DE102008002042A1 - Imaging layers i.e. metallization layers, transferring device for use in sheet-fed printing press, has supply roller to control feed motion of foil, so that foil is transported in transfer area in channel passage between roller and cylinder - Google Patents

Abstract

The device has an application unit (1) pictorially applying a printed sheet with adhesive. A coating module (2) transfers imaging layers from a carrier foil (5) to the sheet in a transfer gap (6) between an impression cylinder (4) and a pressing roller (3). A foil supply roller (8) supplies the foil to the module and leads the foil from the coating unit to move the foil in working direction. Feed motion of the foil is controlled by the supply roller, so that the foil is transported in a transfer area in a channel passage between the roller and cylinder without web stress change.

Description

The The invention relates to a device for transferring imaging layers from a carrier film on printed sheet according to the preamble of claim 1.

It is known to produce metallic layers on printed sheets by means of a film transfer process. So is in the EP 0 569 520 B1 a printing material and a printing apparatus using this material are described. In this case, a sheet-processing machine is shown, which has a feeder and a boom, wherein printing units and a coating module are arranged between the two units. In at least one of the printing units, an adhesive pattern is applied by means of the planographic printing process. This adhesive pattern is applied in a cold printing process and has a specific imaging subject. In the printing unit following the coating module with a counter-pressure cylinder and a press roller, a film guide is provided. This is designed in such a way that a film strip or a transfer film is guided through the transfer nip of the coating module between the impression cylinder and the press roll from a film supply roll. The film strip is rewound on the outlet side after leaving the coating module. The transfer film has a carrier layer on which imaging layers such as metallic layers, for example of aluminum, can be applied. Between the metallic layer and the carrier film, a separating layer is provided, which ensures that the metallic layer can be removed from the carrier layer.

At the Transport of press sheets through the printing unit will print each sheet provided with an adhesive pattern. Thereafter, the sheet is through led the coating module, wherein by means of the press roll the resting on the impression cylinder sheet with the sheet material is associated. It goes down metallic layer a close connection with the adhesive provided Areas on the sheet.

To the further transport of the printed sheet adheres to the metallic Layer only in the area provided with the adhesive pattern at. The carrier film is thus the metallic layer in Removed range of adhesive patterns. The consumed in this way Transfer film is wound up again. The print sheet is coated Condition designed.

It is known such coating modules, for example in printing units of printing presses. A disadvantage of the known devices is that they are not flexible.

task The invention is therefore to provide a device by means of which the transfer of an imaging layer z. B. a metallization layer, on a sheet can be done safely, economically and accurately, the device being for an extended range of applications should be manageable.

The Solution of this problem results in a device according to the features of claim 1.

In Advantageously, the device is characterized a web tension maintaining device in the transfer area This results in an extended range of applications for the process of cold foil stamping. The makeready shortening is achieved by prepared press cylinder lifts. In addition, register automation can be introduced become.

The Device is also advantageously used to a Improvement of the film utilization to achieve that the Transfer film in one or more Teilfolienbahnen lesser width is split. In combination with the aforementioned method can so different types of films are used side by side.

In Advantageously, a control of the transfer film such take place that when passing through a gripper of the sheet-guiding Impression cylinder receiving cylinder channels of the film feed is stopped, the press roll then under the transfer film passes through.

advantageously, It is also possible to have several coating modules within to provide a sheet-processing machine in a row. In order to the application of different imaging coatings or Metallization layers within a subject take place successively. It is possible to use a single adhesive pattern with all picture element elements, the imaging layers next to each other transferred to. It is also possible a first Adhesive pattern in a first coating module with a first to provide imaging coating or metallization and superimposed in the following another, the first enclosing Apply adhesive pattern and with another imaging coating or to provide metallization.

in the Below, the invention is illustrated in more detail with reference to figures.

there shows:

1 a basic representation of a printing press with a film transfer device,

2 the construction of a coating module with a film transfer device

3 the transfer area of the coating module and

4 an inventive arrangement for film guidance.

