JP2001272789A - Photosensitive planographic printing plate and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an excellent photosensitive planographic printing plate 1) having a matte capable of attaining vacuum adhesion in a short time to such a degree that the printing plate can be satisfactorily adapted to a vacuum adhesion method, 2) having a matte with the necessary adhesive power, 3) not including a matte which causes trouble and 4) not including useless matte grains (grains out of the objective size), with respect to a photosensitive planographic printing plate having a matte on the plate surface by matting. SOLUTION: In the photosensitive planographic printing plate with a photosensitive layer having a matted surface on a base, the average diameter of the contact faces of the formed matte grains brought into contact with the plate surface is 4-50 μm, the average grain height is 2-20 μm and the dimensionless standard deviation of grain heights given by dividing the standard deviation of grain heights by the average grain height is <=0.7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION The present invention relates to a photosensitive lithographic printing plate, and more particularly to a photosensitive lithographic printing plate obtained by subjecting a surface of a photosensitive lithographic printing plate to mat processing by a spray method. About the edition.

The present invention relates to a method for producing a photosensitive lithographic printing plate, and more particularly to a method for producing a photosensitive lithographic printing plate having a step of matting the surface of the photosensitive lithographic printing plate by a spray method. About.

(Claims 36 to 38) The present invention relates to a method for producing a photosensitive lithographic printing plate. More particularly, the surface of the photosensitive lithographic printing plate is subjected to a matting process by a spray method and then subjected to a roller leveler to perform printing. The present invention relates to a method for producing a photosensitive lithographic printing plate by correcting the shape.

[0004]

2. Description of the Related Art Conventionally, in a plate-making process for producing a printing plate using a photosensitive printing plate, a vacuum printing frame is generally used to closely adhere a film original plate to the photosensitive printing plate. A method in which a film original plate and a photosensitive printing plate are overlapped and sandwiched between a glass plate and a rubber sheet of the baking frame and a vacuum is applied between the glass plate and the rubber sheet to make them adhere to each other (hereinafter, referred to as a vacuum adhesion method) is used. Have been.
A photosensitive printing plate having fine irregularities (hereinafter referred to as a mat) provided on the surface of a photosensitive layer in order to improve adhesion by a vacuum adhesion method is known.
No. 11102, a method of providing a coating layer composed of a fine pattern in which coated portions and non-coated portions are mixed on the surface of a photosensitive layer;
JP-A-5-12974 proposes a method of thermally fusing a solid powder, and JP-A-57-34558 proposes a method of providing a mat by spraying an aqueous solution in which a resin is dissolved or dispersed on the surface of a photosensitive layer.

According to this vacuum contact method, shortening the vacuum contact time is important in plate making operation, and the shape and amount of the mat are important factors.

Conventionally, in a plate-making process for producing a printing plate using a photosensitive printing plate, a vacuum contact method is generally used for contact printing of a film original on the photosensitive printing plate. . A photosensitive printing plate in which a mat is provided on the surface of a photosensitive layer in order to improve adhesion by a vacuum adhesion method is known.
No. 102, a method of providing a coating layer composed of a minute pattern in which coated portions and non-coated portions are mixed on the surface of a photosensitive layer;
No. 12974 discloses a method of heat-fusing a solid powder.
No. 34558 proposes a method of providing a mat by spraying an aqueous solution in which a resin is dissolved or dispersed on the surface of a photosensitive layer.

The above-mentioned Japanese Patent Application Laid-Open No. 57-34558 discloses a technique of forming a mat by spraying and drying an aqueous solution in which a resin is dissolved or dispersed on the surface of a photosensitive printing plate. Such aqueous solutions are advantageous in terms of safety during the production of the matting process by spraying. However, when a water-soluble resin is used as the material for forming the mat, the mat layer stains the film original plate at high humidity, and the mat layer has a weak adhesive strength with the photosensitive layer, and has no resistance to rubbing or pressure. In addition, there has been a problem that a part of the mat layer remains in the image area after development and the affinity for ink is hindered.

[0008] For the purpose of improving these, a copolymer containing acrylic acid, methacrylic acid, maleic acid or itaconic acid, part or all of which is an ammonium salt, as a substance forming a mat layer, and a monomer having a sulfonyl group Japanese Patent Application Laid-Open Nos. 57-58152 and 58-1 disclose a technique of forming a mat by spraying using a copolymer containing a simple substance.
No. 82636.

However, a photosensitive printing plate in which a mat is formed on the surface of a photosensitive layer using the above-mentioned water-soluble copolymer, can be removed from the mat when handled with bare hands at normal humidity. In other words, it is common practice to handle the printing plate with bare hands in the process of plate making, and take out the photosensitive printing plate from the box, place it on an exposure machine, or place it on the photosensitive printing plate before stacking the film master. There are many operations such as removing dust and dirt, and adjusting the position by stacking film masters, and these operations remove the mat. If the mat is removed, the time required for vacuum adhesion will increase, and if it is removed in the form of a spot, the size of the halftone dots will differ due to the difference in the adhesion between the film where the normal mat remains and the film. There was a problem that would occur.

[0010] Such a problem has been dealt with by providing a mat layer using a resin solution obtained by dissolving a resin in an organic solvent, in which case the formed mat may be exposed to humidity or bare hands. The problem that the mat could be removed by the above operation was improved. In addition, the number of combinations of the solvent type and the resin increases, and it is easy to obtain the desired adhesiveness and the strength of the completed mat.

(Claims 36 to 38) Conventionally, a roller leveler can be used as a means for correcting a shape defect of a metal plate such as a steel plate, a stainless steel plate, and an aluminum plate. The roller leveler transports a metal plate while being sandwiched from above and below by a plurality of small-diameter rolls, thereby causing the surface of the metal plate to undergo compositional deformation by repeated bending operations, thereby reducing the internal stress of the metal plate and flattening it.

On the other hand, a lithographic printing plate usually uses an aluminum plate as a support, and its surface is polished, roughened and modified mechanically, electrochemically and chemically. On the other hand, in these processes, stress is applied to the aluminum plate and "warpage" occurs, and after passing through multiple processes, it is bent by many transport support rolls, curling occurs,
Had been a problem. In order to correct these undesired deformations, it is common to correct the deformations with a roller leveler.

The process for producing a photosensitive lithographic printing plate can be broadly classified into surface treatment of a support, coating and drying of a photosensitive layer, mat processing (formation of a mat layer), overlapping of interleaving paper, and cutting. The matting process can be performed by dispersing solid particles as a matting agent in a photosensitive solution for forming a photosensitive layer and coating the photosensitive layer together with the photosensitive layer. Sometimes. For this reason, it is preferred that the mat layer be provided on the surface of the support in a mat processing step after forming the photosensitive layer. The correction of the support by the roller leveler is preferably performed at the end of the manufacturing process of the photosensitive lithographic printing plate in order to prevent undesired deformation during the processing step after the correction.

However, since the mat layer has a shape in which particulate resin adheres to the surface of the photosensitive layer, the mat layer is weak to stress and may fall off when correcting the printing plate shape by a roller leveler. In order to avoid this problem, if the roller leveler is placed before the mat processing after applying and drying the photosensitive layer, deformation may occur due to the bending of the printing plate by multiple rollers during transport after straightening Eventually, it is necessary to apply the roller leveler again, and in that order, the mat particles are crushed or dropped, or the printing plate is deformed or curled.

[0015]

(Claims 1 to 15) JP-A-58-137469 and JP-A-59-219751,
JP-A-2-122251 and JP-A-6-202339 describe a photosensitive printing plate in which the particle height and particle diameter are specified. It can be said that this is a more advanced technique in plate making work, but all particles are known in the art. It is very difficult and unnecessary to achieve the ranges described in the examples.

Specifically, if the mat particles are not in the desired shape, the vacuum contact time may be long or the adhesion to the photosensitive layer may be insufficient, or even if the particle diameter and particle height are within the target ranges, If the ratio of the two is poor, the adhesion to the photosensitive layer will be poor, and if the average value of the shape is large even in the target range, large particles that cause failure and the vacuum adhesion time will be shortened. The vacuum adhesion method using a mat is required to be improved, for example, small particles having no effect are mixed.

The present invention has been made in view of the above circumstances, and has as its object to provide a photosensitive lithographic printing plate which has been subjected to mat processing and has a mat on the plate surface. It has a mat that can be vacuum adhered in a short time, 2) it has a mat that has the required adhesive strength, and 3) it does not contain a mat that causes a failure, and 4) it does not contain waste mat particles (particles deviating from the target size). It is to provide an excellent photosensitive lithographic printing plate.

(Claims 16 to 28) By the way, when forming a mat by spraying, the following various problems have become apparent.

1) Unless the spray area of the spray liquid sprayed by the spray is set wider than the printing plate width, mat processing cannot be performed over the entire width of the printing plate.

2) At the edge of the printing plate, the particles are excessively adhered or the amount of adhered particles is insufficient depending on the conditions because of the air flow and electric singularity.

3) There is no optimal method for capturing and reusing overspray, and such a method is being studied. For example, Japanese Utility Model Application Laid-Open No. 59-39664 describes that overspray is captured by a falling liquid film. However, the amount of liquid used for the liquid film is large, and solid-liquid separation is difficult when the resin of the matting agent component is regenerated. Here, a group of mat particles that do not adhere to the photosensitive lithographic printing plate and scatter over a wider area than the plate width is referred to as overspray. 4) When the spray gun is fixed to the apparatus, the mat particles are exposed to the photosensitive lithographic printing plate in front of the spray gun. Spray is concentrated on the surface of the.

5) When the plate processing width to be subjected to mat processing is changed, the distance between the plate edge and the side wall of the spray chamber changes the flow of air at the edge, and the width distribution changes.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method of manufacturing a photosensitive lithographic printing plate in which a mat is formed on a printing plate by spraying to form a mat. Is performed uniformly in the width direction of the photosensitive lithographic printing plate to prevent contamination of the printing plate due to re-dispersion of mat particles adhering to the printing plate surface during spraying.

(Claims 29 to 35) When forming a mat by spraying, the following various problems have become apparent.

1) The temperature of the spray liquid sprayed by the spray,
The finish of the mat changes over time due to fluctuations in the liquid physical properties and the temperature and humidity in the spray booth related to drying during the scattering of the sprayed droplets.

2) When an organic solvent is used as the spray liquid, the finish of the mat changes over time if the vapor pressure of the organic solvent in the spray booth fluctuates.

3) Particles having different particle sizes are mixed in the particles of the spray liquid sprayed by the spray, which adversely affects the finish of the printing plate.

4) Adhesion of droplets in the spray booth not only causes loss but also causes contamination of the printing plate due to re-scattering.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method of manufacturing a photosensitive lithographic printing plate in which a mat is formed on a printing plate by spraying to form a mat. The purpose of the present invention is to provide a high quality matting process by removing unnecessary particles at the time of spray spraying, to further reduce the loss of the spray liquid, and to prevent contamination of the photosensitive lithographic printing plate due to re-scattering.

(Claims 36 to 38) The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a system for correcting the shape of a printing plate by applying a roller leveler after a mat processing step to surely correct the shape of the printing plate. To provide a manufacturing method in which the mat particles formed in the mat processing step are not crushed or dropped.

[0031]

The above object of the present invention is attained by the following constitutions.

(Claims 1 to 15) In a photosensitive lithographic printing plate having a photosensitive layer on a support, and the surface of the photosensitive layer is matted, the average contact surface of the formed matting particles with the plate surface has a diameter of 4 to 50 μm.
m, the average particle height is 2 to 20 μm, and the dimensionless standard deviation of the particle height obtained by dividing the standard deviation of the particle height by the average particle height is 0.7 or less. .

2. In a photosensitive lithographic printing plate having a photosensitive layer on a support and the surface of the photosensitive layer being mat-processed, the average particle diameter of the formed matting particles in contact with the plate surface is 4 to 50 μm. The height is 2 to 20 μm, and (average particle height) / (average diameter of the contact surface with the plate surface) is 0.
A photosensitive lithographic printing plate, wherein the ratio is 2 to 0.7.

3. In a photosensitive lithographic printing plate having a photosensitive layer on a support and the surface of the photosensitive layer being mat-processed, the average particle diameter of the formed matting particles in contact with the plate surface is 4 to 50 μm. A photosensitive lithographic printing plate characterized in that the number of particles having a height of 2 to 20 μm and the diameter of a contact surface with the plate surface being 100 μm or more is 1% or less of the total number of particles.

