EP2106347A1

EP2106347A1 - Film guidance in a film transfer unit

Info

Publication number: EP2106347A1
Application number: EP07856351A
Authority: EP
Inventors: Uwe Püschel; Guido Reschke; Jürgen Schölzig
Original assignee: Manroland AG
Current assignee: Manroland AG
Priority date: 2006-12-29
Filing date: 2007-12-04
Publication date: 2009-10-07
Also published as: JP2010514591A; CN101605660A; DE102006062012A1; WO2008080487A1

Abstract

The aim of the invention is to simplify the supply of film to a coating station for transferring image-providing layers from a transfer film onto a printing material. In order to allow the film to be guided through protectors and a printing gap, film guiding elements are inserted into the coating system. The film is preferably guided past a pressure roller in a substantially tangential manner. The film guiding elements can be inserted into already existing mountings.

Description

Folienführuπg in a film transfer unit

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

It is known to produce metallic layers on printed sheets by means of a film transfer process. Thus, EP 0 569 520 B1 describes a printing material and a printing device using this material. In this case, a sheet-processing machine is shown, which has a feeder and a boom, between two units printing units and a coating unit are arranged. 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 unit 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 passed through the transfer nip of the coating unit between the impression cylinder and the press roll from a film supply roll. The foil strip is rewound on the outlet side after leaving the coating unit. 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.

When printing sheets are transported through the printing unit, each sheet is given an adhesive pattern. Thereafter, the sheet is passed through the loading lamination, wherein by means of the press roller on the impression cylinder resting sheet is brought into contact with the sheet material. In this case, the downwardly lying metallic layer enters into a close connection with the areas provided with adhesive on the printed sheet. To the further transport of the printed sheet adheres to the metallic layer only in the area provided with the adhesive pattern. The carrier film is thus removed from the metallic layer in the region of the adhesive pattern. The used in this way transfer film is wound up again. The print sheet is laid out in the coated state.

It is known to use such coating units, for example in printing units of printing presses. A disadvantage of the known devices is that they are not flexible and that the supply of the transfer film is complicated and difficult to handle.

The object of the invention is therefore to provide a device by means of which the transfer of an imaging layer, e.g. a metallization layer on a sheet can be done safely, economically and accurately, the device should be easy to handle.

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

Advantageously, a feed device is used for guiding the transfer film, in which the transfer film is guided during feeding to the transfer nip by a modular guide system.

The device can also be advantageously used in order to improve the use of the film by dividing the transfer film into one or more partial film webs of lesser width. In combination with the above-mentioned method, it is thus also possible to use different types of film side by side.

According to the invention, recording devices or aggregate assemblies existing within a printing unit are used to receive or integrate guide devices for film transport.

Thus, a guide for a removable from the printing blanket blanket washing device in the machine frame permanently mounted recording devices exhibit. In this recording devices Folienleiteinrichtungen be used with the receiving devices corresponding holding elements. The corresponding assembly or disassembly is preferably done without tools. The assembly is preferably carried out in sheet travel direction from the printing unit broadside.

The same applies to a printing cylinder blowing device provided in the printing unit, which serves for sheet guiding. Here, the assembly of guide devices can optionally also be made on the face side to a printing unit by insertion into mounting holes. Furthermore, an integrated cardboard guide or blowing bar can be used directly as a guide for guiding the transfer film into the transfer nip. Correspondingly designed deflection rollers can be adjusted so that the entry angle of the film web is adjustable in the transfer nip. A film guide may be on the outlet side of the film web, if necessary, a channel o- an active protection against intrusion integrated on a printing unit protection integrated. The printing unit protection can furthermore be adjustable into a guide position, in which the channel for discharging the film web at the guide devices is released. This setting can be done automatically when operating with foil application. During normal machine operation, the print protection also automatically closes the channel again.

A film guide may be integrally formed on the outlet side of the film web, if necessary, an active protective device against engagement as an adapter element with quick-release device on a printing unit protection. The function can be designed as described above. In this case, the automatic control can be connected to the insertion or removal of the adapter element on the printing unit protection.

In the following the invention is illustrated in more detail with reference to figures.

Showing:

1 shows a printing machine with a film transfer device,

Figure 2 of a film guide on a press roll and Figure 3 a film guide in detail.

