JPH0331251B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention is a lithographic printing plate material (offset and
This invention relates to a developer for PS plates (PS plates), and in particular to a developer for removing non-image areas after exposing an acrylic offset PS plate whose photosensitive material contains a diazo compound and a carboxylic acid. [Prior art] Almost all PS plates for negative offset currently on the market contain a diazo compound, typified by a formaldehyde condensate of P-diazophenylamine, and a carboxylic acid blended for the purpose of strengthening the image area. It is composed of a photosensitive resin composition made of an acrylic multi-component copolymer and an aluminum plate with surface hydrophilicity. (Tokuko Showa 52-7364, Tokuko Showa
56-4144). In the process of making a lithographic printing plate using such a PS plate, the extremely important role of the developer is to quickly dissolve and remove the photosensitive resin layer in the non-image area, and also to remove the exposed aluminum surface by development. The objective is not to reduce the hydrophilicity of the resin, but rather to enhance it, while not impairing the lipophilicity of the resin layer in the image area that has been cured by actinic rays. [Problems to be Solved by the Invention] However, promoting the hydrophilicity of non-image areas, which is the required role of the developer, may conversely reduce the lipophilicity of image areas, and the development speed may be reduced. If you try to increase the image area, the image area will also be relatively eluted, causing problems with image reproducibility.
Various measures are required, and in reality, staining of the plate during printing and poor inkling at the beginning of printing are often caused by the developer. The inventor has developed his own acrylic offset PS.
While conducting research to improve the developer for printing plates, we arrived at a new developer that is perfect in terms of development speed and ability to maintain the hydrophilicity of the aluminum surface in non-image areas. [Means and effects for solving the problem] That is, the present invention solves _the problem by solving _the following problems:
(wherein R represents a phenyl group or a benzyl group) - hereinafter referred to as "specific ether compound" - for photosensitive lithographic printing plates characterized by containing an anionic surfactant and an alkaline substance. It provides a developer. More specifically, the specific ether compound in the present invention is ethylene glycol monophenyl ether (

[Formula]) and ethylene glycol monobenzyl ether (

[Formula]) These are organic solvents and are commercially available. As the anionic surfactant used in the present invention,
Fatty acid salt {(R ¹ COO) _o Mm}, alkylbenzene sulfonate {

[Formula]} Alkyl sulfonate {(R ¹ −SO ₃ ) _o Mm}, α-
Olefin sulfonate {

【formula】

Mixture of [formula], etc.}, dialkyl sulfosuccinate {

[Formula] α-sulfonated fat Fatty acid salts {

[Formula] }N-methyl-N-oleyl taurine {

[Formula]} Alkyl phosphorus Acid acid {

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to examples and the like. Example 1 400 gr of butyl cellosolve was injected into a clean 1-volume glass reaction vessel equipped with a backflow condenser in advance, and stirred while flowing nitrogen into the reaction vessel.
Heat the reaction vessel from the outside. When the temperature of butyl cellosolve reaches 80°C, the following composition is dropped into the reaction vessel from the upper funnel at a rate of 1gr/min to react. At this time, the reaction temperature is adjusted within the range of 80 to 86°C. Methyl methacrylate 45g Styrene 10g Acrylic acid 40g 2.W polybutadiene glycol 5g (Number average molecular weight 1350±50 Nippon Soda Products G-1000) Azobisisobutyronitrile 2g Reaction time is 4 from the start of dropping the above composition
After the reaction was completed for ~5 hours, 60 g of 2-methoxy-4-hydroxy-5-benzoinbenzenesulfonic acid, a condensate of P-diazodiphenylamine and paraformaldehyde, and Oil Blue #603 were added to the quaternary copolymer solution at room temperature. After adding 0.05g of ethylenediaminetetraacetic acid (EDTA) and 1.6g of ethylenediaminetetraacetic acid (EDTA) and 240g of butyl cellosolve and stirring and mixing at room temperature for 3 hours, Toyo Shi 12.5CM-
Suction through 131. Next, 250 g of the obtained liquid was diluted with a mixed solvent consisting of 1500 g of isopropyl alcohol, 200 g of xylene, and 200 g of ethyl complex acid to prepare a photosensitive resin composition solution. Next, this photosensitive resin composition solution was coated on an aluminum 2S material with a thickness of 0.25 m/m, which had been surface-roughened and hydrophilized in advance, using a bar coater No. 6, and then dried in a hot air dryer at 100°C. A photosensitive resin plate was prepared by drying for 3 minutes. The dry coating weight was 2.0 g/m ² . This photosensitive resin plate was exposed to light for 20 seconds from a distance of 1 m using a 4KW ultra-high pressure mercury lamp through a negative image in a vacuum printing frame, and then immersed in the following developer for 1 minute at room temperature, taken out, washed with water, dried, and plated. Got the print version. Ethylene glycol monophenyl ether 20g Sodium alkylnaphthalene sulfonate 10g Sodium triphosphate 20g Water 950g When this printing plate was printed on high-quality paper using a Heidel GTO printing machine, more than 100,000 copies were printed. Next, we looked at the development width at 20°C with this developer. As a result, the gray scale sensitivity remained stable with no change from development time of 20 seconds to 10 minutes. However, as soon as the development time was extended for more than 10 minutes, fading of the image area was observed, but no abnormality was observed in the sensitivity. In addition, the exposed PS plate was developed using the above-mentioned developer at 20°C for 30 seconds in an automatic processing machine called Auto Processor 600E (manufactured by Fuji Photo Film Co., Ltd.), and the processing performance at that time was investigated. 17m ² /
That's all. Approximately 10m ² / with conventional developer
was the limit, and compared to this, the processing capacity was extremely high. Comparative Example 1 The PS plate produced in Example 1 was exposed to light for 20 seconds from a distance of 1 m using a 4KW ultra-high pressure mercury lamp through a negative image in a vacuum printing frame, and then processed with the following developer at room temperature.
After being immersed for a minute, it was taken out and washed with water, but the non-image area could hardly be removed. Ethylene glycol monophenyl ether 20g Emulgen 106 (polyoxyethylene lauryl ether) 20g Trisodium phosphate 10g Water 950g Comparative example 2 The PS plate produced in Example 1 after exposure was used in the following developer for 1 minute at room temperature. After immersion, it was taken out and washed with water, but the non-image area could hardly be removed. Ethylene glycol monophenyl ether 20g Colomine E-331 (stearylamine oleate) 20g Sodium carbonate 10g Water 950g Comparative example 3 The PS plate produced in Example 1 after exposure was developed in the following developer for 1 minute at room temperature. Take out after soaking,
Although it was washed with water, the non-image area could not be completely removed. Ethylene glycol monophenyl ether 20g Amhitol 24B (lauryl betaine)
20g Sesquicarbonate soda 10g Water 950g Examples 2 to 10 The PS plate produced in Example 1 was passed through a negative image in a vacuum printing frame from a distance of 1m using a 4KW ultra-high pressure mercury lamp.
After exposure for 20 seconds, a lithographic printing plate was obtained using the developer shown in Table 1. The results are also shown in the same table.

