Pad printing system and method for it

Description

Field of the invention

[0001] The present invention relates to a combined transfer printing system for printing objects, via an intermediate carrier of the pad type, consisting of a pad-based transfer system for media to be transferred by a pad having an ink take-up and deposition axis, wherein it consists of an indexed linear pad printing system with rotation of a rotary disc about an axis of the device which is parallel to the ink take-up and deposition axis.Background of the invention

[0002] In traditional linear pad printing, the inking is obtained by a to and from motion of the printing plate, wherein ink is left in the engraving. The ink is then taken up by a pad or similar. In a final phase, the image is deposited onto the product. An alternative method consists in the printing plate being rotated about an axis perpendicular to the plane of the flat printing plate. In both cases, the inking and the take-up of the ink takes place in a different motional state of the printing plate, namely in motion for the inking and at absolute standstill during take-up of the ink.

[0003] In rotary systems, inking is carried out continuously and ink is continuously taken up by an inked engraved roller and continuously deposited -the actual printing- onto the product(s). As a result of the rotary nature of the motion during take-up and depositing of the ink, in the case of non-developable surfaces, a form of slip inevitably occurs between pad roller and printing plate and / or pad roller and product. This does not benefit the print quality, so that, inter alia, four-colour printing is difficult or even impossible, due to the photorealistic quality.

[0004] The present description leans closely on these existing technologies, namely traditional linear pad printing; rotary printing, wherein a cylindrical printing roller is permanently inked and wherein a cylindrical pad roller takes up the image from the printing plate and then rolls down the product; and, finally, the indexed inking system, wherein movement and standstill of at least a part of the inking system each have a function within the cycle, via a so-called endless ink carrier such as a flat disc, and an indexed take-up and depositing of the ink.Prior art

[0005] In traditional linear pad printing as illustrated by Fig. 1, the working principle is as follows: a pad takes up ink from a printing plate at position A by movement along an axis. For take-up of the image by the pad, the printing plate is inked, wherein the doctoring motion of the ink reservoir with doctoring system that leaves ink in the engraving takes place perpendicular to the axis. Following take-up of the image, the pad is brought into a fixed position B with respect to the product. The desired image is deposited via the pad onto the object to be printed, by movement along the axis. Following the depositing of the image onto the product, the pad is optionally cleaned with the aid of a pad wiping system: to this end, the pad is brought by movement along the axis into contact with the cleaning tape, whereupon the ink left on the pad is removed.

[0006] This system of pad printing offers a limited speed as a result of the decoupling of inking, with movement along an axis 8, and take-up of an image 4, by movement along an axis 7a, on the printing plate 2, and depositing, by movement along an axis 7b, of the ink onto the product 5.

[0007] This limitation can partially be negated by simultaneously taking up ink from the printing plate and depositing it on the product, by means of extra movements and the pad. In any event, the limitation of take-up and depositing immobility during doctoring motion persists, resulting in the inherent speed limitation.

[0008] In traditional rotary pad printing as illustrated by Fig. 2, the working principle is as follows: a pad roller 1, rotating about its axis according to a rotary motion 7, takes ink 4 at fixed positions A from a printing roller 2 which rotates about its axis, lying parallel to the axis about which the pad roller rotates, according to a rotary motion 8. The printing roller 2 rotates in synchronization with the pad roller 1, such that the momentary speeds of the peripheries of the printing plate 2 and pad roller 1 are equal. Following the depositing of the image onto the product 5, the pad 1 is optionally cleaned with the aid of a pad wiping system 6: to this end, the pad 1 is dampened with ink or a liquid cleaning agent and subsequently scraped, whereupon all the liquid left on the pad is removed. Though this system offers high capacities, in particular printing speeds, it also offers lower print quality through the effect of slip. The degree of slip is influenced by a combination of factors, such as the size of the printing, geometry and surface properties of the print surface and the movement of the product.

