Method and system for printing

Abstract

A printing station (100) for a packaging material manufacturing system (10) is provided. The printing station (100) comprises a printing unit (110) configured to provide a print (40) at a preset position of a packaging material (12); a detection unit (130) arranged downstream of the printing unit (110) and configured to determine an actual lateral distance (Xc) between a reference position and the provided print (40); and a control unit (150) configured to store an expected lateral distance between the print (40) and the reference position, and to adjust the preset position of a subsequent print (40) based on a comparison between the expected lateral distance and the actual lateral distance (Xc).

Description

Technical Field

[0001] This invention relates to methods and systems for printing. In particular, it relates to solutions for controlling the position of printed objects in the high-speed production of packaging materials. Background Technology

[0002] Single-use packaging containers for food (e.g., liquids or semi-liquids) are typically made from packaging materials based on cardboard or cartons. The packaging materials for such known containers are often manufactured as laminates comprising a body layer of paper or cardboard and an outer, liquid-impermeable layer of thermoplastic.

[0003] On the inside of the laminate (i.e., the side facing the food contents of the packaging container made of the laminate), there is one or more inner layers containing a heat-sealable thermoplastic polymer.

[0004] Laminates may also have barrier layers to prevent light and / or gas from penetrating into the interior of the packaging container, such as metal layers (e.g., aluminum).

[0005] The appearance of packaging containers made from the aforementioned packaging materials depends on the decorations printed on the outer layer of the packaging material that forms the exterior of the container. These printed decorations are typically applied using high-speed flexographic printing processes. These processes are designed for high-speed printing of substrate rolls several meters wide, for example, in packaging material manufacturing plants.

[0006] For each color to be printed using flexographic printing, a printing plate is made and mounted on the circumference of a rotating printing cylinder. For packaging material manufacturing, this printing plate contains the repeating pattern to be printed. The repeat length is equal to the circumference of the printing cylinder when the printing plate is mounted on it, typically corresponding to 3-6 printing passes on packaging containers and can vary, for example, between 450 and 800 mm.

[0007] The width of the printing plate is typically chosen to allow for printing decorations on multiple channels simultaneously; each channel will eventually be separated and used by the packaging container manufacturing machine. Therefore, the roll of packaging material entering the flexographic printing process will be supplied with repeating printed patterns, each pattern designed for a single packaging container to be produced.

[0008] To increase printing speed, the printing plate width can correspond to twelve channels. Therefore, when the printing plate rotates once, it will provide the printed pattern for the packaging material on an area corresponding to up to 12*6 packaging containers to be produced.

[0009] The configuration of the printing plate is static, meaning that the printed pattern will be identical for all packaging containers produced using the same printing plate. However, in recent years it has been suggested to also offer dynamic printing on packaging materials, which can be used by the consumers of the produced packaging containers. As an example, dynamic printing could be a QR code containing specific information.

[0010] Due to its repetitive nature, this dynamic printing cannot be achieved using existing flexographic printing processes. Instead, it has been suggested to provide a separate printing station downstream of the flexographic printing processing equipment. A separate printing station can provide unique printing inline, for example, by implementing inkjet technology, allowing unique QR codes or other dynamic objects to be printed in areas of the packaging material; typically, each final packaging container will have dynamic printing.

[0011] The position of the dynamic print, i.e., the pattern printed by a separate printing station, must be registered so that it aligns with the print position of the flexographic printing process. To allow for readability of the dynamic print, the flexographic design may include specific areas that are typically unprinted or have a particular background color to accommodate the dynamic print. If the dynamic print position is misaligned, there is a significant risk that proper reading of the dynamic print cannot be achieved, or at least becomes much more difficult.

