CORRUGATED-BOARD MACHINE

Abstract

The invention relates to a corrugated-board machine for manufacturing corrugated board. The corrugated-board machine comprises a material-web output device for outputting a material web, an inkjet printing device disposed downstream of the material-web output device for the imprinting of at least one imprint onto the material web and an overcoating arrangement disposed downstream of the inkjet printing device for overcoating the printed material web at least in regions.

Claims

1. A corrugated-board machine for manufacturing corrugated board, comprising a) a material-web output device (31) for outputting a material web (37), b) an inkjet printing device (44) disposed downstream of the material-web output device (31) for printing at least one imprint (45) on the material web (37), and c) an overcoating arrangement, disposed downstream of the inkjet printing device (44), for overcoating the printed material web (37) at least in regions.

2. A corrugated-board machine according to claim 1, wherein the overcoating arrangement comprises a varnishing unit (48) for substantially full-faced overcoating a printed side (40) of the material web (37) with at least one overcoating layer (49).

3. A corrugated-board machine according to claim 2, wherein the varnishing unit (48) comprises at least one overcoat-application roller (50) for applying the at least one overcoating layer (49) on the printed side (40) of the material web (37).

4. A corrugated-board machine according to claim 2, wherein the varnishing unit (48) comprises at least one dosage element (51) for dosed application of the at least one overcoating layer (49) onto the material web (37).

5. A corrugated-board machine according to claim 2, wherein the varnishing unit (48) comprises a varnish-application control device (48a), which controls an application of the at least one overcoating layer (49) onto the printed side (40) of the material web (37) via at least one of the group comprising a detected moisture and a layer thickness of the at least one overcoating layer (49).

6. A corrugated-board machine according to claim 1, wherein the overcoating arrangement comprises an inkjet-varnishing device (54) for inkjet-varnishing the printed material web (37) in regions with at least one inkjet-varnish region (55).

7. A corrugated-board machine according to claim 6, wherein the at least one inkjet-varnish region (55) is smaller in its area on the printed material web (37) than at least one overcoating layer (49).

8. A corrugated-board machine according to claim 6, wherein the at least one inkjet-varnish region (55) covers the at least one imprint (45) at least in regions in order to increase its gloss effect at least in regions.

9. A corrugated-board machine according to claim 2, wherein the at least one inkjet-varnish region (55) is characterized by a higher degree of gloss by comparison with the at least one overcoating layer (49).

10. A corrugated-board machine according to claim 6, comprising an inkjet-varnishing control device (54a) for the position control of the at least one inkjet-varnish region (55) on the printed material web (37)

11. A corrugated-board machine according to claim 10, wherein the positioning control takes place on the basis of markings (72, 74) of the printed material web (37).

12. A corrugated-board machine according to claim 10, comprising a marking-reading device (53) for the reading of markings (72, 74) arranged on the printed material web (37), wherein the inkjet-varnishing control device (54a) receives marking-position signals from the marking-reading device (53).

13. A corrugated-board machine according to claim 6, wherein a matching of the at least one inkjet-varnish region (55) to the at least one imprint (45) takes place.

14. Corrugated-board machine according to claim 2, wherein the inkjet-varnishing device (54) is disposed downstream of the varnishing unit (48) in conveying direction (38) of the material web (37).

15. A corrugated-board machine according to claim 1, comprising a control in a flow time of at least one of the group comprising the at least one imprint (45) and of the overcoating (49, 55).

16. A corrugated-board machine according to claim 15, wherein the flow time is controllable through pre-drying.

17. A corrugated-board machine according to claim 1, wherein an inkjet print drying device (46) for drying the printed material web (37) is disposed downstream of the inkjet printing device (44).

18. A corrugated-board machine according to claim 1, wherein a hot-pressing device (64) for connecting the printed and overcoated material web (37) to at least one further material web (22) is disposed downstream of the overcoating arrangement.

19. A corrugated-board machine according to claim 18, wherein the at least one further material web (22) is at least one corrugated-board web.