Figure 1 shows a sheet-processing machine, here a printing machine with two printing units. With the printing units, a cold foil transfer process is performed. In this case, a sheet is first provided with an imaging adhesive pattern (applicator 1 with inking / dampening unit 11, plate cylinder 12 and rubber or blanket cylinder 13). Thereafter, a transfer sheet 5 is passed through a transfer nip 6 in the following printing unit together with a printing sheet, wherein the transfer sheet 5 is pressed in the transfer nip 6 against the sheet (coating unit 2 with press roller 3 and impression cylinder 4).

The transfer nip 6 in the coating unit 2 is formed by a press roll 3 and an impression cylinder 4. The press roller 3 may be the blanket cylinder of an offset printing unit or the forme cylinder of a lacquer module of a sheet-fed press, preferably a sheetfed offset press. Transfer films 5 have a carrier layer and a release layer to form an imaging layer. The separating layer serves to facilitate lifting of the imaging layer from the carrier layer. The image-forming layer may be a metallized layer or a glossy layer or a texture layer or a colored layer or a layer containing one or more image patterns. The film supply roll 8 is assigned to the coating unit 2 on the side of the sheet feed. The film supply roll 8 has a rotary drive 7. The rotary drive 7 is required for the continuous controlled feeding of the transfer film to the coating unit 2 and is therefore controllable. Furthermore, a deflecting or tensioning roller is provided in the region of the film feed. Thus, the film web of the transfer film 5 is always held in the same tension against the press roller 3. On the downstream side of the coating unit 2, a film collecting roller 9 is arranged, is wound on the used sheet material again. For optimized production, a rotary drive 7 is provided, which is controllable. The transfer film 5 can also be moved by the rotary drive 7 on the discharge side and kept taut on the inlet side by means of a brake.

For the transfer process of the imaging example metallized layer on the substrate in the transfer nip 6 is essential that the surface of the press roll. 3 is equipped by means of a compressible, damping element. The press roll 3 can be provided with a press fabric 10, for example, as a plastic coating, comparable to a blanket or blanket. The press fabric 10 is held in a cylinder channel on clamping devices. The press fabric 10 is provided to improve the transfer properties in the transfer nip 6 with a specific elasticity or compressibility, which can be generated by means of conventional printing blankets or combined coverings of a blanket and a pad.

Furthermore, one or more pressing areas limited to subject areas can be provided directly on the press roll 3 or on the press fabric.

The arrangement of a press roll can also be carried out within an integrated film transfer module FA together with a processing unit within the scope of the invention. For this purpose, a printing unit (here, for example, applicator 1 in Fig. 1) used for the adhesive application and the printing nip of the adhesive application on the same impression cylinder 4 of this printing unit downstream of a separate press roller can be arranged. Alternatively, an additional device for adhesive application to the impression cylinder 4 can be arranged upstream of the transfer nip 6 on a printing unit (here, for example, coating unit 2 according to FIG. Both embodiments result in a compact design.

For intermediate or subsequent treatment of the adhesive layer or of the transfer image applied thereto, driers 25 can be provided downstream of the applicator 1 or the coating unit 2. Here in particular in connection with a corresponding adhesive UV dryer in question.

To control the applied transfer image, the coating unit 2 can be provided downstream of a monitoring system 26 for sheet inspection. Defects in the cold foil stamping process can be identified by means of such a monitoring system 26 in addition to errors in the transfer image.

To ensure the efficiency of the coating process, it may be provided that the film advance of the transfer film 5 from the film supply roll 8 to the transfer nip 6 and to the film collection roller 9 is controllable such that as far as possible the transfer film 5 is then stopped, if no transfer of the imaging layer should take place:

For this purpose, a control of the transfer film 5 can be carried out such that the transport of the transfer film 5 is stopped when a gripper of the sheet-guiding counter-pressure cylinder 4 accommodates the cylinder channel and a correlating cylinder channel of the press roller 3. The timing of the film feed can be executed in accordance with a necessary acceleration or braking of the film supply roll 8 or film collection roller 9 via so-called dancer rollers 18 or the rotary drives 7 of the film rolls 8, 9.

An 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 can be improved even with zonally different coating areas within an arc.

According to the invention for this purpose, a device shown in Figure 2 for Folienfüh- tion on a press roll 3 is provided, which is substantially tangential to

Press roll 3 is guided by the transfer nip 6 with the impression cylinder 4 of the coating plant 2. These include a corresponding film guiding device 20 and a film feeding device 30, which are described below, and guide the film web 5 in the transporting direction T through the coating mechanism 3.

