JP3361613B2 - Rinse water for lithographic printing plates and plate making method for lithographic printing plates - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to washing water used in plate making of a lithographic printing plate and a plate making method of a photosensitive lithographic printing plate using the same. The present invention relates to rinsing water with improved ink adhesion at the time of printing and a method for making a photosensitive lithographic printing plate using the same. 2. Description of the Related Art Conventionally, a photosensitive lithographic printing plate is generally processed through processing steps such as a developing step, a washing step, and a step of providing a hydrophilic plate surface protective layer. Generally, in order to prevent the developer and the photosensitive layer components eluted therefrom from remaining on the developed printing plate, a water washing treatment is performed after the development. In an automatic developing device, it is common practice to circulate and repeatedly use washing water for the purpose of saving water, etc., but in the case of a lithographic printing plate washed with repeatedly used washing water, the printing ink is printed on the image area. There is a case where so-called poor inking occurs, which makes it difficult to adhere. As a countermeasure for this poor inlay,
There is also a method of washing with fresh water for each lithographic printing plate, but if a large amount of washing water is used, it was effective as a countermeasure for inking, but the amount of wastewater increased undesirably, In addition, washing with a small amount of fresh water did not provide a complete measure against poor inking. [0003] Accordingly, an object of the present invention is to provide a photosensitive lithographic printing plate which can be used repeatedly in the washing step after the development processing, or when a small amount of fresh water is used. However, it is an object of the present invention to provide a washing water which does not cause an ink deposition failure at the start and a method of making a lithographic printing plate using the same. Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above object, and as a result, have found washing water that can effectively prevent poor inking, and constitute the present invention. The object of the present invention can be achieved by the configuration described in (1) below. (1) Image-sensitizing a photosensitive lithographic printing plate and developing
A step of washing with water after the step of developing;
Providing an aqueous plate surface protective layer on a printing plate
In the printing plate making method, the washing water in the washing step is used.
Is a compound represented by the following general formula [I] or [II]
For making a photosensitive lithographic printing plate characterized by containing
Law. [0005] Hereinafter, the present invention will be described in detail. General formulas [I] and [II] contained in the washing water of the lithographic printing plate of the present invention.
The compound of the formula (a) or the compound of the compound group (a) is effective for improving the ink adhesion at the start. Although the mechanism is not clear, it is considered that it has an action of preventing adsorption to the image portion of the developer hydrophilic component in the washing water. Representative examples of the general formulas [I] and [II] used in the present invention are shown below, but the present invention is not limited thereto. (Exemplary compound) [0009] [0010] Among these compounds, [I] -2 and [I]
-3, [I] -4, [II] -2, [II] -3 and [I
I] -4 is preferable because it is easily dissolved in water. In the present invention, the compounds represented by the following general formula [I] or [II] contained in the rinsing water of the lithographic printing plate can be used alone or in combination of two or more. The amount of these compounds added to the washing water is 0.001 to 5% by weight based on the washing water.
, More preferably 0.001 to 1% by weight, particularly preferably 0.001 to 0.5% by weight. When the amount is less than 0.001% by weight, the effect of improving the inking property, which is the object of the present invention, is small. The addition is disadvantageous in running cost, and adversely affects the physical properties of the washing water. The washing water of the present invention has the general formula [I], [I
It is preferable to contain a chelating agent in addition to the compound of I). The chelating agent is effective for increasing the stability of the compounds [I] and [II] in the washing water. Examples of the chelating agent used in the present invention include EDTA (ethylenediaminetetraacetic acid) and its salts, NTA (nitrilotriacetic acid) and its salts, HEDTA (hydroxyethylethylenediaminetriacetic acid) and its salts, DPTA (diethylenetriaminepentaacetic acid) and Its salts, TTHA (triethylenetetramine hexaacetic acid) and its salts, HIDA (hydroxyethyliminodiacetic acid) and its salts, DHEG (dihydroxyethylglycine) and its salts, CyDTA (cyclohexanediaminetetraacetic acid) and its salts, EHPG [ Ethylenebis (hydroxyphenylglycine)] and salts thereof, H
EDP (1-hydroxyethylidene-1,1-diphosphonic acid) and its salts, ATMP [aminotri (methylene phosphonic acid)] and its salts, polymer electrolytes such as sodium polyacrylate, sodium polymethacrylate, sodium polymaleate, Examples thereof include sodium polyitaconate and a copolymer thereof, but are not limited to these as long as they exhibit chelating power to metal ions. The chelating agent in the present invention comprises 1
Species or a combination of two or more can be used. The preferred amount of the chelating agent is 0.0001 to the washing water.
