EP0730953A2 - Process and apparatus for intaglio printing - Google Patents

Abstract

A device (11) is provided for application of a fluidisable substance. There is a picture point transmission device for ablation (3) on the surface of the photogravure form. An inking system (13) and a regeneration device (15) for the basic grid of the photogravure raw form (1) are incorporated. For the device for application of a fluidisable substance, viewed in the rotation direction of the printing form cylinder (10), a form strip is provided before and after the gap between the printing form (1) and the device. The form strip after the gap has a sharp, rear edge and is held against the cylinder at a very narrow distance (at least 1/100 mm).

Description

The invention relates to a method and a device for gravure printing by means of an erasable and reusable gravure printing form, starting from a gravure printing form with a basic grid designed at least for the maximum amount of ink to be transferred.

Gravure is a printing process with printing elements that are set lower than the surface of the mold. After the printing form has been completely inked, the surface is freed from the printing ink. This only remains in the deepened positions. As a printing form z. B. copper-plated steel cylinders, hollow cylinders pushed onto clamping cores or in some cases copper sheets clamped onto cylinders.

The type of coloring and the squeegee of the mold surface do not allow a pure surface pressure. The entire drawing must be broken down into lines, dots or grid elements. Because of the different depth and size of the individual printing elements, they contain more or less printing ink, which means that the imprint has different color strength at the different image points.

Various working methods for the production of a gravure form are used today. The etching principle of the variable-depth processes is the slow diffusion of concentrated iron chloride solutions through a pigment gelatin layer. The pigment copy on the copper printing form consists of a hardened gelatin relief that corresponds to the tone gradations of the slides. The engraving processes are characterized by scanning image and text line by line with photocells and simultaneously engraving the printing form with engraving heads. Particularly noteworthy is the introduction of depressions into the copper layer of the printing form by means of a high-energy electron beam, which is directed in a vacuum onto the raw form and removes material there. The printing form engraved in this way can be provided with depth and area-variable grids.

Recesses can also be made using a high-energy laser beam, whereby it must be noted that suitable measures must be taken to ensure the coupling of the laser energy into the substrate, since copper in particular largely reflects a laser beam without special pretreatment.

Furthermore, from DE-OS 27 48 062 a method for producing an engraved printing form is known, in which a gravure printing form is first provided by uniformly providing the smooth surface with depressions of the same depth and size, then the engraved surface with a light-sensitive mass is covered so that all the wells are filled. Thereupon the raw form with the desired image is photographically exposed so that the exposed areas polymerize, the unexposed portions can be washed out and this results in an image differentiation.

In general, it can be said that the following applies to all gravure printing processes: image areas of the printing form are lower than non-image areas. In the case of squeegee printing in particular, the raster network forms uniformly high webs which delimit image areas and form a contact surface for the squeegee. A special set of printing form cylinders is required for each print job (one printing form cylinder with a corresponding number of print pages per printing ink). Depending on the print format, these cylinders are manufactured in the required cylinder size. When setting up the rotogravure or rotary printing machine, the corresponding printing form cylinders must be replaced. Such a cylinder z. B. in a width of 200 cm today weighs about 800 kg. Since the previously described methods can only be carried out outside the printing press, this requires a high level of mechanical effort. In addition, each of these production processes includes steps such as electroplating or coating, exposing and developing, which rule out that the same printing form can be reused without extensive, in particular chemical treatment. In addition, chrome plating is usually carried out after the pictorial etching or engraving, i.e. removal of material, to increase the service life.

If the printing form is to be stored for the repeat orders, the space for the entire cylinder must generally be provided. The printing form production is also especially if galvanic steps are necessary, very complex and therefore expensive. The resulting toxic sludge is also ecologically unsafe.

In contrast, DE 38 37 941 C 2 discloses a method for producing an intaglio printing plate, by means of which the imaging can take place directly in the printing press, in addition the imaging of the intaglio printing plate can be deleted in the printing press and prepared again for new imaging. A gravure blank form is also produced with a basic grid designed at least for the maximum amount of ink to be transferred. In the printing press, a quantity of a thermoplastic substance, which is inversely proportional to the image information, is then introduced into the depression from a nozzle of the pixel transmission unit or by image-correlated ironing in order to reduce the scooping volume of the depressions. That is to say, in contrast to the other methods, material is applied imagewise for imaging a gravure blank. After the print job, the thermoplastic substance can then be liquefied in the printing press by means of a heat source and removed again from the printing form cylinder by means of a wiping and / or blowing or suction device.

