JP2918487B2 - Method and apparatus for performing gravure printing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION The present invention uses a gravure printing plate formed from a gravure printing base plate having a basic mesh having a receiving capacity greater than the maximum amount of ink to be transferred and which can be erased and reused. Method and apparatus for gravure printing.

[0002]

2. Description of the Related Art Gravure printing is a printing method in which printing is performed using cells that are lower than the plate surface. In this method, ink is completely applied to a printing plate. After that, the printing ink is wiped off the surface. Then, the printing ink is left only in the cells. As the printing plate, a copper-plated steel cylinder, a cylinder having a cavity and fitted with a rod, or the like is used, and a copper plate wound around the cylinder is often used.

In this printing method, after the ink is applied, the doctor blade wipes off the ink from the printing plate surface, so that pure surface printing cannot be performed. Also, the entire image needs to be decomposed into lines, dots, or halftone dots. Due to the different depths and areas of the individual cells, the cells receive different amounts of printing ink, so that the printed image has different ink strengths at individual points of the image.

Various methods are used today for producing gravure printing plates. For example, the method of changing the depth uses the principle of corrosion in which a concentrated iron (ferric) chloride solution is slowly penetrated into the pigment gelatin layer. The pigment transferred onto the copper printing plate is formed from a hardened gelatin layer, which corresponds to the tone of the positive film. The engraving method is characterized in that an image portion and text are scanned line by line with an optical element, and at the same time, a printing plate is engraved with an engraving head. A particular emphasis in this method is that the cells are formed in the copper layer of the printing plate by high energy electron beams. The electron beam is directed toward the base plate in a vacuum and irradiated, and the plate material is removed according to the image portion. In the printing plate engraved in this way,
It is possible to provide a mesh that can change depth and area during engraving.

Similarly, it is possible to form a cell using a high-power laser beam. In this case, it should be noted that appropriate measures must be taken to ensure that the laser beam energy is absorbed by the master. In particular, copper must be treated without special precautions.
This is because the laser beam is largely reflected.

[0006] Furthermore, DE-27-48-062 describes a method for producing an engraved printing plate. In this method, first, a gravure printing base plate is prepared in which concave portions having the same depth and area are uniformly provided on the surface.
Next, the engraved surface is covered with a photosensitive material so that all the concave portions are filled. Thereafter, the printing substrate is exposed photographically according to a predetermined image area, and the exposed area is polymerized. Then, the unexposed portion is washed away, whereby an image portion is formed on the printing base plate. This applies to all gravure printing methods, but that the image area of the printing plate is lower than the non-image area,
It is generally accepted. In particular, in the case of gravure printing using a doctor blade, a mesh is formed from vertical pieces having a uniform height, and the vertical section defines an image area and a surface for guiding the doctor blade. Is defined. At this time, a plate cylinder having a unique plate for each printing process (one plate cylinder corresponding to a predetermined print page for each printing ink) is required. These cylinders are formed to have a required cylinder circumference depending on the dimensions of the print. When operating a gravure or rotary printing press, the appropriate plate cylinder is replaced each time. For such a torso,
For example, a 200 cm width weighs approximately 800 kg today. However, since the above-described method can only be carried out outside the printing press, changing plates requires a great deal of mechanical expense. In addition, all of these manufacturing methods are electroplating,
Since it has manufacturing processes such as coating, exposure and development,
It is not possible to reuse the same printing plate without extensive, especially chemical, treatment. Further, in many cases, in order to extend the service life, chromium plating is performed after corrosion or engraving corresponding to the image area, that is, after removing the plate material.

When printing plates are stored when printing is repeated, it is basically necessary to prepare a place for storing all cylinders. Furthermore, the production of printing plates is very laborious and expensive, especially when electroplating procedures are required. Furthermore, the generation of toxic sludge is problematic from an environmental point of view.

On the other hand, German Published Patent Application DE-38-37-9
According to the method of manufacturing a gravure printing plate disclosed in No. 41-C2, not only can the image portion be formed directly inside the printing machine, but also the image portion of the printing plate can be erased within the printing machine and a new image can be formed. It is possible to make preparations for forming an image area. Furthermore, this method produces a printing substrate with a mesh having a receiving capacity greater than the maximum amount of ink to be transferred. In the printing machine, using the nozzle of the pixel transfer mechanism,
Alternatively, by thermal transfer correlated with the image area, an amount of the thermoplastic plastic material is injected into the concave portion in an inverse proportion to the pixel intensity information, and the receiving volume of the concave portion is reduced. That is, in order to form an image portion of a gravure printing plate,
The filling material is applied in accordance with the image area in a manner reverse to the other methods. Then, in the printing machine, after printing, the thermoplastic material is liquefied by a heat source and removed again from the plate cylinder by a cleaner and / or an (air) blasting device or a suction device.

However, the method of applying the filling material in accordance with the image portion has a problem with respect to the positioning accuracy in forming the image portion. It is not impossible to completely inject the filling material lying on the flank into the recess. However, the filling material needs to be completely injected into the recess so that the entire injected filling material properly contributes to the reduction of the receiving volume of the recess in the desired manner.

