EP3147126B1 - Corrugated cardboard assembly - Google Patents

Description

The invention relates to a corrugated board plant according to the preamble of claim 1 and a method for producing corrugated board. Printed corrugated board webs and corrugated board plants for their production are well known in the art through public prior use.

Water-based inkjet overprints generally have the disadvantage of being dull, due to their diffuse light reflection. Matt coatings in this sense provide layer thickness-dependent and substrate-dependent gloss point values of between 10 and 50 with a 60 ° measurement geometry in accordance with ASTM D 523. Even with pre-treatment of such imprinted corrugated board webs, it is hardly possible to give them a visually appealing gloss. Water-based inkjet printing also has the disadvantage that they are not resistant to abrasion, which can lead to impairment of the inkjet printing, for example in the production of corrugated board web.

On the other hand, standard dispersion varnishes have the disadvantage that they are only poorly overprintable and glue / adhesive sticks only poorly to them. This can lead to problems in terms of printability and in folding or gluing machines in corrugated board finishing in terms of adhesiveness when necessary subsequent encodings in packaging lines.

The GB 2 493 208 A discloses a corrugating machine having a digital printing device capable of printing resulting sheets at least partially over the width thereof. Finishing coatings can also be applied.

The US 2012/0139984 A1 is concerned with inkjet printing processes in which digital data is received for printing with an inkjet printing device using a coverage area map. The coverage area map identifies areas of the image to be printed that have different coverage areas densities. First inkjet injectors are actuated to form an image on an image receiving medium. Second inkjet injectors are actuated to eject clear ink with selected halftone levels. The second inkjet injectors eject different amounts of the clear ink onto the different areas identified by the coverage area map.

From the US 2014/0285558 A1 For example, a method of adding a gloss control table for printing an image is known. A printing device for this purpose comprises a first dispensing head for dispensing color ink and a second dispensing head for dispensing clear ink.

The US 2004/0182503 A1 discloses a corrugating machine in which webs are digitally printed before being cut into corrugated sheets.

The invention has for its object to provide a corrugated plant, which overcomes the disadvantages mentioned above. In particular, a corrugated board plant is to be created, which allows an extremely economical production of corrugated board and is able to visually particularly create attractive corrugated board. In particular, the corrugated cardboard produced should also be particularly easy to process and have a high gloss effect. A corresponding method for the production of corrugated cardboard should also be supplied.

This object is achieved by the features specified in the independent claims 1 and 8 features. The core of the invention is that the material web is printed by means of an inkjet printing device and the printed material web or the at least one print produced is at least partially painted over. The overpainting of the at least one print or the printed image is particularly well protected. An impairment caused by subsequent processing is thus essentially excludable.

Such a material web or corrugated cardboard is visually very appealing. For example, particularly good contrasts, in particular matt-gloss contrasts, can be achieved on the printed material web.

The applicable with the coating unit, at least one overcoat layer is conveniently formed by matt lacquer. The at least one overcoat layer allows extremely good and simple further processing of the web or corrugated board. In particular, the at least one overcoat layer can be printed at least in one color. Furthermore, the at least one overcoat layer provides extremely high adhesion in order to ensure adhesion to components of corrugated cardboard sheets, in particular tabs. The at least one overcoat layer can be produced inexpensively. It conveniently has a substantially uniform thickness. Conveniently, an application width of the coating unit is customizable. It is advantageous if also the amount of paint to be applied is customizable. This is special achievable with the described embodiments of the metering elements in dependent claim 2.