• – Ein Druckbogen wird zunächst mit einem flächigen oder bildgebenden Klebstoffmuster versehen (Druckwerk als Auftragwerk 1).
• – Im Folgedruckwerk wird der Druckbogen gemeinsam mit einer Transferfolie 5 unter Pressung durch einen Transferspalt 6 geführt, (Beschichtungswerk 2).

1 shows parts of a sheet-fed rotary printing press, which contains two printing units and is used for the following purposes:

• - A printed sheet is first provided with a two-dimensional or imaging adhesive pattern (printing unit as Auftragwerk 1 ).
• - In the following printing unit, the printed sheet is combined with a transfer film 5 under pressure through a transfer nip 6 guided, (coating plant 2 ).

The commissioned work 1 can be a known offset printing unit with an inking unit 11 , a plate cylinder 12 and a blanket cylinder 13 be. The blanket cylinder 13 acts with an impression cylinder 4 together.

The coating plant 2 can also be formed by an offset printing unit. The transfer gap 6 in the coating plant 2 is through a press roll 3 and an impression cylinder 4 educated. The press roll 3 may correspond to the blanket cylinder. The press roll 3 can also correspond to the form cylinder of a paint module. Within the coating plant used for the film transfer 2 is a track guide 14 shown for transfer foils. The transfer foil 5 is protected by protective devices 15 of the coating plant 2 on and executed again.

The foil supply roll 8th is the coating plant 2 assigned on the side of the sheet feeder. The foil supply roll 8th has a rotary drive 7 for continuous controlled feeding of the transfer film to the coating unit 2 on. In the film feeder can deflection or tension rollers for guiding the transfer film 5 in a substantially constant tension against the press roll 3 be provided. On the downstream side of the printing unit is a film collecting roll 9 provided for the used sheet material. A rotary drive 7 at the foil collecting roll 9 is always advantageous. It may even be provided that the transfer film 5 by means of the rotary drive 7 conveyed on the outlet side and held tight on the inlet side by means of a brake.

The press roll 3 (As blanket cylinder or forme cylinder or separate press roller) carries on its surface a compressible or damping, z. B. also provided with a compressible intermediate layer element. The press roll 3 can do this with a press cover 10 For example, be provided as a plastic coating, comparable to a blanket or blanket, which is held in a cylinder channel on jigs.

To ensure the efficiency of the coating process can be provided, the film feed of the transfer film 5 from the film supply roll 8th to the transfer gap 6 and to the foil collecting roll 9 is progressively controllable, with the transfer film 5 is then stopped if no transmission of imaging or covering layers is to take place.

The associated device preferably includes a corresponding feed control for the transfer film 5 , which ensures that at least that in the area of the press roll 3 and the impression cylinder 4 lying part of the film web is changed in its web guide as long as the cylinder channel passes. This will be later in 2 to 4 Details explained.

A further improvement of the film utilization of the type described results when the transfer film 5 is divided into one or more Teilfolienbahnen lesser width. Thus, with appropriate control by means of the device or devices for timing the film feed each of the partial film webs, the utilization of the transfer film 5 be improved even with zonally different lengths coating areas within a sheet.

Furthermore, in the film application module thus formed from the applicator 1 and the coating plant 2 dryer 16 be provided, by means of which the adhesive application or the entire film coating can be dried. Here come z. B. UV dryer in question.

Furthermore, the film application module can be a monitoring device 17 to scan the sheet surface included. The monitoring device 17 allows the evaluation of image contents of the coating and the detection of defects in the film coating. Such a monitoring device can also be provided in conjunction with the printing press, in which the film application module is integrated. Then it can be arranged for example in the sheet delivery of the printing press or a last printing unit.

The transport of the transfer film 5 can be on or between film guide rollers 14 by examination the web tension of the film web 5 be monitored. In a Fo lienbahnführung are one or more web tension measuring devices 19 intended.

Furthermore, to stabilize the film web 5 between a first deflection roller and a first inlet roller to the transfer station, a stabilizing device 30 be arranged to flutter the film web 5 to reduce. The stabilizer 30 has z. B. two rotatably mounted rollers, which is for variable adjustment of the wrap angle of the film web 5 is provided on the guide rollers, so that the guiding action and the damping effect on the film web 5 is adjustable depending on the operating state. The setting of the stabilizer 30 Can be used in conjunction with web tension control devices 19 and possibly a sensor device 20 be made for web break monitoring.

