DE102011088018A1 - Method and film transfer plant for applying cold foil material to a sheet material in a processing machine - Google Patents

Abstract

The invention relates to a method and a film transfer unit for applying cold foil material 7 to a sheet material 6 in a processing machine. The invention is based on the object of improving a method and a film transfer unit such that the quality of the film coating on a sheet material is improved and the available printing format is better utilized. This is solved by the cold foil material 7 is in a contact with the cylinder 1 can be transported in the conveying direction 3 at least in a press nip 10 on the impression cylinder 2, the holding means 5 are arranged for the sheet material 6 in a respective cylinder channel 4 within the lateral surface 17 and the sheet leading edge the sheet material 6 is fixed by means of the holding means 5 within the lateral surface 17 and a maximum printing format of the same sheet material 6 on the lateral surface 17 is arranged.

Description

The invention relates to a method and a film transfer work for applying cold foil material to a sheet material in a processing machine according to the preambles of the independent claims. The method and the film transfer unit are preferably used in a printing press or a coating machine for sheet material and are based on the principle of cold foil transfer.

A method and a device of this kind is out WO 2009/138335 A1 known. Accordingly, the cold foil material fed into the press nip is pressed onto the sheet material exclusively in a press nip, formed by a counterpressure cylinder guiding the sheet material and an adjacent cylinder, which has a variable axis position. For this purpose, the sheet material was previously coated imagewise with an adhesive. Following the press nip, the cold foil material and the image material coated with adhesive on the impression cylinder are conveyed congruently on the impression cylinder in the conveying direction at a wrap angle. At the wrap angle, at least the adhesive is exposed to radiation or drying and in the discharge direction after the wrap angle, the cold foil material is separated and removed in an outflow gap in the film substrate, the release layer and a non-imaging film layer and the sheet material bonded with adhesive and imaging film layer is on the Counter-pressure cylinder continued by means of holding means. The counter-pressure cylinder may have holding means for fixing an arc edge. In this case, the holding means can be arranged over the lateral surface of the impression cylinder protruding or within the lateral surface. For the formation of the holding means located within the lateral surface no further details are disclosed.

WO 2008/084191 A1 discloses a coating process comprising the steps of applying a curable lacquer layer to a substrate, pressing a film surface against the still wet lacquer layer, curing the lacquer layer while the film is being pressed thereon, and separating the film from the lacquer layer after the lacquer layer has hardened , For this purpose, a machine configuration is disclosed which comprises an upstream printing unit or a coating unit for the transfer of a curable lacquer layer to the substrate and a downstream printing unit or a coating unit for pressing the film surface against the still wet lacquer layer. Furthermore, the machine configuration comprises a curing unit for curing the lacquer layer while the film is pressed against this or the substrate and a substrate transport system for the coated substrate and the film, which separates the film from the lacquer layer after the lacquer has cured. The pressed against the coating layer film adheres by the tack or adhesion of the paint on the paint layer and in addition, a guide roller is arranged downstream, which realizes the Anpresskontakt the film with the paint layer on the substrate. The separation of the (unnecessary) film from the substrate takes place after passing through the guide roller. The printing material is guided by an impression cylinder, which has over the lateral surface protruding gripper.

In such protruding grippers can not be exploited in the incoming in the press nip film or the film, the maximum possible print size (benefit). The start of printing is thus counter to the conveying direction by a certain amount, a distance offset in the circumferential direction of the sheet material to "back". To this disadvantage points WO 2008/084191 A1 due to a new gripper construction protruding beyond the contours of the impression cylinder, the distance of originally y = 75 mm ( 4 ) up to x = 20 mm ( 3 ) should be reduced. The over the contour of the impression cylinder protruding gripper have in addition to the insufficient utilization of the benefits of the disadvantage that the gripper with the surface, ie the back of the gripper fingers, the sensitive film or film can contact and thus the film marks, ie it occurs Spotting on, may have. Markings of this kind noticeably impair the printing or finishing quality and can lead to waste.

The object of the invention is to improve a method and a film transfer unit of the type mentioned in such a way that the quality of the film coating on a sheet material improved and the available printing format is better utilized.

