating with an aqueous solution containing an alkali metal silicate. The support for a lithographic printing plate according to any one of -3.   A lithographic printing plate precursor comprising an image recording layer provided on the lithographic printing plate support according to any one of claims 1 to 4.   The lithographic printing plate precursor as claimed in claim 5, wherein the image recording layer is an image recording layer writable by infrared laser exposure.

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