DE102007007626A1 - Method for monitoring of printing parameter of printing machine, involves printing test chart by printing machine and scanning of printed test chart by spectrophotometer - Google Patents

Abstract

The method involves printing a test chart (4) by a printing machine (1). The printed test chart is scanned by a spectrophotometer (6) for receiving of spectral values which contain information over the quality of the printing parameters. The spectral values received in a data bank (10) are stored in non volatile manner6. The spectral values stored in the data bank are read by a computer unit (11). An independent claim is also included for a device for monitoring of printing parameter of a printing machine.

Description

The The invention relates to a method and a device for monitoring the print parameter of a printing press.

It is already known to detect the acting in a printing process Variables the operation of the printing device for one longer period of interruption and within this Period to print a variety of test charts, respectively have a plurality of control fields and control images. These printed test charts are subject of a person under subjective Assessment points to statements about the printing process to receive acting variables. In addition, density measurements and spectral measurements performed. Within the scope of all the above Investigations will ultimately be checked to see if the results obtained are in given ranges.

The The measurements described above are made in compliance with DIN standard 16614, which states inter alia that spectral measurements must be made without using a polarizing filter.

disadvantage The procedure described above consist on the one hand in the subjectivity of the evaluation of the test charts and the others in that the spectral measurements made without using of a polarizing filter are made, not correct and error-prone results.

From the DE 10 2004 044 763 A1 For example, a measuring field arrangement and a method for detecting variables acting in a printing operation are known. The measuring fields of the measuring field arrangement are in the form of a measuring field block with several rows and several columns. A first group of measuring fields is used to record the tonal behavior, a second group of measuring fields to detect gray-axis behavior, and a third group of measuring fields to record the printing behavior in the case of overprinting. Such a measuring field arrangement is printed on a printed sheet in the form of a test chart from a printing machine to be tested or a printing device to be tested. The individual measurement fields of the test chart are scanned by means of a spectrophotometer, which is preceded by a polarization filter. From the obtained measurement data, which are spectral values, tables and / or graphics are determined by an evaluation unit, which provide information about the Tonwertverhalten, the gray-axis behavior and the printing behavior of the overprinting. The results obtained can be used to optimize the printing process by manual settings on the printing device or the printing press. They can also be used to control the printing parameters, with this control taking place using a control unit of the printing device or the printing machine, to which the obtained measuring results are transmitted in the form of spectral values. As part of the evaluation of the measurement results, a comparison of the measured values obtained with predetermined reference values can be made. Furthermore, in the context of the evaluation of the measurement results, these measurement results can be linked together or compared with one another. This reconciliation provides detailed information about the results obtained and allows a faster and more accurate analysis of the causes of errors that have occurred.

The The object of the invention is the functionality of the known method and the known device to expand.

These The object is achieved by a method with the specified in claim 1 Characteristics and by a device with the specified in claim 15 Characteristics solved. Advantageous embodiments and developments The invention are defined in the dependent claims specified.

The Advantages of the invention are that of the spectrophotometer output spectral values due to their non-volatile Storage in a database also at later times for evaluation by a computer unit based on the data stored in the database can be accessed stand. This evaluation can serve statistical purposes. The Results of the evaluation can also be used for a regulation the printing press can be used on the control console.

The database advantageously has storage capacity for a multiplicity of spectral value data sets, so that, among other things, spectral values which belong to different data sets can be compared with one another. This allows, for example, a monitoring of the printing parameters of the printing press over a long period. Slow changes in the pressure parameters can be applied to the be made visible manner and it can be remedied by manual intervention on the press or in the sense of a control process.

The Spectral values records are advantageously each linked to production data when stored. For example, this production data refers to a specific one Order and include information about the associated Order Number, the type of paper used in this order, the used measuring method, the measuring geometry used, a verwen detes Measuring device and / or machine data. They become, for example from the order processing computer of the respective printing company to the Database and are associated with this order Assigned to spectral values.

One Advantage of this approach is that in a simple manner Repeat orders can be executed. In such repetition orders are already in stored in the database, the original order associated spectral values as a reference for the Repeat order.

In The database is also advantageously a proof chart assigned spectral values record stored. This one will compared to a spectral values record, which is on the sample a printed from the printing machine test chart is based. The Comparison result gives information about whether by means of existing printing press achievable a print quality which corresponds to the proof chart.

