JPH09304938A - Aluminum support body for lithography printing plate and photosensitive lithography printing plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aluminum support body for lithography printing plate and a photosensitive lithography printing plate which provide good development property and do not make a blanket dirty. SOLUTION: In an aluminum support body on which rough surface and positive pole oxidation treatment is applied, a pit structure of a recessed pit on a rough surface has secondary structure or more, an upper projection area ratio of a pit having the maximum degree for apparent area is 0.7 or more, and average diameter of a pit opening of the recessed pit on the rough surface is 1.0μm or less. The rough surface has the recessed pit, and a ratio of the primary pit which is not contained in the secondary pit or more and exists singly for the whole primary pit is 80% or more. The rough surface has the recessed pit, and an upper projection area ratio of the primary pit which is not contained in the secondary pit or more and exists singly for apparent area is 0.5 or more. Radius of curvature of 70% or more of a part sandwiched by the recessed pits having a diameter of opening of 0.5μm or more after alkali etching conforms to the following equation.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an aluminum support used for a lithographic printing plate and a photosensitive lithographic printing plate using the support.

[0002]

BACKGROUND OF THE INVENTION A photosensitive lithographic printing plate is a positive lithographic printing plate having a photosensitive layer provided on a support, and a positive photosensitive composition layer provided on the support. There is a negative-working photosensitive lithographic printing plate having a negative-working photosensitive composition layer provided thereon.

Conventionally, the support of these photosensitive lithographic printing plates has excellent hydrophilicity and water retention from the viewpoint of printability,
Moreover, it is required to have excellent adhesiveness to the photosensitive layer, and an aluminum plate is usually used, and a roughening treatment called graining is performed.

For the surface roughening treatment, mechanical surface roughening methods such as ball polishing, brush polishing, blast polishing, buff polishing, honing polishing, etc., and the surface of the support by AC or DC in an acidic electrolytic solution such as hydrochloric acid or nitric acid. Electrochemical surface-roughening methods for electrolytically treating, or chemical surface-roughening methods, methods combining these surface-roughening methods, and the like are used.

The aluminum plate which has been grained by these methods has a soft surface and is easily worn as it is. Therefore, it is anodized to form a hard oxide film on the surface to obtain wear resistance.

In the above graining treatment, the surface of the grained grained support is further treated, or the rough surface shape of the support is specified to further improve the performance of the photosensitive lithographic printing plate. Is being attempted.

For example, it has been proposed to improve the performance of the photosensitive lithographic printing plate by subjecting it to an anodizing treatment followed by a hydrophilizing treatment. For example, JP-A-56-21126 discloses a hydrophilic resin. And a method of providing an undercoat layer consisting of a water-soluble salt, JP-A-64-14090, a method of providing an undercoat layer consisting of a carboxylate, JP-A-63-130391,
A method of providing a hydrophilic layer composed of at least one selected from an inorganic acid salt and an organic acid salt of a compound having at least one amino group and at least one group selected from a carboxyl group and a sulfo group is disclosed in Japanese Patent Application Laid-Open No. 63-165183 proposes a method of providing a hydrophilic layer containing at least one amino group and a phosphon group or a salt of a phosphon group. In addition, a method of removing a residue (smut) of impurities in aluminum generated on the surface of an aluminum plate subjected to an electrochemical surface roughening treatment and a treatment unevenness has been proposed.
JP-A-53-12739 discloses that the surface of a roughened aluminum plate is brought into contact with a sulfuric acid solution at 50 to 90 ° C. to dissolve and remove smut, and JP-B-48-28135 discloses. It has been proposed that an aluminum plate electrochemically roughened in hydrochloric acid is lightly etched in an alkaline aqueous solution. Further, Japanese Patent Publication No. 2-12752 proposes electrolytically roughening a surface in a nitric acid-based electrolytic solution and then performing alkali etching.

It has also been proposed to improve the performance of the photosensitive lithographic printing plate by making the surface of the support have a specific rough surface shape, for example, US Pat. No. 4,301,229.
In the specification, the cumulative frequency distribution of the pit diameter formed on the surface of the support and the centerline average roughness are specified.
U.S. Pat.No. 3,861,917 describes that the depth of the rough surface of the support is specified in Canadian Patent 955,44.
In the specification of No. 9, it is specified that the height and diameter of the peaks of the rough surface of the support surface are specified, and in the specification of German Patent 1,813,443, the height difference of the rough surface of the support surface is specified. In JP-A-55-132294, it is specified that the average depth of pits formed on the surface of the support is specified, and in JP-A-5-24376, the support is It has been proposed that the pit diameter formed on the surface and the maximum depth in the direction perpendicular to the pit diameter be specified.

However, even if the grained surface of the support is further treated or the surface roughness of the support is specified, the performance of the photosensitive lithographic printing plate is Improvement was inadequate.

Then, the present inventors further examined the relationship between the pit structure of the rough surface of the support and the printing durability and stain resistance, and found that the pit structure of the concave pit of the rough surface of the support was
There is a pit structure of secondary or more, and by using a support having a rough surface having an upper projected area ratio of pits of maximum order to the apparent area of 0.7 or more, printing durability of the photosensitive lithographic printing plate, It has been found that the stain resistance is improved. In addition, when the relationship between the shape of the concave pits on the surface of the support and the small point reproducibility, K value, and stain resistance was examined,
(A) Determine the average diameter of the openings of the concave pits on the rough surface of the support.
The ratio of the primary pits that exist independently to the total of the primary pits on the rough surface of the support (b) that is 1.0 μm or less.
80% or more of the support, (c) to the apparent area,
A support having an upper projected area ratio of 0.5 or more of primary pits which are not included in secondary pits or more and exist independently, (d) "pit diameter" and "maximum depth in a direction perpendicular to the diameter" of primary pits It has been found that the use of a support having a linear gradient of 0.3 or more by linear regression analysis improves the dot reproducibility, K value, and stain resistance. Further, electrochemical roughening treatment, alkali etching treatment, anodizing treatment of the aluminum support rough surface shape and developability,
When the relationship between non-image area dirt, blanket dirt, printing durability, and dirt resistance was examined, a sharp edge formed by pits with an opening diameter of 0.5 μm or more formed by electrochemical graining Part is dissolved by alkali etching,
A support in which the shape of the sharp portion of 70% or more has a radius of curvature that falls within a specific radius of curvature calculated from the average depth in the direction perpendicular to the pit diameter and the average diameter of the pit opening. In addition to the support, a measuring length of 0.5 mm
1 μm from the top of the 3rd highest mountain of the three-dimensional surface roughness curve
The total area of the figure formed by the reference line drawn below in parallel with the center line of roughness and the roughness curve above the reference line is
By using a support having a 50 [mu] m ² or more 150 [mu] m ² or less, developability becomes excellent, dirt blanket hardly occurs, and it has been found that excellent printing durability and stain resistance can be obtained.

[0011]

OBJECT OF THE INVENTION The first object of the present invention is to provide an aluminum support for a lithographic printing plate which has both printing durability and stain resistance.

A second object of the present invention is the small point reproducibility and K
An object is to provide an aluminum support for a lithographic printing plate that has excellent values and is resistant to stains.

A third object of the present invention is to provide an aluminum support for a lithographic printing plate which has both printing durability and stain resistance, has good developability, and is less likely to cause blanket stains.

A fourth object of the present invention is to provide a photosensitive lithographic printing plate which has both printing durability and stain resistance, a photosensitive lithographic printing plate which is excellent in small point reproducibility and K value, and is hard to stain, and printing durability. It is intended to provide a photosensitive lithographic printing plate which has both excellent property and stain resistance, has good developability, and is less likely to cause blanket stain.

[0015]

The first object of the present invention is as follows. (1) In an aluminum support which has been roughened and anodized, the pit structure of the concave pits on the rough surface is a pit structure of secondary or higher pit structure. And an upper projected area ratio of the maximum-order pits to the apparent area is 0.7 or more, an aluminum support for a lithographic printing plate.

The second object of the present invention is: (2) In a roughened and anodized aluminum support, the rough surface has concave pits, and the pit opening of the concave pits. An aluminum support for a lithographic printing plate, which has an average diameter of 1.0 μm or less. (3) In the aluminum support that has been roughened and anodized, the rough surface has concave pits, and the "pit diameter" of the primary pit and the maximum depth in the direction perpendicular to the diameter. The linear support according to the first-order regression analysis has a slope of 0.3 or more, and the aluminum support for a lithographic printing plate as described in (2) above. (4) In an aluminum support that has been roughened and anodized, the rough pits have concave pits, and the primary pits are not included in the pits of the secondary primaries or more and are present independently of the entire primary pits. Is 80% or more, and an aluminum support for a lithographic printing plate. (5) In an aluminum support that has been roughened and anodized, the rough surface has concave pits, and the primary pits that are not included in the pits of the second or higher size and are present independently of the apparent area. An aluminum support for a lithographic printing plate, characterized in that the upper projected area ratio of the above is 0.5 or more.

The third object of the present invention is: (6) In an aluminum support which has been roughened and anodized, the opening diameter in the concave pits formed by electrochemical roughening The sharp part that can be confirmed by observing from the cross section the part formed by being sandwiched by pits of 0.5 μm or more is dissolved by alkali etching, and after alkali etching, the part sandwiched by concave pits with an opening diameter of 0.5 μm or more And 70% or more of the curvature is calculated by the following formula 1 from the average depth of the concave pits formed by electrochemical surface roughening in the direction perpendicular to the pit diameter and the average diameter of the pit openings. An aluminum support for a lithographic printing plate, which has a radius.

[0018]

[Equation 2] (7) In an aluminum support that has been roughened and anodized, the roughness is measured 1 μm below the apex of the third highest peak of the two-dimensional surface roughness curve with a measurement length of 0.5 mm on the surface of the support. The total area of a figure formed by a reference straight line drawn parallel to the center line and a roughness curve above the reference straight line is 50 μm ² or more and 150 μm ² or less, (6) described above. Aluminum support for lithographic printing plates. (8) A photosensitive lithographic printing plate comprising a layer of a photosensitive composition provided on the aluminum support for a lithographic printing plate according to any one of (1) to (7) above. Achieved by

Hereinafter, the present invention will be described in detail.

The aluminum support used in the present invention includes a support made of pure aluminum and an aluminum alloy. Various aluminum alloys can be used, for example, silicon, copper, manganese, magnesium, chromium, zinc, lead, bismuth, nickel, titanium,
An alloy of aluminum with a metal such as sodium or iron is used.

The aluminum support is preferably subjected to a degreasing treatment in order to remove rolling oil and the like on the aluminum surface prior to roughening. As the degreasing treatment, trichlene,
A degreasing treatment using a solvent such as thinner, an emulsion degreasing treatment using an emulsion such as kerosene or triethanol, and the like are used. In addition, an alkaline aqueous solution such as caustic soda can be used for the degreasing treatment. When an alkaline aqueous solution such as caustic soda is used for the degreasing treatment, dirt and oxide film that cannot be removed by the above degreasing treatment alone can also be removed.

When an alkaline aqueous solution such as caustic soda is used for the degreasing treatment, it is preferable to immerse it in an acid such as phosphoric acid, nitric acid, sulfuric acid, chromic acid or a mixed acid thereof to carry out the neutralization treatment.

As the surface roughening of the support, mechanical surface roughening, electrochemical surface roughening, or a combination of mechanical surface roughening and electrochemical surface roughening can be performed. .

The mechanical surface roughening method is not particularly limited, but brush polishing and honing polishing are preferable.

In the brush polishing, for example, a cylindrical brush having bristles having a bristle diameter of 0.2 to 1 mm is planted is rotated, and a slurry in which an abrasive is dispersed in water is supplied to the contact surface,
The surface is roughened by pressing it against the surface of the support. In the honing polishing, for example, a slurry in which an abrasive is dispersed in water is ejected by applying pressure from a nozzle and colliding obliquely with the surface of a support to roughen the surface.

As the abrasive, granite, alundum,
Silica, diatomaceous earth, soil, sand, hard sand, garnet, talc, pumice, dolomite, magnesium oxide, alumina, zirconia, SUS, iron powder, tungsten carbide, etc. are used, and the particle size is preferably # 20 to # 4000, # Ten
0 to # 1000 is more preferable.

The mechanically roughened support is dipped in an aqueous solution of acid or alkali in order to remove abrasives, aluminum debris, etc., which have invaded the surface of the support, and to control the pit shape. It is preferable to etch the surface. Examples of the acid include sulfuric acid, persulfuric acid,
Hydrofluoric acid, phosphoric acid, nitric acid, hydrochloric acid and the like are included, and examples of the base include sodium hydroxide, potassium hydroxide and the like. Among these, it is preferable to use an aqueous alkali solution.

When the above-mentioned etching treatment is carried out by dipping treatment in an aqueous alkali solution, it is preferable to carry out the neutralization treatment by dipping in an acid such as phosphoric acid, nitric acid, sulfuric acid, chromic acid or a mixed acid thereof.

The electrochemical surface roughening is generally carried out by using an alternating current in an acidic electrolytic solution. As the acidic electrolytic solution, one that is usually used in the electrochemical roughening method can be used,
In particular, it is preferable to use a hydrochloric acid-based or nitric acid-based electrolytic solution. For the electrochemical roughening method, see, for example,
48-28123, British Patent 896563, JP-A-53
The method described in JP-A-67507 can be used.

