JP2002210913A - Wetting water supplier and printing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wetting water supplier and a printing device, which are capable of supplying wetting water while changing the wetting water in accordance with an image on a printing plate. SOLUTION: A wetting water supplying unit 11 is constituted of an ink jet head 20 consisting of the group of a plurality of discharging elements arranged along the axial line of the plate cylinder 1. In this printing device, image data for supplying the wetting water is operated based on the image data corresponding to the image on the printing plate. The image data for supplying wetting water are obtained by converting the concentration of ink image simultaneously with the converting of resolution of the image data and the data show the image concentration of the wetting water. Respective image concentrations of image data for supplying the wetting water are changed into area gradation by error dispersion method or dither method whereby the wetting water discharging position of the discharging elements on the printing plate are determined. In this wetting water supplying unit 11, the amount of wetting water can be changed with respect to the axial direction of the plate cylinder or the rotating direction of the plate cylinder whereby the optimum amount of wetting water can be retained in each area of surface of the printing plate and, as a result, the quality of the printing can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dampening solution supply device for supplying dampening solution to a printing plate, and a printing apparatus including the dampening solution supply device.

[0002]

2. Description of the Related Art In offset printing, dampening water is supplied to a non-image area, which is hydrophilic, on a printing plate, and ink is supplied to an image area, which is lipophilic, to form an ink on the printing plate. An image is formed, and the ink image is transferred onto printing paper via a blanket or the like. For this reason, the lithographic printing apparatus is provided with a dampening solution supply device for supplying dampening solution onto the printing plate. As the dampening water supply device, a method of uniformly applying dampening water with a dampening roller and a method of spraying dampening water from a plurality of spray nozzles are generally used. For example, in the case of the latter,
There is a technique described in Japanese Patent No. 0009. In the technique disclosed in the above publication, the dampening solution amount is varied in accordance with the printing speed of the printing apparatus, but the dampening solution is uniformly applied to the printing plate surface.

[0003]

In general offset printing, when the amount of dampening solution is insufficient, ink is applied to a portion where ink does not need to be applied, that is, a phenomenon called "ink entanglement" occurs. This is not desirable in print quality. Also, if the amount of dampening water is too large, the print density will decrease,
When dried, a so-called "water-filled" phenomenon occurs, which results in a clear halftone dot, which is also undesirable. Therefore, in the conventional offset printing, it is necessary to appropriately adjust the amount of dampening solution.

However, in the image area of the printing plate surface, the ratio of the image area / non-image area (image area or image density) differs for each area, and the amount of fountain solution consumed differs in each area. In particular, if the image area ratio of each area on the printing plate surface is largely different, it is difficult to adjust an appropriate amount of dampening solution, and even if a uniform amount of dampening solution is supplied on the printing plate surface, Each time there is a possibility that the amount of dampening water will be excessive or insufficient.

The present invention has been made in order to solve the above-mentioned problems, and has been made to solve the above-mentioned problems, and has a dampening solution supply device for supplying a variable amount of dampening solution for each predetermined area on a printing plate, and the dampening solution. Providing a printing device with a supply device,
In particular, the dampening solution can be varied not only in the axial direction of the plate cylinder but also in the rotational direction of the plate cylinder as the variable direction of the dampening solution, so that the two-dimensional dampening water amount can be varied according to the image area on the printing plate surface. An object of the present invention is to provide a supply device and a printing device provided with the dampening solution supply device.

[0006]

According to a first aspect of the present invention, there is provided a dampening solution supply device for supplying a dampening solution to a printing plate provided on a peripheral surface of a plate cylinder, wherein the dampening solution supply device includes a printing plate. A plurality of dampening solution discharging means capable of discharging dampening water independently to the printing plate surface, and a dampening water discharge amount discharged from each dampening water discharging means. And control means for performing time-series control along the rotation direction of the plate cylinder.

According to a second aspect of the present invention, in the fountain solution supply device according to the first aspect, the fountain solution discharging means is capable of discharging the fountain solution drop by drop onto the printing plate surface. It is characterized by an ink jet head type.

According to a third aspect of the present invention, there is provided the dampening solution supply device according to the first or second aspect, wherein the dampening solution is supplied based on image data corresponding to an image on the printing plate. The dampening water supply image data is calculated, and the dampening water amount is controlled using the dampening water supply image data.