The object is solved by the training features of claim 1 and 2. Further developments emerge from the dependent claims.

A first advantage is due to the fact that the known method and the film transfer unit for the transfer of cold foil material can be improved to the extent that the maximum available printing format of a sheet material can be noticeably better utilized. This allows more benefits to be achieved from a sheet material and reduces material costs. The device comprises, inter alia, a counter-pressure cylinder designed as a sheet guiding cylinder and having at least one cylinder channel Holding means, preferably with grippers and supports with bearing surface. These holding means are arranged for fixing a sheet material in the gripper closure, especially the sheet leading edge of a respective sheet material, within a lateral surface in the respective cylinder channel. The impression cylinder can be simply large (one-turret impression cylinder) or double or multiple-sized (½-turn or 1/3-turn, etc. impression cylinder). In a double or multi-sized impression cylinder, the lateral surface is known to be formed by partial jacket surfaces arranged between the cylinder channels.

As a second advantage may be stated that the cold foil material in a press nip, formed from the sheet material leading impression cylinder and the adjacent cylinder is supplied and a print start on the sheet material is performed by the sheet material adjacent the foil layer of the cold foil material with the beginning of the maximum possible printing format of the sheet material in the press nip meets in contact. Thus, already in the press nip the "start of printing", i. the transfer of the cold foil material on the sheet material (beginning of printing) take place immediately. In a previous process step, the imagewise application of adhesive to the sheet material has already been realized for this purpose, so that the film layer of the cold foil material can imagewise enter into a material-bonding connection with the adhesive in the press nip. In this case, the sheet material in the conveying direction starting with the sheet leading edge is advanced to the beginning of printing in an initial region below the lateral surface by means of holding means, in particular gripper and associated bearing surfaces, and the other, larger part of the sheet material is guided in the maximum printing format on the lateral surface of the impression cylinder.

A third advantage is that the feeding of the cold foil material in the conveying direction into the press nip can be arbitrary. For example, the cold foil material on the cylinder adjacent to the counter-pressure cylinder can be guided into the press nip in an arcuate manner in a circular arc shape in the conveying direction. Alternatively, the cold foil material may be tangent-shaped on the cylinder adjacent to the impression cylinder, i. at one point touching the cylinder, or passer-shaped, i. at a distance from the cylinder, are supplied without contact in the conveying direction in the press nip incoming.

Advantageously, markings on the cold foil material can thus be noticeably avoided and the quality of the foil coating on the respective sheet material can be noticeably improved. Furthermore, the available printing format of the sheet material can be better utilized and the amount of waste paper can be significantly reduced. By utilizing the maximum possible print format, the number of benefits per sheet material can be increased and the material consumption of the sheet material can be significantly reduced.

The invention will be explained in more detail below using an exemplary embodiment. Here are shown schematically:

1 a film transfer mechanism with two cylinders forming a press nip,

2 a press nip in the first training,

3 a press nip in second training.

A processing machine for applying cold foil material 7 on a sheet material 6 is based on the WO 2009/138335 A1 educated. According to 1 a film transfer plant is shown which is used to transport sheet material 6 in the conveying direction 3 a sheet guiding cylinder 2 , here a sheet-guiding impression cylinder 2 , having. The impression cylinder 2 adjacent is another cylinder 1 to the impression cylinder 2 placed in contact. This cylinder 1 may be a forme cylinder of a coating unit or a flexographic printing unit or a blanket cylinder of a printing unit. Preferably, the cylinder comprises 1 at least one cylinder channel 4 and is simply large (one-cylinder) and thus comprises a lateral surface 17 for guiding sheet material 6 , Alternatively, the cylinder 1 be formed double size and thus two cylinder channels 4 and thus comprises a lateral surface formed from two partial circumferential surfaces 17 for guiding the respective sheet material 6 ,

The impression cylinder 2 as well as the cylinder 1 form a press nip in the contact area 10 , For this purpose, the cylinder 1 Means for changing the axis position on, for example, end side included in side frames eccentric bearings. The surface of the cylinder 1 can wear a plastic coating, which at least in the press nip 10 with the cold foil material 7 is in contact. The plastic cover is similar to a blanket or blanket and can be on the cylinder 1 be stretched. These are in the cylinder channel 4 of the cylinder 1 provided corresponding clamping means. The plastic coating has a defined elasticity. The surface of the plastic coating may be relatively smooth or structured, for example by means of glass bead cloth, and has a low adhesion to the cold foil material 7 on. Alternatively, the plastic coating may be a high pressure plate or a recessed blanket. By means of Plastic surface becomes a clean, sharp transfer of the imaging film layer on the sheet material 6 allows.