A simple embodiment of the invention is that determined by the computer unit comparison result in color Form on a display. For example, differs from the Test chart associated spectral values record only slightly from the record used as a reference, then becomes a traffic light displayed with green light. But exist between the Testchart associated spectral values record and as Reference used spectral values record larger Deviations, then a traffic light is displayed with red light. In this the latter case, the press is currently unable to a desired print job in a given quality perform. It requires at least one cleaning or Maintenance of the printing press. Optionally, also by means of existing printing press a print quality like one predetermined Proofchart, not to be achieved.

The Computer unit, which is stored in the database data accesses and evaluates this, can as result data also control signals provide that fed to the control room of the printing press become. This can be information about the density the inks or information about when printing existing or needed for printing Act water volumes.

A preferred embodiment of the invention is by means of the computer unit using in the database stored spectral values records an existing ICC profile to modify or readjust. The modified one ICC profile associated data is from the computer unit fed to the raster pulse processor of the printing press and stored there instead of a previously stored ICC profile.

Of Furthermore, in the database also virtual are advantageously Reference data saved non-volatile. These will by means of an input unit, for example a keyboard. The virtual reference data correspond to LAB values that are a DIN standard or an ISO certification, for example LAB values for the colors cyan, magenta, yellow and black, and pressure point growth values in percent. These values are from the computer unit evaluated to check whether the present printing press the determination of the respective DIN standard or the requirements of an ISO certification.

Of Furthermore, in the database also advantageously the computer unit determined error data non-volatile stored. This allows a statistical evaluation of the Printing error occurred. Preferably, in the database also stored solution-relevant data, which are addressable by the error data. this makes possible it, for example, in the case of the occurrence of a fault of the operator display on a display in alphanumeric or graphic form, What measures must he take to the occurred Eliminate errors. Alternatively, there is also the option to transmit control signals to the control station, which are transmitted by the Control center in positioning commands for the components of the printing machine be converted, so that an error occurred automatically is turned off.

Further advantageous features of the invention will become apparent from the exemplification thereof based on the figures. It shows

1 a block diagram of a device for monitoring the printing parameters of a printing machine,

2 a sketch of a measuring field arrangement, as used in the invention, and

3 a diagram illustrating the allocation of the memory areas of the database.

The illustrated device has a printing machine 1 on, whose operation of a control station 2 is controlled. By means of this printing machine, a printed sheet is printed for the purpose of monitoring the printing parameters, on which a test chart 4 is applied.

As a test chart is preferably in the DE 10 2004 044 763 A1 used test chart described. This test chart is in the 2 shown. It has a total of 168 measuring fields, which are in the form of a measuring field block with four rows and 42 columns.

The Lines of the pad block are with the numbers 1, 2, 3, 4 and the Columns of the measuring field block with the letters A, ..., Z and 2A, ..., 2P. This measuring field arrangement is designed such that the most important in a printing process by means of a printing press or a pressure device acting variables are detected can and continue to show their interaction can be. In particular, such a measuring field arrangement allows a recording of the Tonwertverhaltens, a detection of gray-axis behavior and a recording of the printing behavior in overprinting. The results obtained may be in the form of tables and / or in the form of graphical representations. This allows for example, a comparison between a printed and a gray axis calculated in advance as a reference. It also allows this For example, an assessment of the trapping behavior.

To obtain these results, all the measuring fields of the measuring field arrangement by means of a spectrophotometer 6 sampled, which is a polarizing filter 5 upstream. The spectrophotometer 6 output spectral values become an evaluation unit 7 fed, which determines the desired result data from the spectral values by simple arithmetic, comparison and sorting operations and by means of an output unit 8th outputs. For example, this output unit is a display.

Each measuring field of the 2 has a special task, as explained below.

The Fields B4, N3 and 2P4 have cyan, magenta, yellow and black values, each 0%, and a brightness value that is 100% lies.

These Fields represent the paper white and show Pollution caused by an unclean pressure were. This is especially true with toner and inkjet based Systems. Should the ones obtained with respect to these fields Measured values do not correspond to the values of paper white, so an optical control of the existing printing machine is to make to detect the cause of this error and eliminate the error to be able to. In offset printing machines can impurities of this kind are caused by toning.