According to a fourth aspect of the present invention, there is provided a dampening solution supply device according to any one of the first to third aspects, wherein dampening solution discharged by the dampening solution discharging means is leveled on a printing plate surface. And a leveling roller for performing the operation.

According to a fifth aspect of the present invention, there is provided a dampening solution supply device for supplying dampening solution to a printing plate surface provided on a peripheral surface of a plate cylinder, wherein the dampening solution is supplied to a printing plate surface in a substantially uniform manner. A first dampening solution supply means for supplying a dampening solution, and a second dampening solution supply means for selectively supplying a dampening solution to a desired position on the printing plate surface. The amount of dampening water according to the image on the printing plate surface is supplied by the sum of the amount of dampening water by the first dampening water supply unit and the amount of dampening water by the second dampening water supply unit.

According to a sixth aspect of the present invention, there is provided the dampening solution supply device according to the fifth aspect, wherein the second dampening solution supply means is arranged along an axial direction of the plate cylinder, and A plurality of dampening solution discharge means capable of discharging dampening water independently to the plate surface, and the dampening water discharge amount discharged from the dampening water discharging means in the plate cylinder axis direction and the plate cylinder. And control means for controlling the rotation direction.

According to a seventh aspect of the present invention, there is provided the dampening solution supply device according to the sixth aspect, wherein the dampening solution is supplied based on image data corresponding to an image on the printing plate. The dampening water supply image data is calculated, and the dampening water image density of the dampening water supply image data exceeds the dampening water image density corresponding to the specified amount of the first dampening water supply means, An additional dampening solution is supplied from the second dampening solution supply means.

According to the present invention, there is provided a printing apparatus which performs printing by supplying dampening water and ink to a printing plate mounted on a plate cylinder and transferring an ink image on the printing plate surface to printing paper. Providing a dampening solution discharge head in which a plurality of discharge elements are arranged along the axial direction of the plate cylinder, and varying a dampening solution discharge amount discharged from each discharge element with rotation of the plate cylinder to change a printing plate surface. The fountain solution amount is variably supplied two-dimensionally to the desired portion above.

According to a ninth aspect of the present invention, there is provided the printing apparatus according to the eighth aspect, wherein image data for supplying dampening water is created from image data corresponding to an image on a printing plate. Control means for controlling so as to selectively discharge dampening water from the plurality of discharge elements based on the dampening water supply image data.

According to a tenth aspect of the present invention, there is provided the printing apparatus according to the ninth aspect, further comprising image recording means for recording an image on a printing plate held on a plate cylinder based on the image data. It is characterized by having.

According to an eleventh aspect of the present invention, in the printing apparatus according to the tenth aspect, the resolution of the dampening solution discharge head is lower than the resolution of the printing plate recording means.

According to a twelfth aspect of the present invention, in the printing apparatus according to any one of the eighth to eleventh aspects, another fountain solution supply means for supplying the fountain solution substantially uniformly to the printing plate surface is provided. It is characterized by being attached.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] A first embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic side view showing an example of a printing apparatus provided with a dampening water supply device according to the present invention. In the figure, the printing device is:
A plate cylinder 1 for holding a printing plate, a blanket cylinder 2 in contact with the plate cylinder 1, an impression cylinder 3 in contact with the blanket cylinder 2, a feed cylinder 4 for feeding printing paper to the impression cylinder 3, and A discharge cylinder 5 for receiving printing paper from the impression cylinder 3 and a paper supply cylinder 4
A paper supply unit 6 for supplying print paper to the paper cylinder, a paper discharge unit 7 for discharging print paper from the paper discharge cylinder 5, a plate supply / discharge unit 8 for supplying or discharging a printing plate to or from the plate cylinder 1, An image recording unit 9 for recording an image on the printing plate on the plate cylinder 1, a developing unit 10 for developing the printing plate on which the image is recorded, a dampening water supply unit 11 for supplying dampening water to the printing plate, An ink supply unit 12 for supplying ink to the printing plate; and a control unit 13 for controlling each unit of the printing apparatus.

The plate cylinder 1 has a peripheral surface on which a printing plate for two colors of different colors can be mounted on its peripheral surface, and the peripheral surface is provided with a gripping means (not shown) for mounting the printing plate. This plate cylinder 1
During printing, the other cylinders 2 to 5 are driven by a printing motor (not shown).
The plate is configured to be rotated in common with a plate making motor (not shown) during plate making, and provided with clutch means (not shown) for selectively transmitting drive from both motors. ing.