The impression cylinder 2 points to the transport of sheet material 6 one or more holding means 5 on, which ever in a cylinder channel 4 within a lateral surface 17 the impression cylinder 2 are arranged. In the present example, the impression cylinder is 2 with two diametrically arranged cylinder channels 4 double-sized (½-turn impression cylinder) formed. Preferably, the holding means comprise 5 at least one, arranged on a gripper shaft gripper 5.1 and to the grapple 5.1 adjacent to a fixed edition 5.2 , The edition 5.2 has a support surface 5.3 on. Between the at least one gripper 5.1 and the associated bearing surface 5.3 can the sheet material 6 be transported fixed in the so-called gripper closure. In the position of the gripper closure, the at least one gripper 5.1 and the stationary associated bearing surface 5.3 within a lateral surface 17 the impression cylinder 2 arranged. The holding means are preferred 5 by a plurality of grippers spaced on the gripper shaft 5.1 with assigned conditions 5.2 and bearing surfaces 5.3 educated.

To realize a sufficient pressure, only the press nip comprise 10 forming impression cylinder 2 and cylinders 1 Means for generating the area-related force (contact pressure) on the imagewise with an adhesive 12 provided and with the cold foil material 7 operatively connected sheet material 6 , For this purpose, the cylinder 1 including the changeable axle position. The impression cylinder 2 may be an elevator (with or without pad), for example a blanket or a paint and / or paint-repellent elevator based on homopolymers such as polyvinyl fluoride (PVF) or polyvinylidene fluoride (PVDF), alternatively based on copolymers such as perfluoroethylene propylene (FEP) or Perfluoroalkoxy copolymer (PFA) or ethylene tetrafluoroethylene (ETFE) or ethylene-chlorotrifluoroethylene (E-CTFE) or fluorinated acrylates.

Through the press nip 10 is a cold foil material 7 guided. In this case, the cold foil material 7 circular arc on the cylinder 1 guided ( 2 ) or tangentially guided in the press nip 10 be encouraged. The cold foil material is preferred 7 on a film supply roll 13 received and is from this in the conveying direction, ie in the direction of press nip 10 , settled. The foil supply roll 13 may preferably be rotatably mounted in the film transfer factory. Alternatively, the film supply roll 13 Depending on the machine configuration, it may also be rotatably mounted in a forward or downstream factory adjacent to the film transfer station. Preferably, after passing through the press nip 10 the remaining, ie not on a sheet material 6 transferred cold foil material 7 on a foil collecting roll 14 be wound up. The foil collecting roll 14 may preferably be rotatably mounted in the film transfer factory. Alternatively, the film collection roll 14 also be rotatably mounted in a forward or downstream plant adjacent to the film transfer plant. Alternatively, the film supply roll 13 and the foil collecting roll 14 be laterally offset from the processing machine stationary or movable. For the purpose of guiding the cold foil material 7 The film transfer unit comprises a plurality of guide means known per se 16 , preferably guide rollers 16 , alternatively at least one leadership role 16 or other guide elements for the cold foil material 7 ,

The cold foil material 7 is at least formed from a film substrate, a fixedly arranged on the film substrate separation layer and connected to the release layer, the sheet material 6 facing arranged film layer. The latter film layer is formed by parts that are not imaging and are named here as a non-imaging film layer as well as parts that are imaging and are named here as an imaging film layer. The aforementioned cold foil material 7 is thus multi-layered, relatively thin. As a film substrate, it has a carrier layer, which is preferably thin and tear-resistant. The separating layer serves to facilitate the lifting of the imaging film layer from the film substrate. The film layer may be, for example, a metallized layer or a gloss layer or a texture layer or a colored layer or a pattern-containing layer. The cold foil material 7 is processed according to the principle of cold foil transfer. For this purpose, an imaging pattern of an adhesive substance 12 (Glue, paint, varnish) on a sheet material 6 applied. This may be in an applicator, preferably a printing unit or preferably a coating unit in each case in the conveying direction 3 in front of the press nip 10 , already done.