The voltage applied in the electrochemical graining is preferably 1 to 50 volts, more preferably 5 to 30 volts. The current density is preferably 10 to 200 A / dm ² , and 20 to 150 A / d.
m ² is more preferred. Further, it is also preferable to carry out at a high current density (100 to 200 A / dm ² ) for a short period of time in the initial stage. The amount of electricity is 100
~2000c / dm ^2, preferably 200~1500c / dm ^2, more preferably 200~1000c / dm ^2. The temperature is preferably from 10 to 50C, more preferably from 15 to 45C. The concentration of nitric acid and hydrochloric acid in the acidic electrolyte is preferably 0.05 to 5% by weight,
3% by weight is more preferred.

If necessary, nitrates, chlorides, amines, aldehydes, phosphoric acid, chromic acid, boric acid, acetic acid, oxalic acid and the like can be added to the electrolytic solution.

If necessary, nitrates, chlorides, amines, aldehydes, phosphoric acid, chromic acid, boric acid, acetic acid, oxalic acid and the like can be added to the electrolytic solution.

The electrochemically roughened support is preferably etched by immersing it in an acid or alkali aqueous solution in order to remove smut on the surface and control the pit shape. . As the acid,
For example, sulfuric acid, persulfuric acid, hydrofluoric acid, phosphoric acid, nitric acid, hydrochloric acid and the like are included, and examples of the alkali include sodium hydroxide, potassium hydroxide, potassium triphosphate, sodium aluminate, sodium metasilicate and the like. Among these, it is preferable to use an aqueous alkali solution.

Further, the alkali etching of the present invention (claims 6 and 7) is carried out by treating the alkali solution of 5 to 40% by weight at a liquid temperature of 20 to 90 ° C. for 1 to 60 seconds. be able to.

When the above is immersed in an aqueous alkali solution, it is preferably immersed in an acid such as phosphoric acid, nitric acid, sulfuric acid, chromic acid or a mixed acid thereof to carry out the neutralization treatment.

After the surface-roughening treatment, anodizing treatment is performed,
Subsequently, sealing treatment and hydrophilic treatment may be performed.

The method of anodic oxidation treatment used in the present invention is not particularly limited, and a known method can be used.
An oxide film is formed on the support by the anodic oxidation treatment. In the present invention, sulfuric acid and / or
Alternatively, an aqueous solution containing phosphoric acid or the like at a concentration of 10 to 50% is used as an electrolytic solution, and a method of electrolyzing at a current density of 1 to 10 A / dm ² is preferably used, but is also described in U.S. Pat.No. 1,412,768. A method of electrolyzing in sulfuric acid at a high current density, a method of electrolyzing using phosphoric acid described in US Pat. No. 3,511,661, and the like can be used.

The support which has been anodized may be subjected to a sealing treatment if necessary. These sealing treatments can be performed by using known methods such as hot water treatment, boiling water treatment, steam treatment, sodium silicate treatment, dichromate aqueous solution treatment, nitrite treatment and ammonium acetate treatment.

It is preferable that the support is further provided with a hydrophilic layer. For the formation of the hydrophilic layer, U.S. Pat.
Alkali metal silicates described in US Pat. No. 1,8
Hydrophilic cellulose described in JP 60,426 A, JP-A-60-1
49491, amino acids and salts thereof described in JP-A-63-165183, amines having a hydroxyl group and salts thereof described in JP-A-60-232998, and described in JP-A-62-19494 And the polymer compounds containing a monomer unit having a sulfo group described in JP-A-59-101651 can be used.

Furthermore, in order to prevent scratches on the photosensitive layer when the photosensitive lithographic printing plates are stacked, and to prevent the elution of the aluminum component into the developing solution during development, JP-A-50-1
51136, JP 57-63293, JP 60-73538
The treatment described in JP-A No. 61-67863, JP-A No. 6-35174 and the like can be performed by providing a protective layer on the back surface of the support.

In the present invention, the pit order of the pit structure of the concave pits is determined by observing the rough surface formed on the aluminum support with a high resolution scanning electron microscope capable of obtaining a magnification of 200 to 50,000 times. You can judge.

First, the smallest unit pit observed from an observation image of 10,000 to 50,000 times is a primary pit. A pit having a primary pit on its wall surface is a secondary pit. 1
If the secondary pit cannot be confirmed at 0,000 to 50,000 times,
Lower the observation magnification. 10% of the total number of primary pits in the observation area
When the above is present on the wall surface of the secondary pit, it is determined that the rough surface has the secondary pit structure. A pit having a secondary pit on its wall surface is a tertiary pit. If the tertiary pit cannot be confirmed, lower the observation magnification. When 10% or more of the total number of secondary pits in the observation area are present on the wall surface of the tertiary pit, it is determined that the rough surface has the tertiary pit structure. Similarly, the order of the rough surface pit structure is determined.

FIG. 1 illustrates the order of the pit structure and shows a cross section of an aluminum support. In FIG. 1, 1 is an aluminum support, 2 is a primary pit, and 3 is a secondary pit. The secondary pits 3 have 10% or more of the total number of the primary pits 2 on the wall surface.

In a pit formed by electrochemically roughening an aluminum plate, a sharp portion 11 is formed in the portion sandwiched between the pits as shown in FIG.

By the alkali etching, the sharp portion 1
1 changes to a smooth-shaped tip portion 12, and the tip portion 12 has a spherical surface 13. In the aluminum support for a lithographic printing plate of the present invention of one aspect, in the concave pits formed by electrochemical roughening, a portion formed by being sandwiched by pits having an opening diameter of 0.5 μm or more is cross-sectioned. When observed further, the sharp portion 11 that can be confirmed is dissolved by alkali etching and changes into a relatively smooth shape. As a result of observing a portion sandwiched by pits having an opening diameter of 0.5 μm or more after alkali etching from a cross section, That
70% or more is the spherical surface 13 and is calculated by the following formula 1 from the average depth of the concave pits formed by electrochemical roughening in the direction perpendicular to the pit diameter and the average diameter of the pit openings. The tip portion 12 is a spherical surface 13 having a radius of curvature.

[0046]

(Equation 3)

The average depth in the direction perpendicular to the pit diameter used to calculate the range of the radius of curvature and the average diameter of the pit openings are obtained by cutting the aluminum support and using a high-resolution scanning electron microscope for the cross section. It can be determined by observing, measuring the diameter of the pit opening and the maximum depth in the direction perpendicular to the diameter of each pit, and calculating the average value.

In the present invention, "the ratio of the maximum projected area of the uppermost pits to the apparent area", "the average diameter of the openings of the concave pits", and "the entire primary pits are not included in the pits of the secondary or higher order, The ratio of the primary pits that exist in the above "," the ratio of the upper projected area of the primary pits that are not included in the pits of the secondary or higher to the apparent area and exist independently "," the "pit diameter" and "perpendicular to the diameter of the primary pits""Maximum depth in various directions", "Slope of a straight line by linear regression analysis", "Center of roughness 1 μm below the third highest peak of the two-dimensional surface roughness curve with a measured surface length of 0.5 mm "The total area of the figure formed by the reference straight line drawn in parallel with the line and the roughness curve above the reference straight line" is obtained as follows.

<Ratio of upper projected area of maximum-order pits to apparent area> The observation surface of the aluminum support surface was randomly selected, and the average diameter of the maximum-order pits was photographed using a high-resolution scanning electron microscope. The total area of the projection surface obtained when the shape of the pit opening of the maximum order on the observation surface is projected on a surface parallel to the support by observing at a magnification and field number of 5 mm or more and 100 or more can be confirmed. Then, the ratio of the upper projected area of the pit having the maximum degree to the apparent area is calculated as follows.

[0050]

(Equation 4)

<Average Diameter of Openings of Concave Pits> The concave pits on the surface of the aluminum support have an average diameter of 5 mm or more on a photograph using a high resolution scanning electron microscope, and a magnification with which 100 or more can be confirmed. Observed in the number of fields of view, as shown in FIG. 3, the maximum length c of the opening of the concave pit was determined, and the maximum length c was obtained by cutting the concave pit along the plane orthogonal to the straight line. The maximum length d of the width of the opening of the concave pit is calculated, and the individual diameters of the openings of the concave pit are calculated by the following, and these are averaged on a randomly selected observation surface to calculate the diameter of the opening of the concave pit. The average diameter.

[0052]

(Equation 5)

<Ratio of primary pits independently present in secondary or higher pits to the entire primary pits> The observation surface of the aluminum support surface was randomly selected and a high resolution scanning electron microscope was used. The concave pits are observed at a magnification and field number such that the total number of primary pits is 200 or more, and the total number of primary pits is obtained. In addition, the total number of primary pits existing in pits having a secondary or higher pit structure is obtained, and the ratio (%) of the primary pits existing independently in the concave pits is calculated as follows.

[0054]

(Equation 6)

<Ratio of the projected area of the primary pits to the apparent area, which is not included in the pits of the secondary or higher and exists independently> The observation surface of the surface of the aluminum support was randomly selected, and a high resolution scanning electron microscope was used. Observe at a magnification and field number such that the total number of primary pits that are not included in the pits of secondary or higher and exist independently is 200 or more, and the shape of the opening of the primary pit on the observation surface is projected on a plane parallel to the support. Then, the total area of the projection planes obtained at that time is calculated, and the upper projection area ratio of the primary pits which are not included in the pits of the secondary or higher and exist independently, to the apparent area, is calculated as follows.

[0056]

(Equation 7)

<Slope of straight line by primary regression analysis of “pit diameter” of primary pit and “maximum depth in direction perpendicular to diameter”>
The "pit diameter" and the "maximum depth in the direction perpendicular to the diameter" can be obtained by observing the cross section of a support made of aluminum or its alloy that has been roughened or anodized.

The cross-sectional shape of the support can be observed, for example, as follows. First, a support piece is embedded in a resin, which is cut in a direction perpendicular to the surface of the support, and the cross section of the obtained support is mirror-polished. The observation of the pits is performed by taking a picture from the direction directly in front of the cross section with an ordinary electron microscope. The shooting magnification at this time is about 3000 to 50000 times,
Select so that the pit shape with a pit diameter of 1 μm can be easily observed.

In the present invention, the "pit diameter" and the "maximum depth in the direction perpendicular to the diameter" are obtained from electron micrographs taken from the direction directly in front of the cross section. The "pit diameter" is the linear distance from one edge of the pit indentation observed in the cross-sectional photograph to the other edge, and when the pit is not opened vertically to the surface of the aluminum material. , This straight line is not parallel to the plane of the aluminum fabric. Also, "maximum depth in the direction perpendicular to the diameter"
Is the depth up to the position where the depth of the above "pit diameter" in the direction perpendicular to the straight line is the maximum. Don't

The "pit diameter" and "maximum depth in the direction perpendicular to the diameter" referred to in the present invention are obtained from the electron micrograph taken from the direction directly in front of the above-mentioned cross section. "Maximum diameter" and "maximum depth in the direction perpendicular to the diameter"
Is different from In the present invention, "pit diameter"
And "maximum depth in the direction perpendicular to the diameter", in order to obtain the linear gradient by linear regression analysis, at least 20 pits are randomly selected, and "pit diameter" and "maximum in the direction perpendicular to the diameter are selected. It is necessary to seek "depth".

At this time, the pits observed on the cross section are measured without deviation, but the pits of secondary or higher order should not be measured.

After measuring at least 20 pits according to the above measuring method, the actual length of "pit diameter" is shown in the X-axis data and the actual length of "maximum depth in the direction perpendicular to the diameter" is shown in the Y-axis data. Then, the linear regression analysis is performed and the following linear expression is obtained.

(Maximum depth in the direction perpendicular to the diameter) = g × (pit diameter) + h g in the primary regression equation is the primary of “pit diameter” and “maximum depth in the direction perpendicular to the diameter” of the primary pit. It is the slope of a straight line obtained by regression analysis.

<Reference line drawn parallel to the center line of roughness 1 μm below the apex of the third highest peak of the two-dimensional surface roughness curve having a measurement length of 0.5 mm on the surface of the support and the reference line Total area of the figure formed by the above roughness curve (hereinafter referred to as the total area of the roughness curve of the present invention)> A surface roughness meter (Rank Taylor Hopson Taristep) is used for the roughness curve. And measure. 0.1 x 2.5 for measurement
A pyramidal stylus of μm was used, and the vertical magnification was 10000 times, the measurement length was 0.5 mm, the measurement speed was 0.0025 mm / s, the sampling frequency was 10 ms, and the filter cutoff was 8 Hz. Higher frequency components than 8 Hz were removed.

From the above roughness curve, select the third highest protrusion, draw a reference line A parallel to the center line of the roughness 1 μm below the apex of the protrusion, and extend above the reference line A and the reference line A. The total area of the figure formed by the roughness curve and the figure was calculated. Actually, the calculation is performed from the data captured digitally from the Taristep.

The photosensitive lithographic printing plate of the present invention can be obtained by forming a layer of a photosensitive composition on the aluminum support of the present invention.

