JP2023043677A - Dampening water concentrated composition for lithographic printing plate - Google Patents

Abstract

To provide, in lithographic printing using non-processed CTP plate 10, a dampening water concentrated composition for lithographic printing plate that can suppress the occurrence of stains on non-image area 12 of a printed matter during printing.SOLUTION: The dampening water concentrated composition for lithographic printing plate contains, as essential component, a polyoxyethylene polyoxybutylene block polymer, a polyoxyethylene sorbitan monofatty acid ester, a dialkylsulfosuccinate, and an alkylene glycol monoalkyl ether. The dampening water concentrated composition for lithographic printing plate is diluted with tap water and used as dampening water 1.SELECTED DRAWING: Figure 1

Description

The present invention relates to a concentrated dampening solution composition for planographic printing plates used in offset printing.

Conventionally, concentrated dampening solution compositions for planographic printing plates used in offset printing are known (for example, Patent Documents 1 and 2). These are patent applications filed by the assignee of the present application.

JP 2008-126573 A JP 2008-126575 A

In recent years, process-less CTP plates (CTP: a computer-to-plate system in which computer-generated data is passed through a plate setter and directly output as a printing plate (computer to plate)), which do not require alkaline developer processing and desensitizing processing solutions, have become popular. is coming. Process-less CTP plates are created by setting a plate on which an image is formed with a laser beam in a printing machine, softening the resin in the non-image areas with dampening water, and removing the resin with the viscosity of the ink. forming However, in lithographic printing using a non-processed CTP plate, when conventional dampening water is used, there is a problem that stains may occur in the non-image areas of the printed matter during printing.

The problem to be solved by the technique of the present specification has been made in view of the above-mentioned points. It is an object of the present invention to provide a concentrated dampening water composition for a lithographic printing plate capable of suppressing the

The concentrated dampening water composition for a lithographic printing plate according to the embodiment of the present specification is a concentrated dampening water composition for a lithographic printing plate used in offset printing as a dampening solution for a lithographic printing plate, and comprises ,
1) A polyoxyethylene polyoxybutylene block polymer represented by the following general formula (I) (hereinafter abbreviated as "POE/POB"),

(However, a, b, c: integers satisfying the requirements of 2 ≤ a + c ≤ 200 and 10 ≤ b ≤ 50)
2) Polyoxyethylene sorbitan mono fatty acid ester represented by the following general formula (II),

(where R ¹ is an alkyl group having 8 to 18 carbon atoms; R ² , R ³ and R ⁴ are an oxyethylene group);
3) a dialkyl sulfosuccinate represented by the following general formula (III),

(wherein R ⁵ and R ⁶ : linear or branched alkyl groups having 6 to 12 carbon atoms; M: H, Na, K, Li, NH ₄ , alkylamines, alkyldiamines, alkyltriamines, alkyltetra amines or aminoalcohols),
4) an alkylene glycol monoalkyl ether represented by the following general formula (IV),

(where R ⁷ is a linear or branched alkyl group having 1 to 4 carbon atoms, R ⁸ is a hydrogen atom, a methyl group or an ethyl group),
characterized by containing

According to the concentrated dampening water composition for a lithographic printing plate according to the embodiment of the present specification, it is possible to suppress the occurrence of stains in the non-image areas of the printed matter during printing.

Here, in the concentrated dampening solution composition for lithographic printing plates,
5) a triol represented by the following general formula (V),

(However, h: an integer that satisfies the requirements of 1 ≤ h ≤ 10)
may contain

According to this, the non-image portion of the printing plate can be suitably moistened or retained.

Further, in the concentrated dampening solution composition for a lithographic printing plate,
6) a diol represented by the following general formula (VI),

(However, i: an integer that satisfies the requirements of 1 ≤ i ≤ 20)
may contain

According to this, the non-image portion of the printing plate can be suitably moistened or retained.

According to the concentrated dampening water composition for a lithographic printing plate of the embodiment, it is possible to suppress the occurrence of contamination in the non-image area of the printed matter during printing.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a conceptual cross-sectional view of a printing plate in which the concentrated dampening water composition for a lithographic printing plate of the embodiment is used.

