EP0730953B1 - Process and apparatus for intaglio printing - Google Patents

Description

The invention relates to a method and a device for gravure printing, according to the preamble of claims 1 and 15 an erasable and reusable gravure form, starting from one Gravure blank with a minimum of the maximum to be transferred Basic grid of colors.

Gravure refers to a printing process using printing elements that face each other the mold surface are lowered. After the complete coloring of the Printing form, the surface is freed from the printing ink. This only remains in the recessed positions. As a printing form z. B. copper-plated steel cylinders Clamping cores pushed on hollow cylinders or in some cases on cylinders stretched copper sheets.

The type of coloring and the blank coating of the mold surface do not allow pure surface pressure. The whole drawing must be in lines, dots or Raster elements can be resolved. Because of the different depth and size of the individual printing elements, these more or less ink, the As a result, the imprint has different positions at the different parts of the image Color strength.

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

Indentations can also be made using a high-energy laser beam , taking care that suitable measures are taken to ensure the coupling of the laser energy into the substrate, because copper for the most part uses a laser beam without special pretreatment reflected.

Furthermore, DE-OS 27 48 062 describes a method for producing a engraved printing form is known, in which only a gravure raw form is provided, by making the smooth surface even 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. On it photographically exposed the raw form with the desired image so that the polymerize exposed areas, wash out the unexposed portions can and this results in an image differentiation.

In general it can be said that the following applies to all gravure printing processes: Printing form are lower than non-image areas. Forms especially in squeegee printing the grid network of uniformly high webs, the image areas and limit one Form the contact surface for the squeegee. There is a special set of for each print job Printing form cylinders (one printing form cylinder with a corresponding one for each printing ink) Number of printed pages) required. These cylinders are in depending on the print format the required cylinder circumference. When setting up the gravure or Rotary printing presses are the corresponding printing form cylinders to replace. Such a cylinder z. B. today weighs in a width of 200 cm about 800 kg. Since the methods described so far are only outside the Printing machine are feasible, this is a high mechanical effort required. In addition, each of these manufacturing processes involves steps such as Electroplating or coating, exposure and development, which exclude that the same printing form without extensive, in particular chemical treatment can be reused. In addition, usually takes place after the pictorial Etching or engraving, i.e. removal of material, chrome plating to increase the Service life.

If the printing form is to be stored for repeat orders, this is usually the To provide space for the entire cylinder. 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.

From DE 37 39 829 A1 it is known that for the production of a gravure roll certain selected recesses selectively with a removable Material to be filled in such a way that the remaining unfilled Recesses a desired print pattern is defined. To do this, the Recesses filled with a plastic material. The desired print image is created by taking the plastic fillings out of some of the recesses removed so that they define a desired print pattern. This was achieved that the recesses defining the print pattern after the Application of the hard coating can be generated.

In contrast, DE 38 37 941 C 2 discloses a method for producing a Intaglio printing form, through which the images take place directly in the printing press can, in addition, the images of the rotogravure form deleted in the printing press and can be prepared for a new illustration. It will too a gravure blank with at least one to be transferred to the maximum Color amount of basic grid produced. Now in the printing press a nozzle of the pixel transfer unit or by image-correlated ironing a quantity of a thermoplastic which is inversely proportional to the image information Substance introduced into the well to increase the volume of the wells reduce. This means that in contrast to the imaging of a gravure blank, the other process applied image material. Can in the press then after the print job the thermoplastic substance by means of a Liquefied heat source and by means of a wiping and / or blowing or Suction device can be removed from the printing form cylinder.

The pictorial material application, however, poses problems for the position accuracy the illustration. It is not readily possible to find material on the webs is placed completely in the wells. The complete one However, it is necessary to bring in all of the transferred material desirably contributes to reducing the volume of the depressions.

Proceeding from this, the invention is therefore based on the object of a method and to develop a device of the generic type for gravure printing, which improves the positional accuracy of the imaging.

