JPH04264556A - Development processing method for photosensitive planographic printing plate - Google Patents

Abstract

PURPOSE:To enable the good development of both of plates different in plate kinds to be carried out with one unit of automatic developing machine and to facilitate the control thereof. CONSTITUTION:This method consists in subjecting both of the PS plate and dampening waterless photosensitive planographic printing plate to development processing with one unit of the automatic developing machine and is the method for subjecting the PS plate and the dampening waterless photosensitive planographic printing plate to the development processing by increasing the rotating circumferential speed of the developing brush roller 31 of the dampening waterless photosensitive planographic printer plate than the rotating circumferential speed of the PS plate or by varying the transporting speeds at the time of the development processing of the PS plate and the dampening waterless photosensitive planographic printing plate. The plate kinds are detected by a plate kind discriminating sensor 6. The rotating circumferential speed of a developing brush roller 31 of, for example, a brush driving device 18 is so set as to attain 10m/min at the time of the PS plate and 100m/min at the time of the dampening waterless photosensitive planographic printing plate. The transporting speed is set at 180cm/min in the case of the PS plate and at 60cm/min in the case of the dampening waterless photosensitive planographic printing plate at the time of changing the transporting speed.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to a method for developing photosensitive planographic printing plates, and more specifically, the present invention relates to a method for developing photosensitive planographic printing plates, and more specifically, the present invention relates to a method for developing photosensitive planographic printing plates, such as PS plates or photosensitive planographic printing plates that do not require dampening water. The present invention relates to a method for developing a photosensitive lithographic printing plate, which can be easily and easily developed using an automatic developing machine, at low cost, and with good working efficiency.

0002

BACKGROUND OF THE INVENTION Conventionally, printing plates include PS plates, which have a photosensitive layer laminated on a roughened and hydrophilic support, and photosensitive plates, which do not require dampening water, and which have a photosensitive layer and a silicone rubber layer on a support. However, in order to obtain a printing plate by developing these PS plates and photosensitive lithographic printing plates that do not require dampening water, the composition of the developer and the development conditions are usually different, so each needs to be prepared separately. A developing machine was used.

That is, an aqueous alkaline developer is generally used as a developer for a PS plate, whereas a polar organic solvent or a non-polar organic solvent is often used in a photosensitive lithographic printing plate that does not require dampening water. However, recently, JP-A-61-275
As described in No. 759 and Japanese Unexamined Patent Publication No. 1-257847, the technology of using an alkaline developer containing water as a main component has become known even in photosensitive lithographic printing plates that do not require dampening water. It has become possible to develop both PS plates and photosensitive lithographic printing plates that do not require dampening water using a developer that is common to PS plates.

However, the PS plate and the photosensitive lithographic printing plate that do not require dampening water have different development modes. That is, the development of a PS plate consists of substantially dissolving the image area, whereas the development of a photosensitive lithographic printing plate that does not require dampening water involves applying strong rubbing during development to dissolve the image. It is necessary to scrape off the silicone rubber layer on the surface. As described above, since PS plates and photosensitive lithographic printing plates that do not require dampening water use different development methods, it is extremely difficult to develop them both with one automatic developing machine. The technology is still unknown.

[0005] If a PS plate and a photosensitive lithographic printing plate that does not require dampening water are developed using an alkaline developer in one automatic processor, normally the photosensitive lithographic printing plate that does not require dampening water will be Developability is often poor, so if both plates are developed at the same transport speed, one of the plates will be overdeveloped or underdeveloped. Therefore, the transport speed of the plate during development is P
When matched with the S plate, the PS plate can be developed well, but with a photosensitive lithographic printing plate that does not require dampening water, the development is insufficient and a silicone rubber layer remains in the image area.

On the other hand, if the transport speed of the plate is increased and the rubbing is strengthened in accordance with the development conditions of the photosensitive planographic printing plate that does not require dampening water, good development can be achieved with the photosensitive planographic printing plate that does not require dampening water. However, the disadvantage is that the device becomes large and the cost is high. In particular, a method in which the brush pressure is increased only for photosensitive lithographic printing plates that do not require dampening water is difficult to control and does not provide stable developability. If such conditions are applied to a PS plate, brush scratches will occur in the printed area or thin lines will be missing, making it impossible to obtain a good plate.