Provided is a film guide 14 which is aligned approximately tangentially between the press roll 3 and the impression cylinder 4 and forms a wrap of the press roll 3 by less than 90 degrees. This achieves a defined application and guidance of the film web 5 on the press roller 3 and at the same time the necessary conditions for a possible film timing or film discontinuity in the transfer nip 6 during a passage through the channel in the transfer nip 6, but also for the use of narrow film webs 5, created. The film guide 14 for a film web 5 or partial film webs 19 includes on the feed side to the transfer nip 6 starting from an inlet opening 16 on a printing unit protection 15 some guide rollers 22. These can be arranged differently depending on the configuration of the printing unit. The film guide 14 may be arranged in accordance with FIG. 2 in conjunction with a Druckzylinderblasvorrichtung 36. This has blow holes for the formation of blow jets S, which are used on the one hand to guide a printing material B on the impression cylinder 4 when entering the transfer nip 6. The Druckzylinderblasvorrichtung 36 may also be directed to the pneumatic support on the film web 5 in order to spread this wrinkle-free and tight. If necessary, one of the guide rollers 22 for guiding the film web 5 can be replaced by means of an appropriate arrangement of the printing cylinder blowing device 36. Part of the film guide 14 can furthermore be a mechanical or pneumatic guide element on the edge of the printing mechanism protection 15 in the region of the inlet opening 16 which seals the film web 5 when running into the coating unit 2 taut and holds. The film web 5 is also passed to a cleaning device 39, which is assigned to the press roller 3. The cleaner 39 removes stains resulting from the film processing from the press roller 3.

Another part of the film guide 14 includes on the discharge side of the transfer nip 6 starting at an exit opening 17 on a printing unit protection 15 further guide rollers 32, 34. These may in turn be arranged differently depending on the configuration of the printing unit. The film guide 14 is arranged here in conjunction with an inlet protection 33. This serves to secure the transfer gap 6 against unintentional interventions. The film web 5 can be guided around the inlet protection 33 or through openings in its contour. The guide rollers 32, 34 may be arranged in conjunction with the printing unit protection 15, so that they take along the film web 5 during its displacement. Alternatively, the guide roller 34 may be arranged to be adjustable, so that the wrap angle of the film web 5 on the press roller 3 is adjustable. In this context, it is also important that the transfer film 5 can come into contact with the counter-pressure cylinder 4 during a channel pass in the transfer nip 6 with grippers G. The grippers G hold a sheet B at its front edge on the impression cylinder 3 for secure transport through the transfer nip 6 fixed. With their so-called gripper back in the region of the pinching of the edge of the printing sheet B, they project to a slight extent over the circumference of the counter-pressure cylinder 4. Coordination with a channel likewise present on the press roll 3 is selected such that its associated edge comes into contact with the impression cylinder 4 only after the contour of the gripper G has arrived. However, since the film web 5 is stretched freely over the channel of the press roll 3, the grippers G can press into the film web 5 which is not supported there. For this purpose, it is advantageous to make the wrap angle of the film web adjustable in order to achieve an early separation of the gripper G from the film web 5 in the channel pass in the transfer nip 6. Preferably, the gripper G are formed with a projecting in the smallest possible extent over the circumference of the impression cylinder 4 contour. Here, systems of grippers G can be used, the total are permanently or cyclically adjustable radially to the impression cylinder 4, so that the height of the gripper G can be minimized over the cylinder contour. The film guide can be further supported by the fact that the cylinder channel of the press roll 3 is provided with a cover for largely cylindrical complement of the surface of the press roll. As a result, the film web 5 is indeed brought closer to the impression cylinder 4 in the area of the gripper G, but the film guide is overall more continuous and quiet.