This object is achieved by the method steps of claim 1 and Device for performing the method according to claim 15 solved.

Because the cycle of the characteristic process steps is repeated warehousing of gravure forms is not necessary.

Another particular advantage of the method according to the invention and the Device for performing the method is that the Gravure raw mold wear is compensated for because the maximum imaging depth in of the substance on the rotogravure form is significantly less than that original depth of the depressions of the pre-structured raw form. That is because The depth of the depressions due to wear of the webs is smaller, nevertheless maximum imaging depth achievable for a long time. Are therefore advantageous the bars of the raw form as perpendicular to the surface of the gravure form as possible executed in progress.

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 mold 1 can thus be imaged using the method according to the invention and the device according to the invention take place directly in the printing press. The illustrated gravure form can also be easily used in the printing press deleted and prepared for a new illustration.

1 shows, a pre-structured gravure blank 1 with at least one basic grid designed for the maximum amount of color to be transferred in one first step using a liquefiable substance through an application facility filled 2. For example, a thermoplastic can be used as the substance for the filling Plastic or a wax (hot melt), varnish or a cross-linkable Polymer melt or solution, which is also referred to as a reactive system and which is characterized by an extremely high abrasion resistance. in the the surface of the gravure form is then essentially smooth. After that the filled substance by thermal energy exposure of a pixel transmission device figuratively removed from the wells 3. Now the rotogravure form can be colored 4 using a coloring system, so that on a printing material 5 can be printed in gravure 6.

After the printing process 6, the surface of the gravure form is regenerated again, by cleaning them of paint residues 7, the liquefiable substance is preferred completely detached from the pre-structured depressions 8 and the Wells are filled evenly again. The removal of the liquefied Substance from the pre-structured wells can be created using a heat source and / or blow-out or suction device.

Fig. 2 shows a pre-structured gravure blank 1 on a cylinder 10 with webs 9, which are helical with a defined angle around their cylindrical Wind the surface. The webs 9 are preferably at a distance from one another, which corresponds to the distance between today's gravure raster. For an 80s grid this would be 125 µm. However, the distance can also be significantly larger as long as the webs 9 still guide the squeegee safely without the squeegee showing any visible deflection shows and without this leading to excessive wear of the webs 9. The Gravure blank 1 is usually at least on the web surfaces wear-resistant, e.g. B. tempered with chrome or titanium oxide or is inherently very hard because made of ceramic, and / or is provided with a defined roughness so that the squeegee slides in print on a defined film of liquid.

After the depressions between the webs 9 of the gravure blank 1 with the liquefied substance in the form of a thermoplastic can then be replenished 3 by thermal energy by means of a pixel transmission device, in particular by means of a laser 21, analogous to a External drum imagesetter, the gravure printing plate 20 are burned imagewise. NdYAG or NDYLF lasers are preferably used, which have a acousto-optical modulator can be switched in several intensity levels 23. about the laser beam 22 can be guided to the intaglio printing form 1 and opened by a glass fiber optic these are focused. Care is taken that preferably a Well size of more than about 2/10 mm is not exceeded. That is called pictorial ablation 3 generates a web at the latest after approximately this distance, the is not used to guide a squeegee, but to empty it when printing to force the cell from the color. In particular, they become surfaces (Pixels) addressed that are smaller than an actual gravure well, so that a well is generated from a plurality of pixels.

Furthermore, the imagewise ablation 3 can be supported in that the filled rotogravure blank 1 is set in rapid rotation such that 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 built up in layers to achieve a low heat capacity. So is between the surface layer of a few tenths of a mm thickness, which the Basic grid of the gravure blank 1 carries, and a base cylinder heat insulating layer, e.g. B. provided from glass fiber reinforced carbon. The thermoplastic used for the liquefiable substance can also be a resin, be a synthetic or natural wax.