The pictorial material application, however, poses problems for the positional accuracy of the imaging. It is not readily possible to completely bring material that is placed on the webs into the depressions. However, full insertion is necessary so that the entire transferred material also contributes in a desired manner to reducing the volume of the depressions.

The invention is therefore based on the object of developing a method and a device for gravure printing, as a result of which the gravure printing plate is inexpensive and can also be produced directly in the printing press and the positional accuracy of the imaging is improved.

This object is achieved by the method steps of claim 1 and the device for carrying out the method according to claim 22.

Because the cycle of the characteristic process steps can be repeated, there is no need to store gravure forms.

Another particular advantage of the method according to the invention and the device for carrying out the method is that the gravure blank form wear is compensated for because the maximum imaging depth in the substance applied to the gravure form is significantly less than the original depth of the depressions of the pre-structured raw form. If the depth of the depressions becomes smaller due to wear on the webs, the maximum depth of imaging can still be achieved for a long time. Advantageously, therefore, the webs of the raw form are made as perpendicular as possible to the surface of the gravure form.

An advantageous embodiment can be found in the subclaims.

Fig. 1

den prinzipiellen Aufbau zur Durchführung der erfindungsgemäßen Verfahrensschritte,

Fig. 2

eine Detailansicht der Oberfläche einer verwendeten Tiefdruckrohform,

Fig. 3

eine bildmäßige Ablation der verflüssigbaren Substanz von der Oberfläche einer Tiefdruckform in Abhängigkeit einer vorgegebenen Laserstrahlintensität pro Schreibzeile,

Fig. 4

ein Ausführungsbeispiel einer erfindungsgemäßen Vorrichtung,

Fig. 5

eine Antragsvorrichtung,

Fig. 6

eine Bildpunkt-Übertragungseinrichtung zur bildmäßigen Ablation durch Ansaugen,

Fig. 7

den Aufbau eines Mikrospiegelarrays für eine Bildpunkt-Übertragungseinrichtung zur bildmäßigen Ablation,

Fig. 8 und 9

eine Anordnung zur bildmäßigen Ablation gemäß Fig. 7.

Preferred exemplary embodiments or variants of the invention are explained below with reference to the drawing. It shows a highly schematic:

Fig. 1

the basic structure for carrying out the method steps according to the invention,

Fig. 2

a detailed view of the surface of a gravure blank used,

Fig. 3

an imagewise ablation of the liquefiable substance from the surface of a gravure printing plate as a function of a predetermined laser beam intensity per writing line,

Fig. 4

an embodiment of a device according to the invention,

Fig. 5

an application device,

Fig. 6

a pixel transmission device for imagewise ablation by suction,

Fig. 7

the construction of a micromirror array for a pixel transmission device for imaging ablation,

8 and 9

an arrangement for imagewise ablation according to FIG. 7.

The raw form 1 can therefore be imaged directly in the printing press using the method and the device according to the invention. The illustrated gravure form can also be easily deleted in the printing press and prepared for new imaging.

As shown in FIG. 1, a pre-structured gravure blank 1 with a basic grid designed for at least the maximum amount of ink to be transferred is filled in a first step by means of a liquefiable substance through an application device 2. For example, a thermoplastic or a wax () Hotmelt), lacquers or a crosslinkable polymer melt or solution, which is also referred to as a reactive system and which is characterized by an extremely high abrasion resistance. The surface of the gravure form is then essentially smooth. The filled substance is then removed imagewise from the depressions by the action of thermal energy from a pixel transfer device 3. Now the gravure printing plate can be colored 4 by means of a coloring system, so that it is possible to print on a printing material 5 in gravure 6.

After the printing process 6, the surface of the intaglio printing plate is regenerated again, by removing 7 of ink residues, preferably completely dissolving the liquefiable substance from the pre-structured depressions 8, and filling the depressions uniformly again. The liquefied substance can be extracted from the pre-structured depressions by means of a heat source and / or a blowing or suction device.

