EP4200584A1 - Procédé pour l'impression d'une décoration, et appareil pour celui-ci - Google Patents

Procédé pour l'impression d'une décoration, et appareil pour celui-ci

Info

Publication number
EP4200584A1
EP4200584A1 EP21766160.2A EP21766160A EP4200584A1 EP 4200584 A1 EP4200584 A1 EP 4200584A1 EP 21766160 A EP21766160 A EP 21766160A EP 4200584 A1 EP4200584 A1 EP 4200584A1
Authority
EP
European Patent Office
Prior art keywords
measurement data
printed
digital template
decor
decoration
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
EP21766160.2A
Other languages
German (de)
English (en)
Inventor
Sabrina Pfeiffer
Sebastian Dicke
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Swiss Krono Tec AG
Original Assignee
Swiss Krono Tec AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Swiss Krono Tec AG filed Critical Swiss Krono Tec AG
Publication of EP4200584A1 publication Critical patent/EP4200584A1/fr
Pending legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J3/00—Spectrometry; Spectrophotometry; Monochromators; Measuring colours
    • G01J3/28—Investigating the spectrum
    • G01J3/2823—Imaging spectrometer
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J11/00—Devices or arrangements  of selective printing mechanisms, e.g. ink-jet printers or thermal printers, for supporting or handling copy material in sheet or web form
    • B41J11/008—Controlling printhead for accurately positioning print image on printing material, e.g. with the intention to control the width of margins
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
    • B41M5/00—Duplicating or marking methods; Sheet materials for use therein
    • B41M5/0041—Digital printing on surfaces other than ordinary paper
    • B41M5/0047—Digital printing on surfaces other than ordinary paper by ink-jet printing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
    • B41M5/00—Duplicating or marking methods; Sheet materials for use therein
    • B41M5/0041—Digital printing on surfaces other than ordinary paper
    • B41M5/0076—Digital printing on surfaces other than ordinary paper on wooden surfaces, leather, linoleum, skin, or flowers
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J3/00—Spectrometry; Spectrophotometry; Monochromators; Measuring colours
    • G01J3/46—Measurement of colour; Colour measuring devices, e.g. colorimeters
    • G01J3/50—Measurement of colour; Colour measuring devices, e.g. colorimeters using electric radiation detectors
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2203/00—Embodiments of or processes related to the control of the printing process
    • B41J2203/01—Inspecting a printed medium or a medium to be printed using a sensing device
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/84—Systems specially adapted for particular applications
    • G01N2021/8411—Application to online plant, process monitoring
    • G01N2021/8416—Application to online plant, process monitoring and process controlling, not otherwise provided for