The main object of the present invention is to provide a method and an apparatus for gravure printing in which a gravure printing plate can be directly manufactured at low cost in a printing machine, and the positioning accuracy for forming an image area is improved. And

[0011]

The above object is attained by claim 1.
And a device for performing the method according to claim 25.

By means of the above measures, a cycle having typical steps is repeated, so that it is not necessary to maintain a place for storing a gravure printing plate.

Another particular advantage of the method according to the invention and of the device for carrying out the method is that the wear of the gravure printing plate is compensated. This is because the maximum depth of the image area formed in the filling material applied on the gravure printing plate is clearly smaller than the original depth of the basic mesh of the base plate before application. is there. In other words, the mesh depth becomes smaller due to the wear of the vertical pieces,
Nevertheless, the state where the maximum depth of the image portion is smaller than the mesh depth is maintained for a long time. Therefore, it is preferable to form the vertical piece of the base plate as perpendicular to the surface of the gravure printing plate as possible.

[0014] Advantageous embodiments of the invention are set out in the subclaims.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments and modifications of the present invention will be described below with reference to the drawings. The figures are drawn very diagrammatically. FIG. 1 is a diagram showing a basic configuration of a mechanism for performing a method according to the present invention. FIG. 2 is a detailed view showing the surface of the gravure printing base plate used. FIG. 3 is a diagram illustrating a process of removing (ablating) a filler material that can be liquefied from the surface of the gravure printing plate in proportion to the laser beam intensity in accordance with the image portion for each scanning line. FIG. 4 shows one embodiment of the device according to the invention. FIG. 5 is a diagram showing a filling material application device. FIG. 6 is a diagram showing a pixel transfer mechanism using an absorption function for performing removal according to an image area. FIG. 7 is a diagram showing an arrangement structure of a micromirror for a pixel transfer mechanism for performing removal according to an image portion. Figures 8 and 9
FIG. 8 is a diagram illustrating a mechanism for performing removal according to the image area illustrated in FIG. 7.

The image formation of the printing substrate 1 can be carried out directly in a printing machine by the method and the device according to the invention. The gravure printing plate on which the image is formed is erased in a printing machine in a simple manner and can be prepared for the formation of a new image.

As shown in FIG. 1, a gravure printing base plate 1 having a basic mesh having a receiving capacity not less than the maximum amount of ink to be transferred and before forming a printing plate is firstly filled with a filling material applying device. Is filled using a liquefiable substance (filling step 2). As the filling material, a thermoplastic resin, a wax (melt type), a rack varnish, or a reticulable polymer melt or polymer solution which is also called a reactive system and has very high abrasion resistance is used. Next, the surface of the gravure printing plate is approximately flattened. Thereafter, the filled material is removed (ablated) from the concave portion according to the image portion by the action of the thermal energy of the pixel transfer mechanism (removal step 3). Then, the gravure printing plate is applied with ink by an ink application device (ink application step 4), and printing is performed on the printing material 5 by gravure printing (printing step 6).

After the printing step 6, the residual ink is removed from the surface of the gravure printing plate, and the reproducing step 7 is executed. Preferably, the liquefiable filling material is completely melted out of the recesses of the base plate (regeneration step 8), after which the recesses are evenly filled again. The step of melting the liquefied substance from the concave portion of the base plate can be performed by a heat source and / or an air blast device or a suction device.

FIG. 2 shows a cylinder 10 having a vertical piece 9 before forming a printing plate. The hanging piece 9 is spirally formed at a predetermined angle on the cylindrical surface of the body. The lobes are preferably spaced apart from one another with a distance corresponding to today's net gravure. For a mesh of 80 pieces / cm, the above distance is about 125 microns. However, there was no deflection that was recognized by the doctor blade,
As long as the bending does not cause excessive wear of the hanging pieces 9 and the hanging pieces 9 reliably guide the doctor blade, the distance between the hanging pieces may be larger. The gravure printing base plate 1 usually has abrasion resistance at least on the surface of the flank portion. For example, the printing substrate 1 may be coated with chromium or titanium oxide, it may be originally made of ceramic and very rigid, and / or the doctor blade may be coated on a particular liquid film during printing. There may be a case in which specific irregularities are provided so that the object moves smoothly.

After the concave portion between the vertical pieces 9 of the gravure printing base plate 1 is filled with a liquefied filler material made of thermoplastic plastic, as shown in FIG. In particular, a pixel is formed on the gravure printing plate 20 according to an image portion by a pixel transfer mechanism using a thermal energy effect by the laser beam 21. In this case, it is preferable to use an NdYAG or NdYLF laser, and this laser beam is modulated to a multi-step intensity (23) through an acousto-optic modulator. At this time, the laser beam 22 is guided to the gravure printing base plate 1 through a glass fiber lens, and is focused on the base plate. Note that the cell size does not exceed about 2/10 mm. That is, the removal (ablation) step 3 corresponding to the image area
When executing, the dripping part appears when it exceeds 2/10 mm, but at this time, the dripping part is not for guiding the doctor blade for ink, but discharges all ink from the cell at the time of printing Works like that. Therefore, positioning is performed for a pixel smaller than the original gravure printing cell, and as a result, one cell is formed from a large number of pixels.

