JPS6380259A - Method for processing photosensitive lithographic plate improved in development stability and the like - Google Patents

Abstract

PURPOSE:To improve instability of development due to change of activity by mixing a concentrated developing solution with a diluent water in a prescribed ratio immediately before use without using a mixing vessel, supplying it on a photosensitive lithographic plate to develop it. CONSTITUTION:The photosensitive lithographic plate (PS plate) 7 is automatically conveyed into an automatic developing machine and developed by mixing both of the concentrated developing solution 1 and the diluent water 2 in a prescribed mixing ratio without using a mixing vessel immediately before use and feeding it onto the photosensitive lithographic plate. The solution 1 and the water 2 are stored in each vessel, respectively, and a mixer 5 for mixing both liquids, and a developing solution feeding member 6 are connected with each other, and pumps 3, 4 are operated in accordance with the conveyance of the plate 7, thus permitting change of activity of the developing solution due to absorption of CO2 in the air to be reduced by separately storing both liquids until the use, and stability of the development processing to be improved.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for developing a photosensitive lithographic printing plate (hereinafter referred to as 28th plate) using an automatic developing machine.
This invention relates to an improvement in the process of producing a developer to be supplied to the 28th plate from a concentrated developer and dilution water.

[Conventional technology]

Conventionally, when developing 28 plates using an automatic developing machine,
The liquid for both images A and A is prepared by adding a concentrated developer and water to a mixing tank at a certain ratio before 8 minutes, stirring to make a liquid with a uniform composition, It is supplied onto 28 plates from the mixing tank.

However, in this method, since the developer is stored in the working solution, its activity is more likely to change due to the absorption of carbon dioxide in the air than in the case of storing it in a concentrated FL solution, making development unstable. It is difficult to manage the development processing work, and it is necessary to install a mixing tank or a used solution storage tank outside the receiving inspection to store the a-shrinking developer and dilution water inside or outside the automatic developing machine, which takes up a lot of space. There is.

[Purpose of the invention]

The first object of the present invention is to provide a means for improving the instability of development due to changes in the activity of the developer in a method of developing the 28th plate using an automatic processor,
The second object is to provide a means for simplifying and reducing costs of the developer-related equipment of the automatic processor used in the method.

[Structure of the invention]

An object of the present invention is to provide a development processing method in which a photosensitive lithographic printing plate is automatically conveyed and developed using an automatic developing machine, in which a concentrated developer and dilution water are prepared, and the process is carried out immediately before use without using a mixing tank. This is achieved by a method for developing a photosensitive lithographic printing plate, which comprises mixing the two at a certain ratio and then supplying the mixture onto the photosensitive lithographic printing plate for development.

In the present invention, the developing solution (working solution) to be supplied onto the plate surface of the 28 plate to be processed is prepared by mixing the concentrated developing solution and dilution water at the time of supply.

It is preferable to store the concentrated developer solution and the dilution water separately, and it is also preferable to mix the two solutions at a constant ratio using one pump for each solution.

In the present invention, the concentrated developer and dilution water are mixed to form a solution with a uniform composition, but the developer is supplied to the 28th plate without stirring in a mixing tank. Provide uniform mixing means in the middle of the piping.

Specifically, for example, a concentrated developer and dilution water are each placed in a tank provided inside or outside the automatic processor, and these tanks and a liquid mixing mixer are connected to each other, and the mixer and the automatic processor are used to process 28 plates. A developer supplying member for supplying a developer to the developer is connected by piping, and a pump for conveying concentrated developer to the mixer and a pump for conveying dilution water to the mixer are provided between each of the above and the mixer. These pumps may be operated in conjunction with the transport.

It is also possible to directly lead dilution water to the mixer from a water supply pipe or the like without providing a tank for dilution water.

As the above-mentioned mixing means, mixers such as an Orice type, a packed type, a puffful type, a 70-F impeller type, a split type (static mixer), a trap sphere type, and a compound sphere type can be preferably used, but they are particularly suitable. The two types are the trap sphere type and the split type.

Concentrated developer has a high specific gravity of 1.2 to 1.4, and when mixed with water, there is a large difference in specific gravity, so it is desirable to have a turbulent flow inside the mixer.
It is preferable that there is a change in diameter and that there is a vortex.

The above pumps include bellows pump, tube pump,
A gear pump or the like can be used, but a tube pump is preferred.