[0012] The correct positioning of dynamic printing is affected by several parameters. One important factor is that the packaging material may undergo dimensional changes as it passes through the packaging material manufacturing plant, especially through decorative printing units that include separate printing stations. For example, wrinkles may exist, which may necessitate adjustments to the dynamic printing position. Another issue affecting the roll size of the packaging material is humidity and the moisture content of the packaging material. Thin packaging materials, in particular, will expand and shrink laterally with changes in moisture content (e.g., due to the drying heat applied immediately after the flexographic printing process). Since the roll width is quite large, as mentioned earlier with up to 12 channels, any variation in the width of the packaging material can lead to mispositioning in dynamic printing, especially at the outer channels. Another factor to consider is the lateral movement of the packaging material roll. This movement is often referred to as serpentinization and results in slight offsets in the lateral positioning of the entire packaging material roll.

[0013] All of these factors can influence the positioning of printing relative to the decoration of packaging materials.

[0014] Therefore, there is a need for an improved method and system for printing that ensures the correct positioning of the printed pattern relative to existing features on the packaging material, even if the size or position of the packaging material changes during production. Summary of the Invention

[0015] One object of the present invention is to overcome, at least in part, one or more of the aforementioned limitations. In particular, the object is to automatically determine the correct position of the object to be printed and to adjust the dedicated printing unit so as to print the object at the desired position on the roll of packaging material.

[0016] To achieve these objectives, a printing station is provided. The printing station is arranged for use in a packaging material manufacturing system and includes a printing unit configured to provide printing at a preset position. The printing station also includes a detection unit arranged downstream of the printing unit and configured to determine the actual lateral distance between a reference position and the provided print. A control unit is configured to store the desired lateral distance between the print and the reference position and to adjust the preset position for subsequent prints based on a comparison between the desired lateral distance and the actual lateral distance.

[0017] There may be several printing units that can be controlled independently of each other.

[0018] Printing stations have proven advantageous because the printing location can be determined based on existing reference features on the packaging material, and any misalignment in the printing will be detected and corrected immediately, thus effectively reducing the amount of defects in the packaging material.

[0019] The printing station and the method using such a printing station provide an online registration system for lateral control to print dynamic design elements and / or markings (such as QR codes) that will ultimately be visible on the packaging container. The printing station described herein supports cost reduction by significantly reducing setup time and waste. The printing station provides closed-loop lateral control of the printing unit and online individual channel shrinkage compensation. Regardless of the impact of roll shrinkage on individual channels of the packaging material roll, the printing station proves to consistently print design elements at the desired locations.

[0020] In one embodiment, the reference position is the actual location of a reference feature of the packaging material. This reference feature can be, for example, a pre-printed object, such as a crease line print or a registration mark. Preferably, the reference position can be determined as a lateral location corresponding to an edge or corner of the reference feature. Optionally, the reference position can be determined as the center location of the reference feature.

[0021] Printing can be dynamic, meaning the design of the print is non-static, allowing it to change during the printing process. For example, two consecutive prints are not identical, but differ in some way. By allowing dynamic printing, prints can be designed to provide information to consumers. The information can be plain text or numbers, but is preferably provided as a QR code.

[0022] In one implementation, the control unit is configured to adjust the preset position for subsequent printing by moving the position of the printing unit. This has proven to be very robust because the linear movement of the printing unit can be controlled with extremely high precision.

[0023] A printing unit can include multiple laterally distributed printing units, each configured to provide printing at a unique preset location. This is advantageous because the printing unit can be used with wide rolls of packaging material manufactured as several adjacent channels. This also allows for dynamic laterally distributed printing, enabling two laterally adjacent prints to be printed simultaneously by different printing units, while the print design can be varied.

[0024] The detection unit may include multiple laterally distributed detection devices, each configured to determine a unique reference position and the actual lateral distance between the provided print. This has proven particularly advantageous for wide rolls of packaging material. Especially when the lateral width of the packaging material roll varies, for example as a result of changes in the moisture content of the packaging material, the adjustment of the preset position is not necessarily constant across the width of the packaging material (i.e., for different channels). Therefore, individual control of each preset position is preferred and is made available by providing several independent detection devices.