[0009] There is also a limitation as regards possible shapes. In an indexed inking system using an endless ink carrier and an indexed take-up and depositing of the ink as illustrated by Fig. 3, the working principle is analogous to the linear pad printing system, with the difference that ink is applied to the image carrier by a rotary motion 8 of the printing plate 2 about an axis parallel with the axis of take-up and depositing of the ink 7a and 7b, and thus perpendicular to the surface of the image carrier 2. The printing system can be set up both horizontally and vertically by means of the precise facilities for guaranteed inking. This system of pad printing, too, offers limited speed, as a result of the decoupling of take-up of ink 4 onto the printing plate 2 and depositing of the ink onto the product 3.

[0010] It is clear from the above that the prior art has problems and deficiencies, including in connection with the capacity, in particular speed, in relation to print quality. None of the previous systems combine high print quality, in particular photorealistic print quality, with high capacity, in particular speed. This is a problem inherent to the existing technologies, and is present under all possible conditions. Either a high print quality is achieved for all surfaces and geometries, subject to the necessary know-how, in which case, however, there are so-called dead times in the printing process, in other words inertia, or there are no dead times in the printing process but loss of quality, in particular owing to the presence of slip, in the printing, insofar as the surface is to be printed via rotary motion. Only simple geometries can be printed via rotary printing.

[0011] In each of these cases, moreover, the doctoring speed is limited. The reference value for traditional linear pad printing is deemed to be 4000 cycles / h, and for traditional rotary pad printing 25 to 40 m / min.

[0012] In terms of geometries, especially simple as opposed to complex geometries, virtually any geometry can be printed via linear pad printing, subject to the necessary know-how. This relates to both convex and slightly concave surfaces which can be printed in one or more printing steps. However, where printing consisting in depositing the image onto the product is carried out via rolling, wherein, for example, pad roller and product move relative to each other with a rotary motion, then this is virtually impossible for surfaces which are not developable surfaces. This is a serious limitation with regard to the usability of this technology.

[0013] Reference is also made here to pad printing systems comprising a particular doctoring system, in particular with double doctor blade.

[0014] Remedying to the above-stated limitations implies a technological solution which is not achieved by devices implementing the traditional method of pad printing, thereby notably including the teachings of document WO 86 / 04019 A1 of Tampoflex which discloses a device and a method for printing workpieces using tampons, printing blocks and supports for the workpieces to be printed, which are fixed in the supports. The tampons, blocks and workpieces are synchronized in their displacements along closed paths. The respective paths of the tampons and blocks are partially mutually parallel, and likewise between tampon and workpiece paths resp. The corresponding portions are displaced in the same direction, and the tampons are displaced in turn perpendicularly thereon to take the image with an inked block for transmitting the image to a workpiece.

[0015] EP0544176A1 of Binnen G. discloses a multicolour pad printing machine, in which a cross-shaped pad carrier is rotatable about a first axis and a printing-block carrier is rotatable in synchronism with the pad carrier about a second axis parallel to the first axis and having a plurality of colour printing blocks. Corresponding printing-block colour pots are disposed in such an arrangement that the printing-block surface on the printing-block carrier, a printing-material mounting and a pad-cleaning device are arranged circularly about the pad carrier in one plane, whilst, with the printing material retained immovably, a respective first pad receives the printing image from the colour printing block assigned to it. At the same time, the pad preceding this first pad prints its printing image onto the printing material, and a pad following the first pad is cleaned by the cleaning device. This operation takes place cyclically, until all the pads have transferred the respective colour printing image onto the printing material.

[0016] DE8808059U1 of Morlock Mechanik GmbH discloses an inking device for pad printing machines for applying color to a cliché. In order to eliminate difficulties occurring when paint dries up on the walls of a container this requires to remove dried paint before restarting the printing machine, and to design a hollow body in such a way that color solidifications no longer occur. Therefor, the hollow body has two downwardly open, self-contained chambers, one of which is provided with a paint supply and discharge. Paint is thus exchanged in the chamber, which has both a paint supply and a paint drain thus preventing a solidification process in the chamber area. An inner chamber is arranged within an outer chamber formed by the walls of the hollow body, wherein the inner chamber has the paint supply and discharge, the outer chamber having at least one paint discharge.Aim of the invention

[0017] The object consists in overcoming the shortcomings of the latter prior art and avoiding the drawbacks and rectifying the same.