Fig. 2 shows a pre-structured rotogravure blank 1 on a cylinder 10 with webs 9 which wind helically at a defined angle around their cylindrical surface. The webs 9 are preferably at a distance from one another which corresponds to the distance of today's gravure screen. For an 80s grid this would be 125 µm. The distance can, however, also be significantly greater as long as the webs 9 still guide the doctor blade reliably without the doctor blade showing a recognizable deflection and without this leading to excessive wear of the webs 9. The gravure blank 1 is usually wear-resistant at least on the web surfaces, for. B. tempered with chrome or titanium oxide or is inherently very hard because of ceramic, and / or is provided with a defined roughness so that the squeegee slides in print on a defined liquid film.

After the depressions between the webs 9 of the intaglio printing blank 1 have been filled with the liquefied substance in the form of a thermoplastic, the intaglio printing forme 20 can then be used according to FIG be burned free in terms of image. NdYAG or NDYLF lasers are preferably used, which are switched in several intensity levels 23 via an acousto-optical modulator. The laser beam 22 can be guided to the gravure blank 1 and focused on it via a glass fiber optic. Care is taken that a well size of more than about 2/10 mm is preferably not exceeded. That is to say, the image-wise ablation 3 produces, at the latest after approximately this distance, a web which is not used to guide an ink squeegee, but rather to force the cell to be emptied of the ink during printing. In particular, areas (pixels) that are smaller than an actual gravure cell can be addressed, so that a cell is generated from a plurality of pixels.

Furthermore, the image-based ablation 3 can be supported in that the filled rotogravure blank 1 is set in rapid rotation in such a way that a part of the material to be removed evaporates and a part is thrown off.

As an advantageous variant, the gravure blank 1 is not designed as a solid cylinder, but is built up in layers in order to achieve a low heat capacity. So between the surface layer of a few tenths of a millimeter thickness, which carries the basic pattern of the gravure blank 1, and a base cylinder, a heat insulating layer, for. B. provided from glass fiber reinforced carbon. The thermoplastic used for the liquefiable substance can also be a resin, a synthetic or natural wax.

Fig. 4 shows a preferred embodiment of an apparatus for performing the method according to the invention.

A device 11 for applying a liquefiable substance is arranged directly on a rotogravure plate cylinder 10, which carries the rotogravure blank form 1, within an intaglio printing machine. A preferred embodiment of this device 11 is illustrated in FIG. 5. This includes one to the surface of the Gravure blank 1 open box 11 a with inserted heating cartridges 11 b. The device 11 is heated and contains the melted thermoplastic 11 c, which can be filled or refilled as granules. The melt 11 c is conveyed by gravity and capillary action to the surface of the gravure blank 1 and penetrates into the depressions of the basic grid. Gravity can also be replaced by air pressure or hydraulic pressure using a pump. A capillary and hydrodynamic force acts through the narrow gap between the gravure blank 1 and the application device 11, which promotes exactly the amount of substance that is required for filling.

A constructive variant of this embodiment consists in that two molding strips 11d, 11e (FIG. 5) are provided for the device 11, specifically one (11e) thereof, seen in the direction of rotation of the gravure forme cylinder 10, before the other (11d) after the narrow gap between the gravure printing plate 1 and the application device 11. The molding 11d after the gap is positively held by a precise guide or by support jaws against the cylinder 10 at a very short distance (a few 1/100 mm) and heated to adjust the viscosity of the filling material executed so that the hydrodynamic forces are effective and a complete filling of the recesses of the basic grid is guaranteed. In addition, the rear edge of this ledge 11d is made sharp in order to ensure that the filling material is torn off cleanly from the gap. The front molding 11e is held at a greater distance from the cylinder 10 (a few 1/100 mm to a few 1/10 mm), so that the gap which becomes larger as a result is filled with material, but the hydrodynamic forces act much less strongly. The actual filling, which takes place in the area of the molding 11d, is prepared in this way and in particular by heating and pre-filling the heat-insulated raw pressure die surface.