Definitions

  • the invention relates to a method for printing a decoration to be printed on a plurality of print surfaces using a digital printing system.
  • the invention also relates to a device for carrying out such a method.
  • decorations are now printed on the surfaces of objects in order to enhance or change the visual impression.
  • wood-based panels that are used as floor, wall or ceiling paneling are provided with a decor.
  • the decor can be applied directly to the wood-based panel or a primer on the panel, or the decor is applied to a decor paper that is later applied to the wood-based panel, for example laminated or glued.
  • the quality of the print result depends on a large number of different parameters, which can often vary within a production series and in many cases cannot be controlled or influenced, or only with difficulty, by the operator of the printing system. can be flown. Cloudiness, i.e. an inhomogeneous color of the paper, can occur during the production itself. The waviness or the color can also lead to deviations in the printed image.
  • An applied undercoat or primer can also affect the print result.
  • the temperature, the color and, if necessary, the viscosity as well as the application accuracy of the operator are parameters that can influence the printed decor.
  • the respective job is dried, which can also influence the color and thus the print quality.
  • a primer is a layer on which the colored print dots forming the respective decor are applied. This layer can also be called the primer.
  • the layer does not have a basic color, for example white, in order to compensate for irregularities in color on the surface of the workpiece to be printed and to ensure reproducible and predictable basic conditions for printing the decoration.
  • the layer is designed as an ink-receptive layer and does not change or not only the optical appearance of the surface, for example its color, but rather the ability to absorb the color.
  • Printed decors are used in many technical areas and today determine the visual appearance of numerous products.
  • a high print quality is particularly important when many individual objects, each of which is printed with a decoration, are used together. This applies, for example, to panels that are used as wall, ceiling or floor coverings. To do this, several panels are connected to one another and laid. Products from different manufacturing batches are often mixed together. turns. In order to be able to guarantee a uniform appearance, it must be ensured that the printed image of panels from different batches does not differ from one another. This is just as important for follow-up deliveries, which are necessary, for example, when a defective panel or product has to be replaced.
  • WO 2020/079067 A1 discloses a method in which a first color value is initially determined at a point on the decoration to be printed.
  • the decor is printed using an inkjet printer.
  • a second color value is then determined by measuring at the same point on the printed decor.
  • a third color value is determined via a conversion module, which is then compared with the first color value. If the deviation is greater than a predetermined limit, production is stopped.
  • the disadvantage is that the printed decor cannot be directly compared with a desired result. Rather, the measured value must be converted by the conversion module in such a way that it corresponds to a digital desired value.
  • this process is only carried out in a few places on the decoration, so that fluctuations in the quality of the decoration can only be determined with difficulty or not at all.
  • deviations may be identified, but cannot be corrected by the procedure.
  • WO 2019/234147 A1 takes a different approach.
  • the print values on which the print is based are changed when determining deviations in order to improve the quality.
  • a hyperspectral digital image of the decor is first generated. This is calibrated by, for example, averaging several of these hyperspectral digital images.
  • a hyperspectral image contains information not only about the visible part of the color spectrum, but also beyond. It is expensive to capture and contains a large amount of data, making such images expensive to display and process. Therefore a digital target image is generated from the calibrated hyperspectral image, which is generated for example by a digital photograph. Such an image is also generated as an actual image of the printed decor, so that the two images can be compared with one another.
  • the invention is based on the object of eliminating or at least alleviating the disadvantages of the prior art.
  • the invention solves the problem set by a method for printing a decoration to be printed on a plurality of print surfaces by means of a digital printing system, the method having the following steps: a. Providing a digital template and reference measurement data of a decoration to be printed, which are hyperspectral and spatially resolved, b. Printing the decor to be printed on a print surface using the digital template, c. Measuring metrics of the decor printed on the print surface, so that print metrics are obtained that are hyperspectral and spatially resolved, d. comparing the pressure measurement data with the reference measurement data and determining a measure of a deviation of the pressure measurement data from the reference measurement data, e. changing the digital template if the degree of deviation meets a predetermined criterion, f. repeating steps b. to f.
  • the comparison of the printed decor with the decor to be printed is carried out in the method according to the invention using the various measurement data. It the pressure measurement data is compared with the reference measurement data.
  • the reference measurement data consequently correspond to the data that were or would be measured on a decor that can serve as a reference, ie corresponds exactly to the desired decor.
  • the finding on which the invention is based is therefore that it is not necessary to compare entire images with one another in order to determine the quality of the printed decoration if measurement data can be defined, the comparison of which for the printed decoration and the decoration to be printed enables the comparison of the Images or the entire decors superfluous.
  • the measurement data are spatially resolved, so that fluctuations in the print quality, which can arise in particular from the parameters listed above, can also be determined, even if they occur on a spatially small scale, for example within a single printed decor.
  • the measurement data is hyperspectral, so that information beyond the visible light is also included and can be compared.
  • the digital template preferably corresponds to the control parameters with which the printing system is controlled. This applies in particular to control commands about what amount of ink should be applied to which point on the print surface.
  • the control parameters preferably contain all the information required to operate a printing unit of the printing system.
  • a deviation is found when comparing the pressure measurement data with the reference measurement data, which deviation fulfills a predetermined criterion, for example exceeds a predetermined deviation, this deviation is reacted to appropriately. This is done in particular by changing the digital template. As a result, in the case of a decor printed with the changed digital template, the extent of the deviation is smaller and the predetermined criterion may therefore no longer be met. If the criterion is not met, the printed decor corresponds to the desired decor in terms of quality. If, on the other hand, the criterion is met, an adjustment of the digital template is necessary, so that it can be assumed that the printed decor does not meet the print quality requirements and must be sorted out as scrap.