The film transfer unit further comprises a first radiation source or drying source 8th which in the conveying direction 3 after the press nip 10 at a defined distance to the impression cylinder 2 is arranged. The radiation / drying source is preferred 8th a UV radiation / drying source and is in the conveying direction 3 after the press nip 10 the impression cylinder 2 allocated adjacent.

In addition, in the conveying direction 3 in front of the press nip 10 additionally a second radiation source or drying source nine , in a defined distance to the impression cylinder 2 be arranged. 1 shows a radiation / drying source nine , which in the inlet gap in front of the cylinder 1 and Impression cylinder 2 formed press nip 10 is arranged and on with adhesive 12 provided sheet material 6 is directed. If necessary, one in front of the press nip 10 arranged radiation / drying source nine Means include for stimulating the crosslinking (polymerization) of the adhesive 12 and / or means for introducing a heat input to the adhesive 12 or on the sheet material 6 ,

As in WO 2009/138335 A1 sufficiently disclosed, is on the impression cylinder 2 a wrapping angle provided in the sheet material 6 and the cold foil material 7 synchronous, congruent - starting from the press nip 10 and until the beginning of a discharge gap 11 - on the impression cylinder 2 are guided.

The impression cylinder 2 adjacent radiation / drying source 8th can be essentially about the in WO 2009/138335 A1 revealed wrap angle α extend. The radiation / drying source is preferred 8th the press nip 10 subordinate adjacent. In a further embodiment, the radiation / drying source 8th with its direction of action in the press nip 10 be directed. For this purpose, between the radiation / drying source 8th and the cylinder 1 a Abschotteinrichtung be provided.

In conveying direction 3 is after the wrap angle an outlet gap 11 intended. In this outlet gap 11 becomes the remaining cold foil material that is not needed for an imaging coating 7 separated from the imaging film layer. The imaging film layer becomes when passing the outlet gap 11 as a result of the adhesive force on the sheet material 6 arranged adhesive 12 from the cold foil material 7 dissolved out and remains on the sheet material 6 , At least one deflection 15 , For example, a guide roller 15 or at least one deflection roller or other deflection contour, for example a sliding guide, is for the remaining cold foil material 7 arranged, which the web of the cold foil material 7 in the direction of the film collecting roll 14 leads. Alternatively, several pulleys 15 or another deflecting element may be formed. The deflection 15 is out of contact with the sheet material 6 (with imaging film layer) leading impression cylinder 2 , so no pressure on the sheet material 6 acts.

The 2 and 3 show inter alia the respective press nip 10 the film transfer plant for the application of cold foil material 7 on the sheet material 6 with a sheet material 6 in the conveying direction 3 leading impression cylinder 2 , Within the lateral surface 17 are the holding means 5 ; 5.1 to 5.3 arranged. Furthermore, the cylinder 1 shown by the cold foil material 7 at least formed of a film substrate, a release layer fixed on the film substrate, and a sheet material bonded to the release layer 6 associated film layer, is conveyed. As described, the cylinder points 1 a changeable axle position on and exclusively in the press nip 10 is the cold foil material 7 by means of a surface-related force on the image already with adhesive 12 Affected sheet material 6 pressed.

In conveying direction 3 is at least in the press nip 10 the cold foil material 7 , especially its film substrate, in contact with the cylinder 1 transportable. The at the impression cylinder 2 provided holding means 5 ; 5.1 to 5.3 for the sheet material 6 are each in a cylinder channel 4 the impression cylinder 2 within its lateral surface 17 arranged. In conveying direction 3 ahead is a bow leading edge 18 of the sheet material to be transported 6 by means of the holding means 5 ; 5.1 to 5.3 fixed within the lateral surface 17 arranged and a maximum print format 20 same sheet material 6 is on the lateral surface 17 arranged.

