JPH0418563A - Method and device for developing photosensitive resin plate - Google Patents

Abstract

PURPOSE:To suppress the increasing of scum in a washing liquid deposited at the time of washing by forcibly flowing the washing liquid in a washing tank. CONSTITUTION:The side surface of the washing tank 5 has a supplying port 5 and an ejecting port 7, besides a plate fixing base 1 and a brushing base 2. The position of the supplying port 6 is at the bottom part of the central line of the tank, and the ejecting port 7 is connected to a circulating pump 8 by piping, and main and bypass routes are distributed therefrom by the piping. During a process that an unexposed part is rubbed while being infiltrated into the washing liquid is developed, the washing liquid is forcibly made flow. Therefore, the aggregation and deposition of the rubbed unexposed part is prevented. On the other hand, after solid matter in the washing liquid extracted during or after a developing process is removed, an obtained filtrate can be reused as the washing liquid for developing. Thus, the aggregation and deposition of dispersed resin at the time of the developing are reduced, and the dispersed resin in a developing liquid is removed.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a developing method and a developing device for photosensitive resin plates, and in particular to a flexographic resin plate having rubber elasticity, capable of water-based development, and having excellent ink resistance. The present invention relates to a method and a developing device for developing a photosensitive resin plate useful for printing.

More specifically, during the washing process of photosensitive resin plates, we suppress the aggregation of the photosensitive resin dispersed in the washing liquid inside the device as much as possible, and at the same time remove all the precipitated scum (agglomerated solids such as dispersed resin). The present invention relates to a developing method and a developing device that are designed to capture keyaki.

(Prior art) Printing plates using photosensitive resin are superior in operability, productivity, price, and printing characteristics compared to conventional printing plates, and have rapidly become popular in various printing fields in recent years. There is.

Devices for developing photosensitive resin plates include: ■A device that uses compressed air to blow away unexposed areas to form a relief; ■A device that sprays a washing liquid onto the plate surface at a constant pressure to form a relief; A device has been devised and put into practical use that uses a brush or the like to scrape a printing plate fixed on a flat or cylindrical surface into a washing liquid.

(Intelligence to be Solved by the Invention) When water (tap water) or water added with a surfactant, etc. is used as a washing liquid for developing a photosensitive resin in the developing device as in (2) above, even if the surfactant is Even if it is desired to improve the dispersibility and reduce the cohesiveness of the resin washed out with the agent, the amount of scum that is precipitated in the washing liquid during washing increases,
When the photosensitive resin dispersed in the washing solution reached a high concentration, there was no way to prevent this.

Therefore, if left as is, it will not only adhere to the inside of the developing machine, brushes, etc., but also to the printing plate after development, which poses a serious problem.

(Means for Solving the Problems) In order to improve the current situation, the present invention has developed the following improved developing method and developing device as a result of intensive studies on developing methods and devices for photosensitive resin plates. . That is, the present invention is a method of developing a photosensitive resin plate by immersing it in a washing solution after exposure and scraping out the unexposed areas, by forcibly flowing the washing solution. A method for developing a photosensitive resin plate characterized by preventing agglomeration and precipitation in unexposed areas, and a circulation device having a filter is provided outside a washing liquid tank in a developing device for a photosensitive resin plate. Furthermore, the present inventors focused on the solubility of the photosensitive resin in the washing solution, and developed a method for developing a photosensitive resin plate, in which the solids dispersed in the washing solution after washing out the resin plate. The above problem could be solved by reusing the removed filtrate.

In other words, in the method of developing a photosensitive resin plate by immersing it in a washing solution and scraping out the unexposed areas after exposure,
During the development process, the washing liquid is forced to flow to prevent agglomeration and precipitation of the scraped out unexposed areas,
On the other hand, the photosensitive resin plate is characterized in that after removing solids from the washing liquid extracted during or after the development process, the obtained filtrate is reused as the washing liquid for development. A developing method and a developing device comprising a washing tank, a circulation device, and a resin filtration tank, wherein the circulation device forces the washing liquid in the washing tank to flow, and the resin filtration tank is configured to forcefully flow the washing liquid in the washing tank. A developing device for a photosensitive resin plate is characterized in that solid matter is removed from a washing liquid in a washing tank and provided to the washing tank.

