WO2009103396A1

WO2009103396A1 - Method for inking a printing forme in a processing machine

Info

Publication number: WO2009103396A1
Application number: PCT/EP2009/000454
Authority: WO
Inventors: Peter Hummel; Robert Ortner; Jürgen Schölzig
Original assignee: Manroland Ag
Priority date: 2008-02-19
Filing date: 2009-01-24
Publication date: 2009-08-27
Also published as: DE102008009890A1

Abstract

The invention relates to a method for inking a printing forme in a processing machine for stocks. The aim of the invention is to devise a method that especially allows ink to be metered in a stable manner in a universally usable inking unit while noticeably reducing the ghosting tendency. Said aim is achieved in a processing machine for stocks, comprising an inking unit, an optional dampening unit, and a plate/form cylinder that has the printing forme. The inking unit encompasses an ink metering and ink delivering device, at least one roller train, and inking rollers for inking the printing forme. The flow of ink is fed to a distribution roller (8) where the flow of ink is additionally split on a third partial roller train (21) that is mounted downstream of the second partial roller train (13) in the direction of rotation of the plate/form cylinder (1), and the third partial flow of ink of the third partial roller train (21) is fed to the second partial flow of ink of the second partial roller train (13) upstream of the inking rollers (3, 4, 5) of said second partial roller train (13).

Description

Process for coloring a printing form in a processing machine

The invention relates to a method for coloring a printing form in a processing machine for substrates according to the preamble of the independent claim.

From EP 0 280 957 A2 an inking unit for a printing unit in an offset printing machine is known. The printing unit comprises a plate cylinder having a printing plate, wherein a dampening unit can be assigned to the plate cylinder. The inking unit comprises a distributor roller arranged in the roller train for the ink feed and two sub-roller trains arranged in parallel downstream of this distributor roller. The ink stream is divided from the distributor roller by means of two partial roller trains in two partial color streams and the two partial color streams are fed to a front in the direction of rotation of the plate / forme inking roller for coloring the printing plate.

A method and a device for color guidance are known from DE 10248 517 A1 or from EP 0 741 024 A2. Thereafter, an inking roller train comprises a distributor roller and two sub-roller trains arranged in parallel downstream of said distributor roller and each having at least one inking roller in contact with a printing plate. The partial rolling trains can be separated at at least one nip so that temporarily the ink stream can be supplied to at least one of the inking rollers via the first or the second partial drawing train. Such color flow separations can prevent a change in the ink layer thickness profile in ongoing inking at printing interruptions. After elimination of the print interruption, the rollers are re-set together at the start of printing, so that the original color flow is restored. The invention is based on the object to provide a method of the type mentioned above, which allows in particular a stable color guide in a universally applicable inking and noticeably reduces the tendency for stenciling.

The problem is solved by the training features of claim 1. Further developments will become apparent from the dependent claims.

As is known, the stenciling is an error phenomenon during printing, in which a structure of the printing form - offset in the printing direction - one or more times additionally images.

A first advantage of the solution according to the invention therefore lies in the fact that, especially in the case of difficult printing plates and / or special printing inks, such as metallic inks or inks that absorb excessively dampening solution, these irregularities when coloring a printing forme are avoided or at least noticeably reduced.

A second advantage is due to the fact that, starting from a distributor roller arranged in the roller train of an inking unit, the color flow in the printing operation or the planned ink flow is already influenced in a targeted manner even before the start of printing (in the case of machine standstill). For this purpose, in the inking unit, the amount of ink (color flow) supplied in the direction of the printing form can be supplied in variable ink flow proportions to the respective inking rollers. Thus, color flow components can be realized, which result in different working methods of the inking unit, a different load distribution of the ink flow in the inking unit. The inking unit is universally applicable for a variety of Drucksujets, responsive and the existing inking rollers remain preferred - despite different switching positions - always in the respective color flow.

Starting from the distributor roller, the ink flow to a front-heavy designed inking unit, ie at least in the direction of rotation of the plate / forme cylinder first and preferably second, optionally third inking roller are supplied with a relatively high ink flow rate and the remaining reduced ink flow rate is the other, for example, third and fourth and optionally further, inking rollers supplied.