Hereinafter, a dampening solution concentrated composition for a lithographic printing plate according to an embodiment of the present specification will be described. In the embodiments, "%" indicating content means "% by mass" unless otherwise specified. Moreover, the scope of the present invention is not limited to the scope disclosed in the embodiments. A concentrated dampening solution composition for a lithographic printing plate according to an embodiment comprises 1) POE/POB, 2) polyoxyethylene sorbitan mono fatty acid ester, 3) dialkyl sulfosuccinate, and 4) alkylene glycol monoalkyl ether. contains In another embodiment, the dampening solution concentrate composition for lithographic printing plates can contain 5) a triol. As yet another embodiment, 6) can contain a diol. Each of these components 1) to 6) are general-purpose ones, and commercially available products can be used.

1) POE/POB is represented by the following general formula (I).

In the above general formula (I), a, b, and c are integers satisfying the requirements of 2≤a+c≤200 and 10≤b≤50. As another embodiment, a, b, c can be integers satisfying the requirements of 5≤a+c≤40, 20≤b≤40.

POE/POB having an average molecular weight (weight average molecular weight, hereinafter the same) of 1000 to 5000 is used. In another embodiment, the average molecular weight of POE/POB can be 1500-4000, and in yet another embodiment 2000-4000.

POE/POB, as shown in FIG. 12 to moisturize or retain water.

2) Polyoxyethylene sorbitan mono fatty acid ester is represented by the following general formula (II).

In general formula (II) above, R1 is an alkyl group having 8 to 18 carbon atoms. In another embodiment, R ¹ can be an alkyl group of 10-14 carbon atoms. R ² , R ³ and R ⁴ are oxyethylene groups. Further, in the above general formula (II), d, e, and f are integers satisfying the requirement of 1≤d+e+f≤6. As another embodiment, d, e, f can be integers satisfying the requirement 1≤d+e+f≤4.

The polyoxyethylene sorbitan monofatty acid ester lowers the surface tension of the dampening solution 1 for lithographic printing plates and suppresses bleeding (bleeding) of the ink 13 into the dampening solution 1 for lithographic printing plates.

3) Dialkyl sulfosuccinate is represented by the following general formula (III).

In general formula (III) above, R ⁵ and R ⁶ are straight or branched alkyl groups having 6 to 12 carbon atoms. In another embodiment, R ⁵ and R ⁶ can be linear or branched alkyl groups of 6-10 carbon atoms. M is H, Na, K, Li, _NH4 , alkylamines, alkyldiamines, alkyltriamines, alkyltetraamines or aminoalcohols. In another embodiment, M can be Na, K, aminoalcohols.

The dialkyl sulfosuccinate adheres to the non-image portion 12 of the printing plate and makes the non-image portion 12 of the printing plate hydrophilic.

4) Alkylene glycol monoalkyl ether is represented by the following general formula (IV).

In the general formula (IV) above, R ⁷ is a linear or branched alkyl group having 1 to 4 carbon atoms. In another embodiment, R ⁷ can be a linear or branched alkyl group of 3-4 carbon atoms. ^R8 is a hydrogen atom, a methyl group or an ethyl group. As another embodiment, R ⁸ can be a hydrogen atom or a methyl group. In the above general formula (IV), g is 1-2.

Alkylene glycol monoalkyl ether can improve the efficiency of water supply to the printing plate.

5) The triol is represented by the following general formula (V).

In the above general formula (V), h is an integer that satisfies the requirement of 1≤h≤10. As another embodiment, h can be an integer satisfying the requirement 1≤h≤8.

The triol serves to keep the non-image portion 12 of the printing plate moist or retain water.

6) The diol is represented by the following general formula (VI).

In the above general formula (VI), i is an integer that satisfies the requirement of 1≤i≤20. As another embodiment, i can be an integer satisfying the requirement 1≤i≤15.

The diol is for moisturizing or retaining water in the non-image portion 12 of the printing plate.

The concentrated dampening water composition for a lithographic printing plate of the embodiment contains the above 1) to 4) as essential components, and when diluted with water and used as the dampening water 1 for the untreated CTP plate 10, The resin of the non-image area 12 of the non-processed CTP plate 10 is easily removed on the printing machine, and the surface of the formed non-image area 12 is kept moist with dampening water 1 to suppress the occurrence of stains. can do. In addition, it is possible to suppress the occurrence of printing stains that occur when printing is started after the printing press is temporarily stopped (when printing is restarted). Further, the dampening water 1 forms a water-retaining film (oil-desensitizing film) on the non-image area 12 to increase the hydrophilicity of the non-image area 12, thereby clearly distinguishing the lipophilicity of the image area 11 from the lipophilicity of the image area. It is possible to improve the riding property of the ink 13 of 11.