To 0.01% by weight, more preferably 0.001 to
0.005% by weight, particularly preferably 0.002 to 0.0
03% by weight. The amount of chelating agent used is 0.0001
When the content is in the range of 0.01 to 0.01% by weight, the compounds [I] and [I
The concentration is suitable for chelating a metal ion that reduces the stability of I). If the content is less than 0.0001% by weight, metal ions that cannot be chelated remain and 0.01%
If the amount exceeds 10% by weight, residual metal ions become small, and if it is added more than that, the running cost becomes disadvantageous. The additives of the present invention (formulas [I] and [I]
The compound (I), compound group (a)) may be added to the washing water as a powder or tablet, but may be added to the washing water with a solution previously dissolved in water or a suitable organic solvent. Considering the ease of mixing with washing water, the solution type is preferred. The solution type compound in this case preferably contains the compound of the general formulas [I] and [II] or the compound of the compound group (a) in an amount of 1% by weight or more, more preferably 5% by weight or more.
In the washing water of the present invention, the compounds of the general formulas [I] and [II] and the compounds of the compound group (a) can be used in combination. The washing water to which the additive of the present invention is added can be used as a positive or negative photosensitive lithographic printing plate (hereinafter abbreviated as PS plate).
Can be used in the water washing step during plate making. Positive PS plates to which the present invention can be applied are described in, for example, JP-B-43-28403.
No., JP-A-62-14652, 63-226641
And a PS plate as described in detail in JP-A-2-8663. Negative PS plates include, for example, those using a diazo compound as a photosensitive material, those using a photocrosslinkable compound, and those using a photopolymerizable compound. As the diazo compound, conventionally known ones can be appropriately used. Examples thereof include diazo resin inorganic salts, which are organic solvent-soluble reaction products of a condensate of p-diazodiphenylamine and formaldehyde or acetaldehyde with hexafluorophosphate and tetrafluoroborate, and US As described in Japanese Patent No. 3,300,309, the condensate and a sulfonic acid such as paratoluenesulfonic acid or a salt thereof, a phosphinic acid such as benzenephosphinic acid or a salt thereof, and JP-B-49-48001. Gazette, JP-A-2-2965
A co-condensed diazo resin with an aromatic compound described in Japanese Patent Publication No. 0 is also preferably used. Examples of the photocrosslinkable compound include those having a maleimide group in a side chain described in JP-A-2-236552, and examples of the photopolymerizable composition include those described in JP-A-63-257747. Items. The PS plate is exposed through a transparent original drawing by a light source rich in actinic rays such as a carbon arc lamp, a mercury lamp, a metal halide lamp, and a tungsten lamp, and then developed in a developing process by a wet process. In the plate making method of the present invention, a developer as described in JP-A-5-2271 or Japanese Patent Application No. 5-71589 is preferably used. As a method for developing the PS plate that has been image-exposed with the above-described developer, various conventionally known methods can be used. Specifically, a method of immersing an image-exposed PS plate in a developer, a method of spraying a developer from a number of nozzles on a photosensitive layer of the PS plate, and a method of spraying a PS plate with a sponge wetted with a developer Examples of the method include a method of wiping the photosensitive layer and a method of applying a developing solution to the surface of the photosensitive layer of the PS plate with a roller. After the developer is applied to the photosensitive layer of the PS plate in this manner, the surface of the photosensitive layer can be lightly rubbed with a brush or the like. The lithographic printing plate obtained by performing the above-described development processing is washed with water in a subsequent washing step, but it is necessary that the lithographic printing plate is squeezed so that the amount of the developing solution on the plate surface is reduced prior to washing. Is desirable. As a squeezing method, for example, a method of scraping the developer on the plate surface with an air knife, a method of scraping the developer on the plate surface by sliding an elastic plastic material having a smooth surface against the plate surface, or a method such as rubber. There is a method of removing the developer on the plate surface by nip pressure through a plate between an elastic roller pair having an elastic member coated on the roller surface, and a method using an elastic roller pair when an automatic developing machine is used. preferable. The rinsing water in the subsequent lithographic printing plate rinsing treatment step may be repeatedly circulated or used, or fresh water may be used for each lithographic printing plate. May be used while supplementing with fresh water as needed. The method of adding the additive of the present invention to the washing water when the washing water is repeatedly circulated is described in, for example, Japanese Patent Application Laid-Open No. 2-2569. Is filled with a predetermined amount, and an additive of the present invention measured by an appropriate method is added thereto, or a predetermined amount of