4. In a photosensitive lithographic printing plate having a photosensitive layer on a support, and the surface of the photosensitive layer is matted, the formed matte particles have an average contact surface with the plate surface having a diameter of 4 to 50 μm, A photosensitive lithographic printing plate having a height of 2 to 20 [mu] m and the matting particles satisfy the following formula:

(Average particle height (μm)) ^5/2 × (Amount of particles attached (g / m ² )) ^1/5 > 10 That is, the inventions according to the first to fifteenth aspects of the present invention adopt plate making by a vacuum adhesion method. When forming the mat necessary for the formation of the mat on the surface of the photosensitive lithographic printing plate, the processed mat particles have a certain distribution in size. It was made based on the knowledge that an effective evaluation can be made only when the evaluation is made.
In addition, it is not preferable to independently evaluate the particle diameter and the particle height because flat particles and particles having a small particle diameter are mixed with the particle height. It is important to make a comprehensive judgment including the amount of

(Claims 16 to 28) 5. In a method for producing a photosensitive lithographic printing plate in which a matte process is performed by a spray method on a surface of a photosensitive lithographic printing plate having a photosensitive layer on a support, a spraying range of a spray used is wider than a plate width of the photosensitive lithographic printing plate. The set and trapped particles sprayed off the plate surface are captured by catching plates provided outside both sides in the conveying direction of the photosensitive lithographic printing plate, and the catching plate is moved in the traveling direction of the photosensitive lithographic printing plate. A method for producing a photosensitive lithographic printing plate, comprising:

6. In a method for producing a photosensitive lithographic printing plate in which a matte process is performed by a spray method on a surface of a photosensitive lithographic printing plate having a photosensitive layer on a support, a spraying range of a spray used is wider than a plate width of the photosensitive lithographic printing plate. The particles set and sprayed off the plate surface are captured by a suction plate having suction ports provided outside both sides in the conveying direction of the photosensitive lithographic printing plate, and the suction plate and the photosensitive lithographic printing plate are captured. Wherein the distance in the vertical direction of the plate surface is 30 mm or less.

7. In a method for producing a photosensitive lithographic printing plate, in which a surface of a photosensitive lithographic printing plate having a photosensitive layer on a support is subjected to a matting process by a spray method, a side wall of a spray chamber is adjusted to a width of the photosensitive lithographic printing plate to be processed. A method for producing a photosensitive lithographic printing plate, characterized by changing the position of the lithographic printing plate.

(Claims 29 to 35) In the method for producing a photosensitive lithographic printing plate, in which a surface of a photosensitive lithographic printing plate having a photosensitive layer on a support is matted by a spray method, a temperature of a spray liquid from a spray booth to be used is in a range of 20 to 27 ° C. With a median within
Temperature fluctuation during spraying is within the median ± 2 ° C and viscosity is 5
Has a median value in the range of ~ 200 mPa · s, the viscosity fluctuation during spraying is within the median value ± 2 mPa · s, and the surface tension has a median value in the range of 0.02 to 0.08 N / m. And
The tension fluctuation during spraying is within the median ± 0.001 N / m, and the temperature set value of the spray liquid in the spray booth is 20
It has a median value within the range of ~ 27 ° C, and the temperature fluctuation is ±
A method for producing a photosensitive lithographic printing plate, wherein the temperature is within 2 ° C., the humidity set value has a median within a range of 30 to 50%, and the humidity fluctuation is within the median ± 3%.

9. In a method for producing a photosensitive lithographic printing plate in which a matte process is performed by a spray method on a surface of a photosensitive lithographic printing plate having a photosensitive layer on a support, a spray liquid in a spray booth used has at least an organic solvent and a resin. And the vapor pressure of the organic solvent is の of the lower explosive limit.
Or less, and the vapor pressure has a median value in the range of 0.01 to 1% of the saturated vapor pressure of the organic solvent, and the fluctuation of the saturated vapor pressure during spraying is within ± 0.005% of the median value. A method for producing a photosensitive lithographic printing plate.

10. In a method for producing a photosensitive lithographic printing plate, in which a surface of a photosensitive lithographic printing plate having a photosensitive layer on a support is subjected to a matting process by a spray method, a spray liquid is provided between a spray atomizer used and the printing plate. A method for producing a photosensitive lithographic printing plate, comprising a means for capturing or repelling a portion.

(Claims 36 to 38) After performing a matting process by a spray method on the surface of a photosensitive lithographic printing plate having a photosensitive layer on a support, a photosensitive lithographic printing plate is subjected to a roller leveler for correcting the printing plate shape using a plurality of rollers. in the manufacturing method, a manufacturing method of the photosensitive lithographic printing plate, wherein the tension of the photosensitive lithographic printing plate at the time of the roller leveler passage is 0.2~0.7kg / m ^2.

12. After performing a matting process by a spray method on the surface of a photosensitive lithographic printing plate having a photosensitive layer on a support, a photosensitive lithographic printing plate is subjected to a roller leveler for correcting the printing plate shape using a plurality of rollers. A method for producing a photosensitive lithographic printing plate, characterized in that a surface of a roller which is in direct contact with the photosensitive lithographic printing plate is coated with a material having a hardness lower than a hardness of a material forming a mat layer.

13. After performing a matting process by a spray method on the surface of a photosensitive lithographic printing plate having a photosensitive layer on a support, a photosensitive lithographic printing plate is subjected to a roller leveler for correcting the printing plate shape using a plurality of rollers. A method for producing a photosensitive lithographic printing plate, comprising: interposing a slip sheet between a surface provided with a photosensitive layer and the roller to correct the shape of the printing plate.

The invention according to claims 36 to 38 of the present invention is a method in which a method for producing a photosensitive lithographic printing plate is selected in the order of a mat processing step and a step of performing a roller leveler to correct the shape of the printing plate. The present invention has been found to achieve the object by adopting three different means for the purpose of preventing obstacles such as crushing or falling off of mat particles while reliably correcting the metal plate. It has been reached. That is, 1) the photosensitive lithographic printing plate is set to a specific tension when passing through the roller leveler. 2) A mat layer is formed on the surface of a roller (also referred to as a work roller) that directly contacts the photosensitive lithographic printing plate constituting the roller leveler. 3) coating with a material having a hardness lower than the hardness of the material to be formed; 3) before applying the roller leveler, by providing a process of stacking a slip sheet between the surface on which the photosensitive layer is provided and the roller. It has been made based on the finding that the above-mentioned problem is solved.

Hereinafter, the present invention will be described in detail. (Claims 1 to 15) In the photosensitive lithographic printing plate according to claim 1 of the present invention, the average particle diameter of the contact surface of the mat particles formed on the plate surface with the plate surface is 4 to 50 μm, and the average particle height is And the dimensionless standard deviation of the particle height obtained by dividing the standard deviation of the particle height by the average particle height is 0.2 to 20 μm.
7 or less.

In order to shorten the vacuum adhesion time, it is necessary to improve the height, diameter and number of particles of the mat.

Regarding the particle diameter of the mat, the diameter of the contact surface with the average plate surface of the photosensitive lithographic printing plate may be 4 to 50 μm, preferably 10 to 20 μm. When the diameter of the contact surface with the average plate surface of the plate is less than 4 μm,
The vacuum contact time tends to be long, and if the height of the mat is increased in order to shorten the vacuum contact time, the adhesion to the photosensitive layer becomes poor. Also, if the number of particles is increased to shorten the vacuum contact time, the area covering the photosensitive layer becomes large, so that the photosensitive layer cannot be effectively exposed at the time of exposure, leaving a problem in the non-image area. Therefore, the particle size of the mat is 4μ.
When the particle diameter is less than m, that is, when the particle diameter is extremely small, it is difficult to obtain a stable particle diameter, and the number of particles effective for obtaining a vacuum adhesion time decreases. On the other hand, if it exceeds 50 μm, the area covering the photosensitive layer becomes large, so that the photosensitive layer cannot be effectively exposed at the time of exposure, and there is a problem that a residue is left in a non-image area. In addition, when a solvent that dissolves the photosensitive layer is used, the performance of the photosensitive layer is changed, so that a drop or a residue may occur. In addition, the size of the mat becomes the same order as the dot size, and the exposure state may change between a portion having a mat and a portion not having the mat, and even if the particle size of the mat exceeds 50 μm, that is, even if the particle size is too large, vacuum adhesion is required. Not preferred.

Regarding the particle height of the mat, the average particle height may be 2 to 20 μm, preferably 2 to 10 μm.
m. When the average particle height is less than 2 μm, the vacuum contact time tends to be long, and when the particle size of the mat is increased to shorten the vacuum contact time, the area covering the photosensitive layer increases, and the photosensitive layer is effectively used during exposure. There is a problem that the non-image area cannot be exposed and the non-image area remains. In addition, when a solvent that dissolves the photosensitive layer is used, the performance of the photosensitive layer is changed, resulting in a drop and a residue.

If the number of particles is increased in order to shorten the vacuum contact time, the area covering the photosensitive layer becomes large, so that the photosensitive layer cannot be effectively exposed at the time of exposure, and there is a problem that a residue is left in a non-image area. Therefore, the average particle height of the mat is 2
If it is less than μm, that is, if it is too low, it becomes difficult to adjust the particle height to a stable value, and the number of particles effective for obtaining a vacuum adhesion time decreases. On the other hand, when it is higher than 20 μm, the mat tends to be easily caught and easily removed. In addition, it becomes weak against the pressing pressure, and can be obtained by one exposure, so that a plurality of exposures cannot be performed.

Thus, there is a problem that the distance between the film and the photosensitive layer is different between the portion having the mat and the portion having no mat, and the size of the halftone dot is different.

The dimensionless standard deviation of the particle height obtained by dividing the standard deviation of the particle height by the average particle height, that is, the standard deviation of the particle height / the average particle height may be 0.7 or less, and is preferable. Is 0.5 or less. When the dimensionless standard deviation of the particle height exceeds 0.7, the number of particles effective for obtaining the vacuum adhesion time is reduced, or flat large particles that are slow to dry are mixed and become the same size as the halftone dot size, There is a problem that the exposure state changes between a portion having a mat and a portion not having the mat, and small particles that erect quickly and are mixed into the mat, resulting in poor adhesion to the photosensitive layer.

The photosensitive lithographic printing plate according to claim 3 of the present invention requires that (average particle height) / (average diameter of the contact surface with the plate surface) be 0.2 to 0.7, Preferably it is 0.3-0.6. If it is less than 0.2, if the particle size is increased to shorten the vacuum adhesion time, the area covering the photosensitive layer becomes large, and the photosensitive layer cannot be effectively exposed at the time of exposure, and the non-image portion remains, When a solvent that dissolves the layer is used, the performance of the photosensitive layer will be changed, resulting in dropout and residue.If the number of particles is increased to shorten the vacuum adhesion time, the area covered by the photosensitive layer will increase and the photosensitive layer will be effective during exposure. There is a problem that the non-image area cannot be exposed and the non-image area remains. On the other hand, when it exceeds 0.7, there is a problem that it is easy to be caught and easily taken out during handling, or is weak against a pressing pressure, so that it can be taken out by one exposure and cannot be exposed a plurality of times.

The photosensitive lithographic printing plate according to claim 6 of the present invention is characterized in that the number of particles at which the diameter of the contact surface with the plate surface is 100 μm or more is 1% or less of the total number of particles. When particles having a diameter of the contact surface of 100 μm or more are present, vacuum adhesion can be performed in a short time enough to be sufficiently applicable to the vacuum adhesion method.

The photosensitive lithographic printing plate according to claim 8 of the present invention is characterized in that the matting particles satisfy the following expression. That is, (average particle height (μm)) ^5/2 × (particle attached amount (g /
m ² )) ^1/5 > 10. In this regard, the matting particles need only be above 10, and the vacuum adhesion time is short, which is preferable. It is also preferably above 20.

In the photosensitive lithographic printing plate of the present invention, the number of matting particles present on the plate surface is preferably from 10 to 1000 / mm ² , more preferably from 100 / mm ^2.
７００700 / mm ² .

In the present invention, the amount of the matte particles present on the plate surface is preferably from 0.005 to 0.5 g / m ² , more preferably from 0.05 to 0.4 g / m ^2.
/ M ² .

In the present invention, the area occupied by the mat particles present on the plate surface is preferably from 0.3 to 50%, more preferably from 10 to 45%.