The inkjet coating device is conveniently capable of applying glossy ink in regions to the printed web for forming the at least one inkjet paint area. The glossy ink is preferably transparent. It conveniently contains latex or is based on latex or aqueous polymer dispersions and has a suitably lower viscosity than the matt lacquer. The at least one Inkjetlackbereich is characterized in particular by a higher gloss level in comparison to the at least one overcoat layer. The highlights are in the at least one Inkjetlackbereich between 50 to 80 in a 60 ° measurement geometry according to ASTM D 523 before. By virtue of the at least one overcoat layer, less volume, in particular significantly less, of glossy ink is necessary in order to achieve these highlights than when the gloss ink is applied to a printing area without an overcoat layer. The process is therefore very economical due to the high-priced gloss ink. The at least one Inkjetlackbereich is conveniently smaller in its area on the printed material web, more preferably substantially smaller than the at least one overcoat layer. It is advantageous if at least one area on the painted-on printed material web remains free of the at least one inkjet paint area for later adhesive bonding to at least one material web or corrugated cardboard constituent. The application of the gloss ink to form the at least one Inkjetlackbereichs on the at least one overcoat layer is ideally carried out in a wet-on-wet process, which is characterized in that no or at least no complete drying of the at least one overcoat layer and the distance to the order the glossy ink is desirably short, preferably less than 10 meters, ideally less than 5 meters, is. To ensure a short flow time and sharp-edged gloss contours of the inkjet paint, the distance from application of the inkjet paint to drying is short, in particular less than 10 meters, in particular less than 5 meters.

The printing and / or repainting of the material web / takes place suitably inline in the corrugated board plant. It is advantageous if the material web is conveyed during its printing and / or topcoating.

It is advantageous if the material dispensing device comprises at least one web roll. Conveniently, the material dispensing device is designed as a splicing device, so that the material web is endless. The corrugating machine preferably also includes other material dispensers for dispensing additional webs to form the corrugated board.

The inkjet printing apparatus is in particular capable of ejecting water-based ink for printing the web of material. It is advantageous if the inkjet printing device is designed to produce at least one water-based color imprint on the material web. The ink system is preferably based on purely thermal curing or a hybrid process, in which sense a UV curing takes place after a thermal pretreatment.

The at least one print includes, for example, at least one letter, one digit, another character, a graphic and / or a photo. The at least one print conveniently covers at least regionally one side of the material web, which is visible from the outside in the finished corrugated board or web.

It is advantageous if the overcoating arrangement is capable of applying at least one, more preferably a plurality of overcoat layer (s) to the printed material web.

The printed and overcoated material web is part of a corrugated web, which advantageously comprises a total of at least two, more preferably three, five or seven, material webs. The printed and over-coated material web preferably forms an outer laminating web in the finished corrugated cardboard web.

The inkjet coating control device advantageously allows alignment of the at least one inkjet coating area after the at least one print. In particular, the at least one print and the at least one inkjet paint area are arranged one above the other or cover each other. Another orientation is possible in particular. Conveniently, the material web to be overcoated has marks for position control of the at least one inkjet paint area. The marks are for example printed on the material web and / or formed by cuts. Conveniently, these are brands that are also used for the format cut to a cross-cutting device.

It is advantageous if a flash unit with lacquer monitoring for setting an overprint accuracy of the at least one inkjet lacquer area with respect to the at least one print and / or a gloss measurement unit for measuring the gloss of the overcoated corrugated cardboard web is present downstream of the inkjet coating device / are. For example, the paint monitor includes at least one over-resist camera, while the gloss-measuring unit has, for example, at least one gloss-measurement sensor. Conveniently, the paint control and / or the gloss measurement unit are traversing systems.

There is a brand reader available. Preferably, this is a contrast sensor. It is advantageous if the tag reading device is located upstream or downstream of the inkjet coating device. For example, the brands make it possible to achieve scaling on the paint subject for the purpose of dimensional uniformity and / or the position correction of the paint image. In order to determine the dimension of the at least one print, in particular the distance from successive marks is used.

The terms "downstream," "upstream," "upstream," "downstream," or the like, as used herein, generally refer to the direction of conveyance of the particular web. This applies analogously to similar terms.

Further advantageous embodiments of the invention are specified in the subclaims.

It is advantageous if according to the dependent claim 2, the coating unit comprises at least one over-coat applicator roll for applying the at least one overcoat layer on the printed side of the web and conveniently at least one metering for metered application of at least one overcoat layer on the web. This embodiment allows a very economical and uniform application of the at least one overcoat layer on the printed material web.