The blanket cylinder 2 has the same diameter as the plate cylinder 1,
A blanket for two colors is provided on the peripheral surface. The blanket cylinder 2 is configured to rotate in contact with the plate cylinder 1 during printing and to transfer two color ink images from the printing plate on the plate cylinder 1.

The impression cylinder 3 includes the plate cylinder 1 and the blanket cylinder 2.
And the peripheral surface thereof is provided with a gripper capable of mounting one sheet of printing paper. The impression cylinder 3 rotates in contact with the blanket cylinder 2 during printing.
It is possible to overprint two different colors of ink images on the printing paper by rotating twice while rotating once.

Each of the paper feed cylinder 4 and the paper discharge cylinder 5 has the same diameter as that of the impression cylinder, and is provided with a gripper capable of transferring printing paper to and from the impression cylinder. In this printing apparatus, since the printing paper is supplied and discharged every two rotations of the impression cylinder, the paper supply cylinder 4 and the discharge cylinder 5 transfer the printing paper to the impression cylinder 3 every two rotations. Will be

The paper feeding unit 6 is a paper feeding device that takes out printing paper one by one from a pile on which sheet-shaped printing paper is stacked and supplies the printing paper to the paper feeding cylinder. One print sheet is supplied for every two rotations of 4. Similarly, the paper discharge unit 7 is a device that receives the print paper from the paper discharge cylinder 5 and sequentially discharges the print paper onto a pile, and receives one print paper every two rotations of the paper discharge cylinder 5 to discharge the paper. Do.

The plate supply / discharge unit 8 is a device that stores unused sheet-shaped printing plates and supplies them to the plate cylinder 1, and peels off used printing plates from the plate cylinder 1 and stores them again. In the present embodiment, two independent printing plates capable of recording an image for one color are held on the plate cylinder 1, but a continuous printing plate capable of recording an image area for two colors is provided. One of the printing plates may be held on the plate cylinder 1. Further, as the plate supply / discharge unit 8, a roll-shaped printing plate may be appropriately cut and mounted on the printing plate. Further, a printing plate in the form of a roll may be built in the plate cylinder, and the printing plate may be fed out to the peripheral surface of the plate cylinder 1 by a necessary amount.

The image recording unit 9 is a device for recording an image on a printing plate held on the plate cylinder 1. In the present embodiment, an image is recorded on a printing plate of a silver halide photosensitive material by laser exposure. I do. The image recording unit 9 has an exposure head provided with a plurality of laser irradiators arranged along the axial direction of the plate cylinder, and each laser irradiator has a binary image obtained by RIP processing the original image data. On / off control is performed for each pixel (dot) based on the image data. In accordance with the exposure, the plate cylinder 1 is rotated by the plate making motor, and the exposure head is moved in the axial direction of the plate cylinder to record an image on the printing plate.

According to the present invention, even in a positive type printing plate in which a portion exposed based on the image data becomes a hydrophilic non-image portion, on the contrary, the exposed portion becomes a lipophilic image portion. However, the present invention can be applied to a negative type printing plate. In the present embodiment, the image recording unit 9 records an image by laser exposure, but performs plate making by other image recording methods such as heat melting, thermal transfer, laser processing, ablation processing, electric discharge processing, and ink jet plate making. It may be something.

The developing unit 10 is a device for performing a developing process on a printing plate on which an image is recorded by the laser exposure, and is configured to sequentially apply a processing liquid such as a developing solution to the printing plate. I have. Note that if the image recording unit 9 is an image recording method that records an image by heat melting, thermal transfer, laser processing, ablation processing, electric discharge processing, or the like, and does not require development processing on a silver halide photosensitive material,
The developing unit 10 is unnecessary.

The dampening water supply unit 11 will be described with reference to FIG. FIG. 2 is an explanatory diagram showing the correspondence between the plate cylinder 1 and the dampening solution supply unit 11. In the figure, dampening water supply unit 11
Is an ink jet head 20 composed of a plurality of ejection elements arranged along the axial direction of the plate cylinder 1 (the left-right direction in FIG. 2); The inkjet head 20 includes a movable leveling roller 21, and the drawing resolution of the inkjet head 20 may be lower than that of the image recording unit 9.