[0018] To this end, one or more of the following measures should be taken as the solution to the problems and deficiencies of the current systems, in dependence on a number of specific parameters.Summary of the invention

[0019] There is thus proposed according to the invention an adapted printing system, as defined below in claim 1, wherein the aimed object is achieved by means of an adapted device thanks to the invention, wherein the advantages of both technologies are combined in a remarkable manner, namely a continuous printing process comprising inking, image take-up and image depositing, the printing plate being continuously in motion, on the one hand, and offering a high printing quality with, inter alia, the prospect of four-colour printing, on the other hand.

[0020] An application which can be adopted as reference is the printing of caps for bottles or other containers in one or more colours, both on the essentially flat top surface and on the essentially cylindrical side edge of the cap: it is therefore possible to obtain, with the quality of linear pad printing, a speed of 40,000, 80,000, 120,000 or even more printed caps per hour, both for top printing and periphery printing of the caps, with a photorealistic print quality. Besides this application, there are also a number of other applications according to the same invention.

[0021] For the sake of simplicity, reference is made hereinafter essentially to inking, which should also be understood, however, as the application of other mediums, such as varnish, glue, conducting paste, thermoplastics.

[0022] It is thus proposed according to the invention a device for printing products via an intermediate carrier, consisting of the pad type as defined in claim 1. A correspondent method is provided in claim 7, whilst further preferred embodiments of the invention are defined in the dependent claims.

[0023] Thanks to these embodiments indicating the core of the invention, there is achieved : a continuous motion of the image carrier, with printing of an image to be applied to the product by means of a printing medium such as ink, but also varnish, glue, conducting paste, thermoplastics, during the motion, and continuous motion (synchronized with the previous motion) of a pad-based image transfer system, and continuous motion (synchronized with the previous motion) of the product(s) to be printed. Thus, by virtue of the combined system as proposed according to the invention, both a high speed and a qualitative transfer are obtained. Moreover, a very good positioning of the products is achieved.

[0024] For printing products via an intermediate carrier through a pad with a device according to the invention wherein a pad printing system is operated for printing products, a printing medium such as ink, varnish, adhesive, conductive paste, thermoplastics, can be transferred to the product through said pad, by performing a combined linear and rotary intermediate printing through pad printing, wherein the transfer quality of linear pad printing is accomplished with the speed of rotary pad printing or offset, wherein the transfer of medium operates without slip.

[0025] As a result of this method, optimal printing is obtained.

[0026] The measures proposed according to the invention which constitute the solution to the problems and deficiencies of the current methods of the prior art identified above are set out below with reference to the finding that the pad printing method proposed thanks to the invention is founded on changes in surface tension during the various steps: inking of the ink carrier, take-up of the ink from the ink carrier, in particular the printing plate, by means of an intermediate carrier, i.e. a pad, and depositing of the ink from the pad onto the product. This also applies to any other form of transfer of a printing medium such as varnish, glue, conducting paste or thermoplastics.

[0027] Further details and particularities of the invention are set out with reference to the following description of an illustrative embodiment of the device, or method of the invention for both these last, with the aid of the appended drawings, in which the same reference numerals relate to the same or analogous elements.Brief description of the drawings

[0028] Fig. 1 set out above is a basic representation of a classical linear pad priniting system. Fig. 2 set out above as well shows a further basic representation of a classical rotary pad priniting system. Fig. 3 equally set out above is a still further basic representation, yet of an indexed linear pad priniting system with a cliché rotating about an axis being parallel to an ink taking-up resp. depositing axis by means of a pad. Fig. 4 shows a basic representation of an implementation of the invention with rotating disc; and Fig. 5 shows a basic representation of an implementation with endless belt respectively, not belonging to the invention. Fig. 6 shows a basic representation of an additional embodiment. Fig. 7-10 illustrate schematically the various phases of the inking of a printing plate in a method and device comprising possible embodiments of doctor blades according to the invention. Description

[0029] In general terms, the present invention relates to a system, inter alia having one colour of printing medium such as ink, or else varnish, glue, conducting paste or thermoplastics.

[0030] Figure 4 represents a system having a plurality of colours, especially ink, varnish, glue, conducting paste or thermoplastics, for which various alternatives have been devised. In a first embodiment, a plurality of single-colour systems are placed one after another. The products 5 here need to be correctly positioned during the application of the various colours.