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

Inside a gravure printing machine is a device 11 for applying a liquefiable substance directly to a gravure cylinder 10, which the Gravure blank 1 carries, arranged adjustably. 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, the can be filled or refilled as granules. The melt 11 c is by gravity and Capillary action promoted to the surface of the gravure blank 1 and penetrates into the Depressions of the basic grid. Gravity can also by Air pressure or hydraulic pressure can be replaced by a pump. By the narrow gap between the gravure blank 1 and the application device 11 acts a capillary and hydrodynamic force that precisely conveys the amount of substance, which is needed to fill up.

A constructive variant of this embodiment is that for Device 11 two moldings 11d, 11e (Fig. 5) are provided, one (11e) thereof, viewed in the direction of rotation of the intaglio forme cylinder 10, the another (11d) after the narrow gap between the gravure form 1 and the Application device 11. The molding 11d after the gap is positive through accurate guidance or by supporting jaws against the cylinder 10 in a lot kept a small distance (a few 1/100 mm) and to adjust the viscosity of the filler material can be heated so that the hydrodynamic forces are good are effective and a complete filling of the depressions of the basic grid is guaranteed. In addition, the rear edge of this bar 11d is sharp executed to ensure the clean tearing of the filling material from the gap. The front molding 11e is at a greater distance from the cylinder 10 (some 1/100 mm to a few 1/10 mm), so that the thereby increasing Although the gap is filled with material, the hydrodynamic forces are essential look less strong. The actual filling in the area of the molding 11d takes place, in particular by heating and pre-filling the heat-insulated blank printing surface prepared.

The liquefiable substance 11 c can also be in excess in the heated state the gravure blank 1 are applied. Then just after cooling the excess portion by means of a doctor blade 12 which can be switched on and off Gravure blank 1 subtracted, that is, doctored and / or polished. The squeegee 12 can change here. Preferably after cooling the Thermoplasts the surface of the gravure blank 1 in the filled state repolished to set the roughness of the surface.

After the pictorial ablation 3 of the filled gravure blank 1, the Gravure printing form can be colored by means of a coloring system 13. Is preferred a chamber doctor blade is used for this, since it takes up less space on the cylinder circumference needed as a conventional inking system and they while the other Process steps can be easily carried out by the gravure cylinder 10. During the coloring process, the application devices 11 are, of course, the Doctor blade 12 and the pixel transfer unit (e.g. the laser 21) and others Equipment from rotogravure cylinder 10 can be switched off before the color and the Protect paint mist.

Now, as in FIG. 4, against an impression cylinder 14 in gravure printing, but preferably printed in indirect gravure on a printing material 5 become. In indirect gravure printing, the printing form cylinder does not directly on paper printed, but is located between the printing form cylinder and the paper a roller covered with a smooth rubber surface. This just serves as Intermediate carrier and thus decouples the printing form cylinder from the printing material. in the Conventional direct gravure printing rolls in the printing nip between the printing form cylinder and printing material two hard materials, one of which Substrate, also has an abrasive effect. To counteract this hard materials required for the printing form. In indirect gravure one is Pressure gap just replaced by two, each time hard on soft on each other rolls off. In addition, the printing form cylinder does not come with the abrasive medium paper more directly in touch. This allows the use of much softer ones Materials without reducing the service life of the materials. The squeegee, the other wearing part on the printing form cylinder, is due to the webs made of hard material the softer filler material suitable for thermal ablation not either. Through this measure, the service life of an additional Gravure printing plate produced according to the invention significantly improved.

After the required edition has been printed, the rotogravure plate is printed using a Regeneration device 15, preferably in the form of a Ultrasonic cleaning system, also as an on and off system is similar to a chambered doctor blade, cleaned of paint residues and the liquefiable substance from the depressions of the basic grid of Gravure blank 1 removed so that the cycle (filling 2, imagewise ablation 3, Coloring 4, printing 6, regeneration 7, 8) can begin again.

The ultrasonic cleaning system is on at least two different levels operable, a level with low sound energy and / or with a Liquid that only dissolves the color, serves to remove the remaining colors and the other levels with correspondingly higher sound pressures and / or others Cleaning agents for the partial to complete removal of the filling material serve.