These developing methods and devices can be used even in automatic developing machines in which a circulation device and a resin filtration tank are installed in the washing tank, and each process of washing, rinsing, draining, drying, and post-exposure is made continuous. Fully functional.

The circulation device is configured to forcefully flow the washing liquid in the washing tank, and the resin filtration tank removes solid matter from the washing liquid and supplies it again to the washing tank. The present invention is a developing device for a photosensitive resin plate, characterized in that the developing method and the developing device are used in a washing section of a continuous automatic developing machine.

Examples of photosensitive resin plates used in the present invention include:
Polyamide-based photosensitive resins containing polyamide as an essential component that dissolve or swell in aqueous, alkaline aqueous solution, or alcohol-based cleaning solutions, polyvinyl alcohol-based photosensitive resins containing polyvinyl alcohol as an essential component, and low-molecular-weight unsaturated group-containing polyesters. Examples include polyester photosensitive resins having an essential component, acrylic photosensitive resins having an acrylic low molecular weight polymer as an essential component, and polyurethane photosensitive resins having polyurethane as an essential component.

Photocurable properties are imparted to these photosensitive resins by adding photopolymerizable unsaturated monomers, photosensitizers, and the like.

Recently, photosensitive flexo plates that can be developed in an aqueous washout solution have been proposed from the viewpoint of toxicity and safety. Among these, those containing a copolymer containing a conjugated hydrocarbon and an α,β-ethylenically unsaturated carboxylic acid or its salt as essential components and a monoolefinically unsaturated compound, and a conjugated diene-based carbonized Photosensitive elastomer composition containing a hydrogen polymer or a copolymer of a conjugated diene hydrocarbon and a monoolefinic unsaturated compound, a hydrophilic polymer compound, and a non-gaseous ethylenically unsaturated compound, α, β- Examples include hydrophobic oligomers containing ethylenically unsaturated groups and elastomers containing water-swellable substances. All of these contain photopolymerizable unsaturated monomers, photosensitizers, and others to impart photocurability.

As mentioned above, there are various photosensitive resins that can be used in the present invention, but it is particularly effective for resins that contain hydrophobic polymers and hydrophilic polymers, have strong stickiness, and tend to aggregate in a stationary washing solution. be.

Specifically, hydrophobic polymers such as chlorinated polyethylene have a chlorine content of 50 to 10% by weight and a glass transition temperature (hereinafter referred to as Tg) of 5°C or less, and hydrophilic polymers include amide bonds, urethane bond,
Particularly effective is a photosensitive resin containing a polymer having a butadiene chain and a carboxylic acid or a salt thereof, and having an ethyl/one unsaturated bond at at least one end.

In the present invention, the ultraviolet rays used for curing the photosensitive resin plate have a wavelength of 150 to 500 nm, particularly 30 to 40 nm.
Light in the wavelength range of 0 nm is effective, and the light sources used include low-pressure mercury lamps, high-pressure mercury lamps, carbon arc lamps,
Ultraviolet fluorescent lamps, chemical lamps, xenon lamps, and zirconium lamps are preferable.

Next, in the present invention, the photosensitive resin plate is exposed to an image by exposing it to ultraviolet rays by applying a negative film having a transparent image under the above-mentioned light source, and then removing the unexposed non-image area using a cleaning solution. , a relief image is obtained, while the uncured photosensitive resin that has been melted and removed remains in the washing tank as an emulsion or suspension solution.