The liquefiable substance 11 c can also be applied in excess to the gravure blank 1 in the heated state. Then, just after cooling, the excess portion is drawn off from the gravure blank 1 using a squeegee 12 that can be switched on and off, that is, scraped off and / or polished off. The doctor blade 12 can oscillate here. After the thermoplastic has cooled, the surface of the gravure blank 1 is subsequently polished in the filled state in order to set the roughness of the surface in a defined manner.

After the pictorial ablation 3 of the filled gravure blank 1, the gravure blank can be colored using a coloring system 13. A chambered doctor blade is preferably used for this, since it requires less space on the cylinder circumference than a conventional inking system and it can simply be moved away from the gravure cylinder 10 during the other method steps. During the inking, of course, the application devices 11, the doctor blade 12 and the pixel transmission unit (for example the laser 21) and other apparatus can be switched off from the gravure cylinder 10 in order to protect them from the ink and the ink mist.

Now, as in FIG. 4, it is possible to print against an impression cylinder 14 in gravure printing, but preferably in indirect gravure printing on a printing material 5. In indirect gravure printing, the printing form cylinder does not print directly on the paper, but between the printing form cylinder and the paper there is a roller covered with a smooth rubber surface. This serves as an intermediate support and thus decouples the printing form cylinder from the printing material. In conventional direct intaglio printing, two hard materials roll on one another in the printing nip between the printing form cylinder and the printing material, one of which, the printing material, also has an abrasive effect. To counteract this, hard materials are required for the printing form. In indirect gravure printing, the one printing nip is simply replaced by two, each time rolling on top of one another softly. In addition, the printing form cylinder no longer comes into direct contact with the abrasive medium paper. This allows the use of much softer materials without reducing the service life of the materials. The doctor blade, the other wearing part on the printing form cylinder, is guided through the webs made of hard material, so it does not touch the softer filling material suitable for thermal ablation either. With this measure, the service life of an intaglio printing plate manufactured in accordance with the invention is also considerably improved.

After the required edition has been printed, the gravure form is cleaned of ink residues by means of a regeneration device 15, preferably in the form of an ultrasound cleaning system, which is also designed as a system that can be turned on and off, similar to a chamber doctor blade, and the liquefiable substance from the depressions of the basic pattern of the gravure blank form 1 removed, so that the cycle (filling 2, image ablation 3, coloring 4, printing 6, regeneration 7, 8) can start again.

The ultrasonic cleaning system can be operated at at least two different levels, one level with low sound energy and / or with a liquid that only dissolves the paint, used to remove the remaining colors and the other levels with correspondingly higher sound pressures and / or other cleaning agents until the filling material is completely removed.

Another important advantage of the invention can be seen in the significantly improved quality, in particular the text reproduction, compared to conventional gravure printing. This is achieved in that the writing resolution for the imaging clearly below the distance between two webs, for. B. at 500 lines per cm. This means that text can be screened with this high resolution and much sharper letter edges can be achieved than in conventional gravure printing. In general, about 400 lines per cm are given as the lower limit for good text reproduction. The conventional gravure form production has a resolution of a maximum of 120 lines per cm and must therefore simulate sharp edges with more or less small dots, interrupted by webs, which is why gravure printing always has the so-called sawtooth effect.

In order to achieve the same number of gray levels in the image as rotogravure, which varies each point in up to 200 depth levels, a binary, ie area-variable imagesetter must be able to write at least 1000 lines per cm. The present invention now, although this binary notation is also suitable in principle, prefers a mixed form of area-variable and conventional, ie depth-variable gravure screening, the so-called hybrid screen. This grid is z. B. 500 lines per cm. However, each point can be classified in several depths. For example, if five different depths (0%, 25%, 50%, 75% and 100%) are used at 500 lines per cm writing resolution, the same halftone quality is achieved as with a writing resolution of 1000 lines per cm and only two depths (0 and 100%) or a writing resolution of 100 lines per cm and 101 different depths. Are z. B. 10 different depths used, this corresponds to the information content after 250 shades of gray at 100 lines per cm. The conversion of the available density information, which is typically available with a resolution of 256 levels, into the pattern of the hybrid screening, which is significantly less than 256 per writing point Stages, typically having about 10, takes place via the techniques of "error diffusion", dithering or stochastic screening known in prepress. All of these methods are normally used only for binary screening, but can be expanded to more than two thresholds. In particular, an image pixel can be ablated in a number of levels of different depths, which is between 2 and 256.