In addition, the guide of the transfer film 5 can be influenced by a further guide roller, which is arranged in the region after the film removal from the film supply roll 8. By means of this guide roller 38, which is adjustable in its axial position relative to the position of the axis of the film supply roll 8, unevenness or irregularities of the film flow from the film supply roll 8 can be compensated for feeding the film web 5 to the film guide 14. According to Figure 3, a slide-in cassette 21 is provided with guide elements made of metal and / or plastic (CFK). As guide elements by means of integrated initially rotating guide rollers 22 are provided. Air-purged blow rods or blow rods made of sintered metal with air outlet can also be used for the film web 5, so that the transfer film 5 is carried on an air cushion. The guide rollers 22 may be made of aluminum or reinforced plastic, such as CFRP, so they are easy to build and thus enter the lowest possible stress in the film web 5. The guide rollers 22 may be surface-coated, for example with Teflon or other the adhesion of the transfer film 5-reducing coatings. The guide rollers 23 preferably form a guide channel 24 and serve both for guiding the film (deflection) during the film run and also as an insertion aid in the film feed at the beginning a production process.

The drawer cassette 21 may be associated with a printing cylinder blowing apparatus or the drawer cassette 21 may be configured together with the printing cylinder blowing apparatus as a unit. Thus, the drawer cartridge 21 can be used simultaneously for sheet guiding on the impression cylinder 4.

The film guiding device 20 can furthermore be supported by means for generating blowing air. For this purpose, it may have at the film exit to the transfer nip 6 between the press roller 3 and the impression cylinder 4, a blowing device 16 which directs one or more bundled or fan-shaped air jets S for sheet guiding below the film web 5 on the substrate. In particular, the combination comes with a Druckzylinderblasvorrichtung in question.

The film guiding device 20 can have easily replaceable guide elements, for example the guide rollers 22 or the guide plates 23, at the particularly critical deflection or exit positions, so that the wear parts can easily be replaced during service. The Folienleiteinrichtung 20 may be associated with a carton guide or integrated with this in a structural unit to prevent contact between the film web 5 and substrate (cardboard) even before their entry into the transfer nip 6 between the press roller 3 and the impression cylinder 4.

Outlet side, i. in the transport direction of the film web 5 after the transfer nip 6 between the press roller 3 and the impression cylinder 4, above the film web 5, a support plate 29 is optionally applied with blown air, arranged. Below the film web 5, a baffle 27 can be temporarily inserted for film feeding.

On the outlet side, a film deflection is preferably in an existing printing unit protection 15 of the coating unit 2, for example. a protection for an automatic plate feeder, integrated. Here, in turn, the use of a guide roller 32 or a coated guide plate 28 or a possibly luftumspülten deflection is possible.

During operation of a printing unit as a coating unit 2 with film webs 5, said printing unit protectors 15 can automatically be moved into a defined, preselectable and lockable opening position, so that an appropriately dimensioned inlet opening 16 or outlet opening 17 is created for the film web 5.

For foil insertion, a guide or drawstring or strip of metal or plastic or foil is attached to the foil leading edge of the unwinding roll. By means of this auxiliary device, the film web 5 can be pushed or pulled through the film guide 20 within the coating unit 2.

The coating unit 2 can also be assigned a partially or fully automated feeder device 30, eg by means of a cable pull, chain hoist, belt. In this case, both the entire path of the film web 5 or only the area within the coating plant (printing unit of a sheet-fed offset printing machine or paint module in a sheet-fed printing machine). By means of the described film guiding tion 14 or 20, both a film feed and a film guide within a coating unit 2 are made possible. This ensures operability at all times and setup times are minimized. Finally, by means of the film guide 14 and 20, an extensive automation of all work and settings in the film insertion and film feedthrough possible.

According to the invention, existing recording devices or aggregate assemblies are used within a printing unit to receive or integrate guide devices for film transport. Thus, a guide for a removable from the printing unit blanket washing device U in the machine frame permanently mounted recording devices have, can be used in the Folienleiteinrichtungen with corresponding holding elements. The assembly is preferably carried out in sheet travel direction from the printing unit broadside. The same applies to a pressure cylinder blowing device V provided in the printing unit. Here, the mounting of the guide can be effected on the face side to form a printing unit by insertion into mounting openings.

Furthermore, an integrated cardboard guide or blow rod X can be used directly as a guide of the transfer film in the transfer nip. A film guide may be on the outlet side of the film web, if necessary, a channel o- an active protective device Y against engagement forming in the vicinity of a printing unit protection 15 integrated.

A film guide can be integrally formed on the outlet side of the film web, if necessary, an active protective device against engagement as an adapter element Z with quick-release device on a printing unit protection.