The washing liquid has a pH of 5.0, including general household water.
~9.0 water is optimal, and using this water as the main component, alkaline compounds such as sodium hydroxide and sodium carbonate,
It may contain a surfactant, a water-soluble organic solvent, etc., and in order to promote the dispersion of the photosensitive resin in water and maintain the dispersed state, it is particularly preferable to include a surfactant. The above surfactants include sodium alkylnaphthalene sulfonate,
Sodium alkylhenzenesulfonate is most suitable; in addition, anionic surfactants containing carboxylic acid salts, sulfuric acid ester salts, sulfonate salts, phosphoric acid ester salts, polyethylene glycol chain-containing substances, polyhydric alcohols, etc. derivatives, nonionic surfactants such as sorbitan derivatives,
- Cationic surfactants containing tertiary amine salts, quaternary ammonium salts, etc., and amphoteric surfactants containing amino acid type and hetain type hydrophilic groups can be used.

The washing solution should be heated at 25°C to 50°C, especially at 35°C to 4
Preferably, it is used at 5°C.

The method of the present invention is characterized by forcibly flowing the washing liquid to suppress aggregation of the photosensitive resin dispersed in the washing liquid as much as possible, but the flow rate is 10 cm/
sec or more, preferably 5Qcm/sec or more, and even 100
The speed is c+n/sec or more, and the faster the better, but it is preferably about 300 cm/sec or less in relation to the capacity of the pump. In addition, as a method of forced flow, there is a method in which the washing liquid is circulated and stirred by an external circulation pump through the water supply and drainage port of the washing tank of the main body, or in addition to this method, ■ circulating water is flowed over the horse face or side of the washing tank of the main body. A method of installing a generation fan and stirring the washing liquid. ■A method in which a stirring function is attached to the cleaning brush submerged in the cleaning liquid in the main body cleaning tank, and the cleaning liquid is constantly stirred while the brush plate is operating. ■A method in which the cleaning liquid is sprayed out from between the brushes of the cleaning brush plate submerged in the cleaning liquid in the cleaning tank of the main body using an external circulation pump and stirred.

etc.

Next, the method and apparatus of the present invention will be specifically explained using the drawings.

1 to 4 show an embodiment of the developing device of the present invention. Figure 1 shows a flat plate type developing device, in which a plate fixing table 1 for a photosensitive resin plate is flat plate type, and a brush table 2 is placed in contact with it.
is installed. Figure 2 shows a rotary type developing device.
A rotary plate fixing table 3 and a brush table 4 along the white plate.
is installed. In Fig. 1.2, in addition to the plate fixing table 1.3 and the brush table 2.4, there is provided one supply port 6 or 15 and one discharge lower or 16 on the side of the washing tank 5 or 14, and the supply port 6 Alternatively, the position 15 is located at the lowest part of the fire line in the tank, and the drainage lower or 16 is located about 31 below the washing liquid level above the fire line in the tank.

The discharge lower or 16 is connected to the circulation pump 8 or 17 by piping.
It is connected to the main route from there by piping,
distributed to bypass routes.

The bypass route is equipped with a cartridge filter 9 or 1, and the flow rate is intentionally controlled with a valve to catch all the scum that tries to pass through. A pressure gauge 10 or 19 is installed in front of the cartridge filter 9 or 18, so that the pressure increase due to clogging of the filter element can be constantly observed. The flow meter 11 or 20 is installed at a position where both the total flow rate of the circulation pump and the flow rate of the cartridge filter installation bypass route can be observed.

The flow path of the circulating eluate is controlled by a three-way socket 12 or 21 and a two-way socket 13 or 22.

Precipitated scum in the washout fluid is captured by the device of the invention as follows.

The scum-containing washing liquid whose aggregation has been suppressed as much as possible by the circulation pump passes through the circulation pump 8 or 17 from the drainage lower or 16, and is divided into the main route or a bypass route where the cartridge filter 9 or 18 is installed. The bypass route is adjusted in advance to a desired flow rate using a two-way filter, and most of the scum in the washing liquid is captured when it passes through the cartridge filter 9 or 18.

