JP2007122075A - Method and apparatus for developing photosensitive resin relief printing plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a developing method for a photosensitive resin printing plate which can reduce the cost for treating a waste liquid by using an aqueous developing liquid not containing a surfactant and recycling and reusing the developing liquid. <P>SOLUTION: A photosensitive resin printing plate which is hardened in a prescribed pattern by exposure is developed by spraying an aqueous developing liquid comprising only water or two phases of gas and liquid by mixing the gas, to a surface of a printing plate under a high pressure (water pressure of 1 to 30 MPa, gas pressure of not lower than 0.1 MPa); a hydrophobic photosensitive resin mixed in a used developing liquid is separated and removed by means of filtration or the like; and the filtrate is recycled and reused as a developing liquid. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention is a method for developing a photosensitive resin relief plate comprising a step of spraying an aqueous developer at 40 ° C. or higher to a photosensitive resin relief plate after exposure at a pressure of 1 MPa to 30 MPa, wherein the aqueous developer comprises The present invention relates to a method for developing a photosensitive resin relief printing plate, which contains a photosensitive hydrogen abstraction agent and has a surfactant content of 0.5 wt% or less in the aqueous developer.

Conventionally, a photosensitive resin plate has been used as a printing plate material for relief printing represented by cardboard printing, film printing, preprint printing, and label printing.
One of these photosensitive resins, APR (trade name, manufactured by Asahi Kasei) is the most representative product as a liquid photosensitive resin, and ALF, AWF, ASF (both are trade names) All manufactured by Asahi Kasei) are commercially available. As a plate making process using them, first, a photosensitive resin liquid is applied on a transparent carrier film with a uniform thickness, and after a base film is laminated thereon, another layer is previously formed on the laminated structure. By irradiating ultraviolet light through a transparent image carrier such as a negative film that selectively transmits ultraviolet light produced by the system, only the exposed photosensitive resin liquid is partially photocured to provide relief. By forming an image, then removing and recovering the uncured resin with a rubber blade, etc., and finally washing off the uncured resin remaining on the relief screen with a cleaning solution (developer), and then performing the necessary post-processing. A method of manufacturing a photosensitive resin relief printing plate supplied for printing is employed.

By the way, in the development process in which uncured resin is washed away, uncured resin is generally decomposed and removed with a developer having high chemical activity. When the resin is melted, the developing ability is reduced and the resin becomes unusable. Since this unusable developer cannot be discharged into sewage or the natural environment as it is, it must be entrusted to an industrial waste disposal contractor as cleaning waste. The amount is large and the disposal cost is high, which is an economic problem.
Further, currently, a post-exposure step is generally performed after the development step. This post-exposure step is a step for improving mechanical strength by curing unreacted materials inside and on the surface of the cured plate obtained by the development step, and further irradiating the printing plate with actinic rays. This is a process for reducing the surface tackiness of the cured plate. In this post-exposure step, in order to accelerate the polymerization reaction on the surface of the photosensitive resin layer, the photosensitive resin plate is immersed in a liquid to be shielded from oxygen in the air and irradiated with actinic rays in the liquid. However, performing the post-exposure step in a liquid means that the periphery of the plate making apparatus is contaminated and the workability is lowered, and there is a problem that the work environment is significantly lowered.

From the above situation, there is a strong demand for development of a method for reducing the disposal cost of used developer and a method for performing a post-exposure step in the air in order to improve the working environment.
On the other hand, for the development process, an aqueous developer in which high pressure is applied to the photosensitive layer of the object to be developed is described in Patent Document 1 (Kansai New Technology Research Institute “Pattern Forming Method and Photosensitive Resin Composition”). An example of a developing method sprayed from a spray nozzle is described. The developer used in this developing method is an aqueous developer and is substantially water. In the conventional development method, the chemical action by the surfactant contained in the developer is applied to decompose and remove the uncured resin. In the developing method in which the uncured resin is washed away using a developer containing no chemical component, a large physical energy is given to the relief surface by spraying the developer at a high pressure, and the uncured resin is scattered and removed.

Therefore, since it is not necessary to give the developer a chemical activity, water is sufficient as the developer. In this way, the cost of cleaning agents such as surfactants can be reduced, and the lifetime of the developer is not much dependent on the amount of uncured resin mixed in the developer, so compared with a developing method using a surfactant. As a result, the life of the developer is extended, thereby reducing the cost of disposal of the developer waste. However, this method can solve the problem of reducing the disposal cost of the developer, but there is a problem that a printing plate having a plate reproducibility with which a clear printing result can be obtained cannot be obtained. There is a problem in that a printing plate having plate reproducibility that can obtain a clear printing result cannot be obtained unless washing time is applied.
From the current situation as described above, developing a photosensitive resin relief plate that reduces the disposal cost of the used developer and produces a clear printing result in a developing time comparable to that of a conventional developing method using a surfactant. There is a strong demand for method development.

JP 2000-029227 A

  The present invention responds to this demand, and suppresses the generation amount of development waste liquid by circulating use of the developer with respect to the photosensitive resin relief plate after the exposure process, thereby reducing the waste liquid disposal cost and at the same time afterwards in the air. It is an object of the present invention to provide a plate making method that enables an exposure process.