Conveniently, the at least one over-coating applicator roll is smooth. It is advantageous if the at least one over-coating application roller is assigned at least one over-coating metering roller for the metered application of the overcoat to the printed material web. This embodiment is particularly suitable for high-viscosity paints. For low-viscosity paints are particularly suitable coating units, which may comprise at least one anilox roll or at least one other metering element, such as a chamber doctor blade, Druckkammerakel and several paint transfer rollers, blankets or Sleevewalzen. The web to be coated is preferably in all embodiments of the coating unit, conveniently wrapped around a rubberized roller to which at least one over-coating applicator roller defined. When using anilox rollers for metering the overcoat layer, for economic reasons, this anilox roll can at the same time have the function of the overcoat applicator roll, that is to say transfer the overcoat directly onto the paper. It is advantageous if the preferably rubberized roller for advancing the material web to the applicator roll is movable in order to interrupt the application of the overcoat layer on the moving material web as needed in a job change quickly as well as to be able to continue.

The embodiment according to the dependent claim 3 leads to an overcoat, which is visually particularly appealing and extremely economical to produce. For detecting the moisture and / or the layer thickness of the at least one overcoat layer, the printed material web provided with the at least one overcoat layer is advantageously at least one detection device, such as sensor device or camera device, assigned. According to the dependent claim 5, the inkjet coating device is arranged downstream of the coating unit. The at least one overcoat layer is conveniently arranged between the one inkjet paint area and the printed material web.

It is useful if the at least one Inkjetlackbereich according to the dependent claim 10 at least partially covers the at least one print. Thus, the at least one print at least partially an increased gloss effect available, which is visually appealing and interesting. Such a corrugated board has a very high quality. The punctual gloss level is also very easy to adjust. In particular, partial Spotlackierungen, so-called drip-off effects, or gloss gradients are easy to implement. Shiny contours are possible, for example, independently of structures of the at least one imprint.

It is advantageous if the inkjet control device for adaptation according to the dependent claim 12 transmits scaling / size values to the inkjet coating device. In particular, a size of the at least one inkjet lacquer area can be adapted to the at least one print on. Conveniently, the inkjet coating control device receives corresponding information based on distance measurements, in particular along and / or across the material web, of marks on the material web. These measurements can be carried out for example by a sensor and / or camera device. Conveniently, these measurements are made by a print inspection unit.

The embodiment according to the dependent claim 13 leads to corrugated cardboard, which is particularly high quality.

The predrying (pinning) according to the dependent claim 14 is conveniently carried out by at least one corresponding predrying device.

It is expedient if the inkjet printing device is preceded by a precoating application device for applying a precoat to the material web to be printed, wherein preferably the precoat application device is followed by a precoat drying device for drying the precoated material web. This embodiment results in a material web which is particularly easy to print on and / or overpaintable. Such a corrugated board is visually very appealing.

The same applies essentially to a corrugated board system with a corona pretreatment device for pretreating the material web to be printed, which is arranged upstream of the inkjet printing device. Surface energy of the material web can be controlled by means of corona pretreatment and / or pre-tempering.

It is expedient if the overpainting arrangement is followed by a preheating device for preheating the printed and overpainted material web and at least one further material web, in particular at least one corrugated web web. The preheating device advantageously comprises preheating rollers which are in contact with the material webs to be connected for heating the same.

The overpainting arrangement is expediently arranged downstream of a gluing unit for applying glue to at least one further material web, in particular a corrugated board web, to be connected to the printed and overpainted material web.

It is advantageous if a material web preheating device for preheating the material web of the overpainting arrangement is arranged upstream. A material web (pre) drying device for (pre) drying the coated material web downstream of the coating unit, preferably between the coating unit and the inkjet coating apparatus, is favorably arranged. The features of the dependent claims 2 to 7 may also be the subject of independent claim 8.

Fig. 1

eine schematische Ansicht eines ersten stromaufwärtigen Teils einer erfindungsgemäßen Wellpappe-Anlage,

Fig. 2

eine vergrößerte Ansicht des in Fig. 1 gekennzeichneten Bereichs, der insbesondere die Inkjet-Druckvorrichtung und die Überlackierungsanordnung zeigt,

Fig. 3

einen vereinfachten Schnitt, der die bedruckte und überlackierte Materialbahn veranschaulicht,

Fig. 4

eine schematische Ansicht eines ersten stromaufwärtigen Teils einer erfindungsgemäßen Wellpappe-Anlage gemäß einer zweiten Ausführungsform, und

Fig. 5

eine Draufsicht auf einen Ausschnitt aus einer Materialbahn.