• 1. Ein Bahnzug oberhalb eines vorgebbaren Minimalwerts wird als Signal für Vorhandensein der Folienbahn 5 gewertet und der Maschinensteuerung zugeführt.
• 2. Ein Überschreiten des Maximalwerts des vorgebbaren Bahnzugs wird über Tänzerwalzen 18 oder Rollenantriebe 7 der Folienvorrats- 8 bzw. -sammelrolle 9 reduziert. Damit sind unzulässige Bahndehnung oder Bahnriss vermeidbar.
• 3. Bei Unterschreiten des minimal vorgebbaren Bahnzugs wird überprüft, ob die Bahnspannungsregelung noch aktiv ist. Ist eine Erhöhung der Bahnspannung über Tänzerwalzen 18 oder eine Bremse nicht möglich, wird Bahnriss erkannt.

Electrical signals of the web tension measuring devices are evaluated. Various operating states are possible for this:

• 1. A web train above a predetermined minimum value is used as a signal for the presence of the film web 5 evaluated and fed to the machine control.
• 2. Exceeding the maximum value of the predeterminable web train is over dancer rolls 18 or roller drives 7 the foil supply 8th or collecting roll 9 reduced. Thus, impermissible web elongation or web break can be avoided.
• 3. If the minimum specified tension is undershot, it is checked whether the web tension control is still active. Is an increase in web tension over dancer rolls 18 or a brake is not possible, web break is detected.

The additionally obtained information about the web tension as the actual value, in particular in the context of the aforementioned evaluations, can be used for the control of the printing or transfer process. For this purpose, the system can be coupled to a control station of the printing machine, via which the setpoint values for maximum and minimum web tension can be entered. This may depend on the type of transfer film used 5 and the pressure or transfer conditions in the coating module 2 be dependent on the properties of the printing material, the adhesive or the press fabric.

The necessary data can be read via interfaces directly from data carriers to film supply rolls and by means of parameter values from the setting of the transfer process on the coating module 2 to be changed.

The method relating to the film transfer is described in the described printing or application machine according to 1 as follows:
It is intended, at least in one the coating plant 2 following printing unit 50 apply a color print on the imagewise coated with a metallized layer sheet. Here, the sheet is from the coating plant 2 from the impression cylinder 4 via a sheet transfer drum or a sheet transfer unit to an impression cylinder 40 of the printing unit 50 transferred.

The printing unit 50 has as usual in offset printing the impression cylinder 40 , a rubber or blanket cylinder associated therewith 41 and a plate cylinder associated therewith 43 on. The plate cylinder 43 Here are shown schematically an inking unit and a dampening system assigned. Between impression cylinder 40 and blanket cylinder 41 is another nip 60 educated. In this pressure gap 60 becomes printing ink from one on the plate cylinder 43 clamped pressure plate 44 out over one on the blanket cylinder 41 arranged cover 42 applied to the sheet.

The gap of the pressure gap 60 between the surfaces of the blanket cylinder 41 and the impression cylinder 40 is with the help of the blanket cylinder 41 associated adjusting devices 45 adjustable. This is usually spoken of in the area of offset printing from a Druckbeistellung, as said setting refers to the thickness of the processed material to be processed, in the printing gap 60 to be printed. For this purpose, a printing pressure is necessary to the ink from the blanket cylinder 41 on the on the impression cylinder 40 transferred substrate.

The settings in relation to the transfer gap 6 done by means of other control devices 46 that of the press roll 3 assigned.

The adjusting devices 45 . 46 are commonly used in offset printing on printing blanket or blanket cylinders of printing units or on cylinders of varnish modules.

In 1 the locations of the print jobs or press releases are designated DB1 and DB2 and coincide with the transfer 6 or printing gap 60 ,

Furthermore, as the surface of the press roller 3 a contoured or segmented pressing surface in the press fabric 10 be provided. For this purpose, instead of a full-surface pressing area on one or more areas to be coated limited segmental pressing areas on the press roll 3 used. In combination, different types of film can be used side by side. This allows surfaces of different film color or different smoothness or texture to be created.