The holding means 5 ; 5.1 to 5.3 , especially the pads 5.2 with bearing surfaces 5.3 , can in a training - starting from the lateral surface 17 the impression cylinder 2 - in the conveying direction 3 in the direction of the respective associated cylinder channel 4 be arranged inclined at an angle expiring. In a further training, the requirements 5.2 with bearing surfaces 5.3 for the holding means 5 - in relation to the lateral surface 17 the impression cylinder 2 - Radially in the direction of the axis of the impression cylinder 2 inside offset within the lateral surface 17 ie lying lower, be arranged. In both trainings are the grippers 5.1 , in particular their gripper fingers, designed adapted so that during the sheet transport, the holding means 5 ; 5.1 to 5.3 , and that with the sheet leading edge 18 of the bow material 6 in the gripper closure within the respective lateral surface 17 the impression cylinder 2 are arranged. When on the outer surface 17 the impression cylinder 2 guided, the maximum print format 20 having selbigen sheet material 6 is a print start 19 in the press nip 10 arranged.

In a training can in the conveying direction 3 in front of the press nip 10 the cold foil material 7 with the cylinder 1 in a wrap angle in contact circular arc in the press nip 10 be eligible. In a further embodiment, in the conveying direction 3 in front of the press nip 10 the cold foil material 7 with the cylinder 1 tangent-shaped, ie in line contact with the cylinder 1 to be eligible. In a further embodiment, in the conveying direction 3 in front of the press nip 10 the cold foil material 7 with the cylinder 1 passantenförmig, ie in one Distance to the cylinder 1 to be eligible. If necessary, in the conveying direction 3 in front of the cylinder 1 a guide 16 , For example, as a rotatably mounted roller or roller, for guiding the cold foil material 7 be arranged ( 3 ).

The working procedure is as follows: The application of cold foil material 7 on a sheet material 6 takes place in a processing machine and comprises first an imagewise coating of the sheet material 6 with an adhesive 12 , below a press nip 10 , formed from a sheet material 6 in the conveying direction 3 leading impression cylinder 2 with within its lateral surface 17 arranged holding means 5 ; 5.1 to 5.3 and another cylinder 1 through which the cold foil material 7 at least formed of a film substrate, a release layer fixed on the film substrate, and a sheet material bonded to the release layer 6 associated film layer is promoted. It is exclusively in the press nip 10 the cold foil material 7 by means of a surface-related force of the cylinder having a variable axis position 1 on the picture with adhesive 12 Affected sheet material 6 pressed. In the press nip 10 becomes a print start 19 on the sheet material 6 Realize by the foil layer of the cold foil material 7 with the beginning of a maximum possible print format 20 of the bow material 6 meets in contact, the foil layer of the cold foil material 7 with the glue 12 pictorially enters a cohesive connection and the sheet material 6 in the conveying direction 3 with a bow leading edge 18 until the beginning of printing 19 below the lateral surface 17 by means of the holding means 5 ; 5.1 to 5.3 is fixed and the same sheet material 6 with the further, maximum print format 20 on the lateral surface 17 the impression cylinder 2 to be led.

LIST OF REFERENCE NUMBERS

1

Cylinder (blanket / blanket cylinder)

2

Impression cylinder

3

conveying direction

4

cylinder gap

5

holding means

5.1

grab

5.2

edition

5.3

bearing surface

6

sheet material

7

Cold foil material

8th

first radiation / drying source

9

second radiation / drying source

10

press nip

11

outlet gap

12

adhesive

13

Film supply roll

14

Foil composite role

15

Deflection means (deflection roller / roller)

16

Guide means (guide roller / roller)

17

lateral surface

18

Sheet leading edge

19

print start

20

maximum print format

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 2009/138335 A1 [0002, 0015, 0023, 0024]
• WO 2008/084191 A1 [0003, 0004]

Claims (8)