washing water is mixed with an additive of the present invention measured in an appropriate method in advance, and then, a washing tank And the like. When the washing water is repeatedly used as described above, in order to reduce the mixing of the developer component in the washing water used for circulation to the desensitizing (gumming) processing solution used in the process after the washing. In some cases, fresh water may be replenished to the washing section tank. In such a case, it is needless to say that the additive of the present invention is added to fresh water, but as an adding method, a fresh water storage tank is filled with a predetermined amount of fresh water and measured by an appropriate method. A method of adding an agent, or a method of mixing a predetermined amount of washing water in advance with the additive of the present invention measured by an appropriate method, and then charging the mixture into a storage tank. Alternatively, if the storage tank is of a type that automatically keeps the water level constant by floater management, a method of adding a constant amount of the present additive to the storage tank at regular intervals is also effective. When the washing water to be used is fresh water for each plate of the lithographic printing plate, the method of adding the additive of the present invention to the washing water is described, for example, in JP-A-2-3065 or JP-A-2-3065. A method of filling a predetermined amount of fresh water into a washing water storage tank of an automatic processor as described in Japanese Patent Application No. 5-73672, and adding thereto a measured amount of the additive of the present invention, or There is a method in which a predetermined amount of washing water is mixed in advance with the additive of the present invention measured by an appropriate method, and then the mixture is charged into a storage tank. Alternatively, if the storage tank is of a type that automatically keeps the water level constant by floater management, a method of adding a constant amount of the present additive to the storage tank at regular intervals is also effective. As a method of washing the lithographic printing plate with washing water to which these additives of the present invention have been added, for example, a method of immersing the lithographic printing plate in a tank filled with washing water, preferably stirring and removing the plate,
There is a method in which washing water is supplied onto a lithographic printing plate through a pipe having a single or a plurality of narrow holes or the like. When an automatic developing machine is used, the latter method is advantageous. In this case, it is preferable that an appropriate amount of washing water is supplied at a proper timing in accordance with the passage of the PS plate through the washing section. The preferred washing water amount is 5 to 300 cc / m ² , more preferably 10 to 100 cc / m ² , and particularly preferably 20 to 80 cc / m ^2.
It is. If it is less than 5 cc / m ² , the lithographic printing plate will not be sufficiently washed with water, and if it exceeds 300 cc / m ² , the amount of wastewater will be undesirably large. The washed lithographic printing plate is preferably squeezed so as to reduce the amount of washing water remaining on the plate surface. As the squeezing method, the method of squeezing the developing solution described above is possible, but an automatic developing machine is used. In this case, a method using an elastic roller pair is preferable. In the lithographic printing plate making process, it is possible to provide various processing steps as necessary after the water washing step. The step following the water washing step mainly includes a desensitization (gumming) treatment. Examples of the desensitizing solution applicable to the present invention include, for example, JP-A No. 2-11
There is a desensitizing solution as described in detail in Japanese Patent Publication No. 3997 and Japanese Patent Publication No. 5-19920. Further, as another step following the water washing step, treatment with an aqueous solution containing a surfactant may also be mentioned. Examples of the aqueous solution containing a surfactant applicable to the present invention include, for example, JP-A-63-16
9645, 63-169646, 63-16964
7, there is an aqueous solution containing a surfactant as described in detail in each of the specifications of JP-A 63-172270. In addition, development ink filling, a process such as correction of the image area is performed, but the additive of the present invention is independent of the type of the process after washing with water,
It is possible to use. The washing water to which the additive of the present invention has been added is used not only for washing after the development of the lithographic printing plate, but also for example as washing water for an automatic washing machine after erasing, and a toner image formed by electrostatography. It is also suitably used as washing water after the elution step of a material for forming an image by eluting the lower organic resin layer on the mask. Further, it is also used as a washing transfer water after development of a photosensitive material using silver halide diffusion transfer method or silver polymerization initiation. The present invention will be described in detail with reference to the following examples. Example 1 An aqueous solution of potassium silicate having a ratio of [SiO ₂ ] / [M ₂ O] of 1.2 and SiO _{2 of} 1.5% by weight was prepared.
