DE2126091A1 - Printing process and apparatus for its implementation - Google Patents

Description

Applicant: Stuttgart, 10th UrI 1971

Wilfried Philipp P 2297 XAs

7254 Münchingen-Kallenberg
Daimlerstrasse 27/1

Printing process and apparatus for its implementation Addendum to patent ... (Λζ. Ρ 19 39 4-37.7)

The invention relates to a printing method in which an r.iit Color-absorbing depressions provided cliché and the color is doctored so far that the color only sits in the grooves, and in which a pressure pad is pressed onto the cliché and the one from the pressure pad The color picked up from the cliché is transferred from the printing pad to the item to be printed, with after Patent ... (Az. P 19 39 4-37 7) a pressure pad with a the paint used in such a degree repellent surface is that it just takes on the color when it is pressed onto the cliché, but when it is pressed onto it the printing material emits the liquid or pasty ink practically completely, as well as a device for implementation this procedure.

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In the case of the Stamrian registration process, the so-called pad printing process, in which a pressure pad made of gelatin was used, thereby significantly improved that a pressure pad with an ink-repellent surface was used. Are there the color-repellent properties of the surface are selected so that that the pressure pad still takes on color when it is pressed against the cliché, but this color takes on the next Pressing on objects to be printed is practically completely released. This is practically about a stamping process in which instead of an ink pad a corresponding cliché is used. The advantages achieved are that a very good covering Pressure is achieved with the finest contour sharpness at the same time. The ink application density is comparable to that of screen printing; the sharpness of the contours is the gravure printing comparable. However, in the process according to the parent patent, the performance and thus the output are important limited because of a series of discrete procedural steps takes place one after the other.

The object of the present invention is to provide an improved method and an apparatus for carrying out this of the process that also has the advantages of the process according to the parent patent and thereby enabling a greater production and working speed.

The object is achieved according to the invention in that a transfer cylinder is used as the pressure pad and both is unrolled on the cliché as well as the item to be printed. The particular advantage of the inventive η

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The method is that both faster work can be carried out and larger areas in one operation can be printed. While the to be printed

When using a transfer cylinder, the entire area of the cylinder can be used for printing and this area can easily reach a hundred times the area of the printing pad or the stamp. In this way, a significantly increased output can be achieved in the same time. In addition however, also added that the transfer cylinder is already printing items, but have other ^r üeile the transfer cylinder rolled on the cliché v / ground. As a result, the individual work steps overlap laterally, which also enables increased output. The print quality is just as good as with pad printing; So opaque and at the same time razor-sharp prints are achieved. In the case of the invention, the transfer cylinder is thus experienced on the cliché and then, if necessary, also

partly at the same time, unrolled on the item to be printed.

In the method described, the cliché can be designed as a flat, planar cliché. At a preferred embodiment of the invention, however the cliché produced as a forme cylinder. The particular advantage is that it is completely continuous operation is possible. It is possible without difficulty to apply paint continuously to the rotatable

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Make forme cylinder and squeegee continuously with a doctor blade. Although a wide variety of inking units can be used to apply the ink, in a preferred embodiment of the invention for applying the ink, the forme cylinder is immersed in a paint basin in a manner known per se and the forme cylinder is wiped off by rotating it around its axis on a stationary squeegee. This kind of application of color and Abrakelns is particularly suitable for applying thick-W liquid, soft or pastö'ser color ·

The movement of the transfer cylinder and the forn cylinder can be made differently. With a preferred Embodiment of the invention for the transfer cylinder together with the forme cylinder, a back and forth movement when unrolling on the item to be printed the end. A work step is carried out when moving in one direction.

In a particularly preferred embodiment of the invention, on the other hand, the item to be printed is guided tangentially past the transfer cylinder, the vroboiler forme and the transfer cylinder are driven to rotate. By this inventive method ^ ³ ^ ^Θ ^ ^η rotary printing process created, 'with which a working speed comparable to rotogravure printing with at the same time color density comparable to screen printing and a razor-sharp print image can be achieved. * Juiü passing the goods to be printed, these can be conveyed past on a conveyor belt or a conveyor table. This is the conveyor table or the conveyor belt

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go formed that the contact pressure with which the goods to be printed ran against the transfer cylinder must be picked up by the conveyor belt or the conveyor table will. If a tape is printed, for example paper or fabric or the like. In a preferred one Embodiment of the invention is a ger print roller provided and it is the material to be printed between the transfer cylinder and the impression roller carried out. Although flat, band-shaped goods can also be printed in this way, such as in particular foils, cardboard, paper, cloth and the like, which have a flat surface, is advantageous It is also possible to print on relatively uneven material, such as ribbed or otherwise profiled material. The Shore hardness and the ink-repellent properties of the transfer cylinder can be used adapted to each printing problem. The particular advantage of the method according to the invention lies in this in that, due to the ink-repelling properties of the transfer cylinder, a razor-sharp print image is achievable.