The The following tables 1-4 provide information on the Measurement fields used to evaluate the tonal behavior of the primary colors are provided.

From these Tables 1-4 it can be seen that for each of the tonal values cyan, magenta, yellow and black a plurality of measuring fields is provided. The numbers given in the tables indicate that the respective measuring field is printed with the respective color and that, ideally, the respective field should have a measured area coverage that corresponds to the percentage indicated in the table. By scanning the respective field by means of the spectrophotometer 6 to which the polarizing filter 5 upstream, measured values are obtained which show possible deviations from the said ideal case and thereby provide information about the tonal behavior of the individual colors.

The Measured values derived from these measurement fields are preferably both in the form of a table and in graphical form.

According to one Embodiment, the obtained measured values are given with Reference values compared. If deviations occur, then you can Operator inputs or settings or in terms of a scheme a desired setting of the printing machine brought about become.

The If necessary, reference values may be given with regard to possible customer requests are modified. Also one Aligning the reference values with valid standards or specific ones Printing process can be performed easily.

To the gray axis behavior of the printing press 1 The fields shown in the following table are measured: Table 5: Measuring fields for recording gray-axis behavior in printing name of field cyan magenta Yellow Black Q2 4 3 3 0 2A2 6 4 4 0 2L4 8th 5 6 0 D2 11 8th 8th 0 I2 15 11 11 0 2H2 19 14 14 0 2K2 23 17 17 0 T1 27 20 20 0 2D3 31 23 22 0 M3 35 25 25 0 K4 39 29 29 0 2N3 44 32 32 0 A3 48 36 36 2 E2 52 39 39 5 G4 55 51 51 8th T3 58 44 44 12 X1 62 47 47 17 2A1 64 50 50 23 2M4 68 52 52 31 Q1 71 55 54 39 L2 74 56 56 49 o2 78 59 59 62 2K3 82 66 65 77 U1 94 83 78 90

The measured values obtained with respect to these fields by means of the spectrophotometer are, for example, from the evaluation unit 7 translated into a graphic. In this graphical representation, the measured values are combined with calculated optimum values and deviations from the desired pressure behavior are shown in this way. If the deviations exceed given tolerances, the press and the standardization should be checked.

The output of the obtained measured values can also be in the form of one of the evaluation unit 7 created table.

Possibly The output of readings may also be along with Delta E deviations respectively. Delta E is the arithmetic mean of the three CIE-L * a * b * values of two or more measured values. In the CIE (Comission Internationale de l'Eclerage) is concerned a commission, through empirical studies with students examined the color vision and determined a CIE color space.

By means of in the 2 illustrated measuring field arrangement can also be made an analysis of the printing behavior in the light area. The results of this evaluation show the behavior of the printing inks with a small layer thickness. This evaluation is important for the assessment of the ink acceptance behavior on the respective substrate.

The results of the associated measurement data evaluation can be graphically as well as in form ei ner table are shown. The output of the measured values in the table takes place in the form of CIE-L * a * b * values.

The Results of this evaluation are only due to the press calibration, the substrate, the ink used, the blanket used or to influence the used printing plate or its calibration. The printed density (100% area) has only a small amount Influence on the result of the measurement.

By an evaluation of that given in Tables 6, 7 and 8 below Fields can be the properties of the in or overprint Evaluate the resulting secondary colors. Occurring deviations in the color balance indicate a misconduct in the print out.

Deviations in printed final density as well as problems with trapping can be the cause of deviations in value. Table 6: Measuring fields cyan-magenta name of field cyan magenta Yellow Black 2L3 10 10 - - 2L2 20 20 - - E1 40 40 - - H1 60 60 - - 2N1 80 80 - - Z2 100 100 - - Table 7: Measuring fields cyan-yellow name of field cyan magenta Yellow Black 2I1 10 - 10 - H2 20 - 20 - I1 40 - 40 - 2K4 60 - 60 - D3 80 - 80 - 2H3 100 - 100 - Table 8: Measuring fields magenta-yellow name of field cyan magenta Yellow Black U2 - 10 10 - 2G4 - 20 20 - P4 - 40 40 - A4 - 60 60 - T2 - 80 80 - 2C4 - 100 100 -

The The fields given in Tables 6, 7 and 8 show the acceptance behavior when overprinting two colors. Become metrologically those spectral deviations recorded when overprinting of grid surfaces can arise. A tabular The measured values obtained are reported using CIE-L * a * b * values and an indication of the mean deviation Delta-E.