The number of mat particles existing on the plate surface is 1
Less than 0 / mm ² , or 0.005 g /
When it is less than m ² or less than 0.3% of the area occupied by the mat particles, the vacuum adhesion time tends to be long.

On the other hand, when the number of particles is more than 1000 particles / mm ² , the amount of particles attached is more than 0.5 g / m ² , or the area occupied by the mat particles is more than 50%, the area covering the photosensitive layer is large. In other words, the photosensitive layer cannot be effectively exposed at the time of exposure, and the non-image portion tends to remain.

Next, a description will be given of the apparatus conditions when matting a photosensitive planographic printing plate. Although there is no particular limitation for performing the mat processing, it is optimal to employ an electrostatic spray method. The electrostatic spray method uses an electrostatic spray gun, for example, an electrostatic spray gun as shown in FIG. The electrostatic spray gun 1 is provided with a bell 2 at a discharge port for discharging a mat droplet. The rotation of the bell controls the amount of the spray particles 3, the discharge speed, and the like. Generally, when the peripheral speed of the bell is increased, the diameter of the spray droplet becomes smaller, and when the spray distance (the distance between the bell and the plate surface to be sprayed) becomes longer, the diameter of the formed mat particle becomes smaller and the height becomes higher. When the voltage applied to the bell is increased in order to impart electric charge to the liquid droplets and improve the directivity to the plate surface, the efficiency expressed by the adhesion amount with respect to the spray amount is improved.

In order to form the mat desired in the present invention on the plate surface, the peripheral speed of the outer periphery of the bell should be 10 to 120 m / sec.
Spray distance 200-800mm, applied voltage -10-
Preferably, it is 100 kV.

If the peripheral speed of the outer periphery of the bell is lower than 10 m / sec, the particle diameter formed on the printing plate becomes too large, the area covering the photosensitive layer becomes large, and the photosensitive layer cannot be effectively exposed at the time of exposure. There is a problem that the image portion remains. In addition, when a solvent that dissolves the photosensitive layer is used, the performance of the photosensitive layer is changed, so that a drop or a residue may occur. In addition, the uniformity of the particle diameter is deteriorated, and the number of particles effective for obtaining the vacuum contact time is reduced. On the other hand, if the peripheral speed of the outer periphery of the bell is higher than 120 m / sec, the particle diameter formed on the plate surface becomes too small, and the vacuum adhesion time tends to be long. If the size is increased, the adhesion to the photosensitive layer becomes poor. Also, if the number of particles is increased to shorten the vacuum contact time, the area covering the photosensitive layer becomes large, so that the photosensitive layer cannot be effectively exposed at the time of exposure, and there is a problem that a non-image portion remains.

If the spraying distance is shorter than 200 mm, the solvent evaporation time from the scattered droplets is insufficient, and the particles formed on the plate surface are (average particle height) / (average diameter of the contact surface with the plate surface). Is less than 0.2 which is too flat. Conversely, if the spraying distance exceeds 800 mm, the solvent evaporation time from the droplets being scattered is too long, and the particles formed on the plate surface are (average particle height) / (average diameter of the contact surface with the plate surface).
Is 0.8 or more in a shape that is easy to peel off.

When the applied voltage is smaller than -10 kV,
Not only does the number of particles reaching the plate surface decrease and the efficiency deteriorates, but the particles come into contact with each other during scattering and become larger than intended. Conversely, when the applied voltage is higher than -100 kV, not only the power efficiency is degraded due to excessive power consumption, but also the danger of discharging comes out.

When matting is performed with an electrostatic spray gun, the electrostatic spray gun is swung in a direction perpendicular to the plate conveying direction in order to apply uniform matting in the width direction of the photosensitive lithographic printing plate. The spray gun is tilted as shown in FIG. FIG. 2 is a schematic view of a step of applying a matting process to the photosensitive lithographic printing plate 4 as an object to be sprayed by an electrostatic spray gun as viewed from above. At this time, the angle between the vertical direction of the printing plate and the spraying direction is preferably 10 ° or less. If it is larger than 10 °, the change in the distance from the spray gun in the width direction of the printing plate becomes too large, so that (average particle height) / (average diameter of the contact surface with the printing plate) differs in the width direction of the printing plate. The vacuum contact time differs in the width direction of the plate surface. The angle between the vertical direction of the plate surface and the spraying direction is preferably not more than 10 ° not only in the width direction but also in the plate conveying direction. If the angle is larger than 10 °, mats having different (average particle height) / (average diameter of the contact surface with the plate) are mixed on the same plate due to variation in spray distance, and mats having substantially different particle diameters and heights are present. Is formed.

(Claims 16 to 28) In the method for producing a photosensitive lithographic printing plate according to the present invention, when the surface of the photosensitive lithographic printing plate is subjected to a matting process by a spray method, the range of the spray used is a photosensitive lithographic printing plate. Particles which are set wider than the plate width of the printing plate and which are sprayed off the plate surface are captured by capture plates provided outside both sides in the transport direction of the photosensitive lithographic printing plate, and the capture plate is provided with the photosensitive plate. The lithographic printing plate is moved in the traveling direction.

The airflow at the edge of the plate is disturbed by the entrained air accompanying the transport of the photosensitive lithographic printing plate, whereby the spray airflow is disturbed and the amount of mat particles attached at the edge fluctuates, resulting in excessive or undersized. However, it was difficult to perform a uniform mat processing. By moving the catching plate that catches the sprayed particles off the plate surface in the direction of travel of the printing plate,
Disturbance of the airflow at the edge of the printing plate is eliminated, and the mat processing becomes a uniform process.

In particular, it is preferable that the moving speed of the catching plate is the same as the transport speed of the printing plate, and the turbulence of the air flow at the edge of the printing plate can be minimized by making it the same speed. .

In the present invention, it is preferable that the catching plate used is in the form of a belt, and in particular, a winding type belt or an endless belt is optimal. The material is preferably a Teflon sheet or a pressure-sensitive adhesive sheet. The Teflon sheet is advantageous in that it is easy to clean, and the pressure-sensitive adhesive sheet is advantageous in that the adhered particles are unlikely to be scattered again. Can be performed sufficiently.

In the present invention, the spray liquid sprayed from the spray used is a liquid formed by dissolving or dispersing the spray liquid particle components in an organic solvent, or both, and is captured by the capture plate. It is preferable that the spray liquid particle component is dissolved and removed with an organic solvent used as a solvent of the spray liquid, and then used again as a spray liquid. That is, the organic solvent used as the solvent of the spray liquid is preferable as the washing liquid of the matte particle component of the spray liquid captured by the capture plate in terms of reuse.

In the present invention, it is preferable that the organic solvent for dissolving the matte particle component of the spray liquid captured by the capturing plate has a boiling point of 80 ° C. or lower and has a fast drying property. If the concentration of the solvent after washing the trapped mat particle component is lower than that of the spray liquid, concentration is required for reuse, and therefore, it is preferable to use a solvent having a low boiling point as much as possible. The use of a low-boiling solvent speeds up drying of the solution and promotes reuse as a solute. Specifically, those having a boiling point of 80 ° C. or less are preferable, and the effects thereof include good drying properties and good work efficiency.

In the present invention, the catching plate is on the back side of the photosensitive lithographic printing plate, the distance between the catching plate and the photosensitive lithographic printing plate in the vertical direction of the plate surface is 5 to 50 mm, and Are preferably provided so as to overlap in the width direction of the photosensitive lithographic printing plate. In order to eliminate the turbulence of the airflow at the edge of the printing plate due to the entrained air by moving the capturing plate, the distance in the vertical direction of the printing plate needs to be 50 mm or less,
5m to prevent contact between capture plate and photosensitive lithographic printing plate
m or more is required. Further, if there is no overlap in the width direction between the capturing plate and the photosensitive lithographic printing plate, the disturbance of the flow at the end cannot be canceled by the movement of the capturing plate.

Another aspect of the present invention is a method of performing a matting process by a spray method, wherein a spraying range of a spray to be used is set to be wider than a plate width of a photosensitive lithographic printing plate, and the spraying is performed outside a plate surface. The captured particles are captured by a suction plate having suction ports provided outside both sides in the transport direction of the photosensitive lithographic printing plate, and the distance between the suction plate and the photosensitive lithographic printing plate in the vertical direction of the plate surface is 30 mm. It is characterized by the following.

In the present invention, it is preferable that the method for performing the matting process by the spray method is the electrostatic spray method, and that the capturing plate or the suction plate having the suction port has the same potential as the photosensitive lithographic printing plate. When using an electrostatic spray gun, by setting the same potential as the photosensitive lithographic printing plate, the method of attaching particles between the capture plate or suction plate and the photosensitive lithographic printing plate is the same, and the edge of the printing plate is unique. A uniform matting process can be performed in the width direction without using dots.

In the present invention, whether the spray gun swings in the width direction of the photosensitive lithographic printing plate, or changes the angle of the photosensitive lithographic printing plate from the plate surface vertical direction to the width direction,
Alternatively, it is preferable to make the spraying range wider than the plate width of the photosensitive lithographic printing plate by performing both. In this case, it is preferable that the speed of the swinging of the spray gun and / or the angle change of the spray gun is equal to or higher than the transport speed of the photosensitive lithographic printing plate. It prevents unevenness in the mat processing along with the axis trace drawn on the plate surface). In this case, a plurality of spray guns may be used, or one or a plurality of spray guns may be oscillated. When a plurality of spray guns are oscillated, it is preferable to work on the printing plate without gaps in conjunction therewith.

Another aspect of the present invention is a method of performing mat processing by a spray method, wherein the position of the side wall of the spray chamber is changed according to the plate width of the photosensitive lithographic printing plate to be processed. This is preferable because the flow of the air stream at the end is stable and the particle distribution in the width direction is constant.

That is, when the plate width of the photosensitive lithographic printing plate is wide, the position of the side wall of the spray chamber is widened, and when the plate width is small, the position of the side wall of the spray chamber is narrowed. At this time, the distance from the edge of the photosensitive lithographic printing plate to the side wall is not constant,
It is preferable to confirm in advance the appropriate point where the flow of the air current is stable.

(Claims 29 to 35) A method for producing a photosensitive lithographic printing plate according to the present invention is a method for producing a photosensitive lithographic printing plate which performs matting by a spray method, wherein a spray liquid from a spray booth to be used is used. Has a median value in the range of 20 to 27 ° C., the temperature fluctuation during spraying is within the median ± 2 ° C., and the viscosity has a median value in the range of 5 to 200 mPa · s. The median viscosity variation was within ± 2 mPa · s, the surface tension had a median value in the range of 0.02 to 0.08 N / m, and the
01 N / m or less, and the temperature set value of the spray liquid in the spray booth has a median value in the range of 20 to 27 ° C.,
Temperature fluctuation is within ± 2 ° C of the median, and humidity setting is 30
The median value is within the range of ~ 50%, and the humidity fluctuation is ±
It is characterized by being within 3%.

In the present invention, it is necessary that the temperature of the liquid sprayed from the spray booth has a median value in the range of 20 to 27 ° C., and that the temperature fluctuation during spraying be within the median value ± 2 ° C. The reason for this is that it is preferable to manage at a temperature close to room temperature in terms of energy efficiency. In particular, the viscosity of the spray liquid in the spray booth is easily affected by temperature changes, and it is good to set the liquid physical properties as close as possible to room temperature so that the liquid properties do not change over time due to temperature changes. This is preferable for forming a natural mat. As a means for achieving this, there is a method in which a thermal insulation jacket is provided in a spray liquid tank, a pipe, or the like, and the temperature is kept constant.

The viscosity of the spray liquid from the spray booth is 5 to
It has a median value within the range of 200 mPa · s, and it is necessary that the viscosity fluctuation during spraying is within the median value ± 2 mPa · s. If the particle size is too low, particles of the required size cannot be obtained, while if it is too high, the particles become too large,
This is due to uneven mat particle size. If it fluctuates from the above settings, the size and spread of the particles will change,
A photosensitive lithographic printing plate having a mat of constant quality cannot be obtained.

It is necessary to carry out viscosity measurement and fine adjustment at the time of preparing the spray liquid for each lot. That is, the spray liquid is usually obtained by dissolving the resin in a solvent, but the viscosity may differ from lot to lot due to a weighing error of the material or the like. Therefore, it is preferable that the viscosity be measured for each lot and finely adjusted. The viscosity is measured with a B-type viscometer.