Further, by rotating the filled gravure printing base plate 1 at a high speed to vaporize a part of the filler material to be removed and centrifuging it, the removal step 3 corresponding to the image area is supported. It is possible.

As another advantageous method, there is a method in which the gravure printing base plate 1 is not formed as a complete cylinder, but is formed in a layer shape so as to reduce the heat capacity. That is, the thickness of several tens mm on which the basic mesh of the gravure printing base plate 1 is placed.
A heat insulation layer made of, for example, a carbon material reinforced with glass fiber is provided between the surface layer of the base material and the base body.
In this case, a resin, a synthetic wax or a natural wax is used as the thermoplastic plastic used as the liquefiable filling material.

FIG. 4 shows a preferred embodiment of the device for carrying out the method according to the invention.

Inside the gravure printing machine there is operatively mounted a device 11 for directly applying a liquefiable filling material to the gravure printing cylinder 10 on which the gravure printing master 1 is mounted. A preferred embodiment of this device 11 is shown in FIG. The coating device 11 is configured to open toward the surface of the gravure printing base plate 1 and have a container 11a in which a heating cartridge 11b is incorporated. Apparatus 11 includes a heated, molten thermoplastic 11c that can be filled or refilled as granules. The melt 11c is sent to the surface of the gravure printing base plate 1 by gravity and capillary action,
Penetrates into the recesses of the basic mesh. In this case, it is also possible to use air pressure or hydraulic pressure using a pump instead of gravity. Capillary and hydrodynamic forces act on a narrow gap (slit) between the gravure printing base plate 1 and the liquefiable filler filling device 11, and the amount just required for filling is obtained. Is supplied.

In the configuration of the modified example of this embodiment, as shown in FIG. 5, the device 11 is provided with two bent portions 11d and 11e. One forming part 1
1e is disposed in front of a narrow gap between the gravure printing base plate 1 and the filling material applying device 11 as viewed from the rotation direction of the gravure printing plate cylinder 10, and the other shaped portion 11d is disposed behind. ing. Forming part 11 arranged behind the gap
d is a cylinder 1 using a precise guide member or support member.
It is held at a very small distance (less than 1/100 mm) from 0 and is heatable to adjust the viscosity of the filling material. This ensures that the hydrodynamic forces work effectively and that the depressions of the basic mesh are completely filled. Further, the rear end of the run-shaped portion 11d is sharply formed so that the filling material can be cleanly discharged from the gap. In addition, since the shaping portion 11e disposed at the front is held at a larger distance (not less than a few hundredths of mm and not more than a tenths of not more than 1/2 mm) from the plate cylinder 10,
The gap that grows larger is filled with the filling material, but the effect of the hydrodynamic force is weakened. This step and the preliminary filling step performed in the region of the stamping portion 11d are performed by heating and preliminarily filling the surface of the heat-insulating printing base plate.

The liquefiable substance 11c may be excessively applied on the gravure printing base plate 1 in a heated state. In this case, after the filling material is cooled, the surplus portion can be removed from the gravure printing base plate 1 using the detachable doctor blade 12. That is, it is scraped off with a doctor blade and / or polished and removed. The doctor blade 12 is replaceable. After cooling the thermoplastic, the surface of the gravure printing base plate 1 is subjected to finish polishing while being filled,
It is adjusted so as to eliminate surface irregularities.

Then, after the removal step 3 corresponding to the image area of the filled gravure printing base plate 1 is completed, ink is applied by the ink applying device 13. In this step,
Preferably, a chamber doctor is used. this is,
This is because the chamber doctor requires less space around the cylinder than the conventional ink applicator and can be easily separated from the gravure printing cylinder 10 when other processes are performed. During the application of the ink, the filling material applying device 11, the doctor blade 12, the pixel transfer mechanism (for example, the laser beam 21), and other devices are, of course, gravure printing cylinders for protection from ink and ink spray. 10 can be removed.

As shown in FIG. 4, in gravure printing, in particular, indirect (offset) gravure printing, the printing material 5 is printed by being pressed by an impression cylinder 14. In offset gravure printing, printing is not performed directly on paper from the plate cylinder, but a roller covered with a flat rubber surface is interposed between the plate cylinder and the paper. When this roller functions as a transfer roller, it becomes possible to separate the plate cylinder from the printing medium. In conventional direct gravure printing, the two solid materials come into contact in the printing gap between the plate cylinder and the substrate, so that one of the substrates, the substrate, scrapes the printing plate It has an effect, and in order to counter this effect, a hard material is required for the plate cylinder. However, in offset gravure printing, there are two printing gaps, and in each gap, a hard material and a soft material come into contact. Furthermore, the plate cylinder does not come into direct contact with the paper which has a scraping effect. Thereby, a softer material can be used as the plate material without reducing the durability of the plate material. In addition, regarding the part near the doctor blade, which is another part to be worn on the plate cylinder, the doctor blade is guided by a vertical piece formed of a hard material, but is provided with a soft filling material suitable for removal by heat. Is
No contact during the printing process. Therefore, by using this means, the service life of the gravure printing plate formed according to the present invention is remarkably improved.