In order to reduce the necessary maximum depth of the indentations, which in conventional gravure printing is between 20 µm and 40 µm, highly pigmented, especially water-based inks are used. The advantages of this reduction are the lower imaging performance, which is necessary to achieve a given color density and the low water input into the paper, which accelerates the drying process considerably.

Low-pressure blank mold wear can be compensated for by the fact that the maximum imaging depth is significantly less than the depth of the depressions in the pre-structured intaglio blank. If the depth of the depressions is reduced due to the wear of the webs, the maximum depth of imaging can still be achieved for a long time. For this purpose, the webs must be designed with walls that are as vertical as possible. A narrowing of the depressions due to increasing web thickness can be compensated for in terms of process technology during exposure by determining the volume characteristic from time to time and compensating accordingly.

Various advantageous variants of measures according to the invention are conceivable. So instead of the described gravure blank with spirally attached webs, a blank with regularly arranged depressions can also be used, as they are used in a similar way to conventional shape production. The size of the wells can vary from the fine grid used today with cell sizes from 80 µm up to very large wells with z. B. 1 mm cell size or more. Instead of regularly distributed depressions, the shape can have stochastically distributed depressions in order to counteract the risk of moiré formation, in particular in multi-color printing. The random distribution can e.g. B. on the exposure of the gelatin used for a conventional etching instead of using a cross-louvre with speckles generated from coherent laser light. A wax mixed with 5% carbon black is preferably used as the filling material.

The gravure form can also be regenerated with high pressure water. For this purpose, an arrangement is used, as has already been disclosed, for example, by EP 9 310 798. Such an arrangement consists of a double-walled chamber which is open towards the gravure form and is sealed off from the surroundings by means of seals guided over the form. The inner cell contains nozzles through which the water is sprayed onto the surface of the gravure form at high pressure. It is suctioned off from the coated outer chamber area, so that the liquid is drawn off in particular from the already cleaned area and the gravure form is clean and dry after the treatment.

The high-pressure cleaner can operate at at least two different levels, one level with low liquid pressure and / or temperature essentially used to remove the remaining colors and the other levels with correspondingly higher liquid pressure and / or temperature used to partially or completely remove the filler material .

Depending on whether a basic cleaning or an intermediate cleaning should be carried out, various pressure and temperature parameters are used. If cleaning is only to be carried out from adhering dirt and paint residues, processing is carried out at a relatively low temperature in the range below 50 ° C. and a low pressure of a few bar. If basic cleaning is to be carried out, temperatures in the range of the softening or melting temperature and pressures in the range of 30 bar are used. Agents such as surfactants and particles can be added to the cleaning water to improve their effectiveness.

The depressions of the gravure blank form can also be filled via an application roller, which draws from a material reservoir and which preferably rotates in the opposite direction to the rotogravure cylinder rotation. After the application is scraped off. The angle of the doctor blade is preferably clearly negative, ie the doctor blade cuts like a knife. In particular, the doctor blade can also be heated. The gravure form can also be heated inductively before and during filling and during doctoring. The regeneration, the filling and the doctoring can preferably take place during one and the same cylinder revolution.

If thermoplastics are used, heat, e.g. B. via an infrared radiation source or hot air and materials that suck the thermoplastic from the wells by means of capillary force, z. B. a highly absorbent paper, or a blow-off or suction device.

It is also possible to clean the rotogravure form only from adhering dirt and ink without removing filler material and to refill the parts of the form removed in the previous imaging step. A complete deletion to the raw form can then take place after a predetermined number of cycles.

Furthermore, photopolymers which are hardened by laser and developed by means of water can be used as filler materials, or also varnishes which successively allow the wells to be completely filled via multiple application and intermediate drying, or the reactive systems already mentioned. The filling materials are e.g. B. sensitized by soot for the radiation used.