That is, since the dampening solution 1 obtained by diluting the concentrated dampening solution composition for a lithographic printing plate of the embodiment has excellent wettability and permeability, it can be used in a printing machine with a continuous water supply type dampening solution supply device without processing a CTP plate. 10, the action of the dampening water 1 softens the resin in the non-image area 12, and the viscosity of the ink 13 makes it easier to remove the resin. can. The dampening water 1 acts to form a stable water-retaining film on the non-image area 12 of the printing plate, and a uniform water film of the dampening water 1 can be maintained. Due to this action, it is possible to prevent contamination during printing and entanglement of halftone dots with the ink 13, so that it is possible to obtain high-quality printed matter. In addition, when the printing press is stopped, the water-retaining film formed on the non-image area 12 of the printing plate suppresses the drying of the printing plate surface, which eliminates smudges at the time of printing after the printing press is temporarily stopped (improved start-up when printing is restarted). ) is faster and can reduce wasted paper. Further, since the image portion 11 of the unprocessed CTP plate 10 is not affected, plate skipping (plate removal) can be suppressed.

The concentration of each component in the concentrated dampening solution composition for a lithographic printing plate in the embodiment is
1) POE/POB 0.1-10%, in another embodiment 0.2-8%, in a further embodiment 1-4%
2) Polyoxyethylene sorbitan mono fatty acid ester: 0.1-5%, in another embodiment 0.2-3%, in yet another embodiment 0.2-2%
3) Dialkyl sulfosuccinate 0.1-5%, in another embodiment 0.2-3%, in yet another embodiment 0.2-2%
4) Alkylene Glycol Monoalkyl Ether 5-70%, in another embodiment 5-60%, in a further embodiment 10-50%
5) Triol--0-15%, in another embodiment 2-15%, in a further embodiment 5-12%
6) Diol... 0-20%, in another embodiment 5-15%, in a further embodiment 8-15%
can be

The balance of each component in the concentrated dampening solution composition for lithographic printing plates of the embodiment is such that POE/POB is 1 to 20 parts by mass (1 to 20 parts by mass as another embodiment) with respect to 100 parts by mass of alkylene glycol monoalkyl ether. 10 parts by mass), 0.05 to 10 parts by mass of polyoxyethylene sorbitan monofatty acid ester (0.05 to 5 parts by mass as another embodiment), 0.05 to 10 parts by mass of dialkyl sulfosuccinate (another 0.05 to 5 parts by weight as an embodiment), 0 to 50 parts by weight of triol (10 to 40 parts by weight as another embodiment), 0 to 50 parts by weight of diol (10 to 50 parts by weight as another embodiment part), can be

In the concentrated dampening water composition for a lithographic printing plate of the embodiment, in addition to a functional agent that increases the hydrophilicity of the non-image area 12, from the viewpoint of optimizing the liquid film characteristics of the dampening water 1 on the plate surface, A surfactant, a solvent having surface activity, a water-soluble polymer compound, a pH adjuster, a wetting agent, an antiseptic, an antifoaming agent, and the like can be added as appropriate.

Surfactants and solvents having surface activity can be used as aids for improving wettability. Anionic surfactants and nonionic surfactants can be used as surfactants.

Examples of anionic surfactants include fatty acid salts, abietates, hydroxyalkanesulfonates, alkanesulfonates, alkylnaphthalenesulfonates, alkylphenoxypolyoxyethylenepropylsulfonates, polyoxyethylene alkylsulfenyl ether salts, N-methyl-N-oleyltaurate sodium salts, N-alkylsulfosuccinic acid monoamide disodium salts, petroleum sulfonates, sulfated castor oil, sulfated beef tallow, fatty acid alkyl ester sulfates, alkyl sulfates, poly Oxyethylene alkyl ether sulfates, fatty acid monoglyceride sulfates, polyoxyethylene alkylphenyl ether sulfates, polyoxyethylene styrylphenyl ether sulfates, alkyl phosphates, polyoxyethylene alkyl ether phosphates, polyoxy Ethylene alkylphenyl ether phosphate ester salts, partially saponified styrene-maleic anhydride copolymers, naphthalenesulfonate formalin condensates, and the like can be used.