The eluate is divided into the bypass route and the main route.
It joins again and returns to the circulation pump total displacement, and the supply port 6 or 1
5 and returns to the washing tank 5 or 14.

As for the type of element used in the cartridge filter, a wind cartridge structure is most preferable in terms of scum trapping performance, operability, durability, etc. Although the circulation pump may be a pump with a constant displacement, it is preferable to control the circulation rate with a variable displacement pump or an inverter-controlled pump, which enables filtration and trapping in accordance with the amount of plate washing and the state of scum generation.

FIG. 3 is a schematic cross-sectional view of an embodiment of the apparatus of the present invention, including a washing tank 23, a circulation filtration device 24, and a resin filtration device 25.
, a washing liquid storage tank 26, and the flow of the washing liquid is indicated by an arrow.

In Fig. 3, a rotary type plate fixing table 2 in the washing liquid is shown.
The exposed photosensitive resin plate 28 attached to 7 is rubbed by a brush 29, and the resin in the unexposed area is dispersed in the washing liquid.

FIG. 4 is a schematic sectional view of an automatic developing machine in which the steps of washing, rinsing, draining, drying, and post-exposure are made continuous, and a washing part, a circulation device, and a resin filtration tank are integrated.

In FIG. 4, the exposed photosensitive resin plate attached to the conveyor table 35 is automatically conveyed to the washing tank 37, and the plate 3
6, and the resin in the unexposed areas is dispersed in the washing liquid. During the development process, the washing liquid is supplied to the circulation pump 30.
Alternatively, the cartridge filter 38 is sent to a cartridge filter 33 or 39 to remove scum generated during development. Thereafter, the washing liquid is supplied to the washing tank 23 or 37 again, thereby causing the washing liquid in the washing tank to flow. On the other hand, during or after the development process, the washing liquid extracted from the bottom of the washing tank is transferred to the coagulation and sedimentation tank 32 or 40 in the resin filtration device 25, and is then statically removed. By doing so, the dispersed resin in the washing liquid is coagulated and precipitated. The precipitated resin is filter medium 33 or 4.
1, and the filtrate is collected in the filtrate storage tank 34 or 42. The filtrate can be reused either directly or with a new washout solution added thereto and transferred to the washout tank directly or via the washout tank 26 before development.

In addition, in the continuous automatic developing machine shown in FIG.
After each step of water rinsing 44 and draining 45, drying 46 and post-exposure 47 for a desired time, the printing plate is completed.

In the present invention, 30 minutes or more is sufficient for allowing the washing liquid to stand still and coagulating and precipitating the resin in the resin filtration device, but the agglomeration rate, filtration rate,
From the viewpoint of workability, developer exchange cycle, etc., it is preferable to leave it standing for 6 hours or more. The filter medium is not particularly limited as long as it can filter the resin, but examples include filter paper, sheet-like structures made of natural fibers such as cotton or synthetic fibers, general-purpose cartridge filters, household draining materials, wire mesh, etc. I can do it.

(Function) By employing the method of the present invention, the washing liquid is constantly circulated, and the water flow dispersion force (diffusing force) generated thereby suppresses agglomeration and precipitation in the unexposed area as much as possible, and more preferably suppresses the surfactant. By blending them, a synergistic effect is exerted on the dispersion power, and the agglomeration and precipitation of scum is significantly reduced.

On the other hand, during or after the phenomenon process, by taking advantage of the tendency of photosensitive resin to coagulate and precipitate, solids can be precipitated and removed simply by extracting the washing liquid from the washing tank and allowing it to stand still. The filtrate can then be used again as a developer.

(Examples) The present invention will be specifically explained below with reference to Examples, but the present invention is not limited to these Examples.

The cartridge filter element used in the present invention is ADVANTEC TCW-75or100PP.
The filter medium in the resin filtration device was manufactured by Dasbon Hakumoto.