[0025] According to a second aspect, a packaging material manufacturing system is provided. This packaging manufacturing system includes a decorative printing system and a printing station as described in the first aspect. The printing station is located downstream of the decorative printing system.

[0026] According to a third aspect, a method for providing printing to packaging material via a printing station is provided. The method includes actuating a printing unit to provide printing at a preset position on the packaging material, determining an actual lateral distance between a reference position on the packaging material and the provided printing, and adjusting the preset position for subsequent printing based on a comparison between a desired lateral distance between the reference position and the provided printing and the actual lateral distance.

[0027] The method can further include feeding a continuous roll of packaging material through a printing station, wherein the following actions are repeatedly performed: actuating the printing unit, determining the actual lateral distance, and adjusting the preset position. Therefore, the printing station can be used for linear production, thereby achieving high printing speeds.

[0028] The packaging material can be provided with multiple consecutive reference features, each defining a unique reference position. In such an implementation, the printing unit is repeatedly actuated to provide printing at a predetermined position on the packaging material for each reference feature passed through the printing unit.

[0029] The actuated printing unit may include actuating multiple laterally distributed printing devices, each configured to provide printing at a unique preset position.

[0030] The actual lateral distance can be determined by actuating multiple laterally distributed detection devices, each configured to determine a unique reference position and the actual lateral distance between the provided print.

[0031] According to a fourth aspect, a method for manufacturing packaging material is provided. The method includes feeding a roll of packaging material through a decorative printing system to provide decoration to the packaging material, and subsequently providing printing to the packaging material by performing the method according to a third aspect.

[0032] Other objects, features, aspects and advantages of the invention will become apparent from the following detailed description and the accompanying drawings. Attached Figure Description

[0033] Embodiments of the invention will now be described by way of example with reference to the accompanying drawings, wherein...

[0034] Figure 1 This is a schematic diagram of a packaging material manufacturing system according to one implementation plan;

[0035] Figure 2 This is a schematic side view of a printing station (which forms part of a packaging material manufacturing system) according to one embodiment;

[0036] Figure 3 It provides photos of packaging materials with decorative and dynamic printing;

[0037] Figure 4 This is a schematic diagram of a method for using packaging materials according to one embodiment;

[0038] Figure 5 This is a schematic diagram of a method for providing dynamic printing according to one embodiment;

[0039] Figure 6 This is a top view of a printing station according to one implementation plan;

[0040] Figure 7 It is a schematic diagram of packaging materials processed by a printing station according to the first embodiment; and

[0041] Figure 8 This is a schematic diagram of packaging materials processed by a printing station according to the second implementation plan. Detailed Implementation

[0042] refer to Figure 1The diagram illustrates a packaging material manufacturing system 10. The packaging material manufacturing system 10 includes a decorative printing system 20 and a printing station 100 arranged downstream of the decorative printing system 20.

[0043] The roll of packaging material 12 is wound onto a reel 14 and continuously fed through the packaging material manufacturing system 10 in the direction of the box arrow. The roll of packaging material 12 is preferably pre-manufactured as a laminate comprising a body layer of paper or cardboard and an outer liquid-impermeable layer of thermoplastic, as well as one or more inner layers comprising a heat-sealable thermoplastic polymer and a barrier layer.

[0044] The decorative printing system 20 is preferably a flexographic printing system, comprising a series of flexographic printing units 22a to 22d. Each flexographic printing unit 22a to 22d includes a plate cylinder 24a to 24d and an impression cylinder 26a to 26d. The plate cylinders 24a to 24d and the associated impression cylinders 26a to 26d form a roll gap through which the roll of packaging material 12 is fed, thereby transferring ink from the plate cylinders 24a to 24d to the roll of packaging material 12. In the example shown, four flexographic printing units 22a to 22d are illustrated. Each flexographic printing unit 22a to 22d is responsible for a specific color; in one example, the flexographic printing units 22a to 22d provide each of the CMYK color schemes. Each flexographic printing unit 22a to 22d may include additional components, such as anilox rollers and ink fountain rollers known in the art.