As nonionic surfactants, acetylene diol dipolyoxyethylene ethers, polyoxyethylene polystyrylphenyl ethers, polyoxyethylene polyoxypropylene alkyl ethers, glycerin fatty acid partial esters, sorbitan fatty acid partial esters, pentaerythritol fatty acid Partial esters, propylene glycol mono fatty acid esters, sucrose fatty acid partial esters, polyoxyethylene sorbitol fatty acid partial esters, polyethylene glycol fatty acid esters, polyglycerin fatty acid partial esters, polyoxyethylene hydrogenated castor oil, polyoxyethylene glycerin Fatty acid partial esters, fatty acid diethanolamides, N,N-bis-2-hydroxyalkylamines, polyoxyethylene alkylamines, triethanolamine fatty acid esters, polyoxyethylene polyoxypropylene block polymers, polyoxyethylene Polyoxypropylene random polymers, trialkylamine oxides, fluorosurfactants, silicone surfactants and the like can be used. Alternatively, acetylenediol dipolyoxyethylene ethers, polyoxyethylene polyoxypropylene block polymers can be used.

Alkylpyrrolidones, acetylenediols, and the like can be used as the surface-active solvent.

In embodiments, the added amount of these surfactants and surfactants can be 0-5%. As another embodiment, it can be 0.1-3%.

The water-soluble polymer compound can be used as an auxiliary agent for imparting viscosity to the concentrated fountain solution composition for lithographic printing plates.

Examples of water-soluble polymer compounds include gum arabic, starch derivatives (dextrin, enzyme-degraded dextrin, carboxymethylated starch, phosphate starch, octenyl succinated starch, etc.), alginate, cellulose derivatives (hydroxypropyl methylcellulose, carboxymethyl cellulose, carboxy ethyl cellulose, methyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose and derivatives thereof), polyacrylic acid and its copolymers, alkylene/maleic anhydride copolymers, polyvinylpyrrolidone and the like.

In embodiments, the amount of water-soluble polymer added can be 0-5%. In another embodiment, it can be 0.01-3%.

The pH adjusting agent has pH adjusting and pH buffering effects on the concentrated dampening water composition for lithographic printing plates, and is effective in desensitizing the non-image portion 12 and in appropriately etching or preventing corrosion. A water-soluble organic acid or inorganic acid or a salt thereof can be used as the pH adjuster. Organic acids include citric acid, ascorbic acid, dl-malic acid, dl-tartaric acid, dl-lactic acid, acetic acid, Glycolic acid, gluconic acid, malonic acid, adipic acid, succinic acid, levulinic acid, sulfanilic acid, phytic acid, organic phosphonic acid, polycarboxylic acid and the like can be used. Examples of inorganic acids that can be used include phosphoric acid, metaphosphoric acid, pyrophosphoric acid, hexametaphosphoric acid, polyphosphoric acid, boric acid, nitric acid, and sulfuric acid. Furthermore, alkali metal salts, alkaline earth metal salts, ammonium salts, and organic amine salts of these organic or inorganic acids can also be used as appropriate. These organic acids, inorganic acids, or salts thereof can be used alone. , or two or more thereof may be used in combination.

The pH adjuster can be used so that the dampening water 1 obtained by diluting the concentrated dampening water composition for a lithographic printing plate has a pH in the acidic range of 3-6. In embodiments, the amount of the pH adjuster added can be 0 to 10%, and in another embodiment, 0.1 to 5%, relative to the concentrated fountain solution composition for lithographic printing plates.

A humectant can be used as an auxiliary agent for imparting moisturizing properties or water retention to the concentrated dampening solution composition for lithographic printing plates. Some wetting agents overlap with the aforementioned diols and triols, and in such cases, the aforementioned diols and triols can be used together by increasing the amount of the aforementioned diols and triols.