In the specification of the present application, the ink jet head 20 is used for discharging dampening water, and does not discharge ink (ink) itself. However, it is referred to as an ink jet head for easy understanding in general terms. ing. In addition, the ink jet head 20 uses a fountain solution in units of one drop (1 drop).
As long as it can be ejected in pixel units, any type such as a piezo drive type or a thermal drive type can be used. Further, the inkjet head 20 may be capable of changing the discharge amount of one drop of dampening water at an intermediate gradation.

In this embodiment, the ink-jet heads 20 are arranged along the plate cylinder axial direction so as to cover the width of the printing plate P. However, as long as the inkjet heads 20 to be used are short, a plurality of inkjet heads 20 may be connected in series or in a staggered manner so as to extend to the width of the printing plate P.
Further, a plurality of inkjet heads 20 may be arranged in parallel along the plate cylinder axis direction, and the respective inkjet heads may be controlled in association with each other.

The ink jet head 20 is arranged so that dampening water is supplied from a common dampening water storage tank 22. The dampening water storage tank 22 stores water itself or water to which various chemicals such as alcohol and preservatives are added as dampening water, and circulates, adjusts the temperature, if necessary.
A mechanism for performing filtration, addition adjustment of various chemicals, and the like is provided.

Returning to FIG. 1, the two ink supply means 12
Is a device for supplying inks of different colors to the corresponding printing plates on the plate cylinder 1, and comprises a general ink fountain means and a plurality of ink rollers for kneading and transmitting the ink. The final inking roller of the ink roller is provided with elevating means by a cam mechanism (not shown) so as to selectively contact the printing plate on the plate cylinder.

The control section 13 is a computer system electrically connected as control means for controlling each section of the printing apparatus including the dampening solution supply section 11, and includes various input means, storage means, display means and the like. Prepare. The control unit 13
Performs transmission of image data to the image recording unit 9 and various processes, and also performs various calculations and the like on the image data in the dampening solution supply operation according to the present invention. That is, the control unit 13 also functions as an arithmetic unit or the like for calculating a necessary dampening water amount from the image data.

Next, the operation of the printing apparatus according to the present embodiment will be described with reference to the flowchart of FIG. In addition,
FIG. 3A shows a flow of the entire printing operation, and FIG.
Shows the flow of the dampening solution supply operation. In the figure, first, when a printing operation is started, various initial settings are made on the printing apparatus in step S1. For example, selection of image data to be used for a printing operation, preset of each mechanism, and the like are performed.

In step S2, the two printing plates P taken out of the plate supply / discharge unit 8 are sequentially mounted on the plate cylinder 1 at opposing positions. In the following step S3, images are recorded on the two printing plates P by the image recording unit 9. Then, in step S4, the developing unit 10 approaches the plate cylinder 1, and the developing process is performed on the two recorded printing plates P. After the development processing, the developing unit 10 is retracted from the plate cylinder 1.

In step S5, a printing operation is performed.
In this printing operation, dampening water is first supplied from the dampening water supply unit 11 to the two printing plates on the plate cylinder 1. Details of the dampening solution supply procedure will be described later. Next, ink is selectively supplied to the corresponding printing plates by the two ink supply means 12. The two color ink images on the printing plate P are transferred to the blanket cylinder 2. On the other hand, printing paper is supplied to the impression cylinder 3 from the paper supply unit 8 and the paper supply cylinder 4, and the printing cylinder 3 makes two rotations while contacting the blanket cylinder 2. Thus, two color ink images are sequentially overprinted on the printing paper on the impression cylinder 3. Then, from the impression cylinder 3 to the discharge cylinder 5
Then, the printing paper on which the two-color printing has been performed is discharged via the paper discharging unit 7. In this printing operation, the above steps are repeated,
Printing of a desired number is performed.

When the printing operation is completed, the used printing plate is peeled off from the plate cylinder 1 in step S6, and is stored again in the plate supply / discharge unit 8. Then, in step S7, processes such as blanket cleaning and ink cleaning are performed, and the entire operation is completed. Of course, another printing operation may be continued without finishing the operation.