[0045] The decorative printing system 20 optionally includes a drying unit 28. The drying unit 28 is arranged downstream of the flexographic printing units 22a to 22d. The drying unit 28 can be operated by providing IR radiation or hot air to the roll of packaging material 12, thereby drying the ink on the roll of packaging material 12.

[0046] It should be noted that the decorative printing system 20 is not necessarily a flexographic printing system, but other well-known techniques may also be used to decorate the roll of packaging material 12.

[0047] Once the roll of packaging material 12 is decorated, it passes through printing station 100. Printing station 100 includes printing unit 110, detection unit 130 arranged downstream of printing unit 110, and control unit 150. Control unit 150 is connected to printing unit 110 and detection unit 130, as follows: Figure 1 As indicated by the arrow in the diagram. Optionally, the printing station 100 may further include a drying unit 170 arranged downstream of the detection unit 130. The drying unit 170 is preferably a hot air supplier that directs heated airflow to the roll of packaging material 12.

[0048] During operation, and as will be described in further detail below, printing station 100 is configured to repeatedly supply printing to the roll of packaging material 12, and to ensure that the printing and decoration are aligned to a level of precision unattainable by existing technologies. Advantageously, printing station 100 is arranged online with the upstream decorative printing system 20.

[0049] As will be explained below, printing station 100 allows for closed-loop lateral control of the printing unit. Detection unit 13 (provided, for example, as one or more line scanners or cameras) is configured to measure the distance between a fixed point in the decorative design and the center of print. Possible error corrections are looped back to the position controller (i.e., control unit 150), and preferably all channels are checked simultaneously.

[0050] exist Figure 2 A more detailed example of printing station 100 is shown in the figure. The roll of packaging material 12 is conveyed through various rollers before passing through printing unit 110. The reason for not immediately passing through printing unit 110 after entering the printing station is not only to allow for accurate control of the tension of the roll of packaging material 12, but also to allow for sufficient drying of decorations applied earlier in the packaging material manufacturing process, and to allow for additional packaging material treatments to be performed within printing station 100, such as splicing, cleaning, and dust removal.

[0051] Printing unit 110 includes one or more print heads 112a to 112c spaced apart along the travel direction of the roll of packaging material. Inspection unit 130 is arranged downstream of printing unit 110 and upstream of a series of hot air dryers 170. After leaving printing station 100, the roll of packaging material 12 is prepared for further processing, such as cutting, winding, etc.

[0052] Printing station 100 allows for a novel and significantly improved combination of static decorative printing and dynamic content printing on rolls of packaging material 12 (especially regarding the accurate positioning of dynamic printing related to decorative design).

[0053] exist Figure 3 The image shows a portion of the packaging material. The photo shows the outer side of the packaging material, which is printed with decorations to provide information and an attractive design to consumers. (See image for details.) Figure 3 As shown, packaging materials are manufactured to form packaging containers for storing almond milk.

[0054] The decorative design covers the entire packaging material and includes area 30. Within this area 30, a QR code 40 is printed. In the example shown, area 30 is a light color, while the QR code printing 40 is a dark color. Due to the design of the decorative feature, the correct positioning of the printed code 40 is important to ensure its visibility and readability. Although the decorative feature is printed using decorative printing system 20, the QR code 40 is printed using printing station 100.

[0055] Turn now Figure 4 A general method 200 for manufacturing packaging materials will be briefly described below. Method 200 is preferably performed by operating the packaging material manufacturing system 10 as described above. Method 200 includes a first step 202 of providing packaging materials. The packaging materials are preferably intended for subsequent forming, filling, and sealing into individual liquid food packaging containers, and generally comprise a body layer of paper or cardboard and an outer liquid-tight layer of thermoplastic plastic, as well as one or more inner layers comprising a heat-sealable thermoplastic polymer. In a subsequent step 204, a decoration is printed onto the outer side of the packaging material. The decoration is preferably designed with at least one area for receiving the printing, which is provided in a subsequent step 300.