LIST OF REFERENCE NUMBERS

1 applicator

2 coating unit

3 press roll

4 impression cylinders

5 transfer foil / foil web

6 transfer gap

7 roller drive

8 foil supply roll

9 foil collecting roll

10 press clothing

11 inking / dampening unit

12 plate cylinders

13 rubber / blanket cylinder

14 film guide

15 print protection

16 blowing device

17 inlet / outlet opening

18 dancer roller

19 partial film web

20 film guide

21 slide-in cassette

22 guiding role

23 guide plate

24 guide channel

25 dryers

26 monitoring system

27 baffle

28 guide plate

29 support plate 30 film feeding device

31 pressure roller

32 guide role

33 Intake protection 34 Guide roller

35 bracket

36 pressure cylinder blowing device

37 blowing device

38 guide roller 39 cleaning device

S blowing jet

G gripper

B substrate T Transport direction

Claims

claims

1. An apparatus for transferring image-forming layers from a carrier film to printing sheets at least with an applicator unit (1) for image-wise coating a printed sheet with an adhesive and with a coating unit (2) for transferring the image-forming layers from the carrier film to the printed sheet, wherein the coating module (2) comprises a counter-pressure cylinder (4) and a press roll (3) forming a common transfer nip (6), and further wherein the support film is passable around the press roll (3) such that it engages with the press roll (3) coated side on the on the

Impression cylinder (4) guided printed sheet placed and under pressure together with the sheet through the transfer nip (6) between the press roller (3) and impression cylinder (4) is guided, so that the image forming layers after the exit of the sheet from the transfer nip (6) Area of the provided with adhesive image areas adheres to the sheet and is lifted from the carrier sheet, characterized in that in the coating unit (2) one or more film guides (14) or Folienleiteinrichtungen (20) for feeding the web of the carrier film (5) to the transfer nip (6) are provided as exchange elements against functional elements of a printing module forming the coating module (2).

2. Apparatus according to claim 1, characterized in that in the coating unit (2) a film guide (14) with one or more Folienleitelementen for deriving the path of the carrier film (5) from the transfer nip (6) are provided away.

3. Apparatus according to claim 2, characterized in that Folienleitelemente, preferably in the form of guide rollers (32, 34) and / or baffles (27, 28, 29), as a unit in the coating unit (2) and / or on a printing unit protection ( 15) can be used detachably or convertible are provided.

4. The device according to claim 3, characterized in that the film guiding elements have receiving devices which correlate with holders of in the printing unit of the coating module (2) removably arranged functional units, so that the Folieleitelemente detachably applicable or convertible in the coating module (2) forming printing unit are attachable.

5. Apparatus according to claim 1 to 3, characterized in that the Folienleiteinrichtung (14, 20) as a unit in the manner of a slide-in cassette (21) in the coating unit (2) releasably lockable insertable bar and / or provided reversible.

6. Apparatus according to claim 5, characterized in that the Folienleiteinrichtung (14, 20) forms a structural unit with one of the surface of the impression cylinder (4) associated Bedruckstoffleitvorrichtung.

7. The device according to claim 6, characterized in that the film guiding device (14, 20) a structural unit with a directed onto the surface of the counter-pressure cylinder (4) Druckzylinderblasvorrichtung

(36).

8. Apparatus according to claim 6, characterized in that the guide device is provided with a blowing device, by means of which

Blasluft can be directed below the film web (5) against a guided on the surface of the impression cylinder (4) substrate.

9. Apparatus according to claim 6, characterized in that the guide device forms a structural unit with one of the surface of the impression cylinder (4) associated cardboard guide.

10. The device according to claim 6, characterized in that the guide device for receiving in the holder of the surface of the press roll (3) associated washing device is formed.

11. The device according to claim 6, characterized in that the guide device for receiving in the holder of the surface of the impression cylinder (4) associated blowing device is formed.

12. The device according to claim 6 to 11, characterized in that the guide device is designed as a guide roller or guide roller pair.

13. Device according to one of claims 1 to 12, characterized in that the transfer film (5) is divided into one or more Teilfolienbahnen lesser width and that by means of the Folienleiteinrichtung (20) the Teilfolienbahnen side by side the transfer nip (6) are supplied.

14. Device according to one of claims 1 to 13, characterized in that the Folienleiteinrichtung (20) comprises guide elements, by means of which the Teilfolienbahnen side by side the transfer nip (6) are fed.