20. A corrugated-board machine according to claim 18, wherein at least one moistening unit (58) is arranged between the overcoating arrangement and the hot-pressing device (64).

21. A method for manufacturing corrugated board, comprising the following steps: output of a material web (37) by means of a material-web output device (31), imprinting of at least one imprint (45) onto the material web (37) output by the material-web output device (31) by means of an inkjet printing device (44), and overcoating the printed material web (37) at least in regions by means of an overcoating arrangement.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0035] FIG. 1 shows a schematic view of a first upstream part of a corrugated-board machine according to the invention;

[0036] FIG. 2 shows an enlarged view of the region marked in FIG. 1, which shows, in particular, the inkjet printing device and the overcoating arrangement;

[0037] FIG. 3 shows a simplified section which visualizes the printed and overcoated material web;

[0038] FIG. 4 shows a diagrammatic view of a first upstream part of a corrugated-board machine according to the invention according to a second embodiment; and

[0039] FIG. 5 shows a plan view of a section of a material web.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0040] Initially, with reference to FIG. 1, a corrugated-board machine comprises an arrangement 1 for manufacturing an endless corrugated-board web laminated on one side.

[0041] A first splicing device 2 and a second splicing device 3 are arranged upstream of the arrangement 1 for manufacturing an endless corrugated-board web laminated on one side.

[0042] The first splicing device 2 comprises a first unrolling unit 6 for the unrolling of an open-ended first material web 4 from a first material-web roller 5 and a second unrolling unit 8 for the unrolling of an open-ended second material web from a second material-web roller 7. The open-ended first material web 4 and second material web are connected to one another in order to provide an endless first material web 9 by means of a connecting and cutting unit of the first splicing device 2 which is not illustrated.

[0043] The second splicing device 3 is constituted to correspond to the first splicing device 2. This comprises a third unrolling unit 12 for the unrolling of an open-ended third material web 10 from a third material-web roller 11 and a fourth unrolling unit 14 for the unrolling of an open-ended second material web from a fourth material-web roller 13. The open-ended third material web 10 and fourth material web are connected to one another in order to provide an endless second material web 15 by means of a connecting and cutting unit of the second splicing device 3 which is not illustrated.

[0044] The endless first material web 9 is supplied via a heating roller 16 and a first deflection roller 17 to the arrangement 1 for manufacturing an endless corrugated-board web laminated on one side, while the endless second material web 15 is supplied via a second deflection roller 18 to the arrangement 1 for manufacturing an endless corrugated-board web laminated on one side.

[0045] The arrangement 1 for manufacturing an endless corrugated-board web laminated on one side comprises, for the production of an endless corrugated web 19 comprising a corrugation from the endless second material web 15, a first corrugating roller 20 mounted in a rotatable manner and a second corrugating roller 21 mounted in a rotatable manner. The corrugating rollers 20, 21 form a roller gap for the passage and corrugation of the endless second material web 15, wherein axes of rotation of the two corrugating rollers 20, 21 extend parallel to one another. Together, the corrugating rollers 20, 21 form a corrugating unit.

[0046] For the connection of the endless corrugated web 19 to the first endless material web 9 to form an endless corrugated-board web 22 laminated on one side, the arrangement 1 for manufacturing an endless corrugated-board web laminated on one side comprises a glue-application unit 23, which comprises a glue-dosage roller 24, a glue container 25 and a glue-application roller 26. For the passage and gluing of the endless corrugated web 19, the glue-application roller 26 forms a gluing gap with the first corrugating roller 20. The glue disposed in the glue container 25 is applied via the glue-application roller 26 to tips of the corrugation of the endless corrugated web 19. The glue-dosage roller 24 is disposed in contact with the glue-application roller 26 and serves for the formation of a uniform glue layer on the glue application roller 26.

[0047] The endless first material web 9 is then fitted together with the endless corrugated web 19 provided with glue from the glue container 25 in the arrangement 1 for manufacturing an endless corrugated-board web 22 laminated on one side, thereby forming a corrugated-board web laminated on one side.