As a result of intensive research in order to solve the above problems, the present inventor does not include a special cleaning liquid component in the developer, and uses an uncured resin by physical force using a high-temperature developer substantially composed of water. The knowledge that if removed from the printing plate and, if necessary, the developer contains a small amount of photosensitive hydrogen abstraction agent, a post-exposure in the air gives a photosensitive resin relief plate with no tackiness on the plate surface. As a result, the present invention has been completed.
That is, the present invention
(1) A method for developing a photosensitive resin relief plate comprising a step of spraying an aqueous developer at 40 ° C. or higher at a pressure of 1 MPa to 30 MPa to the photosensitive resin relief plate after exposure, wherein the aqueous developer is photosensitive. A method for developing a photosensitive resin relief printing plate, comprising a functional hydrogen abstracting agent, and the surfactant content in the aqueous developer is 0.5 wt% or less,
(2) The method for developing a photosensitive resin relief printing plate according to (1) above, wherein the aqueous developer is 55 to 65 ° C.,
It is.

  Since the method for developing a photosensitive resin printing plate according to the present invention performs high-pressure jet development utilizing physical action, printing plate development using an aqueous developer in which the photosensitive resin is insoluble is possible. Since it is easy to separate and remove the photosensitive resin from the used developer, it can be reused as a developer, reducing the amount of developer waste, which is advantageous for environmental conservation, and has a large waste disposal cost. Reductions can also be achieved.

The printing plate developing method of the present invention involves a rinsing step mainly using water and a post-exposure step by irradiation with actinic rays, if necessary, after jetting an aqueous developer on the printing plate under high pressure under specific conditions. It consists of a series of steps. First, the outline of the developing method and the developing apparatus according to the present invention will be described with reference to FIG.
FIG. 1 is a schematic view of an example of a developing device to which a developing method according to the present invention is applied. As shown in the figure, the developing apparatus according to the present invention includes a plate processing unit 200 for performing high-pressure spray development, and subsequent rinsing and post-exposure processing, and a solution tank unit 210 for storing and heating the developer. And a high-pressure jet pump 101 for increasing the pressure of the developer.

  First, the plate processing unit 200 is provided with a support 107 for fixing the photosensitive resin relief plate 108 to be developed with a clip or the like, and a high-pressure developer is sprayed toward the fixed photosensitive resin relief plate. A nozzle header 102 in which one or a plurality of spray nozzles 112 are arranged is installed in a direction perpendicular to the surface of the photosensitive resin relief plate. A high-pressure jet pump 101 is connected to the input side of the nozzle header 102 via a high-pressure dedicated hose 109 having excellent temperature resistance and pressure resistance. Further, the plate processing unit 200 is provided with a nozzle header 103 for injecting rinse water for washing away the developer remaining on the surface of the photosensitive resin relief plate after the high-pressure jet development processing. A tap water pipe 114 is connected to the input side of the nozzle header for rinsing water injection via a hose 111. Further, a gas blow nozzle 113 for blowing away the rinse water remaining on the surface of the photosensitive resin relief plate may be provided. Furthermore, for the purpose of removing stickiness on the surface of the photosensitive resin relief plate and improving the physical properties of the relief plate itself, a lamp in which one or more lamps that irradiate actinic rays in the air are arranged in parallel to the photosensitive resin relief plate surface A section 104 is provided.

The solution tank unit 210 is provided with a heater 106 that heats the developer to a predetermined temperature or keeps the developer at a predetermined temperature. Further, on the surface layer of the developer stored in the solution tank, a filter 105 such as an oil adsorption mat, a nonwoven fabric filter, a paper filter, etc. is installed as necessary to filter the liquid resin mixed in the developer. .
The high-pressure jet pump 101 constitutes a pressure source of this developing device. A solution tank 210 is connected to the input side of the high-pressure jet pump 101 via a hose 110. On the other hand, the output side of the high-pressure jet pump 101 is connected to a nozzle header 102 in which one or a plurality of nozzles 112 for spraying a high-pressure developer are arranged through a high-pressure dedicated hose 109.

  In the photosensitive resin relief printing apparatus having the above configuration, when the high-pressure jet pump 101 is driven, the developer heated to a predetermined temperature in the solution tank 210 is sucked into the high-pressure jet pump 101 and high pressure is applied. In this state, it is supplied to the nozzle header 102. The developer supplied to the nozzle header 102 is sprayed in a state of being atomized or equalized from the spray port of the spray nozzle 112. After the developer blown out from the spray nozzle 112 hits the photosensitive resin relief plate, the uncured resin is removed through the filter 105 and taken into the solution tank 210. Then, it is sucked into the high-pressure jet pump 101 through the hose 110 connected to the solution tank 210. Thereafter, after sufficient development, in order to wash away the developer remaining on the surface of the photosensitive resin relief printing plate, rinsing water sucked directly from tap water is sprayed from the nozzle header 103 for rinsing water injection. This rinse water is directly taken into the solution tank 210 as it is. After completion of the rinsing water treatment, if necessary, the gas is blown from the gas blow nozzle 113 onto the photosensitive resin relief plate to blow away the rinse water, and then the actinic ray lamp 104 is irradiated with actinic rays on the photosensitive resin relief plate. Perform exposure.

  As described above, the high-pressure spray developing method and apparatus according to the present invention using the developing method and apparatus for the photosensitive resin relief printing plate based on the configuration illustrated in FIG. Alternatively, it can be applied to a solid photosensitive resin printing plate. That is, exposure is performed on a printing plate structure obtained by laminating a cover film, a photosensitive resin, a base film, and a masking film in this order on a negative film on which a predetermined pattern is designed. After exposure, the cover film is peeled off, and if necessary, the uncured resin is recovered from the photosensitive resin letterpress main body to some extent with a rubber spatula or a gas knife, and then exposed to the plate processing section of the photosensitive resin letterpress developing device. After inserting and fixing the resin relief plate, the above-described high-pressure spray development can be performed.