Next, a malfunction of an automatic mixing machine used for carrying out the method of the present invention is shown in Fig. fjS1 (approximate side sectional view), and an example of the mixer is shown in Figs. figure)
Shown below.

In FIG. 1, 1 is a concentrated developer tank, and 2 is a diluted water tank. The concentrated developer and diluted water contained in these two tanks are each sent to a mixer 5 by a metering pump 3.4, where they are mixed. The two are mixed to form a developer solution M, which is sent to the developer supply member 6.
The two X's in Figure 6 supplied to the 28th plate 7 are connected by piping. The operation of the metering pump 3.4 can be controlled by, for example, a sensor provided at the bottom of the insertion table 8, which detects whether or not the 28th plate is being conveyed, its width, etc.

Fig. fi2 is a schematic side sectional view showing an example of the above mixer, where A is an orifice type, the mouth is a filling type, C is a baffle type, 4 is a float impeller type, 5 is a split type (static mixer), and 6 is a trap. 7 indicates a spherical shape, and 7 indicates a coupled spherical shape. The arrows in the figure schematically indicate the flow of the liquid.

In the present invention, in order to keep the temperature of the developer supplied on the 28th plate constant rI4W1, the temperature 'l! The 4WI device is installed at an appropriate location, for example, at any location on the piping connecting the mixer 5 and the developer supply member 6 (preferably at a location near the developer supply member), or in the concentrated developer tank and the diluted water tank. However, the former is preferable. When the concentration ratio is high (for example, 5 times or more), a method of keeping only the dilution water at a constant temperature is also useful in terms of equipment cost.

As a temperature regulator, in addition to one having a heating member and a cooling member, one having only a heating member is particularly preferably used from the viewpoint of device cost and space. Preferably, the temperature regulator further has a mechanism for adjusting the heating intensity depending on the room temperature.

In the present invention, there is no restriction on the means for supplying the developer onto the plate 28, and any means can be used. For example, a method of spraying, spraying or dropping the liquid onto the plate using a shower pipe or nozzle, or A method may be used in which the developer is supplied from a developer supplying member placed in contact with or in a non-contact position so as to coat the plate surface with the developer. The method of bringing the developer supplying member into contact with the 28th plate and supplying the developer onto the 28th plate includes, for example, a method of supplying the developer by rubbing the 28th plate with a water-absorbent member such as a sponge or cloth, or a method of supplying the developer by rubbing the 28th plate with a water-absorbing member such as a sponge or cloth, or a method using a rubber or the like. Regardless of whether it is a non-water-absorbent material or a water-absorbent material such as the sponge or cloth, there are methods such as forming these materials into a roller shape and feeding the material while synchronizing the rotation of the roller with the transported 28 plate. It will be done.

Furthermore, methods for supplying the developer onto the 28th plate without contact between the developer supply member and the 28th plate include, for example, a method in which the developer is stored in a narrow gap and supplied by passing the 28th plate through the gap; There is a method of supplying the 28 plate by bringing it into contact with the developer which hangs down in a rod shape due to surface tension from the liquid supply member, or by storing the developer in a cylindrical object and placing a narrow gap on the side of the cylindrical object. Examples include a method of supplying the material by making a 28-plate and passing a 28-plate through the gap.

Furthermore, in these developer supply methods, the developer can be supplied onto the 28 plate not only in liquid form but also in foam form. Furthermore, in the method of supplying the developer by spraying, the developer can also be supplied in the form of a mist.

Other methods of supplying the developer include a method of applying the developer to a film base and laminating it onto the 28 plate, and a method of supplying a wax-like developer by bringing it into contact with the 28 plate. It will be done.

Further, as the developer supply method, only one method may be used, or two or more methods may be used in combination.

In the present invention, the amount of developer supplied onto the printing plate by these methods is preferably in the range of about 10,100 O or less per 1 28 plate, and more preferably 500 O per 1+++''.
A range below 1 is preferably used.

Further, the amount of developer supplied can be varied depending on the area and type of the 28 plate, the area ratio of non-images, the width and length of the plate, etc. The temperature of the developer when supplied to the 28th plate is 10
℃ to 60℃ is suitable, preferably 20℃ to 45℃
It is ℃.

In addition, the metering pump that sends the developer to the developer supply member has
It is desirable that a control Wi mechanism linked to a detection mechanism such as a sensor for detecting the presence or absence of the 28th plate is attached, and a stop mechanism is activated before the 28th plate is carried into the developing section and after it passes through.