The surface tension of the sprayed liquid from the spray booth has a median value in the range of 0.02 to 0.08 N / m, and the tension fluctuation during spraying is within the median value ± 0.001 N / m. However, in the background, when performing the matting process by the spray method, if the surface tension of the spray liquid is too low, the particles become too large and irregular, and if the surface tension of the spray liquid is too high, the particles of the required size are too high. Is not obtained.

It is also necessary to measure and finely adjust the surface tension of the spray liquid when preparing the spray liquid for each lot. That is, the spray liquid is usually obtained by dissolving the resin in a solvent,
The surface tension may vary from lot to lot due to a weighing error of the material or the like. Therefore, the surface tension is measured for each lot,
Fine adjustment is preferred.

The temperature set value in the spray booth is set to 20 to
It has a median value in the range of 27 ° C, and the temperature fluctuation is ± 2
It is essential that the temperature be within ℃, but it is preferable to control the temperature close to room temperature from the viewpoint of energy efficiency. This is because it is very preferable in that the physical properties of the liquid, which are easily affected by temperature changes such as viscosity, are not changed with time.

When the humidity set value in the spray booth is 30 to
It has a median value within the range of 50%, and the humidity variation is ± 3
% Is essential, because it is very preferable in that the spraying from the spray booth and the drying of the droplets during scattering are always constant.

It is also necessary to control the intake and exhaust air humidity and air volume of the air conditioning in the booth. That is, the humidity in the spray booth can be kept constant by monitoring the air humidity of the intake and exhaust air circulating for air conditioning in the booth and adjusting the air volume.

The method for producing a photosensitive lithographic printing plate of the present invention comprises:
A method for producing a photosensitive lithographic printing plate that performs a matting process by a spray method, wherein a spray liquid in a spray booth to be used has at least an organic solvent and a resin, and the vapor pressure of the organic solvent has an explosive limit lower limit. And the vapor pressure has a median value in the range of 0.01 to 1% of the saturated vapor pressure of the organic solvent, and the fluctuation of the saturated vapor pressure during spraying is ± 0.005. %.

It is essential to set the vapor pressure of the organic solvent in the spray booth to be used as described above, in order to keep the drying of droplets during spraying and scattering always constant.

For this purpose, it is important to control the air intake and exhaust, air humidity, air volume, etc. of the air conditioning in the spray booth, and it is desirable that the inner wall of the spray booth is made of a solvent-resistant material and has good removability of the adhered resin. Are preferred. Specific examples include Teflon and SUS.

The method for producing a photosensitive lithographic printing plate according to the present invention is a method for producing a photosensitive lithographic printing plate in which a matting process is performed by a spray method. At least one of a means for capturing a part of the spray liquid and a means for repelling the spray liquid is provided between the printing plate and the printing plate.

The following is a description based on the drawings. FIG. 3 is a perspective view in which a means for capturing or repelling a part of the spray liquid is arranged between the spray device and the transfer target when performing the mat processing by the spray method.

That is, as means for capturing or repelling a part of the spray liquid between the spraying device 1 (spray gun in this case) and the photosensitive lithographic printing plate 4 as a transfer object, for example, an overspray catching plate 5 Is provided, unnecessary small particles in the spray droplet group can be removed, and coarse particles that can cause a failure can be similarly removed. Therefore, particles of a desired size can be efficiently adhered to the plate surface, and a good mat can be formed. In addition, the droplets that have jumped out of the spray device 1 to the outer peripheral portion are caught by the catching plate 5, and the inside of the spray booth is less likely to be contaminated.

FIG. 4 is a cross-sectional view showing an example of a use form of a normal spraying device. The positional relationship between the spraying device 1 and the photosensitive lithographic printing plate 4 conveyed by a pair of upper and lower rollers is shown. FIG. 5 is a cross-sectional view showing an example in which an overspray catching plate 5 is disposed as a means for catching or repelling a part of the mist liquid between the spraying device and the transfer-receiving member and performing mat processing. .

Originally, the spray droplets (mat particles) sprayed from the spray spraying device have a substantial spraying distance for those that have protruded to the outer peripheral portion, and the drying time during the scattering is long. In some cases, a suitable matte particle shape cannot be obtained, and therefore, it is necessary to set conditions for adhering to the photosensitive lithographic printing plate surface as accurately as possible. As a specific means for that purpose, for example, a potential opposite to each other is applied to each of the spray droplets sprayed from the spray atomizer and the capture plate. This makes it possible to catch the mat particles that have protruded to the outer peripheral portion of the printing plate. Specifically, as shown in FIG. 6, an electrode 6 is connected to the spraying device 1, and an electrode 6 ′ to which a potential different from that of the spraying device 1 is applied is connected to the capturing plate 5 of the overspray to spray the droplet. Is sprayed on the photosensitive lithographic printing plate 4. As a result, more excess liquid droplets can be collected.

As another means, an electric potential is applied to the spray droplets sprayed from the spray atomizer and the catching plate, and both are set to the same electric potential. Specifically, as shown in FIG. 7, the spray device 1 and the overspray catching plate 5 are connected to each other by an electrode 6 so as to have the same potential. As a result, the matte particles and the trapping plate 5 that have protruded to the outer peripheral portion of the photosensitive lithographic printing plate repel each other, and the traveling direction of the matte particles can be directed in the vertical direction of the printing plate surface, and thus has protruded to the outer peripheral portion of the printing plate. It becomes possible to apply the matting particles directly to the photosensitive lithographic printing plate.

The method for producing a photosensitive lithographic printing plate of the present invention comprises:
This is a method for producing a photosensitive lithographic printing plate that performs matting by a spray method, and electrically connects an overspray suction port provided on the back side of the photosensitive lithographic printing plate installed in a spray spraying device to be used. It is preferable to apply an electric potential so as to capture or repel a part of the spray droplet.

Hereinafter, description will be made with reference to the drawings. FIG. 8 is a perspective view showing an example of performing mat processing by a spray method while capturing overspray with a suction plate. The overspray suction plate 7 is disposed on the back side of the photosensitive lithographic printing plate 4.

In order to uniformly spray the entire surface of the printing plate conveyed in the form of a web, mat particles are usually sprayed over a wider area than the width of the photosensitive lithographic printing plate (hereinafter, referred to as the plate width). At this time, a group of mat particles that do not adhere to the photosensitive lithographic printing plate and scatter in a range wider than the plate width is called overspray. The overspray is sucked in by the suction port of the suction plate 7 provided on the back of the photosensitive lithographic printing plate being conveyed, and the contamination in the spray booth is suppressed. At this time, if the dispersion of the particle diameters of the sprayed droplet group is large, it is preferable that the droplets selectively reach the plate surface, and a potential opposite to that of the droplets is applied to the overspray suction port. By removing unnecessary small particles in the spray droplet group or by removing coarse particles that may cause a failure, droplets having a target particle diameter can be selectively caused to reach the plate surface. In addition, when the particle diameters of the sprayed droplet groups are uniform, it is more efficient and advantageous to direct overspray to the plate surface. By applying the same potential as the droplet to the suction port of the overspray, the overspray can be directed to the plate surface by causing the droplet to repel electrostatically from the suction port.

The method for producing a photosensitive lithographic printing plate according to the present invention comprises:
A method for producing a photosensitive lithographic printing plate that performs matting by a spray method, wherein the photosensitive lithographic printing plate installed in a spray atomizer is electrically grounded, and the absolute value of the potential of the inner wall of the spray booth is the aforementioned value. It is preferable that the absolute value is not less than the absolute value of the printing plate and not more than the absolute value of the spray droplet.

After the spray droplets fly out of the spray, they go to the plate surface not only by the inertial force but also by the electrostatic force generated by the potential difference between the spray droplets and the photosensitive lithographic printing plate. At this time, if the difference between the absolute value of the electric potential of the inner wall of the spray booth and the electric potential of the spray droplet is large, the adhesion of the liquid droplet to the inner wall of the spray booth by the electrostatic force increases, and the loss of the spray liquid increases. Also, if the absolute value of the potential of the inner wall of the spray booth and the potential difference between the photosensitive lithographic printing plate and the photosensitive lithographic printing plate are large, the mat particles adhered to the inner wall of the spray booth are liable to be scattered again by the electrostatic force and adhere to the photosensitive lithographic printing plate. Will easily contaminate the printing plate.

These problems can be suppressed to the minimum by setting the absolute value of the potential on the inner wall of the play booth to be larger than that of the photosensitive lithographic printing plate and not more than the spray droplet.

(Claims 36 to 38) The method for producing a photosensitive lithographic printing plate according to the present invention is characterized in that a surface of a photosensitive lithographic printing plate having a photosensitive layer on a support is subjected to a matting process by a spray method and then subjected to a plurality of processes. A method for producing a photosensitive lithographic printing plate by correcting the shape of a printing plate by applying a roller leveler having a book roller, wherein the tension of the photosensitive lithographic printing plate when passing through the roller leveler is 0.2 to 0. 0.7 kg / m ²
It is specified. When the tension is 0.2 kg / m ² or more, a sufficient correcting effect of the printing plate is obtained, and when the tension is 0.7 kg / m ^{2 or} less, the possibility that the mat particles are crushed or dropped is reduced. . Therefore, within this range, not only the printing plate is sufficiently corrected, but also the matte particles formed before the correction of the printing plate are firmly fixed on the photosensitive layer.

In a second method for producing the photosensitive lithographic printing plate of the present invention, a work roller constituting a roller leveler is coated with a material having a surface having a hardness lower than that of a resin forming a mat layer. Using
This is a method for producing a photosensitive lithographic printing plate by correcting the printing plate shape by the roller leveler.

If the surface hardness of the work roller is higher than the hardness of the resin forming the mat layer, the mat particles are crushed or fall off. Preferably, when the surface hardness of the work roller is not more than 3/4 of the hardness of the resin forming the mat layer, the effect is further improved. As the specific shape of the work roller, urethane rubber,
Those coated with natural rubber, styrene-butadiene rubber or the like are preferably employed.

Here, the roller leveler is a means for correcting a shape defect of a metal plate such as a steel plate, a stainless steel plate, and an aluminum plate. The roller leveler sandwiches the metal plate from above and below by a plurality of small-diameter rolls. By transporting the sheet while it is being bent, the surface of the metal plate is subjected to compositional deformation by repeated bending operations to reduce the internal stress of the metal plate and flatten it. What is a work roller?
It is a roller that directly contacts the object to be corrected among the rollers constituting the roller leveler and corrects the shape.

As a third method for producing a photosensitive lithographic printing plate according to the present invention, after a matting process is performed on the surface of the photosensitive layer by a spray method, a slip sheet is inserted between the photosensitive layer and the roller before the roller leveler is applied. The layers are layered and refined by a roller leveler. This method has an advantage that the slip sheet serves as a cushion layer, and does not cause the mat layer to collapse or fall off even when a conventional roller leveler is used.

Originally, when an interleaf paper is stacked in production or unpacked for use as a printing plate, the edge of the photosensitive lithographic printing plate comes into contact with the surface of the photosensitive layer of another lithographic printing plate, so that the surface of the photosensitive layer is exposed. The lithographic printing plate is provided on the photosensitive layer surface side of the lithographic printing plate, which has been subjected to mat processing, and is cut into a sheet together with the printing plate. Examples of the interleaving paper include polyethylene-laminated paper.

Next, materials, methods, and the like relating to the photosensitive lithographic printing plate usable in the present invention will be described below.

Support The support includes a plate having good dimensional stability and used as a plate material of a lithographic printing plate. An example of such a support is an aluminum support having a roughened surface. Examples of the surface roughening method include a method of mechanically roughening the surface, a method of electrochemically roughening the surface, a method of chemically roughening the surface with an alkali or acidic etching agent, and these. Can be used. The roughened aluminum support may be subjected to an anodic oxidation treatment and a sealing treatment if necessary, and a hydrophilic layer may be further provided. Further, a protective layer can be provided on the back surface of the support in order to prevent scratches on the photosensitive layer when the photosensitive printing plates are stacked and to prevent elution of aluminum into the developer during development.

Photosensitive Layer The photosensitive layer may be any one used as a photosensitive layer of a lithographic printing plate. For example, a positive photosensitive layer containing an o-quinonediazide compound as a photosensitive component, a photosensitive diazonium salt or a photosensitive diad compound may be used. Negative photosensitive layer having a compound having a photosensitive component as a photosensitive component, a photopolymerizable composition having a compound having an ethylenically unsaturated double bond capable of addition polymerization as a photosensitive component, photocrosslinkable containing cinnamic acid or dimethylmaleimide group A negative photosensitive layer containing a composition or the like as a photosensitive component is included. These photosensitive layers contain a photosensitive component and a binder resin as main components.