Hereinafter, embodiments of the present invention will be described more specifically.
In the present invention, an aqueous developer is used. As used herein, the aqueous developer is sufficiently low in solubility or emulsifying action with respect to the uncured photosensitive resin to be removed, and the developer is easily regenerated by treating the development waste with a relatively simple method such as filtration. For example, depending on the type of the photosensitive resin of the printing plate to be developed, a developer whose main component is water having a surfactant content of 0.5 wt% or less is possible. Can be mentioned. This aqueous developer may contain other components other than water, for example, a small amount of a surfactant, alcohol, organic solvent, surface treating agent, etc. as long as they do not impair the effects of the present invention. .

  Conventionally, as an aqueous developer generally used as a developer for a liquid photosensitive resin, a solution containing 1 to 5% of an aqueous surfactant solution for developing by dissolving the resin by a chemical action is used. It is used. However, when this developing solution is used, the uncured resin removed in the developing step dissolves in the developing solution, making it difficult to remove only the resin component from the developing solution. Such a developer containing an uncured photosensitive resin not only lowers the resin solubility, but also adversely affects the tackiness removal of the printing plate surface in the post-exposure process described later. In contrast, the aqueous developer of the present invention is an aqueous developer containing almost no aqueous surfactant solution, and the hydrophobic resin component cannot be dissolved in the aqueous developer of the present invention. It is easy to remove only the uncured resin component from the used aqueous developer.

As described above, in the present invention, by using the aqueous developer, it becomes easy to separate the uncured resin and the developer contained in the aqueous developer after the development, and the circulating use of the developer, and thus the long life of the developer. Can be achieved. However, in the aqueous developer of the present invention, a photosensitive hydrogen abstracting agent for the post-exposure process described later, and other surfactants as needed, are added to such an extent that the life of the developer is not hindered. Various additives may be appropriately contained.
In addition, if the amount of the resin mixed in the aqueous developing solution in the developing step is not more than 4.0 parts by weight with respect to 100 parts by weight of the developing solution, a sufficient developing effect can be maintained.
In the present invention, the life of the developer can be further extended by installing filters at appropriate locations in the apparatus in order to separate and remove the resin component in the aqueous developer. For example, after spraying a developer onto a photosensitive resin printing plate, filters such as an oil adsorption mat, a nonwoven fabric filter, and a paper filter (FIG. 1) are formed on the surface layer of a solution tank (FIGS. 1 and 210) in which a used developer is stored. , 105). When the developer passes through these filters and returns to the solution tank, most of the uncured resin in the developer is filtered through the filter, and the aqueous developer can be recycled.

The aqueous developer of the present invention may contain a gas in order to improve the developing power when the developer is jetted. When the gas is mixed in the aqueous developer, the gas pressure is preferably 0.1 MPa or more. At a pressure lower than 0.1 MPa, no improvement in the development effect due to physical impact due to the mixing of gas is observed.
The aqueous developer of the present invention may contain an appropriate amount of a photosensitive hydrogen abstracting agent for the post-exposure step intended to remove the tackiness remaining on the plate surface after the development step. As the photosensitive hydrogen abstraction agent used in the present invention, for example, as in the photosensitive hydrogen abstraction agent described in JP-A-9-288356, a hydrogen atom of another compound is excited in the state excited by actinic ray irradiation. Organic carbonyl compounds that can be extracted are desirable. In this case, the hydrogen abstracting agent is another reaction caused by a photoexcited carbonyl group, in particular, a Norrish type 1 reaction, that is, a reaction in which a carbonyl compound undergoes its α-position cleavage under light irradiation, or 2 Compared to the self-cleavage reaction, in which the ketone with hydrogen that is extracted at the γ-position of the carbonyl group is cleaved into an olefin and a low-molecular-weight ketone compound under light irradiation, an organic compound that exhibits hydrogen abstraction reactivity that is comparable or higher Carbonyl compounds are suitable.

Representative organic carbonyl compounds that can be used as the photosensitive hydrogen abstraction agent of the present invention include, for example, benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4-chlorobenzophenone, 4-hydroxybenzophenone, 4-benzoyl. Substituted or unsubstituted benzophenones such as -4'-methyl-diphenyl sulfide, 3,3'-dimethyl-4-methoxybenzophenone, 4,4'-dichlorobenzophenone, 4-methylbenzophenone;
Acetophenone, 4′-methylacetophenone, 2 ′, 4′- or 3 ′, 5′-dimethylacetophenone, 4′-methoxyacetophenone, 2-chloro-2-phenylacetophenone, 3 ′, 4′-dichloroacetophenone, 4 ′ -Substituted or unsubstituted acetophenones such as hydroxyacetophenone;
Substituted or unsubstituted aromatic ketones such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoisobutyl ether;
Various types such as 1,4-benzoquinone, 2,6-dimethyl-1,4-benzoquinone, 2,6-dichloro-1,4-benzoquinone, anthraquinone, 2-chloroanthraquinone, 2-ethylanthraquinone, 1,4-naphthoquinone, etc. o, p-quinone compounds;
Various organic carbonyl compounds such as substituted or unsubstituted thioxanthones such as thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2-isopropylthioxanthone, and 2,4-dichlorothioxanthone can be used as the photosensitive hydrogen abstraction agent of the invention.