  • a time interval between two consecutive executions of step b. regardless of whether the digital template has been modified.
  • the production in particular the cycle with which the decor is printed on the print surfaces, is therefore not changed, so that the digital template can be corrected or changed inline, i.e. without interrupting or delaying the production process.
  • step a The provision of the reference measurement data in step a. following steps: a1 . Providing a digital template of a decor to be printed, a2. Printing the decor to be printed using the digital template on a reference surface, a3. Measuring the metrics of the decor printed on the reference surface so that the reference measurement data is obtained.
  • the digital template of a decoration to be printed is made available to the printing system in a manner known per se from the prior art.
  • the printing system is controlled by this digital template to print the decor to be printed on the reference surface.
  • the reference surface preferably corresponds in material, size, feel and/or color to the print surfaces to be printed in the course of the method.
  • the decor printed on the reference surface is then measured by measuring the metrics. In this way, reference measurement data are obtained.
  • a conversion tool can be used to perform a conversion so that the various measurement data correspond better to one another. However, this is principally subject to errors and therefore it is advantageous if the respective surfaces match as well as possible.
  • the reference measurement data which is generated in method step d. on which the comparison is based, are actual measurement data that cannot be taken from a digitally available template stored in an electronic data storage medium.
  • the predetermined criterion is met when a deviation of one or more of the pressure measurement data from the corresponding reference measurement data is greater than a limit value predetermined for the corresponding measurement variables.
  • the predetermined limit value is particularly preferably dependent on color and/or location. In this way weightings can be made. If, for example, a particular color has a very large effect for a certain decor, for example because it stands out brightly or because a lot is used to print the decor, it is advantageous to ensure that the deviation is particularly small with this color. In this case, the color-dependent limit value for this color is selected to be particularly small, so that even relatively small deviations mean that the digital template has to be changed.
  • the color-dependent limit value can be selected. same applies to location dependencies. Deviations at the edge of the decoration may be less relevant than deviations directly in the field of vision, for example in the middle of the decoration.
  • step e changing the digital template in step e. following steps: e1 . Check whether the degree of deviation meets a correction criterion and e2a. Changing the digital template or e2b. Outputting an optical and/or acoustic and/or electronic warning signal and ending the method.
  • Some discrepancies between the reference measurement data and the print measurement data are due to reasons that cannot be remedied by changing the digital template, for example. This concerns, for example, the case that an incorrect primer was applied or color changes were caused by a change of supplier for printing ink or base paper. This cannot or can hardly be remedied by changing the digital template, so that in this case a correction criterion is not met.
  • the correction criterion indicates whether the deviation detected by the measure of the deviation can be corrected by changing the digital template. If this is the case, the decor is changed according to step e2a. Otherwise, according to step e2b, the method is aborted and a corresponding warning signal is output.
  • steps c. to e. of the method at least one further printing surface is printed with the decoration to be printed.
  • the correction or modification of the digital template has no effect on the decor that is printed directly afterwards.
  • the changes to the digital template only become effective for the decor after next or an even later one.
  • they are printed with a digital template that has not yet been modified they contain the same error as this has not yet been corrected. she are therefore also faulty and thus possibly produced as scrap.
  • the question of how many more print surfaces to use during steps c. to e. are printed depends on the performance of an electronic data processing device that is responsible for these steps and carries them out. The faster the data processing device can carry out the steps, the sooner the necessary change to the digital template will be available and the fewer additional decorations will be printed.
  • the cycle frequency of the printing system also has a major influence on this.
  • Changes to the digital template and/or the ascertained dimensions of the deviation for the different runs of the method are preferably stored and preferably stored in an electronic data memory.
  • the pressure measurement data preferably relate to the same points and/or the same area of the decoration as the reference measurement data. This makes it particularly easy to compare the respective measurement data with one another.
  • the print measurement data and the reference measurement data relate to the entire decor. This means in particular that there are a large number of measurement points at which the respective measurement data are determined, and this large number of measurement points extends over the entire decor.
  • the measuring points are preferably distributed equidistantly over the decoration.
  • a device for carrying out a method of the type described here includes an electronic data processing device, in particular a computer or a microchip, which is set up to carry out the method.
  • the device has at least one sensor that is set up to record the measurement data.
  • the at least one sensor transmits the measurement data as signals to the electronic data processing device, which receives them with a receiving module.
  • a comparison module compares the measurement data transmitted by the at least one sensor with reference measurement data, which is preferably stored in an electronic data storage device to which the receiving module has access. are chert. In this way, a measure of the deviation is determined, which is then transferred to an evaluation module. This evaluation module checks whether the extent of the deviation has met a predetermined criterion.
  • the change that needs to be made to the digital template is determined in a change module. This is then transmitted to the printing system so that the next decor to be printed is printed using the changed digital template.
  • the reception module, the comparison module, the evaluation mode and the change module are implemented in the electronic data processing device and can be embodied as software, ie in particular as a computer program product.
  • the digital template does not correspond to the entire decor, but only to a part. This makes sense if, for example, the data processing capacity is not sufficient to use the entire decor as a basis for the process. In addition, it must be ensured that deviations that are only found in the part of the decor that corresponds to the digital template are meaningful for the overall decor.
  • an ACMS or AVT monitoring system can be used to acquire the measurement data.
  • the measurement data is recorded, for example, in the lab system. This measurement data can easily be compared with one another, with Lab values or hyperspectral lines, for example, being compared with one another which, for example, have a resolution of preferably 80 to 100 dpi, particularly preferably 90 dpi for each measured value.