Method for applying cold foil material ( 7 ) on a sheet material ( 6 ) in a processing machine comprising a pictorial coating of the sheet material ( 6 ) with an adhesive ( 12 ), followed by a press nip ( 10 ), formed from a sheet material ( 6 ) in the conveying direction ( 3 ) leading impression cylinder ( 2 ) with within the lateral surface ( 17 ) holding means ( 5 ; 5.1 to 5.3 ) and another cylinder ( 1 ), through which the cold foil material ( 7 ), at least formed of a film substrate, a release layer fixed on the film substrate and a sheet material ( 6 ) is conveyed, wherein exclusively in the press nip ( 10 ) the cold foil material ( 7 ) by means of a surface-related force of the variable axis position cylinder ( 1 ) on the imagewise with adhesive ( 12 ) sheet material ( 6 ) is pressed, characterized in that in the press nip ( 10 ) a print start ( 19 ) is carried out by the film layer of the cold foil material ( 7 ) with the beginning of a maximum possible print format ( 20 ) of the sheet material ( 6 ) meets the film layer with the adhesive ( 12 ) imagewise enters into a cohesive connection, and that the sheet material ( 6 ) in the conveying direction ( 3 ) with a sheet leading edge ( 18 ) to the beginning of printing ( 19 ) below the lateral surface ( 17 ) by means of the holding means ( 5 ; 5.1 to 5.3 ) and the sheet material ( 6 ) with the maximum print format ( 20 ) on the impression cylinder ( 2 ) to be led. Film transfer plant for the application of cold foil material ( 7 ) on a sheet material ( 6 ) in a processing machine with a sheet material ( 6 ) in the conveying direction ( 3 ) leading impression cylinder ( 2 ) with within a lateral surface ( 17 ) holding means ( 5 ; 5.1 to 5.3 ) and another cylinder ( 1 ), which has a press nip ( 10 ) by which the cold foil material ( 7 ), at least formed of a film substrate, a release layer fixed on the film substrate and a sheet material ( 6 ) associated film layer is conveyed, wherein the cylinder ( 1 ) has a variable axis position and exclusively in the press nip ( 10 ) the cold foil material ( 7 ) by means of a surface-related force on the imagewise with adhesive ( 12 ) sheet material ( 6 ) is pressable, characterized in that in the conveying direction ( 3 ) the cold foil material ( 7 ) at least in the press nip ( 10 ) in contact with the cylinder ( 1 ) is transportable that at the impression cylinder ( 2 ) the holding means ( 5 ; 5.1 to 5.3 ) for the sheet material ( 6 ) in a respective cylinder channel ( 4 ) within the lateral surface ( 17 ) are arranged, and that a sheet leading edge ( 18 ) of the sheet material ( 6 ) by means of the holding means ( 5 ; 5.1 to 5.3 ) fixed within the lateral surface ( 17 ) and a maximum print format ( 20 ) of the same sheet material ( 6 ) on the lateral surface ( 17 ) is arranged. Film transfer mechanism according to claim 2, characterized in that on the lateral surface ( 17 ) of the impression cylinder ( 2 ), the maximum print format ( 20 ) having sheet material ( 6 ) the beginning of printing ( 19 ) in the press nip ( 10 ) is arranged. Film transfer mechanism according to claim 2, characterized in that in the conveying direction ( 3 ) in front of the press nip ( 10 ) the cold foil material ( 7 ) with the cylinder ( 1 ) in a loop angle in contact circular arc in the press nip ( 10 ) is eligible. Film transfer mechanism according to claim 2, characterized in that in the conveying direction ( 3 ) in front of the press nip ( 10 ) the cold foil material ( 7 ) with the cylinder ( 1 ) tangent-shaped, ie in a line contact with the cylinder ( 1 ), is eligible. Film transfer mechanism according to claim 2, characterized in that in the conveying direction ( 3 ) in front of the press nip ( 10 ) the cold foil material ( 7 ) to the cylinder ( 1 ) Passantenförmig, ie at a distance from the cylinder ( 1 ), is eligible. Film transfer mechanism according to claim 2, characterized in that the holding means ( 5 ; 5.1 to 5.3 ) at least one gripper ( 5.1 ) and the gripper ( 5.1 ) adjacent to a fixed support ( 5.2 ) include that the edition ( 5.2 ) a support surface ( 5.3 ), and that in the gripper closure the at least one gripper ( 5.1 ) within the lateral surface ( 17 ) is arranged. A film transfer mechanism according to claim 2 and any one of claims 4, 5 or 6, characterized in that the surface of the cylinder ( 1 ) carries a plastic coating.

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