As the photosensitive component of the positive photosensitive layer, a resin obtained by polycondensing a polyphenol such as phenol, cresol and / or pyrogallol with an active carbonyl compound such as formalin or acetone is esterified with o-quinonediazidesulfonic acid. Or a polyhydroxy polynuclear compound such as polyhydroxybenzophenones or bisphenol esterified with o-naphthoquinonediazidosulfonic acid; as a binder resin, a resin obtained by polycondensing cresol and / or phenol with formalin (generally, a novolak resin) Is referred to as a preferred example.

Coating Method / Defect Inspection Means for coating the coating solution containing the above-described photosensitive layer composition on the support are not particularly limited, but a coating method combining rolls such as a double roll coater and a reverse roll coater, A wire bar coater, a die coater, or the like can be used.

At the time of coating the photosensitive layer, unexpected failure may occur due to adhesion of foreign substances to the support or entrapment of bubbles.
Significantly reduces the quality of the finished product. For this reason, the location where a failure has occurred is automatically detected during line conveyance. The detection of a failure is also performed by a contact type sensor, but it is preferable to use an optical type detector because abrasion is likely to occur on the surface of the photosensitive layer. At this time, it is needless to say that the light to be emitted from the sensor to the photosensitive layer should have a wavelength and energy that the photosensitive layer does not expose.

It is preferable that the failure point detection mechanism be performed at the stage of product completion, because a failure point generated in a process subsequent to the detection mechanism can also be detected. However, it is usually performed after the photosensitive layer is applied and before the mat processing. Since this is a process of providing irregularities by providing resin particles on the photosensitive layer irregularly in the mat processing, if a mechanism for detecting a failure location is provided after the mat processing, the failure portion and the mat particles provided properly are provided. This is because it is difficult to determine.

Mat Resin As a resin for forming a mat on the surface of the photosensitive layer, a resin soluble in an organic solvent or a resin soluble in water can be used.

As a resin for an organic solvent, a solution obtained by dissolving a resin soluble in an organic solvent in an organic solvent is sprayed on the surface of the photosensitive layer and dried to form a mat made of the resin. The resin to be formed is hardly soluble or insoluble in water,
And alkali-soluble resins.

As such a resin, for example, the following (a)
And copolymers containing monomer units formed from the monomers described in (c).

(A) The alkyl residue has 1 to 1 carbon atoms
At least one monomer selected from the group consisting of alkyl acrylates having 0 and alkyl methacrylates having 4 to 10 carbon atoms in the alkyl residue.

Specifically, methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, isoamyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, n-
Octyl acrylate, n-decyl acrylate, n-
Butyl methacrylate, isobutyl methacrylate, n
-Amyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, n-decyl methacrylate and the like.

(B) styrenes, acrylonitriles,
At least one monomer selected from the group consisting of acrylamides, methyl methacrylate and ethyl methacrylate.

Specifically, styrene, o- / m- / p-
Methylstyrene, 2,4-dimethylstyrene, 2,5-
Dimethylstyrene, 3,4-dimethylstyrene, 3,5
-Dimethylstyrene, 2,4,5-trimethylstyrene, 2,4,6-trimethylstyrene, o-ethylstyrene, 3,5-diethylstyrene, 2,4,5-triethylstyrene, pn-butylstyrene, m-sec-
Butylstyrene, m-tert-butylstyrene, p-
Hexylstyrene, pn-heptylstyrene, p-2
-Ethylhexylstyrene, p-fluorostyrene, o
-/ M- / p-chlorostyrene, 2-3-dichlorostyrene, 2,4-chlorostyrene, 2,5-dichlorostyrene, 2,6-dichlorostyrene, 3,4-dichlorostyrene, 2,5-difluoro Styrene, p-bromostyrene, p-cyanostyrene, p-hydroxystyrene,
m- / p-nitrostyrene, o-dimethylaminostyrene, acrylonitrile, α-chloroacrylonitrile,
α-bromoacrylonitrile, methacrylonitrile, methyl methacrylate, ethyl methacrylate, acrylamide, N-sec-butylacrylamide, N-te
rt-butylacrylamide, N, N-dibutylacrylamide and the like.

(C) at least one monomer selected from the group consisting of acrylic acid, methacrylic acid, maleic acid, itaconic acid, and alkali metal salts and ammonium salts thereof.

More specifically, acrylic acid, sodium acrylate, potassium acrylate, ammonium acrylate, methacrylic acid, sodium methacrylate, potassium methacrylate, ammonium methacrylate, maleic acid, sodium maleate, potassium maleate, maleate Ammonium itaconate, itaconic acid, sodium itaconate, potassium itaconate, ammonium itaconate, and the like.

The copolymerization ratio in the above copolymer is (a)
10-70% by mass, (b) 20-80% by mass and (c)
It is preferably from 6 to 50% by mass, and particularly preferably (a) 15
-50 mass%, (b) 40-70 mass% and (c) 10
２５25% by mass.

Further, in addition to the above (a) to (c), when a copolymer obtained by copolymerizing a monomer which can be crosslinked by heating such as N-methylolacrylamide is used, the copolymer is heated. And can be used as a resin for forming a mat. The introduction amount of this monomer is preferably from 10 to 80% by mass, particularly preferably 20% by mass.
６０60% by mass.

The resin adhered to the surface of the photosensitive layer may contain additives in addition to the above resins. Examples of the additives include fillers such as silicon dioxide, zinc oxide, titanium oxide, zirconium oxide, glass particles, alumina, and polymer particles (for example, particles of polymethyl methacrylate, polystyrene, phenol resin, and the like).

As the aqueous resin, a solution dissolved or dispersed in water is sprayed on the surface of the photosensitive layer and dried to form a mat made of the resin. Soluble or insoluble and alkali-soluble resins may be mentioned. Examples of such a resin include the resins described below.

Shellac (ordinary shellac), casein, alginic acid and salts of alginic acid such as ammonium and lower amine, maleic resin, water-soluble phenol resin, alkali-soluble alkylcellulose, alkali-soluble hydroxyalkylcellulose, polyvinyl alcohol (degree of saponification 70 mol) %), Water-soluble alkyd resin (such as alkyd resin solubilized with ammonia or volatile amine), water-soluble acrylic resin (such as acryl resin solubilized with volatile amine), gelatin, polyvinyl alcohol Or a combination of a water-soluble resin having a hydroxyl group such as a water-soluble cellulose-based resin and a curing agent such as dialdehyde or ethyleneimine, an N-methylolacrylamide polymer or a copolymer of N-methylolacrylamide with other monomers. Water-soluble thermally crosslinkable resin coalescing like.

Organic solvent Examples of the organic solvent for dissolving the organic solvent-soluble resin include:
Organic solvents having a boiling point of 75 to 250 ° C, for example (64.
7), ethanol (78.3), isopropyl alcohol (82.3), butanol (82.5-117.
7), ethyl acetate (77.1), acetone (56.
1), methyl ethyl ketone (79.6), toluene (1
11) and the like. Numerical values in parentheses represent boiling points (° C.).

Other organic solvents include n-hexane (68.7), cyclohexane (80) and heptane (9
8.4), hydrocarbons such as octane (125), nonane (151) and decane (74), diacetone alcohol,
3-methoxy-1-butanol, cyclohexanone (1
55.7), ethylene glycol (197), diethylene glycol (162), ethylene glycol monoacetate, ethylene glycol alkyl ethers and their acetates (methyl cellosolve, ethyl cellosolve,
Butyl cellosolve, ethylene glycol dimethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate), diethylene glycol monoalkyl ethers and their acetates (diethylene glycol monomethyl ether, diethylene glycol monomethyl ether acetate), diethylene glycol dialkyl ethers (diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, Diethylene glycol methyl ethyl ether), triethylene glycol alkyl ethers (monomethyl ether, monoethyl ether, dimethyl ether, diethyl ether, methyl ethyl ether), propylene glycol alkyl ethers and their acetates ( Nomethyl ether, monoethyl ether, n-propyl ether, monobutyl ether, monomethyl ether acetate, monoethyl ether acetate), dipropylene glycol alkyl ethers (dimethyl ether, diethyl ether), ethyl formate (53-54), propyl formate ( 81-82), amyl formate, methyl acetate (56.9), propyl acetate (10
1.6), butyl acetate, methyl propionate (79.
8), ethyl propionate, methyl butyrate, ethyl butyrate,
And the like, dimethylformamide, dimethylsulfoxide, dioxane, tetrahydrofuran, methyl lactate, ethyl lactate, methyl benzoate, ethyl benzoate, propylene carbonate and the like can also be used. In the present invention, a fast-drying organic solvent having a boiling point of 80 ° C. or less is preferable. Examples include methanol, ethanol, ethyl acetate, acetone, methyl ethyl ketone, n-hexane, cyclohexane, ethyl formate, methyl acetate, methyl propionate, and the like.

These organic solvents can be used alone or in combination of two or more. The concentration of the resin is preferably 5 to 40% by mass, more preferably 10 to 40% by mass.

Drying step and means The mat formed on the surface of the photosensitive layer by spray processing is
Dry if necessary. The drying means is not particularly limited, and includes a method of passing a printing plate through a high-temperature atmosphere for a certain period of time, a method of blowing high-temperature air, a method using convection or infrared light, and printing a heating roll directly from the back surface and / or the front surface. There is a method of contacting the plate. The drying conditions are not particularly limited because the optimum conditions are selected depending on the efficiency of the production process, the processing speed, and the like.
C., a relative humidity of 5 to 70%, and a processing time of 1 to 60 seconds are preferable, and a temperature of 60 to 90 ° C., a relative humidity of 10 to 20%, and a processing time of 5 to 20 seconds are more preferable.

JP-A-7-72632 and JP-A-7-3114
No. 58, No. 8-179510, and No. 8-179511, the drying conditions are described in JP-A-6-148875 and JP-A-6-3875.
No. 32155 describes the conditions of the drying means by hot-air spraying, and JP-A-6-202339 describes the conditions for drying in a high-temperature atmosphere. JP-A-7-175222 describes drying using a combination of convection and infrared rays. It is described.

In order to promote drying, the printing plate may be preheated immediately before forming the mat. The preheating means can be performed by the same means as the drying means. The preheating temperature is preferably from 50 to 200C, more preferably from 70 to 150C. When sufficient heat is applied, the mat droplets attached to the surface of the photosensitive layer are dried quickly, and may be sufficiently dried while being conveyed to the next step, so that the drying step is not necessarily required. JP-A-8-286380 discloses that the surface temperature of a photosensitive layer is 70 to 130 ° C. by using a heating roll from the back surface or by passing a printing plate through a heated atmosphere.
It is described that preheating is preferably performed at 75 to 90 ° C.

[0137]

EXAMPLES The present invention will now be described specifically with reference to examples, but the embodiments of the present invention are not limited thereto. In the following, "parts" represents "parts by mass".

(Claims 1 to 15) Example 1 Preparation of Aluminum Support Aluminum plate having a thickness of 0.24 mm (JIS 1050,
The refined H16) was immersed in a 100 g / l sodium hydroxide aqueous solution at 85 ° C for 1 minute to perform a degreasing treatment, and then subjected to a commercial alternating current having a current density of 80 A / dm ² in a 15 g / l hydrochloric acid aqueous solution at 25 ° C. Electrolytic surface roughening was performed for seconds. Then 5
After immersing in a 100 g / l sodium hydroxide aqueous solution at 0 ° C. for 10 seconds to perform a desmutting treatment,
Anodizing treatment was performed in g / l sulfuric acid with a direct current having a current density of 3 A / dm ² for 60 seconds. Oxide film amount is 20m
g / dm ² . Next, ammonium acetate 1 at 85 ° C.
After immersion treatment in 0 g / l for 30 seconds, drying was performed to obtain a support for a lithographic printing plate.

Subsequently, a coating solution of a photosensitive layer having the following composition was applied to the aluminum support and dried to form a photosensitive layer having a dry film thickness of 2 g / m ² .