  • a measure for the deviation can be determined in this way, which can be specified as a percentage. In this way, it is particularly easy to determine criteria which, if met, require the digital template to be changed.
  • the method is ended when 3, preferably 5, particularly preferably 10 consecutive changes to the digital template have not resulted in the extent of the deviation exceeding the predetermined criterion no longer met, i.e. the printed decors meet the desired quality standard.
  • An electronic certificate is preferably created for the decor printed on the print surface and particularly preferably stored if the extent of the deviation does not meet the predetermined criterion, ie the desired quality is present.
  • the working width of a digital printing system is preferably at least 1300 mm, preferably at least 1600 mm, particularly preferably at least 2000 mm and at most 2300 mm, preferably at most 2200 mm and particularly preferably at most 2100 mm.
  • the speed of the system at which the surface to be printed is moved through the system when printing paper is preferably at least 80 m/min, preferably at least 100 m/min and particularly preferably at least 130 m/min and at most 270 m/min, preferably at most 200 m/min and particularly preferably at most 140 m/min.
  • the speed is preferably at least 60 m/min, preferably at least 70 m/min and particularly preferably at least 80 m/min and at most 110 m/min, preferably at most 100 m/min and particularly preferably at most 90 m /min
  • the amount applied is preferably at least 1 g/m 2 , preferably at least 2 g/m 2 and particularly preferably at least 3 g/m 2 and at most 10 g/m 2 , preferably at most 6 g /m 2 , particularly preferably at most 4 g/m 2 .
  • a wood decor was printed on paper using a digital paper printing system.
  • the working width was 2070 mm.
  • the speed was 135 m/min.
  • a white decorative paper with a basis weight of 65 g/m 2 and water-based CRYK ink and an inline primer application of approx. 3 g/m2 is used.
  • the wood decor had repeat dimensions of 1400 mm in length and 2070 mm in width.
  • An ipac inline monitoring system was installed across the entire width (2070 mm) of the production plant.
  • a digital template of the decor was saved. During production, print measurement data was recorded and saved for every repeat, i.e. every printed decor.
  • the similarity index i.e.
  • a measure of the deviation from the reference measurement data is calculated from this pressure measurement data.
  • the predetermined criterion was set at 92% before the start of production. So if the degree of deviation falls below 92% in this case, the digital template must be changed. A similarity index of 89% was calculated for the repeat 1,264 produced.
  • the measurement data showed that the deviation in this case is essentially on the b-axis, ie on the yellow-blue line (eg 5% to blue). Since the deviation is above the specified tolerance, the measurement data is automatically transferred to the Colorgate software and a corrected digital template of the wood decor is calculated and saved. After automatic transfer to the output device, i.e.
  • the print file (digital template) previously used for the print job is automatically replaced by the corrected digital template of the wood decor and made available as a print file for the following report.
  • a similarity index of 94% is calculated from the next print measurement data to the reference measurement data.
  • the period from the measurement of the pressure measurement data of an entire decor to the output of the modified digital template of the wood decor was one repeat length (approx. 0.62 seconds). In this case, an entire repeat was measured, saved and a deviation was identified. The subsequent report is still printed with the uncorrected digital template, since this time is needed for the calculation and the exchange.
  • Exemplary embodiment 2 - digital printing decorative plate A wood decor was produced on a digital panel printing system (working width 2070 mm, panel size 2070 x 2800 mm, speed 80 m/min, 8 mm HDF panels, white primed, CRYK water-based ink, inline primer application approx. 3 g/m2).
  • the wood decor has repeat dimensions of 2800 mm in length and 2070 mm in width.
  • the gap between the plates was 140 cm.
  • An ipac inline monitoring system was installed across the entire width (2070 mm) of the production plant.
  • a digital template of the decor was saved. During production, print measurement data is recorded and saved for each repeat, i.e. for each printed decor. The similarity index to the reference measurement data is calculated from this pressure measurement data.
  • the predetermined criterion was set at 94% before the start of production. So if the measure of the deviation falls below 94% in this case, a change of the digital template is preferable. A similarity index of 92% was calculated for the repeat 863 produced.
  • the measurement data showed that the deviations are essentially on the L axis > light-dark (eg 4% to dark). Since the deviation is above the specified tolerance, the measurement data is automatically transferred to the Colorgate software and a corrected digital template of the wood decor is calculated and saved. After automatic transfer to the output device, the print file (digital template) previously used for the print job was automatically replaced by the corrected digital template of the wood decor and made available as a print file for the following report. After the corrected digital template of the wood decor was issued, a similarity index of 96% was calculated from the first print measurement data.
  • the corrected data was printed in the following gap, since this time is needed for the calculation and the exchange. Thanks to the prompt, automated adjustment and replacement of the print data for the wood decor, production was able to meet the specifications of the similarity index again within a gap.
  • a wood decor was printed on paper using a digital paper printing system.
  • the working width was 2070 mm.
  • the speed was 135 m/min.
  • a white decorative paper with a basis weight of 65 g/m 2 and water-based CRYK ink and an inline primer application of approx. 3 g/m 2 were used.
  • the wood decor had repeat dimensions of 1400 mm in length and 2070 mm in width.
  • An ipac inline monitoring system was installed across the entire width (2070 mm) of the production plant.
  • a digital template of the decor was saved. During production, print measurement data is recorded and saved for each repeat, i.e. for each printed decor. The similarity index to the reference measurement data is calculated from this pressure measurement data.
  • the predetermined criterion was set at 95% before the start of production. So if the degree of deviation falls below 95% in this case, the digital template must be changed. A similarity index of 63% was calculated for the produced repeat 4.587. The measurement data showed that the deviation is essentially on the L axis > light-dark (e.g. 30% too dark). Since the deviation is above the specified tolerance, the measurement data is automatically transferred to the Colorgate software and a corrected digital template of the wood decor is calculated and saved. After automatic transmission to the output device, the print file (digital template) previously used for the print job is automatically replaced by the corrected digital template of the wood decor and made available as a print file for the following report. After the corrected digital template of the wood decor was issued, a similarity index of 75% was calculated from the first print measurement data. In this case, the reason for the discrepancy was that the wrong type of paper was printed. The software could not correct this strong deviation.
