JPH11180063A - Starter solution for lithographic printing plate and printing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a starter solution capable of enhancing ink receiving properties at the time of starting a printing process, in a lithographic printing plate using an image silver for its ink receiving properties. SOLUTION: This starter solution is used for treating the printing face of the lithographic printing plate which uses an image silver for its ink receiving properties at the time of starting a printing process. The starter solution contains at least, one kind selected from an amine compound with a propylene oxy group and an ethylene oxy group, a fatty acid amide compound with the propylene oxy group and the ethylene oxy group and a quaternary ammonium compound with the propylene oxy group and the ethylene oxy group.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a starter liquid used at the start of printing of a lithographic printing plate utilizing image silver as ink receptivity, and a printing method using the same.

[0002]

2. Description of the Related Art A lithographic printing plate in which a transferred silver image obtained by a silver complex salt diffusion transfer method (DTR method) can be immediately used as ink acceptability is already known. Part 1
One type is a lithographic printing plate having, in this order, at least a silver halide emulsion layer and a physical development nucleus layer on a support (eg, a paper base coated with a polyethylene resin, a polyethylene terephthalate base, etc.), for example, US Pat. No. 3,721,559. No. 3490905, No. 33
No. 85701, No. 3814603, No. 34543
No. 98, No. 3764323, No. 3099209
No., JP-B-44-27242, 48-30562
No., JP-A-53-9603, JP-A-53-21602,
Nos. 54-103104 and 56-9750.

The above lithographic printing plate has a physical development nucleus on the surface of the emulsion layer using gelatin as a binder, and the silver halide crystals in the exposed emulsion layer undergo chemical development by DTR development to become black silver. To form a hydrophilic non-image portion mainly composed of gelatin. On the other hand, unexposed silver halide crystals are converted into a silver salt complex by the silver salt complexing agent in the developing solution and diffused to the physical development nucleus layer on the surface. An image portion mainly composed of physically developed silver is formed.

[0004] Here, the silver image portion has an ink receptivity.
The gelatin surface in the non-image area is subjected to printing as ink repellency. Although the gelatin surface itself was hydrophilic, it was not sufficient in terms of water retention.

[0005] Another type is a lithographic printing plate having a silver halide emulsion layer on a physical development nucleus supported on a roughened and anodized aluminum support (hereinafter referred to as an aluminum lithographic printing plate). Are known, for example,
-216236, and JP-A-6-81194. After exposure and development of this lithographic printing plate, the silver halide emulsion layer is washed off (washed off), and an image portion composed of a metallic silver film and a non-image portion composed of an aluminum anodized surface appear.

Although the two lithographic printing plates differ in construction and plate making method, they are common in making the image silver ink receptive. These lithographic printing plates are composed of an image portion that receives oily ink and a non-image portion that is hydrophilic and receives water. Thus, normal lithographic printing supplies both water (humidifying liquid) and ink to the printing plate, the image portion selectively receives color ink, the non-image portion selectively receives water, and the ink on the image is, for example, received. This is done by transferring it to a substrate such as paper.

In order to obtain good printed matter, it is required that the difference between the lipophilicity and the hydrophilicity of the surface of the image portion and the non-image portion is sufficiently large. For this reason, it has been known that a compound having a mercapto group or a thione group is allowed to act on a silver image on a plate surface for the purpose of enhancing the ink receptivity of an image area formed by physically developed silver (for example, Japanese Patent Publication No. 48-148). 29
723 and JP-A-58-127928).

On the other hand, in order to prevent stains due to ink adhesion to the non-image area at the start of printing, it is also essential to wet the printing plate surface so that the printing plate can easily receive the humidifier during printing. In particular, in the former lithographic printing plate (type in which the gelatin film forms a non-image portion), it is important that the non-image portion has insufficient water retention and that the plate surface is wet at the start of printing.

Therefore, in the former lithographic printing plate, a treatment liquid containing inorganic fine particles such as colloidal silica was applied to the plate surface as a starter liquid immediately before the start of printing. Further, the starter liquid contains a compound having a mercapto group or a thione group in order to improve the ink receptivity of the image area.

In the present invention, as described above, the starter liquid is a processing liquid applied to the printing plate immediately before the start of printing. The starter solution is generally used between the time when the printing plate is mounted (plated) on the printing press and the time when printing is started. In short, it is used so that the plate surface can be kept wet with water when printing is started.