After printing the required plate, the residual ink is removed from the gravure printing plate by using a regenerating device 15 which is formed as a detachable system like a chamber doctor, especially in the form of an ultrasonic cleaning device. At the same time, the liquefiable filler material is removed from the recesses of the basic mesh of the gravure printing plate 1. This allows
A cycle of (filling step 2, removing step 3 corresponding to the image area, ink applying step 4, printing step 6, regenerating steps 7, 8) can be newly started.

The ultrasonic cleaning device has at least two
It is possible to work at two different levels. At low ultrasonic energy and / or liquid compatible levels, only the ink is melted and the removal of residual ink is performed. Also, at levels corresponding to high ultrasonic energy and / or other cleaning media, partial or total removal of the fill material is performed.

Yet another important advantage of the present invention is that
A clear improvement in image quality over conventional gravure printing, especially the quality improvement of text reproduction. This point becomes possible when the resolution (resolution) for forming the image portion has, for example, 500 lines / cm within the range of the distance between the two perpendicular pieces.
That is, since the text is scanned at such a high resolution, it is possible to realize much sharper character edges than in the case of the conventional gravure printing. In general, the lower limit of resolution for good text reproduction is approximately
It is 400 lines / cm. The formation of conventional gravure printing plates is performed at a resolution of up to 120 lines / cm, so sharp edges with some small dots may appear to be separated by drippings, Gravure-printed characters always have a so-called sawtooth form.

In the image area, in order to realize the same level of gray scale as in gravure printing in which individual pixel depths vary up to 200 steps, it is necessary to use an exposure apparatus capable of changing the area two-dimensionally, that is, at least 1000 times. It is necessary to record in books / cm. The present invention is also suitable in principle for this two-dimensional recording method. However, here, a so-called hybrid mesh formation, which is a mixed form of mesh formation in which the area can be changed and conventional mesh formation in which the depth can be changed, is used. This mesh can be recorded at, for example, 500 lines / cm, and each point has many depth steps. Taking a resolution of 500 lines / cm as an example, five different depths (0%, 25%, 50%, 75%, 100%) are used in this case. The resulting halftone level is two lines (0 or 100) at a resolution of 1000 lines / cm.
%) Or the case where the depth can be changed to 101 steps at a resolution of 100 lines / cm. Also, using 10 different depths, the amount of information in that case is 100 lines / cm
Equivalent to 250 gray scales when recorded with. Although current density (gradation) information typically uses 256 levels of resolution, hybrids often have clearly less than 256 levels per decomposition point, ie, about 10 levels. In order to convert the gradation information into a mesh formation type, a technique of “error dispersion” based on a dither method or a random scan, which is a well-known method, is used in a pre-printing stage. Typically, these methods use a binary scan, but can be extended to scans with more than two steps. In particular, forming the pixels to have different depths allows multi-step scanning between 2 and 256.

In conventional gravure printing, from 20 microns
To reduce the maximum depth of the cells between 40 microns, high pigmented, especially water-based inks have been used.
The advantage of reducing the cell depth in this way is that the image forming power required for increasing the density of the designated ink can be made smaller, and less water penetrates into the paper, and thereby, The drying speed is significantly increased.

The wear of the gravure printing plate is compensated by the fact that the maximum cell depth for forming the image portion is significantly smaller than the depth of the concave portion of the gravure printing base plate before forming the printing plate. Even if the depth of the concave portion is reduced due to the wear of the vertical portion, the state where the cell depth for forming the image portion is smaller than the concave portion depth is maintained for a long period of time. For this purpose, the hanging pieces need to be formed so as to have vertical walls as much as possible. The increase in the thickness of the vertical portion and the narrowing of the concave portion are technically compensated by deriving a volume characteristic curve at each time during the exposure process and performing a corresponding correction.

With respect to the measures according to the invention, various advantageous variants are conceivable. Instead of the gravure printing base plate in which the vertical pieces are spirally attached as described above, a base plate in which the concave portions are regularly arranged is the same as that used in conventional plate making. It is also possible to use. The size of the concave portion varies from a fine mesh of 80 microns as used today to a very large mesh in terms of area, for example, 1 mm or more. In addition, the concave portions of the plate may be randomly arranged instead of regularly arranged in order to prevent moire from being formed, especially in multicolor printing. Random alignment is achieved, for example, by exposing gelatin, which is used for conventional erosion, using fine dots formed by coherent laser beams instead of crossed screens. In this case, it is preferable to use a wax mixed with 5% of carbon black as the filling material.