Furthermore, when the PS plate and the photosensitive lithographic printing plate that do not require dampening water are developed at the same conveyance speed, the PS plate may have scratches or defects in the image area, or the photosensitive lithographic printing plate that does not require dampening water may be damaged. The problem with printing plates is that the reproducibility of shadow areas is reduced. Furthermore, when using the same alkaline developer, if the rubbing by the developing brush roller during development is matched to that of the PS plate, the PS plate can be developed well, but with a photosensitive lithographic printing plate that does not require dampening water, the development is insufficient. The silicone rubber layer remains in the area that will become the image area.

On the other hand, if the rubbing by the developing brush roller is strengthened in accordance with the development conditions of the photosensitive planographic printing plate that does not require dampening water, good development can be achieved with the photosensitive planographic printing plate that does not require dampening water. However, for PS plates, brush scratches occur in the printed areas and thin lines are missing, making it impossible to obtain a good plate.

On the other hand, under such circumstances, a method can be considered to change the rubbing strength during development between the PS plate and the photosensitive lithographic printing plate that does not require dampening water. For example, by moving the developing brush up and down,
When developing the plate, there is no need for dampening water. When developing a photosensitive lithographic printing plate, there is a method of contacting the plate more firmly, or by arranging multiple developing brush rollers, which eliminates the need for dampening water.

[
[0010] When developing a photosensitive planographic printing plate, all the developing brush rollers are operated, and when developing a PS plate, fewer developing brush rollers (for example, one) are used.
However, in these methods, the apparatus becomes large-scale and the cost increases, and furthermore, it is difficult to control the developing brush roller, etc., and stable development cannot be obtained.

[0011] Therefore, as a result of various studies in addition to these methods, the present inventors have determined whether the difference in development conditions between a PS plate and a photosensitive lithographic printing plate that does not require dampening water can be achieved by changing the transport speed of the plate. , or by changing the rotational peripheral speed of the developing brush roller, it has been found that both PS plates and photosensitive lithographic printing plates that do not require dampening water can be developed well, and development with excellent development stability can be achieved, and the present invention is hereby accomplished. completed.

0012

OBJECTS OF THE INVENTION The first object of the present invention is to be able to successfully develop both a PS plate and a photosensitive lithographic printing plate that does not require dampening water using one automatic developing machine, and which does not require a large-scale equipment. Another object of the present invention is to provide a method for developing a photosensitive lithographic printing plate that is not only low-cost but also low-cost. A second object of the present invention is to provide a method for developing a photosensitive lithographic printing plate, which allows easy control of an automatic processor, has excellent development stability, and has excellent work efficiency.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The above objects of the present invention are achieved as follows. (1) In a method of developing both a PS plate and a photosensitive lithographic printing plate that does not require dampening water using an automatic developing machine having at least one developing brush roller, the photosensitive lithographic printing plate that does not require dampening water is A development process for a photosensitive lithographic printing plate, characterized in that the development process is carried out at a rotational circumferential speed of the development brush roller that is greater than the rotational circumferential speed of the development brush roller during the development process of a PS plate. Method.

(2) A plate type discrimination sensor for determining either the PS plate or the photosensitive lithographic printing plate that does not require dampening water as described in item 1 is provided at an appropriate location before development to detect the plate type and automatically 1. A method for developing a photosensitive lithographic printing plate, comprising changing the rotational peripheral speed of a developing brush roller.

(3) In a method in which both the PS plate and the photosensitive lithographic printing plate that do not require dampening water are developed using one automatic developing machine, the transport speed and dampening water during the development processing of the PS plate are 1. A method for developing a photosensitive lithographic printing plate that does not require water, the method comprising changing the conveyance speed during the development process of the photosensitive lithographic printing plate.