In the present invention, by jetting the aqueous developer containing the photosensitive hydrogen abstraction agent, the photosensitive hydrogen abstraction agent can be adhered and impregnated on the surface of the cured resin in the printing plate in the development step. By irradiating the printing plate with actinic rays in the air, a hydrogen abstraction reaction can be caused to sufficiently reduce the adhesiveness of the printing plate surface.
In order to sufficiently impregnate the printing plate with the photosensitive hydrogen abstraction agent in the development step, it is optimal that the photosensitive hydrogen abstraction agent is dissolved in the aqueous developer, but it is uniformly dispersed as a suspended state. Sufficient effect is exhibited. This uniformly dispersed state indicates a state where a required amount of the photosensitive hydrogen abstracting agent is dissolved and floated without being precipitated during development. In a state where the photosensitive hydrogen abstraction agent is not uniformly dispersed in the developer, for example, the photosensitive hydrogen abstraction that does not participate in the adhesion impregnation of the surface layer of the cured resin portion in the solution tank (FIGS. 1 and 210) of the developing device. In some cases, the adhesive precipitates and stays, so that a sufficient adhesive removal effect cannot be obtained after the post-exposure step. In addition, clogging with the photosensitive hydrogen abstraction agent crystallized at the spray nozzle (FIGS. 1 and 112) causes a drop in the spray pressure, which may cause a failure of the apparatus.

  Examples of the mixing method for uniformly dispersing the photosensitive hydrogen abstracting agent in the developer include the following methods. When the photosensitive hydrogen abstracting agent is dissolved or uniformly dispersed in the developer, the photosensitive hydrogen abstracting agent is directly added to the developer and mixed. Alternatively, a part of the developer may be separated and a mixture of a photosensitive hydrogen abstracting agent may be added to the developer. Many photosensitive hydrogen abstracting agents are solid at 10 to 20 ° C., and even if they are liquids, there are those that are not particularly dissolved or uniformly dispersed in an aqueous developer. In the present invention, when the developer is heated to 40 ° C. or higher, the photosensitive hydrogen abstracting agent seems to be uniformly dispersed even if it is directly added. However, depending on the type of the photosensitive hydrogen abstracting agent, the uniform dispersibility is poor. It is also possible to impart solubility or uniform dispersibility of the photosensitive hydrogen abstraction agent by adding a dispersion aid.

  The aqueous developer of the present invention is a printing plate after the exposure process at a high pressure of 1 MPa or more and 30 MPa or less in order to sufficiently exhibit the developing effect of the uncured resin due to physical impact when jetted onto the printing plate. It is preferable to inject. When the pressure is lower than 1 MPa, the development effect of removing the uncured resin by physical impact cannot be sufficiently exerted, and when the pressure is 30 MPa or more, the relief shape of the printing plate surface is damaged by the impact of the sprayed developer. Receive. In particular, an independent line having a line width of 500 μm or less and a highlight halftone dot having an area ratio of 5% or less may be chipped or peeled off from the printing plate, resulting in significant damage.

  The temperature of the aqueous developer used in the present invention needs to be 40 ° C. or higher. By setting the aqueous developer to 40 ° C. or higher, a printing plate having a plate quality equivalent to that of a conventional developing method using a surfactant can be prepared. The reason for this is that, for example, by contacting with a high temperature developer, the uncured resin that has not been cured in the exposure process is heated to reduce its viscosity, and the effect of removing the ineffective resin by physical impact in the development process is reduced. It is conceivable to improve dramatically. Also, in the post-exposure process using a photosensitive hydrogen abstraction agent, the solubility and uniform dispersibility of the photosensitive hydrogen abstraction agent in the developer are generally improved as the developer temperature is increased. Since the swelling of the surface increases and the amount of impregnation of the photosensitive hydrogen abstracting agent increases, the adhesive removal effect on the printing plate surface increases. In order to obtain a stable effect of removing the tackiness of the plate surface, the temperature of the developer is preferably maintained at 40 to 80 ° C, more preferably 55 to 65 ° C.

The development time in the present invention may be a time that can sufficiently wash away the uncured resin. For example, if the photosensitive resin plate has a thickness of 5 to 7 mm, the development time is 8 to 18 minutes. In the case where the aqueous developer contains a photosensitive hydrogen abstraction agent, the development time corresponds to the impregnation time of the photosensitive hydrogen abstraction agent in the resin cured portion. When trying to achieve the impregnation amount, other impregnation conditions such as developer temperature, content of photosensitive hydrogen abstraction agent in the developer, impact force of high-pressure spray developer applied to the surface layer of the cured resin part are adjusted. By doing so, the amount of impregnation of the photosensitive hydrogen abstracting agent can be controlled.

That is, the greater the impact force that the high-pressure spray developer gives to the surface of the cured resin portion, the greater the amount of the photosensitive hydrogen abstracting agent impregnated in the surface layer of the cured resin portion of the photosensitive hydrogen abstracting agent. Factors that increase the impact force that the high-pressure spray developer gives to the surface of the cured resin are (1) increase the water pressure, (2) increase the nozzle injection flow rate, and (3) the distance between the nozzle tip and the printing plate surface. It can be shortened.
Regarding the content of the photosensitive hydrogen abstraction agent in the developer, the type of the photosensitive resin composition, the type of the photosensitive hydrogen abstractor, the developer temperature, the development time, the developer water pressure, the nozzle injection flow rate, the nozzle and the printing plate The optimum content varies depending on the distance, the shape of the nozzle, etc., but in order to obtain a sufficient surface tack removal effect, the photosensitive hydrogen abstracting agent is 0.01 to 10 parts by weight with respect to 100 parts by weight of the developer. The amount is preferably 0.05 to 10 parts by weight. When the content is 0.01 parts by weight or less, the effect of removing the surface adhesiveness is not sufficient, and when the content exceeds 10 parts by weight, the increase in the effect of removing the surface adhesiveness is not observed.