In preferred embodiments of the invention, a Transfer cylinder made of silicone rubber with preferably high elasticity is used.

The method according to the invention is particularly advantageous when using screen printing inks which can be based on plastic or synthetic resin. It is also possible and in preferred embodiments intended to use stoving colors. Advantage-

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haft int with this procedure also that it is due to The relatively high working speed can also be done with colors that are relatively quick dry.

The present invention further relates to an apparatus for performing the method with the color in wells receiving plate, an inking unit for applying ink from an ink reservoir to the w cliché and a doctor blade for doctoring the Klincliees. Such a known device is gravure printing which can be carried out as sheet-fed printing or as rotary printing. It is also known to transfer the color from the cliché to the item to be printed by means of a pressure pad, which is carried out by means of tarapon printing machines. Based on such a known I-.Iasch.ine the device according to the invention is characterized in that a rotatably mounted transfer cylinder is provided for transferring the color from the cliché to the item to be printed, which cylinder is mounted both on the cliché and on the Gxit to be printed is unrollable. This device advantageously allows the method according to the invention to be carried out; it can be used to produce prints with excellent coverage and sharp contours.

In a preferred embodiment of the invention the cliché designed as a gravure forme cylinder, too which the transfer cylinder is mounted axially parallel with a center distance that is at most as large as the Eadiene number of the two cylinders. The two cylinders

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so lie against each other under a certain bias at. It is not absolutely necessary that the two cylinders have exactly the same diameter on v / one, since In addition, it is not absolutely necessary that the cylinders have mutually corresponding positions come into contact, as the color of the transfer cylinder is practically completely removed from the object to be printed will. In preferred embodiments, however, the two cylinders have the same diameter and are positively coupled to each other · thereby This also means that there are no faults or errors in the printing process there may be slight residues of fiber on the transfer cylinder get stuck because these ink residues come into contact again with the same ink spot on the forme cylinder.

The inking unit can be designed differently, for example as V / al ζ en farbwerk ο with a preferred However, the form cylinder is an embodiment of the invention Arranged immersed in the ink pan and there is a fixed squeegee on its surface, as if on itself known. Coloring is done in the same way made with conventional gravure cylinders. The left 1 is on the paint tray in a manner known per se appropriate. Ink tray and squeegee form a unit.

In preferred embodiments of the invention that is The good to be printed is fixed and it is the Unit consisting of "transfer cylinder, forme cylinder and inking unit attached to a reciprocating slide. The The printing process always takes place with one movement,

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whereas the other movement removes the item to be printed.

In preferred embodiments, however, there is a conveyor table Provided under the transfer cylinder, which conveys the goods to be printed past. So it's the one Transfer cylinder and the forme cylinder with inking unit are fixed and the item to be printed is ^ guided through the machine and printed.

For printing inherently flexible, ribbon-shaped goods. is in one embodiment of the invention an impression cylinder intended for pressing the item to be printed onto the transfer cylinder.

The advantages of the last-mentioned embodiments of the invention are that this device combines the work speed of a rotogravure printing with the technical printing advantages of screen printing, since with a high output a more congruent and sharply contoured printing is achieved. By appropriate W-speaking v / o St. hardness and farbabwe is properties of the transfer roller, the variety of materials can be printed and it is also not necessary, 'that is completely flat surface to be printed, since the elastic transfer cylinder to the article surface adapts as is known from pad printing. Given the high elasticity of the transfer roller, even very uneven object surfaces can be printed perfectly and with sharp contours.

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Further details and embodiments of the invention emerge from the following description of FIG Embodiments shown in the drawing. They show in a greatly simplified, schematic representation :

Fig. 1 shows a device according to the invention with a fixed flat cliché and back and forth movable transfer cylinder,

Fig. 2 shows another embodiment of the invention Form cylinder, transfer cylinder and print material moved past, and

FIG. 3 shows an arrangement similar to FIG. 2 with an impression cylinder.