(4) The transport speed during the development process of the PS plate described in item 3 is 1 of the transport speed of the photosensitive lithographic printing plate that does not require dampening water.
1. A method for developing a photosensitive lithographic printing plate, characterized in that the development process is in the range of /6 to 4/6. (5) Either the PS plate or the photosensitive lithographic printing plate that does not require dampening water as described in item 3 or 4 is installed with a plate type discrimination sensor at an appropriate location before the development process to detect the plate type and automatically 1. A method for developing a photosensitive lithographic printing plate, characterized by varying the conveyance speed.

The configuration of the present invention will be specifically explained below. The present invention provides a method for changing the transport speed during development of a PS plate and the transport speed during development of a photosensitive lithographic printing plate that does not require dampening water, or when developing a photosensitive lithographic printing plate that does not require dampening water. By performing the development process at a rotational speed of the developing brush roller that is higher than the rotational speed of the developing brush roller during the development process of the PS plate, both the PS plate and the photosensitive lithographic printing plate that does not require dampening water can be produced. can be developed satisfactorily with one automatic developing machine, and the cost can be reduced without making the equipment large-scale.

[0018] Furthermore, the present invention provides a plate type discrimination sensor for discriminating between a PS plate and a photosensitive lithographic printing plate that does not require dampening water at an appropriate location before the development process to detect the plate type and automatically transport the plate. By changing the speed or automatically changing the rotational circumferential speed of the developing brush roller, the automatic developing machine can be easily controlled, has excellent developing stability, and has excellent work efficiency. The photosensitive planographic printing plate used in the present invention is used to include two types of photosensitive planographic printing plates: PS plates and photosensitive planographic printing plates that do not require dampening water.

In the present invention, the rotational peripheral speed of the developing brush roller set during the development process of the PS plate and the rotational peripheral speed of the developing brush roller set during the development process of the photosensitive lithographic printing plate that does not require dampening water are different. Therefore, the rotational peripheral speed of the developing brush roller set during the development process of the PS plate is 0.
．． The rotation speed of the developing brush roller is preferably 5 to 30 m/min, and the rotational speed of the developing brush roller is set in the range of 35 to 150 m/min during the development process of the photosensitive lithographic printing plate that does not require dampening water.

Furthermore, the ratio of the rotational peripheral speed of the developing brush roller set during the development processing of the PS plate to the rotational peripheral speed of the developing brush roller set during the development processing of the photosensitive lithographic printing plate that does not require dampening water is 1/ The range of 100 to 1/2 is preferable. In the present invention, the plate conveyance speed set during the development process of the PS plate is different from the plate conveyance speed set during the development process of the dampening water-free photosensitive lithographic printing plate. The plate transport speed set during processing is 12
0 to 300 cm/min, preferably 150 to 2
00cm/min.

[0021] Furthermore, the plate transport speed set during the development process of the photosensitive lithographic printing plate that does not require dampening water is 20 to 100 cm/
min, preferably in the range of 30 to 70 cm/min. The plate type discrimination sensor used in the present invention is one that detects the physical properties, shape, etc. of the front or back surface of a PS plate or a photosensitive lithographic printing plate that does not require dampening water to determine its type. Examples include photoelectric sensors.

The plate type discrimination sensor used in the present invention is
It is installed at the insertion part of an automatic developing machine or before it, and if one type of plate is processed while another type of plate is being processed, the peripheral speed of the developing brush rotation or conveyance speed may change, making it difficult to maintain proper Therefore, in order to prevent such erroneous processing, it is preferable to install a warning buzzer or a warning lamp to prevent plates of different types from being processed during processing. Alternatively, an indicator lamp may be provided to indicate whether the plate being processed is a PS plate or a photosensitive lithographic printing plate that does not require dampening water.

When the developer used in the present invention is used for a long period of time, it becomes fatigued and its performance fluctuates, so it is preferable to replenish the developer. For replenishment, it is preferable to measure the distance between the longitudinal direction and the width direction of the plate using a plurality of plate detection sensors arranged in the width direction in the insertion portion, calculate the area, and perform replenishment according to the plate area. The developer used in the present invention is commonly used for PS plates and photosensitive lithographic printing plates that do not require dampening water, and is an aqueous developer.