Examples 1 to 4 21.8 parts of hexamethylene diisocyanate, 15.4 parts of dimethylolpropionic acid, polytetramethylene glycol (PG-100 manufactured by Nippon Polyurethane Industry ■) 7.
A solution of 6 parts of di-n-butyltin dilaurate and 1.0 parts of di-n-butyltin dilaurate dissolved in 300 parts of tetrahydrofuran was placed in a 12 flask equipped with a stirrer, and the flask was heated to 65 °C while stirring to continue the reaction for 3 hours. Ta. In a separate container, acrylonitrile-butadiene oligomer containing terminal amino groups (HycarATBNBNX1300
A solution prepared by dissolving 55.3 parts (manufactured by Ube Industries, Ltd.) in 100 parts of methyl ethyl ketone was added to the above IIV flask at room temperature with stirring. The obtained polymer solution was dried under reduced pressure to remove tetrahydrofuran and methyl ethyl ketone to obtain a polymer having a number average molecular weight of 21,000. Next, 4.5 parts of lithium hydroxide was added to a solution of 100 parts of the polymer dissolved in 100 parts of methyl ethyl ketone.
A solution prepared by dissolving 8 parts in 100 parts of methyl alcohol was added with stirring at room temperature, and the mixture was further stirred for 30 minutes to obtain hydrophilic polymer (I).

The above hydrophilic polymer [1] 11.0 parts As a hydrophobic polymer, 45 parts of chlorinated polyethylene (H-135 manufactured by Osaka Soda ■), styrene-butadiene rubber (SRR1507)
Nippon Synthetic Rubber ■) 15 parts, butane oligoacrylate (PB-^ Kyoeisha Yushi Co., Ltd.) 285 parts, Hensyl dimethyl ketanol (Irgacure 651, Chiha Geigy ■) 1 part, and hydroquinone monomethyl ether 0
．． 5 parts were dissolved in 40 parts of toluene and 10 parts of water, dispersed, kneaded, defoamed, and then molded to create a photosensitive resin plate.

After imagewise exposure of the resulting water-developable photosensitive resin plate, the first
Using the developing device shown in Fig. 2, the surfactant used as a washing liquid was water containing 4% by weight of sodium alkylnaphthalene sulfonate (Perex NB-L ■ manufactured by Kao) 50-7.
While the photosensitive resin plate was immersed in 0f, the unexposed areas were scraped out and developed while being circulated and filtered. As a result, 3-5
kg of unexposed resin was eluted into the washing solution, but since the solution was constantly stirred by a circulation pump, there was no amount of scum attached, and a printing plate faithful to the image was obtained without any defects or stains.

Comparative Example 1.2 In Example 1, the Cartrinon filter was not used,
Furthermore, the photosensitive resin plate was developed in the same manner as in Example 1 except that the circulation pump was not used.

As a result, a large amount of scum, which caused defects in the image, adhered to the plate, making it completely unusable as a printing plate.

Table 1 shows the amount of resin eluted, the amount of circulation, and the amount of scum attached to the plate.

Table 1 Example 5.6 Using the developing device shown in Figure 3, Example 1 was used as the washing liquid.
The photosensitive resin plate was immersed in the same surfactant-containing water 70f as in Step 4, and the drainage rate of the circulation pump was set to 801/min or 4.
0! As a result of performing each development while circulating at 1/min, approximately 5 kg of resin in the unexposed area was dispersed in the washing solution.

Transfer the washing liquid to a resin filtration device and leave it standing for 8 hours,
The flocculated and precipitated resin was filtered. The filtrate was stored in a washing liquid storage tank to ensure that the resin was not coagulated and precipitated. Next, the filtrate was transferred to a developing machine, and the Miyako resin plate was developed in the same manner as described above, and as a result, development was performed at the same development speed as the -th time.

After that, the same operation was repeated 20 times, but the development speed did not change.

Note that Table 2 shows the respective development speeds and amount of plate adhesion.