Alternatively, from the distributor roller, the ink flow to a medium-duty inking unit, i. to the in the direction of rotation of the plate / forme cylinder at least second and preferably third inking roller are supplied with a relatively high ink flow rate and the remaining reduced ink flow rate is the other, for example, first and fourth and optionally further, inking rollers supplied.

Alternatively, from the distributor roller, the ink flow may be directed to a rear-loaded inking unit, i. to the in the direction of rotation of the plate / forme cylinder at least third and preferably fourth inking roller are supplied with a relatively high ink flow rate and the remaining ink flow rate is the other, for example, first and second and optionally further, inking rollers supplied.

It is also advantageous that, in the event of a possible occurrence of stenciling phenomena during printing, the inking unit can be selectively operated by switching operations of the ink transport rollers downstream of a distributor roller in a first and second partial roller train, if necessary also inking rollers, the inking unit can be operated in universal working methods. Thus, possible stencilling phenomena are avoidable or at least significantly reducible with a simultaneously stabilized color guide. In this case, the change of the ink flow can be carried out from the distributor roller according to the respective operation in the machine downtime and during the printing operation.

The invention will be explained in more detail using an exemplary embodiment. Here are shown schematically: 1 is an inking unit of an offset printing machine,

Fig. 2-7, the inking unit in each case a further training.

According to Figure 1, an inking unit for an offset printing machine is shown, which u. a. a Farbdosier- / feeding device 10 includes. This Farbdosier- / feeder 10 may preferably be formed by a paint box with metering device and with ink fountain roller and a Farbheberwalze or a film inking roller. The ink fountain roller or the film inking roller is preferably in operative connection with a fourth inking roller 9. At least one compactor 11 having a plurality of ink-transfer rollers, which form a first ink stream, is arranged downstream of the fourth ink-jet roller 9 in the direction of ink flow. This first color flow is transferred to a, one of the ink transfer rollers downstream distributor roller 8, which distributor roller 8 may preferably be formed as a third inking roller 8.

Viewed in the direction of color flow, the further compactor splits at the distributor roller 8 and thus the color flow over two subordinate, designed as branch rollers ink transfer rollers 15, 16 into a first and a second partial roller train 12, 13 and thus the color flow divided into two partial color streams. Each of the sub-roller trains 12, 13 may include a plurality of ink-transfer rollers as needed. The two partial ink streams are fed to a front in the direction of rotation of the plate / forme cylinder 1 inking roller, here a second inking roller 3.

In the present example, the first partial roller train 12 in the direction of rotation of a plate / forme cylinder 1 is formed by the ink transport roller 15 designed as the first branch roller and a first inking roller 6 arranged downstream of this. The first partial ink flow is supplied to the first inking roller 6 and the subsequent front (first two) inking rollers 2, 3 of the inking unit as seen in the direction of rotation of the plate / forme cylinder 1 via the ink-transporting roller 15. Furthermore, in the direction of rotation of the plate / forme cylinder 1 second partial roller train 13 is formed by the executed as a second branch roller ink transfer roller 16 and a downstream of this ink transport roller 17. The ink transport roller 17 is in the form of a bridge roller with the front, second inking roller 3 and a downstream in the direction of rotation of the plate / forme cylinder 1, third inking roller 4 in contact. The third inking roller 4 is downstream of a fourth inking roller 5 in the direction of rotation of the plate / forme cylinder 1, wherein both inking rollers 4, 5 are bridged by a second inking roller 7. Via the ink transfer roller 16, the second partial ink flow is thus supplied to the two inking rollers 3, 4 via the ink transfer roller 17. From the third inking roller 4 7 ink on the fourth inking roller 5 is fed via the second ink fountain roller.

From the inking rollers 2 to 5, the color is supplied to the plate / forme cylinder 1. The plate / form cylinder 1 carries a fixable on the lateral surface printing plate, for example as a printing plate or sleeve. Alternatively, on the lateral surface of the plate / forme cylinder 1 a printing form can be generated, fixed and preferably erasable. All Farbreiberwalzen 6 to 9 are rotationally and / or axially iridescent drivable. All inking rollers 2 to 5 are driven by friction and are formed on / off adjustable. If necessary, the inking rollers 2 to 5 may be formed axially iridescent, the traversing movement is also stopped. The first, third and fourth inking rollers 2, 4 and 5, if necessary, individually, in groups or total smoothing rollers 23 are assigned directly.