The organic solvent contained in the water-based developer used in the present invention, the so-called aqueous developer, is as follows:
For example, aliphatic hydrocarbons (hexane, heptane, Isopar E, H, G (manufactured by Esso Chemical Co., Ltd., product name of aliphatic hydrocarbons or gasoline, kerosene, etc.), aromatic hydrocarbons (toluene, xylene, etc.) , or halogenated hydrocarbons (tricrene, etc.), alcohols (methanol, ethanol, 1-butoxy-2-propanol, 3-methyl-3-methoxybutanol, β-anilinoethanol, benzyl alcohol, etc.),

Ethers (methyl cellosolve, ethyl cellosolve, butyl cellosolve, phenyl cellosolve, methyl carbitol, ethyl carbitol, butyl carbitol, dioxane, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, ethylene glycol dibutyl ether, propylene glycol, dipropylene glycol butyl ether, tripropylene glycol methyl ether, polypropylene glycol methyl ether, etc.),

Ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, 4-
methyl-1,3-dioxolan-2-one, etc.), esters (ethyl acetate, propyl acetate, hexyl acetate, methyl acetate, propyl acetate, diethyl succinate, dibutyl oxalate, diethyl maleate, benzyl benzoate, methyl cellosolve acetate) , cellosolve acetate, carbitol acetate, etc.). Among these, preferred are organic solvents having a solubility in water of 1% by weight or more, and the amount added is from 0.1% to 20% by weight.

As the surfactant added to the developer used in the present invention, anionic surfactants, nonionic surfactants, cationic surfactants and amphoteric ionic surfactants are used. The surfactants described in specification No. 206041 are used. These surfactants can be used alone or in combination of two or more.

The appropriate amount of the surfactant used in the present invention is 0.01% to 60% by weight, preferably 0.1% to 10% by weight. PS used in the present invention
The photosensitive layer of a photosensitive lithographic printing plate that does not require a plate or dampening water is as follows:
Those commonly used in the technical field of lithographic printing plates, such as diazo compounds, diazide compounds, photopolymerizable compounds, photocrosslinkable compounds, and photosoluble compounds, are used.

As the silicone rubber layer, polyorganosiloxane or the like, which is generally used in the technical field of photosensitive lithographic printing plates that do not require dampening water, is used. Further, it is preferable to add an inorganic or organic alkaline agent to the developer used in the present invention, and it is preferable to use the developer at a pH of 9 to 10.

[0030]

EXAMPLES The present invention will be explained in more detail below using Examples, but the present invention is not limited to these Examples. Example 1 [Synthesis of diazo resin -1] 14.5 g (50 mmol) of p-diazodiphenylamine sulfate was mixed with 40.0 g of p-diazodiphenylamine sulfate under ice cooling.
Dissolved in 9g of concentrated sulfuric acid. Add 1.35g (4
5 mmol) of paraformaldehyde at a reaction temperature of 10
It was added gradually so as not to exceed ℃.

This reaction mixture was added dropwise to 500 ml of ethanol under ice cooling, and the resulting precipitate was filtered. After washing with ethanol, this precipitate was dissolved in 100 ml of pure water, and a cold concentrated aqueous solution containing 6.8 g of zinc chloride was added to this solution. After filtering the resulting precipitate,
It was washed with ethanol and dissolved in 150 ml of pure water.

To this liquid was added a cold concentrated aqueous solution in which 8 g of ammonium hexafluorophosphate was dissolved. The resulting precipitate was collected by filtration, washed with water, and then dried to obtain diazo resin-1. The styrene-equivalent weight average molecular weight (Mw
) was 1500, and the number average molecular weight was 500.

[Preparation of photosensitive lithographic printing plate-1 that does not require dampening water] The following primer layer composition was coated at 60°C with a whirler on a degreased aluminum plate with a thickness of 0.24mm, and then heated at 100°C. After drying for 2 minutes, a primer layer was applied. Note that the primer layer composition was dispersed using a high-pressure bulb homogenizer.