The photosensitive composition forming the photosensitive layer of the photosensitive lithographic printing plate of the present invention is not particularly limited, and the photosensitive composition used in the photosensitive lithographic printing plate is usually used. it can. Examples of the photosensitive composition that can be used in the present invention include the following. 1) Photocrosslinkable photosensitive resin composition The photosensitive component in the photocrosslinkable photosensitive resin composition comprises a photosensitive resin having an unsaturated double bond in a molecule,
For example, U.S. Pat.Nos. 3,030,208 and 3,435,237
No. 3,622,320, etc., as a photosensitive group in the polymer main chain.

[0068]

Embedded image And polyvinyl cinnamate having a photosensitive group on the side chain of the polymer. 2) Photopolymerizable photosensitive resin composition A photopolymerizable composition containing an addition-polymerizable unsaturated compound, comprising a monomer having a double bond or a monomer having a double bond, and a polymer binder. Representative examples of such a composition are described in, for example, US Pat. Nos. 2,760,863 and 2,791,504.

Examples of the photopolymerizable composition include a composition containing methyl methacrylate, a composition containing methyl methacrylate and polymethyl methacrylate, a composition containing methyl methacrylate, polymethyl methacrylate and polyethylene glycol methacrylate monomers. , A photopolymerizable composition such as a composition containing methyl methacrylate, an alkyd resin and a polyethylene glycol dimethacrylate monomer.

The photopolymerization type photosensitive resin composition contains a photopolymerization initiator (eg, a photopolymerization initiator) usually known in this technical field.
Benzoin derivatives such as benzoin methyl ether, benzophenone derivatives such as benzophenone, thioxanthone derivatives, anthraquinone derivatives, acridone derivatives, etc.)
Is added. 3) Photosensitive composition containing diazo compound Preferred examples of the diazo compound used in the photosensitive composition include diazo resins represented by condensates of an aromatic diazonium salt with formaldehyde or acetaldehyde. Particularly preferably, a salt of a condensate of p-diazophenylamine with formaldehyde or acetaldehyde, for example, a reaction product of the above condensate with hexafluorophosphate, tetrafluoroborate, perchlorate or periodate. Diazo resin inorganic salts, and diazo resin organic salts, which are reaction products of the condensate and sulfonic acids described in US Pat. No. 3,300,309.

The diazo resin is preferably used with a binder. As such a binder, various polymer compounds can be used, and preferably, a polymer is disclosed in JP-A-54-98613.
Monomer having an aromatic hydroxyl group, for example, N- (4-hydroxyphenyl) acrylamide, N- (4-hydroxyphenyl) methacrylamide, o-, m- or p-hydroxystyrene , O
-, A copolymer of m- or p-hydroxyphenyl methacrylate and the like and another monomer, a hydroxyethyl acrylate unit or a hydroxyethyl methacrylate unit described in U.S. Pat.No. 4,123,276 as a main repeating unit Containing polymers, natural resins such as shellac, rosin, polyvinyl alcohol, U.S. Pat.
Examples thereof include linear polyurethane resins described in No. 1,257, phthalated resins of polyvinyl alcohol, epoxy resins which are condensates of bisphenol A and epichlorohydrin, and cellulose derivatives such as cellulose acetate and cellulose acetate phthalate. 4) Photosensitive composition containing o-quinonediazide compound The o-quinonediazide compound is a compound having an o-quinonediazide group in a molecule. Examples of the o-quinonediazide compound that can be used in the present invention include: o-Naphthoquinonediazide compounds, for example, ester compounds of o-naphthoquinonediazidesulfonic acid with phenols and polycondensation resins with aldehydes or ketones.

The phenols in the polycondensation resin with the above-mentioned phenols and aldehydes or ketones include, for example, phenol, o-cresol, m-cresol,
Examples include monohydric phenols such as p-cresol, 3,5-xylenol, carvacrol, and thymol; dihydric phenols such as catechol, resorcinol, and hydroquinone; and trihydric phenols such as pyrogallol and phloroglucin. As the aldehyde, for example, formaldehyde,
Examples include benzaldehyde, acetaldehyde, crotonaldehyde, furfural and the like. Preferred among these are formaldehyde and benzaldehyde. Examples of the ketone include acetone, methyl ethyl ketone, and the like.

Specific examples of polycondensation resins with phenols and aldehydes or ketones include phenol-formaldehyde resin, m-cresol-formaldehyde resin, m- and p-mixed cresol-formaldehyde resin, resorcin-benzaldehyde resin, Examples include pyrogallol / acetone resin.

In the o-naphthoquinonediazide compound, the condensation rate of o-naphthoquinonediazide sulfonic acid with respect to the OH groups of phenols (reaction rate with respect to one OH group) is preferably 15% to 80%, more preferably 20%. ~
45%.

Further, as the o-quinonediazide compound used in the present invention, the following compounds described in JP-A-58-43451 can also be mentioned. That is, for example,
-Benzoquinonediazidesulfonic acid ester, 1,2-
Known 1,2- such as naphthoquinonediazidosulfonic acid ester, 1,2-benzoquinonediazidosulfonic acid amide, and 1,2-naphthoquinonediazidosulfonic acid amide
Quinonediazide compounds, more specifically, "Light-Sensitive Systems" by J. Kosar, 339-352 (1965)
Year), John Wille and Sands
y & Sons, Inc. (New York) and WSDe Forest, Photoresist, Vol. 50 (1975); McGraw Hill, New York 1,2-benzoquinonediazide-4-sulfonic acid phenyl ester, 1,2,1 ', 2'-di- (benzoquinonediazide-4-sulfonyl) -dihydroxybiphenyl, 1,2-benzoquinonediazide-4- (N- Ethyl-N-β-naphthyl) -sulfonamide, 1,2-naphthoquinonediazide-5-sulfonic acid cyclohexyl ester, 1- (1,2-naphthoquinonediazide-5-sulfonyl) -3,5-dimethylpyrazole, 2-Naphthoquinonediazide-5-sulfonic acid-4'-hydroxydiphenyl-4'-azo-β-naphthol Tel,
N, N-di- (1,2-naphthoquinonediazido-5-sulfonyl) -aniline, 2 '-(1,2-naphthoquinonediazide-5-sulfonyloxy) -1-hydroxy-
Anthraquinone, 1,2-naphthoquinonediazide-5
Sulfonic acid-2,4-dihydroxybenzophenone ester, 1,2-naphthoquinonediazide-5-sulfonic acid-2,3,4-trihydroxybenzophenone ester, 1,2-naphthoquinonediazide-5-sulfonic acid chloride 2 mol and 4 mol Condensate with 1 mol of 4,4'-diaminobenzophenone, 2 mol of 1,2-naphthoquinonediazide-5-sulfonic acid chloride and 4,4'-dihydroxy-
A condensate with 1 mol of 1,1'-diphenylsulfonic acid,
Condensate of 1 mol of 1,2-naphthoquinonediazide-5-sulfonic acid chloride with 1 mol of purprogalin, 1,2-
A 1,2-quinonediazide compound such as naphthoquinonediazide-5- (N-dihydroabietyl) -sulfonamide can be exemplified. In addition, Japanese Patent Publication No. 37-1953
Nos. 37-3627, 37-13109, 40-26126, 40-
No. 3801, No. 45-5604, No. 45-27345, No. 51-13013,
1,2-quinonediazide compounds described in JP-A-48-96575, JP-A-48-63802, and JP-A-48-63803 can also be mentioned.

Of the above o-quinonediazide compounds,
An o-quinonediazide ester compound obtained by reacting 1,2-benzoquinonediazidosulfonyl chloride or 1,2-naphthoquinonediazidosulfonylchloride with a pyrogallol-acetone condensed resin or 2,3,4-trihydroxybenzophenone is particularly preferred.

In the present invention, as the o-quinonediazide compound, the above compounds may be used alone or in combination of two or more kinds.

The proportion of the o-quinonediazide compound in the photosensitive composition is preferably 5 to 60% by weight, and particularly preferably 10 to 50% by weight.

It is preferable to further add an alkali-soluble resin to the photosensitive composition containing the o-quinonediazide compound.

In the present invention, the alkali-soluble resin which is preferably used in combination with the o-quinonediazide compound is, for example, a novolac resin, a vinyl polymer having a phenolic hydroxyl group, or the one described in JP-A-55-57841. Examples thereof include condensation resins of polyphenols with aldehydes or ketones.

Examples of the novolak resin include phenol / formaldehyde resin, cresol / formaldehyde resin, phenol / cresol / formaldehyde copolymer resin as described in JP-A-55-57841, and JP-A-55. Copolymer resins of p-substituted phenol and phenol or cresol and formaldehyde as described in JP-A-127553.

The molecular weight (standard for polystyrene) of the novolac resin is preferably 3.00 × 10 ^{2 to} 7.5 in terms of number average molecular weight Mn.
0 × 10 ³ , weight average molecular weight Mw is 1.00 × 10 ^{3 to} 3.00 × 10 ⁴ ,
More preferably, Mn is 5.00 × 10 ^{2 to} 4.00 × 10 ³ , and Mw is 3.
00 × 10 ^{3 to} 2.00 × 10 ⁴ .

The above novolak resins may be used alone or in combination of two or more kinds.

When a novolac resin is used in combination, it is preferable that the novolac resin is contained in the photosensitive composition in an amount of 5 to 95% by weight.

The vinyl polymer having a phenolic hydroxyl group is a polymer having a unit having the phenolic hydroxyl group in its molecular structure, and is represented by the following general formula [I] to
A polymer containing at least one structural unit represented by [V] is preferable.

[0086]

Embedded image

In the general formulas [I] to [V], R
₁ and R ₂ each represent a hydrogen atom, an alkyl group or a carboxyl group, preferably a hydrogen atom. R
₃ represents a hydrogen atom, a halogen atom or an alkyl group,
Preferred is a hydrogen atom or an alkyl group such as a methyl group or an ethyl group. R ₄ and R ₅ represent a hydrogen atom, an alkyl group, an aryl group or an aralkyl group, and are preferably a hydrogen atom. A represents an optionally substituted alkylene group connecting a nitrogen atom or an oxygen atom to an aromatic carbon atom, m represents an integer of 0 to 10, and B represents a substituent. Represents a phenylene group which may be substituted or a naphthylene group which may have a substituent.

The vinyl polymer having a phenolic hydroxyl group used in the present invention preferably has a copolymer type structure having the structural units represented by the general formulas [I] to [V]. Examples of the monomer to be copolymerized include ethylenically unsaturated olefins such as ethylene, propylene, isobutylene, butadiene, and isoprene, for example, styrene, α-methylstyrene, p
Styrenes such as -methylstyrene and p-chlorostyrene; for example, acrylic acids such as acrylic acid and methacrylic acid; for example, unsaturated aliphatic dicarboxylic acids such as itaconic acid, maleic acid, and maleic anhydride; for example, methyl acrylate , Ethyl acrylate, n-butyl acrylate,
Esters of α-methylene aliphatic monocarboxylic acids such as isobutyl acrylate, dodecyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, α-methyl methyl acrylate, methyl methacrylate, ethyl methacrylate and ethyl ethacrylate For example, nitriles such as acrylonitrile and methacrylonitrile, for example, amides such as acrylamide, for example, anilides such as acrylanilide, p-chloroacrylanilide, m-nitroacrylanilide, and m-methoxyacrylanilide, for example, acetic acid Vinyl esters such as vinyl, vinyl propionate, vinyl benzoate, and vinyl acetate, for example, vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, isobutyl vinyl ether, and β-chloroethyl vinyl ether , Vinyl chloride, vinylidene chloride, vinylidene cyanide, for example, 1-methyl-1-methoxyethylene, 1,1-dimethoxyethylene, 1,2-dimethoxyethylene, 1,1-dimethoxycarbonylethylene, 1-methyl-1- Ethylene derivatives such as nitroethylene, for example, N-vinylpyrrole,
N-vinyl carbazole, N-vinyl indole, N-
There are N-vinyl monomers such as vinylpyrrolidene and N-vinylpyrrolidone. These monomers are present in the polymer compound in a structure in which the unsaturated double bond is cleaved.

Of the above monomers, aliphatic monocarboxylic acid esters and nitriles are preferable because they exhibit excellent performance for the purpose of the present invention.

These monomers may be bonded to the polymer used in the present invention in either a block or random state.

When a vinyl polymer having a phenolic hydroxyl group is used in combination, the vinyl polymer having a phenolic hydroxyl group is preferably contained in the photosensitive composition in an amount of 0.5 to 70% by weight.

As the vinyl polymer having a phenolic hydroxyl group, the above polymers may be used alone or in combination of two or more kinds. It can also be used in combination with other polymer compounds.

When an alkali-soluble resin is used in combination, o-
The proportion of the quinonediazide compound in the photosensitive composition is preferably 5 to 60% by weight, particularly preferably 10 to 60% by weight.
50% by weight.

Further, an inclusion compound can be added to the photosensitive composition of the present invention.

The clathrate compound that can be used in the present invention is, so to speak, a host compound capable of incorporating (inclusion) a chemical species such as sodium ion or potassium ion into the clathrate compound as a guest molecule. There is no particular limitation so long as it is an organic compound soluble in the solvent used for preparing the photosensitive composition. Examples of such organic compounds include, for example, books such as "Host Guest Chemistry" (Michio Hiraoka, Kodansha, 1984, Tokyo) and "Tetrahedron Report" (No.226 (1987) P5).
725A. Collet et al., “Chemical Industry April Issue” ((1991) P278
Shinkai et al.), “Chemical Industry April Issue” ((1991) P288 Hiraoka et al.)
And the like are listed.