Example 7.8 Development was carried out in the same manner as in Example 1.2 except that epichlorohydrin rubber (manufactured by Ebichroma-H Daiso) was used instead of the chlorinated polyethylene in Example 5.6, and the results are shown in Table 1. As in Example 5.6, in both cases, there was a decrease in the development speed and adhesion of the dispersed resin to the relief (
No scum formation was observed.

Example 9.10 All procedures were carried out in the same manner as in Example 5.6, except that styrene-butadiene-styrene fluorocarbon copolymer (Craton 1101 manufactured by Schil Petrochemical Co., Ltd.) was used instead of chlorinated polyethylene in Example 5.6. As shown in Table 2, as in Example 5.6, no decrease in development speed and no adhesion of the dispersed resin to the relief (scum formation) were observed.

Table 2 Example 11 Using the continuous automatic developing machine shown in FIG. 4, the photosensitive resin plate was immersed in 70β of the same surfactant-containing water as in Examples 1 to 10 as a washing liquid, The displacement of the circulation pump is 7
Development was carried out with controlled circulation at 0 to 80 r/min, and the solution after washing, in which the resin in the unexposed areas of about 5 parts per day was dispersed in the washing solution, was treated in the same manner as in Example 5.6. It was then filtered and regenerated and used repeatedly. All of the reliefs after washing were subjected to the post-washing processes, ie, rinsing, drying, and post-exposure, to obtain a printing plate.

As a result, I made plates for 20 consecutive days and produced a printing plate.
The development speed was constant, and there was no scum attached to the printing plate.

(Effects of the Invention) As described above, by employing the method and apparatus of the present invention having such a configuration, aggregation and precipitation of the dispersed resin during development are reduced as much as possible, and the resin dispersed in the developer is removed. There are almost no concerns about defects or stains caused by adhesion of the dispersed resin to the plate or device. Furthermore, since the washing liquid can be reused, it is possible to greatly improve workability and cost, and it is also non-polluting and greatly contributes to environmental conservation.

[Brief explanation of the drawing]

1 to 4 are examples of an embodiment of the developing device of the present invention,
Fig. 1 is a perspective view of a flat plate type developing device, Fig. 2 is a perspective view of a rotary type developing device, and No. 37 is a washing tank, a circulation device,
It is a schematic sectional view of a resin filtration tank. FIG. 4 is a schematic cross-sectional view of a continuous automatic developing machine. In Figures 1 to 4, 1.3.27: Plate fixing table 2.4.29.36: Brush stand 5.14.23.37: Washing tank 6.15: Supply port A, 16 + discharge port 8.17 .30.38: Circulation pump 9.1B, 31.39: Cart nozzle filter 35:
Plate continuous conveyance platform 3rd

Claims (4)

[Claims] (1) In a method of developing a photosensitive resin plate by immersing it in a washing liquid after exposure and scraping out the unexposed areas, the unexposed areas are scraped out by forcing the washing liquid to flow. A method for developing a photosensitive resin plate, characterized by preventing agglomeration and precipitation of parts. (2) In a method of developing a photosensitive resin plate by scraping out the unexposed area while immersing it in a washing solution after exposure, during the development step, the washing solution is forced to flow. On the other hand, after removing solids from the washout solution extracted during or after the development process, the obtained filtrate is recycled as a washout solution for development. A method for developing a photosensitive resin plate, characterized in that it is used. (3) A developing device for a photosensitive resin plate, characterized in that a circulation device having a filter is provided outside the washing liquid tank in the developing device for a photosensitive resin plate. (4) A developing device comprising a washing tank, a circulation device, and a resin filtration tank, wherein the circulation device forces the washing liquid in the washing tank to flow, and the resin filtration tank is configured to forcefully flow the washing liquid in the washing tank. 1. A developing device for a photosensitive resin plate, characterized in that solid matter is removed from a washing liquid in a washing tank and provided to the washing tank.