On the other hand, the latter aluminum lithographic printing plate is
Since the non-image area was formed on the anodized surface of aluminum, the water retention performance was high, and the above-described starter liquid was not used.

However, in the case of aluminum lithographic printing plates, the conventional methods have not been sufficient to realize higher ink receptivity at the start of printing. For aluminum lithographic printing plates, the quality of the emulsion layer removal (wash-off) during the rinsing step during plate making affects printability, especially ink acceptability at the start of printing. Etc.) and variations in the initial printability of the running process.

[0013] Similarly, the former lithographic printing plate also suffers from running fatigue of a plate making solution such as a developing solution or a stabilizing solution.
There was a problem that ink acceptability was reduced. JP 8
JP-A-82935 discloses that a plate surface treatment liquid containing a compound having an ethyleneoxy group improves ink receptivity. However, it has not yet been possible to stably and sufficiently improve the ink receptivity, which has been reduced by the running process of the plate making process.

[0014]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a lithographic printing plate utilizing image silver as ink receptivity, thereby stably and sufficiently improving the ink receptivity of a silver image portion at the start of printing. It is to provide a starter liquid that can be used.

[0015]

SUMMARY OF THE INVENTION The above objects of the present invention are as follows.
A starter liquid for processing the plate surface of a lithographic printing plate using image silver as ink acceptability at the start of printing,
Contains at least one selected from an amine compound having a propyleneoxy group and an ethyleneoxy group, a fatty acid amide compound having a propyleneoxy group and an ethyleneoxy group, and a quaternary ammonium compound having a propyleneoxy group and an ethyleneoxy group. This was achieved by a starter solution characterized by:

In the present invention, as described above, the starter liquid is a processing liquid for making the printing plate surface wet with water immediately before the start of printing. The starter solution is used between the time when the printing plate is mounted on the printing press (printing) and the start of printing, or immediately before the printing. Usually, a printing plate is mounted on a printing press before use.

The compound used in the present invention can stably and sufficiently reduce the ink receptivity reduced by the running treatment of a plate-making processing solution with respect to the compound known in JP-A-8-82935. It was found to improve.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
The compound used in the present invention has a propyleneoxy group (P
An amine compound having a group in which a block of O or O) and an ethyleneoxy group (EO group) are randomly or randomly polymerized; a fatty acid amide compound having a group in which a PO or EO group is blocked or randomly polymerized; or a block of a PO or EO group Alternatively, it is a quaternary ammonium compound having a randomly polymerized group. The polymerization ratio of the PO group and the EO group is from 1: 9 to
5: 5 is preferred. The PO group and the EO group are each contained in the range of 1 to 60 per molecule. Preferably, 2 to 40 are required respectively. Hereinafter, a specific description will be given.

Representative amine compounds having a PO group and an EO group are represented by the following general formula.

[0020]

Embedded image In the formula, R ₁ and R ₂ represent an aliphatic group or a group in which an EO group and a PO group are polymerized, and m and n each represent a repeating unit of an EO group or a PO group.

More specifically, examples of the aliphatic group include an alkyl group, an alkenyl group, and an alkynyl group. These aliphatic groups may be substituted with an amino group or the like. Further, the amino group may be substituted with an aliphatic group, or a group obtained by polymerizing an EO group and a PO group may be added. Preferably, _one of R ₁ and R ₂ is E
O and PO groups are polymerized groups, the other of which has 4 to 1 carbon atoms.
8 aliphatic groups. Specific compounds are described below.

[0022]

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[0023]

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[0024]

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[0025]

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Next, a fatty acid amide compound having a PO group and an EO group will be described. Representative compounds are represented by the following general formula.

[0027]

Embedded image In the formula, R ₃ represents an aliphatic group, and R ₄ represents an aliphatic group or EO
It represents a group in which a group and a PO group are polymerized. m and n have the same meanings as in Chemical formula 1.

More specifically, examples of the aliphatic group for R ₃ include an alkyl group, an alkenyl group, and an alkynyl group. These aliphatic groups preferably have about 4 to 18 carbon atoms. Examples of the aliphatic group for R ₄ include an alkyl group, an alkenyl group, and an alkynyl group. R ₄ is preferably a group obtained by polymerizing an EO group and a PO group. Specific compounds are described below.

[0029]

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[0030]

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Next, a quaternary ammonium compound having a PO group and an EO group will be described. Representative compounds are represented by the following general formula.