[Primer layer composition] (1) Copolymer resin (M
w=4.0×104)
100 parts by weight (2) Pentaerythritol triacrylate
80 parts by weight (3) DE
TX (manufactured by Nippon Kayaku Co., Ltd.)
3 parts by weight

[0035]

[Chemical formula 1]

(4) EPA (manufactured by Nippon Kayaku Co., Ltd.)
3 parts by weight

[0037]

[Case 2]

(5) Kett Yellow 402 (manufactured by Dainippon Ink Co., Ltd.)
Yellow pigment) 8 parts by weight (6) Zinc oxide (average particle size
0.12μ)
20 parts by weight (7) Ethyl cellosolve

After coating and drying 920 parts by weight, exposure was performed using Unicure (manufactured by Ushio Inc.) at 160 W and 4 m/min. Next, the following photosensitive composition was applied onto the primer layer and dried at 80° C. for 2 minutes to form a photosensitive layer with a thickness of 0.3 μm.

[Photosensitive composition] (1) Diazo resin-1
10
0 parts by weight (2) 2-hydroxyethyl methacrylate,
A copolymer resin (Mw
=4.2×104) 100 parts by weight (3) Orange IV

8 parts by weight (4
) Methyl lactate
90
0 parts by weight of the silicone rubber composition shown below was then coated on the photosensitive layer to a thickness of 2.0/m<2> and dried at 90 DEG C. for 10 minutes.

[Silicone rubber layer composition] (1) Dimethylpolysiloxane having hydroxyl groups at both ends (molecular weight 52,000)
100
Part by weight (2) The following reactive silane compound
2.5 parts by weight

[0041]

[Chemical formula 3]

(3) Dibutyltin dilaurate
0.8 parts by weight (4) Isopar E (manufactured by Esso Chemical)
900 parts by weight Next,
A 6μ thick polypropylene film is laminated on the silicone rubber layer to form a photosensitive lithographic printing plate that does not require dampening water.
I got 1.

[Preparation of photosensitive lithographic printing plate-2 that does not require dampening water] (Synthesis of polymer) 150 g of 2-hydroxyethyl methacrylate, 60 g of acrylonitrile, 79.5 g of methyl methacrylate, 10.0 g of methacrylic acid (the molar ratio of each is 37:35:24:4) in distilled dioxane 7
00g (total monomer concentration: 4.5 mol/L)
15 g (2 mol %) of benzoyl peroxide was gradually added, and a polymerization reaction was carried out for 8 hours under reflux in a nitrogen stream.

After the reaction was completed, 0.5 g of hydroquinone was added, and the solvent was distilled off under reduced pressure. When the viscosity increased, it was poured onto a stainless steel plate and vacuum dried to give 270 g.
A plate-shaped resin (polymer) was obtained. The GPC measurement values of the polymer are shown below. Mw: 4.80×104, dispersion ratio: 2.2

0045
] The degreased and cleaned aluminum plate was anodized in a 40% by weight sulfuric acid aqueous solution at a temperature of 30°C and a current density of 1.5A/dm2 for 2 minutes, washed with water, and then anodized in a 1% by weight sodium silicate aqueous solution. The substrate was treated with sodium silicate for 25 seconds at 0.degree. C., and then washed with water to obtain a printing plate substrate. A primer layer composition having the following composition was applied to this substrate at 5.5°C using a whirler, and dried at 85°C for 3 minutes to form a primer layer. The dry film thickness was 10 mg/dm2.

[Primer layer composition] (1) Polymer (alcoholic hydroxyl group-containing polymer)
100 parts by weight (2) Diazo resin-1
(p-diazodiphenylamine/formaldehyde resin)
20 parts by weight (3) Methyl cellosolve
2400 parts by weight

004
7] Next, apply 3KW to the aluminum plate coated with the above composition.
The entire surface was exposed to light at 100 mJ/m2 using an ultra-high pressure mercury lamp. The aluminum plate coated with the primer layer thus obtained did not dissolve even when immersed in a photosensitive layer coating solvent (methyl cellosolve) or a developer.

[0048] When the UV integrating sphere was measured using a Hitachi spectrometer 3200 and the decomposition rate of diazo was measured, it was found that the diazo absorption part at 378 nm was completely decomposed by the above exposure. On the aluminum plate coated with the above primer layer, apply 3 mg/dry weight of the following photosensitive composition.
dm2 at 55° C. and dried to form a photosensitive layer.