In the above-described embodiment, an example in which two-color printing is performed on printing paper has been described. However, the present invention can be applied to, for example, general four-color printing. More specifically, a second printing unit having the same configuration as the plate cylinder 1, the blanket cylinder 2, the impression cylinder 3, the paper feed cylinder 4, the discharge cylinder 5, and the like is provided. If the paper is supplied to the next printing unit by a transfer cylinder (not shown) or the like and then the next two-color printing is performed, multicolor printing of a total of four colors can be performed. The same applies to printing of six or more colors. Further, if a reversing device for reversing the front and back of the printing paper is provided between each printing unit, double-sided printing can be performed.

Next, a procedure for supplying dampening water in the present embodiment will be described with reference to FIG. First, in step S11, image data to be used for dampening solution supply is calculated using the original image data for the image on the printing plate. Hereafter, the image data for use in the dampening solution supply is referred to as dampening solution supply image data, and the dampening solution supply image data indicates the required dampening water amount for convenience. Shall be expressed as

In this calculation, since the dampening solution is supplied at a lower resolution than the image on the printing plate, the original image data is converted in resolution to create dampening solution supply image data. At this time, the image data for dampening water supply is inverted and converted with respect to the original image data. That is, the original image data represents the image density of the ink, and the image density of the dampening solution is preferably supplied so as to substantially contradict the image density of the ink. The dampening water supply image data may be created by an image data creation device upstream of the printing device.

In the next step S12, the image density value of the dampening solution in the dampening solution supply image data is converted into an area gradation by an error diffusion method, a dither method or the like. For conversion into the area gradation, the correlation between the dampening water image density and the actual dampening water amount is experimentally obtained in advance to determine the conversion rate. Thus, the image density of the dampening solution is expressed by the number of pixels of the dampening solution. In step S13, discharge of dampening water is controlled at an appropriate timing according to the rotation of the plate cylinder based on the obtained area gradation. As a result, a large number of dampening solution pixels are discharged to a portion having a high dampening solution concentration, and a small number of dampening solution pixels are discharged to a portion having a low dampening solution concentration, so that necessary dampening solution can be supplied. If the resolution is low and the dampening solution discharged from the inkjet head 20 becomes uneven, the printing plate surface after the dampening solution has been discharged may be leveled by the leveling roller 21 or the like.

On the other hand, the above-mentioned dampening solution image data uses multi-gradation image data obtained by performing gradation conversion on the original image data. R
Binary image data that has been subjected to IP processing may be used. In this case, for example, the required image density of the dampening solution may be calculated by counting the number of pixels for each predetermined area. Alternatively, the dampening solution may be discharged by inverting the bitmap image data. Furthermore, PIP of CIP3 standard used for setting the ink supply amount of the printing apparatus
If data is used, the required amount of ink can be calculated for each predetermined area, so that the dampening solution supply amount may be calculated relative to this amount of ink.

According to the above embodiment, since the dampening solution is supplied using the dampening solution discharging means such as the ink jet head, it is possible to supply an accurate amount of dampening solution corresponding to the image on the printing plate. . Thereby, print quality can be improved. In particular, a printing apparatus including an image recording apparatus that records an image on a printing plate, such as the printing apparatus according to the present embodiment, is suitable because the amount of dampening water can be adjusted using image data. Further, in a printing apparatus of the type in which two plates are held on a plate cylinder as in the printing apparatus according to the embodiment of the present application, since dampening water can be supplied in a non-contact manner, different colors of ink are used for the stored dampening water. There is also an advantage that a single dampening water supply device can be used without mixing.

[Second Embodiment] Next, FIGS.
The second embodiment will be described with reference to FIG. FIG. 4
6 are diagrams corresponding to FIGS. 1 to 3, respectively. FIG. 4 is a schematic side view of the printing apparatus, FIG. 5 is a diagram showing the relationship between the dampening solution supply unit and the slope cylinder, and FIG. It is a flowchart of a water supply procedure. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description is omitted.

In FIG. 4, in the second embodiment, a dampening solution supply unit 30 includes a first dampening solution supply unit 31 that uniformly supplies dampening solution to the corresponding printing plates. The second embodiment differs from the first embodiment in that the second embodiment includes a second dampening solution supply unit 32 that supplies an additional dampening solution. In the second embodiment, the first dampening solution supply unit 31 uniformly supplies a substantially minimum necessary amount of dampening solution to the printing plate surface, and requires a large amount of dampening solution on the printing plate. The additional dampening water is supplied by the second dampening water supply means 32 at the portion indicated by. Hereinafter, this will be described in detail.