[0032]

Embedded image In the formula, R ₅ has the same meaning as R ₃ , R ₆ and R ₇ have the same meaning as R ₄ , and m and n have the same meanings as in Chemical formula 1. Preferred compounds in the chemical formula 9 are those wherein R ₅ is an aliphatic group having 4 to 18 carbon atoms, R ₆ and R
₇ is a group obtained by polymerizing an EO group and a PO group. Specific compounds are described below.

[0033]

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[0034]

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The compound having a PO group and an EO group is contained in an amount of 0.1 to 20 g, preferably 0.2 to 10 g, per liter of the starter solution.

The starter solution of the present invention preferably further contains a compound having a mercapto group or a thione group as a compound (hydrophobizing agent) for making image silver hydrophobic, as disclosed in JP-B-48-29723, JP-A-48-29723. 1958-1279
Those described in No. 28 and the like are preferable. Particularly, a nitrogen-containing heterocyclic compound is preferable. This further improves the ink acceptability of the silver image portion.

Representative examples of the nitrogen-containing heterocyclic compound having a mercapto group or a thione group include those having a general formula shown in the following chemical formula 1.

[0038]

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(Wherein R ₁ and R ₃ are an alkyl group, alkenyl group, aralkyl group or aryl group having 3 or more carbon atoms, preferably 3 to 12 carbon atoms, and R ₂ is a hydrogen, an alkyl group, an alkenyl group or an aralkyl group). Or an aryl group.
n represents an integer of 1 or more. When R ₂ is an alkyl group, alkenyl group, aralkyl group or aryl group having 3 or more carbon atoms, n may be 0. Z is N, C in the formula
And the remaining atomic groups of the bond necessary to form a 5- or 6-membered ring with the above. )

Specific examples of the 5- or 6-membered ring include imidazole, imidazoline, thiazole, thiazoline,
Oxazole, oxazoline, pyrazoline, triazole, thiadiazole, oxadiazole, tetrazole, pyridine, pyrimidine, pyridazine, pyrazine, triazine, etc., and these rings may be two or more condensed rings; And those condensed with a naphthalene ring. Further, it is preferable that the compound does not have a water-soluble group such as a carboxy group and a sulfo group.

Specific examples of such compounds include 2-mercapto-4-phenylimidazole and 2-mercapto-1
-Benzylimidazole, 2-mercapto-1-butyl-benzimidazole, 1,3-dibenzyl-imidazolidin-2-thione, 2-mercapto-4-phenylthiazole, 3-butyl-benzothiazoline-2-thione, 3- Dodecyl-benzothiazoline-2-thione, 2
-Mercapto-4,5-diphenyloxazole, 3-
Pentyl-benzoxazoline-2-thione, 1-phenyl-3-methylpyrazolin-5-thione, 3-mercapto-4-allyl-5-pentadecyl-1,2,4-triazole, 3-mercapto-5-nonyl-1 , 2,4
-Triazole, 3-mercapto-4-acetamide-5
-Heptyl-1,2,4-triazole, 3-mercapto-4-amino-5-heptadecyl-1,2,4-triazole, 2-mercapto-5-phenyl-1,3,4
-Thiadiazole, 2-mercapto-5-n-heptyl-oxathiazole, 2-mercapto-5-nheptyl-oxadiazole, 2-mercapto-5-phenyl-
1,3,4-oxadiazole, 2-heptadecyl-5
-Phenyl-1,3,4-oxadiazole, 5-mercapto-1-phenyl-tetrazole, 3-mercapto-4-methyl-6-phenyl-pyridazine, 2-mercapto-5,6-diphenyl-pyrazine, -Mercapto-4,6-diphenyl-1,3,5-triazine, 2-
Amino-4-mercapto-6-benzyl-1,3,5-
Examples include, but are not limited to, triazines.

The amount of the compound having a mercapto group or a thione group to be used is 0.1 to 1 liter of the starter solution.
The amount is from 01 to 10 g, but preferably from 0.02 to 5 g.

It is preferable that the starter liquid of the present invention also has a function as a plate cleaner. That is, a function of removing ink on the printing plate surface is provided when stains occur during printing or when storing a printing plate after printing. To impart this function, various solvents, for example, alkylbenzene, or glycols such as propylene glycol, dipropylene glycol, tripropylene glycol, hexylene glycol, polyoxyethylene polyoxypropylene alkyl ether, or a nonionic surfactant It is preferable to include them.