[Photosensitive composition] (1) Polymer (alcoholic hydroxyl group-containing polymer)
100 parts by weight (2) Diazo resin-1
(p-diazodiphenylamine formaldehyde resin)
10 parts by weight (3) Victoria Pure Blue BOH
2 parts by weight (4) Methyl cellosolve
2400 parts by weight (5) Ethyl cellosolve
1000 parts by weight Next, 15 parts by dry weight of the following silicone rubber composition was applied on the photosensitive layer.
A silicone rubber layer was formed by coating with a whirler at 55° C. and drying to give a concentration of mg/dm 2 .

[Silicone rubber composition] (1) YF-3057 manufactured by Toshiba Silicone
100 parts by weight (2) Toshiba Silicone TSL-8180
10 parts by weight (3) Aerosil R-972 (manufactured by Nippon Aerosil Co., Ltd.)
3 parts by weight (4) di-n-butyltin dilaurate
0.8 parts by weight (5) Hexane

A single-sided matted polypropylene film having a thickness of 5 μm was laminated on the surface of the silicone rubber layer obtained in an amount of 1400 parts by weight to obtain a photosensitive lithographic printing plate-2 that does not require dampening water.

[Preparation of positive PS plate] Thickness 0.24 mm
A JIS-1050 aluminum plate was immersed in a 2% aqueous sodium hydroxide solution for degreasing, then electrochemically roughened in a dilute nitric acid solution, thoroughly washed, and anodized in a dilute sulfuric acid solution. The treatment was carried out to form an oxide film of 2.5 g/m2 on the surface of the aluminum plate. After washing and drying the aluminum plate thus treated, a photosensitive coating liquid having the following composition was applied to the plate at a dry weight of 2.5 g/m 2 and dried to obtain a positive PS plate.

[Photosensitive coating liquid composition] (1) Naphthoquinone-(1,2)-diazide-(2)-
Ester compound of 5-sulfonic acid chloride and pyrogallol acetone resin (compound described in Synthesis Example 2 of JP-A-60-143345)

2 parts by weight

(2) Copolymer resin of phenol, m-, p-mixed cresol, and formaldehyde (phenol during synthesis,
The charging molar ratio of m-cresol and p-cresol was 20:48:32, and the weight average molecular weight Mw=
7400, number average molecular weight Mw=1400)

6.5 parts by weight

(3) Ester compound of novolak resin synthesized from p-tert-octylphenol and formaldehyde and naphthoquinone-(1,2)-diazide-(2)-5-sulfonic acid chloride (condensation rate: 50 mol%) , Mw=1700) 0.
1 part by weight (4) Victoria Pure Blue BOH (manufactured by Hodogaya Chemical Co., Ltd.) 0.08 part by weight

(5) Ethyl cellosolve
8
0 parts by weight (6) Methyl cellosolve

20 parts by weight After vacuum adhering the positive film to each of the above plates, 4 parts by weight were applied using a metal halide lamp as a light source.
00 mJ/m2 exposure. This exposed plate is shown in Figure 1.
The image was developed using an automatic processor shown in .

Into the developing tank 9 of the automatic developing machine shown in FIG. 1, 20 liters of positive-type PS plate developer "SDR-1" manufactured by Konica Corporation diluted 6 times with water was charged and heated to 30°C. I tuned it. A washing tank 10 next to the developing section was filled with 18 liters of tap water as washing water. A surfactant or an acid may be added to this washing water to enhance the rinsing effect.

In the dyeing tank 11, which is the next step after the washing section, 3 parts by weight of benzyl alcohol and 0.0 parts by weight of crystal violet were added.
20 liters of a dyeing solution consisting of 5 parts by weight and 100 parts by weight of water was charged and the temperature was controlled at 35°C. Furthermore, 10 liters of tap water was charged into the washing tank 12 next to the dyeing section. The squeezing roll in this washing section was a Morton roll 4 wrapped with a cloth-like material to improve liquid removal.