[0056] refer to Figure 5 Further description of the subsequent step 300, which provides printing, Figure 5 A schematic diagram is provided of a method for applying printing (e.g., dynamic codes) to packaging material after printing decoration. Therefore, method 300 can form part of method 200.

[0057] As a fundamental principle, method 300 preferably operates by using features of the decorative design as a reference for dynamic printing, and by online detection of the actual positioning of the dynamic print relative to the decorative reference. When misalignment of the dynamic print is detected, the position of subsequent dynamic prints is adjusted. Therefore, method 300 applies closed-loop control of the position of the dynamic print.

[0058] Starting at step 302, the desired printing position is determined. The desired position is stored as a preset position and is preferably determined relative to a 2D coordinate system. In this coordinate system, the position of a reference feature is known, such that the desired printing position is set relative to the reference feature. As will be explained below, the reference feature is preferably a decorative feature of the packaging material.

[0059] In step 304, the lateral distance between the preset position and the reference feature is determined as the desired lateral distance. This is done automatically without any visual inspection of the packaging material, as the position of the reference feature can be obtained from the decoration design documents.

[0060] As the roll of packaging material is conveyed through printing station 100, in step 306, printing is performed at the desired preset position by actuating the printing unit 110 of the printing station.

[0061] Once printing is provided in step 306, image data containing both printing and reference features is captured in step 308.

[0062] Based on the image data, the actual lateral distance between the printed and reference features is determined in step 310. In step 312, the actual lateral distance is compared with the desired lateral distance, and in step 314, any adjustments to the preset position are calculated. This newly calculated preset position is fed back to the initial steps of method 300, which is continuously repeated as the printing station 100 operates. Therefore, any misalignment in the printing will be immediately detected, and correction will be performed through the closed-loop control characteristics of method 300.

[0063] To further understand the functions of printing station 100, please refer to... Figure 6 Here, a schematic diagram of the roll of packaging material 12 is shown above.

[0064] Assume that the packaging material 12 is provided with decoration and is fed through the printing station 100 in the direction of the box arrow. As previously explained, the printing station 100 includes a printing unit 110, a detection unit 130, a control unit 150, and an optional drying unit 170.

[0065] The width of the packaging material 12 is chosen such that it is divided into multiple channels 50. These channels 50 will ultimately be separated for individual use in a packaging container manufacturing machine, and the width of each channel 50 corresponds to the total width of the roll of packaging material 12 required to form a single packaging container. In the example shown, the roll of packaging material has twelve channels 50. The decoration of each channel 50 is longitudinally divided into repeating segments 52. The roll of packaging material 12 covered by a single repeating segment 52 will ultimately form a single packaging container.

[0066] from Figure 6 As can be seen, each repeating segment 52 of each channel 50 is provided with a reference feature 60. This reference feature 60 can be of various types, such as reference... Figure 7 and Figure 8 To further explain, it should be detectable by the detection unit 130 and have a clearly defined location on the roll of packaging material 12.

[0067] Printing unit 110 is shown herein as a print head 112 that extends across the width of the roll of packaging material 12, i.e., across all channels 50. However, it should be recognized that, as Figure 2 As shown, the printing unit 110 can be formed by several longitudinally spaced printing heads 112.

[0068] The printing unit 110 includes a plurality of printing devices 114 spaced laterally (i.e., along the width of the roll of packaging material 12). Each printing device 114 is configured to provide printing 40 to the roll of packaging material 12 and may be in the form of an inkjet printing device.