The aluminum lithographic printing plate preferably has a function as a plate reservoir. That is, in order to preserve the printing plate once subjected to printing and use it again for printing, to protect the plate surface, gum arabic, dextrin, sodium alginate, polystyrene sulfonic acid, carboxymethyl cellulose,
It is preferable to contain a polymer such as polyvinyl alcohol.

The starter liquid of the present invention may contain, in addition to the above compounds, commonly used preservatives, preservatives and the like. For example, chelating agents such as iminodiacetic acid and ethylenediaminetetraacetic acid can be mixed.

Further, in order to improve the rust prevention of the starter liquid, phosphoric acid or a phosphate and an amine compound can be contained.

When the starter solution of the present invention is applied to the former lithographic printing plate having a gelatin film as a non-image portion, it is preferable to further contain inorganic fine particles such as colloidal silica. Thereby, the water retention of the non-image portion is improved.

The starter liquid of the present invention is applied to a lithographic printing plate utilizing a metallic silver image portion as ink acceptability.
The planographic printing plates are roughly classified into two types as described above. One type is a lithographic printing plate in which an undercoat layer also serving as an antihalation layer, a silver halide emulsion layer, and a physical development nucleus layer are applied in this order on a paper base or polyethylene terephthalate film base coated with a polyethylene resin. It is.

In the second type, a physical development nucleus is supported on a roughened and anodized aluminum support,
This is a lithographic printing plate on which a halogenated emulsion layer is provided. A lithographic printing plate having an intermediate layer suitably provided between a physical development nucleus and a silver halide emulsion layer may be used.

The silver halide emulsion used in the lithographic printing plate of the present invention includes silver chloride, silver bromide, silver iodide, silver chlorobromide, silver chloroiodobromide, and silver iodobromide. Although silver chloride is mainly used (meaning silver chloride of 50 mol% or more) is preferable. The emulsion type may be either a negative type or a positive type. These silver halide emulsions can be chemically or spectrally sensitized as necessary.

Gelatin is preferably used as the hydrophilic colloid in the silver halide emulsion layer when preparing silver halide grains. Various gelatins such as acid-treated gelatin and alkali-treated gelatin can be used as the gelatin.
Further, those modified gelatins (for example, phthalated gelatin, amidated gelatin, etc.) can also be used. Further, hydrophilic polymer compounds such as polyvinylpyrrolidone, various starches, albumin, polyvinyl alcohol, gum arabic, and hydroxyethyl cellulose can be contained.

In the former lithographic printing plate having a gelatin layer as a non-image portion, a silver halide emulsion layer containing gelatin and an undercoat layer contain a gelatin crosslinking agent (hardener) to form a strong gelatin film. Need to be formed. On the other hand, in the latter aluminum lithographic printing plate, since the silver halide emulsion layer and the like are removed and the aluminum surface is exposed to form a non-image portion, the hydrophilic colloid used in the silver halide emulsion layer is substantially Desirably does not contain a hardener.

The aluminum support used in the present invention is a roughened and anodized aluminum plate, preferably the one described in US Pat. No. 5,427,889.

The physical development nucleus of the physical development nucleus layer used in the present invention may be a physical development nucleus used for a known silver complex salt diffusion transfer method, for example, a colloid of gold, silver or the like, or a water-soluble salt of palladium, zinc or the like. Metal sulfide mixed with sulfide can be used. Various hydrophilic colloids can be used as the protective colloid. For details and manufacturing method,
For example, Focal Press, London New York (1972), Andre Lott and Edith
See Weide, "Photographic Silver Halide Diffusion Processes".

[0055]

EXAMPLES The present invention will be described below with reference to examples, but is of course not limited thereto.

Example 1 As a lithographic printing plate utilizing a silver complex salt diffusion transfer method, a matted layer containing silica particles having an average particle size of 5 μm was provided on one surface of a subbed-treated polyester film support. Antihalation undercoat layer containing carbon black on the surface and silica powder having an average particle size of 3.5 μm at 20% by weight based on photographic gelatin (adjusted to pH 4)
High-sensitivity silver chloride emulsion (adjusted to pH 4) spectrally sensitized in the green region containing 5% by weight of silica powder having an average particle size of 3.5 μm with respect to photographic gelatin after chemical sensitization. And provided.