Hereinafter, preferred embodiments of the invention will be described by way of example with reference to the accompanying drawings. Showing:

Fig. 1

a schematic view of a first upstream part of a corrugated board plant according to the invention,

Fig. 2

an enlarged view of the in Fig. 1 marked area, particularly showing the inkjet printing device and the overcoating arrangement,

Fig. 3

a simplified section illustrating the printed and overpainted web,

Fig. 4

a schematic view of a first upstream part of a corrugated board according to the invention according to a second embodiment, and

Fig. 5

a plan view of a section of a material web.

Referring first to Fig. 1 For example, a corrugated board installation comprises an arrangement 1 for producing a single-faced, endless corrugated board web.

The arrangement 1 for producing a single-sided, endless corrugated cardboard web are preceded by a first splicing device 2 and a second splicing device 3.

The first splicing device 2 comprises a first unwinding unit 6 for unrolling a finite first web of material 4 from a first web reel 5 and a second unwinding unit 8 for unrolling a finite second web of material from a second web reel 7. The finite first web 4 and second web are used to provide one endless first material web 9 by means of a not shown connecting and cutting unit of the first splicing device 2 connected to each other.

The second splicing device 3 is formed corresponding to the first splicing device 2. This comprises for rolling a finite third material web 10 of a third web roll 11, a third unwinding unit 12 and for unrolling a finite fourth material web from a fourth material web roll 13, a fourth unwinding unit 14. The finite third material web 10 and fourth material web are connected to each other for providing an endless second material web 15 by means of a connecting and cutting unit of the second splicing device 3, not shown.

The endless first material web 9 is supplied via a heating roller 16 and a first guide roller 17 of the arrangement 1 for producing a single-faced, endless corrugated web, while the endless second material web 15 via a second guide roller 18 of the arrangement 1 for producing a one-sided laminated endless corrugated web is supplied.

The arrangement 1 for producing a single-faced, endless corrugated web includes for generating a corrugated, endless corrugated web 19 from the endless second web 15, a rotatably mounted first corrugating roll 20 and a rotatably mounted second corrugating roll 21. The corrugating rolls 20, 21 form for performing and corrugations of the endless second material web 15 from a nip, wherein axes of rotation of the two corrugating rolls 20, 21 parallel to each other. The corrugating rolls 20, 21 together form a corrugation device.

To connect the endless corrugated web 19 with the first endless web 9 to a single-faced, endless corrugated web 22, the arrangement 1 for producing a single-faced, endless corrugated web has a glue applicator 23, which comprises a glue metering roller 24, a glue container 25 and a glue applicator roll 26 , For performing and gluing the endless corrugated web 19, the glue application roller 26 forms a gluing gap with the first corrugating roller 20 out. The glue 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 metering roller 24 bears against the glue application roller 26 and serves to form a uniform glue layer on the glue application roller 26.

The endless first web of material 9 is then joined together with the endless corrugated web 19 provided with glue from the glue container 25 in the arrangement 1 for producing a single-faced, continuous corrugated web to form the corrugated web 22 laminated on one side.

For pressing the endless first web 9 against the provided with glue endless corrugated web 19, which in turn rests partially on the first corrugating roll 20, the arrangement 1 for producing a one-sided laminated, endless corrugated web has a pressing 27. The pressing 27 is conveniently designed as Anpressbandmodul and is located above the first corrugating roll 20. The Anpressbandmodul 27 has two guide rollers 28 and an endless pressure belt 29, which is guided around the guide rollers 28. The first corrugating roller 20 engages in a space present between the guide rollers 28 in regions, whereby the pressure belt 29 is deflected by the first corrugating roller 20. The pressing belt 29 presses against the endless first material web 9, which in turn is pressed against the provided with glue, applied to the first corrugating roller 20 endless corrugated web 19.

For temporarily storing and buffering the single-faced, endless corrugated cardboard web 22, it is fed to a storage device 30, where it forms loops or loops.