Regeneration of the gravure printing plate can also be performed using a high-pressure water flow. For this purpose, the mechanism already published in European Patent Publication EP-9-310-798 is used. Such a mechanism is configured with a double-walled chamber that opens into the gravure printing plate and is isolated from the surroundings by a packing guided on the printing plate. A nozzle is installed inside the nozzle, and the nozzle jets water at a high pressure onto the surface of the gravure printing plate. Then, moisture is absorbed from the coated area outside the chamber, and after this procedure, the gravure printing plate is left clean and dry.

The high pressure water stream cleaning device described above operates at at least two different levels. At low water pressure and / or low water temperature levels, mainly residual ink removal is performed. Also, at high water pressure and / or high water temperature levels, the filling material is partially or completely removed.

In the high pressure water flow cleaning device described above, different pressure and temperature parameters are set depending on whether the basic cleaning or the intermediate cleaning is performed. Intermediate cleaning of only adhering dirt and residual ink is carried out at relatively low temperatures below 50 ° C. and small pressures of a few bar. If a base cleaning is performed, a temperature in the range where softening or melting occurs and a pressure of 30 bar is used. In some cases, a cleaning agent such as a surfactant and fine particles for enhancing the reaction are added to the cleaning water.

The filling of the concave portion of the gravure printing base plate can also be executed by a coating roller. The roller functions to adsorb and apply the stored filler material and preferably rotates in the opposite direction to the gravure plate cylinder. After the filling material is applied, scraping is performed using a doctor blade. Preferably, the angle of the doctor blade is negative, in which case the doctor blade performs the cutting like a knife. In particular, it is also possible to heat the doctor blade. further,
It is also possible to heat the gravure printing plate by electromagnetic induction before and during filling and during the scraping with a doctor blade. Regeneration, filling and scraping of the printing plate with a doctor blade can be performed during the same rotation of the plate cylinder.

In the case where a thermoplastic is used, for example, a highly absorbent paper which absorbs the thermoplastic from a concave portion by capillary action together with the thermal effect of an infrared ray source or heated air, or an air blast device or a suction device It is possible to use

Further, without removing the filling material, only the dirt and ink adhering to the gravure printing plate are cleaned, and the plate material portion removed at the time of forming the previous image portion is refilled. It is also possible to do. At this time, complete erasure of the master is executed after the specified number of cycles is completed.

As a filler, a photopolymer can be further used. The photopolymer is cured by a laser beam and developed with water. Alternatively, a rack varnish that continuously and completely fills the concave portion by performing multi-layer coating and intermediate drying, or the above-described reaction system or the like is also used as the filling material.
For example, by adding carbon black to the filling material, the filling material becomes photosensitive to the light beam used.

After the surface of the gravure printing plate has been filled, it is smoothed by scraping with a polished or heated doctor blade. Further, the printing plate can be smoothed by injecting heated air or reducing the intensity of a laser beam for performing removal in accordance with an image area. Printing plate smoothing using a laser beam
Irradiation is performed at a much smaller output than the removal corresponding to the image portion, and only melting occurs, so that it can be carried out in the process of forming the normal image portion.

Instead of a single laser beam, in particular a high-energy laser beam, it is also possible to use several beams in parallel. As the light source, for example, a semiconductor laser, particularly a laser array composed of a plurality of semiconductor lasers, Nd
All laser light sources having a heating effect, such as a YAG laser, a CO ₂ laser, and a CO laser, are applicable. Further, when filling the photopolymer, it is necessary to use an ultraviolet ray or a blue laser beam such as an argon laser. If a high resolution is not required, a method such as electric corrosion or high-pressure water flow can be applied instead of the light source in order to perform the plate material removing step.

It is also possible to use an absorbent material (such as blotting paper) cut in accordance with the image area. This method is shown in detail in FIG. The base is formed from a multi-layer film 30 '. In this film, the absorbent material 30a (such as blotting paper)
It is placed on the non-absorbable material 30b. Unnecessary areas are cut and removed using a CAD cutting plotter, as is commonly practiced in film cutting techniques. Next, the film 30 'is contacted onto the gravure plate cylinder 10 on which the filled substrate is mounted. And
By means of the heating roller 31, the film 30 'is thermally transferred onto the gravure printing plate cylinder. At the site where the absorbent film material is placed, the filler material is absorbed by capillary action, and at the site that comes into contact with the non-absorbable material, the filler material is not absorbed. Thereby, the section 32 of the image portion is realized. In this case, the section appears between the two forms of the full tone and the white paper area.

Further, the removal of the plate material corresponding to the image portion can be carried out by using the micro mirror array 40. The structure of such an array 40 is shown in FIG. A typical example of such an array 40 comprises a plurality of individually electrically tiltable micromirrors 41, typically having an area of 20 microns x 20 microns.
These mirrors are arranged in a 1000 × 2000 matrix.