For wet offset printing, a dampening unit 14 may be arranged upstream of the inking unit 14 in the direction of rotation of the plate / forme cylinder 1.

In addition to the two partial roller trains 12, 13 described above, the additional roller train splits at the distributor roller 8 into a third partial roller train 21 in the direction of the color flow. Thus, the ink flow is adjacent to the two downstream color transport rollers 15, 16 of the first roller train. th and second Teilwalzenzugs 12, 13 in a third Teilwalzenzug 21 and thus the color flow in addition divided into a third partial color flow. Each of the sub-roller trains 12, 13, 21 may include a plurality of ink-transfer rollers as needed. The two partial ink streams 12, 13 are fed to a front in the direction of rotation of the plate / forme cylinder 1 inking roller, here a second inking roller 3.

In the present example, the third partial roller train 21 is formed by at least one ink transport roller 20 designed as a third branch roller. This third sub-roller train 21 may also comprise a plurality of ink-transfer rollers. The third Teilwalzenzug 21 and thus the third partial ink flow is always the second Teilwalzenzug 13 before its inking rollers 3, 4, 5, wherein the third partial ink stream and individual or groups of inking rollers 3, 4, 5 can be supplied.

Starting from the basic embodiment shown in FIG. 1, depending on the print job and / or the rheological conditions on the distributor roller 8, the ink flow is third adjacent to the second partial roller train 13 in addition to the first and second partial color streams Partial train 21 divided. In this case, the third partial ink flow of the third partial roller train 21 is supplied to the second partial ink flow of the second partial roller train 13 before its inking rollers 3, 4, 5.

In one embodiment, the third partial roller train 21 can be temporarily interrupted at a separating point 22. The color flow thus takes place via the first and second partial color streams.

In a further embodiment, the third sub-roller train 21 is temporarily interrupted at a separation point 22 downstream of the distributor roller 8, and a color transfer roller 20 of the third sub-roller train 21 is integrated into the second sub-roller train 13 in front of the inking rollers 3, 4, 5. In a further development, the ink transfer roller 20 is temporarily with a Ink application rollers 3, 4 upstream ink transfer roller 17 and the inking rollers 4, 5 upstream inking roller 7 brought into contact.

In a further embodiment, the second sub-roller train 13 is temporarily interrupted at a separation point 19, the first and the third sub-roller train (12, 21) are in contact with the distributor roller 8 and the third partial ink flow of the third sub-roller train 21 is after the separation point 19 the remaining second Teilwalzenzug 13 supplied. In a further development, the second partial roller train 13 is temporarily interrupted at a separation point 19 downstream of the distributor roller 8, and a ink transfer roller 16 of the second partial roller train 13 is provided with an ink roller 6 arranged upstream of the first and second inking rollers 2, 3 and the second and third inking rollers 3, 4 upstream color transport roller 17 brought into contact.

In a further embodiment according to FIG. 4, temporarily the second partial roller train 13 and thus the second partial color flow can be interrupted and integrated into the first partial roller train 12. For this purpose, a color-conveying roller, here the ink-transporting roller 16, is brought into contact with a color-conveying roller of the first part-roller train 12. In the present example, the ink transfer roller 16 is temporarily brought into contact with the first inking roller 6 and remains in contact with the distributor roller 8.