Details of the developing device and the process of the present invention will be described below.
A typical developing device for carrying out the developing step discharges the developer at a pressure of 1 MPa to 30 MPa, and a nozzle header having one or more nozzles that inject the developer at a pressure of 1 MPa to 30 MPa. It consists of a pump that can In the development step, the direction of jetting or ejecting the developer is not particularly limited as long as the uncured resin can be removed, and may be slightly inclined with respect to the surface of the cured resin portion. On the other hand, the direction is substantially perpendicular (for example, about 0 to 15 ° with respect to the surface normal). The aqueous developer can be sprayed using a single nozzle or a plurality of nozzles (for example, a group of nozzles arranged in parallel), and the aqueous developer is sprayed or slitted while moving the nozzle. To do. In high-pressure spray development, the pressure may be constant, or development may be performed a plurality of times at different pressures. In the case of developing a plurality of times, for example, the type of the developer may be changed, such as a developer with a single water for the first time and an aqueous developer containing a photosensitive hydrogen abstractor for the second time. Good.
Note that the nozzle for jetting the developer at a high pressure may jet a gas mixed in the developer. As a nozzle for improving the collision force of the developing solution by mixing gas into the developing solution, that is, the developing force, for example, it is attached to the tip of the gun type discharge part of the multi-cleaning machine MUC1000 type (manufactured by Kajitani Industry Co., Ltd.) Nozzle etc. are mentioned.

  Further, as a developing solution heating apparatus, a heater for heating a developing solution is generally provided in a tank that stores the developing solution. In this case, since the heater with a large output can raise the temperature of the developer to the target temperature in a short time, the temperature of the developer may be lowered somewhat by spraying the developer during development. Even if it exists, this can be quickly returned to the target temperature, which is advantageous in controlling the temperature of the developer. The developer storage tank preferably has a capacity capable of storing at least 4 times the discharge flow rate per minute of the high-pressure pump used. For example, the storage amount of the developer tank is a discharge amount of 50 L per minute. If the pump having the above is used, the storage amount of the developer tank is preferably 200 L or more.

After completion of the above high-pressure spray development, in order to wash away the aqueous developer remaining on the surface of the photosensitive resin relief printing plate, water is sprayed on the printing plate surface to perform rinsing. The composition of the rinsing water is a single water, and the water pressure and jetting direction, time, temperature, and method of the rinsing water are not particularly limited as long as the developer remaining on the printing plate surface can be washed away. The rinse water is directly mixed in the developer, and thereafter used as a developer. In the developing step of the present invention, the developer is atomized by spraying the developer at a high temperature and a high pressure, whereby water in the developer composition is evaporated and the developer is reduced. Therefore, the amount of the developer can be kept constant by taking the rinse water into the developer. Unlike conventional highly active developers containing surfactants, even if rinsing water is mixed in the developer, the development effect is reduced due to a decrease in the proportion of the surfactant in the developer. There is no risk of expediting the replacement of waste liquid.

  After the rinsing process is completed, a water draining process using a gas blow nozzle is usually provided to remove the rinsing water remaining on the printing plate surface. The gas pressure and the jetting direction, time, temperature, and method of the gas blow are not particularly limited as long as the rinse water remaining on the printing plate surface can be blown off. If rinsing water remains on the surface of the printing plate, the portion of the photosensitive resin surface covered with the attached rinsing water in the post-exposure process to be performed later will inhibit oxygen more than the portion not covered with other rinsing water. Due to its good properties, the printing plate surface may become cloudy compared to the portion irradiated with actinic rays in air, or the surface tackiness may be different, and a uniform printing plate surface state may not be obtained.

After completion of the draining process, a post-exposure process is performed to improve the physical properties of the developed printing plate and remove the surface tackiness. In the post-exposure step, the printing plate is usually irradiated with ultraviolet rays having a wavelength of 200 to 400 nanometers in the air, such as a metal halide lamp, a low-pressure mercury lamp, a chemical lamp, or a germicidal lamp.
The appropriate exposure amount for obtaining a sufficient surface adhesive removal effect varies depending on the resin composition of the cured resin plate, the type of the photosensitive hydrogen abstraction agent, and the impregnation amount of the photosensitive hydrogen abstraction agent with respect to the resin composition, but at least 500 mJ / cm ^2. It is preferable to expose in the range of usually 1000 to 3000 mJ / cm ² . An exposure amount of 5000 mJ / cm ² or more is not preferable because fine cracks are generated on the plate surface.

The evaluation of the adhesiveness of the printing plate surface is, for example, in a state in which a polyethylene film is wound around the circumferential surface of a ring having a diameter of 50 mm made of an aluminum wire having a diameter of 13 mm and the aluminum plate is allowed to stand on the relief surface of the printing plate. Tack tester (Toyo Seiki Co., Ltd.) that puts a load of 500 g on the wheel and leaves it for 4 seconds, then pulls up the aluminum wheel at a speed of 30 mm per minute and reads the adhesive force when the aluminum wheel leaves the relief surface with a push bull gauge. Can be used. A smaller tack tester value (hereinafter referred to as tack value) can be said to be a printing plate having no surface tackiness. When the tack value exceeds about 50 g, foreign matter adheres to the surface of the printing plate and the printing plate is defective. When the tacking value exceeds 100 g, the plates are brought into close contact with each other when the printing plates are placed on top of each other. When the paper is paper, the phenomenon of paper smearing easily occurs due to adhesion between the printing surface and the paper. If the tack value is 30 g or less, it is considered that a problem due to adhesiveness cannot practically occur. In a liquid photosensitive resin printing plate that is considered to have particularly high adhesiveness among printing plates, the tack value generally exceeds 100 g when no treatment for removing surface adhesiveness is performed.
Next, it will be described in more detail that the aqueous developer of the present invention has a developing performance that is not inferior to or exceeds that of a conventional developer having high chemical activity by way of Examples and Comparative Examples. The technical scope and embodiments of the present invention are not limited to these examples.