Coating solution for photosensitive layer Novolak resin (phenol / m-cresol / p-cresol = 10/54/36 molar ratio, mass average molecular weight 4000) 7.5 parts pyrogallol acetone resin (weight average molecular weight 3000) and o- Condensate of naphthoquinonediazide-5-sulfonyl chloride (esterification rate 30%) 2.5 parts Victoria Pure Blue BOH (manufactured by Hodogaya Chemical Co., Ltd.) 0.08 parts 2,4-bis (trichloromethyl) -6- ( (p-methoxystyryl) -s-triazine 0.01 part Methyl ethyl ketone / propylene glycol monomethyl ether (40/60% by volume) 100 parts A resin solution having the following composition was applied to the surface of this photosensitive layer using a rotary spray electrostatic spray gun. After spraying under the following conditions, dry at 60 ° C for 5 seconds to provide a mat layer, To obtain a printing plate.

(Resin solution 1) Resin: methyl methacrylate / ethyl acrylate /
Acrylic acid = 50/30/20 (weight average molecular weight 150
00) Solvent: diethylene glycol dimethyl ether Solid content concentration: 30% by mass (Resin solution 2) Resin: methyl methacrylate / ethyl acrylate /
Acrylic acid = 50/30/20 (weight average molecular weight 150
00) water-soluble with diethylamine Solvent: water Solid content concentration: 20% by mass (mat processing conditions) Diameter of rotating bell: 30 mm Number of rotation of bell: 30,000 rpm Shaping air pressure: 80 kPa Applied voltage: -60 kV Liquid for mat processing Supply amount: 3 ml / min Distance between the tip of the spray gun and the photosensitive layer surface: 600 mm Transport speed of the photosensitive lithographic printing plate: 20 m / min Based on the above conditions, the diameter and height of the matte particles formed on the photosensitive layer surface Each condition was adjusted to prepare samples in which the number of particles was variously changed.

With respect to the photosensitive lithographic printing plate thus obtained, a metal blade having a width of 3 mm and a thickness of 0.5 mm, which is perpendicular to the surface of the photosensitive layer, was used to apply a load from above to the adhesiveness of the mat particles to the photosensitive layer. The surface of the photosensitive layer was slid while the mat was peeled off. The results are shown in Table 1 below.

[0143]

[Table 1]

Dp: average diameter of the contact surface with the plate surface h: average particle height σh: standard deviation of particle height / average particle height As is clear from the results in Table 1, Sample 3 has too large particle diameter. There are many failure points, the particle height is too high, the adhesive strength is weak, and burnout occurs during plate making. Sample 4 also has too many particle diameters and many failure points, the photosensitive layer is deteriorated by the solvent, It can be seen that the photosensitive layer remains in the non-image area, sample 5 has a high particle height for the particle diameter and low adhesion, and sample 6 has a low particle height and a long vacuum adhesion time. That is, (average particle height (μ
m)) ^5/2 × (amount of particles attached (g / m ² )) ^1/5 is 10 or less, such as 1.6, and the vacuum adhesion time is long.

The sample 7 has a large dimensionless standard deviation of the particle height, becomes a failure point when coarse particles are mixed in, and the number of fine particles increases, so that the vacuum adhesion time becomes longer. However, the area where the matte particles cover the photosensitive layer becomes large, the photosensitive layer cannot be effectively exposed at the time of exposure, and the non-image area remains, and the sample 9 has an insufficient amount of the matte particles and has a long vacuum adhesion time. I understand. That is, (average particle height (μm)) ^5/2 × (particle attached amount (g / m ² )) ^1/5 is 9.
Since it is 10 or less such as 2, the vacuum adhesion time is long.

Example 2 Next, processing conditions were adjusted so that the shape of the mat particles became the following conditions, and the number of particles, the amount of particles attached, and the area occupied by the mat particles were changed by changing the spray amount to prepare a sample. .

Diameter of contact surface with average plate surface: 12 to 18 μm Average particle height: 4 to 8 μm Dimensionless standard deviation of particle height: 0.30 to 0.45 Average particle height / average plate surface Contact surface diameter: 0.3 ~
0.5 The results are shown in Table 2 below.

[0148]

[Table 2]

As is evident from the results in Table 2, Sample 12
Is too small for the number of particles, the attached amount, and the occupied area, so that the vacuum adhesion time is long.For sample 13, the number of particles, the attached amount is excessive, and the area where the matte particles cover the photosensitive layer is large. Sample 14 has an excessive number of particles, an attached amount, and an occupied area, and the area where the matte particles cover the photosensitive layer becomes large, so that the photosensitive layer can be effectively exposed at the time of exposure. It can be seen that there is a residue in the non-image area.

Example 3 Next, as shown in Table 3 below, mat particles were prepared under various spray gun conditions, and the particle shapes were measured. The resin solution used was the above-mentioned resin solution 2. The results are shown in Table 3 below.

[0151]

[Table 3]

Θ °: angle between the vertical direction of the surface of the lithographic printing plate and the spraying direction As is clear from the results shown in Table 3, the particle shape of sample 16 becomes too large and the number of failure points increases, and sample 17 has a small particle shape. Sample 18 becomes too flat and the particle shape becomes too flat, so that the vacuum adhesion time becomes longer, the number of failure points increases, and Sample 19 has too high a particle height with respect to the particle diameter. Sample 20 has a low particle charge and few particles adhere to the plate surface. Particles are bonded to each other during scattering to become large particles and become a failure point. In Sample 22, the angle of the spray direction is perpendicular to the plate surface. It can be seen that, because of the large deviation from the above, the dispersion of the spray distance and the turbulence of the air flow occur, the size of the particles is not uniform, and a failure point is generated, which is not practical.

(Claims 16 to 28) Example 4 An aluminum plate having a thickness of 0.24 mm (JIS 1050,
The heat-treated H16) was immersed in a 100 g / L aqueous sodium hydroxide solution at 85 ° C. for 1 minute to perform a degreasing treatment, and then subjected to a commercial alternating current having a current density of 80 A / dm ² in a 15 g / L hydrochloric acid aqueous solution at 25 ° C. Electrolytic surface roughening was performed for seconds. Then 5
After immersing in a 100 g / L aqueous sodium hydroxide solution at 0 ° C. for 10 seconds to perform a desmutting treatment,
An anodizing treatment was performed for 60 seconds in a g / L sulfuric acid with a direct current having a current density of 3 A / dm ² . 20 mg of oxide film
/ Dm ² . Next, ammonium acetate 10 at 85 ° C.
After immersion in g / L for 30 seconds, drying was performed to obtain a support for a lithographic printing plate.

Subsequently, a coating solution of a photosensitive layer having the following composition was applied on the aluminum support and dried to form a photosensitive layer having a dry film thickness of 2 g / m ² .

(Coating solution of photosensitive layer) Novolak resin (phenol / m-cresol / p-cresol = 10/54/36 molar ratio, weight average molecular weight 4000) 7.5 parts pyrogallol acetone resin (weight average molecular weight 3000) and o Condensate of -naphthoquinonediazide-5-sulfonyl chloride (esterification rate 30%) 2.5 parts Victoria Pure Blue BOH (manufactured by Hodogaya Chemical Co., Ltd.) 0.08 parts 2,4-bis (trichloromethyl) -6 (P-methoxystyryl) -s-triazine 0.01 part Methyl ethyl ketone / propylene glycol monomethyl ether (40/60% by volume) 100 parts A resin solution having the following composition was applied to the surface of this photosensitive layer using a rotary spray electrostatic spray gun. After spraying under the following conditions, dry (60 ° C for 5 seconds) to provide a mat layer, To obtain a lithographic printing plate.

(Resin solution) Resin: methyl methacrylate / ethyl acrylate /
Acrylic acid = 50/30/20 (weight average molecular weight 150
00) Solvent: methyl ethyl ketone (boiling point 79.6 ° C.) Solid content concentration: 30% by mass (mat processing conditions) Diameter of rotating bell: 30 mm Number of rotation of bell: 30,000 rpm Shaping air pressure: 80 kPa Applied voltage: -60 kV Liquid for mat processing Supply amount: 3 ml / min Distance between the tip of the spray gun and the photosensitive layer surface: 600 mm Transport speed of the photosensitive lithographic printing plate: 20 m / min Spraying range of the above resin solution under the above processing conditions using the same apparatus as the apparatus shown in FIG. Was processed (sprayed) so as to be wider than the width of the photosensitive lithographic printing plate to be treated. The used capture plate was an endless belt whose surface was processed with Teflon, and the solvent pan for recovery was filled with the same methyl ethyl ketone as the solvent of the resin liquid so that the belt was immersed. The solvent in the recovered solvent pan is circulated by a liquid sending and discharging mechanism (not shown). The trapping plate pulled up from the recovery solvent pan is arranged so that the solvent adhering to the trapping plate is squeezed out by a nip roll (not shown). The catching plate may be an integral type, but the one shown is one on the left and right behind the printing plate.
And is movable in accordance with the width of the printing plate to be matted.

Hereinafter, description will be made with reference to the drawings. FIG. 9 is a perspective view of a diagram in which a spray device, a transfer receiving body, and a capturing plate for capturing a part of the spray liquid are arranged behind the spraying device, and a matting process is performed by a spray method. That is, an endless belt-like overspray is captured as a means for capturing a part of the spray liquid sprayed on the spray device 1 (in this case, a spray gun) and a region deviated from the photosensitive lithographic printing plate 4 as a transfer object. A plate 5 'is arranged, which is movable in the direction of travel of the printing plate. As a result, a uniform quality matting process can be performed uniformly in the width direction of the photosensitive lithographic printing plate, and the photosensitive lithographic printing plate is re-scattered by spray liquid particles attached to the photosensitive lithographic printing plate surface during spraying. Contamination can be prevented, unnecessary small particles can be removed, and coarse particles that can cause a failure can be removed as well. The recovery solvent pan 8 has the function described above.

As an evaluation, a sample subjected to mat processing by changing the position and the rotation speed of the illustrated capturing plate was prepared.
The distribution in the width direction was confirmed. The distribution is the printing plate (60
(cm width), the center and edges of the width were cut into 5 cm squares, and the amount of the mat was measured. The results obtained are shown below.

[0159]

[Table 4]

As is evident from Table 4, when a catching plate which moves in the direction of travel of the printing plate is provided, the amount of mat can be evenly distributed in the width direction of the photosensitive lithographic printing plate, and the printing is performed when spraying. It can be seen that the contamination of the printing plate due to the re-scattering of the mat particles attached to the plate surface tends to decrease. In particular, when the peripheral speed of the capturing plate is the same as the transport speed of the photosensitive lithographic printing plate, the effect is very excellent.

Example 5 A matting process was performed in the same manner as in Example 4 except that the apparatus was changed to the apparatus shown in FIG. That is, an overspray suction plate was used instead of the overspray capture plate. A sample subjected to mat processing was prepared by appropriately changing the position of the illustrated suction plate, and the distribution in the width direction was confirmed. The distribution was performed by cutting the center and the ends of the printing plate (60 cm width) after processing into 5 cm squares and measuring the amount of the mat attached. The results obtained are shown below.

[0162]

[Table 5]

As is clear from Table 5, when the suction plate is provided on the back side of the photosensitive lithographic printing plate, and the distance in the vertical direction of the plate surface is 30 mm or less, the amount of the mat applied to the photosensitive lithographic printing plate is reduced. It can be seen that the printing can be uniformly performed in the width direction, and that the contamination of the printing plate due to the re-scattering of the mat particles adhered to the printing plate surface during spraying tends to be reduced. In particular, when the suction plate has the same potential as the photosensitive lithographic printing plate, the effect is very excellent.

(Claims 29 to 35) Example 6 and Comparative Example 1 An aluminum plate having a thickness of 0.24 mm (JIS 1050,
The heat-treated H16) was immersed in a 100 g / L aqueous sodium hydroxide solution at 85 ° C. for 1 minute to perform a degreasing treatment, and then subjected to a commercial alternating current having a current density of 80 A / dm ² in a 15 g / L hydrochloric acid aqueous solution at 25 ° C. Electrolytic surface roughening was performed for seconds. Then 5
After immersing in a 100 g / L aqueous sodium hydroxide solution at 0 ° C. for 10 seconds to perform a desmutting treatment,
An anodizing treatment was performed for 60 seconds in a g / L sulfuric acid with a direct current having a current density of 3 A / dm ² . 20 mg of oxide film
/ Dm ² . Next, ammonium acetate 10 at 85 ° C.
After immersion in g / L for 30 seconds, drying was performed to obtain a support for a lithographic printing plate.

Subsequently, a coating solution of a photosensitive layer having the following composition was applied to the aluminum support and dried to form a photosensitive layer having a dry film thickness of 2 g / m ² .