The gelatin of the undercoat layer was applied at a rate of 3.5 g / m ² , the gelatin of the emulsion layer was applied at a rate of 0.8 g / m ² , and the silver halide was converted to silver nitrate at a rate of 1.0 g / m ² . The undercoat layer and the emulsion layer contain formalin as a hardening agent in an amount of 5.0 mg / g gelatin relative to gelatin. 40 ℃ after drying
After heating for 5 days, the emulsion layer
No. 14 The nucleus liquid of Example 1 (using P-2 polymer) was applied and dried to prepare a lithographic printing plate.

The silver halide emulsion was obtained by adding 4 × 10 ^-6 mol of rhodium chloride per mol of silver halide at the time of physical ripening, and had an average grain size of 0.3 μm. The lithographic printing plate prepared as described above was exposed to a fine line image with a plate making camera having an image reversing mechanism, and immersed in an automatic developing machine storing 10 liters of a developing solution and a stabilizing solution in a tank. The developing solution and the stabilizing solution used are shown below.

<Developer> Potassium hydroxide 20 g Sodium hydroxide 15 g Anhydrous sodium sulfite 45 g 2-Aminoethyl-aminoethanol 12 g 2-Mercapto-5-n-heptyloxasiasol 0.25 g Water is added to make 1 liter. pH adjusted to 13.4.

<Stabilizer> Potassium monophosphate 30 g Sodium bisulfite 2.5 g Ethylene glycol 5 g 2-Mercapto 5-n heptyl oxathiazole 0.1 g Triethanolamine 8 g Make up to 1 liter with water. pH adjusted to 6.

A lithographic printing plate prepared by performing a 100 m ² running process using the developing solution and the stabilizing solution was subjected to a printing test in the following manner.

In the printing test, the printing plate was transferred to an offset printing machine (A
M1250: Adresograph Multigraph Co., Ltd.), and after treating the plate surface with the following starter solution, AB-Dick 3-1012 black ink as an ink,
Printing was performed using OD30 (humidifying liquid manufactured by Mitsubishi Paper Mills) as a humidifying liquid.

<Starter liquid> Phosphoric acid 5 g Colloidal silica (20% aqueous solution) 10 g Dipropylene glycol 20 g Diethanolamine 10 g Compound A 10 g Hydrophobizing agent 1 g Make up to 1 liter with water. The pH was adjusted to 6. The hydrophobizing agent is 2-mercapto-5-n-heptyl-oxadiazole.

Seven types of starter solutions were prepared using the compounds shown in Table 1 as the compound A, and printing was started immediately after the starter solutions were applied to the plate surface.

The ink acceptability was evaluated as the number of prints until the ink was brought into contact with the plate surface and the paper was started to be fed until the image density became stable and a good printed product was obtained. Table 1 shows the results.

[0066]

[Table 1]

[0067]

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[0068]

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From the above results, it can be seen that the starter liquid using the compound of the present invention greatly improves ink acceptability.

Example 2 The electrolytic surface roughening treatment and the anodic oxidation of an aluminum support were carried out according to the method described in US Pat. No. 5,427,889, on a plateau having an average diameter of about 5 μm.
0.30 μm pits are about 5,600 per 100 μm ²
And the average diameter of these pits is 0.08 μm
Was obtained as an aluminum plate having a thickness of 0.30 mm. This aluminum plate was anodized after the surface roughening treatment, and had an average roughness (Ra) of 0.5 to 0.6 μm.

Curry Lee (C)
A physical development nucleus solution comprising a silver sol prepared by the arey Lea method was applied, and then dried. The amount of silver contained in the physical development nucleus layer was 3 mg / m ² .

As a silver halide emulsion, alkali-treated gelatin was used as a protective colloid, and potassium hexachloroiridate (IV) having an average particle diameter of 0.2 μm was added to the silver halide emulsion in an amount of 0.006 m per mol of silver by a control double jet method.
A mol-doped silver chloroiodobromide emulsion (AgBr 20 mol%, AgI 0.4 mol%) was prepared. Further, this emulsion was subjected to sulfur-gold sensitization, and spectral sensitization was performed using 3 mg of the sensitizing dye of Chemical Formula 15 per 1 g of silver.

[0073]

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A surfactant was added to the silver halide emulsion thus prepared, and the silver amount was 2 g / m ² (gelatin amount 2.3) on the aluminum support coated with the physical development nuclei.
g / m ² ) and dried to obtain a lithographic printing material.