Wetting agents include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butylene glycol, hexylene glycol, 2-ethyl-1,3-hexanediol, trimethylolpropane, glycerin, polyethylene glycol, polypropylene glycol and glycerin, polyglycerin. , pentaerythritol and the like can be used.

In embodiments, the amount of humectant added can be 0 to 10%, and in another embodiment, 0.5 to 5%, relative to the concentrated fountain solution composition for lithographic printing plates.

Preservatives include bromonitroalcohol-based 2-bromo-2-nitropropane-1,3-diol, 1,1-dibromo-1-nitro-2-ethanol, 3-bromo-3-nitropentane-2,4 - diols, as well as imidazole derivatives, sodium dehydroacetate, sodium salicylate, sodium benzoate, 4-isothiazolin-3-one derivatives, benztriazole derivatives, derivatives of amidine or guanidine, derivatives of pyridine, quinoline or guanidine, derivatives of diazine or triazole Derivatives, derivatives of oxazole or oxazine, and the like can be used.

In the embodiment, the amount of the preservative to be added is an amount that exhibits a stable effect against the bacteria, mold, yeast, etc. of the dampening water 1 when diluted and used, and varies depending on the type of bacteria, mold, yeast, etc. It can range from 0 to 5.0%. In another embodiment, it can be 0.05-3.0%. Also, two or more preservatives effective against various molds, bacteria and yeasts can be used in combination.

Suitable antifoaming agents are silicone antifoaming agents, of which self-emulsifying, emulsifying and dispersing, solubilizing and the like can be suitably used. In embodiments, the amount added can be 0-0.2%. In another embodiment, it can be 0.01-0.1%.

The balance is water as a component of the concentrated dampening solution composition for lithographic printing plates of the embodiment. Therefore, it is ideal to use demineralized water or ion-exchanged water, but generally soft water (hardness: less than 60 mg/L) can be used without any problem. A concentrated fountain solution composition for a lithographic printing plate can be obtained as an aqueous solution in which the various components described above are dissolved.

When the concentrated dampening solution composition for lithographic printing plates of the embodiment is used, it is usually diluted with tap water, well water, or the like by a factor of 10 to 100 to obtain dampening solution 1 (composition) for use.

The present invention will be described in more detail below with reference to examples. Table 1 shows the formulations of the dampening solution concentrated compositions for lithographic printing plates of Examples. The unit is gram, and water was added to the concentrated dampening solution compositions for lithographic printing plates of Examples to make a final volume of 1000 mL. Each concentrated dampening solution composition for lithographic printing plates was diluted to dampening solution 1 at the time of use.

The performance evaluation of the dampening solution concentrate composition for lithographic printing plates was evaluated by carrying out lithographic printing. In lithographic printing, a concentrated dampening water composition for lithographic printing was diluted 50-fold with tap water and subjected to a printing test as dampening water 1 to be actually used. For the printing machine, the name "DAIYA 1F-4" manufactured by Mitsubishi Heavy Industries, Ltd. was used, the oil-based ink 13 was named "TK NEX NV" manufactured by Toyo Ink Co., Ltd., and the high-sensitivity UV ink 13 was manufactured by Toyo Ink Co., Ltd. The unprocessed CTP plate 10 used was the name "SONORA CX" manufactured by Kodak LLC under standard conditions. The set temperature of the dampening water 1 was set at 10°C. 10,000 sheets were printed at a printing speed of 10,000 sheets/hour. entanglement, rising property (stain recovery property) when restarting printing, and presence or absence of excessive emulsification of ink 13 were checked and evaluated. Evaluation methods are described below.

Startup performance at the start of printing (stain recovery performance)
As for the start-up property at the start of printing, the finished printed matter was checked at the start of printing, and the elimination of stains was evaluated. Then, it was evaluated as ○ when the stain was resolved within 10 sheets of printing, △ when the stain was resolved within 50 sheets of printing, and × when the stain was not resolved even after 50 sheets of printing were started. bottom.

Entanglement of Ink 13 in Halftone Dot Image Area 11 Entanglement of ink 13 in halftone image area 11 was evaluated by checking the printed matter and evaluating the entanglement of ink 13 in halftone image area 11 . In the halftone dot image portion 11 of the printed matter, ◯ indicates that no entanglement of the ink 13 was observed; It was evaluated as x.