[0031] In a non-claimed embodiment, the images for the various colours are placed on the same endless belt in such a way that the images stand side by side when viewed in the motional direction of the endless belt. The inking systems are consequently placed side by side such that, during the motion of the belt, a trail of images per colour, as it were, is obtained. Use is made here of pads 14, which are positioned with respect to these various trails. There is no fundamental difference between embodiments in which the pads are displaceable in the transverse direction, those in which the products are displaceable in the transverse direction, or those having a combination of transverse displacement of pads and products.

[0032] The most important thing is that, during the depositing of the image onto the product, the pads 14 are correctly positioned with respect to the product 18. As a result, printing in several colours on several positions of the product is possible. This method results in a reduction of the printing speed, since the images are taken up and deposited one after another. The abovementioned advantages over traditional and rotary pad printing are nevertheless maintained.

[0033] With an endless belt for inking, images are placed on the endless belt for a particular embodiment at predefined places. To enable the images to be correctly positioned with respect to the pads and the products with each revolution, it is necessary for the endless belts to move in a zone-synchronous manner: zone image on the printing plate synchronous with zone pad, synchronous with zone product. To this end, traditional electromechanical techniques can be used.

[0034] With an endless belt of pads, pads can assume different shapes.

[0035] Traditionally, in the case of pad printing, a predefined image is taken up from the printing plate and transferred to the product. It is also possible, however, that the pad, for example consisting of an inked solid, selectively takes up the image to be printed: indirect gravure printing. An embodiment of this limit case also falls under the protection of the invention.

[0036] Figure 4 shows a basic representation of an embodiment of the invention with a rotating disc in the form of a round disc. A circular printing plate 3 is inked, by rotation about the principal axis ℓ, by means of a fixedly mounted inkpot 6. Products 5 and pads 4 are synchronized in rotation about the same principal axis ℓ by a physical coupling. The vertical take-up motion of the pads 4 is obtained by the movement of a reference point from the pads via a cam system into a cam 9, for example oval with vertical and horizontal grooves. During the cycle of a rotation about the principal axis, both the vertical motion -down and up- for take-up of the image on the printing plate 3, and the vertical motion for the depositing of the image onto the product 5 are realized. The products 5 move along a circular path concentric with the printing plate 3 along the principal axis.

[0037] In order both to take up the image from the printing plate 3 and deposit the received image onto the product 5 with the same pad 4, the pad must be able to move to and from between the two concentric paths. The horizontal motion, with horizontal sliding system 7 for the same, is obtained by movement of a reference point from the pad via a cam system into the cam 9. Within the cycle of 1 rotation, the product 5 must be placed onto the concentric path and removed again.

[0038] Fig. 5 shows an endless belt in the form of a conveyor belt. A printing plate 12 realized as a conveyor belt is inked, by rotation of the conveyor belt, by means of a fixedly mounted inkpot 11. Products 18 and pads 14 are synchronized through the engagement of the gearwheel 15 in the product-conveyor belt 19. The vertical motion of the pads during take-up and depositing of the image is obtained by moving a reference point from the pads along a cam system into a cam 16. During the cycle of a rotation of the conveyor belt 19, both the vertical motion -down and up- for take-up of the image onto the printing plate 13 and the vertical motion for the depositing of the image onto the product are realized. The products 18 move along a linear path parallel with the pads. The product 18 must be placed onto the conveyor belt 19 and removed again, preferably outside of the zone for the depositing of the image.

[0039] The working of the system is described below in its 4 phases.

[0040] In phase 1, of inking, the endless belt is continuously inked. A number of embodiments are differentiated: the endless and continuously rotating belt is continuously inked via a traditional open or closed ink system known from pad printing; the images are applied into the belt as a recess in which the ink can be left during the doctoring process, and these are located at predefined places on the endless belt; these images are applied by means of a method outside of the production process, especially the printing.

[0041] The endless and continuously rotating belt is continuously inked via a traditional open or closed ink system known from pad printing; the images are applied into the belt as a recess in which the ink can be left during the doctoring process, and these are located at predefined places on the endless belt; these images are applied during the production process for inking and printing with an, as it were, digital image generation system.