Inclusion compounds that can be preferably used in the present invention include, for example, cyclic D-glucans, cyclophanes, neutral polyligands, cyclic polyanions, cyclic polycations, cyclic peptides, SPHERANDS, Included are CAVITANDS and their acyclic analogs. Among these, cyclic D-glucans and acyclic analogs thereof, cyclophanes, and neutral polyligands are more preferable.

Examples of the cyclic D-glucans and acyclic analogs thereof include compounds in which α-D-glucopyranose is linked by a glycolide bond.

Examples of the compound include starch, amylose, amylopectin, and other sugars composed of D-glucopyranose groups, α-cyclodextrin, β-cyclodextrin, γ-cyclodextrin, and D-glucopyranose polymerization. Cyclodextrins such as cyclodextrin having a degree of 9 or more, and SO ₃ C ₆ H ₄ CH ₂ C ₆ H ₄
SO ₃ group, NHCH ₂ CH ₂ NH group, NHCH ₂ CH ₂ NH
CH ₂ CH ₂ NH group, SC ₆ H ₅ group, N ₃ group, NH ₂ group, NE
t ₂ group, SC (NH ⁺ ₂ ) NH ₂ group, SH group, SCH ₂ CH
_{2 The following} formula introducing a substituent such as NH ₂ group, imidazole group, ethylenediamine group, etc.

[0099]

Embedded image And modified D-glucans. Moreover, the cyclodextrin derivative represented by the following general formula [IX] and general formula [X], a branched cyclodextrin, a cyclodextrin polymer, etc. are also mentioned.

[0100]

Embedded image In the general formula [IX], R _{1 to} R ₃ may be the same or different and each represents a hydrogen atom, an alkyl group or a substituted alkyl group. In particular, those in which R _{1 to} R ₃ are hydrogen atoms, hydroxyethyl groups or hydroxypropyl groups are preferred, and the content of substituted alkyl groups in one molecule is 15%.
It is more preferably about 50%. n ₂ represents a positive integer of 4 to 10.

[0101]

Embedded image In the general formula [X], R is a hydrogen atom, —R ² —CO _{2
^{H, -R 2 -SO 3 H,}} -R 2 -NH 2 or -N-
(R ³ ) ₂ (R ² represents a linear or branched alkylene group having 1 to 5 carbon atoms, and R ³ represents a linear or branched alkyl group having 1 to 5 carbon atoms.

The production example of cyclodextrin is "Jo
unal of the American Chemical Society, Vol. 71, No. 3
P. 54, 1949, "Cheimish Berichte", vol. 90, p. 2561
1957, Vol. 90, page 2572, 1957, but is not of course limited to these.

The branched cyclodextrin used in the present invention is a known cyclodextrin in which a water-soluble substance such as glucose, maltose, cellobiose, lactose, sucrose, galactose or glucosamine, or a water-soluble substance such as disaccharide is branched or added. And preferably,
Maltosylcyclodextrin in which maltose is bound to cyclodextrin (the number of molecules bound to maltose may be one, two or three) or glucosylcyclodextrin in which glucose is bound to cyclodextrin (the number of molecules bound to glucose) Is one molecule, two molecules,
Or any of three molecules).

Specific methods for synthesizing these branched cyclodextrins are described in, for example, Starch Kagaku, Vol. 33, No. 2, 119.
-126 (1986), 127-132 (1986), starch chemistry,
Vol. 30, No. 2, pp. 231-239 (1983), etc., and can be synthesized with reference to these known methods. For example, maltosyl cyclodextrin can be prepared by using cyclodextrin and maltose as raw materials. And maltose by cyclodextrin using an enzyme such as isoamylase or pullulanase. Glucosylcyclodextrin can be produced in a similar manner.

Examples of the branched cyclodextrin preferably used in the present invention include the following specific exemplified compounds.

[Exemplary Compounds] D-1 α-Cyclodextrin with one molecule of maltose bound D-2 β-Cyclodextrin with one molecule of maltose D-3 γ-Cyclodextrin with one molecule of maltose D-4 malto Α-Cyclodextrin with two molecules of D-sulfate D-5 β-Cyclodextrin with two molecules of maltose D-6 γ-Cyclodextrin with two molecules of maltose D-7 α-Cyclodextrin with three molecules of maltose D-8 β-Cyclodextrin with 3 molecules of maltose D-9 γ-Cyclodextrin with 3 molecules of maltose D-10 α-Cyclodextrin with 1 molecule of glucose D-11 β-with 1 molecule of glucose bonded Cyclodextrin D-12 Glucose binds one molecule γ-Cyclodextrin D-13 Glucose-bonded 2 molecules α-Cyclodextrin D-14 Glucose-bonded 2 molecules β-Cyclodextrin D-15 Glucose-bonded 2 molecules γ-Cyclodextrin D-16 3 glucose molecules Bound α-cyclodextrin D-17 β-cyclodextrin bound to 3 molecules of glucose D-18 Gamma-cyclodextrin bound to 3 molecules of glucose

The structures of these branched cyclodextrins are analyzed by HPLC, NMR, TLC (thin layer chromatography), IN
EPT method (Insensitive nuclei enhanced by polarization
transfer) has been studied in various ways,
Even with the current science and technology, it has not yet been finalized and is in the stage of an estimated structure. However, each monosaccharide or 2
The fact that sugars and the like are bound to cyclodextrin is correct in the above measurement method. Therefore, in the present invention, when the monosaccharide or disaccharide polymolecule is bound to cyclodextrin, for example, when individually bound to each glucose of cyclodextrin as shown below, or It includes both those linearly linked to one glucose.

[0108]

[Chemical 6]

In these branched cyclodextrins,
Since the ring structure of the existing cyclodextrin is kept as it is, it shows the same inclusion function as the existing cyclodextrin, and the addition of highly water-soluble maltose or glucose dramatically increases the solubility in water. The feature is that it has improved.

The branched cyclodextrin used in the present invention can be obtained as a commercial product. For example, maltosyl cyclodextrin is commercially available as Isoeryte (registered trademark) manufactured by Shimizu Minato Sugar Co., Ltd.

Next, the cyclodextrin polymer used in the present invention will be described.

As the cyclodextrin polymer used in the present invention, those represented by the following general formula [XI] are preferable.

[0113]

[Chemical 7] [In formula, n < ₂ > is a polymerization degree and represents 3-4. ]

The cyclodextrin polymer used in the present invention can be produced by crosslinking cyclodextrin with, for example, epichlorohydrin to form a crosslinked polymer.

The cyclodextrin polymer preferably has a water solubility, that is, a solubility in water of 20 g or more per 100 ml of water at 25 ° C., for which purpose the degree of polymerization n ₂ in the above general formula [XI] is 3 to 3. The lower the value, the higher the water solubility of the cyclodextrin polymer itself and the solubilizing effect of the substance.

These cyclodextrin polymers are disclosed, for example, in JP-A-61-97025 and German Patent 3,544,842.
It can be synthesized by a general method described in the specification and the like.

The cyclodextrin polymer may also be used as an inclusion compound of the cyclodextrin polymer as described above.

Cyclophanes are cyclic compounds having a structure in which aromatic rings are linked by various bonds, and many compounds are known. Examples of cyclophanes include these known compounds. it can.

[0119] As the bond connecting an aromatic ring, for example, a single _{bond, - (CR 1 R 2)} m - _{bond, -O (CR 1 R 2)} m O- _{bond, -NH (CR 1 R 2)} m NH − Bond, − (CR ₁ R ₂ ) _p
NR ₃ (CR ₄ R ₅ ) _q -bond,-(CR ₁ R ₂ ) _p N ⁺ R ₃ R ₄
(CR ₅ R ₆ ) _q -bond,-(CR ₁ R ₂ ) _p S ⁺ R ₃ (CR ₄
R ₅ ) _q -bond, -CO ₂ -bond, -CONR-bond (where R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ may be the same or different and a hydrogen atom Or an alkyl group having 1 to 3 carbon atoms, and m, p and q may be the same or different, and represent an integer of 1 to 4).

Examples of the compound include compounds represented by the following formulas:

[0121]

Embedded image The following formula represented by paracyclophanes, tri-o-tymotide, and cycloriveratrilene represented by

[0122]

Embedded image The following formula represented by orthocyclophanes, metacyclophphane, calixarene, resorcinol-aldehyde cyclic oligomers represented by

[0123]

Embedded image Metacyclophanes represented by

[0124]

Embedded image Para-substituted phenolic acyclic oligomers represented by

Neutral polyligands include crown compounds, cryptands, cyclic polyamines and their acyclic analogs. The compound is known to effectively incorporate metal ions, but can also effectively incorporate cationic organic molecules.

Other inclusion compounds include urea, thiourea, deoxycholic acid, dinitrodiphenyl, hydroquinone, o-trithymotide, oxyflavan, dicyanoamminenickel, dioxytriphenylmethane, triphenylmethane, methylnaphthalene, spirochroman, Examples include perhydrotriphenylene, clay minerals, graphite, zeolites (faujasite, chabazite, mordenite, levinite, montmorillonite, halosite, etc.), cellulose, amylose, proteins and the like.

These clathrate compounds may be added as a simple substance, but they improve the solubility of the clathrate compound itself or the clathrate compound incorporating the molecule in a solvent and the compatibility with other additives. For this reason, a polymer in which a substituent having an inclusion ability is suspended as a pendant substituent may be added together with the polymer.

Examples of the polymer include those disclosed in JP-A-3-221501, JP-A-3-221502, JP-A-3-221503,
It can be easily obtained by using a method as disclosed in JP-A-3-221504 and JP-A-3-221505.

Of the above inclusion compounds, cyclic and acyclic D-glucans, cyclophanes, and acyclic cyclophane analogs are preferable. More specifically, cyclodextrin, calixarene, resorcinol-aldehyde cyclic oligomer, and para-substituted phenols acyclic oligomer are preferred.

Cyclodextrin and its derivatives are most preferred, and β-cyclodextrin and its derivatives are more preferred.

Further, a printout material capable of forming a visible image by exposure can be added to the photosensitive composition of the present invention. Printout materials consist of a compound that generates an acid or a free radical upon exposure to light and an organic dye that changes its color by interacting with the generated acid or a free radical. As the compound, for example, JP-A-50-36209
O-naphthoquinonediazide-4-sulfonic acid halogenide described in JP-A-53-36223, trihalomethyl-2-pyrone and trihalomethyl-triazine described in JP-A-53-36223,
An ester compound or amide compound of o-naphthoquinonediazide-4-sulfonic acid chloride described in JP-A-55-6244 and a phenol or aniline having an electron-withdrawing substituent, JP-A-55-77742, JP-A-57-1
Examples of the halomethyl vinyl oxadiazole compound and diazonium salt described in JP 48784 publication,
Examples of organic dyes include Victoria Pure Blue BOH (Hodogaya Chemical Co., Ltd.), Patent Pure Blue (Sumitomo Mikuni Chemical Co., Ltd.), and Oil Blue #.
603 (manufactured by Orient Chemical Industry Co., Ltd.), Sudan Blue I
I (manufactured by BASF), crystal violet, malachite green, fuchsin, methyl violet, ethyl violet, methyl orange, brilliant green,
Examples thereof include Congo Red, Eosin, Rhodamine 66 and the like.

In addition to the above-mentioned materials, the photosensitive composition of the present invention may optionally contain a plasticizer, a surfactant, an organic acid,
Acid anhydrides and the like can be added.

Further, in order to improve the oil sensitivity of the photosensitive composition, the photosensitive composition of the present invention contains, for example, p-
tert-butylphenol formaldehyde resin, pn
Octylphenol formaldehyde resins or resins in which these resins are partially esterified with an o-quinonediazide compound can also be added.

The layer of the photosensitive composition of the present invention can be formed by applying a coating solution prepared by dissolving or dispersing the photosensitive composition comprising each of these components in a solvent onto a support and drying it. it can.

Examples of the solvent which can be used for dissolving the photosensitive composition include methyl cellosolve, methyl cellosolve acetate, ethyl cellosolve, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl. Ether, diethylene glycol diethyl ether, diethylene glycol monoisopropyl ether, propylene glycol, propylene glycol monoethyl ether acetate, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol methyl ethyl ether, ethyl formate, propylic acid formate , Butyl formate, amyl formate, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl propionate, ethyl propionate, methyl butyrate,
Examples include ethyl butyrate, dimethylformamide, dimethyl sulfoxide, dioxane, acetone, methyl ethyl ketone, cyclohexanone, methylcyclohexanone, diacetone alcohol, acetylacetone, and γ-butyrolactone. These solvents can be used alone or in combination of two or more.

The coating method used when the photosensitive composition is coated on the support surface is a conventionally known method, for example, spin coating, wire bar coating, dip coating, air knife coating, spray coating, air spray coating, Methods such as electrostatic air spray coating, roll coating, blade coating and curtain coating are used. At this time, the coating amount varies depending on the application, but for example, a coating amount of 0.05 to 5.0 g / m ² as a solid content is preferable.

The photosensitive lithographic printing plate of the present invention can be made into a plate by exposing and developing it in a usual manner. For example, a transparent original image having a line image, a halftone image or the like is brought into close contact with a photosensitive surface and exposed, and then the photosensitive layer is removed using an appropriate developing solution to obtain a relief image.