FIGS. 8 and 9 show a mirror array 4 for a pixel transfer mechanism for removing a plate material according to an image area.
1 shows the structure of 0. The mirror array 40 is evenly illuminated by a high energy arc lamp 42 and passes through a lens 43 onto a printing plate surface 44 at about 1 magnification.
An image is formed so that the side of the array 40 of 00 micromirrors is perpendicular to the rotation direction of the plate cylinder. This side part determines the line of the object part. At this time, the pixel
The mirror is defined as the field that is geometrically imaged. As one mirror surface, half of the adjacent non-imaging peripheral region reaching the adjacent mirror belongs. When the micromirror is located at a position where the aperture of the imaging lens can reflect within the specified solid angle, the micromirror reflects the energy irradiated on the mirror to the plate cylinder and the pixels. When the plate cylinder rotates, an image line consisting of 2000 pixels is simultaneously recorded. The mirror performs energy irradiation on the pixel when more than 50% of its area is imaged on the pixel. At this time, the line on the mirror array 40 corresponding to the fixed pixel line on the plate cylinder moves. That is, as the plate cylinder rotates, more and more lines of the mirror array correspond to one pixel line.
(FIG. 9)

Suitable electronic equipment (mainly multi-element =
Using a shift register, output of image portion data synchronized with the line movement is performed. In this case, the object line data is input for the first line, and in synchronization with the rotation of the plate cylinder, the object line data is shifted downward line by line. Entered on the first line. During such movement, the mirror is always on or off. Therefore, each pixel is 0 to 1
It is possible to hold up to 000 levels of energy.
For example, when irradiating a pixel having an energy amount of 4/10 of the maximum energy amount, 400 mirrors are turned “on” while energy is reflected from the mirror during this movement, 600 mirrors are "off". The reflection of the laser beam from the mirror element 41 is changed corresponding to the shift register in synchronization with the rotation of the gravure printing plate surface 44. This will maintain a corresponding energy exposure on the printing plate surface 44 for pixels having unique photosensitive data values throughout the imaging of the mirror array 40 on the plate surface 44. Further, the on / off arrangement of the mirror can be arbitrarily set, but can also be set methodologically.

In principle, pixels smaller than individual concave portions of the basic mesh of the gravure printing base plate 1 can be arbitrarily positioned in the removing step 3 according to the image portion. In this case, the removal step 3 particularly corresponding to the image portion is mainly executed independently for the basic mesh.
However, it is also possible to adapt the removal according to the image area to the basic mesh, that is, to have a certain geometric relationship with the basic mesh. In an ideal case, the removal according to the image area realizes the intact formation of the concave portion of the basic mesh, which is inevitable in the method.

When the cylinder makes one rotation, the print head shifts by 1000 pixels and a new cycle is started. Alternatively, the print head can be moved continuously so that the head shifts by 1000 pixels during one revolution of the plate cylinder.

The above embodiments are all for implementing the method according to the invention inside a gravure printing machine, but of course the method can also be implemented outside a printing machine. .

[Brief description of the drawings]

FIG. 1 shows the basic configuration of a mechanism for implementing the method according to the invention.

FIG. 2 is a detailed view showing the surface of a gravure printing base plate used.

FIG. 3 is a view showing a step of removing a liquefiable filler material in proportion to a laser beam intensity from a surface of a gravure printing plate in accordance with an image portion for each scanning line.

FIG. 4 shows one embodiment of the device according to the invention.

FIG. 5 is a view showing a filling material application device.

FIG. 6 is a diagram showing a pixel transfer mechanism using an absorption function for performing removal according to an image area.

FIG. 7 is a diagram showing an arrangement structure of a micro mirror for a pixel transfer mechanism for performing removal according to an image portion.

8 is a diagram illustrating a mechanism for performing removal according to the image area illustrated in FIG. 7;

FIG. 9 is a diagram showing a mechanism for performing removal according to the image portion shown in FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Gravure printing base plate 2 Filling material application process 3 Removal process according to an image part 4 Ink application process 6 Printing process 7, 8 Reproduction process 9 Vertical piece 10 Plate cylinder 11 Filling material application device 11d, 11e Deformed portion 12 Doctor blade 13 Ink coating device 15 Reproducing device 20 Gravure printing plate 21 Laser beam (pixel transfer mechanism) 30 ', 30a Film (film material) 40 Micromirror array 41 Micromirror element 44 Gravure printing plate surface

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Andreas Schiller, Germany, D-86415, Melling Leonhardstrasse, 70・ Strasse ・ 43 A (56) References JP-A-2-187335 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B41N 1/06 B41C 1/00

Claims (40)