Reference example (conventional development with chemical developer)
Photosensitive resin composition F-320 (manufactured by Asahi Kasei Co., Ltd., hereinafter referred to as liquid photosensitive resin A) ALF-II type plate making machine (manufactured by Asahi Kasei Co., Ltd.) was used to create a 7 mm plate that was completed up to the exposure step. . The exposure amount was set to appropriate exposure conditions that enable relief formation of a relief depth of 2 mm, a shelf layer of 5 mm, a back precipitation layer of 1 mm, and highlight formation of 45 LPI / 5%.
Surface treatment of 1.5% APR (registered trademark) washout agent capable of emulsifying liquid photosensitive resin A in 100 L of developer layer of ALF-400W type developing machine (drum rotating spray type, manufactured by Asahi Kasei Co., Ltd.) 0.5% of agent AX-10 (manufactured by Asahi Kasei Co., Ltd., photosensitive hydrogen abstraction agent) and 0.3% of antifoaming agent SH-4 (silicone blend, manufactured by Asahi Kasei Co., Ltd.) are dissolved in a developer. Was formulated.

Using a developing solution kept at 30 ° C. in advance, a 7 mm printing plate made of the liquid photosensitive resin A, which was completed up to the exposure step, was developed under conditions of a discharge water pressure of 0.2 MPa and a developing time of 10 minutes. Under this development condition, the development time per unit area is 1640 sec / m ² . Next, the developed plate is rinsed with tap water to such an extent that no bubbling due to the developer is observed, and then the UV-fluorescent lamp is 1000 mJ / cm ² and the germicidal lamp is 2000 mJ using an AL-200UP post-exposure machine (Asahi Kasei Co., Ltd.). In-air post-exposure was performed using an exposure dose of / cm ² . Thereafter, the plate was dried with an ALF-100P type dryer (Asahi Kasei Co., Ltd.) for about 30 minutes until water on the plate surface disappeared, and then left at room temperature for half a day to observe the printing plate.

  Although the printing part of the obtained liquid photosensitive resin A printing plate was evaluated by tactile sensation, it was confirmed that there was no stickiness although it had a slightly tight feeling. The appearance of the plate surface was cloudy and was not glossy. Moreover, the back deposit layer surface was in a slightly rough state visually. Moreover, the depth of the 500 μm line width white line was measured and was about 210 μm. The area ratio of 100 LPI / 90% halftone dot was also measured and found to be about 91%. Further, the line width of the printed portion of the 500 μm line width independent line was measured and found to be 524 μm (FIG. 2A). Next, the line width and depth of the 500 μm line width open line were measured, and the line width was 492 μm and the depth was 218 μm (FIG. 2B). The area ratio of 45 LPI / 5% halftone dot is 6.1% (FIG. 2C), and then the area ratio of 65 LPI / 30% halftone dot is 32.9% (FIG. 2D), which is more than the negative film design. Slightly larger value. Further, the formation state of a dot base portion of 45 LPI / 5% halftone dot was confirmed with a microscope, but a resin residue such as a slightly insufficient development was observed. FIG. 2 shows an enlarged view of the measurement part of the liquid photosensitive resin A printing plate by the above developing method.

Example 1 (High-temperature and high-pressure development with aqueous developer (1))
Photosensitive resin composition F-320 (manufactured by Asahi Kasei Co., Ltd., hereinafter referred to as liquid photosensitive resin A) ALF-II type plate making machine (manufactured by Asahi Kasei Co., Ltd.) was used to create a 7 mm plate that was completed up to the exposure step. . The exposure amount was set to appropriate exposure conditions that enable relief formation of a relief depth of 2 mm, a shelf layer of 5 mm, a back precipitation layer of 1 mm, and highlight formation of 45 LPI / 5%.
0.5% of surface treatment agent AX-10 (photosensitive hydrogen abstraction agent manufactured by Asahi Kasei Co., Ltd.) was dissolved in water to prepare a developer. The developer was put into a solution tank layer (capacity: 70 L) of an experimental machine for high-pressure spray development. Using a developing solution kept at 60 ° C. in advance, a plurality of 7 mm printing plates made of liquid photosensitive resin A, which has been completed up to the exposure process, in parallel with a plurality of high-pressure uniform fan nozzles VNP-1 / 8M-6549 (manufactured by Ikeuchi) Developed with the arranged nozzles under conditions of discharge water pressure 8.0 MPa, distance between nozzle and printing plate surface 100 mm, distance between each nozzle 100 mm, nozzle header moving speed 6.28 mm / sec, and nozzle header pass number of times. . Under these development conditions, the development time per unit area is 1590 sec / m ² . Next, the developed plate was rinsed with tap water to such an extent that no bubbling by the developer was observed, and the rinse water remaining on the surface of the rinsed plate was blown off with a gas gun. Thereafter, in-air post-exposure was performed with an AL-200UP type post-exposure machine (Asahi Kasei Co., Ltd.) using an ultraviolet fluorescent lamp at an exposure amount of 1000 mJ / cm ² and a germicidal lamp at an exposure amount of 2000 mJ / cm ² . Then, it was left at room temperature for about 30 minutes to see the printing plate.