In a continuous processing of the film web 5 without clocking is a defect in the surface of the press roller when passing through the cylinder channel 3 effective, so that there the web tension is lowered. This can be reduced by an insert in the cylinder channel, which at least partially covers the defect. Nevertheless, a continuous disturbance in the web tension is initiated by the channel passage. This should be avoided.

For the film feed (and the discharge) is usually the drive of the film rolls 8th . 9 continuously provided, as the mass of film rolls 8th . 9 too big for a quick change of the drive movement. This results in braking the film web to re-accelerate in the transfer area in the supply and discharge of the film web 5 opposite to the movement of the film rolls 8th . 9 excess or missing film lengths.

Therefore, the invention proposes that in the case of continuous Nachförderung or removal of the film web 5 accumulating excess or missing pieces of track in the channel passage of cylinder channels 22 . 23 on the press roller 3 and the impression cylinder 4 Buffers can. These are basically already with the dancer rollers 18 as a variant of foil stores be written. The dancer rollers 10 but are not accurate enough to the described in the described high-speed clocking in the film transfer process controllable, especially since they usually far away from the place of consumption and close to the film roll 8th . 9 are arranged to maintain the web tension there.

In 2 is a film transfer module accordingly 1 shown. Here are the dancer rollers 18 arranged to regulate the web tension. To compensate for minor changes in the film promotion, as in the channel passage during the film promotion in the transfer area (range of film transfer between press roll 3 and impression cylinder 4 ) with continuous film consumption (no channel clocking, format clocking, timing must be provided on embossed areas), are in addition to the known film guide rollers 14 in addition to the inlet of the fresh film web 5 in the transfer gap 6 and after the exit of the used film web 5 from the transfer gap 6 one foil deflecting roller each 80 respectively. 90 arranged.

In 3 is an enlarged view in the coating plant 2 shown. Here are the film guide rollers on the one hand 14 to the definition of the railway path shown. Furthermore, in the area of the film feed to the transfer area with the transfer nip 6 a film deflecting roller 80 intended. On the outlet side of the transfer area is a film deflecting roller 90 shown. These film deflecting rollers 80 . 90 can be a transversely to the course of the transport direction of the film web 5 perform directed compensation movement. The compensation movement will be explained later. By means of film deflecting rollers 80 . 90 becomes the web path of the film web 5 constantly extended and shortened. During the passage of the channel, the film deflection rollers can 80 . 90 perform a compensating movement to shorten the web path and so release a piece of film web to compensate for this movement against the Abförderbewegung.

In 4 is the section of a Folienumlenkwalze 80 shown in detail. The explanations apply mutatis mutandis to the Folienumlenkwalze 90 , The film deflecting roller 80 is with a double surface contour 81 . 82 provided a guide of the film web 5 allowed in different heights. For this purpose, the film deflecting roller 80 driven in rotation, so that the film web constantly between the inwardly offset surface contour 81 and the roller surface of the corresponding increased surface contour change is performed. In this case occurs in relation to the web guide between the film guide rollers 14 and the press roll 3 steadily an extension and shortening of the railway track, which is characterized by the shift to the surface contours 81 . 82 results. The relocation is in 4 dashed and drawn through. Here, the solid position of the film web 5 during the transfer process (see 3 ) normal position, because then the film web 5 also in the transfer gap 6 from the press roll 3 and the impression cylinder 4 is fully managed. The while passing through the cylinder channels 22 . 23 occurring relaxation of the film web 5 becomes in the strichliierten position of the film web 5 to 4 by the displacement of the film web 5 on the surface contour 82 compensated. Here is the height difference of the surface contours 81 . 82 the possible stroke of the film web 5 to compensate for the foil relaxation at the channel pass.