(57) [Claims] 1. A method for performing gravure printing using a gravure printing plate which is formed from a gravure printing base plate having a basic network having a receiving capacity not less than a maximum amount of ink to be transferred and which can be erased and reused. A method, comprising: forming a concave portion of said basic network of a gravure printing plate (1),
Filling material application device using liquefiable filling material (1
(1) a step of uniformly filling by (1), a step (3) of removing the charged material from the concave portion by the pixel transfer mechanism (21) in accordance with the image portion, and Gravure printing plate (20) scanned by
A step (4) of applying ink with an ink coating device (13), a subsequent printing step (6) by gravure printing, and a step (7, 8) of reproducing the gravure printing base plate (1) after the printing step And a step (2) of filling the recesses evenly again. 2. The method for gravure printing according to claim 1, wherein the filling material that can be liquefied by hydrodynamic forces, in particular by capillary action, is liquefied in a gravure printing substrate (1). )
A method for performing gravure printing, characterized in that the concave portions of the basic mesh are filled. 3. The method for gravure printing according to claim 1, wherein a liquefiable filling material is excessively applied to the gravure printing base plate (1) in a liquefied state. A method for performing gravure printing, characterized in that, after solidification and solidification, an excess portion is removed from the gravure printing substrate (1) by a doctor blade (12). 4. A method for performing gravure printing according to claim 1, wherein the gravure printing base is provided by a doctor blade before the excess part of the liquefiable filling material solidifies. By being removed from 1), the filling material is liquefied,
A method for performing grabbing printing characterized in that it is applied on said gravure printing substrate (1) with the same depth as the basic mesh. 5. The method for performing gravure printing according to claim 4, wherein the complete filling of the basic network of the gravure printing base plate (1) is performed by continuously applying a multilayer and performing intermediate drying. A method for performing gravure printing, which is characterized by being performed. 6. The method for performing gravure printing according to claim 1, wherein the removing step (3) according to the image portion is performed by the action of thermal energy. A method for performing gravure printing that specializes in this. 7. The method for gravure printing according to claim 1, wherein the gravure printing base plate (1) coated with a filling material is rotated at a high speed and removed. A method for performing gravure printing, wherein a part of a to-be-printed material is vaporized and centrifuged to support a removal step (3) corresponding to an image portion. 8. The method for gravure printing according to claim 1, wherein the gravure printing base plate (1) is polished again with a filling material applied. A method for performing gravure printing, comprising: 9. The method for performing gravure printing according to claim 1, wherein the application of the ink to the gravure printing plate (20) is performed using a chamber doctor. For performing gravure printing. 10. A method for performing gravure printing according to claim 1, wherein the gravure printing is characterized in that the printing is performed by indirect (offset) gravure printing. The way to do it. 11. A method for performing gravure printing according to claim 1, wherein the gravure printing plate (20) is coated with an ink.
A method for performing gravure printing characterized by using a high pigment ratio, especially an aqueous ink. 12. A method for performing gravure printing according to any one of claims 1 to 11, wherein: a printing cycle (a filling step (2), a removing step (3) corresponding to an image portion; ), The ink application step (4), the printing step (6), and the regeneration step (7, 8)).
Cleaning (7) of the residual ink on the gravure printing plate (20), which has been carried out earlier, and complete replenishment of the liquefiable filling material from the recesses of the basic mesh in a regeneration step (7, 8) For performing gravure printing. 13. The method for performing gravure printing according to claim 1, wherein the gravure printing base plate (1) has a predetermined number of cycles (7, 8) for the regeneration step (7, 8). Coating process of filling material (2), removal process according to the image area (3), ink coating process (4),
Each time the printing step (6) and the regenerating step (7)) elapse,
Complete removal of the liquefiable filler material from the recesses of the basic network was performed, and in the cycle during which the complete removal was performed, it was removed in a removal step (3) corresponding to the image area. A method for performing gravure printing, characterized in that only the liquefiable filling material is refilled. 14. The gravure printing method according to claim 1, wherein a thermoplastic material is used as the liquefiable filling material. The way to do it. 15. The gravure printing method according to claim 1, wherein a photopolymer is used as the liquefiable filling material. The way to do it. 16. The method for performing gravure printing according to claim 1, wherein a rack varnish is used as the liquefiable filling material. the method of. 17. The method for gravure printing according to claim 1, wherein the liquefiable filler is a reticulable polymer melt or polymer solution (reaction system). A method for performing gravure printing, characterized by using: 18. A method for performing gravure printing according to any one of claims 1 to 17, wherein the removing step (3) according to the image portion is performed in accordance with the image portion. The cut film (30 ') is used,