The first dampening water supply means 31 has a general configuration in which dampening water stored in a watercraft is pumped up by a water source roller and applied to a corresponding printing plate surface by a dampening roller. I have. The first dampening solution supply means 31
Two sets are arranged to correspond to one printing plate,
Each drip roller is configured to move up and down with respect to the plate cylinder by a cam mechanism (not shown) so as to selectively contact the corresponding printing plate. In the first dampening solution supply means 31, a uniform prescribed amount of dampening solution can be applied to each printing plate.

The second dampening water supply means 32 comprises an ink jet head 33 as shown in FIG.
This inkjet head 33 differs from the first embodiment in that the width size is configured to cover the image area R on the printing plate P. On the other hand, as shown in FIG. 2, the first dampening solution supply means is arranged so as to cover substantially the entire width of the printing plate, similarly to the ink jet head 20 in the first embodiment. This is to wet the margins at the left and right ends of the printing plate.
In FIG. 2, for convenience, the first dampening solution supply means 31 and the second dampening solution supply means 32 are shown side by side in the vertical direction in the figure.

In the second embodiment, the dampening solution storage tanks 22 and 22 'used in the first dampening solution supply means and the second dampening solution supply means are separately separated. This is because the dampening water used in the second dampening water supply means 32 is subjected to various treatments suitable for discharge, preservative treatment, filtration treatment, and the like. This is because ink is mixed by the contact of the wetting roller, which may cause clogging of the ink jet head.

Next, a procedure for supplying dampening water in the second embodiment will be described with reference to FIG. First, step S
At 21, the dampening water supply image data is calculated as in step S11. As described above, the dampening solution supply image data indicates the image density of the dampening solution on the printing plate surface.

In the next step S22, the dampening water corresponding to the specified amount of dampening water supplied by the first dampening water supply means 31 is obtained from each dampening water image density in the dampening water supply image data. Subtract the image density. Here, if the dampening solution image density after the difference calculation is 0 or less, the corresponding dampening solution image density is set to 0, and no additional dampening solution by the second dampening solution supply means 32 is required. That is, the amount of dampening water supplied to the corresponding area by the first dampening water supply means 31 is sufficient. On the other hand, if the dampening solution image density after the difference calculation is 0 or more, it is necessary to add dampening solution by the second dampening solution supply means 32 in accordance with the obtained difference.

In step S23, based on the difference amount of the dampening solution image density, the image is converted into an area gradation as in step S12. Then, in step S24, dampening water is supplied from the second dampening water supply means 32 based on the obtained area gradation.

As described above, in the second embodiment, since the first dampening solution supply means 31 is used in combination, the number of ejections of the ink jet head 33 can be reduced as compared with the first embodiment. it can. Therefore, for example, it is possible to extend the life of the head, which is said to be limited to the discharge of several billion dots per nozzle in a general color printer or the like. Further, the length of the ink jet head 33 only needs to correspond to the image area R, so that the length can be shortened as compared with the first embodiment.

In the second embodiment, as in the first embodiment, the second dampening solution supply means dampens the dampening water based on the bitmap image data itself when the printing plate is recorded. Water may be discharged.

[Other Embodiments] In the second embodiment, any dampening water supply means may be selectively used as appropriate according to the work content. For example, in the case of work that does not matter much in print quality or adjustment work such as test printing, the dampening solution is adjusted only by the first dampening solution supply means by a conventional method, and a more precise print quality is required. In this case, the dampening water may be supplied by the second dampening water supply means or by both dampening water supply means. Thereby, the consumption of the inkjet head 33 can be suppressed. Such switching can be achieved by the operator appropriately switching the operation mode. Further, the dampening solution supply means of the present embodiment can adjust in real time based on various printing conditions and printing environments, for example, types of printing paper and ink to be used, temperature and humidity around the printing apparatus, and the like.

[0055]

According to the present invention, the amount of dampening water can be varied along the axial direction of the plate cylinder and the rotational direction of the plate cylinder.
Appropriate dampening water can be supplied according to the distribution of images on the printing plate. Thus, it is possible to prevent the amount of dampening water in each part of the printing plate from being excessive or insufficient, and to obtain optimal printing quality.

[Brief description of the drawings]

FIG. 1 is a schematic side view showing an example of a printing apparatus including a dampening solution supply device according to an embodiment of the present invention.