[0042] The endless belt is inked via a digital ink system, which during its continuous motion applies the ink to the predefined places; over its total length or limited to predefined zones, the belt is construed as a carrier, to which ink can temporarily be applied and from which the ink can be taken up and transferred to a temporary intermediate carrier or, where appropriate, even the product.

[0043] Phase 2 is that of ink take-up, wherein the endless belt is continuously inked with images as described in the above. In traditional linear printing, the linear axis 7a of a pad is then moved in synchronization with the image to be transferred. To this end, the pad(s) is / are fastened to a second endless belt, which is moved in synchronization with the first ink carrier. During this motion, the pad is moved according to a linear movement along the axis 7a, whereupon the image is taken up onto the temporary carrier, in particular the pad. During this motion, the relative motion of the pad with respect to the ink carrier is purely linear.

[0044] In traditional rotary printing, the pad is then moved in synchronization with the image to be transferred. To this end, the pad(s) is / are fastened to a second endless belt, which is moved in synchronization with the first ink carrier. Two cases can arise: involving the use of a pad having a developable surface, in particular a cylindrical pad or a segment thereof; the speed of the endless belt to which the pad(s) is / are fastened is necessarily less than the doctoring speed of the endless ink carrier, taking account of the relative motion of the pad about its rotational axis, transversely to the doctoring direction. Or involving the use of a pad which is not a developable surface; the method of take-up of the ink is analogous to the process in the case of traditional linear printing as described earlier.

[0045] Phase 3 is that of positioning of the pad with respect to the product: following take-up of the image according to the preceding description, each pad is transported according to the endless belt, which positions the pad(s) in a synchronized manner with respect to the product(s) which is / are mounted on a third endless belt. Here, account must also be taken of the positioning of the pad with respect to the product in the motional direction of the endless belt on which the products are connected, in the transverse direction hereto and in rotation. In particular, it is also possible to apply prints in several colours to different places on the product.

[0046] Phase 4 is that of ink depositing. In traditional linear printing, the motions of the endless belts of pads and products are synchronized such that, in the event of movement along the axis 7a, the resulting relative motion between pad and product is purely linear.

[0047] In traditional rotary printing, two cases can arise: involving the use of a pad having a developable ruled surface, in particular a cylindrical pad or a segment thereof; the speed of the endless belt to which each pad is fastened can be less than the speed of the endless belt bearing the products, taking account of the relative motion of the pad about its rotational axis, transversely to the doctoring direction. Or involving the use of a pad which is not a developable ruled surface; the method of depositing of the ink is analogous to the process in the case of traditional linear printing as described earlier.

[0048] The cycle according to the said phases occurs in parallel for the various pads and products to be printed.

[0049] Here, the focus has been on the printing of complex convex and concave objects. It should be clearly understood, however, that not only complex, but also simple surfaces, such as developable surfaces including cylinders and cones can be printed with this technology. Examples are the top and the periphery of caps of bottles or other containers, such as syringes. According to one embodiment, the top and periphery of such caps could be printed at high speed with high-value photorealistic images with one and the same machine.

[0050] Fig. 6 shows the additional embodiment consisting, inter alia, of the following elements: an ink system A, a cleaning doctoring system B with the aid of ink or cleaning product, especially solvent, a doctor blade C, an air knife D, pads on a guide E and product on a product transport system F. With regard to the industrializability of the device, the following is of primary importance: quality of the printing and repetitivity and continuity of the quality of the printing in an industrial environment. The quality of the printing is dependent on a number of factors, including the system of inking and the system of transfer.

[0051] In the case of inking via a doctoring system with closed chamber, it is ensured that the doctoring involves an only limited impression force on the printing plate. High impression force of the closed ink system on the printing plate produces, after all, large friction forces which negatively influence the mechanical strength and stability and the required drive. In addition, with increasing friction force and increasing doctoring speed, the heat development increases, resulting possibly in additional drying-out effects, namely drying-in of ink between the images and drying-in of residual ink in the negative image.