Furthermore, a further ink transport roller 17 of the second partial roller train 13 can be temporarily integrated into the third partial roller train 21. The partial color streams are thus fed exclusively via the first partial roller train 12 (first partial color flow) and the third partial roller train 21 (third partial roller train) to the inking rollers 2, 3 (first partial color flow) and 4, 5 (third partial color flow). Preferably, the color transfer roller 17 acting as a bridge roller is separated from the second inking roller 3 at a separation point 18 and brought into contact with the third ink transport roller 21 of the third partial roller train 21 and remains in contact with the third inking roller 4. In a further embodiment according to FIG. 5, the second and third partial roller train 13, 21 can be temporarily separated from the distributor roller 8. For this purpose, the ink transfer roller 20 are preferably separated at a separation point 22 and the ink transfer roller 16 at a separation point 19 in each case from the distributor roller 8. In this case, starting from the distributor roller 8 (the first partial roller train 12 remains in contact with the distributor roller 8, the first partial ink flow of the first partial roller train 12 of all downstream ink transfer rollers 16, 17, 20, the first and second ink distributor rollers (6, 7) and the first to fourth inking rollers (2 to 5) supplied.

In a further embodiment according to FIG. 6, the second partial roller train 13 can be temporarily interrupted at a separation point 19 and integrated into the first partial roller train 12. The third partial roller train 21 is temporarily integrated into the second partial roller train 13. For this purpose, the ink transfer roller 16 adjacent to the distributor roller 8 is temporarily brought into contact with the first inking roller 6 of the first partial roller train 12, the ink transport roller 16 remaining in contact with the distributor roller 8. Further, the ink roller 20 of the third partial roller train 21 adjacent to the distributor roller 8 is temporarily brought into contact with the remaining partial roller train 13, especially the ink transfer roller 17 of the second partial roller train 13, with the ink transfer roller 20 remaining in contact with the distributor roller 8.

In a further embodiment of FIG. 7, the second Teilwalzenzug 13 is temporarily interrupted at a separation point 19 and the distributor roller 8 adjacent Farbtransportwalze 16 of the second Teilwalzenzuges 13 is temporarily integrated into the first Teilwalzenzug 12, wherein the ink transfer roller 16 with the distributor roller 8 in contact remains. The third Teilwalzenzug 21 is interrupted at a separation point 22 between the distributor roller 8 and the ink transfer roller 20 and the ink transport roller 20 of the third Teilwalzenzuges 21 is temporarily brought out of contact with the distributor roller 8 and in the remaining second Teilwalzenzug 13, preferably with the ink transfer roller 17 and second inking roller 7 brought into contact, is integrated. In the design of the inking unit according to FIG. 1, 2 and 3 color flow components of a total of approximately 60% result at the first and second inking rollers 2 and 3. The third inking roller 4 has - based on the total ink flow shares of the two inking rollers 2 and 3 - by approximately 50% reduced ink flow rate and the fourth inking roller 5 has the lowest ink flow rate.

In the design of the inking unit according to FIG. 2 arise at the first and second inking roller 2 and 3 Farbflussanteile totaling approximately 60%. The third inking roller 4 has a - based on the total ink flow shares of the two inking rollers 2 and 3 - by approximately 60% reduced ink flow content. Although the fourth inking roller 5 has the least, but based on the embodiment of FIG. 1, an approximately twice as high color flow content.

In the design of the inking unit according to FIG. 3, the first and second inking rollers 2 and 3 result in color flow components of approximately 65% in total. The third inking roller 4 has a - based on the total ink flow shares of the two inking rollers 2 and 3 - by approximately 60% reduced ink flow content. Although the fourth inking roller 5 has the lowest, based on the embodiment of FIG. 1, approximately the same color flow content.

After completion of the print job, alternatively in the printing operation, the color flow can be switched to the basic version of FIG. LIST OF REFERENCE NUMBERS

1 plate / form cylinder

2 first inking roller 3 second inking roller

4 third inking roller

5 fourth inking roller

6 first inking roller

7 second inking roller 8 distributor roller (third inking roller)

9 fourth inking roller

10 paint dosing / feeding

11 compactor (first color flow)

12 first partial roller train (first partial color flow) 13 second partial roller train (second partial color flow)

14 dampening unit

15 ink transfer roller (first branch roller)

16 ink transfer roller (second branch roller)

17 ink transfer roller 18 separation point (ink transfer roller 17 / inking roller 3)

19 separation point (second partial color flow)

20 ink transfer roller (third branch roller)

21 third partial roller train (third partial color flow)

22 separation point (third partial color flow) 23 smoothing roller

Claims

claims

1. A method for coloring a printing form in a processing machine for substrates, with an inking unit and optionally a dampening unit and a printing plate having plate / forme cylinder, wherein the