Another important advantage of the invention is that over the conventional Gravure significantly improved quality, especially text reproduction see. This is achieved in that the write resolution for the imaging well below the distance between two webs, e.g. B. at 500 lines per cm. In order to text can be screened at this high resolution and it is essential to achieve sharper letter edges than in conventional gravure printing. In general, around 400 lines per cm are a good lower limit Text reproduction specified. Conventional gravure mold making has one Resolution of up to 120 lines per cm and must therefore have sharp edges more or less small dots, interrupted by bars, simulate why Gravure printing always has the so-called sawtooth effect.

To achieve the same number of gray levels in the image as the gravure printing Varies every point in up to 200 depth levels, a binary, i.e. H. variable area working imagesetter can write at least 1000 lines per cm. The The present invention now prefers, although this binary notation in principle is also suitable to use a mixed form of area-variable and conventional, i.e. H. variable-depth gravure screening, the so-called hybrid screen. This grid is with z. B. 500 lines per cm. However, any point here can be in several depths. For example, at 500 lines per cm Write resolution five different depths (0%, 25%, 50%, 75% and 100%) used, the same halftone quality is achieved as with a write resolution of 1000 lines per cm and only two depths (0 and 100%) or one Writing resolution of 100 lines per cm and 101 different depths. Become e.g. B. 10 different depths used, this corresponds to the information content after 250 shades of gray at 100 lines per cm. Conversion of the present Density information, which is typically available with a resolution of 256 levels, into the pattern of hybrid screening, which is significantly less than 256 per writing point Stages, typically about 10, takes place in the prepress known techniques of "error diffusion", dithering or stochastic Grid. All of these methods are normally used only for binary screening used, but can be expanded to more than two thresholds. In particular, can an image pixel is ablated in a number of levels of different depths is between 2 and 256.

In order to reduce the necessary maximum depth of the depressions, that of the conventional Gravure printing is between 20 µm and 40 µm, are highly pigmented, in particular water-based paints used. The advantages of this reduction are: lower imaging performance, which is necessary to achieve a given color density reach and the low water input into the paper which is drying significantly accelerated.

The low pressure raw form wear can be compensated for by the fact that the maximum Depth of imaging is significantly less than the depth of the depressions in the pre-structured gravure blank. Now the depth of the wells is through The wear on the webs is less, but the maximum imaging depth is still long reachable. For this purpose, the webs must be closed with walls that are as vertical as possible shape. A narrowing of the depressions due to increasing web thickness can be technically compensated for the exposure by the Volume characteristic is determined from time to time and compensated accordingly.

There are various advantageous variants of measures according to the invention conceivable. So instead of the described gravure blank with spiral attached bars also a raw form with regularly arranged depressions can be used as it is used similarly in conventional shape creation become. The size of the wells can vary from those used today Fine screens with cell sizes from 80 µm up to very large in area Wells with z. B. 1 mm cell size or more. The shape can be regular instead distributed depressions have stochastically distributed depressions to avoid the danger to counteract the formation of moiré, especially in multi-color printing. The Random distribution can e.g. B. on the exposure of a conventional etching used gelatin instead of a cross-louvre with out of coherent laser light generated speckles are produced. A is preferably used as the filling material wax mixed with 5% soot is used.

The gravure form can also be regenerated with high pressure water become. For this purpose, an arrangement is used, such as that already used by EP 9 310 798 has been disclosed. Such an arrangement consists of a double-walled chamber, which is open to the gravure form and by means of the form guided seals is sealed off from the environment. The inner cell includes nozzles through which the water with high pressure on the surface of the Gravure form is sprayed. The encased outer chamber area becomes suctioned off, so that the liquid in particular from the already cleaned area is pulled off and the gravure form is clean and dry after the treatment.

The pressure washer can work on at least two different levels, a level with low fluid pressure and / or temperature in Mainly used to remove the remaining colors and the other levels with a correspondingly higher liquid pressure and / or temperature, sometimes up to complete removal of the filler.