  • the production plant was stopped, the dryer was set lower and production continued.
  • Exemplary embodiment 4 digital printing decor plate - correction not possible - plate too cold - then signal
  • a wood decor was printed on a digital panel printing system (working width 2070 mm, panel size 2070 mm x 2800 mm, speed 80 m/min, HDF panels with a thickness of 8 mm, white primed, CRYK water-based ink, inline primer application approx. 3 g/m2). produced.
  • the wood decor has repeat dimensions of 2800 mm in length and 2070 mm in width.
  • the gap between the plates was 140 cm.
  • An ipac inline monitoring system was installed across the entire width (2070 mm) of the production plant. During production, print measurement data is recorded and saved for each repeat, i.e. for each printed decor. The similarity index to the reference measurement data is calculated from this pressure measurement data.
  • the predetermined criterion was set at 90% before the start of production. So if the degree of deviation is less than 90% in this case, a change in the digital template is preferable. A similarity index of 58% was calculated for the repeat 1123 produced. The measurement data showed that the deviation is essentially on the L axis > light-dark (e.g. 35% too dark). Since the deviation was above the specified tolerance, the measurement data was automatically transferred to Colorgate and a corrected digital template of the wood decor was calculated and saved. After automatic transmission to the output device, the print file (digital template) previously used for the print job is automatically replaced by the corrected digital template of the wood decor and made available as a print file for the following report.
  • a signal tone sounded which draws the machine operator's attention to the deviation and the production system stops automatically.
  • the machine operator can check and correct the parameters of the printing system and continue production.
  • the digital template on which the print is based is an important aspect when it comes to achieving the best possible print image that is true to the original and keeping the amount of waste produced as small as possible. Another aspect concerns, for example, the humidity of the surface to be printed.
  • a digital printing system is preferably used, the printing system having at least one application unit for applying a liquid to the workpiece and at least one dryer unit for drying the workpiece, and the method having the following steps:
  • Such a method enables the method to be carried out in an automated and reproducible manner, and thus the printing of the surface of a workpiece possible.
  • a large number of workpieces can also be produced identically or at least almost identically and with as little scrap as possible.
  • the electrical control which is an electronic data processing device, for example.
  • the electrical control determines drying parameters that contain or are in particular control parameters for the dryer unit. These drying parameters contain, for example, the dryer output, a dryer temperature, a transport speed at which the workpiece to be dried is moved through the dryer unit, and/or the type of dryer.
  • the last parameter is particularly advantageous when the dryer unit has different dryers that can be used as needed.
  • the dryer unit is operated with the drying parameters determined in this way in order to dry the respective workpiece.
  • the provision of information preferably includes the following steps:
  • the device that is used to carry out such a method has at least one moisture sensor that is set up to measure the moisture on the surface of the workpiece.
  • the at least one sensor is also set up to transmit the measured values that it determines to the electronic data processing device or to another type of electrical control.
  • the measured values allow conclusions to be drawn about the actual moisture content of the surface of the workpiece that is to be dried and is made available in the electrical control system as information about the expected moisture content.
  • the moisture is preferably determined as close as possible in front of the dryer unit, so that the measured values describe the moisture that the workpiece has when it enters the dryer unit as accurately as possible.
  • the transport speeds must speed with which the workpiece is transported to the dryer unit and the distance between the point at which the measurement is carried out and the start of drying must be coordinated in such a way that the electrical control, in particular the electronic data processing device, has sufficient time to determine the drying parameters to be determined before the workpiece to be dried is fed into the dryer. This distance depends on the one hand on the transport speed and on the other hand on the measurement data and the speed of the data processing device.
  • the moisture is preferably determined by means of an infrared (IR), near-infrared (NIR) or microwave measuring method and/or an L value determination.
  • IR infrared
  • NIR near-infrared
  • microwave measuring method microwave measuring method and/or an L value determination.
  • the combination of different methods is also possible and may be advantageous.
  • the choice of the actual method depends in particular on what information is required in order to be able to determine the drying parameters as optimally as possible. It can be advantageous to determine the moisture only in the narrowest possible area on the surface, for example down to a depth of 1 mm. In other methods, it is advantageous to also determine the moisture in deeper layers, for example down to a depth of 3 mm or 5 mm, and not just on the surface of the workpiece.
  • the moisture is preferably determined down to a depth of a few hundredths of a millimeter to a few tenths of a millimeter, for example from 0.01 mm to 0.5 mm.
  • the expected humidity is calculated. This is preferably done on the basis of information about at least one amount of liquid applied to the workpiece before drying, at least one temperature, preferably a temperature profile over time, in particular of the workpiece, the space and/or the liquid applied and/or the moisture content of the workpiece. If at least a quantity of liquid has been applied to the workpiece before drying, this will of course have a major influence on the moisture, especially on the top and surface of the workpiece workpiece.
  • the liquid that is applied can be, for example, a primer, an undercoat, ink or a protective layer.
  • the temperature of the workpiece, the room and/or the liquid applied has an influence on how much moisture, for example, the workpiece can absorb and/or how much moisture penetrates into the workpiece.
  • the information provided about the expected moisture and the determined drying parameters are each a function of the position on the surface of the workpiece.
  • both the expected humidity and the drying parameter are given as a function of location.
  • This is particularly advantageous when, for example, the expected moisture is distributed inhomogeneously over the surface of the workpiece. This can happen, for example, when printing ink is applied with different strengths, since, for example, some areas of the surface of the workpiece are printed more heavily and therefore with more ink than other areas.
  • the use of different inks, for example for different colors, can also lead to different amounts of moisture being applied to the surface of the workpiece and/or penetrating into the upper side of the workpiece.