Further, the corrugating machine has a third splicing device 31 formed in correspondence with the first and second splicing devices 2, 3, respectively. The third splicing device 31 comprises a fifth unwinding unit 34 for unrolling a finite fifth material web 32 from a fifth web roll 33 and a sixth unwinding unit 36 for unrolling a finite sixth material web from a sixth web roll 35. The last fifth material web 32 and sixth material web are used to provide a endless third material web 37 by means of a connecting and cutting unit, not shown, of the third splicing device 31 connected to each other. The endless third material web 37 forms an outer laminating web in the finished corrugated cardboard web to be produced.

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

Downstream of the third splicing device 31, the endless third material web 37 is assigned a precoating application device 39, which applies a planar precoat 41 to an outer side 40 of the endless third material web 37. The areal pre-coating 41 covers the endless third material web 37 on its outer side 40, in particular substantially over the entire area.

Downstream of the pre-coat applicator 39, the endless third web of material 37 is associated with a precoat drier 42 which dries the endless third web of material 37 or precoat 41 provided on the outside with the precoat 41.

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

Downstream of the cleaning device 43, the endless third material web 37 is assigned an inkjet printing device 44 which prints on the outside on the endless third material web 37 or on the dried precoat 41 at least one imprint 45. The pre-coating 41 is thus located between the at least one imprint 45 and the third material web 37. The at least one imprint 45 is conveniently a water-based color imprint. It is conveniently smaller in area than the precoat 41.

Downstream of the inkjet printing device 44, the endless third material web 37 is assigned an inkjet printing drying device 46 which dries the printed endless third material web 37 or its at least one print 45.

Downstream of the inkjet printing drying device 46, the endless third material web 37 is assigned an imprint checking unit 47, which checks the at least one imprint 45 printed on the endless third material web 37.

Downstream of the imprint test unit 47, the endless third material web 37 is assigned a coating unit 48 for the full-surface application of at least one transparent overcoat layer 49 on the outside of the endless third material web 37. The at least one imprint 45 is thus located between the at least one overcoat layer 49 and the precoating 41. The at least one overcoat layer 49 covers the at least one overprint 45 over the entire area and is directly adjacent thereto. Laterally adjacent to the at least one imprint 45, the at least one overcoat layer 49 is directly adjacent to the precoat 41. The at least one overcoat layer 49 is formed by matt lacquer, which is based on water and is also referred to as water-based paint or dispersion lacquer.

In the exemplary embodiment described, the coating unit 48 comprises an over-coating applicator roll 50, which faces the outer side 40 of the endless third material web 37. The coating unit 48 also includes a standing over-coating metering roller 51, which is preferably designed as a "Comma-bar" or Kommabar and is supplied to the over-coating applicator roller 50 angle to ensure that on this for a uniform overcoat film. A fluid bath or lacquer bath is located in a visualized variant on an upper side between the over-coating applicator roller 50 and the over-coating metering roller 51 in a closed space down to a small gap. The paint transfer from the applicator roll 50 and the material web 37 takes place here, for example, in the so-called "synchronization". Other versions of the dosing process are alternatively possible.

Downstream of the coating unit 48, the endless third material web 37 is assigned a material web inspection device 52, which inspects the endless third material web 37, in particular on its outside 40, for faults. In particular, this material web inspection device 52 checks the flatness of the third material web 37. With regard to details and function of the material web inspection device 52, reference is made to FIGS WO 2014/128115 A1 directed.

Downstream of the web inspection device 52, the endless third web of material 37 is associated with a brand reading device 53, which is in particular capable of producing outside marks 72, 74 (FIG. Fig. 5 ) of the endless third material web 37 to read or capture. The tag reading device 53 conveniently operates without contact.

Downstream of the brand reading device 53, the endless third material web 37 is assigned an inkjet coating device 54 which applies at least one spatially limited inkjet coating region 55 to the endless third material web 37 on the outside. The at least one overcoat layer 49 is located between the at least one inkjet lacquer area 55 and the precoat 41. The at least one inkjet lacquer area 55 advantageously covers the at least one imprint 45 at least in regions, for example along its contours or over its entire area.

This arrangement of the at least one inkjet coating area 55 is conveniently achievable by the mark reading device 53. The marks 72, 74 detected by the mark reading device 53 provide information about the arrangement of the at least one print 45 and / or the position of the at least one inkjet paint area 55 to be produced. The inkjet coating device 54 has a corresponding inkjet coating control device 54a for this purpose.