22 liters of a developing solution containing 0.04% by weight of N, N-dihydroxyethylbetaine amphoteric surfactant was adjusted, and PS processor PS900NP manufactured by Fuji Photo Film Co., Ltd. was used.
(A type of automatic processor where washing water is repeatedly used)
And kept at 30 ° C. In addition, tap water 7
In a liter, 7 g of compound [I] -4 and 4N of EDTA were added.
0.14 g of salt a was added, and an aqueous solution that was well stirred was charged. The post-processing tank has a PS manufactured by Fuji Photo Film Co., Ltd.
-7 liters of a desensitizing liquid consisting of 50 parts by weight of plate finishing gum FP-2W and 50 parts by weight of tap water was charged. Next, an aluminum plate having a thickness of 0.3 mm was grained with a nylon brush and a 400-mesh water suspension of pamistone, and then washed thoroughly with water. 1
After etching by dipping in 0% sodium hydroxide at 70 ° C. for 60 seconds, the substrate was washed with running water, neutralized with 20% HNO ₃ , and washed with water. This was subjected to electrolytic surface roughening treatment in a 1% nitric acid aqueous solution at an anode-time electricity quantity of 160 coulomb / dm ² using a sinusoidal alternating waveform current under the condition of V _A = 12.7 V. When the surface roughness was measured, it was 0.6 μ (Ra display). Subsequently, after immersing in a 30% H ₂ SO ₄ aqueous solution and desmutting at 55 ° C. for 2 minutes, 20% H ₂ SO _{4 was} added.
In an SO ₄ aqueous solution, a cathode was placed on the grained surface, and anodized so that the thickness became 2.7 g / m ² at a current density of 2 A / dm ² , thereby producing a substrate. The sol-gel reaction solution described below was coated on the back surface of the substrate treated as described above with a bar coater, dried at 100 ° C. for 1 minute, and dried to form a back coat layer having a coating amount of 50 mg / m ^2. The provided substrate was produced. Sol-gel reaction liquid Tetraethyl silicate 50 parts by weight Water 21.6 parts by weight Methanol 10.8 parts by weight Nitric acid 0.05 parts by weight When the above components were mixed and stirred, heat was generated in about 5 minutes. After reacting for 10 minutes, 700 parts by weight of methanol was added to prepare a back coat coating solution. Subsequently, the following photosensitive solution was applied to the surface of the substrate, and a photosensitive layer was provided so that the applied weight after drying was 2.5 g / m ² . Photosensitive solution Esterified product of 1,2-diazonaphthoquinone-5-sulfonyl chloride and pyrogallol-acetone resin (described in Example 1 of U.S. Pat. No. 3,635,709) 45 parts by weight Cresol formaldehyde novolak resin 110 parts by weight Part 2- (p-methoxyphenyl) -4,6-bis (trichloromethyl) -s-triazine 2 parts by weight Oil Blue # 603 (manufactured by Orient Chemical Industry Co., Ltd.) 1 part by weight Megafac F-177 (Dainippon) 0.4 parts by weight Methyl ethyl ketone 1000 parts by weight Propylene glycol monomethyl ether 1000 parts by weight A mat layer is formed on the surface of the photosensitive layer thus prepared as follows. A PS plate provided with a mat layer was obtained by spraying a forming resin liquid. . A 12% aqueous solution in which a part of a copolymer of methyl methacrylate / ethyl acrylate / acrylic acid (weight ratio 65:20:15) was prepared as a resin solution for forming a mat layer was prepared, and a rotary atomizing electrostatic coating machine was used. The number of rotations of the atomizing head is 25,000 rpm, the amount of the resin solution fed is 40 ml / min, the voltage applied to the atomizing head is -90 kV, the ambient temperature at the time of coating is 25 ° C, and the relative humidity is 50%. Steam is sprayed on the coated surface in 2.5 seconds to moisten, and 3 seconds after moistening, hot air having a temperature of 60 ° C and a humidity of 10% is blown for 5 seconds.