Depending on whether a basic cleaning or an intermediate cleaning is carried out different pressure and temperature parameters are used brought. Should only cleaning of adhering dirt and paint residues take place with a relatively low temperature in the range below 50 ° C. and low Processed 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 can use the cleaning water how surfactants and particles are added to improve effectiveness.

The deepening of the gravure blank form can also be filled via a Application roller take place, which draws from a material reservoir and which favors rotates counter to the rotogravure cylinder rotation. After the request is made doctored. The angle of the doctor blade is preferably clearly negative, i. H. the squeegee cuts like a knife. In particular, the doctor blade can also be heated. Also the Gravure form can be used before and during filling and during doctoring be heated inductively. The regeneration, filling and doctoring can preferably done during one and the same cylinder revolution.

If thermoplastics are used, heat, e.g. B. via a Infrared radiation source or hot air and materials by means of capillary action suck the thermoplastic from the wells, e.g. B. a highly absorbent Paper, or a blow-off or suction device can be worked.

It is also possible to clean the gravure form only from adhering dirt and color without filling material removal and a refill of the at previous imaging step removed portions of the mold. A complete extinction for 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, used, or varnishes that over multiple application and intermediate drying successively complete filling of the Permit deepening, or just the reactive systems already mentioned. The Filling materials are e.g. B. by soot entry for the radiation used sensitized.

The surface of the gravure form can be polished or filled after filling Hot doctor blades are smoothed. This can also be a hot air jet, or for the Imaging ablation take over the laser beam used in low beam intensity. The latter can be done in the course of normal imaging, using the non-image Places with defined, but essential in relation to the pictorial ablation lower power are irradiated 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 composed of a plurality of semiconductor lasers, NdYAG lasers, CO ₂ lasers and CO lasers, are suitable 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.

Likewise, an image-wise, absorbent material (e.g. blotting paper) 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. Like in the Foil cutting technology is not common with a CAD cutting plotter needed areas cut and removed. The film 30 'is then to the brought previously with the filled blank mold gravure cylinder 10. By means of a heating roller 31, the film 30 'over the gravure cylinder ironed. At the places where absorbent foil material is lying, the filling material is then sucked out by the capillary forces at the points that do not come into contact with the non-absorbent carrier. This allows an image differentiation 32, which, however, is essentially only can differentiate between solid 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 Such an array 40 consists of individually electrically tiltable micromirrors 41 of typically 20 µm x 20 µm area, in a matrix of 1000 x 2000 Elements are arranged.

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 illuminated uniformly by means of a high-energy arc lamp 42 and via a Optics 43 with an image scale of approx. 1 onto the printing form surface 44 see above shown that the edge of the array 40 with the 2000 elements perpendicular to Direction of rotation of the forme cylinder lies. This edge defines the image lines. On Pixel is defined as the field on which a mirror is geometrically mapped is, with the surface of a mirror in each case the half adjacent to it not imaging edge areas is calculated up to the respective neighboring mirror. On Spiegel then reflects the energy radiated onto it onto and into the form Pixel, if it stands so that it reflects in the solid angle, which the aperture of the Specify imaging optics. The printing form cylinder rotates and there are 2000 each Image columns written at the same time. A mirror addresses a pixel if more than 50% of its area is mapped on this. One on the cylinder The stationary line of pixels travels through the lines of the mirror array 40, i. H. is gradually illuminated by mirror array lines of ever higher numbers (Fig. 9).

Suitable electronics (essentially a multi-element shift register) ensure for a synchronous assignment of the image data for this hike. The image data are filled in on the first line. Synchronous to the rotation of the cylinder the image data moves down line by line and the next line from Image data is transferred to the first line. During this hike, a Mirror should always be either on or off. A certain pixel can so get 0 to 1000 units of energy. For example, a pixel with 4/10 to apply the maximum energy dose, 400 mirrors during this hike to "On" and 600 mirrors to "Off" while they are on Address pixels. The addressing of the mirror elements 41 is therefore synchronized with the rotation of the rotogravure mold surface 44 is changed analogously to a shift register, so that the association of an image pixel on the printing form surface 44 with its corresponding exposure data value over the entire imaging area of the Mirror arrays 40 on the mold surface 44 are retained. The arrangement of the The on / off mirror is arbitrary, but may be specified in terms of process technology.