The surface of the image (hereinafter, abbreviated as “printed portion”) used for printing of the obtained liquid photosensitive resin A printing plate was evaluated by touch, and it was confirmed that there was no tackiness. The appearance of the plate surface was transparent and seemed somewhat glossy. Further, the surface of the back deposited layer was visually very smooth.
Further, the line width of the printed part of the 500 μm line width independent line was 531 μm (FIG. 3A). Next, the line width and depth of the 500 μm line width open line were measured, and the line width was 478 μm and the depth was 270 μm (FIG. 3B). The area ratio of 45 LPI / 5% halftone dot is 5.1% (FIG. 3C), and then the area ratio of 65 LPI / 30% halftone dot is 33.7% (FIG. 3D), which is very faithful to the negative film design. It became the value. Further, the formation state of the dot base portion of 45 LPI / 5% halftone dot was confirmed with a microscope, but no particularly large damage or insufficient development was observed, and it was confirmed that the depth between dots was considerably deep. FIG. 3 shows an enlarged view of the measurement part of the liquid photosensitive resin A printing plate by the above developing method.

Example 2 (High-temperature and high-pressure development with a gas-containing aqueous developer)
A liquid photosensitive resin A was prepared under the same conditions as in Example 1.
Multi-washing with a nozzle of a gun type nozzle having a mechanism for mixing gas into high-pressure water from a 7 mm printing plate made of liquid photosensitive resin A that has been preliminarily exposed to an exposure process using water kept at 60 ° C. Machine MUC1000C type (manufactured by Kasuya Kogyo Co., Ltd.), discharge water pressure 10 MPa, discharge water amount 10 L / min, discharge gas pressure 0.3 MPa, discharge gas amount 1.6 m ³ / min, distance between nozzle and printing plate surface 150 mm, XY Development was performed under the conditions of an X-direction moving speed of 320 mm / sec at the table moving speed, a Y-direction moving pitch of 5 mm, and a nozzle header pass number of times. Under this development condition, the development time per unit area is 625 sec / m ² . Next, the developed plate was rinsed with tap water, and the rinse water remaining on the surface of the rinsed plate was blown off with a gas gun. Thereafter, in-air post-exposure was performed with an AL-200UP type post-exposure machine (Asahi Kasei Co., Ltd.) using an ultraviolet fluorescent lamp at an exposure amount of 1000 mJ / cm ² and a germicidal lamp at an exposure amount of 2000 mJ / cm ² . Then, it was left at room temperature for about 30 minutes to see the printing plate.
The appearance of the obtained liquid photosensitive resin A printing plate was evaluated, but no particularly large damage or uncured resin residue was found. The depth of the 500 μm line width white line was about 230 μm. The area ratio of 100 LPI / 90% halftone dot was about 90%. Further, the formation state of the dot root part of 45 LPI / 5% halftone dot was confirmed with a microscope, but no particularly large damage or insufficient development was observed.

Example 3 (High-temperature and high-pressure development with aqueous developer (2))
A liquid photosensitive resin A was prepared under the same conditions as in Example 1.
Water was used as a developer, and the developer was put into a solution tank layer (capacity: 70 L) of a high-pressure spray developing experimental machine. Using a developer kept at 40 ° C. in advance, a plurality of 7 mm printing plates made of liquid photosensitive resin A, which has been completed up to the exposure process, in parallel with a plurality of high-pressure uniform fan nozzles VNP-1 / 8M-6549 (manufactured by Ikeuchi) Developed with the arranged nozzles under conditions of discharge water pressure 8.0 MPa, distance between nozzle and printing plate surface 100 mm, distance between each nozzle 100 mm, nozzle header moving speed 6.28 mm / sec, and nozzle header pass number of times. . Under these development conditions, the development time per unit area is 1590 sec / m ² . Next, the developed plate was rinsed with tap water to such an extent that no bubbling due to the developer was observed. Thereafter, underwater post-exposure was performed with an AL-200UP type post-exposure machine (Asahi Kasei Co., Ltd.) using an ultraviolet fluorescent lamp at an exposure amount of 1000 mJ / cm ² and a germicidal lamp at an exposure amount of 2000 mJ / cm ² . Then, it was left at room temperature for about 30 minutes to see the printing plate.
The obtained liquid photosensitive resin A printing plate was confirmed, but the appearance of the plate surface was transparent and seemed somewhat glossy. Further, the line width of the print portion of the 500 μm line width independent line was 537 μm (FIG. 4A). Next, the line width and depth of a 500 μm line width white line were measured, and the line width was 478 μm and the depth was 240 μm (FIG. 4B). The area ratio of 45 LPI / 5% halftone dots was 7.4% (FIG. 4C), and then the area ratio of 65 LPI / 30% halftone dots was 37.0% (FIG. 4D). Further, the formation state of the dot base part of 45 LPI / 5% halftone dot was confirmed with a microscope, but no particularly large damage or insufficient development was observed. FIG. 4 shows an enlarged view of the measurement part of the liquid photosensitive resin A printing plate by the above developing method.