After filling, the surface of the gravure form can be smoothed by polishing or hot doctoring. This can also be carried out by a hot air jet or the laser beam used for image-wise ablation in low beam intensity. The latter can take place in the course of normal imaging, in that the image-free areas are irradiated with defined power, which is, however, significantly lower in relation to the image-based ablation, so that only melting takes place.

Of course, instead of one laser beam, in particular a high-energy laser beam, several beams can be used in parallel. All thermally active laser sources, such as semiconductor lasers, in particular a laser arrangement comprising a plurality of semiconductor lasers, NdYAG lasers, CO ₂ lasers, and CO lasers, can be considered as the radiation wave. For the photopolymer filling a UV or blue laser, e.g. B. be used on an argon laser. Furthermore, instead of a light source, spark erosion or a water jet can be used to remove material, e.g. B. when high resolutions are not required.

An image-wise absorbent material (e.g. blotting paper) can also be used. This procedure is explained in more detail in FIG. 6. The The basis is a multilayer film 30 '. An absorbent material 30 a (e.g. blotting paper) is applied to a non-absorbent carrier 30 b. As is customary in film cutting technology, the areas that are not required are cut out and removed using a CAD cutting plotter. The film 30 'is then brought to the gravure forme cylinder 10 previously provided with the filled blank. The film 30 'is ironed over the gravure cylinder using a heating roller 31. At the points where absorbent film material comes to rest, the filling material is then sucked out by the capillary forces; at the points that come into contact with the non-absorbent carrier, this does not happen. This enables image differentiation 32, which, however, can essentially only differentiate between full tone and paper white.

Image-wise ablation can also be performed using a micromirror array 40. The structure of such an array 40 is shown in FIG. 7. A typical representative of such an array 40 consists of individually electrically tiltable micromirrors 41, typically 20 μm × 20 μm in area, which are arranged in a matrix of 1000 × 2000 elements.

FIGS. 8 and 9 show an example of an arrangement of such an array 40 for a pixel transmission unit for imagewise ablation. The mirror relay 40 is uniformly illuminated by means of a high-energy arc lamp 42 and is imaged on the printing plate surface 44 via an optical system 43 with an imaging scale of approximately 1 such that the edge of the array 40 with the 2000 elements lies perpendicular to the direction of rotation of the forme cylinder. This edge defines the image lines. A pixel is defined as the field on which a mirror is geometrically imaged, the area of a mirror being counted towards the half of the non-imaging edge regions adjacent to the respective neighboring mirror. A mirror then reflects the energy radiated onto it onto the shape and into this pixel, if it stands so that it reflects into the solid angle that the apertures of the imaging optics dictate. The printing form cylinder rotates and 2000 image columns are written simultaneously. A mirror addresses a pixel when more than 50% of its area is mapped onto it. A line of pixels that is stationary on the cylinder travels through the lines of the mirror array 40, ie is gradually illuminated by mirror array lines of increasingly higher numbers (FIG. 9).

Suitable electronics (essentially a multi-element shift register) ensure that the image data is assigned synchronously with this migration. The image data are filled in on the first line. In synchronism with the rotation of the cylinder, the image data moves down line by line and the next line of image data is transferred to the first line. During this hike, a mirror can always be either on or off. A certain pixel can therefore receive 0 to 1000 units of energy. For example, to apply 4/10 of the maximum energy dose to a pixel, 400 mirrors are switched to "On" and 600 mirrors to "Off" during this hike while addressing the pixel. The addressing of the mirror elements 41 is therefore changed synchronously with the rotation of the gravure printing surface 44, analogously to a shift register, so that the assignment of an image pixel on the printing surface 44 with its corresponding exposure data value over the entire imaging surface of the mirror array 40 to the mold surface 44 is retained. The arrangement of the on / off mirrors is arbitrary, but may be predetermined in terms of process technology.

In principle, the image-based ablation 3 can address areas (image pixels) that are smaller than the area elements of the basic pattern of the intaglio printing blank 1, wherein in particular the image-based ablation 3 can even be carried out essentially independently of the basic pattern. However, the pictorial ablation 3 can also be adapted to the basic grid, that is to say it has a certain geometric relationship to it. In the ideal case, the image-based ablation carries out structuring of the depressions of the basic grid which is necessary in terms of process technology.