Downstream of the inkjet coating device 54, the endless third material web 37 is provided with an inkjet coating drying device 56 for drying the endless third material web 37 or the at least one inkjet coating region 55. The drying takes place here thermally by infrared radiation and / or by hot air. A combination of both heat sources is particularly advantageous.

Downstream of the inkjet coating drying device 56, the endless third material web 37 is assigned a flash unit 57 and gloss measurement unit 57a, which measures an outside gloss of the endless third material web 37 or of the at least one inkjet coating region 55. The flash unit 57 makes it possible to control overprinting accuracy by directional reflection of the inkjet paint by mark reading. The marks 72, 74 preferably comprise at least one stroke, circle, semicircle, passport or at least one similar simple geometric shape. The desired corrections based thereon can be carried out by the inkjet coating device 54, which then receives corresponding signals.

Downstream of the flash unit 57 and gloss measurement unit 57a, the endless third material web 37 is assigned a moistening device 58, which feeds water, conveniently in the form of spray steam, which is opposite to the outside 40 onto the endless third web of material 37. As a result, a flatness and a homogeneous moisture profile of the third material web 37 can be guaranteed. It is advantageous if the humidifying device 58 has a zone circuit and can be regulated by the measured value of a downstream traversing humidity sensor.

Downstream of the storage device 30 and the moistening device 58 is a preheater 59, which comprises two superimposed pre-heating rollers 60. The preheating device 59, the one-sided laminated corrugated cardboard web 22 and the endless third, printed and over-painted material web 37 are supplied, both partially wrap around the respective preheating roller 60. The endless third material web 37 runs in the preheating device 59 below the single-faced laminated corrugated cardboard web 22, the outer side 40 of the endless third material web 37 facing down there facing away or the one-sided laminated corrugated cardboard web 22.

Downstream of the preheater 59, there is a gluing unit 61 with a gluing roller 62 partially immersed in a glueing bath. The one-sided laminated corrugated cardboard web 22 is in contact with the gluing roller 62 and is thus provided with glue from the glue bath. On the gluing roller 62, a metering roller 63 abuts peripherally 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 single-faced laminated corrugated cardboard web 22, wherein the outer side 40 of the endless third material web 37 turned down there or the one-sided laminated corrugated cardboard web 22 faces away.

Downstream of the gluing unit 61, there is arranged a heating pressure device 64, which comprises a horizontally extending heating table 65 with heating elements. Adjacent to the heating table 65, a pressure belt 67 guided by guide rollers 66 is arranged. Between the Andrückgurt 67 and the heating table 65, a pressure gap is formed through which the one-sided laminated, glued corrugated cardboard web 22 and the endless third, printed and over-painted material web 37 are guided. The endless third material web 37 runs in the heating pressure device 64 below the single-faced laminated corrugated cardboard web 22, wherein the outer side 40 of the endless third material web 37 facing down there facing away or the one-sided laminated corrugated cardboard web 22.

Downstream of the heating-pressing device 64 is a two-sided laminated endless corrugated cardboard web 68, which is printed on the outside and painted over. According to an alternative embodiment, more than three material webs are present.

Downstream of the heating presser 64 are a slitter / scorer (not shown) for slitting and corrugating the corrugated board web 68, a cross cutter for cross cutting the corrugated board web 68, a switch (not shown) for splitting the part made of the corrugated board web 68 Corrugated board webs in various planes and cross-cutting devices (not shown) for cross-cutting the part corrugated webs in corrugated sheets and stacking devices (not shown) arranged for stacking the corrugated paper sheets.

The at least one generated print 45 is optically extremely appealing. It is characterized by a very high-quality shine. Furthermore, this is extremely resistant to abrasion, since it is protected.

The following is with reference to Fig. 4, 5 a second embodiment described. In contrast to the previous embodiment, to the description of which reference is explicitly made here, the overpainting arrangement is preceded by a material web preheating device 69, which is arranged in particular upstream of the coating unit 48 and preferably adjacent thereto. The web preheating device 69 suitably comprises a web of pre-heat roller 70 around which the endless third web of material 37 is passed. It is expedient if a looping angle of the endless third material web 37 around the material web pre-heating roller 70 is adjustable so that the preheating of the endless third material web 37 is adaptable.