【table】

[Table] Example 11 The PS plate prepared in Example 1 was printed through a negative image in a vacuum printing frame from a distance of 1 m using a 4KW ultra-high pressure mercury lamp.
After exposure for 20 seconds, the following developer was used at room temperature.
After being immersed for a minute, it was taken out, washed with water, and dried to obtain a lithographic printing plate. Ethylene glycol monobenzyl ether 20g Beretskus NB-L 20g Water glass (solid content 50%) 10g Shihosan soda 5g Water 945g Using this printing plate, printing was carried out in accordance with Example 1, and as a result, more than 100,000 copies were printed. In addition, the development width at 20°C is extremely excellent.
The gray scale sensitivity was stable without any change up to 30 minutes, and no fading of the image area was observed even when the development time was extended beyond 30 minutes. Also, no abnormality was observed in sensitivity. Also, when I investigated the development processing capacity, it was 17
m ² / or more, which was almost the same as in Example 1. Examples 12 to 28 After exposing the PS plate prepared in Example 1 to light in the same manner as in Example 11, a lithographic printing plate was obtained using the developer shown in Table 2. The results are also shown in the same table. The meanings of *1 and *2 in the table are as follows. *1 A: Ethylene glycol monophenyl ether B: Pellex NB-LC C: Water glass (solid content 50%) / Tetra-hosan soda = 4/1 *2 The non-image area after immersed in a developer for 18 hours, washed with water and dried Contact angle (by goniometer)

[PS version used]

(1) Almax TAN Manufactured by Ohka Kogyo Co., Ltd. (2) FNC-B Manufactured by Fuji Photo Film Co., Ltd. (3) SWN Manufactured by Konishiroku Photo Co., Ltd. (4) Ulster NS Manufactured by Nippon Seifaku Co., Ltd. (1) N-200 Manufactured by Ohka Kogyo Co., Ltd. (2) DN-3C Manufactured by Fuji Photo Film Co., Ltd. (3) SDN-21 Manufactured by Konishiroku Photo Co., Ltd. (4) Present invention *Development Pour 100 ml of developer into a stainless steel vat with bottom dimensions of 15 cm x 18 cm, insert a PS plate (raw plate) with dimensions of 10 cm x 10 cm, soak it, take it out every 10 seconds, wash it with water, and coat the surface of the plate with protect ink. It is indicated by the immersion time when no wipe stains are observed.

[Table] Experimental Example 2 Add 100 ml of each commercially available developer to the development rate measurement vat used in Experimental Example 1, leave it for 18 hours at 40°C, then add the amount of water that decreased due to the standing, and then The development speed was measured in the same manner.
The results are shown in Table 4, and in the case of the present invention, there was almost no deterioration in the developing effect due to leaving the developing solution.

[Table] Experimental Example 3 Commercially available PS was included in the various developers used in Experimental Example 1.
The plates (raw plates) FNC-B and Ulster NS were immersed, the container was sealed, and the plates were immersed for 24 hours at room temperature, then the PS plates were taken out, developed, the exposed aluminum surface was washed with water, and air-dried indoors for 4 hours. Next, the color change of the aluminum surface was observed, and the contact angle with water was measured using a goniometer. The results are shown in Tables 5 and 6, and it was found that the developed solution according to the present invention does not discolor the aluminum surface, has a small contact angle, and is an excellent developer that hardly causes any trouble to non-image areas. .

[Table] Surface properties

【table】

Claims (1)

[Claims] 1. Characterized by containing an ether compound represented by the general formula R-O-CH ₂ CH ₂ OH (wherein R represents a phenyl group or a benzyl group), an anionic surfactant, and an alkaline substance. A developer for photosensitive lithographic printing plates. 2. The developer for photosensitive lithographic printing plates according to claim 1, wherein the anionic surfactant is an alkylnaphthalene sulfonate. 3. The developer for a photosensitive lithographic printing plate according to claim 1, wherein the alkaline substance comprises water glass and tetraphosane salt.