After one cylinder rotation, the print head is moved by 1000 pixels and the cycle starts again. Alternatively, the print head can be fed continuously, which moves the head by 1000 pixels in one revolution of the printing form cylinder.

The above statements all relate to the implementation of the measures according to the invention within a gravure printing press, but it goes without saying that the measures described can of course also be carried out outside a printing press.

Claims (41)

Process for rotogravure using an erasable and reusable rotogravure form, starting from a rotogravure blank with a basic grid designed at least for the maximum amount of ink to be transferred, characterized in that the depressions of the basic grid of the rotogravure blank (1) are uniformly applied by means of a liquefiable substance by an application device (11 ) are filled (2), then image-wise material is removed from the recesses by a pixel transfer device (21) (3), the image-engraved gravure form (20) is colored (4) by means of a coloring system (13) and then printed using gravure printing ( 9), finally the gravure blank (1) is regenerated after the printing process (7,8) and the depressions are filled evenly again (2). A method according to claim 1, characterized in that the liquefiable substance in the liquid state is introduced into the depressions of the basic grid of the gravure blank (1) by hydrodynamic forces, in particular by capillary action. A method according to claim 1 or 2, characterized in that the liquefiable substance is applied in excess in the liquid state to the gravure blank (1) and, after solidification, the excess portion is drawn off from the gravure blank (1) by means of a doctor blade (12). A method according to claim 1 or 2, characterized in that the liquefiable substance is applied in the liquid state to the gravure blank (1) in the same extent as the basic grid depth, in that the excess portion is drawn off from the intaglio blank (1) by means of a doctor blade (12) . Method according to Claim 4, characterized in that the basic grid of the rotogravure blank form (1) is filled completely by successive application and intermediate drying. Method according to one of the preceding claims, characterized in that the imagewise ablation (3) takes place by the action of thermal energy. Method according to one of the preceding claims, characterized in that the imagewise ablation (3) is supported by the fact that the filled gravure blank is rotated rapidly in such a way that a part of the material to be removed evaporates and a part is thrown off. Method according to one of the preceding claims, characterized in that the surface of the gravure blank form (1) is subsequently polished in the filled state. Method according to one of the preceding claims, characterized in that a chamber doctor (13) is used to ink the gravure form (20). Method according to one of the preceding claims, characterized by printing in indirect gravure printing. Method according to one of the preceding claims, characterized by the use of highly pigmented, in particular water-based, inks for coloring the gravure printing form (20). Method according to one of the preceding claims, characterized in that the regeneration (7, 8) of the gravure blank form (1), which begins with the cleaning (7) of ink residues on the gravure form (20), a complete removal of the liquefiable substance from the wells of the basic grid per cycle (filling (2), imagewise ablation (3), coloring (4), printing (6), regeneration (7, 8)). Method according to one of the preceding claims, characterized in that the regeneration (7, 8) of the gravure blank form (1) a complete removal of the liquefiable substance from the depressions of the basic grid per a predetermined number of cycles (filling (2), image-wise ablation (3), coloring (4), printing (6), regeneration (7)) and in the intervening cycles only the material of the disposable substance removed by image-wise ablation (3) is replenished. Method according to one of the preceding claims, characterized in that a thermoplastic is used for the liquefiable substance. Method according to one of the preceding claims, characterized in that photopolymers are used for the liquefiable substance. Method according to one of the preceding claims, characterized in that lacquers are used for the liquefiable substance. Method according to one of the preceding claims, characterized in that a crosslinkable polymer melt or solution (reactive systems) is used for the liquefiable substance. Method according to one of the preceding claims, characterized in that an imagewise trimmed film (30 ') is used for the imagewise ablation (3), which is ironed over the previously filled gravure blank (1) and the imagewise arranged absorbent film material (30a) Sucks the filling material in the recesses of the basic grid of the raw form (1). Method according to one of the preceding claims, characterized in that a micromirror array (40) is used for the imagewise ablation (3), which is uniformly illuminated and imaged on the gravure printing surface (44) by tiltable micromirror elements (41), the addressing of the Mirror elements (41) are changed synchronously with the rotation of the gravure form surface (44) analogously to a shift register, so that the assignment