(Coating solution of photosensitive layer) Novolak resin (phenol / m-cresol / p-cresol = 10/54/36 molar ratio, weight average molecular weight 4000) 7.5 parts pyrogallol acetone resin (weight average molecular weight 3000) and o Condensate of -naphthoquinonediazide-5-sulfonyl chloride (esterification ratio 30%) 2.5 parts Victoria Pure Blue BOH (manufactured by Hodogaya Chemical Co., Ltd.) 0.08 parts 2,4-bis (trichloromethyl) -6 (P-methoxystyryl) -s-triazine 0.01 part Methyl ethyl ketone / propylene glycol monomethyl ether (40/60% by volume) 100 parts A resin solution having the following composition was applied to the surface of this photosensitive layer using a rotary spray electrostatic spray gun. After spraying under the following conditions, drying was performed at 60 ° C. for 5 seconds to provide a mat layer. To obtain a printing plate.

(Resin solution 1) Resin: methyl methacrylate / ethyl acrylate /
Acrylic acid = 50/30/20 (weight average molecular weight 150
00) in water with diethylamine Solvent: water Solid content concentration: 20% by mass (resin solution 2) Resin: methyl methacrylate / ethyl acrylate /
Acrylic acid = 50/30/20 (weight average molecular weight 150
00) Solvent: diethylene glycol dimethyl ether (lower limit of explosion limit: 1.38 vol%) Solid content concentration: 30% by mass (mat processing conditions) Diameter of rotating bell: 30 mm Number of rotations of bell: 30,000 rpm Shaping air pressure: 80 kPa Applied voltage:- Supply of 60 kV matting liquid: 3 ml / min Distance between spray gun tip and photosensitive layer surface: 600 mm Transfer speed of photosensitive lithographic printing plate: 20 m / min Mat processing was performed using resin solution 1 under the above processing conditions. A printing plate was prepared, and the vacuum contact time was measured for each preparation time.

[0168]

[Table 6]

As is clear from Table 6, in Comparative Example 1 which is outside the scope of claim 1 of the present invention, the temperature of the spray liquid increases with time and the viscosity of the spray liquid increases, so that the droplet diameter increases. It can be seen that the vacuum contact time becomes short and a certain quality cannot be obtained. In addition, coarse mat particles began to be mixed in, resulting in defective printing plates having failure points.

Example 7 and Comparative Example 2 A printing plate subjected to mat processing using the resin solution 2 under the above-mentioned mat processing conditions was produced, and the vacuum adhesion time for each production time was measured.

[0171]

[Table 7]

As is clear from Table 7, in Comparative Example 2 which is out of the scope of claim 2 of the present invention, the saturated vapor pressure in the spray booth increases with the elapse of time, and the drying of the sprayed particles during scattering is reduced. The mat became flat on the delayed photosensitive layer, and the vacuum adhesion time became longer, so that a certain quality could not be obtained. In addition, the flat particles have too large an adhesion area with the photosensitive layer,
A defective product with a failure point occurred as a printing plate.

Examples 8 to 10 and Comparative Example 3 A printing plate was prepared by spraying using the conventional spraying method shown in FIG. 4 and the embodiments shown in FIGS. Note that the resin solution 2 was used as the spray liquid, and the applied voltage applied to the capture plate in FIG. 6 was +20 kv.

The vacuum contact time (s) at the width center and width edges of the obtained printing plate (1 m width), and the ratio of the height of the matte particles to the diameter of the surface where the particles contact the photosensitive layer were measured. Further, the amount attached to the printing plate was measured, and the spray efficiency with respect to the spray amount was calculated.

[0175]

[Table 8]

As is clear from Table 8, in Example 8, the particles whose (particle height / diameter of the photosensitive layer bonding surface) was increased at the end were removed, and the width distribution of the vacuum adhesion time was improved. You can see that it is.

Further, in Example 9, particles whose (particle height / diameter of photosensitive layer bonding surface) was increased at the end were removed, and the width distribution of the vacuum adhesion time was further improved as compared with Example 8. You can see that there is.

In Example 10, the particles whose edge (particle height / diameter of photosensitive layer bonding surface) was large changed the traveling direction to the front of the printing plate by the electric potential applied to the catching plate (opposite of spraying). It can be seen that the width distribution of the vacuum contact time has been improved. Further, since most of the particles can be directed to the plate surface, the spraying efficiency has been remarkably improved.

However, it can be seen that the width distribution of the vacuum contact time in Comparative Example 3 is extremely poor. That is, since there is an overspray whose spray range exceeds the width of the printing plate in order to perform a matting process on the entire width of the printing plate, the spray efficiency is limited.

Examples 11 to 13 and Comparative Example 4 The printing plate was continuously grounded, the voltage applied to the spray droplets (spray gun) was set to -60 kV under the aforementioned basic conditions, and the potential of the spray booth was as shown in Table 9 below. The matte processing was performed on the photosensitive lithographic printing plate while changing. The amount applied to the lithographic printing plate was measured, and the spray efficiency with respect to the spray amount was calculated.

[0181]

[Table 9]

*: In Comparative Example 4, a failure due to re-scattering from the printing plate occurred 6 hours after the start of spraying.

As is clear from Table 9, Examples 11 to 1
In No. 3, the spray efficiency is improved, and the spray booth is less likely to become dirty, so that there is no failure point due to re-scattering.

Examples 14 and 15 and Comparative Example 5 Next, using resin solution 2,
Matting was performed by applying a potential as shown in FIG. The spray efficiency and the particle size standard deviation were observed.

[0185]

[Table 10]

As is clear from Table 10, in Example 14 in which the potential opposite to that of the droplet was applied to the overspray suction port, the standard deviation of the particle diameter was smaller than that in Comparative Example 5, and the mat having the uniform particle diameter was obtained. It can be seen that the particles are selectively adhered to the plate. Further, in Example 15 in which an electrode having the same potential as the droplet was provided to the overspray suction port, a part of the overspray was also directed to the plate surface, and it can be seen that the spray efficiency was improved as compared with Comparative Example 5.

(Claims 36 to 38) Examples 16 to 18, Comparative Examples 6 and 7 A 0.24 mm thick aluminum plate (JIS 1050;
The refined H16) was immersed in a 100 g / l sodium hydroxide aqueous solution at 85 ° C for 1 minute to perform a degreasing treatment, and then subjected to a commercial alternating current having a current density of 80 A / dm ² in a 15 g / l hydrochloric acid aqueous solution at 25 ° C. Electrolytic surface roughening was performed for seconds. Then 5
After immersing in a 100 g / l sodium hydroxide aqueous solution at 0 ° C. for 10 seconds to perform a desmutting treatment,
Anodizing treatment was performed in g / l sulfuric acid with a direct current having a current density of 3 A / dm ² for 60 seconds. Oxide film amount is 20m
g / dm ² . Next, ammonium acetate 1 at 85 ° C.
After immersion treatment in 0 g / l for 30 seconds, drying was performed to obtain a support for a lithographic printing plate.

Subsequently, a photosensitive solution coating solution having the following composition was applied to the aluminum support and dried to form a photosensitive layer having a dry film thickness of 2 g / m ² .

(Coating solution of photosensitive layer) Novolak resin (phenol / m-cresol / p-cresol = 10/54/36 molar ratio, weight average molecular weight 4000) 7.5 parts pyrogallol acetone resin (weight average molecular weight 3000) and o Condensate of -naphthoquinonediazide-5-sulfonyl chloride (esterification ratio 30%) 2.5 parts Victoria Pure Blue BOH (manufactured by Hodogaya Chemical Co., Ltd.) 0.08 parts 2,4-bis (trichloromethyl) -6 (P-methoxystyryl) -s-triazine 0.01 part Methyl ethyl ketone / propylene glycol monomethyl ether (40/60% by volume) 100 parts A resin solution having the following composition was applied to the surface of the photosensitive layer using a rotary spray electrostatic spray gun. After spraying under the following conditions, drying was performed at 60 ° C. for 5 seconds to provide a mat layer. To obtain a printing plate.

(Resin solution) Resin: methyl methacrylate / ethyl acrylate /
Acrylic acid = 50/30/20 (weight average molecular weight 150
00) Solvent: diethylene glycol dimethyl ether (lower limit of explosion limit: 1.38 vol%) Solid content concentration: 30% by mass (mat processing conditions) Diameter of rotating bell: 30 mm Number of rotations of bell: 30,000 rpm Shaping air pressure: 80 kPa Applied voltage:- Supply amount of 60 kV matting liquid: 3 ml / min. Distance between the tip of the spray gun and the photosensitive layer surface: 600 mm. Transport speed of photosensitive lithographic printing plate: 20 m / min. After passing through, it was cut into 1030 mm x 800 mm.

(Evaluation) The curl of this photosensitive lithographic printing plate,
The crushing of the mat particles and the vacuum contact time were measured by electron microscope observation. In addition, any of the following two types of work rolls of the roller leveler was used. The results obtained are shown in Table 11 below.

Roller 1: Metal roll having an outer diameter of 50 mm Roller 2: Roll having a metal roll having an outer diameter of 30 mm lined with styrene-butadiene rubber and having an outer diameter of 50 mm (curl) The curl is vertical when suspended in the long side direction. Evaluation was based on the amount of floating from the surface. When the absolute value of the curl was 1 mm or less, it was evaluated as ○.

(Crushing of Matt Particles) 100 mat particles were visually observed with an electron microscope, and evaluated according to the following evaluation criteria.

... Less than 10 particles falling off, cracking and deforming.... 10 or more particles falling off, cracking and deforming. (Vacuum adhesion time) Use a film of 550 mm × 650 mm. Then, the vacuum adhesion was evaluated using a vacuum adhesion exposure machine manufactured by Dainippon Screen. The case of 50 seconds or less was regarded as good, and the case of longer than 50 seconds was regarded as bad.

[0195]

[Table 11]

As is evident from Table 11, when any of the methods for producing a photosensitive lithographic printing plate of the present invention is employed, the curl of the support is small and the shape of the printing plate becomes good. You can see that it has been corrected. Further, since the mat particles are not crushed and the vacuum adhesion time is sufficiently short, it can be seen that the mat particles are firmly fixed while maintaining the initial particle diameter. On the other hand, in the comparative example, the mat particles were crushed,
It can be seen that none of the curl corrections is satisfied at the same time. In particular, it has been found that when the mat particles are crushed or dropped, the vacuum adhesion time is adversely affected.

[0197]

According to a first aspect of the present invention, in a photosensitive lithographic printing plate having a mat formed on a plate surface by performing a mat process, the formed mat is vacuumed in a short time so as to be sufficiently applicable to a vacuum adhesion method. It has a remarkably excellent effect that it can be in close contact, has a necessary adhesive strength, does not contain a mat that causes a failure, and does not contain waste mat particles (particles deviating from the target size).

(Claims 16 to 35) According to the present invention, in a method of forming a mat by applying a mat process on a photosensitive lithographic printing plate by spraying, a mat process of a constant quality is performed and the mat is scattered during spraying. It has a remarkably excellent effect that high quality matting can be performed by removing unnecessary particles, loss of the spray liquid can be reduced, and contamination of the photosensitive lithographic printing plate due to re-scattering can be prevented.

(Claims 36 to 38) According to the present invention, in manufacturing a photosensitive lithographic printing plate, a system for correcting the shape of a printing plate by applying a roller leveler after a mat processing step to surely correct the shape of the printing plate. While the matting process is performed, the matting particles formed in the matting process do not collapse or fall off.

[Brief description of the drawings]

FIG. 1 is a perspective view of spray particles scattered from an electrostatic spray gun.

FIG. 2 is a schematic diagram illustrating an example of a process of applying a matting process to a printing plate surface using an electrostatic spray gun as viewed from above.

FIG. 3 is a perspective view in which a catching plate is arranged between a spraying device and a transfer object to perform mat processing.

FIG. 4 is a cross-sectional view showing an example of a usage form of a normal spraying device.

FIG. 5 is a cross-sectional view showing an example in which a catch plate is arranged between the spraying device and the transfer target to perform mat processing.

FIG. 6 is a cross-sectional view showing an example in which a matting process is performed while applying an electric potential to the capturing plate to capture overspray.

FIG. 7 is a cross-sectional view showing an example in which a matting process is performed while applying an electric potential to the capturing plate and capturing overspray.

FIG. 8 is a perspective view showing an example of performing mat processing while capturing overspray with a suction plate.

FIG. 9 is a perspective view showing an example of performing mat processing while capturing overspray by a capture plate.