[0048] For the pressing of the endless first material web 9 against the endless corrugated web 19 provided with glue, which, in turn, is in contact in regions with the first corrugating roller 20, the arrangement 1 for manufacturing an endless corrugated-board web has a pressing device 27. The pressing device 27 is favorably constituted as a pressing-belt module and is arranged above the first corrugating roller 20. The pressing module 27 has two deflection rollers 28 and an endless pressing belt 29, which is guided around the deflection rollers 28. The first corrugating roller 20 engages in a space present between the deflection rollers 28 in regions, so that the pressing belt 29 is deflected by the first corrugating roller 20. The pressing belt 29 presses against the endless first material web 9, which is pressed in turn against the endless corrugated web 19 provided with glue, in contact with the first corrugating roller 20.

[0049] For the intermediate storage and buffering of the endless corrugated-board web 22 laminated on one side, this is supplied to a storage unit 30, where the latter forms loops or bows.

[0050] Furthermore, the corrugated-board machine as a third splicing device 31, which is constituted corresponding to the first or respectively second splicing device 2, 3. The third splicing device 31 comprises a fifth unrolling unit 34 for the unrolling of an open-ended fifth material web 32 from a fifth material-web roller 33, and a sixth unrolling unit 36 for the unrolling of an open-ended sixth material web from a sixth material-web roller 35. The open-ended fifth material web 32 and sixth material web are connected to one another in order to provide an endless third material web 37 by means of a connecting and cutting unit of the third splicing device 31, which is not illustrated. The endless third material web 37 forms an outer laminated web on the finished corrugated-board web to be produced.

[0051] The endless third material web 37 is conveyed downstream to the third splicing device 31 in a conveying direction 38.

[0052] Downstream of the third splicing device 31, a pre-coating application device 39 is associated with the endless third material web 37, which applies a two-dimensional pre-coating 41 onto the outer side 40 of the endless third material web 37. In particular, the two-dimensional pre-coating 41 substantially covers the endless third material web 37 over the full surface of its outer side 40.

[0053] Downstream of the pre-coating application device 39, a pre-coating drying device 42, which dries the endless third material web 37 provided on the outside with the pre-coating 41 or respectively the pre-coating 41, is associated with the endless third material web 37.

[0054] Downstream of the pre-coating drying device 42, a cleaning device 43, which cleans the endless third material web 37, which carries the dried pre-coating 41, at least on the outside, is associated with the endless third material web 37.

[0055] Downstream of the cleaning device 43, an inkjet printing device 44, which imprints at least one imprint 45 onto the endless third material web 37 or respectively onto the dried pre-coating 41, is associated with the endless third material web 37. The pre-coating 41 is accordingly disposed between the at least one imprint 45 and the third material web 37. The at least one imprint 45 is favorably a water-based color imprint. In its area, it is favorably smaller than the pre-coating 41.

[0056] Downstream of the inkjet printing device 44, an inkjet print drying device 46 which dries the printed endless third material web 37 or respectively its at least one imprint 45, is associated with the endless third material web 37.

[0057] Downstream of the inkjet print drying device 46, an imprint checking unit 47 which checks the at least one imprint 45 printed onto the endless third material web 37, is associated with the endless third material web 37.

[0058] Downstream of the imprint checking unit 47, a varnishing unit 48 for the full-surface application of at least one transparent overcoating layer 49 to the outside of the endless third material web 37 is associated with the endless third material web 37. The at least one imprint 45 is accordingly disposed between the at least one overcoating layer 49 and the pre-coating 41. The at least one overcoating layer 49 covers the full surface of the at least one imprint 45 and is in direct contact with the latter. Laterally alongside the at least one in print 45, the at least one overcoating layer 49 is in direct contact with the pre-coating 41. The at least one overcoating layer 49 is formed by matt varnish, which is based on water and also designated as water varnish or respectively dispersion varnish.