First, a plate type discrimination sensor 6 and a plate detection sensor 7 are installed in the insertion part of the automatic developing machine, and these sensors determine whether the plate is a PS plate or if it is a photosensitive lithographic printing process that does not require dampening water. It is detected if it is a plate, and this signal causes the brush drive device 18 connected to the control device 17 to be activated. This drive device 18 controls the rotation peripheral speed of the developing brush.
When the signal of the PS plate is detected in advance, the brush rotation peripheral speed of the PS plate is changed, and when the signal of the photosensitive planographic printing plate that does not require dampening water is detected, the brush rotation of the photosensitive planographic printing plate that does not require dampening water is adjusted. Each is automatically set to match the circumferential speed.

Specifically, in the case of a PS plate, the developing brush rotation peripheral speed is 10 m/min, and in the case of a photosensitive planographic printing plate that does not require dampening water, the developing brush rotation peripheral speed is 100 m/min.
/min. The brush roller 31 used for development has a diameter of 80 mm, and the material of the brush bristles is polybutylene terephthalate, and the thickness of the bristles is 0.24 mm.
, consists of a channel type brush with bristles of 16 mm in length, 3
I used a book. The direction of rotation was forward rotation for all three.

The conveying speed of the plate was 800 mm/min both during processing of the PS plate and during processing of the photosensitive lithographic printing plate that did not require dampening water, and the developing time was 50 seconds. Here, the developer replenisher is
Konica Corporation's developer replenisher for positive PS plates "SDR"
-1R'' stock solution diluted 4 times with dilution water and supplied. The replenishment amount of the developer replenisher was 50 ml/m2 for both the PS plate and the photosensitive lithographic printing plate that does not require dampening water. Further, the shower replenishment amount was 500 ml/hr, and the daily replenishment amount was 50 ml/hr.

When a large number of positive PS plates and photosensitive lithographic printing plates that do not require dampening water were processed in succession using an automatic developing machine with the conditions set as described above, both plates were developed without excess or deficiency. A good plate was obtained. In addition, since the plate to be processed is automatically detected by the plate type discrimination sensor, the operator can work without worrying about the plate type, and work efficiency is further improved by preventing erroneous processing.

Example 2 Photosensitive lithographic printing plate-1 that does not require dampening water was prepared in the same manner as in Example 1.
After manufacturing a photosensitive lithographic printing plate-2 that does not require dampening water and a positive-working PS plate, a positive film was vacuum-adhered to these plates, and then a metal halide lamp was used as a light source.
00 mJ/m2 exposure. The thus exposed plate was developed using an automatic developing machine shown in FIG.

Processing was carried out under the same conditions as in Example 1, except that 30 liters of a 6-fold diluted developer "SDR-1" with water was charged into the developing tank 9 of the automatic processor shown in FIG. First, a plate type discrimination sensor 6 and a plate detection sensor 7 are installed in the insertion section of the automatic developing machine, and these sensors detect the PS of the plate.
It is detected whether it is a printing plate or a photosensitive lithographic printing plate that does not require dampening water, and the conveying drive device 19 connected to the control device 17 is actuated based on this signal. This drive device 19
is the conveyance speed of the plate, when the PS plate signal is detected in advance, the conveyance speed of the PS plate, and when the signal of the dampening water-free photosensitive lithographic printing plate is detected, the dampening water-free photosensitive Each is automatically set to match the transport speed of the lithographic printing plate.

Specifically, in the case of a PS plate, the transport speed was set to 180 cm/min, and in the case of a photosensitive lithographic printing plate that did not require dampening water, the transport speed was set to 60 cm/min. . The brush roller 31 used for development has a diameter of 80 mm, and the material of the brush bristles is nylon 6.12.
Three channel-type brushes were used, each having a bristle thickness of 0.24 mm and a bristle length of 16 mm. The rotation direction is the first
The brush and the second brush were rotated in the forward direction, and the third brush was rotated in the reverse direction.