[0052] Minimalization of the impression force is obtained, inter alia, by virtue of the remarkable use of magnets in the doctoring system, whereby the printing plate is drawn partially towards the doctoring system for printing plates with magnetic properties. The use of the double doctor blade also reduces the impression force, since a lower impression force is required relative to a traditional closed round or oval doctoring system in order to obtain the same quality of doctoring.

[0053] In order to reduce or even eliminate drying-in of the ink in or on the intermediate carrier, in particular printing plate, use is made of an integrated, though separate system which reduces or even removes undesired residues of ink from on and from out of the printing plate; the drying-in or drying-on of undesired ink is with certainty avoided to a greater extent. This is obtained by, for example, installing a second closed chamber doctoring system after the taking-up of the ink by means of the pad(s). This doctoring system, provided with the same ink or a cleaning agent, namely solvent, has several functions, including scraping off of any ink (wet or dry) which might yet still be present and is thus undesirable; general cleaning of the printing plate; re-wetting of the negative image and / or re-wetting of any ink residues between the images.

[0054] In an advantageous embodiment, this cleaning process can be replaced by a mechanical action, inter alia by brushing, or by controlled blowing out, and / or further optimized.

[0055] If an ink-compatible cleaning agent is used, it is necessary, moreover, that the excess cleaning agent which has not been taken up from the negative image is removed before ink is re-applied into this negative image or doctored. Otherwise, as a result of an excess of cleaning agent, especially solvent, insufficient ink - and thus colour pigment - would be applied into the negative image, resulting in a watery print. The removal of this excess of solvent can be realized via mechanical action, inter alia brushing, via blowing out, or even via forced, accelerated evaporation.

[0056] Care is taken to ensure that, in blowing-out or controlled evaporation, the zones between the images are made as residue-free as possible before this action. This can be done, for example, by installing an extra doctor blade between cleaning, in particular via a doctoring system with ink or solvent, and blowing-out / forced evaporation - for example with an air knife - or by installing this same extra doctor blade in advance of a new inking cycle.

[0057] A preferred embodiment also provides circulation systems for ink and / or solvent from and to the doctoring systems. This ensures that the viscosity of the ink is kept under control and that the cleaning agent, preferably solvent but also possibly ink, is kept clean. A continuous working of the inking system is hereby optimized.

[0058] The above-described cleaning of the printing plate is also, and in particular, of interest when the machine passes from production to stand-by, or even stops. After all, the presence of printing plate cleaning makes it possible to resume production without additional and time-consuming manual action by an operator owing to cleaning of the printing plate. Even if the inking system were to stop inking, then the drying-on and drying-in of residual ink would still constitute a problem with regard to quality of the printing when production is restarted.

[0059] The inking can be halted in a variety of ways. If inking is carried out digitally, the solution consists in a controlled stoppage of the inking. If, however, a closed chamber doctoring system is employed, the inking can be halted by a relative displacement of the doctoring chamber to a zone outside of the image zone. This can be done, for example, by displacing the doctoring chamber to the centre of the printing plate or by displacing the doctoring chamber away from the printing plate without departing from the scope provided in the claims.

[0060] An important prospect for the proposed technology is so-called digital pad printing.

Claims

1. Device for printing products (5) via an intermediate carrier of the pad type, consisting of a pad-based transfer system for media to be transferred by a pad (4) having an ink take-up and deposition axis, wherein it consists of an indexed linear pad printing system with rotation of a rotary disc about an axis (ℓ) of the device which is parallel to the ink take-up and deposition axis of the pad (4), characterized in that the rotary disc is in the form of a circular printing plate (3) that is coatable with ink by means of an ink pot (6), which is fixedly mounted, by rotation about the axis (ℓ), in particular wherein products (5) and pads (6) are synchronized in rotation about the same axis (ℓ) by a physical link, and in that the products (5) are movable along a circular path that is concentric with the circular printing plate (3), about the axis (f), wherein the pad (4) is movable to and from between two concentric paths, so that both the image can be taken-up from the circular printing plate (3) and is deposited on the product (5) with the same pad (4), and the product (5) is locatable on its concentric circular path and is removable therefrom again, within the cycle of one single rotation.