The automatic developing machine used to carry out the method of the present invention is one that automatically transports and processes the 28th plate, and is preferably a mixer that mixes a concentrated developer and diluted water, and preferably a developer supplied to the 28th plate. The shape, configuration, structure, etc. of the device are not particularly limited as long as it is equipped with a means to adjust the temperature of the developer to be constant and a means to supply an appropriate amount of developer. A horizontal conveyance type using a belt or the like is preferred.

The 28th plate used in the method of the present invention is one in which a photosensitive composition is coated on a support, or a soluble layer on which an image-like resist layer can be formed by an electrophotographic method or the like is provided on a support. It is something that

Supports used in the above 28 editions include paper, plastic (e.g. polyethylene, polypropylene, polystyrene, etc.) laminated paper, aluminum (including aluminum alloys), metal plates such as zinc, copper, etc., cellulose diacetate. , films of plastics such as cellulose triacetate, cellulose propionate, polyethylene terephthalate, polyethylene, polypropylene, polycarbonate, poly and nylacetal, etc., paper or plastic films laminated or vapor-deposited with metals such as those mentioned above, aluminum or chrome plated. Among these, aluminum and aluminum-coated composite supports are particularly preferred.

In addition, the surface of the aluminum material improves water retention and is connected to the photosensitive layer. It is desirable that the surface be roughened for the purpose of improving adhesion.

The 28th edition photosensitive composition used in the present invention contains a photosensitive substance as an essential component, and the physical and chemical properties of the photosensitive substance change upon exposure or subsequent development treatment. For example, the solubility in the developing solution differs due to exposure, the adhesion between molecules differs before and after exposure, and the affinity for water and oil differs due to exposure or subsequent development processing. can.

Typical photosensitive substances include, for example, photosensitive diazo compounds, photosensitive 7dide compounds, compounds with ethylenically unsaturated double bonds, boxy compounds that polymerize with acid catalysts, and C-O compounds that decompose with acids. Examples include compounds having a -C- group. Examples of photosensitive diazo compounds include 0-quinonenoanodo compounds, which are positive-type compounds that become alkali-soluble when exposed to light, and aromatic diazonium salts, which are negative-type compounds whose solubility decreases when exposed to light.

The developer used in the present invention contains an alkali agent, an organic solvent, an anionic surfactant, a sulfite, etc., and water as a solvent for a negative PS plate using a photosensitive substance such as a diazo compound. On the other hand, for a positive type 28 plate having a photosensitive layer containing an 0-quinonenoanodo compound, the alkaline agent is usually 0.1 to 30% by weight, preferably 0.
．． Water tS solution containing 5-20% by weight (usually pH 9-14)
range) is included.

〔Example〕

Specific examples of the present invention are shown below.

Example 1 28 plates were developed using the automatic developing machine shown in FIG.

Using the mixer shown in Figure 2 (Fine Mark Trap Ball 25D (55m/-') Manpo Shoten),
The concentrated developing tank 1 in the figure is made of vinyl chloride with a capacity of 31, and the dilution water tank 2 has a capacity of 151.
A material made of vinyl chloride was used.

At the bottom of the insertion table 8, optical sensors for detecting the 28th plate are arranged side by side in the widthwise direction, and the signals detected by these actuate the metering pump 3.4.
It was controlled so that the appropriate amount was sent as it passed through the bottom of the tube.

In FIG. 1, 9 is a pair of transport rollers, 10 is a developer tank,
11 is an idle roller, 12 is a brush roller, and 13 is a squeeze roller.

The developer supply member 6 is made up of two plate materials, and the two
It has a slit formed by the plate material at the lower end. As a cross plate material, the upper (outlet side) plate material has a thickness of 75 μ and a length (horizontal direction perpendicular to the conveyance direction) of 900 Ill If
i, width (in projection on the horizontal plane) 50 + a m, thickness 175 μm 1 length 900 m on the lower (inlet side) plate material
mm, width (in projection on the horizontal plane) 55 +o I
No. 6 rectangular sheets of polyethylene terephthalate were used, and the slit gap was made to increase or decrease depending on the amount of developer supplied. The lower end of the developer supply member 6 is provided with an inclined plate 14.
When the 28th plate is not passing through the upper surface, a developer reservoir is formed in the four parts formed by the lower end of the developer supplying member 6 and the inclined plate 14, and the tip of the 28th plate is connected to the developer supplying member. A pair of transport rollers 9 and a presser roller 18 were provided so as to enter the contact portion between the lower end of the roller 6 and the inclined plate 14.