A flat cliché 2 is on a flatbed table 1 attached. On the machine table 1 a plate 4 is movable via rollers 3, on which the objects to be printed 5 are attached. The upper surface of the objects 5 lies approximately in the same plane as the surface of the cliché 2. Above the machine table 1, a rail track 6 is provided in which a cylinder carriage 7 is guided back and forth by means of rollers 8. The rail track 6 has an upper rail 16 and. a lower rail 17, between which there are two transitions by movable flaps 18 and 19. The movable ones Flaps are pivotably mounted in the area between the upper rail and the lower rail 17. It lies the movable flap 18 under the force of a spring, not shown, in the one drawn in solid lines in the figure

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Location, whereas the movable flap 19 on the lower one The track of the lower rail 17 rests. A transfer cylinder 9 is rotatably mounted on the cylinder carriage 7. A piston rod 10 is articulated on the cylinder carriage 7 attached, at the other end of a piston, not shown, is attached, which in a lifting cylinder 11 back and is moveable. In addition, a paint application carriage 12 can be moved in the rail track 6 by means of rollers 20. Of the Paint application carriage 12 is by means of a rod 13 articulated to it and to the cylinder carriage 7 with the Cylinder carriage 7 coupled. The paint application carriage 12 is provided with a paint applicator, for example a brush 14 and also carries a squeegee 15 · Moves the piston rod 12 by correspondingly acting on the lifting cylinder 11 in the direction of arrow 21, wherein First the cylinder carriage 7 is close to the lifting cylinder 11 is located, the paintbrush 14- wipes over the surface of the cliché 2 and colors this one. The surface of the cliché 2 is then wiped off by the squeegee 15 «The end of the paint application process is shown in FIG. The brush 14 then arrives in a paint tray 22, where it again Absorbs color. However, the color level is so low that the doctor blade 15 is not immersed in the color. Afterward the transfer cylinder 9 runs over the surface of the cliché 2 and takes color from the on its surface Cliché. When the paint application carriage 12 is moved through the area of the movable flap 19, the latter is raised and the paint application carriage continues to run. In the same way, the flap 19 is also supported by the cylinder carriage 7 raised. If the cylinder carriage 7 has passed the flap 19, the lifting cylinder 11 is reversed and the two carriages

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"move in the opposite direction to the direction Arrow 21. The carriage 7 runs out of the lower rail 17 via the flap 19 into the upper rail 16. The paint application carriage 12 also runs on the way back up into the upper rail 16. As soon as the cylinder carriage 7 reaches the flap 18, it reaches at the same time the paint application carriage 12 has a previously locked and now unlocked flap 18 '. The weight of the car is pressing the flap 18 or 18 'downwards, so that the two carriages get into the lower rail 17 again. Donach snap the flaps 18 back into the position shown under the action of springs, not shown. In the following Movement in the direction of arrow 21 we the transfer roller 9 guided over the objects to be printed 5, the color from the transfer roller 9 on the Objects is transferred with sharp contours.

In the Ausführungsforra shown in Fig. 2 is held of the cliché 2 a forme cylinder 32 with a corresponding Engraving or etching provided rotatably mounted in a machine frame, not shown. The forme cylinder 32 dips into an ink pan 42 on which a squeegee 4-5 is attached, the excess ink from the forme cylinder 32 circulating in the direction of arrow 51 squeegees. In the machine frame, not shown, is also axially parallel to the forme cylinder 32, a transfer cylinder 39 rotatably mounted, which bears against the forme cylinder 32 under prestress. Under the transfer cylinder 39 is the Material to be printed, for example a plate 35, by a conveying device (not shown) in the direction of arrow 52

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passed under the transfer cylinder 39 and pressed against it. It goes without saying that the Surface speeds of the forme cylinder 32 and of the "transfer cylinder 39 are the same and that, on the other hand, the peripheral speed of the transfer cylinder 39 is equal to the speed of displacement of the plate 35 in the direction of arrow 52. It is understood that instead of the plate 35 also individual parts on a correspondingly moved machine table or conveyor belt the transfer roller 39 can be passed and printed.

In the embodiment shown in Fig. 3 is as Print material a paper, film or fabric web 31 is provided, which is guided along the transfer cylinder 39. Since the web 31 is inherently soft, so not through Longitudinal tensioning with great pressure on the transfer cylinder can be applied, is provided axially parallel to the transfer cylinder 39 sin impression cylinder 33. The light one Distance between the impression cylinder 33 and the transfer cylinder 39 is generally less than the thickness of the web 31. The clear gap may or may not be zero the impression cylinder also rest against the transfer cylinder 39 under prestress. The three cylinders, forme cylinders 32, transfer cylinder 39 and impression cylinder are rotatably mounted in a common machine frame. Preferably, all three cylinders are interlocked with one another Coupled via toothed wheels (not shown), possibly also by means of toothed belts or chain drives, that their peripheral speeds are equal to one another.