The film is thermally transferred onto the already filled gravure printing substrate (1), and the absorbent film material (30a) arranged in accordance with the image area forms the basis of the gravure printing substrate (1). A method for gravure printing, characterized in that the filling material is sucked out from the concave portions of the mesh. 19. The method for gravure printing according to claim 1, wherein the irradiating is performed uniformly to perform a removing step (3) corresponding to an image portion. A micromirror array (40) is used, consisting of micromirror elements (41) that can be tilted in pixel units and imaged on a gravure printing plate surface (44), the reflection of light rays from the micromirror elements being: The shift register is changed in synchronization with the rotation of the gravure printing plate surface (44), so that each unique photosensitive data value is formed throughout the imaging of the mirror array (40) on the printing plate surface (44). A method for performing gravure printing, characterized in that the corresponding energy irradiation on the printing plate surface (44) is maintained for the pixels having the gravure. 20. A method for performing gravure printing according to any of the preceding claims, wherein pixels smaller than gravure printing cells are formed on the printing plate surface, whereby gravure printing is performed. A method for performing gravure printing, wherein a cell is composed of a plurality of pixels. 21. The method for performing gravure printing according to claim 20, wherein the removal of the plate material is performed on the pixels at a multistep depth from 2 to 256. Method for printing. 22. The method for performing gravure printing according to claim 20, wherein in the removing step (3) corresponding to the image portion, pixels smaller than the concave portions of the basic mesh of the gravure printing base plate (1). Is positioned, and the positioning is performed independently with respect to the mesh. 23. The method for performing gravure printing according to claim 20, wherein in the removing step (3) according to the image portion, pixels smaller than the concave portions of the basic mesh of the gravure printing base plate (1). Are positioned and arranged such that these pixels have a specific geometrical relation to the underlying mesh. 24. Apparatus for performing gravure printing formed to carry out the method according to claim 1, comprising a basic network having a receiving capacity equal to or greater than the maximum amount of ink to be transferred. An applying device (11) for applying a liquefiable filling material to the rotating gravure printing base plate (1) in the rotating direction, and an image portion on the surface of the gravure printing plate (20). Pixel transfer mechanism (2) for performing the removal process (3)
1, 30, 40), an ink application device (13), and a reproduction device (15) for a basic mesh of the gravure printing base plate (1). Equipment for gravure printing. 25. The apparatus for performing gravure printing according to claim 24, wherein the gravure printing base plate (1) is formed in a sleeve shape. 26. The apparatus for performing gravure printing according to claim 24 , wherein the coating apparatus (1) for applying a liquefiable filler material.
1) includes a gravure printing base plate (1) and a coating device (11)
In the direction of rotation of the plate cylinder (10)
A front part and a rear part are provided with a profiled part (11d, 11e), respectively. A sharp rear end is formed in the parted part 11d arranged behind the gap. 10) is held with a very narrow gap (1/100 mm or less) with respect to the plate cylinder (1).
A device for performing gravure printing, characterized in that it is held at a greater distance (2/100 mm to 1/10 mm) from (0). 27. The gravure printing substrate used in the method according to claim 1, wherein said basic mesh is spirally formed at an angle on a cylindrical surface of said printing substrate. A gravure printing base plate comprising a part (9). 28. The gravure printing substrate used in the method according to claim 1, wherein the printing substrate is formed in layers and at least between a surface layer provided with a basic mesh and a support cylinder. And a gravure printing base plate having a heat insulating layer inserted therein. 29. The gravure printing base plate according to claim 28 , wherein the heat insulating layer is formed of a glass fiber reinforced carbon material. 30. The gravure printing base plate according to claim 27, wherein the hanging portion (9) is formed substantially perpendicular to the surface of the gravure printing plate. Gravure printing base plate. 31. A gravure printing substrate used in the method according to claim 1, characterized in that a basic mesh in the form of a regular cell (weight) is formed. 32. The gravure printing substrate used in the method according to claim 1, characterized in that a basic mesh is formed from randomly formed concave portions. 33. The apparatus for performing gravure printing according to claim 24, wherein an ultrasonic cleaning device is used as the reproducing apparatus (15). 34. The apparatus for performing gravure printing according to claim 33 , wherein the ultrasonic cleaning device is operable at at least two different levels, and at low ultrasonic energy and / or liquid compatible levels. Only the ink is melted to remove the residual ink, and at high ultrasonic energy levels, the removal of the filling material from the concave portions of the partial or complete basic mesh is performed. For performing gravure printing. 35. The apparatus for performing gravure printing according to claim 24 , wherein a high-pressure water-flow cleaning apparatus is used as the regenerating apparatus (15). 36. The apparatus for performing gravure printing according to claim 35 , wherein the high-pressure water flow cleaning device is operable at at least two different levels, and at low water pressure and / or low water temperature levels residual ink. And at high water pressure and / or high water temperature levels,
Apparatus for performing gravure printing, characterized in that the removal of charge material from the recesses of a partial or complete basic mesh is performed. 37. The apparatus for performing gravure printing according to claim 24 , wherein a laser beam (21), particularly a high-power laser beam, for applying thermal energy is used as the pixel transfer mechanism. For performing gravure printing. 38. The apparatus for performing gravure printing according to claim 37 , further comprising a semiconductor laser device including a plurality of semiconductor lasers. 39. The apparatus for performing gravure printing according to claim 24 , wherein the pixel transfer mechanism is capable of being thermally transferred onto a basic mesh filled with a gravure printing base plate (1) and has an image area. An apparatus for performing gravure printing, wherein an absorptive film (30) cut according to (1) is used. 40. The apparatus for performing gravure printing according to claim 24 , wherein the pixel transfer mechanism includes a micro mirror array (4).
An apparatus for performing gravure printing, wherein the apparatus according to (1) is used.