of an image pixel on the form surface (44) with its corresponding one Exposure data over the entire imaging area of the mirror array (40) on the mold surface (44) is retained. Method according to one of the preceding claims, characterized in that image pixels which are smaller than an intaglio well are addressed on the printing form surface, so that an intaglio well is generated in each case from a plurality of image pixels. A method according to claim 20, characterized in that the image pixels are ablated in a number of levels of different depths, which is between 2 and 256. A method according to claim 20, characterized in that the image-based ablation (3) addresses areas (image pixels) which are smaller than the area elements of the basic grid of the intaglio printing blank (1) and the addressing is carried out independently of the basic grid. Method according to Claim 20, characterized in that the image-based ablation (3) addresses areas (image pixels) which are smaller than the area elements of the basic screen of the intaglio printing blank (1) and are arranged in a specific geometric relationship to the basic screen. Method according to claim 20, characterized in that structurally necessary structuring of the depressions of the basic grid is carried out with the image-based ablation (3). Device for gravure printing for carrying out the method according to claim 1, characterized in that a device (11) for applying a liquefiable substance, a pixel-, to a rotating gravure blank form (1) with a basic grid designed at least for the maximum amount of ink to be transferred. Transfer device (21, 30, 40) for imagewise ablation (3) on the surface of the rotogravure plate (20), a coloring system (13) and one Regeneration device (15) for the basic grid of the intaglio printing blank (1) can be set. Apparatus according to claim 25, characterized in that the gravure blank (1) is designed as a sleeve. Apparatus according to claim 25, characterized in that for the device (11) for applying a liquefiable substance, as seen in the direction of rotation of the printing forme cylinder (10), a molding (11d, 11e) before and after the gap between the gravure blank (1) and the Device (11) is provided, wherein the molding (11d) has a sharp rear edge after the gap and is positively held against the cylinder (10) at a very short distance (a few 1/100 mm) and the molding (11e) in front of the Gap against the cylinder (10) is held at a greater distance (a few 1/100 mm to a few 1/10 mm) Gravure blank for use in the method according to claim 1, characterized in that the basic grid has webs (9) which wind helically around their cylindrical surface at a defined angle. Gravure blank for use in the method according to claim 1, characterized in that it is built up in layers, a heat-insulating layer being inserted at least between a surface layer which contains the basic grid and a carrier cylinder. Gravure blank for use in the method according to claim 29, characterized in that the heat-insulating layer consists of glass fiber reinforced carbon. Gravure blank form according to one of the preceding claims 28 to 30, the webs (9) as perpendicular as possible to characterized in that the surface of the gravure form is designed to run. Gravure blank for use in the method according to claim 1, characterized in that regular cup-shaped basic grid is provided. Gravure blank for use in the method according to claim 1, characterized in that stochastically distributed depressions are provided as the basic grid. Apparatus according to claim 25, characterized in that an ultrasonic cleaning system is provided as the regeneration device (15). Apparatus according to claim 34, characterized in that the ultrasonic cleaning system can be operated at at least two different levels, one level with low sound energy and / or with a liquid which only dissolves the paint used to remove the remaining paint and further levels for partially to complete removal of the filling material in the recesses of the basic grid. Apparatus according to claim 25, characterized in that a water high pressure high pressure cleaner is provided as the regeneration device (15). Apparatus according to claim 36, characterized in that the high pressure water cleaner can be operated at at least two different levels, one level with low liquid pressure and / or temperature serving to remove the remaining paint and the other levels with correspondingly higher liquid pressure and / or temperature for serve partial to complete removal of the filling material in the recesses of the basic grid. Apparatus according to claim 25, characterized in that a laser (21), in particular a high-energy laser , is used as the pixel transmission unit, which is intended for thermal energy. Device according to claim 38, characterized in that a semiconductor laser arrangement comprising a plurality of semiconductor lasers is provided. Apparatus according to claim 25, characterized in that an image-wise absorbent film (30) which can be ironed onto the filled basic grid of the intaglio printing blank (1) is provided as the image point transmission device. Apparatus according to claim 25, characterized in that a micromirror array (40) is provided as the pixel transmission device.

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