[0059] The varnishing unit 48 in the exemplary embodiment described comprises an overcoat-application roller 50, which faces towards the outer side 40 of the endless third material web 37. The varnishing unit 48 further comprises a standing overcoat dosage roller 51, which is preferably constituted as comma bar or respectively comma-bar, and is presented to the overcoat-application roller 50 at a precise angle in order to ensure a uniform overcoat film on the latter. A fluid bath or respectively varnish bath is disposed, in one illustrated variant, on an upper side between the overcoat-application roller 50 and the overcoat-dosage roller 51 in a space closed off at the bottom apart from a small gap. The varnish transfer from the application roller 50 and the material web 37 takes place here, for example, in so-called synchronization. Other embodiments of the dosage method are possible as an alternative.

[0060] Downstream of the varnishing unit 48, a material-web inspection device 52, which inspects the endless third material web 37 for faults especially on its outer side 40, is associated with the endless third material web 37. This material-web inspection device 52 checks especially the flatness of the third material web 37. With regard to details and function of the material-web inspection device 52, reference is made, for example, to WO 2014/128115 A1.

[0061] Downstream of the material-web inspection device 52, a marking-reading device 53, which is, in particular, capable of reading or respectively detecting external markings 72, 74 (FIG. 5) of the endless third material web 37, is associated with the endless third material web 37. The marking-reading device 53 favorably operates in a contactless manner.

[0062] Downstream of the marking-reading device 53, an inkjet-varnishing device 54, which applies at least one spatially limited inkjet-varnish region 55 to the outside of the endless third material web 37, is associated with the endless third material web 37. The at least one overcoating layer 49 is accordingly disposed between the at least one inkjet-varnish region 55 and the pre-coating 41. The at least one inkjet-varnish region 55 favorably covers the at least one imprint 45 at least in regions, for example, along its contours or over the full surface.

[0063] This arrangement of the at least one inkjet-varnish region 55 can favorably be achieved by the marking-reading device 53. The markings 72, 74 detected by the marking-reading device 53 provide information about the arrangement of the at least one imprint 45 and/or the position of the at least one inkjet varnish region 55 to be produced. The inkjet-varnishing device 54 has a corresponding inkjet-varnishing control device 54a for this purpose.

[0064] Downstream of the inkjet-varnishing device 54, an inkjet-varnish drying device 56 for drying the endless third material web 37 or respectively the at least one inkjet-varnish region 55, is associated with the endless third material web 37. The drying is implemented here thermally by infrared radiation and/or by hot air. A combination of both heat sources is particularly advantageous.

[0065] Downstream of the inkjet varnish drying device 56, a flash unit 57 and gloss-measuring unit 57a, which measures an outside gloss of the endless third material web 37 or respectively of the at least one inkjet-varnish region 55, is associated with the endless third material web 37. The flash unit 57 allows control of an overprinting accuracy through directed reflection of the inkjet varnish by reading in markings 72, 74. The markings 72, 74 preferably comprise at least one dash, circle, semicircle, registration marks or at least one similar, simple geometric shape. The corrections required on this basis, can be implemented by the inkjet-varnishing device 54, which then receives corresponding signals.

[0066] Downstream of the flash unit 57 and gloss-measuring unit 57a, a moistening unit 58, which supplies water, favorably in the form of a steam spray, onto the endless third material web 37, opposite to the outer side 40, is associated with the endless third material web 37. A flat position and a homogenous moisture profile of the third material web 37 can be guaranteed as a result. It is advantageous if the moistening unit 58 comprises a zone circuit and can be controlled by the measured value of a downstream, traversing moisture sensor.

[0067] A pre-heating device 59, which comprises two pre-heating rollers 60 arranged one above the other is disposed downstream of the storage unit 30 and the moistening unit 58. The corrugated-board web 22 laminated on one side and the endless third printed, dried and overcoated material web 37, which both partially surround the respective pre-heating roller 60, are supplied to the pre-heating device 59. The endless third material web 37 runs in the pre-heating device 59 below the corrugated-board web 22 laminated on one side, wherein the outer side 40 of the endless third material web 37 faces downwards there or respectively faces away from the corrugated-board web 22 laminated on one side.