[0069] Control unit 150 is configured to control the operation of printing apparatus 114. Actuation of printing apparatus 114 is achieved by determining the design and position of print 40. Due to the inherent characteristics of inkjet technology, printing apparatus 114 can change the print design during operation of printing station 100, so that repeating section 52 provides dynamic printing.

[0070] The position of each print 40 is determined by defining a preset position. The preset position is initially defined by the decorative design, which typically provides an area 30 intended to hold the print 40 (see [reference]). Figure 3 The lateral preset position of the printing 40 is determined by defining a coordinate system in the plane of the packaging material 12 roll and by determining the assumed position of the packaging material 12 roll and the assumed position of region 30. Although not explained in further detail here, the longitudinal preset position of the printing 40 is determined by: determining the speed of the packaging material 12 roll, setting the timing of the actuation of the printing device 112, and adjusting the timing to correctly position the printing 40 longitudinally.

[0071] The detection unit 130 is arranged downstream of the printing unit 110 and includes a plurality of detection devices 132. Each detection device 132 is preferably a camera configured to capture an image of the roll of packaging material 12 as it passes beneath the detection device 132. However, it should be noted that the detection unit 130 may include only a single camera covering the entire width of the roll of packaging material 12 (i.e., all channels 50).

[0072] Based on the captured image, for each repeating segment 52, the actual lateral distance between the print 40 and the reference feature 60 is calculated. The control unit 150 is further configured to compare the actual lateral distance with a desired lateral distance between the print 40 and the reference feature 60; this desired lateral distance is preferably determined based on decorative design data. In the event of any deviation between the actual lateral distance and the desired lateral distance, the control unit 150 is configured to adjust the preset position of subsequent prints 40 so that these prints are correctly positioned on the repeating segment 52.

[0073] Preferably, the preset position adjustment of the printing 40 is performed by laterally moving the printing unit 110 to correct misalignment of the print 40 relative to the decoration (particularly relative to the reference feature 60). In practice, for embodiments using multiple printing units 114, each printing unit 114 can be moved individually and / or independently, allowing for individual control of the position of each printing unit 114. For this purpose, each printing unit 114 may be provided with a drive unit (not shown) capable of laterally shifting the position of the associated printing unit 114. Preferably, the drive unit is capable of adjusting the lateral position at a sub-millimeter level.

[0074] An example of repeating segment 52 is shown in Figure 7 and Figure 8 These figures show portions of the roll of packaging material 12 with printed decorations and dynamic printing 40.

[0075] from Figure 7 The starting point is initially set at the lateral edge of the roll of packaging material 12. Reference feature 60 is a printed K-mark, a specific mark used to identify the alignment of crease lines formed on the packaging material. When creases form in the packaging material, the specific K-mark crease line is visually enhanced by printing the same K-mark design onto the crease line during the decorative printing process. The lateral distance X between the starting point and the center of the K-mark is determined by the decorative design data, and therefore also by the desired lateral distance between the print 40 and the reference feature 60. Although the actual lateral distance Xc is measured using printing station 100, the measured lateral distance Xc is used in the control loop of printing station 100.

[0076] exist Figure 8 In this process, the starting point is also set at the lateral edge of the roll of packaging material 12. Reference feature 60 is a registration mark on the packaging material, which is preferably printed during the decorative printing process. The lateral distance X between the starting point and the lateral end of the registration mark 60 is determined by the decorative design data, and therefore also by the desired lateral distance between the printing 40 and the reference feature 60, since this desired lateral distance is also determined by the decorative design data. Although the actual lateral distance Xc is measured using printing station 100, the measured lateral distance Xc is used in the control loop of printing station 100.

[0077] As described above, the control parameter Xc is measured as the lateral distance between the print 40 and the reference feature 60. In one embodiment, the control parameter Xc is measured from the lateral end of the reference feature 60 to the center of the print 40. In another embodiment, the control parameter Xc is measured from the center of the reference feature 60 to the center of the print 40. In yet another embodiment, the control parameter Xc is measured from the lateral end of the reference feature 60 to the lateral end of the print 40, or Xc is measured from the center of the reference feature 60 to the lateral end of the print 40.