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It goes without saying that the invention is not restricted to the exemplary embodiments shown, but that deviations therefrom are possible without departing from the barges of the invention. In particular, it is possible to use the method according to the invention in all gravure printing machines, that is to say both in sheet-fed printing machines and in web-fed rotary machines. The difference from the usual printing. machines consists in the fact that the object to be printed does not come into direct contact with the cliché or the forme cylinder but that the transfer takes place by means of the transfer cylinder. Since the transfer cylinder has a smooth surface and can also be designed to be elastic, it is not necessary to work with such high compressive forces and with felt layers and the like for gravure printing, since the medium to be printed does not have to be pressed into the depressions. './ is used for printing Βλη ^! . ■ - ■> r is used, it is not necessary int that it particularly absorbent and strong isb and before printing angefeuchtol; • ■ / must be grounded. The invention is thus a combination of gravure printing and planographic printing, which advantageously combines the advantages of the two ancestors.

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Claims (16)

- 14- claims Printing process in which a! Color-absorbing Depressed cliché is dyed and the paint is wiped off so far that the paint only remains sits in the grooves, and in which a pressure pad is pressed onto the cliché and that of the pressure pad the color picked up from the cliché is transferred from the printing pad to the item to be printed, 'whereby according to patent ... (Az. P 19 39 4-37-7)' 'in pressure pad with one that repels the color in such a Liaß Surface is used, that although it just barely retains the color when it is pressed onto the cliché annually, but the liquid or pasty color practically completely when pressed onto the printed matter dispenses, characterized in that a transfer cylinder (9 or 39) is used as the pressure pad and is unrolled both on the cliché (2) and on the object to be printed (5). 2. The method according to claim 1, characterized in that that the cliché is made as a forme cylinder (32) will. 3. The method according to claim 2, characterized in that that to apply the color of the forme cylinder (32) in a known V / eise in a paint basin (4-2) is immersed and the forme cylinder (32) by rotating about its axis on a stationary doctor blade is being doctored. 209850/0973 4. The method according to any one of claims 1 to 3 »thereby Marked that the transfer cylinder together with the forme cylinder when unrolling executes a back and forth movement of the item to be printed. 5 · ancestors according to any one of claims 1 to 3, characterized characterized in that the goods to be printed are guided past the transfer cylinder tangentially and the forme and transfer cylinders are driven to rotate. 6. The method according to claim 5i, characterized in that that the item to be printed (31) between the transfer cylinder (39) and an impression cylinder (33) is passed through. 7. The method according to any one of the preceding claims, characterized in that a transfer cylinder (9 bzv /. 39) made of silicone rubber, preferably of high elasticity, is used. 8. The method according to any one of the preceding claims, characterized by the use of screen printing inks. 9. The method according to any one of claims 1 to 7, characterized by the use of stoving colors. 209850/0973 10. Device for carrying out the process according to one of the preceding claims, with a cliché receiving the color in depressions, a Inking unit for applying color to the cliché and a squeegee for doctoring the cliché, thereby characterized in that for transferring the color from the cliché (2 or 32) to the item to be printed rotatably mounted transfer cylinder (9 or 39) is provided is that on both the cliché and "can be unrolled on the item to be printed. 11. The device according to claim 10, characterized in that the cliché is designed as a gravure forme cylinder (32) is, to which the transfer cylinder (39) is mounted axially parallel with a center distance that is at most as large as the sum of the radii of the two Cylinder. 12. The device according to claim 11, characterized in that the two cylinders form-fit with one another are coupled. · 13 · Device according to claim 11 or 12, characterized in that that the forme cylinder (32) is arranged immersed in the ink pan (4-2) and on its surface a fixed squeegee (4-5) is applied, as is. known. 14 ·. Device according to claim 13, characterized in that that the squeegee (4-5) is attached to the paint tray (4-2) is, as is known per se. 209850/0973 15 device according to one of claims 11 to 14, characterized in that the item to be printed is fixed and the unit consisting of transfer cylinder, forme cylinder and inking unit attached to a reciprocating slide is β 16. Device according to one of claims 11 to, characterized in that a conveyor inch below the transfer cylinder (39) is provided, which conveys the item to be printed past. 17 · Device according to one of Claims 11 to, characterized in that an impression cylinder (33) is provided for pressing the item (31) to be printed onto the transfer cylinder (39). 2 0 9 8 5 0/0973