FIG. 2 is a plan view showing a configuration of a dampening solution supply device of the printing apparatus.

FIG. 3 is a flowchart illustrating a work procedure and a dampening solution supply procedure in the printing apparatus.

FIG. 4 is a schematic side view illustrating an example of a printing apparatus including a dampening solution supply device according to a second embodiment.

FIG. 5 is a plan view showing a configuration of a dampening solution supply device according to a second embodiment.

FIG. 6 is a flowchart showing a dampening solution supply procedure according to the second embodiment.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 plate cylinder 2 blanket cylinder 3 impression cylinder 9 image recording section 10 developing section 11 dampening solution supply section 12 ink supply means 13 control section 20 inkjet head 21 leveling roller 22, 22 'dampening solution storage tank 31 first wetness Fountain solution supply means 32 second fountain solution supply means 33 inkjet head

Claims (12)

[Claims] 1. A fountain solution supply device for supplying fountain solution to a printing plate provided on a peripheral surface of a plate cylinder, wherein the fountain solution supply device is arranged along a plate cylinder axis direction and is independent of the printing plate surface. A plurality of dampening solution discharge means capable of discharging a dampening solution, and controlling a dampening solution discharge amount discharged from each dampening water discharge means in a time series along the rotation direction of the plate cylinder. And a control means. 2. The fountain solution supply device according to claim 1, wherein the fountain solution discharging means is an ink jet head type capable of discharging fountain solution in a unit of one drop to a printing plate surface. 3. A dampening solution supply image data for supplying dampening solution is calculated based on image data corresponding to an image on the printing plate, and dampening solution supply image data is calculated using the dampening solution supply image data. The dampening water supply device according to claim 1 or 2, wherein the dampening water amount is controlled. 4. A fountain solution according to claim 1, further comprising a leveling roller for leveling the fountain solution discharged by the fountain solution discharging means on a printing plate surface. Feeding device. 5. A fountain solution supply device for supplying a fountain solution to a printing plate surface provided on a peripheral surface of a plate cylinder, wherein a predetermined amount of fountain solution is supplied substantially uniformly to the printing plate surface. A first dampening solution supply unit, and a second dampening solution supply unit that selectively supplies additional dampening solution to a desired position on the printing plate surface. A dampening water supply device capable of supplying a dampening water amount corresponding to an image on a printing plate surface by a sum of a dampening water amount by the second dampening water supply unit and a dampening water amount by the second dampening water supply unit. 6. A plurality of dampening solutions arranged along the plate cylinder axis direction and capable of independently discharging dampening solution to the printing plate surface. The discharging means, and control means for controlling a dampening solution discharge amount discharged from the dampening water discharging means in a plate cylinder axial direction and a rotation direction of the plate cylinder. The fountain solution supply device as described in the above. 7. A dampening solution supply image data for supplying dampening solution based on image data corresponding to an image on the printing plate, and a dampening solution of the dampening solution supply image data is calculated. Additional dampening water is supplied from the second dampening water supply means for an image density exceeding the dampening water image density corresponding to the prescribed amount of the first dampening water supply means. The dampening solution supply device according to claim 6, characterized in that: 8. A printing apparatus for supplying a fountain solution and ink to a printing plate mounted on a plate cylinder and transferring an ink image on the printing plate surface to printing paper for printing, wherein the axial direction of the plate cylinder is provided. Provide a dampening solution discharge head in which a plurality of discharge elements are arranged along, vary the dampening solution discharge amount discharged from each discharge element with the rotation of the plate cylinder, to a desired portion on the printing plate surface 2
A printing device that can dimensionally supply fountain solution volume. 9. A dampening solution supply image data is created from image data corresponding to an image on a printing plate, and dampening solution is supplied from the plurality of ejection elements based on the obtained dampening solution supply image data. 9. A printing apparatus according to claim 8, further comprising control means for controlling so as to selectively discharge the printing medium. 10. The printing apparatus according to claim 9, further comprising image recording means for recording an image on a printing plate held on a plate cylinder based on the image data. 11. The printing apparatus according to claim 10, wherein a resolution of the dampening solution discharge head is lower than a resolution of the printing plate recording unit. 12. The printing apparatus according to claim 8, further comprising another dampening solution supply means for supplying dampening solution substantially uniformly to the printing plate surface.