Example 4 (High-temperature and high-pressure development with aqueous developer (3))
A liquid photosensitive resin A was prepared under the same conditions as in Example 1.
Water was used as a developer, and the developer was put into a solution tank layer (capacity: 70 L) of a high-pressure spray developing experimental machine. In addition, using a developer kept at 60 ° C., a plurality of 7 mm prints made of the liquid photosensitive resin A, which has been completed up to the exposure process, are arranged in parallel with a high-pressure uniform fan nozzle VNP-1 / 8M-6549 (manufactured by Ikeuchi). Developed with the arranged nozzles under conditions of discharge water pressure 8.0 MPa, distance between nozzle and printing plate surface 100 mm, distance between each nozzle 100 mm, nozzle header moving speed 6.28 mm / sec, and nozzle header pass number of times. . Under these development conditions, the development time per unit area is 1590 sec / m ² . The developed plate was then rinsed with tap water to the extent that no bubbling due to the developer was observed. Thereafter, underwater post-exposure was performed with an AL-200UP type post-exposure machine (Asahi Kasei Co., Ltd.) using an ultraviolet fluorescent lamp at an exposure amount of 1000 mJ / cm ² and a germicidal lamp at an exposure amount of 2000 mJ / cm ² . Then, it was left at room temperature for about 30 minutes to see the printing plate.
The obtained liquid photosensitive resin A printing plate was confirmed, but the appearance of the plate surface was transparent and seemed somewhat glossy. The line width of the printed part of the 500 μm line width independent line was 535 μm. Next, the line width and depth of a 500 μm line width white line were measured, and the line width was 458 μm and the depth was 270 μm. The area ratio of 45 LPI / 5% halftone dots was 5.4%, and then the area ratio of 65 LPI / 30% halftone dots was 30.3%. Further, the formation state of the dot base part of 45 LPI / 5% halftone dot was confirmed with a microscope, but no particularly large damage or insufficient development was observed.

Comparative Example 1 (low temperature and high pressure development with aqueous developer)
A liquid photosensitive resin A was prepared under the same conditions as in Example 1.
Water was used as a developer, and the developer was put into a solution tank layer (capacity: 70 L) of a high-pressure spray developing experimental machine. Using a developing solution kept at 20 ° C. in advance, a plurality of 7 mm printing plates made of liquid photosensitive resin A, which has been completed up to the exposure process, in parallel with a plurality of high-pressure uniform fan-shaped nozzles VNP-1 / 8M-6549 (manufactured by Ikeuchi) Developed with the arranged nozzles under conditions of discharge water pressure 8.0 MPa, distance between nozzle and printing plate surface 100 mm, distance between each nozzle 100 mm, nozzle header moving speed 6.28 mm / sec, and nozzle header pass number of times. . Under these development conditions, the development time per unit area is 1590 sec / m ² . Next, the developed plate was rinsed with tap water to such an extent that no bubbling due to the developer was observed. Thereafter, underwater post-exposure was performed with an AL-200UP type post-exposure machine (Asahi Kasei Co., Ltd.) using an ultraviolet fluorescent lamp at an exposure amount of 1000 mJ / cm ² and a germicidal lamp at an exposure amount of 2000 mJ / cm ² . Then, it was left at room temperature for about 30 minutes to see the printing plate.

  The obtained liquid photosensitive resin A printing plate was confirmed, but the appearance of the plate surface was transparent, but it seemed that there was a considerable gloss due to a considerable amount of uncured resin residue. Further, the line width of the printed part of the 500 μm line width independent line was 527 μm (FIG. 5A). When the shoulder portion of the 500 μm line width independent line was confirmed with a microscope, there was considerable unevenness, and it seemed that the uncured resin still remained. Next, the line width and depth of the 500 μm line width white line were measured, and the line width was 449 μm and the depth was 170 μm (FIG. 5B). Similar to the 500 μm line width independent line, the 500 μm line width white line was confirmed with a microscope, and it seemed that a considerable amount of uncured resin remained inside the white line. Further, the area ratio of 45 LPI / 5% halftone dot was not measured because it was not sufficiently developed (FIG. 5C). Next, the area ratio of 65 LPI / 30% halftone dot could not be measured because it was not sufficiently developed as described above (FIG. 5D). The formation state of the dot base portion of 45 LPI / 5% halftone dot was confirmed with a microscope, but a considerable uncured resin residue was observed, and it was confirmed that the development was insufficient. FIG. 5 shows an enlarged view of the measurement part of the liquid photosensitive resin A printing plate by the above developing method.

  Since the method for developing a photosensitive resin printing plate according to the present invention performs high-pressure jet development utilizing physical action, printing plate development using an aqueous developer in which the photosensitive resin is insoluble is possible. Since it is easy to separate and remove the photosensitive resin from the used developer, it can be reused as a developer. This reduces the amount of waste developer, which is advantageous for environmental conservation and has a large waste disposal cost. Reductions can also be achieved.

1 is a diagram showing a schematic configuration of a developing device suitable for carrying out the present invention. 2A to 2D are enlarged photographs of a measurement part of a photosensitive resin printing plate obtained by a conventional chemical development method as a reference example. 3A to 3D are enlarged photographs of the measurement part of the photosensitive resin printing plate obtained in Example 1. FIG. 4A to 4D are enlarged photographs of the measurement part of the photosensitive resin printing plate obtained in Example 3. FIG. 5A to 5D are enlarged photographs of the measurement part of the photosensitive resin printing plate obtained in Comparative Example 1. FIG.

Claims (2)

  A photosensitive resin relief printing method comprising a step of spraying an aqueous developer at 40 ° C. or higher to a photosensitive resin relief after exposure at a pressure of 1 MPa to 30 MPa, wherein the aqueous developer is subjected to photosensitive hydrogen abstraction. A developing method for photosensitive resin relief printing, comprising an agent and having a surfactant content in the aqueous developer of 0.5 wt% or less.   The method for developing a photosensitive resin relief printing plate according to claim 1, wherein the aqueous developer is 55 to 65 ° C.

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