A developer having the same composition as the developer supplied from the developer supply member 14 is put into the developer tank 10, and the temperature of this developer is maintained at 25° C., and the development wL'! The developer in a10 was not replenished with any developer other than that brought in by the 28th plate. The total development time was 20 seconds.

The 28th edition is SMP-N (product name, Bo type 28th edition, Konishiroku Photo Industry Co., Ltd.!!!) No1003X 800n++a
A concentrated developer having the following composition was used.

<Developer composition> Potassium silicate 40 parts by weight KOH
9 parts by weight Polyoxyethylene lauryl ether sodium sulfonate (trade name: ^0 Air 20c) 0.02 parts by weight Water
50fflff 1 part (undiluted solution): 4 (water) is sent to the mixer at a ratio of e-condensed water: 4 parts dilution water, mixed, and the developer ( The working temperature was kept at 25°C.

The amount of developer supplied is Q160+of for the first PS plate,
As a result of continuously processing 100 plates, plate-making performance equivalent to that of the current holding solution homogenized in a mixing tank was obtained, and among the obtained plates,
As a result of offset printing the 1st edition and the 100th edition, good printed matter was obtained.

Comparative Example 1 The same experiment as in Example 1 was conducted except for the following changes regarding the inlet.

(a) As an automatic developing machine, an automatic developing machine shown in Fig. 3 was used, in which a mixing tank was used instead of a mixer. The mixing tank has a capacity i
A layer made of 3N vinyl chloride was used, and the amount of developer in the layer was replenished from a concentrated developer tank and a dilution water tank so that the amount of developer in the layer was maintained at 2.51±0.31.

The metering pump 16 was operated in response to a signal detected by the optical sensor, and the developer was sent from the mixing tank 15 to the developer supply member.

In addition, in FIG. 3, 17 is a pump for stirring the liquid in the mixing WJ 15.

As a result, as is clear from Table 191, there is no difference in the performance of the developing solution over time between the mixer and the mixing tank when used immediately after dilution. But 1st and 3rd
The mixing tank may be stored in a diluted state (Saturdays, Sundays, holidays, etc.), resulting in clear sensitivity and 1)
In both cases, the influence of carbon dioxide absorption appears and the liquid deteriorates. In the case of a mixer, constant performance can always be obtained because there is no storage of the liquid used.

〔Effect of the invention〕

The present invention provides a method for developing the 28th plate using an automatic developing machine, in which the developer to be supplied to the 28th plate is separated into a concentrated solution and dilution water before the supply, and both liquids are mixed. The state? ! ! Since the developer is not stored as a working solution, changes in the activity of the developer due to carbon dioxide absorption in the air are reduced, and the stability of the development process is improved.

In addition, the method of the present invention allows the mixing tank or developing solution storage tank associated with conventional automatic processors to be replaced with a relatively small and inexpensive mixing wave! By replacing Wl in the mixer (mixer), it is possible to simplify the developer-related equipment of the automatic processor and reduce costs. Note that if the dilution water is directly led to the mixer from the water supply or the like, the equipment required for storing the dilution water can be simplified.

[Brief explanation of the drawing]

1 and 2 are cross-sectional views of examples of an automatic developing machine and its mixer used in the present invention, respectively. 1... Concentrated developer tank 2... Dilution water tank 3.4.16... Metering pump 5... Mixer G... Developer supply member 7
... PS plate 8 ... Insertion table 9 ... Transport roll pair 10 ... Developer tank 11 ... Id roller 12 ... Brush roller 13 ... Squeeze roller 14 ... Inclined plate 15 ...Mixing tank 17.
... Pump 18... Presser roller! ... Concentrated liquid tank 2 ... Dilution water tank 3.4 Metering pump 5 ... Mixer 6 ... Current shell liquid supply member No. Figure 2 A
donkey
2nd 3rd figure 15...Mixing tank 16...
Metering pump Figure 4

Claims (1)

[Claims] In a development processing method in which a photosensitive lithographic printing plate is automatically conveyed and developed using an automatic developing machine, a concentrated developer and dilution water are prepared, and both are mixed in a fixed ratio immediately before use without using a mixing tank. A method for developing a photosensitive lithographic printing plate, which comprises mixing, supplying the mixture onto the photosensitive lithographic printing plate, and performing development.