[0078] As can be seen from the above description, although various embodiments of the present invention have been described and illustrated, the present invention is not limited thereto, but may be implemented in other ways within the scope of the subject matter defined in the appended claims.

Claims

1. A printing station (100) for a packaging material manufacturing system (10), said printing station (100) comprising: A printing unit (110) is configured to provide printing (40) at predetermined positions on the packaging material (12). A detection unit (130), which is arranged downstream of the printing unit (110) and configured to determine the actual lateral distance (Xc) between the reference position and the provided print (40), and A control unit (150) is configured to store the desired lateral distance between the print (40) and the reference position, and to adjust the preset position of subsequent prints (40) based on a comparison between the desired lateral distance and the actual lateral distance (Xc). The printing unit (110) includes a plurality of horizontally distributed printing devices (114), each of the printing devices (114) being provided with a drive unit capable of horizontally shifting the position of the associated printing device (114), wherein the drive unit is capable of adjusting the horizontal position.

2. The printing station (100) according to claim 1, wherein the reference position is the actual position of the reference feature (60) of the packaging material (12).

3. The printing station (100) according to claim 2, wherein the reference feature (60) is a pre-printed object.

4. The printing station (100) according to claim 3, wherein the pre-printed object is a zigzag print or a registration mark.

5. The printing station (100) according to any one of the preceding claims, wherein the printing (40) is a QR code.

6. The printing station (100) according to any one of the preceding claims, wherein the control unit (150) is configured to adjust a preset position of subsequent printing (40) by moving the position of the printing unit (110).

7. The printing station (100) according to any one of the preceding claims, wherein each printing device (114) is configured to provide printing (40) at a unique preset position.

8. The printing station (100) according to any one of the preceding claims, wherein the detection unit (130) comprises a plurality of laterally distributed detection devices (132), each detection device (132) being configured to determine a unique reference position and the actual lateral distance (Xc) between the provided print (40).

9. A packaging material manufacturing system (10) comprising a decorative printing system (20) and a printing station (100) arranged downstream of said decorative printing system (20) according to any one of the preceding claims.

10. A method for providing printing for packaging material via a printing station, the method comprising: The actuated printing unit provides printing at predetermined positions on the packaging material. Determine the actual lateral distance between the reference position on the packaging material and the provided printing, and The preset position of subsequent printing is adjusted based on a comparison between the reference position and the expected lateral distance between the provided print and the actual lateral distance. Adjusting the preset position for subsequent printing includes laterally shifting the position of the associated printing device by means of a drive unit located in each printing device of the printing unit, the printing unit comprising multiple laterally distributed printing devices, wherein the drive unit is capable of adjusting the lateral position.

11. The method of claim 10, further comprising supplying a continuous roll of packaging material through the printing station, wherein repeatedly performing: actuating the printing unit, determining the actual lateral distance, and adjusting the preset position.

12. The method of claim 11, wherein the packaging material is provided with a plurality of consecutive reference features, each reference feature defining a unique reference position, wherein for each reference feature of the printing unit, the actuation of the printing unit to provide printing at a predetermined position on the packaging material is repeatedly performed.

13. The method according to any one of claims 10 to 12, wherein actuating the printing unit comprises actuating a plurality of laterally distributed printing devices, each printing device being configured to provide printing at a unique preset position.

14. The method according to any one of claims 10 to 13, wherein determining the actual lateral distance is performed by actuating a plurality of laterally distributed detection devices, each detection device being configured to determine the actual lateral distance between a unique reference position and the provided print.

15. A method for manufacturing packaging material, the method comprising: The roll of packaging material is fed through a decorative printing system, thereby providing decoration to the packaging material, and then printing is provided to the packaging material by performing the method according to any one of claims 10 to 14.

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