  • An inhomogeneous amount of moisture can also result from the fact that the primer is applied to different degrees at different points on the upper side of the workpiece. This is the case, for example, if color fluctuations, for example cloudiness of the workpiece to be printed, for example a paper web, are to be compensated for by the primer, which was previously recorded and evaluated, for example by means of a camera. In this case, it makes sense to apply more primer to darker areas on the upper side of the workpiece to be printed than to lighter areas. This not only applies different amounts of primer, but also different levels of moisture.
  • the at least one dryer unit is advantageously set up to dry different areas of the surface of the workpiece to different extents.
  • the dryer unit can have, for example, a plurality of dryer modules, for example 3, 5 or 7 dryer modules, which are arranged in such a way that they dry different areas of the workpiece.
  • they can be arranged next to one another in a direction perpendicular to the transport direction of the workpiece through the printing system.
  • this arrangement not only allows inhomogeneous moisture distributions, which can prevail on the surface of the workpiece in front of the dryer unit, to be converted into homogeneous moisture.
  • the targeted generation of inhomogeneous moisture on the surface of the workpiece is also possible and can be advantageous.
  • the moisture on the surface of the workpiece influences how, for example, an ink or another applied liquid behaves on the surface. This can also be desired differently at different points, so that inhomogeneous moisture is an advantage.
  • target moisture distribution is preferably stored in an electronic data memory which the electrical control, in particular the electronic data processing device, of the printing system can access.
  • This setpoint moisture is preferably taken into account when determining the dryer parameters.
  • the workpiece is dried several times, which is advantageously done in different drying units.
  • the process steps a. and b. carried out i.e. information about the expected humidity is provided and drying parameters for the dryer unit are determined. These are transmitted to the dryer unit so that the dryer unit can be operated with them.
  • the workpiece is particularly preferably dried before and/or after at least one liquid is applied to the workpiece.
  • liquids are applied to the surface of the workpiece several times. This is preferably done in several commissioned works, for example rollers, print heads or others Order means can be.
  • the moisture applied in each case, possibly depending on the position on the surface of the workpiece, is stored in an electronic data memory and the electrical control is provided.
  • a primer can first be applied to the surface before different colored ink is applied, for example, in several print runs by several print heads, which represent the applied works.
  • the workpiece and in particular its surface are preferably dried.
  • the workpiece advantageously runs through a drying unit after each application.
  • a dryer unit is also particularly preferably passed through before the first application of a liquid and after the last application of a liquid.
  • the printing system therefore preferably has a plurality of application units, by means of which at least one liquid is applied to the workpiece, with the workpiece being dried before and/or after at least one liquid is applied.
  • the moisture on the surface of the workpiece is measured by means of at least one moisture sensor and compared with a predetermined target value, with a measure of the deviation of the measured moisture from the predetermined target value being included in the future determination of the drying parameters. It is therefore advantageous not only to determine the moisture on the surface of the workpiece before the actual drying in order to determine drying parameters, but also to measure the moisture again or for the first time after the actual drying. On the one hand, this can be used to check whether the target moisture content has been reached, i.e. whether the determined drying parameters are achieving the desired goal. If this is the case, there is no need to change the routines and settings in the electrical control system that determines the drying parameters.
  • the calculations used to determine the drying parameters are adjusted and modified in the electrical control.
  • the expected humidity for dryer units arranged later in the production process can also be better determined and thus better information can be made available to the electrical control system.
  • the future determination of drying parameters can relate both to drying parameters of dryer units used later, which are used when printing the same surface of the workpiece.
  • the future determination can also relate to drying parameters that are used when printing surfaces of other workpieces.
  • the workpiece is preferably a paper web and a degree of wrinkling of this paper web is recorded in the printing system. This is preferably done by means of a 2D and/or 3D profile measurement, which is particularly preferably carried out using a laser scanner.
  • the recorded degree of wrinkling is compared to a predetermined target value. If the deviation between the recorded dimension and this target value is greater than a predetermined limit value, the tension that is exerted on the workpiece in the printing system is changed. Depending on the deviation, the voltage is increased or decreased.
  • the invention also solves the problem set by a digital printing system for carrying out one of the methods described here, which has at least one application unit for applying a liquid to the workpiece and at least one dryer unit for drying the workpiece and an electrical controller, in particular an electronic data processing device. which is set up to carry out one of the methods described here.
  • Figure 1 the schematic representation of a sequence of a method according to a first embodiment of the present invention
  • FIG. 1 schematically shows the course of a method according to a first exemplary embodiment of the present invention.
  • a digital template 2 is provided, which is only shown schematically.
  • a decor is printed onto a print surface (not shown) using a digital printing system 4 .
  • Spatially resolved print measurement data 6 are determined from this printed decor, for example by measuring the printed decor with sensors that are not shown in FIG.
  • the pressure measurement data 6 are compared in a comparison module 10 with reference measurement data stored in an electronic data processing device 8 .
  • the extent of the deviation in the electronic data processing device 8 is determined on the basis of the result of this comparison.
  • a modified digital template 12 is determined in the electronic data processing device 8, which then replaces the previous digital template 2 in the printing system 4 in method step 14. If the change made to the digital template is sufficient, production is continued in accordance with the schematic representation 16 . Otherwise a signal 18 is output, which may stop production.
  • FIG. 2 schematically shows different print surfaces 20 that are printed along the direction of production indicated by the arrow 22 .
  • the printing surfaces 20 are thus printed in order from left to right. It should be noted that the actual transport direction within a printing plant is in the opposite direction.
  • the print measurement data are determined, the comparison with the reference measurement data is carried out and a measure for the deviation is determined. If this meets the predetermined criterion, a modified digital template is created and sent to the printing system. During these steps, the print surface 26 is printed. In the exemplary embodiment shown, the unchanged digital template that was also used for printing on the printing surface 24 is used. The changed digital template is only used for printing the print surface 28 .