As a light source suitable for exposure, a mercury lamp, a metal halide lamp, a xenon lamp, a chemical lamp,
And carbon arc lamps. Further, as the developer used for development, for example, sodium silicate, alkali metal silicate such as potassium silicate, sodium hydroxide,
An alkaline aqueous solution such as an aqueous solution of potassium hydroxide, tribasic sodium phosphate, dibasic sodium phosphate, sodium carbonate, potassium carbonate and the like can be used. The concentration of the aqueous alkali solution at this time varies depending on the type of the photosensitive composition and the alkali, but is generally in the range of 0.1 to 10% by weight. Further, an organic solvent such as a surfactant or alcohol can be added to the aqueous alkali solution as needed.

[0139]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to examples, but the present invention is not limited to these examples.

Example 1 [Preparation of support 1-1] An aluminum plate having a thickness of 0.3 mm (material JIS standard A1050, temper H16) was immersed in a 10 wt% sodium hydroxide aqueous solution kept at 85 ° C. Then, it was degreased for 1 minute and washed with water. The degreased aluminum plate was immersed in a 10 wt% sulfuric acid aqueous solution kept at 25 ° C. for 1 minute, desmutted, and washed with water.

Then, the average particle size was applied to the aluminum plate.
10 μm Al ₂ O ₃ particles were mixed in water at a volume ratio of 10 times, and the dispersion liquid was uniformly dispersed by a stirrer. The pressure was 6 kg / 60 kg from a 60 nozzle having a diameter of 2 mm. cm ²
Inject at 10 at an angle of 30 degrees to the aluminum plate surface
It was made to collide from a distance of 0 mm.

Then, it was dipped in a 10 wt% sodium hydroxide aqueous solution kept at 70 ° C. for 10 seconds, then dipped in a 10 wt% sulfuric acid aqueous solution kept at 25 ° C. for 10 seconds, desmutted, and washed with water. did.

Next, using 1.5% by weight nitric acid aqueous solution as an electrolytic solution, the aluminum plate was subjected to an alternating current,
Temperature 40 ° C., for 1 second electrolytic graining treatment at a current density of 200A / dm ^2, further, the current density 100A / dm ^2, the amount of electricity 40
The electrolytic surface roughening treatment was performed under the condition of 0 C / dm ² . Then 70
It was immersed in a 10 wt% sodium hydroxide aqueous solution kept at 0 ° C for 10 seconds, then immersed in a 10 wt% sulfuric acid aqueous solution kept at 25 ° C for 10 seconds, desmutted, and washed with water.

Then, in a 20% by weight aqueous solution of sulfuric acid, a temperature of 35
The amount of oxide film is 2.0 to 3.0 under the conditions of ℃ and current density 3A / dm ^2.
Anodizing treatment was performed so as to obtain g / dm ² . Then 8
In a 0.1% by weight aqueous ammonium acetate solution kept at 0 ° C
The substrate was immersed for 30 seconds for sealing, and dried at 80 ° C. for 5 minutes to obtain a support 1-1.

When the pit order of the roughened support thus obtained was examined, it was found to have a secondary pit structure. For the largest pit (secondary pit on this rough surface), a high-resolution scanning electron microscope observation was performed at a randomly selected location with a magnification of 1000 and a measurement area of 60000 μm ² , and the ratio of the pit opening area to the measurement area ( The upper projected area ratio) was examined and found to be 0.83.

[Preparation of Support 1-2] In preparation of Support 1-1, electrolytic surface roughening treatment was carried out by using 1.5% by weight of hydrochloric acid as an electrolytic solution and by applying an alternating current at a temperature of 40 ° C. and a current density.
Support similar to Support 1-1 except that electrolytic surface roughening treatment was performed for 1 ^{second under} the condition of 200 A / dm ^{2 and further under} the conditions of current density 80 A / dm ² and electricity amount 800 C / dm ^2. 1-2 was obtained.

When the pit order of the roughened support thus obtained was examined, it was found to have a tertiary pit structure. Moreover, when the ratio of the pit opening area to the apparent area (upper projected area ratio) was examined for the largest pit (the tertiary pit on this rough surface), it was found to be 0.
It was 76.

[Preparation of support 1-3] In preparation of the support 1-1, electrolytic surface roughening treatment is performed in electrolytic surface roughening.
Using 1.5 wt% hydrochloric acid as an electrolytic solution, electrolytic surface roughening treatment was performed for 1 second at a temperature of 40 ° C. and a current density of 200 A / dm ² with an alternating current, and further, a current density of 80 A / dm ² and an electric quantity of 400 C A support 1-3 was obtained in the same manner as the support 1-1 except that the conditions were / dm ² .

The pit order of the roughened support thus obtained was examined and found to have a secondary pit structure. The maximum pit (secondary pit on this rough surface) was examined for the ratio of the pit opening area to the apparent area (upper projected area ratio).
It was 52.

[Preparation of support 1-4] In preparation of the support 1-1, electrolytic surface roughening treatment is performed in electrolytic surface roughening.
A 1.5% by weight nitric acid aqueous solution was used as the electrolyte, and the temperature was 40 ° C, the current density was 40 A / dm ² , and the electricity was 400 C /
A support 1-4 was obtained in the same manner as the support 1-1 except that the conditions were dm ² .

The pit order of the roughened support thus obtained was examined and found to have a primary pit structure. Moreover, when the ratio of the pit opening area to the apparent area (upper projected area ratio) was examined for the largest pit (the primary pit on this rough surface), it was found to be 0.
It was 78.

[Preparation of Support 1-5] In preparation of the support 1-1, electrolytic roughening treatment is performed in electrolytic roughening.
1.5% by weight nitric acid was used as an electrolytic solution, and the temperature was 40 ° C, the current density was 20 A / dm ² , and the electricity was 200 C / dm ² by alternating current
A support 1-5 was obtained in the same manner as the support 1-1 except that the above conditions were used.

The pit order of the roughened support thus obtained was examined and found to have a primary pit structure. Moreover, when the ratio of the pit opening area to the apparent area (upper projected area ratio) was examined for the largest pit (the primary pit on this rough surface), it was found to be 0.
It was 66.

Table 1 shows a list of the pit order and the maximum projected area ratio of the maximum pits of the obtained supports 1-1 to 1-5.

[0155]

[Table 1]

[Preparation of Photosensitive Lithographic Printing Plate Samples 1-1 to 1-5] A positive photosensitive composition coating solution having the following composition was applied onto a support 1-1 to 1-5 using a wire bar. And 80 ℃
After drying for 2 minutes, the photosensitive lithographic printing plate samples 1-1 to 1-5
It was created. The coating amount of the positive photosensitive composition coating liquid was set to 2.0 g / m ² as a dry weight.

<Positive Photosensitive Composition Coating Liquid> Novolac resin (phenol / m-cresol / p-cresol molar ratio 10/54/36, weight average molecular weight 4000) 6.70 g Pyrogallol acetone resin (weight average molecular weight 3000 ) And o-naphthoquinonediazide-5-sulfonyl chloride condensate (esterification rate 30%) 1.50 g polyethylene glycol # 2000 0.20 g Victoria Pure Blue BOH (Hodogaya Chemical Co., Ltd.) 0.080 g 2,4-bis (trichloro) Methyl) -6- (p-methoxystyryl) -s-triazine 0.15 g FC-430 (Sumitomo 3M Ltd.) 0.03 g cis-1,2-cyclohexanedicarboxylic acid 0.20 g methyl cellosolve 100 ml

[Preparation of photosensitive lithographic printing plate sample 1-6] A negative photosensitive composition coating solution having the following composition was coated on a support 1-1 using a wire bar and dried at 80 ° C for 2 minutes. Then
Photosensitive lithographic printing plate samples 1-6 were prepared. The coating amount of the negative photosensitive composition coating liquid was set to 2.0 g / m ² as a dry weight.

<Negative-type photosensitive composition coating liquid> Copolymer (p-hydroxyphenylmethacrylamide / acrylonitrile / ethyl acrylate / methacrylic acid = 10/25/57/8 weight average molecular weight 60000) 5.0 g diazo resin 0.5 g Julimer AC-10L (manufactured by Nippon Pure Chemical Co., Ltd.) 0.05 g Victoria Pure Blue BOH (manufactured by Hodogaya Chemical Co., Ltd.) 0.1 g Methyl Cellosolve 100 ml

The obtained photosensitive lithographic printing plate samples 1-1 to 1
No. 6 was exposed to light at 8 mW / cm ² for 60 seconds using a 4 kW metal halide lamp as a light source for image exposure. The exposed photosensitive lithographic printing plate samples 1-1 to 1-
6 was developed using a commercially available developer [SDR-1 (manufactured by Konica Corporation) diluted 6 times] at a developing time of 20 seconds and a developing temperature of 27 ° C.

The lithographic printing plate thus obtained was evaluated for stain resistance and printing durability by the following evaluation methods.

[Evaluation method] <Evaluation of stain resistance> The obtained lithographic printing plate was heated at 250 ° C. for 60 seconds using a burning device. After cooling to room temperature, it was thoroughly washed with water and gummed. Printing was performed under the same conditions using the obtained gum-coated planographic printing plate, the degree of stain resistance was visually observed, and the stain resistance was evaluated according to the following evaluation criteria. (Evaluation Criteria) ⊚: No stain was generated ∘: Slightly stain Δ: Partially stain ×: Whole was severely stain

<Evaluation of Printing Durability> Using the gummed planographic printing plate used for the evaluation of stain resistance, printing was performed under the same conditions,
Printing was performed until defective ink replenishment appeared in the image area of the printed matter or ink inked in the non-image area, and the printing durability was evaluated by the number of prints at that time.

Table 2 shows the evaluation results obtained.

[0165]

[Table 2]

Example 2 [Preparation of support 2-1] An aluminum plate having a thickness of 0.3 mm (material JIS standard A1050, temper H16) was immersed in a 10 wt% sodium hydroxide aqueous solution kept at 85 ° C. Then, it was degreased for 1 minute and washed with water. The degreased aluminum plate was immersed in a 10 wt% sulfuric acid aqueous solution kept at 25 ° C. for 1 minute, desmutted, and washed with water.

Then, the average particle size was applied to the aluminum plate.
10 μm Al ₂ O ₃ particles were mixed in water at a volume ratio of 10 times, and the dispersion liquid was uniformly dispersed by a stirrer. The pressure was 6 kg / 60 kg from a 60 nozzle having a diameter of 2 mm. cm ²
, And collided with the surface of the aluminum plate from a distance of 100 mm at an angle of 30 degrees.

Then, it was immersed in a 10% by weight sodium hydroxide aqueous solution kept at 70 ° C. for 10 seconds, then in a 10% by weight sulfuric acid aqueous solution kept at 25 ° C. for 10 seconds, desmutted, and washed with water. did.

Then, using 2.0% by weight hydrochloric acid aqueous solution as an electrolytic solution, the aluminum plate was subjected to an alternating current,
Electrolytic surface roughening treatment is performed for 1 second at a temperature of 30 ° C and a current density of 200 A / dm ² , and further, a current density of 25 A / dm ² and an electric quantity of 300
The electrolytic surface roughening treatment was performed under the condition of C / dm ² . Then 70
It was immersed in a 10 wt% sodium hydroxide aqueous solution kept at 0 ° C for 10 seconds, then immersed in a 10 wt% sulfuric acid aqueous solution kept at 25 ° C for 10 seconds, desmutted, and washed with water.

Then, in a 20% by weight aqueous solution of sulfuric acid, a temperature of 35
The amount of oxide film is 2.0 to 3.0 under the conditions of ℃ and current density 3A / dm ^2.
Anodizing treatment was performed so as to obtain g / dm ² . Then 8
In a 0.1% by weight aqueous ammonium acetate solution kept at 0 ° C
The substrate was immersed for 30 seconds for sealing, and dried at 80 ° C. for 5 minutes to obtain a support 2-1.

With respect to the roughened support thus obtained, a pit structure was observed at a randomly selected place using a high resolution scanning electron microscope capable of obtaining a magnification of 1,000 to 50,000 times. . The average diameter-converted diameter of 100 pits (pit average diameter) was 0.84 μm.

Further, the minimum unit pit (primary pit) is confirmed from the observed image of 10,000 to 50,000 times, and then the secondary pit having the minimum unit pit on its wall surface is confirmed. When it is not possible to check at 10,000 to 50,000 times, lower the observation magnification and check the secondary pit. Magnification of the primary pit is 1000
After observing at 200 points or more at 0 times, the ratio of the primary pits, which are not included in the wall surface of the secondary pits and exist independently, to the total number of primary pits (single ratio of primary pits) was determined. The number of primary pits which were not included in the wall surface of the secondary pits and existed independently of the total number of primary pits was 88%.

Further, regarding the primary pit, the ratio of the opening area of the primary pit to the apparent area (upper projected area ratio)
Was 0.78.

Next, the roughened support was cut, and the cut surface was observed at a magnification of 15,000 to obtain a cross-sectional photograph of 50 primary pits. For these pits, "pit diameter" and "maximum depth in the direction perpendicular to the diameter" are measured, and "pit diameter" is shown in the X-axis data and "maximum depth in the direction perpendicular to the diameter" for Y-axis data. Then, the linear regression analysis was conducted, and the linear gradient (pit diameter and pit depth inclination) obtained by the linear regression analysis was 0.52.