The peripheral speed of the brush rotation was 60 m/min both when processing the PS plate and when processing the photosensitive planographic printing plate. Here, the developer replenisher is supplied by diluting the stock solution of "SDR-1R" developer replenisher for positive PS plates manufactured by Konica Corp. four times with dilution water. The replenishment amount of developer replenisher is 50ml/m2 for both PS plate and photosensitive lithographic printing plate that does not require dampening water.
And so. Furthermore, the shower refill amount is 500ml/
hr, and the daily replenishment amount was 50 ml/hr.

When a large number of positive PS plates and photosensitive lithographic printing plates that do not require dampening water were processed in succession using an automatic developing machine with the conditions set as described above, both plates were developed without excess or deficiency. A good plate was obtained. In addition, since the plate to be processed is automatically detected by the plate type discrimination sensor, the operator can work without worrying about the plate type, and work efficiency is further improved by preventing erroneous processing.

[0067]

[Effects of the Invention] According to the present invention, the transport speed of the plate during development is set to match each plate type, or the peripheral speed of rotation of the developing brush roller during development is driven to match each plate type. By setting it to do so, both PS plates and photosensitive lithographic printing plates that do not require dampening water can be successfully developed with one automatic developing machine, and the cost is low because the equipment is not large-scale. It has an excellent effect of being able to develop photosensitive planographic printing plates.

Furthermore, the present invention uses a method of automatically changing the rotational peripheral speed of the developing brush roller based on the signal obtained from the plate type discrimination sensor, which facilitates control of the automatic developing machine and provides a photosensitive material with excellent development stability. Development processing of a lithographic printing plate is obtained. Furthermore, the present invention uses a method of automatically changing the conveying speed of the plate based on the signal obtained from the plate type discrimination sensor.
A photosensitive lithographic printing plate is developed which is easy to control using an automatic developing machine, has excellent development stability, and improves work efficiency.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an automatic developing machine equipped with a plate type discrimination sensor used in the method of the present invention.

FIG. 2 is a partial sectional view showing an automatic developing machine equipped with a plate type discrimination sensor used in the method of the present invention.

[Explanation of symbols]

1 PS plate or dampening water-free photosensitive lithographic printing plate 2
Roller 4 Molton roll 6 Plate type discrimination sensor 7 Plate detection sensor 8 Current plate 9 Developing tanks 10, 12 Washing tank 11 Dyeing tank 13 Dilution water 14 Developer replenisher 15 Filter 16 Pump 17 Control device 18 Brush drive device 19 Conveyance drive device 31 Developing brush roller 32 Washing brush roller

Claims (5)

[Claims] 1. A method for developing both a PS plate and a dampening water-free photosensitive lithographic printing plate using an automatic developing machine having at least one developing brush roller, wherein the dampening water-free photosensitive lithographic printing plate is A photosensitive lithographic printing plate characterized in that the peripheral speed of rotation of the developing brush roller when developing the plate is higher than the peripheral speed of rotation of the developing brush roller when developing the PS plate. Development processing method. [Claim 2] A plate type discrimination sensor for discriminating either the PS plate according to claim 1 or the photosensitive lithographic printing plate that does not require dampening water is provided at an appropriate location before development to detect the plate type and automatically A method for developing a photosensitive lithographic printing plate, characterized by changing the rotational peripheral speed of a developing brush roller. Claim 3: In a method of developing both a PS plate and a photosensitive lithographic printing plate that does not require dampening water using one automatic developing machine, the transport speed and dampening water during development processing of the PS plate are 1. A method for developing a photosensitive lithographic printing plate, characterized in that the development process is carried out by changing the conveyance speed during the development process of the unnecessary photosensitive lithographic printing plate. 4. The transport speed during the development process of the PS plate according to claim 3 is 1 of the transport speed of the photosensitive lithographic printing plate that does not require dampening water.
1. A method for developing a photosensitive lithographic printing plate, characterized in that the development process is in the range of /6 to 4/6. 5. Either the PS plate or the photosensitive lithographic printing plate that does not require dampening water according to claim 3 or 4 is provided with a plate type discrimination sensor at an appropriate location before the development process to detect the plate type. A method for developing a photosensitive lithographic printing plate, characterized by automatically changing the conveyance speed.