Landscapes

  • Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • General Physics & Mathematics (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Wood Science & Technology (AREA)
  • Printing Methods (AREA)
  • Accessory Devices And Overall Control Thereof (AREA)
  • Ink Jet (AREA)

Abstract

L'invention concerne un procédé pour l'impression d'une décoration devant être imprimée sur une pluralité de surfaces d'impression au moyen d'un système d'impression numérique (4), le procédé comprenant les étapes suivantes : a. fournir un modèle numérique (2) et des données de mesure de référence hyperspectrales et spatialement résolues et d'une décoration devant être imprimée ; b. imprimer la décoration devant être imprimée sur une surface d'impression (20) à l'aide du modèle numérique (2) ; c. mesurer des variables mesurées de la décoration imprimée sur la surface d'impression (20) de telle sorte que des données de mesure d'impression hyperspectrales et spatialement résolues (6) soient obtenues ; d. comparer les données de mesure d'impression (6) aux données de mesure de référence et déterminer un degré d'écart des données de mesure d'impression (6) par rapport aux données de mesure de référence ; e. modifier le modèle numérique (2) si le degré d'écart satisfait un critère prédéfini ; f. répéter les étapes b. à f..
EP21766160.2A 2020-08-24 2021-08-24 Procédé pour l'impression d'une décoration, et appareil pour celui-ci Pending EP4200584A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP20192453.7A EP3961166A1 (fr) 2020-08-24 2020-08-24 Procédé d'impression d'un décor et dispositif correspondant
PCT/EP2021/073357 WO2022043309A1 (fr) 2020-08-24 2021-08-24 Procédé pour l'impression d'une décoration, et appareil pour celui-ci

Publications (1)

Publication Number Publication Date
EP4200584A1 true EP4200584A1 (fr) 2023-06-28

Family

ID=72234749

Family Applications (2)

Application Number Title Priority Date Filing Date
EP20192453.7A Pending EP3961166A1 (fr) 2020-08-24 2020-08-24 Procédé d'impression d'un décor et dispositif correspondant
EP21766160.2A Pending EP4200584A1 (fr) 2020-08-24 2021-08-24 Procédé pour l'impression d'une décoration, et appareil pour celui-ci