[Preparation of support 2-2] In preparation of support 2-1, electrolytic surface roughening treatment was carried out by using a 2.0 wt% hydrochloric acid aqueous solution as an electrolytic solution and by applying an alternating current at a temperature of 30 ° C and a current density. Support similar to Support 2-1 except that electrolytic surface roughening treatment was performed for 1 ^{second under} the condition of 200 A / dm ^{2 and further} under conditions of current density 10 A / dm ² and electricity quantity 300 C / dm ^2. Two
-2 was obtained.

For the roughened support thus obtained, the average pit diameter, the primary pit single ratio, the upper projected area ratio, the pit diameter and the pit depth inclination were determined in the same manner as above. As a result, the average pit diameter was 0.88 μm, the primary pit single ratio was 83%, the upper projected area ratio was 0.73, and the pit diameter-pit depth inclination was 0.28.

[Preparation of support 2-3] In preparation of the support 2-1, electrolytic surface roughening treatment was carried out by using a 2.0% by weight hydrochloric acid aqueous solution as an electrolytic solution and by applying an alternating current at a temperature of 30 ° C and a current density. Support similar to Support 2-1 except that electrolytic surface roughening treatment was performed for 1 ^{second under} the condition of 200 A / dm ^{2 and further under} the conditions of current density 3 A / dm ² and quantity of electricity 200 C / dm ^2. Two
-3 was obtained.

For the roughened support thus obtained, the average pit diameter, primary pit single ratio, upper projected area ratio, pit diameter and pit depth inclination were determined in the same manner as above. As a result, the average pit diameter was 0.63 μm, the primary pit single ratio was 91%, the upper projected area ratio was 0.48, and the pit diameter-pit depth inclination was 0.17.

[Preparation of Support 2-4] In preparation of the support 2-1, electrolytic surface roughening treatment was carried out by using 2.0 wt% nitric acid aqueous solution as an electrolytic solution and by applying an alternating current at a temperature of 30 ° C. and a current density. A support 2-4 was obtained in the same manner as the support 2-1, except that the conditions were 20 A / dm ² and an electric quantity of 500 C / dm ² .

For the roughened support thus obtained, the average pit diameter, primary pit single ratio, upper projected area ratio, pit diameter and pit depth inclination were determined in the same manner as above. As a result, the average pit diameter was 1.30 μm, the primary pit single ratio was 96%, the upper projected area ratio was 0.64, and the pit diameter-pit depth inclination was 0.24.

[Preparation of Support 2-5] In preparation of Support 2-1, electrolytic surface roughening treatment was carried out by using a 2.0 wt% nitric acid aqueous solution as an electrolytic solution and by applying an alternating current at a temperature of 30 ° C. and a current density. A support 2-5 was obtained in the same manner as the support 2-1, except that the conditions were 50 A / dm ² and an electric quantity of 400 C / dm ² .

For the roughened support thus obtained, the average pit diameter, the primary pit single ratio, the upper projected area ratio, the pit diameter and the pit depth inclination were determined in the same manner as above. As a result, the average pit diameter was 1.70 μm, the primary pit single ratio was 85%, the upper projected area ratio was 0.67, and the pit diameter-pit depth inclination was 0.35.

[Preparation of Support 2-6] In preparation of the support 2-1, electrolytic surface roughening treatment was carried out by using an aqueous 2.0 wt% nitric acid solution as an electrolytic solution and applying an alternating current at a temperature of 30 ° C. and a current density. A support 2-6 was obtained in the same manner as the support 2-1, except that the conditions were 50 A / dm ² and an electric quantity of 300 C / dm ² .

For the roughened support thus obtained, the average pit diameter, the primary pit single ratio, the upper projected area ratio, the pit diameter and the pit depth inclination were determined in the same manner as above. As a result, the pit average diameter was 1.60 μm, the primary pit single ratio was 72%, the upper projected area ratio was 0.42, and the pit diameter-pit depth inclination was 0.31.

[Preparation of Support 2-7] In preparation of Support 1, electrolytic roughening treatment was carried out by using 2.0 wt% nitric acid aqueous solution as an electrolytic solution and by applying an alternating current, a temperature of 30 ° C. and a current density of 100 A / A support 2-7 was obtained in the same manner as the support 2-1, except that the conditions were dm ² and an electric quantity of 400 C / dm ² .

For the roughened support thus obtained, the average pit diameter, the primary pit single ratio, the upper projected area ratio, the pit diameter and the pit depth inclination were determined in the same manner as above. As a result, the pit average diameter was 2.30 μm, the primary pit single ratio was 48%, the upper projected area ratio was 0.37, and the pit diameter-pit depth inclination was 0.11.

Table 3 shows a list of the average pit diameters of the obtained supports 2-1 to 2-7, the primary pit single ratio, the upper projected area ratio, and the inclinations of the pit diameter and the pit depth.

[0188]

[Table 3]

[Preparation of Photosensitive Lithographic Printing Plate Samples 2-1 to 2-7] A positive photosensitive composition coating solution having the following composition was coated on a support 2-1 to 2-7 using a wire bar. And 80 ℃
After drying for 2 minutes, the photosensitive lithographic printing plate samples 2-1 to 2-7
It was created. The coating amount of the positive photosensitive composition coating liquid was set to 2.0 g / m ² as a dry weight.

<Positive Photosensitive Composition Coating Liquid> Novolac resin (phenol / m-cresol / p-cresol molar ratio 10/54/36, weight average molecular weight 4000) 6.70 g Pyrogallol acetone resin (weight average molecular weight 3000 ) And o-naphthoquinonediazide-5-sulfonyl chloride condensate (esterification rate 30%) 1.50 g polyethylene glycol # 2000 0.20 g Victoria Pure Blue BOH (Hodogaya Chemical Co., Ltd.) 0.080 g 2,4-bis (trichloro) Methyl) -6- (p-methoxystyryl) -s-triazine 0.15 g FC-430 (Sumitomo 3M Ltd.) 0.03 g cis-1,2-cyclohexanedicarboxylic acid 0.20 g methyl cellosolve 100 ml

[Preparation of photosensitive lithographic printing plate sample 2-8] A negative photosensitive composition coating solution having the following composition was coated on a support 2-1 using a wire bar and dried at 80 ° C for 2 minutes. Then
A photosensitive lithographic printing plate sample 2-8 was prepared. The coating amount of the negative photosensitive composition coating liquid was set to 2.0 g / m ² as a dry weight.

<Negative-type photosensitive composition coating liquid> Copolymer (p-hydroxyphenylmethacrylamide / acrylonitrile / ethyl acrylate / methacrylic acid = 10/25/57/8 weight average molecular weight 60000 5.0 g diazo resin 0.5 g Julimer AC-10L (manufactured by Nippon Pure Chemical Industries, Ltd.) 0.05 g Victoria Pure Blue BOH (manufactured by Hodogaya Chemical Co., Ltd.) 0.1 g Methyl Cellosolve 100 ml

The obtained photosensitive lithographic printing plates 2-1 to 2-8
For, the stain resistance was evaluated in the same manner as in Example 1, and the dot reproducibility and the K value were evaluated by the following evaluation methods. <Evaluation of small dot reproducibility> Exposure and development are performed under the following conditions,
The reproducibility (A) of the FOGRA fine line on the plate was determined, and the reproducibility of the dot area ratio (B) using a 50% halftone original was measured with a Macbeth reflection densitometer RD-918.

Exposure amount: Kodak step tablet, equivalent to 4 steps of clear Exposure device: 4 kw metal halide lamp, distance 60 cm Development: Automatic developing machine PSU-820 manufactured by Konica, Developer SD-32 manufactured by Konica

<Evaluation of K Value> The lithographic printing plate obtained by exposing and developing under the above conditions was placed on a printing machine (DAIYA1F-1 manufactured by Mitsubishi Heavy Industries, Ltd.), coated paper, dampening water (Tokyo Ink). Etch solution SG-51 concentration 1.5
%), Ink (Toyo Ink Mfg. Co., Ltd. High Plus M)
(Red) was used and printing was performed so that the density of the image area was 1.6. Screen line number 150 lin on the obtained printed matter
Measure the density of 80% halftone dot of e / inch, and use the following formula to calculate K
Values were calculated. The concentration was measured with a Macbeth densitometer.

K value = (image portion density-80% halftone dot density) / image portion density The larger the K value, the better the reproducibility of the high density halftone dot portion.

Table 4 shows the obtained evaluation results.

[0198]

[Table 4]

Example 3 [Preparation of support 3-1] An aluminum plate having a thickness of 0.3 mm (material JIS standard A1050, temper H16) was immersed in a 6 wt% sodium hydroxide aqueous solution kept at 85 ° C. Then, it was degreased for 12 seconds and washed with water. The degreased aluminum plate was immersed in a 10 wt% sulfuric acid aqueous solution kept at 25 ° C. for 5 seconds, desmutted, and washed with water.

Then, this aluminum plate was used as an electrolytic solution in a 2 wt% nitric acid aqueous solution and subjected to a sinusoidal alternating current of 60 Hz at a temperature of 25 ° C., a current density of 30 A / dm ² , and an electric power of 800 C.
After electrolytic surface-roughening treatment under the condition of / dm ² , it is immersed in a 30 wt% sulfuric acid aqueous solution kept at 60 ° C for 30 seconds, and mainly contains aluminum hydroxide produced by electrolytic surface-roughening treatment. The smut component was removed.

The roughened aluminum plate thus obtained was cut, and 20 randomly selected cut surfaces were photographed.
As a result of randomly selecting and observing 0 pits, the average diameter of the pit openings was 1.7 μm, and the average depth in the direction perpendicular to the pit diameter was 0.95 μm. In addition, sharp parts (pit edges) formed between pits of 0.5 μm or more were also observed.

This aluminum plate was kept at 40 ° C. 6
Alkaline etching was performed for 10 seconds in a weight% sodium hydroxide aqueous solution. Then, anodization treatment was performed for 1 minute in a 20 wt% sulfuric acid aqueous solution at a temperature of 35 ° C. and a current density of 3 A / dm ² . After that, it was immersed in a 0.1% by weight ammonium acetate aqueous solution kept at 80 ° C for 30 seconds for sealing treatment,
The support 3-1 was obtained after drying at 80 ° C. for 5 minutes.

The roughened support thus obtained was cut, and 40 randomly selected cut surfaces were photographed.
0.5μm by 10,000 times high resolution scanning electron micrograph
As a result of randomly selecting 50 places sandwiched between the above pits and observing them, 85% of the pits are the average of the pit openings of the concave pits of the roughened aluminum plate according to the following formula 1. 1.7 μm diameter and average depth in the direction perpendicular to the pit diameter
Range of radius of curvature calculated by substituting 0.95 μm (0.012 ~
0.173 μm).

[0204]

(Equation 8) The surface roughness of the support is such that Ra is 0.71 μm and Rz is 4.0.
A 2 [mu] m, the area A was 104.1μm ^2.

The surface roughness Ra and Rz of the rough surface of the support.
Is obtained according to JIS B0601.

[Preparation of Support 3-2] An aluminum plate having a thickness of 0.3 mm (material JIS standard A1050, temper H16) is
It was immersed in a 6 wt% sodium hydroxide aqueous solution kept at 0 ° C, degreased for 12 seconds, and then washed with water. The degreased aluminum plate was immersed in a 10 wt% sulfuric acid aqueous solution kept at 25 ° C. for 5 seconds, desmutted, and washed with water.

Then, this aluminum plate was used as an electrolytic solution in a 1% by weight hydrochloric acid aqueous solution and subjected to a sinusoidal alternating current of 60 Hz at a temperature of 25 ° C., a current density of 50 A / dm ² , and an electric power of 800 C.
After electrolytic surface-roughening treatment under the condition of / dm ² , it is immersed in a 30 wt% sulfuric acid aqueous solution kept at 60 ° C for 30 seconds, and mainly contains aluminum hydroxide produced by electrolytic surface-roughening treatment. The smut component was removed.

With respect to the roughened aluminum plate thus obtained, the average diameter of the pit openings and the direction perpendicular to the pit diameter are described in the same manner as described in [Preparation of support 3-1]. When the average depth was determined, the average diameter of the pit openings was 6.4 μm, and the average depth in the direction perpendicular to the pit diameter was 1.60 μm. In addition, sharp parts (pit edges) formed between pits of 0.5 μm or more were also observed.

This aluminum plate was kept at 40 ° C. 6
Alkaline etching was performed for 7 seconds in a weight% sodium hydroxide aqueous solution. Then, anodization treatment was performed for 1 minute in a 20 wt% sulfuric acid aqueous solution at a temperature of 35 ° C. and a current density of 3 A / dm ² . After that, it was immersed in a 0.1% by weight ammonium acetate aqueous solution kept at 80 ° C for 30 seconds for sealing treatment,
The support 3-2 was obtained by drying at 80 ° C. for 5 minutes.

Regarding the roughened support thus obtained, in the same manner as described in [Preparation of support 3-1], a part sandwiched by pits of 0.5 μm or more was randomly selected. As a result of selecting and observing 50 places in the above, 95% of the parts were found to be the average diameter of 6.4 μm of the pit opening of the concave pits of the roughened aluminum plate and the average in the direction perpendicular to the pit diameter in the above-mentioned Formula 1. The radius of curvature was within the range of the radius of curvature (0.001-0.253 μm) calculated by substituting the depth of 1.60 μm.