Inking unit comprises a Farbdosier- and Farbzuführeinrichtung, at least one compactor and inking rollers for inking the printing form and the ink stream is supplied to a distributor roller, is split at the distributor roller by means of two sub-roller trains in two sub-color streams and the two sub-color streams to a front in the direction of rotation of the plate / forme cylinder

Ink roller are supplied, characterized in that the ink flow at the distributor roller (8) in addition to a in the direction of rotation of the plate / forme cylinder (1) the second part roller train (13) downstream third Teilwalzenzug (21) is divided and the third partial color flow of third Teilwalzenzuges (21) the second partial ink flow of the second part roller train (13) before its inking rollers (3, 4, 5) is supplied.

2. The method according to claim 1, characterized in that the third sub-roller train (21) is temporarily interrupted at a separation point (22).

3. The method according to claim 1, characterized in that the third sub-roller train (21) is temporarily interrupted at one of the distributor roller (8) downstream separation point (22) and a Farbtransportwalze (20) of the third Teilwalzenzuges (21) in the second Teilwalzenzug (13 ) is integrated in front of the inking rollers (3, 4, 5).

4. The method according to claim 3, characterized in that the ink transfer roller (20) temporarily with a the inking rollers (3, 4) upstream ink transport roller (17) and a Farbauftragwal- zen (4, 5) upstream inking roller (7) brought into contact becomes.

5. The method according to claim 1, characterized in that the second partial roller train (13) is temporarily interrupted at a separation point (19), the first and the third partial roller train (12; 21) are in contact with the distributor roller (8) and the third partial ink flow of the third partial roller train (21) is fed to the second partial roller train (13) after the separation point (19).

6. The method according to claim 1, characterized in that the second Teilwalzenzug (13) is temporarily interrupted at one of the distributor roller (8) downstream separation point (19) and a Farbtransportwalze (16) of the second Teilwalzenzuges (13) with a first and second Ink application rollers (2, 3) upstream ink roller (6) and a second and third inking rollers (3, 4) upstream color transport roller (17) is brought into contact.

7. The method according to claim 1, characterized in that the second Teilwalzenzug (13) is temporarily interrupted at a separation point (18) and one with the distributor roller (8) in contact Farbtransportwalze (16) of the second Teilwalzenzuges (13) in the first Partial roller train (12) is integrated and the inking rollers (3, 4) upstream ink transport roller (17) of the second Teilwalzenzuges (13) is temporarily integrated into the third Teilwalzenzug (21), wherein the ink transfer roller (17) with the inking roller (4) remains in contact.

8. The method according to claim 1, characterized in that the second Teilwalzenzug (13) is temporarily interrupted at a separation point (19) and the third Teilwalzenzug (21) at a separation point (22) is interrupted, the first Teilwalzenzug (12) with the Distributor roller (8) remains in contact and the first partial ink flow of the first part roller train (12) all subordinate ink transfer rollers (16, 17, 20), the Farbrei- berwalzen (6, 7) and the inking rollers (2 to 5) is supplied.

9. The method according to claim 1, characterized in that the second part-roller train (13) is interrupted temporarily at a separation point (19) and the distributor roller (8) adjacent to the ink-transporting roller

(16) of the second sub-roller train (13) is temporarily integrated into the first sub-roller train (12), the ink-transporting roller (16) remaining in contact with the distributor roller (8), and the third sub-roller train (21) being connected to the distributor roller (8). remaining in contact with the remaining second sub-roller train (13).

10. The method according to claim 1, characterized in that the second part-roller train (13) is temporarily interrupted at a separation point (19) and the distributor roller (8) adjacent to the ink-transporting roller

(16) of the second sub-roller train (13) is temporarily integrated into the first sub-roller train (12), the ink-transporting roller (16) remaining in contact with the distributor roller (8), and in that the third sub-roller train (21) is located at a separation point (22). between distributor roller (8) and ink transfer roller (20) is interrupted and the ink transport roller (20) of the third partial roller train (21) is brought out of contact with the distributor roller (8) and in the remaining NEN second Teilwalzenzug (13) is integrated.