The surface contours 81 . 82 can be the difference in run lengths between the cylinder channels 22 . 23 and the full surface of the press roll 3 be adjusted so that there is a same tact between the rotation of the press roll 3 with the cylinder channel 22 and the film deflecting rollers 80 . 90 and a continuous rotational movement of the film deflecting rollers 80 . 90 results. A contouring with a larger stroke in a small Roll diameter may be due to a non-uniform drive of the Folienumlenkwalzen 80 . 90 , be compensated. The then between film web 5 and the film deflecting rollers 80 . 90 Forcibly occurring slip can be achieved by appropriate surface treatment of the film deflection rollers 80 . 90 be enabled. Because the film web 5 with the uncoated back on the film deflection rollers 80 . 90 it is not harmful to slip here.

1

commissioned

2

coating module

3

press roll

4

Impression cylinder

5

Transfer film / sheet

6

transfer nip

7

roller drive

8th

Film supply roll

9

Foil composite role

10

Press covering

11

Inking / dampening unit

12

plate cylinder

13

Printing blanket / blanket cylinder

14

Folienleiteinrichtung

15

Printing plant security

16

dryer

17

Inspection device / monitoring system

18

dancer roll

19

Bahnspannungsüberwachungl

20

Web break monitoring

21

Druckzylinderblasvorrichtung

22

cylinder gap

23

cylinder gap

30

stabilizing device

40

Impression cylinder

41

Blanket cylinder

42

Blanket / blanket

43

plate cylinder

44

printing plate

45

setting device

46

setting device

50

printing unit

60

nip

80

Folienumlenkwalze

81

surface contour

82

surface contour

90

Folienumlenkwalze

DB1

printing pressure

DB2

printing pressure

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - EP 0569520 B1 [0002]

Claims (8)

Device for transfer of image-forming layers from a carrier foil to printed sheets at least with an applicator ( 1 ) for an imagewise coating of the printed sheets with an adhesive and with a coating module ( 2 ) for transferring the imaging layers from the carrier foil to the printed sheet in a transfer nip ( 6 ) between an impression cylinder ( 4 ) and a press roll ( 3 ), wherein the carrier film with the coated side in contact with the printed sheet together with this through the transfer nip ( 6 ) is feasible and thereby the image-forming layers are imagewise transferable to the printing sheet, and with a device for feeding the transfer film ( 5 ) to the coating plant ( 2 ) and for removal from the coating plant ( 2 ) with a drive for moving the transfer film in the working direction, characterized in that the feed of the transfer film ( 5 ) is controllable by means of a film guide such that the transport of the transfer film ( 5 ) in a transfer gap ( 6 ) of the coating plant ( 2 ) transfer area at a channel passage between press roll ( 3 ) and impression cylinder ( 4 ) runs without web tension change. Apparatus according to claim 1, characterized in that at least one compensation device the transfer area before the inlet of the film web ( 5 ) in the transfer gap ( 6 ) and / or after the outlet of the film web ( 5 ) from the transfer gap ( 6 ) is provided. Apparatus according to claim 1 or 2, characterized in that the film web ( 5 ) in time with the processing of the film transfer controllable conveyors for moving the film web ( 5 ) are assigned transversely to the conveying path. Apparatus according to claim 1 to 3, characterized in that the conveying devices as a film web ( 5 ) leading Folienumlenkwalzen ( 80 . 90 ) are formed. Apparatus according to claim 4, characterized in that the film deflecting rollers ( 80 . 90 ) as drivable rotating rollers with circumferentially formed surface contours ( 81 . 82 ) are. Apparatus according to claim 4, characterized in that the film deflecting rollers ( 80 . 90 ) at least one surface contour ( 81 ) for guiding the film web ( 5 ) in the process state of the film transfer during installation of the film web ( 5 ) on the closed surface of the press roll ( 3 ) exhibit. Apparatus according to claim 4, characterized in that the film deflecting rollers ( 80 . 90 ) at least one surface contour ( 82 ) for guiding the film web ( 5 ) to streamline the film web ( 5 ) in the process state of the channel passage between the press roll ( 3 ) and the impression cylinder ( 4 ) without guiding the film web ( 5 ) on the closed surface of the press roll ( 3 ) exhibit. Apparatus according to claim 1 to 7, characterized in that the transfer film ( 5 ) is subdivided into one or more sub-foil webs of lesser width and that the sub-foil webs are positioned or juxtaposed to the transfer nip ( 6 ).