Family Applications Before (1)

Application Number Title Priority Date Filing Date
EP20192453.7A Pending EP3961166A1 (fr) 2020-08-24 2020-08-24 Procédé d'impression d'un décor et dispositif correspondant

Country Status (5)

Country Link
US (1) US20230322008A1 (fr)
EP (2) EP3961166A1 (fr)
CN (1) CN115997108A (fr)
CA (1) CA3190020A1 (fr)
WO (1) WO2022043309A1 (fr)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
PL4016980T3 (pl) * 2020-12-21 2024-02-26 SWISS KRONO Tec AG Sposób i urządzenie do zadrukowywania wstęgi papieru
EP4068743A1 (fr) * 2021-03-30 2022-10-05 SWISS KRONO Tec AG Procédé d'ajustement des paramètres d'imprimante d'une imprimante numérique
EP4258637A1 (fr) * 2022-04-08 2023-10-11 SWISS KRONO Tec AG Procédé d'impression d'une bande en papier

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT504213B1 (de) * 2006-09-22 2008-04-15 Ipac Improve Process Analytics Verfahren zum ähnlichkeitsvergleich von gegenständen
SI3578939T1 (sl) 2018-06-06 2021-02-26 Flooring Technologies Ltd. Postopek spletne kontrole kakovosti dekorskih tiskov na nosilnih materialih
EP3867079A1 (fr) 2018-10-17 2021-08-25 Agfa Nv Procédé de fabrication de panneaux décoratifs par correction chromatique

Also Published As

Publication number Publication date
WO2022043309A1 (fr) 2022-03-03
CA3190020A1 (fr) 2022-03-03
EP3961166A1 (fr) 2022-03-02
US20230322008A1 (en) 2023-10-12
CN115997108A (zh) 2023-04-21

Similar Documents

Publication Publication Date Title
EP4200584A1 (fr) Procédé pour l'impression d'une décoration, et appareil pour celui-ci
EP3006216B1 (fr) Procede de compensation de defauts de reperage locaux
WO2015028166A1 (fr) Procédé et dispositif de production d'un matériau de départ pour pneus de véhicules
EP3896953B1 (fr) Procédé de commande d'un processus d'impression décorative
EP1759844B2 (fr) Procédé pour corriger l'impression
EP3415317A1 (fr) Procédé et dispositif de fabrication d'une surface décorative
EP3013589B1 (fr) Installation de fabrication de plaques en matériau dérivé du bois et procédé de fabrication d'une plaque en matériau dérivé du bois
WO2018046390A1 (fr) Presse à chaud pour panneau de matériau dérivé du bois et son procédé de fonctionnement
DE3614555A1 (de) Verfahren und anordnungen zur einstellung des einsatzzeitpunktes der seitlichen verreibung fuer druckmaschinen
EP3960479B1 (fr) Procédé d'impression de la surface d'une pièce dotée d'un décor et dispositif correspondant
EP3525953B1 (fr) Procédé d'ajustage d'un outil de formage à l'aide d'une matière de dressage
EP3943241A1 (fr) Procédé de ponçage d'une surface d'une pièce et dispositif correspondant
DE102010060950B4 (de) Verfahren zum Kalibrieren einer Druckvorrichtung
EP4008561A1 (fr) Procédé et dispositif d'impression d'une surface d'un papier
DE4436582A1 (de) Verfahren und Vorrichtung für die Schmiergrenzenerkennung und Feuchtmittelführung in einer Offsetdruckmaschine
EP3757508B1 (fr) Procédé de détermination de la quantité d'une couche appliquée sur une plaque porteuse, en particulier une couche d'apprêt
EP4108472A1 (fr) Procédé d'usinage du papier décoratif
EP4272967A1 (fr) Procédé d'impression sur un substrat et imprimante numérique comprenant des moyens pour réduire la formation de condensation
EP4068743A1 (fr) Procédé d'ajustement des paramètres d'imprimante d'une imprimante numérique
DE10147392B4 (de) Verfahren zum zonenweisen Bedrucken einer Bedruckbahn
EP4272966A1 (fr) Procédé d'impression sur un papier et imprimante numérique comprenant des moyens pour réduire la formation de condensation
WO2022112173A1 (fr) Procédé de création et de comparaison de profils de couleur
DE102021104951A1 (de) Inline Deckweißregelung
DD277525A1 (de) Verfahren und einrichtung zur kontinuierlichen regelung des trocknungsprozesses bei der pappherstellung und dgl. prozessen

Legal Events

Date Code Title Description
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: UNKNOWN

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE

PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20230220

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

DAV Request for validation of the european patent (deleted)
DAX Request for extension of the european patent (deleted)