The surface roughness Ra of the support is 0.81 μm.
m and Rz were 4.79 μm, and the area A was 145.3 μm ² .

[Preparation of Support 3-3] An aluminum plate having a thickness of 0.3 mm (material JIS standard A1050, temper H16)
It was immersed in a 6 wt% sodium hydroxide aqueous solution kept at 0 ° C, degreased for 12 seconds, and then washed with water. The degreased aluminum plate was immersed in a 10 wt% sulfuric acid aqueous solution kept at 25 ° C. for 5 seconds, desmutted, and washed with water.

Next, while supplying a dispersion liquid in which an abrasive (alumina # 800) was dispersed in water at a concentration of 20% by weight to this aluminum plate at a supply rate of 20 liters / min,
Brush polishing was carried out at a brush rotation speed of 240 rpm and a conveying speed of 2.0 m / min for mechanical roughening.

Then, it was immersed in a 10% by weight sodium hydroxide aqueous solution kept at 70 ° C. for 10 seconds, then in a 10% by weight sulfuric acid aqueous solution kept at 25 ° C. for 10 seconds, desmutted, and washed with water. did.

Next, this aluminum plate was used as an electrolytic solution in a 2% by weight aqueous nitric acid solution and subjected to a sinusoidal alternating current of 60 Hz at a temperature of 25 ° C., a current density of 30 A / dm ² , and an electric power of 200 C.
After electrolytic surface-roughening treatment under the condition of / dm ² , it is immersed in a 30 wt% sulfuric acid aqueous solution kept at 60 ° C for 30 seconds, and mainly contains aluminum hydroxide produced by electrolytic surface-roughening treatment. The smut component was removed.

With respect to the roughened aluminum plate thus obtained, the average diameter of the pit openings and the direction perpendicular to the pit diameter were described in the same manner as described in [Preparation of support 3-1]. When the average depth was determined, the average diameter of the pit openings was 1.2 μm, and the average depth in the direction perpendicular to the pit diameter was 0.57 μm. In addition, sharp parts (pit edges) formed between pits of 0.5 μm or more were also observed.

This aluminum plate was kept at 40 ° C. 6
Alkaline etching was performed for 7 seconds in a weight% sodium hydroxide aqueous solution. Then, anodization treatment was performed for 1 minute in a 20 wt% sulfuric acid aqueous solution at a temperature of 35 ° C. and a current density of 3 A / dm ² . After that, it was immersed in a 0.1% by weight ammonium acetate aqueous solution kept at 80 ° C for 30 seconds for sealing treatment,
The support 3-3 was obtained after drying at 80 ° C. for 5 minutes.

With respect to the roughened support thus obtained, a portion sandwiched by pits of 0.5 μm or more was randomly selected in the same manner as described in [Preparation of support 3-1]. As a result of selecting and observing 50 spots in the above, 76% of the parts were found to be in the above formula 1 and the average diameter of the pit openings of the concave pits of the roughened aluminum plate was 1.2 μm and the average in the direction perpendicular to the pit diameter. The radius of curvature was within the range of radius of curvature (0.010 to 0.074 μm) calculated by substituting the depth of 0.57 μm.

The surface roughness Ra of the support is 0.66 μm.
m and Rz were 3.91 μm, and the area A was 114.2 μm ² .

[Preparation of support 3-4] An aluminum plate having a thickness of 0.3 mm (material JIS standard A1050, temper H16)
It was immersed in a 6 wt% sodium hydroxide aqueous solution kept at 0 ° C, degreased for 12 seconds, and then washed with water. The degreased aluminum plate was immersed in a 10 wt% sulfuric acid aqueous solution kept at 25 ° C. for 5 seconds, desmutted, and washed with water.

Next, while supplying a dispersion liquid in which an abrasive (alumina # 800) was dispersed in water at a concentration of 20% by weight to this aluminum plate at a supply rate of 20 liters / min,
Brush polishing was carried out at a brush rotation speed of 240 rpm and a conveying speed of 2.0 m / min for mechanical roughening.

Then, it was immersed in a 10% by weight sodium hydroxide aqueous solution kept at 70 ° C. for 10 seconds, then in a 10% by weight sulfuric acid aqueous solution kept at 25 ° C. for 10 seconds, desmutted, and washed with water. did.

Then, this aluminum plate was used as an electrolytic solution in a 1% by weight hydrochloric acid aqueous solution and subjected to a sinusoidal alternating current of 60 Hz at a temperature of 25 ° C., a current density of 50 A / dm ² , and an electric power of 300 C.
After electrolytic surface-roughening treatment under the condition of / dm ² , it is immersed in a 30 wt% sulfuric acid aqueous solution kept at 60 ° C for 30 seconds, and mainly contains aluminum hydroxide produced by electrolytic surface-roughening treatment. The smut component was removed.

With respect to the roughened aluminum plate thus obtained, the average diameter of the pit openings and the direction perpendicular to the pit diameter were described in the same manner as described in [Preparation of support 3-1]. When the average depth was determined, the average diameter of the pit openings was 3.3 μm, and the average depth in the direction perpendicular to the pit diameter was 0.91 μm. In addition, sharp parts (pit edges) formed between pits of 0.5 μm or more were also observed.

This aluminum plate was kept at 40 ° C. 6
Alkaline etching was performed for 5 seconds in a weight% sodium hydroxide aqueous solution. Then, anodization treatment was performed for 1 minute in a 20 wt% sulfuric acid aqueous solution at a temperature of 35 ° C. and a current density of 3 A / dm ² . After that, it was immersed in a 0.1% by weight ammonium acetate aqueous solution kept at 80 ° C for 30 seconds for sealing treatment,
The support 3-4 was obtained after drying at 80 ° C. for 5 minutes.

Regarding the roughened support thus obtained, in the same manner as described in [Preparation of support 3-1], a portion sandwiched by pits of 0.5 μm or more was randomly selected. As a result of selecting and observing 50 places, 92% of the parts were found to have the average diameter 3.3 μm of the pit openings of the concave pits of the roughened aluminum plate and the average in the direction perpendicular to the pit diameter according to the formula 1. The radius of curvature was within the range of the radius of curvature (0.002-0.114 μm) calculated by substituting the depth of 0.91 μm.

The surface roughness Ra of the support is 0.62 μm.
m and Rz were 3.76 μm, and the area A was 124.3 μm ² .

[Preparation of Support 3-5] An aluminum plate having a thickness of 0.3 mm (material JIS standard A1050, temper H16)
It was immersed in a 6 wt% sodium hydroxide aqueous solution kept at 0 ° C, degreased for 12 seconds, and then washed with water. The degreased aluminum plate was immersed in a 10 wt% sulfuric acid aqueous solution kept at 25 ° C. for 5 seconds, desmutted, and washed with water.

Next, this aluminum plate was used as an electrolytic solution in a 2% by weight aqueous nitric acid solution and subjected to a sinusoidal alternating current of 60 Hz at a temperature of 25 ° C., a current density of 30 A / dm ² , and an electric power of 800 C.
After electrolytic surface-roughening treatment under the condition of / dm ² , it is immersed in a 30 wt% sulfuric acid aqueous solution kept at 60 ° C for 30 seconds, and mainly contains aluminum hydroxide produced by electrolytic surface-roughening treatment. The smut component was removed.

With respect to the roughened aluminum plate thus obtained, the average diameter of the pit openings and the direction perpendicular to the pit diameter were described in the same manner as described in [Preparation of support 3-1]. When the average depth was determined, the average diameter of the pit openings was 1.7 μm, and the average depth in the direction perpendicular to the pit diameter was 0.95 μm. In addition, sharp parts (pit edges) formed between pits of 0.5 μm or more were also observed.

This aluminum plate was kept at 25 ° C. 6
Alkaline etching was performed for 5 seconds in a weight% sodium hydroxide aqueous solution. Then, anodization treatment was performed for 1 minute in a 20 wt% sulfuric acid aqueous solution at a temperature of 35 ° C. and a current density of 3 A / dm ² . After that, it was immersed in a 0.1% by weight ammonium acetate aqueous solution kept at 80 ° C for 30 seconds for sealing treatment,
The support 3-5 was obtained after drying at 80 ° C. for 5 minutes.

Regarding the roughened support thus obtained, in the same manner as described in [Preparation of support 3-1], a portion sandwiched by pits of 0.5 μm or more was randomly selected. As a result of selecting and observing 50 locations, the 9% portion was found to be the average diameter 1.7 μm of the pit opening of the concave pits of the roughened aluminum plate and the average in the direction perpendicular to the pit diameter in Equation 1 above. The radius of curvature was within the range of the radius of curvature (0.012-0.173 μm) calculated by substituting the depth of 0.95 μm.

The surface roughness Ra of the support is 0.65 μm.
m and Rz were 3.38 μm, and the area A was 128.4 μm ² .

[Preparation of support 3-6] An aluminum plate having a thickness of 0.3 mm (material JIS standard A1050, temper H16)
It was immersed in a 6 wt% sodium hydroxide aqueous solution kept at 0 ° C, degreased for 12 seconds, and then washed with water. The degreased aluminum plate was immersed in a 10 wt% sulfuric acid aqueous solution kept at 25 ° C. for 5 seconds, desmutted, and washed with water.

Next, this aluminum plate was used as an electrolytic solution in a 1% by weight hydrochloric acid aqueous solution and subjected to a sinusoidal alternating current of 60 Hz at a temperature of 25 ° C., a current density of 50 A / dm ² , and an electric current of 400 C.
After electrolytic surface-roughening treatment under the condition of / dm ² , it is immersed in a 30 wt% sulfuric acid aqueous solution kept at 60 ° C for 30 seconds, and mainly contains aluminum hydroxide produced by electrolytic surface-roughening treatment. The smut component was removed.

With respect to the roughened aluminum plate thus obtained, the average diameter of the pit openings and the direction perpendicular to the pit diameter were described in the same manner as described in [Preparation of support 3-1]. When the average depth was determined, the average diameter of the pit openings was 5.3 μm, and the average depth in the direction perpendicular to the pit diameter was 1.30 μm. In addition, sharp parts (pit edges) formed between pits of 0.5 μm or more were also observed.

This aluminum plate was kept at 40 ° C. 6
Alkaline etching was performed for 7 seconds in a weight% sodium hydroxide aqueous solution. Then, anodization treatment was performed for 1 minute in a 20 wt% sulfuric acid aqueous solution at a temperature of 35 ° C. and a current density of 3 A / dm ² . After that, it was immersed in a 0.1% by weight ammonium acetate aqueous solution kept at 80 ° C for 30 seconds for sealing treatment,
The support 3-6 was obtained after drying at 80 ° C. for 5 minutes.

Regarding the roughened support thus obtained, in the same manner as described in [Preparation of support 3-1], a portion sandwiched by pits of 0.5 μm or more was randomly selected. As a result of selecting and observing 50 places, 97% of the parts were found to have the average diameter of 5.3 μm in the pit opening of the concave pits of the roughened aluminum plate and the average in the direction perpendicular to the pit diameter in Equation 1 above. The radius of curvature was within the range (0.001 to 0.184 μm) of the radius of curvature calculated by substituting the depth of 1.30 μm.

The surface roughness Ra of the support is 0.65 μm.
m and Rz were 3.95 μm, and the area A was 300.3 μm ² .

[Preparation of Support 3-7] An aluminum plate having a thickness of 0.3 mm (material JIS standard A1050, temper H16)
It was immersed in a 6 wt% sodium hydroxide aqueous solution kept at 0 ° C, degreased for 12 seconds, and then washed with water. The degreased aluminum plate was immersed in a 10 wt% sulfuric acid aqueous solution kept at 25 ° C. for 5 seconds, desmutted, and washed with water.

Next, while supplying a dispersion liquid in which an abrasive (alumina # 800) was dispersed in water at a concentration of 20% by weight to this aluminum plate at a supply rate of 20 liters / min,
Brush polishing was carried out at a brush rotation speed of 240 rpm and a conveying speed of 2.0 m / min for mechanical roughening.

Then, it was immersed in a 10% by weight sodium hydroxide aqueous solution kept at 70 ° C. for 10 seconds, then in a 10% by weight sulfuric acid aqueous solution kept at 25 ° C. for 10 seconds, desmutted, and washed with water. did.

Then, using this aluminum plate in a 2 wt% nitric acid aqueous solution as an electrolytic solution, a temperature of 25 ° C., a current density of 30 A / dm ² , and an electric power of 200 C were applied by a sinusoidal alternating current of 60 Hz.
After electrolytic surface-roughening treatment under the condition of / dm ² , it is immersed in a 30 wt% sulfuric acid aqueous solution kept at 60 ° C for 30 seconds, and mainly contains aluminum hydroxide produced by electrolytic surface-roughening treatment. The smut component was removed.

With respect to the roughened aluminum plate thus obtained, the average diameter of the pit openings and the direction perpendicular to the pit diameter were described in the same manner as described in [Preparation of support 3-1]. When the average depth was determined, the average diameter of the pit openings was 1.2 μm, and the average depth in the direction perpendicular to the pit diameter was 0.57 μm. In addition, a sharp part (pit edge) formed between pits of 0.5 μm or more
Was also observed.