In principle, 3 areas (image pixels) can be addressed by the image-based ablation that are smaller than the surface elements of the basic grid of the gravure blank 1, in particular the imaginary ablation 3 even essentially can be carried out independently of the basic grid. However, the pictorial Ablation 3 is also adapted to the basic grid, that is to say in a certain one geometric relation to it. Ideally, the pictorial leads Ablation structurally necessary structuring of the wells of the Basic grid through.

After one cylinder rotation, the print head is moved by 1000 pixels and the Cycle starts again. Alternatively, a continuous feed can also be used of the printhead, the head in one revolution of the printing form cylinder shifted by 1000 pixels.

The above statements all relate to the implementation of the measures according to the invention within a gravure printing press, it understands however, that the measures described are of course also outside a printing press are feasible.

Claims (31)

1. Process for intaglio printing by means of an erasable and re-usable intaglio forme, proceeding from a blank intaglio forme having a base screen designed at least for the maximum amount of ink to be transferred, characterised in that within the intaglio machine the depressions of the base screen of the blank intaglio forme (1) are each uniformly filled (2) by means of a liquefiable substance by an application device (11), material is then removed image-wise from the depressions by means of a pixel-transfer device (21), whereby surfaces (pixels) which are smaller than the surface elements of the base screen of the crude intaglio forme (1) are addressed, the intaglio forme (20) screened image-wise is inked (4) by means of an inking system (13) in the form of a chambered doctor blade,
   and is then printed (9) in intaglio,
   finally the crude intaglio forme (1) is regenerated (7, 8) after the printing procedure and the depressions are again uniformly filled (2).
2. Process according to claim 1, characterised in that an excess of the liquefiable substance in the liquid state is applied to the blank intaglio forme (1) and after hardening the excess amount is removed from the blank intaglio forme (1) by means of a doctor blade (12) .
3. Process according to claim 1, characterised in that the complete filling of the base screen of the blank intaglio forme (1) is effected by successive multiple application and intermediate drying.
4. Process according to claim 1, characterised in that the image-wise ablation (3) is effected by thermal energy.
5. Process according to claim 1, characterised in that the surface of the blank intaglio forme (1) in the filled state is subsequently polished.
6. Process according to claim 1, characterised by printing in indirect intaglio.
7. Process according to claim 1, characterised by the use of highly pigmented, in particular water-based inks for inking the intaglio forme (20).
8. Process according to claim 1, characterised in that the regeneration (7, 8) of the intaglio forme (1), which begins with the cleaning (7) of ink residue on the intaglio forme (20), includes the complete removal of the liquefiable substance from the depressions of the basic screen per cycle with filling (2), image-wise ablation (3), inking (4), printing (6) and regeneration (7, 8).
9. Process according to claim 1, characterised in that the regeneration (7, 8) of the blank intaglio forme (1) provides for the complete removal of the liquefiable substance from the depressions of the basic screen every predetermined number of cycles with filling (2), image-wise ablation (3), inking (4), printing (6) and regeneration (7), and in the intermediate cycles only the material of the liquefiable substance removed by the image-wise ablation (3) is filled up again.
10. Process according to claim 1, characterised in that a thermoplast is used for the liquefiable substance.
11. Process according to claim 1, characterised in that photopolymers are used for the liquefiable substance.
12. Process according to claim 1, characterised in that lacquers are used for the liquefiable substance.
13. Process according to claim 1, characterised in that for the image-wise ablation (3) a micro-mirror arrangement (40) is used which is uniformly illuminated and reproduced on the intaglio forme surface (44) with image elements by tiltable micro-mirror elements (41), the addressing of the mirror elements (41) being changed synchronously with the rotation of the intaglio forme surface (44) similarly to a shift register, so that the association of a pixel on the printing forme surface (44) with its corresponding illumination data value is retained over the entire imaging surface of the mirror arrangement (40) onto the forme surface (44).