A 633 nm red LD
An image was output by an output machine using a laser as a light source, and then processed by a plate-making processor (SLT-N automatic developing machine manufactured by DuPont) to prepare a lithographic printing plate. The plate-making processor includes a developing step (immersion at 21 ° C. for 15 seconds), a washing step (separating the emulsion layer with a scrub roller while spraying a washing liquid at 33 ° C. for 10 seconds), and a finishing step (21 ° C. 5 seconds shower) and a drying step. The rinsing process of the plate-making processor uses three rinsing liquids.
It consists of a tank that stores 0 liters, a unit that feeds the lithographic printing material from the tank to the lithographic printing material via a pump to remove the emulsion layer, and a unit that circulates the washing water from the tank through a filter installed outside the system. . As the filtration filter, a cylindrical 5 μm filter was used.

The following developing solution, washing solution and finishing solution were used. <Developer> Sodium hydroxide 20 g Hydroquinone 20 g 1-Phenyl-3 pyrazolidinone 2 g Sodium sulfite 80 g Monomethylethanolamine 6 g 2-Mercapto-5-n-heptyloxasiasol 0.5 g Sodium thiosulfate 6 g Sodium ethylenediaminetetraacetate 5 g Polyethylene glycol (Average molecular weight 400) 10 g Water is added to adjust the total amount to 1 liter. The pH was adjusted to 13.0.

<Washing solution> First potassium phosphate 40 g Sodium sulfite 10 g Monomethylethanolamine 6 g 2-mercapto-5-n-butyloxyoxasitol 0.5 g Water is added to adjust the total volume to 1 liter. The pH was adjusted to 6.0.

<Finishing liquid> 15 g of gum arabic 10 g of sodium phosphate monobasic 2 g of 2-mercapto-5-nheptyl-oxadiazole Water was added to adjust the total volume to 1 liter. The pH was adjusted to 6.0.

A 100 plate (Kikuzen size) running process was performed by the above method, and a lithographic printing plate having a 100 plate surface was mounted on a printing machine (Heidelberg MO: Al-color water supply device; manufactured by Heidelberg), and the plate surface was treated with the following starter solution. Processed and started printing. Printing was performed using New Champion Ink H ink manufactured by Dainippon Ink Co., Ltd. and a commercially available humidifying solution for PS plates, and ink acceptability and water retention at the start of printing were evaluated. The ink acceptability was evaluated by the number of sheets after the start of printing until the change in image density did not occur. Table 2 shows the results.

<Starter liquid> Carboxymethylcellulose 140 g Phosphoric acid 6 g Glycerin 40 g Organic solvent (alkylbenzene) 350 g Compound A 10 g Hydrophobizing agent 1 g The total volume is adjusted to 1 liter with water. PH was adjusted to 4.8. The hydrophobizing agent is 2-mercapto-5-n-heptyl-
Oxadiazole. Compound A is the same as that used in Example 1.

[0081]

[Table 2]

As is clear from the above results, the aluminum lithographic printing plate has not conventionally used a starter liquid. However, by using a starter liquid containing the compound of the present invention, ink reception at the start of printing can be performed. Dramatically improved.

[0083]

By using the starter liquid of the present invention, ink receptivity at the start of printing of a lithographic printing plate utilizing image silver as ink receptivity is improved. In particular, the ink acceptability, which has been reduced by the running treatment of the plate-making treatment liquid, can be greatly improved.

Claims (5)

[Claims] 1. A starter solution for treating a plate surface of a lithographic printing plate utilizing image silver as ink receptivity at the start of printing, comprising: an amine compound having a propyleneoxy group and an ethyleneoxy group; A starter solution containing at least one selected from a fatty acid amide compound having an oxy group and a quaternary ammonium compound having a propyleneoxy group and an ethyleneoxy group. 2. The starter liquid according to claim 1, wherein the starter liquid further contains a compound that renders image silver hydrophobic. 3. A lithographic printing plate obtained by exposing a lithographic printing material having a physical development nucleus layer between an aluminum support and a silver halide emulsion layer to the lithographic printing plate, followed by development, washing and finishing. 3. The starter solution according to claim 1, which is a plate. 4. A lithographic printing plate obtained by exposing a lithographic printing material having at least a silver halide emulsion layer and a physical development nucleus layer in this order on a support, followed by development and stabilization. The starter liquid according to claim 1 or 2, wherein 5. A printing method, comprising mounting the lithographic printing plate on a printing press, and processing and printing the plate surface of the lithographic printing plate with the starter liquid.