This aluminum plate was kept at 85 ° C. 6
Alkaline etching was performed for 30 seconds in a weight% sodium hydroxide aqueous solution. Then, anodization treatment was performed for 1 minute in a 20 wt% sulfuric acid aqueous solution at a temperature of 35 ° C. and a current density of 3 A / dm ² . After that, it was immersed in a 0.1% by weight ammonium acetate aqueous solution kept at 80 ° C for 30 seconds for sealing treatment,
The support 3-7 was obtained after drying at 80 ° C. for 5 minutes.

With respect to the roughened support thus obtained, in the same manner as described in [Preparation of support 3-1], a portion sandwiched by pits of 0.5 μm or more was randomly selected. As a result of selecting and observing 50 spots in the above, 60% of the parts were found to have the average diameter 1.2 μm of the pit openings of the concave pits of the roughened aluminum plate and the average in the direction perpendicular to the pit diameter in Equation 1 above. The radius of curvature was within the range of radius of curvature (0.010 to 0.074 μm) calculated by substituting the depth of 0.57 μm.

The surface roughness Ra of the support is 0.78 μm.
m and Rz were 4.25 μm, and the area A was 159.6 μm ² .

[Preparation of support 3-8] An aluminum plate having a thickness of 0.3 mm (material JIS standard A1050, temper H16)
It was immersed in a 6 wt% sodium hydroxide aqueous solution kept at 0 ° C, degreased for 12 seconds, and then washed with water. The degreased aluminum plate was immersed in a 10 wt% sulfuric acid aqueous solution kept at 25 ° C. for 5 seconds, desmutted, and washed with water.

Next, while supplying a dispersion liquid in which an abrasive (alumina # 800) was dispersed in water at a concentration of 20% by weight to this aluminum plate at a supply rate of 20 liters / min,
Brush polishing was carried out at a brush rotation speed of 240 rpm and a conveying speed of 2.0 m / min for mechanical roughening.

After that, it was immersed in a 10 wt% sodium hydroxide aqueous solution kept at 70 ° C. for 10 seconds, then in a 10 wt% sulfuric acid aqueous solution kept at 25 ° C. for 10 seconds, desmutted, and washed with water. did.

Next, this aluminum plate was used as an electrolytic solution in a 1 wt% hydrochloric acid aqueous solution, and was subjected to a sinusoidal alternating current of 60 Hz at a temperature of 25 ° C., a current density of 50 A / dm ² , and an electric power of 300 C.
After electrolytic surface-roughening treatment under the condition of / dm ² , it is immersed in a 30 wt% sulfuric acid aqueous solution kept at 60 ° C for 30 seconds, and mainly contains aluminum hydroxide produced by electrolytic surface-roughening treatment. The smut component was removed.

With respect to the roughened aluminum plate thus obtained, the average diameter of the pit openings and the direction perpendicular to the pit diameter were described in the same manner as described in [Preparation of support 3-1]. When the average depth was determined, the average diameter of the pit openings was 3.3 μm, and the average depth in the direction perpendicular to the pit diameter was 0.91 μm. In addition, sharp parts (pit edges) formed between pits of 0.5 μm or more were also observed.

This aluminum plate was anodized in a 20% by weight aqueous sulfuric acid solution at a temperature of 35 ° C. and a current density of 3 A / dm ² for 1 minute. Then, it was immersed in a 0.1 wt% ammonium acetate aqueous solution kept at 80 ° C. for 30 seconds for sealing treatment, and dried at 80 ° C. for 5 minutes to obtain a support 3-8.

With respect to the roughened support thus obtained, in the same manner as described in [Preparation of support 3-1], a part sandwiched by pits of 0.5 μm or more was randomly selected. After selecting and observing 50 locations,
, The radius of curvature calculated by substituting the average diameter 3.3 μm of the pit opening of the concave pit of the roughened aluminum plate and the average depth 0.91 μm in the direction perpendicular to the pit diameter (0.002 to 0.114 There was no sharp portion (pit edge) with a radius of curvature falling in the range of μm).

The surface roughness of the support is such that Ra is 0.65 μm.
m and Rz were 3.82 μm, and the area A was 104.2 μm ² .

Table 5 shows the main production conditions of the supports 3-1 to 3-8, the average diameter of the pit openings after the electrolytic graining treatment, the average depth in the direction perpendicular to the pit diameter, 0.5. Sharp part formed between pits of μm or more (pit edge)
The presence or absence, the range of the radius of curvature, the ratio of sharp portions (pit edges) having the radius of curvature included in the range of the radius of curvature after the alkali etching, Ra, Rz, and the area A are shown.

[0257]

[Table 5]

[Preparation of Photosensitive Planographic Printing Plate Samples 3-1 to 3-8] A positive type photosensitive composition coating liquid having the following composition was applied onto a support 3-1 to 3-8 using a wire bar. And 80 ℃
After drying for 2 minutes, the photosensitive lithographic printing plate samples 3-1 to 3-8
It was created. The coating amount of the positive photosensitive composition coating liquid was set to 2.0 g / m ² as a dry weight.

<Positive Photosensitive Composition Coating Liquid> (Photosensitive liquid) Novolac resin (phenol / m-cresol / p-cresol molar ratio 10/54/36, weight average molecular weight 4000) 6.70 g pyrogallolacetone resin ( Condensation product of weight average molecular weight 3000) and o-naphthoquinonediazide-5-sulfonyl chloride (esterification rate 30%) 1.50 g Polyethylene glycol # 2000 0.20 g Victoria Pure Blue BOH (Hodogaya Chemical Co., Ltd.) 0.080 g 2,4 -Bis (trichloromethyl) -6- (p-methoxystyryl) -s-triazine 0.15 g FC-430 (Sumitomo 3M Ltd.) 0.03 g cis-1,2-cyclohexanedicarboxylic acid 0.20 g methyl cellosolve 100 ml

Obtained photosensitive lithographic printing plate samples 3-1 to 3-3
With respect to -8, printing durability, full-face stain recovery, blanket stain and developability were evaluated by the following evaluation methods.

[Evaluation Method] <Evaluation of Printing Durability> A 4 kW metal halide lamp was used as a light source, and image exposure was carried out by irradiating at 8 mW / cm ² for 60 seconds. The exposed photosensitive lithographic printing plate was developed with a commercially available developer [SDR-1 (manufactured by Konica Corporation) diluted 6 times] at a developing time of 20 seconds and a developing temperature of 27 ° C.

The lithographic printing plate thus obtained was applied to a printing machine (DAIYAlF-1 manufactured by Mitsubishi Heavy Industries, Ltd.), and coated paper, dampening water (etching solution SG-51 manufactured by Tokyo Ink Co., Ltd. concentration: 1.
5%), ink (High Plus M manufactured by Toyo Ink Mfg. Co., Ltd.)
(Red) was used for printing, and printing was performed until defective ink buildup appeared in the image area of the printed matter or ink adhered to the non-image area.The number of printed sheets at that time was counted, and the printing durability was evaluated by this number. . <Evaluation of recovery property of entire surface stain> Using a lithographic printing plate obtained in the same manner as in the evaluation of printing durability, under the same printing conditions,
Start printing after applying ink to the entire surface of the lithographic printing plate to count it and count the number when a clean and complete image is obtained.
This number was used to stain the entire surface and to evaluate the recoverability.

<Evaluation of stain on blanket> Using a lithographic printing plate obtained in the same manner as in the evaluation of printing durability, printing was performed under the same printing conditions, and when 10,000 sheets were printed, the printing machine was stopped and the blanket was printed. The degree of stain of ink on the non-image area was visually observed, and the stain on the blanket was evaluated according to the following evaluation criteria.

◯: Almost no stain.

X: Remarkably soiled.

<Evaluation of Developability> A 4 kW metal halide lamp was used as a light source, and image exposure was carried out by irradiating at 8 mW / cm ² for 60 seconds. This exposed photosensitive lithographic printing plate was developed with a commercially available developer [SDR-1 (manufactured by Konica Corporation) diluted 12 times] at a developing time of 20 seconds and a developing temperature of 27 ° C.

Using the obtained lithographic printing plate, under the same printing conditions as in the above evaluation of printing durability, ink was applied to the entire surface of the lithographic printing plate to stain it, and printing was started to obtain a clean and complete image. The number of sheets to be counted was counted and this number was evaluated.

Table 6 shows the obtained evaluation results.

[0269]

[Table 6]

[0270]

EFFECTS OF THE INVENTION The pit structure of the concave pits on the rough surface has a pit structure of secondary or higher, and the upper projected area of the pits of the maximum order occupying the upper projected area of the entire concave pits on the rough surface is The support of the present invention having a value of 0.7 or more has excellent printing durability, and a photosensitive lithographic printing plate that is resistant to stains can be obtained, and the average diameter of the openings of the concave pits on the rough surface is 1.0 μm or less. The support of the present invention having pits, the ratio of the primary pits present alone to the concave pits on the rough surface is 80.
% Or more of the support of the present invention, the primary projection of the primary pit in the upper projection area of the primary pit occupying the upper projection area of the whole concave pit is 0.5 or more, the primary pit of the concave pit of the rough surface is The support of the present invention having a linear gradient of 0.3 or more by linear regression analysis of "pit diameter" and "maximum depth in the direction perpendicular to the diameter" is excellent in small point reproducibility and K value,
In addition, it is possible to obtain a photosensitive lithographic printing plate that does not easily get dirty,
The surface roughness of the rough surface is Ra of 0.6 μm or more and 0.9 μm or less, Rz
Is 3.5 μm or more and 6.0 μm or less, and the pit edge formed by sandwiching between pits with an opening diameter of 0.5 μm or more formed by electrochemical surface roughening is dissolved by alkali etching, and the shape of the sharp part is formed. 70% or more of the anodized support of the present invention having a radius of curvature within the range of the radius of curvature calculated by the formula A has good developability of the non-image area, It is possible to obtain a photosensitive lithographic printing plate which is less likely to cause stains and stains on the blanket and has excellent printing durability.

[Brief description of drawings]

FIG. 1 is an explanatory diagram for explaining the order of a pit structure.

FIG. 2 is an explanatory diagram for explaining a change in pit shape due to alkali etching.

FIG. 3 is an explanatory diagram for explaining the diameter of the opening portion of the concave pit used for obtaining the average diameter of the opening portion of the concave pit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Aluminum support 2 Primary pit 3 Secondary pit 11 Sharp part 12 Tip part which has spherical surface 13 c Maximum length of opening of concave pit d Maximum length of width of opening of concave pit

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical indication location G03F 7/00 503 G03F 7/00 503 (72) Inventor Nozomi Kojima 1 Sakuramachi, Hino City, Tokyo Konica Stock Company (72) Inventor Nobuyuki Ishii No. 1 Sakura-cho, Hino City, Tokyo Konica Stock Company (72) Inventor Yasuhisa Sugi No. 1 Sakura-cho, Hino City, Tokyo Konica Stock Company

Claims (8)

[Claims] 1. An aluminum support that has been roughened and anodized, wherein the pit structure of the concave pits on the rough surface has a pit structure of a secondary or higher degree, and has a maximum relative to the apparent area. The upper projected area ratio of the order pit is
An aluminum support for a lithographic printing plate, characterized by having 0.7 or more. 2. A roughened and anodized aluminum support, wherein the roughened surface has concave pits, and the average diameter of the pit openings of the concave pits is 1.0.
An aluminum support for a lithographic printing plate characterized by having a thickness of at most μm. 3. A roughened and anodized aluminum support, wherein the rough surface has concave pits, and the "pit diameter" of the primary pit and the maximum in the direction perpendicular to the diameter. Depth 'linear regression analysis yields a slope of 0.3
It is above, The aluminum support for lithographic printing plates of Claim 2 characterized by the above-mentioned. 4. A roughened and anodized aluminum support, wherein the roughened surface has concave pits and is present independently of the entire primary pits without being included in secondary or higher pits. An aluminum support for a lithographic printing plate, wherein the ratio of primary pits is 80% or more. 5. A roughened and anodized aluminum support, wherein the roughened surface has concave pits and is present alone without being included in secondary or higher pits with respect to the apparent area. The upper projected area ratio of the primary pit is 0.5
An aluminum support for a lithographic printing plate characterized by the above. 6. A surface-roughened and anodized aluminum support is formed by sandwiching pits having an opening diameter of 0.5 μm or more among concave pits formed by electrochemical surface-roughening. The sharp part that can be confirmed when observing the formed part from the cross section is dissolved by alkali etching, and after alkali etching, observe the part sandwiched between concave pits with an opening diameter of 0.5 μm or more, 70% or more of which is electric It is characterized in that it has a radius of curvature calculated by the following formula 1 from the average depth of the concave pits formed by chemical roughening in the direction perpendicular to the pit diameter and the average diameter of the pit openings. Aluminum support for lithographic printing plates. [Equation 1] 7. A roughened and anodized aluminum support, 1 μm from the apex of the third highest peak of a two-dimensional surface roughness curve having a measurement length of 0.5 mm on the surface of the support.
The total area of the figure formed by the reference straight line drawn in parallel with the center line of the roughness below and the roughness curve above the reference straight line is
An aluminum support for a lithographic printing plate according to claim 6, wherein a is 50 [mu] m ² or more 150 [mu] m ² or less. 8. A photosensitive lithographic printing plate comprising the aluminum support for a lithographic printing plate according to claim 1 provided with a layer of a photosensitive composition.