[0068] A gluing unit 61 with a gluing roller 62, which is partially immersed in a glue bath, is arranged downstream of the pre-heating device 59. The corrugated-board web 22 laminated on one side is disposed in contact with the gluing roller 62 and is accordingly provided with glue from the glue bath. A dosage roller 63 is in contact with the periphery of the gluing roller 62 in order to form a uniform glue film on the gluing roller 62. The endless third material web 37 runs in the gluing unit 61 below the corrugated-board web 22 laminated on one side, wherein the outer side of the endless third material web 37 faces downwards there or respectively faces away from the corrugated-board web 22 laminated on one side. A hot-pressing device 64 which comprises a horizontally extending heated table 65 with heating elements is arranged downstream of the gluing unit 61. A pressing belt 67 guided via guide rollers 66 is arranged adjacent to the heated table 65. Between the pressing belt 67 and the heated table 65, a pressing gap is formed, through which the glued corrugated-board web 22 laminated on one side and the endless third, printed and overcoated material web 37 are guided. The endless third material web 37 runs in the hot-pressing device 64 below the corrugated-board web 22 laminated on one side, wherein the outer side 40 of the endless third material web 37 faces downwards there or respectively faces away from the corrugated-board web 22 laminated on one side.

[0069] An endless corrugated-board web 68 laminated on both sides, which is printed on the outer side, is present downstream of the hot pressing device 64. According to one alternative embodiment, more than three material webs are present.

[0070] A longitudinal cutting/creasing device (not illustrated) for the longitudinal cutting and creasing of the corrugated-board web 68, a transverse cutting device for the transverse cutting of the corrugated-board web 68, distributing guide (not illustrated) for subdividing the corrugated-board sub-webs produced from the corrugated-board web 68 into different levels, transverse cutting devices (not illustrated) for the transverse cutting of the corrugated-board sub-webs into corrugated-board sheets and stacking devices (not illustrated) for the stacking of the corrugated-board sheets are arranged downstream of the hot-pressing device 64.

[0071] The at least one imprint 45 produced is visually extremely attractive. It is characterized, in particular, by the impression of an extremely high-quality gloss. Furthermore, this is extremely abrasion-resistant, because it is protected.

[0072] The following is a description, with reference to FIGS. 4, 5, of a second embodiment. Contrary to the previous embodiment, to the description of which is made reference explicitly, a material web pre-heating device 69 is arranged upstream of the overcoating arrangement, said material web pre-heating device 69 being in particular arranged upstream of the varnishing unit 48 and, preferably, adjacent thereto. The material web pre-heating device 69 favorably comprises a material web pre-heating roller 70 about which the endless third material web 37 is guided. It is expedient if a wrap angle of the endless third material web 37 about the material web pre-heating roller 70 is adjustable to adapt the pre-heating of the endless third material web 37.

[0073] Downstream of the varnishing unit 48, a material web pre-drying unit 71 is provided, said material web pre-drying unit 71 being associated to the endless third material web 37, to expose the endless third material web 37 to a pre-drying procedure after the application of the at least one transparent overcoating layer 49. The material web pre-drying device 71 is favorably arranged upstream of the material web inspection device 52 to ensure that the endless third material web 37 has dried at least partly upon reaching the material web inspection device 52.

[0074] Favorably, the marking-reading device 47 detects the cross and longitudinal markings 72, 74 applied to the endless third material web 37. The corresponding distance information of the cross markings 72 relative to each other and of the longitudinal markings 74 relative to each other is transmitted, via a signal line 73, to the inkjet-varnishing control device 54a to adapt the size of the at least one inkjet region to the at least one imprint. Alternatively or in addition thereto, cross cutting markings on the endless third material web 37 and their distance to each other are detected. Alternatively, the size of the at least one imprint is detected and compared with an artwork to adapt the size of the at least one inkjet region to the at least one imprint. As a function thereof, the inkjet varnishing device 54 is actuated accordingly, taking into consideration the size adjustment of the inkjet varnishing device 54.

[0075] It is conceivable to combine the embodiments with each other.