14. Process according to claim 1, characterised in that structuring of the depressions of the basic screen, necessary from the point of view of the technical procedure, are carried out with the image-wise ablation (3).
15. Apparatus for intaglio printing for carrying out the process of claim 1, characterised in that onto a blank intaglio forme (1) rotating in the printing machine, having a base screen in the circumferential direction designed at least for the maximum amount of ink to be transferred, there can be set a device (11) for applying a liquefiable substance, a pixel-transfer device (21, 30, 40) for image-wise ablation (3) on the surface of the intaglio forme (20), an inking system (13) in the form of a chambered doctor blade, and a regeneration device (15) for the basic screen of the blank intaglio forme (1).
16. Apparatus according to claim 15, characterised in that the blank intaglio forme (1) is designed as a sleeve.
17. Apparatus according to claim 15, characterised in that for the device (11) for applying a liquefiable substance, seen in the direction of rotation of the printing forme cylinder (10), there is provided a moulded strip (11d, 11e) before and after the gap between the blank intaglio forme (1) and the device (11), the moulded strip (11d) after the gap having an acute rear angle and is held in a form-fitting manner against the cylinder (10) with a very small spacing of a few 1/100 mm, and the moulded strip (11e) before the gap is held against the cylinder (10) with a greater spacing of some 1/100 mm to a few 1/10 mm.
18. Apparatus according to claim 15, characterised in that the base screen of the blank intaglio forme (1) has crosspieces (9) which wind in a screw-like manner at a specific angle about its cylindrical surface.
19. Apparatus according to claim 15, characterised in that the blank intaglio forme (1) is of layered construction, wherein a heat-insulating layer is inserted at least between a surface layer, containing the base screen, and a carrier cylinder.
20. Apparatus according to claim 19, characterised in that the heat-insulating layer is made of glass-fibre-reinforced carbon.
21. Apparatus according to one of the preceding claims 18 to 20, characterised in that the crosspieces (9) are designed to extend as perpendicularly as possible to the surface of the intaglio forme.
22. Apparatus according to claim 15, characterised in that a uniform cell-like base screen is provided.
23. Apparatus according to claim 15, characterised in that randomly distributed depressions are provided as the base screen.
24. Apparatus according to claim 15, characterised in that an ultrasonic cleaning device is provided as the regeneration device (15).
25. Apparatus according to claim 24, characterised in that the ultrasonic cleaning device can be operated at least two different levels, wherein one level with low sound energy and/or with a liquid which only dissolves the ink, is used to remove the remaining ink, and other levels are used for the partial to complete removal of the filling material in the depressions of the basic screen.
26. Apparatus according to claim 15, characterised in that a high-pressure water cleaner is provided as the regeneration device (15).
27. Apparatus according to claim 26, characterised in that the high-pressure water cleaner can be operated at least two different levels, wherein one level with low liquid pressure and/or temperature is used to remove the remaining ink, and the other levels with correspondingly higher liquid pressure and/or temperature are used for the partial to complete removal of the filling material in the depressions of the basic screen.
28. Apparatus according to claim 15, characterised in that a laser (21), in particular a high-energy laser, provided for thermal energy input, is used as the pixel-transfer unit.
29. Apparatus according to claim 28, characterised in that a semi-conductor laser arrangement comprising several semi-conductor lasers is provided.
30. Apparatus according to claim 15, characterised in that an absorbent foil (30) which can be ironed onto the filled base screen of the blank intaglio forme (1), cut according to the image, is provided as the pixel-transfer device.
31. Apparatus according to claim 15, characterised in that a micro-mirror arrangement (40) is provided as the pixel-transfer device.

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