Downstream of the coating unit 48, a material web predrying apparatus 71 assigned to the endless third material web 37 is provided in order to expose the endless third material web 37 to predrying after the application of the at least one transparent overcoat layer 49. The web predrying device 71 is conveniently located upstream of the web inspection device 52 such that the endless third web of material 37 enters the web inspection device 52 in an at least partially dried condition.

Conveniently, the imprint check unit 47 senses the transverse marks 72 and longitudinal marks 74 applied to the endless third web of material 37. The corresponding distance information of the transverse marks 72 relative to one another and longitudinal marks 74 relative to one another are supplied via a signal line 73 to the size adaptation of the at least one inkjet coating area to the at least one print of the inkjet coating control device 54a. Alternatively or additionally, transverse cutting marks on the endless third material web 37 or their spacing from one another are detected. Alternatively, the size of the at least one print is detected and compared with a print template for size adjustment of the at least one Inkjetlackbereichs to the at least one print. Depending on the size adjustment, the inkjet coating device 54 is operated accordingly.

Combinations of the embodiments are possible.

Claims (14)

1. 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,

   characterized in that

   d) the overcoating arrangement comprises

   i) 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)

   ii) an inkjet-varnishing device (54) for inkjet-varnishing the printed material web (37) in regions with at least one inkjet-varnish region (55), and

   e) the corrugated-board machine comprises 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), wherein the positioning control preferably takes place on the basis of markings (72, 74) of the printed material web (37), and

   f) a marking-reading device (53) for the reading of markings (72, 74) arranged on the printed material web (37).
2. Corrugated-board machine according to claim 1, characterised in that 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) and, favourably, at least one dosage element (51) for dosed application of the at least one overcoating layer (49) onto the material web (37).
3. Corrugated-board machine according to claim 1 or 2, characterised in that 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 a detected moisture and/or layer thickness of the at least one overcoating layer (49).
4. Corrugated-board machine according to one of the preceding claims, characterised in that the inkjet-varnishing control device (54a) receives marking-position signals from the marking-reading device (53).
5. Corrugated-board machine according to one of the preceding claims, characterised in that the inkjet-varnishing device (54) is disposed downstream of the varnishing unit (48) in conveying direction (38) of the material web (37).
6. Corrugated-board machine according to one of the preceding claims, characterised in that an inkjet print drying device (46) for drying the printed material web (37) is disposed downstream of the inkjet printing device (44).
7. Corrugated-board machine according to one of the preceding claims, characterised in that a hot-pressing device (64) for connecting the printed and overcoated material web (37) to at least one further material web (22), especially at least one corrugated-board web, is disposed downstream of the overcoating arrangement, wherein preferably at least one moistening unit (58) is arranged between the overcoating arrangement and the hot-pressing device (64).
8. 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;

   - substantially full-faced overcoating a printed side (40) of the material web (37) with at least one overcoating layer (49) by means of a varnishing unit (48) of the overcoating arrangement;

   - inkjet varnishing of the printed material web (37) in regions with at least one inkjet-varnish region (55) by means of an inkjet varnishing device (54) of the overcoating arrangement;

   - positioning control of the at least one inkjet-varnish region (55) on the printed material web (37) by means of an inkjet varnishing device (54a), wherein the positioning control takes place on the basis of markings (72, 74) of the printed material web (37), and,

   - reading of the markings (72, 74) arranged on the printed material web (37) by means of a marking-reading device (53).
9. Method according to claim 8, characterized in that the at least one inkjet varnish region (55) is smaller in its area on the printed material web (37) than the at least one overcoating layer (49).
10. Method according to claim 8 or 9, characterized in that 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.
11. Method according to one of claims 8 to 10, characterised in that the at least one inkjet-varnish region (55) is characterised by a higher degree of gloss by comparison with the at least one overcoating layer (49).
12. Method according to one of claims 8 to 11, characterised in that a matching of the at least one inkjet-varnish region (55) to the at least one imprint (45) takes place.
13. Method according to one of claims 8 to 12, characterised by a control in a flow time of the at least one imprint (45) and/or of the overcoating (49, 55).
14. Method according to claim 13, characterised in that the flow time is controllable through pre-drying.

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