[Explanation of symbols]

 Reference Signs List 1 electrostatic spray gun (spray device) 2 bell 3 spray particles 4 photosensitive lithographic printing plate 5, 5 'overspray catching plate 6, 6' electrode 7 overspray suction plate 8 recovery solvent pan

Claims (38)

[Claims] 1. A photosensitive lithographic printing plate having a photosensitive layer on a support, wherein the surface of the photosensitive layer is matted,
Non-dimensional standard of particle height obtained by dividing the average contact surface of the formed mat particles with the plate surface by 4 to 50 μm, average particle height by 2 to 20 μm, and standard deviation of particle height by average particle height A photosensitive lithographic printing plate having a deviation of 0.7 or less. 2. The average particle diameter of the contact surface of the mat particles with the plate surface is 10 to 20 μm, and the average particle height is 2 to 1 μm.
2. The photosensitive lithographic printing plate according to claim 1, wherein the dimensionless standard deviation of the particle height obtained by dividing the standard deviation of the particle height by the average particle height is 0.5 μm or less. 3. A photosensitive lithographic printing plate having a photosensitive layer on a support, wherein the surface of the photosensitive layer is matted,
The average diameter of the contact surface of the formed mat particles with the plate surface is 4 to 50 μm, the average particle height is 2 to 20 μm, and (average particle height) / (average diameter of the contact surface with the plate surface) is 0. Two
A photosensitive lithographic printing plate, wherein the ratio is 0.7. 4. The average particle diameter of the contact surface of the mat particles with the plate surface is 10 to 20 μm, and the average particle height is 2 to 1 μm.
4. The photosensitive lithographic printing plate according to claim 3, wherein the average lithographic printing plate has a particle diameter of 0 to 0.3 μm, and (average particle height) / (average diameter of the contact surface with the plate surface) is 0.3 to 0.6. 5. The photosensitive lithographic printing method according to claim 3, wherein the dimensionless standard deviation of the particle height obtained by dividing the standard deviation of the particle height by the average particle height is 0.7 or less. Edition. 6. A photosensitive lithographic printing plate having a photosensitive layer on a support, wherein the surface of the photosensitive layer is matted,
The average number of particles of the formed mat particles having a contact surface with the plate surface of 4 to 50 μm, the average particle height of 2 to 20 μm, and the diameter of the contact surface with the plate surface having a failure point of 100 μm or more is the total number of particles. A photosensitive lithographic printing plate characterized in that the content is 1% or less. 7. The photosensitive lithographic printing plate according to claim 1, wherein the matting particles satisfy the following expression. (Average particle height (μm)) ^5/2 × (Amount with particles (g /
m ² )) ^1/5 > 10 8. A photosensitive lithographic printing plate having a photosensitive layer on a support, wherein the surface of the photosensitive layer is matted.
A photosensitive lithographic plate wherein the formed matting particles have an average contact surface diameter with the plate surface of 4 to 50 μm, the average particle height is 2 to 20 μm, and the matting particles satisfy the following formula: Print version. (Average particle height (μm)) ^5/2 × (Amount with particles (g /
m ² )) ^1/5 > 10 9. The photosensitive lithographic printing plate according to claim 1, wherein the number of the mat particles is 10 to 1000 particles / mm ² . 10. The coating amount of the mat particles is 0.005.
10 to 0.5 g / m ^2.
The photosensitive lithographic printing plate according to any one of the above items. 11. The photosensitive lithographic printing plate according to claim 1, wherein an area occupied by the matting particles on the surface of the photosensitive layer is 0.3 to 50%. 12. The method according to claim 1, wherein the matting of the surface of the photosensitive layer is performed by electrostatic spraying.
2. The photosensitive lithographic printing plate according to claim 1. 13. In the electrostatic spraying, the outer peripheral speed of the bell is 10 to 120 m / sec, the distance from the spray position to the plate surface to be sprayed is 200 to 800 mm, and the applied voltage of the bell is -10 to -100 kV. The photosensitive lithographic printing plate according to claim 12, wherein: 14. The electrostatic spraying process according to claim 12, wherein the angle between the spraying direction and the vertical direction of the photosensitive printing plate surface as the object to be sprayed is 10 degrees or less. Photosensitive lithographic printing plate. 15. The method according to claim 1, wherein the mat particles are obtained by spraying a liquid formed by dissolving or dispersing a resin in an organic solvent, or both. The photosensitive lithographic printing plate described in the above. 16. A method for producing a photosensitive lithographic printing plate, wherein a surface of a photosensitive lithographic printing plate having a photosensitive layer on a support is subjected to a matting process by a spray method, wherein a spraying range of a spray used is a photosensitive lithographic printing plate. Is set wider than the width of the plate, the particles sprayed off the plate surface are captured by capture plates provided outside both sides in the conveying direction of the photosensitive lithographic printing plate, and the capture plate is the photosensitive lithographic plate. A method for producing a photosensitive lithographic printing plate, characterized in that the lithographic printing plate moves in the traveling direction of the printing plate. 17. The method for producing a photosensitive lithographic printing plate according to claim 16, wherein the moving speed of the capturing plate is the same as the transport speed of the printing plate. 18. The method for producing a photosensitive lithographic printing plate according to claim 16, wherein the capturing plate has a belt shape. 19. A spray liquid sprayed from the spray is a liquid formed by dissolving and / or dispersing a mat particle component in an organic solvent, or both, and a spray liquid particle component captured by a capture plate. The method for producing a photosensitive lithographic printing plate according to any one of claims 16 to 18, wherein the compound is dissolved and removed with an organic solvent used as a solvent for the spray liquid, and then used again as a spray liquid. 20. The method for producing a photosensitive lithographic printing plate according to claim 19, wherein the boiling point of the organic solvent for dissolving the spray liquid particle components captured by the capturing plate is 80 ° C. or less. 21. The capture plate is on the back side of a photosensitive lithographic printing plate, the distance between the capture plate and the photosensitive lithographic printing plate in the plate vertical direction is 5 to 50 mm, and the capture plate is a photosensitive lithographic printing plate. The method for producing a photosensitive lithographic printing plate according to any one of claims 16 to 20, wherein the lithographic printing plate is provided so as to overlap in the width direction of the lithographic printing plate. 22. The method according to claim 16, wherein the method of performing the matting by a spray method is an electrostatic spray method, and the capturing plate has the same potential as a photosensitive lithographic printing plate.
22. The method for producing a photosensitive lithographic printing plate according to any one of 21. 23. A method for producing a photosensitive lithographic printing plate, in which a surface of a photosensitive lithographic printing plate having a photosensitive layer on a support is subjected to a matting process by a spray method, wherein a spraying range of a spray used is a photosensitive lithographic printing plate. Is set wider than the plate width, the particles sprayed off the plate surface are captured by a suction plate having suction ports provided outside both sides in the conveying direction of the photosensitive lithographic printing plate, and the suction plate A method for producing a photosensitive lithographic printing plate, wherein the distance of the photosensitive lithographic printing plate in the plate surface vertical direction is 30 mm or less. 24. The photosensitive lithographic printing plate according to claim 23, wherein the matting process by the spraying method is an electrostatic spraying method, and the suction plate has the same potential as the photosensitive lithographic printing plate. Manufacturing method. 25. A spray gun used for a spray method swings in the width direction of the photosensitive lithographic printing plate, changes the angle from the plate surface vertical direction of the photosensitive lithographic printing plate to the width direction, or The method for producing a photosensitive lithographic printing plate according to any one of claims 16 to 24, wherein both of the steps are performed so that the spray range of the spray is wider than the plate width of the photosensitive lithographic printing plate. 26. At least one of a swing speed of the spray gun in the width direction of the photosensitive lithographic printing plate and an angle changing speed from the plate surface vertical direction to the width direction is equal to or higher than the transport speed of the lithographic printing plate. The method for producing a photosensitive lithographic printing plate according to claim 25, wherein: 27. A method for producing a photosensitive lithographic printing plate in which a surface of a photosensitive lithographic printing plate having a photosensitive layer on a support is subjected to a matting process by a spray method according to a width of the photosensitive lithographic printing plate to be processed. And changing the position of the side wall of the spray chamber. 28. The photosensitive lithographic printing plate according to claim 16, wherein the position of the side wall of the spray chamber is changed according to the plate width of the photosensitive lithographic printing plate to be processed. Production method. 29. A method for producing a photosensitive lithographic printing plate, in which a surface of a photosensitive lithographic printing plate having a photosensitive layer on a support is subjected to a matting process by a spray method, wherein a temperature of a spray liquid from a spray booth to be used is 20. A median value in the range of ~ 27 ° C, a temperature variation during spraying within ± 2 ° C of the median value, a viscosity having a median value in the range of 5-200 mPa · s, and a viscosity variation during spraying. Is within the median value ± 2 mPa · s, the surface tension has a median value in the range of 0.02 to 0.08 N / m, and the tension fluctuation during spraying is the median value ± 0.001 N
/ M, and the temperature setting value of the spray liquid in the spray booth has a median value in the range of 20 to 27 ° C, the temperature fluctuation is within the median value ± 2 ° C, and the humidity setting value is 30 to 50
%, And a method for producing a photosensitive lithographic printing plate having a median value within a range of ± 3% and a humidity variation within ± 3%. 30. A spray liquid in a spray booth to be used contains at least an organic solvent and a resin, the vapor pressure of the organic solvent is not more than 1/2 of the lower limit of explosion limit, and the vapor pressure is not more than the organic pressure. It has a median value in the range of 0.01 to 1% of the saturated vapor pressure of the solvent, and the variation of the saturated vapor pressure during spraying is ±
30. The method for producing a photosensitive lithographic printing plate according to claim 29, wherein the content is 0.005% or less. 31. A method for producing a photosensitive lithographic printing plate, wherein a surface of a photosensitive lithographic printing plate having a photosensitive layer on a support is subjected to a matting process by a spray method, wherein a spray liquid in a spray booth to be used contains at least an organic solvent. And the resin has a vapor pressure of 1/2 of the lower limit of the explosion limit.
Or less, and the vapor pressure has a median value in the range of 0.01 to 1% of the saturated vapor pressure of the organic solvent, and the fluctuation of the saturated vapor pressure during spraying is within ± 0.005% of the median value. A method for producing a photosensitive lithographic printing plate. 32. A method for producing a photosensitive lithographic printing plate in which a surface of a photosensitive lithographic printing plate having a photosensitive layer on a support is subjected to a matting process by a spray method, between a spray atomizing apparatus used and the printing plate. A process for capturing or repelling a part of the spray liquid. 33. The spray method is an electrostatic spray method, and an electric potential is applied to a means provided between the spray atomizer and the printing plate for capturing or repelling a part of spray droplets. The method for producing a photosensitive lithographic printing plate according to claim 32, wherein the method is operated. 34. The spraying method is an electrostatic spraying method, and electrically sprays droplets onto an overspray suction port provided on the back side of a photosensitive lithographic printing plate installed in the spray spraying device. The method for producing a photosensitive lithographic printing plate according to claim 32, wherein an electric potential is applied so as to capture or repel a part of the lithographic printing plate. 35. The photosensitive lithographic printing plate installed in the spray atomizer is electrically grounded, and the absolute value of the potential of the inner wall of the spray booth is equal to or more than the absolute value of the printing plate and equal to or less than the absolute value of the spray droplet. 35. The method for producing a photosensitive lithographic printing plate according to claim 33, wherein: 36. A photosensitive lithographic printing plate having a photosensitive layer on a support, which is subjected to a matting process by a spray method, and then subjected to a roller leveler for correcting the printing plate shape using a plurality of rollers. A method for producing a photosensitive lithographic printing plate, wherein the tension of the photosensitive lithographic printing plate when passing through the roller leveler is 0.2 to 0.7 kg / m ² . 37. A photosensitive lithographic printing plate having a photosensitive layer on a support, which is subjected to a matting process by a spray method and then subjected to a roller leveler for correcting the shape of the printing plate using a plurality of rollers. A method for producing a photosensitive lithographic printing plate, characterized in that the surface of the roller in direct contact with the photosensitive lithographic printing plate is coated with a material having a hardness lower than the hardness of the material forming the mat layer. Plate production method. 38. A photosensitive lithographic printing plate having a photosensitive layer on a support, which is subjected to a matting process by a spray method, and then subjected to a roller leveler for correcting the printing plate shape using a plurality of rollers. A method for producing a photosensitive lithographic printing plate, comprising: laying a slip sheet between a surface provided with a photosensitive layer and the roller to correct the shape of the printing plate.