Sprayed for 2 seconds to dry. Mat height is about 6μ on average
m, the average size was 30 μm, and the applied amount was 150 mg / m ² . The PS plate obtained in this way is 1,003 mm ×
A large number of sheets cut to a size of 800 mm were prepared, and these were exposed through a document film for 60 seconds from a distance of 1 m using a 3 kW metal halide lamp. The exposed PS plate was treated with the PS processor at a rate of 24 m ² per day for a total of 3 days, and the finally treated plate was used as a sample for printing. Reference Example 1 In the washing section in Example 1, 7 g of 1- (3-chloroallyl) -3,5,7-triaza-1-azoniaadamantanchloride was used instead of 7 g of the compound [I] -4. Except for the addition, the same processing as in Example 1 was performed, and the final plate was used as a printing sample. Example 2 In Example 1, 1- (3-chloroallyl) -3,5,
7-Triaza-1-azonia adamantane chloride
Except for adding g, the same processing as in Example 1 was performed, and the final plate was used as a printing sample. Example 3 A printing plate was prepared in the same manner as in Example 1, except that compound [II] -4 was added in an amount of 14 g instead of 7 g of compound [I] -4. And Embodiment 4 In Embodiment 2 , a PS processor PS-900NP is used.
Was changed to Fuji Photo Film Co., Ltd. PS-900V (an automatic developing machine in which washing water is fresh water for each plate), and the same process as in Example 2 was performed to print the last plate. Sample. Reference Example 2 In Reference Example 1 , 1- (3-chloroallyl) -3,
Instead of 7 g of 5,7-triaza-1-azoniaadamantanchloride, 7 g of 1,3,5-trishydroxyethylhexahydro-S-triazine was added to the washing water, and the PS processor PS-900NP was added to PS-900. 900
Except for changing to V, the same processing as in Reference Example 1 was performed, and the final plate was used as a printing sample. The PS Processor PS-900NP was replaced with PS-900V was printed sample the last version performs exactly the same processing as in Reference Example 1 Reference Example 3 Reference Example 1. Examples 5 and 6 In Reference Example 3 , 7 g of compound [I] -2 was used,
A printing sample was prepared in exactly the same manner as in Reference Example 3 , except that 7 g of Compound [I] -3 was added. Example 7 In Reference Example 2 , 7 g of compound [I] -4 was added,
1,3,5-trishydroxyethylhexahydro-S
-Instead of 7 g of triazine, 7 g of 3-methyl-4-isopropylphenol and 3 g of diethylene glycol
Except that 5 g was added, the same processing as in Reference Example 2 was performed, and the last plate was used as a printing sample. COMPARATIVE EXAMPLES 1 AND 2 In Examples 1 and 4 , only tap water was used in the water washing section, except that the same treatment as in Examples 1 and 4 was performed, and the last plates were used as printing samples. In order to evaluate the ink adhesion of the printing samples of Examples 1 to 7, Reference Examples 1 to 3, and Comparative Examples 1 and 2, the samples were previously left at 35 ° C. and 85% for 3 days. .
The samples were mounted on a Harris Aurelia 125 offset printing press and printing commenced according to conventional methods. The number of prints until the ink adhered to the image area and a good printed matter was obtained is shown in the column of ink adhesion in Table 1. [Table 1] [0026] Formula (I) as an additive compound according to the result, the compound added with the system to wash water [II] (Example 1-7) has been excellent in ink receptivity, washing water (Comparative Examples 1 and 2) using only tap water was inferior in the ink deposition property. In addition, these additive compounds also acted as fungicides, and were also effective in preventing decay of the washing section. Further, in the PS-900V of Example 4, Reference Example 2, Reference Example 3, Examples 5, 6 and 7 , due to its mechanism, the washing water to which the additive of the present invention was added was supplied from the supply tank to the developing solution. It is also used as a diluting water for finishing gums and finishing rinses, but their performance was not affected at all. The additive for rinsing water of a lithographic printing plate according to the present invention has an effect of preventing a decrease in the inking property at the start of printing of the lithographic printing plate.

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-3-218895 (JP, A) JP-A-6-43700 (JP, A) JP-A-63-172269 (JP, A) JP-A-51- 127082 (JP, A) JP-A-51-82378 (JP, A) JP-A-54-27569 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03F ^7/ 00-7 / 42

Claims (1)

(57) [Claims] [Claim 1] Image-sensitizing a photosensitive lithographic printing plate;
A step of developing and a step of washing with water after the step of developing
And providing a hydrophilic plate surface protective layer on the printing plate.
In the method of making a lithographic printing plate,
The washing water is represented by the following general formula [I] or [II]
Of a photosensitive lithographic printing plate characterized by containing a compound
Plate making method. Embedded image