Contamination of Non-Image Area 12 Contamination of the non-image area 12 was evaluated by checking the printed matter and evaluating the occurrence of contamination of the non-image area 12 . In the non-image area 12 of the printed matter, the evaluation was made as ◯ when no stain was observed, Δ when light stain was observed, and X when excessive stain was observed.

Entanglement of Ink 13 on Mizumoto Roller Entanglement of ink 13 on the Mizumoto roller was evaluated by observing the state of the Mizumoto roller after printing 10,000 sheets. Then, the Mizumoto roller was evaluated as ○ when no entanglement of the ink 13 was observed, Δ when light entanglement of the ink 13 was observed, and x when excessive entanglement of the ink 13 was observed. bottom.

Startup performance when restarting printing (stain recovery performance)
After printing 10,000 sheets, the printing press was stopped for 30 minutes, and then the printed matter was checked for stains when restarting printing, and the removal of the stains was evaluated. ○ indicates that the stain was removed within 10 sheets after restarting printing; Those that did not were evaluated as x.

Presence or absence of excessive emulsification of the ink 13 To determine whether or not the ink 13 is excessively emulsified, observe the state of the ink 13 on the ink roller of the printing machine after printing 10,000 sheets, and check the emulsification state of the ink 13 under the influence of the dampening water 1. evaluated. The ink 13 was evaluated as ◯ when it was in an appropriate state, Δ when light emulsification was observed, and X when excessive emulsification was observed.

Table 2 shows the results of evaluation with oil-based ink 13, and Table 3 shows the results of evaluation with high-sensitivity UV ink 13, for the concentrated dampening solution compositions for lithographic printing plates of Examples.

In addition, the concentrated dampening solution composition for lithographic printing plates of the embodiment was also evaluated for removal of the unprocessed CTP plate 10 (removal of the image area 11). To evaluate plate removal, "SONORA CX" plate-made under standard conditions was immersed in dampening water 1 (adjusted to 40°C) diluted 25 times and 50 times with clean water for 4 hours, and the state was evaluated. . Then, the case where there was no influence on the image portion 11 was evaluated as ◯, the case where the plate removal of the image portion 11 could be confirmed although it was slight, and the case where the plate removal of the image portion 11 could be confirmed was evaluated as ×. . The evaluation results are shown in Table 4.

The concentrated dampening solution composition for lithographic printing of the embodiment was excellent in all test items, yielding good prints, did not cause plate removal, and was excellent as dampening solution 1. Admitted.

Reference Signs List 1... dampening water, 10... CTP plate, 11... image area, 12... non-image area, 13... ink.

Claims (3)

A concentrated dampening solution composition for lithographic printing plates used in offset printing, comprising:
1) A polyoxyethylene polyoxybutylene block polymer represented by the following general formula (I) (hereinafter abbreviated as "POE/POB"),

(However, a, b, c: integers satisfying the requirements of 2 ≤ a + c ≤ 200 and 10 ≤ b ≤ 50)
2) Polyoxyethylene sorbitan mono fatty acid ester represented by the following general formula (II),

(where R ¹ is an alkyl group having 8 to 18 carbon atoms; R ² , R ³ and R ⁴ are an oxyethylene group);
3) a dialkyl sulfosuccinate represented by the following general formula (III),

(R ⁵ and R ⁶ : linear or branched alkyl groups having 6 to 12 carbon atoms; M: H, Na, K, Li, NH ₄ , alkylamines, alkyldiamines, alkyltriamines, alkyltetra amines or aminoalcohols),
4) an alkylene glycol monoalkyl ether represented by the following general formula (IV),

(provided that R ⁷ : straight or branched alkyl group having 1 to 4 carbon atoms, R ⁸ : hydrogen atom, methyl group or ethyl group),
A concentrated fountain solution composition for a lithographic printing plate, comprising: 5) a triol represented by the following general formula (V),

(However, h: an integer that satisfies the requirements of 1 ≤ h ≤ 10)
The dampening solution concentrate composition for a lithographic printing plate according to claim 1, comprising: 6) a diol represented by the following general formula (VI),

(However, i: an integer that satisfies the requirements of 1 ≤ i ≤ 20)
The dampening solution concentrate composition for a lithographic printing plate according to claim 1, comprising:

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