2. Device according to the preceding claim, characterized in that it comprises a plurality of single-color systems that are placed one after the other, for a multiple color system, wherein the products (5) are positioned correctly during the application of the different colors3. Device according to claims 1 or 2, characterized in that the image to be printed is absorbable selectively by the pad (4), in particular from an inked solid surface, notably indirect gravure.

4. Device according to one of the preceding claims comprising a doctor blade system, especially with a closed chamber, characterized in that the doctor blade system comprises at least one set of magnets which are provided in co-operation with said printing plate (3) having magnetic properties, in particular consisting of a magnetic material such as of the ferromagnetic type, in such a way that the printing plate (3) is pulled partly towards the doctor blade system and / or in that said doctor blade system comprises a double doctor blade (28) both of which are opposite to each other for scraping off the ink in pad printing, when inking an engraved printing plate (29) from the ink pot (6) wherein the bottom edge of the one doctor blade (28) is in contact with the printing plate (3), and a relative motion (21; 23) of the doctor blade (28) with respect to the printing plate (3) is generated, in a direction to ink the printing plate (3) on the one hand, and in the other direction to scrape the ink from the printing plate (3), on the other hand.

5. Device according to one of the preceding claims, characterized in that an integrated yet separate system is provided herein in such a way that undesired ink residues from the printing plate (3) are reduced so as to counter undesired ink drying, in or on the printing plate (3) as intermediate carrier, by incorporation of a second doctor blade with a closed chamber after take-up of the ink by means of each pad (4), and wherein it performs several functions, including scraping off any residual ink, either wet or dry; general cleaning of the printing plate (3); wetting again of negative image; and moistening again of any ink residues between the images.

6. Device according to claim 5, characterized in that it comprises - an additional doctor blade between cleaning -via the doctor blade system with ink or solvent- and blowing out or forced evaporating, by means of an air knife, in order to make the areas between the images residual free for this action when blowing out or controlled evaporating, - ink and solvent circulation systems to and from the doctoring systems, in order to keep the ink viscosity under control, wherein the cleaning agent is kept unaltered, for the sake of a continuous operation of the inking system, and / or - a printing plate cleaning system by virtue whereof the production is resumable without additional manual operation by a cleaning operator of the printing plate (3).

7. Method for printing products (5) via an intermediate carrier of the pad type according to the device provided in any one of the claims 1 to 6, wherein a printing medium such as ink, varnish, adhesive, conductive paste, thermoplastics, is transferred to the product (5) through said pad (4), characterized in that a circular printing plate (3) is inked by rotation about the axis (ℓ) by means of an ink pot (6) which is fixedly mounted, wherein in particular the products (5) and the pads (6) are synchronized in rotation about the same axis (ℓ) by a physical link, in particular wherein the vertical take-up motion by means of a vertical sliding system (8) of the pads (4) is performed by moving a reference point of the pads (4) via a cam system in a cam (9) ridge, wherein both the vertical motion - up- and-down - for the take-up of the image from the printing plate (3) and the vertical motion for the deposition of said image on the product (5) is performed during a rotation cycle about the axis (ℓ), wherein the products (5) are moved about the axis (ℓ) along a circular path that is concentric with the circular printing plate (3), wherein the pad (4) is moved back and forth between said two concentric paths in order to both take-up the image from the printing plate (3) and deposit the recorded image on the product (5) with the same pad (4), wherein in particular for the sake of the preceding back and forth motion (7), which is horizontal, a reference point of the pad (4) is moved through the cam system in the cam (9), further wherein the product (5) is placed on said concentric circular path and removed again within the cycle of one rotation.

8. Method according to claim 7, characterized in that when inking through a closed chamber doctor blade system, a set of magnets is operated in the doctor blade system under the action whereof the printing plate (3) with magnetic properties is pulled partly towards the doctor blade system, with reduction of a compressive force on the printing plate (3), and / or in that a double doctor blade (28) is operated with a reduction of compressive force on the printing plate (3), in that the cleaning process is replaced by or further optimized by means of a mechanical action, including through brushing, or via controlled blowing out; and / or in that the removal of the excess solvent through mechanical action, in particular brushing, is performed by blowing out or even by forced accelerated evaporation, wherein when blowing out or controlled evaporating, the areas between the images are made residual free for this operation.