By evaluating the fields given in Table 9, information is obtained about the ink acceptance behavior when overprinting three colors. Also in this case, spectral deviations are determined by a misconduct in the overprint. The values are recorded and output in CIE-L * a * b * mode. The mean deviation is indicated by Delta-E. Table 9: C, M, Y in combination name of field cyan magenta Yellow Black 2D4 10 10 10 - 2D1 15 15 15 - A1 20 20 20 H3 25 25 25 - 2L1 30 30 30 - 2H4 35 35 35 - Z3 40 40 40 - 2D2 45 45 45 - 2P3 50 50 50 - 2H1 55 55 55 - L1 60 60 60 - o3 65 65 65 - P3 70 70 70 - 2E1 75 75 75 - U3 80 80 80 - Z4 85 85 85 - M4 90 90 90 - H4 95 95 95 - D4 100 100 100 -

The properties of the compression affect the gray-axis behavior. In order to be able to assess this gray-axis behavior more accurately, the measurements given in Table 9 are Fields derived results associated with the gray axis behavior and the already determined pressure characteristic in combination.

different Compressive properties of two or three colors will be caused by different process variables. Only one evaluation the results from all the fields allows an accurate and correct assessment of the measured values.

From the following Table 10 shows how conclusions can be drawn on the printing behavior of the colors in the range of lights by an evaluation of the se-tenant specified therein and in how far the paper white influences the optical effect. These fields are used in particular for the evaluation of proof matching. A proof is a color-consistent pattern for visually inspecting color images for parties involved in printing and, where appropriate, for customers. Table 10: C, M, Y, K in combination name of field cyan magenta Yellow Black 2O4 2 2 2 2 2P1 4 4 4 4 2M3 5 5 5 5 2P2 6 6 6 6

By an evaluation of the derived from these fields measured values Draw conclusions about the ink acceptance behavior when overprinting four colors. Also here Spectral deviations are caused by a misprint in the overprint detected. The recording of the values and their output takes place in CIE-L * a * b * mode. The mean deviation is indicated by Delta-E.

Based The measurement results described above can be individually Derive information about all relevant print parameters, which are recorded on the sheet using the measuring method presented here can. To the expressiveness of the obtained measured values increase, a comparison of the measurement results. This Matching the individual measurement results allows more detailed Statements about the results obtained. Likewise possible such a data comparison a more accurate and faster analysis of occurring errors or a more accurate and faster detection the cause of occurring errors.

So For example, a comparison of the measurements of the tone curve and gray-axis behavior. The gray axis values will be on it Toning behavior checked out. The from this Testing resulting values will match the values the already established tone curve is related. Occurring deviations shall be accompanied by appropriate information on the extent of specified misconduct indicated.

Has been determined in advance a gray-axis shift, then it is checked whether in one or more of the printed colors the tonal behavior is outside the specifications or whether the tonal tolerances take full advantage of a permissible range.

Based This example makes it clear that a statement about the pressure behavior is conclusive only when the obtained Measurement results are related to each other.

A further possibility of a comparison of received measurement results consists of both the gray-axis behavior and the tonal behavior to relate to a combination of the individual colors. The results resulting from such a comparison show on the one hand, how far the gray-axis behavior is due to the overprinting on the other hand, in how far the tonal behavior changes by the overprint.

In the next step, these two results are related to each other. The result of this relationship provides information about the color balance of the print. The color balance shows the interaction between the ink acceptance behavior and the gray-axis stability on the one hand and the tonal behavior and the ink acceptance behavior on the other side.

• – eine Auskunft darüber, welcher der beiden Faktoren die optische Anmutung des Druckes prägt und
• – eine Auskunft darüber, ob die Bilder durch den Druck in ihrer optischen Anmutung verändert werden bzw. ob diese Veränderung durch den Druckprozess noch innerhalb vorgegebener Toleranzen liegt.

The above-mentioned factors tone behavior and gray-axis behavior have a significant influence on the visual effect of the image to be printed. However, the nature of the optical change is fundamentally different. In order to be able to assess the balance, spectral values from the two aforementioned results are offset against one another, namely the logarithmic density of the four-color printed fields in comparison to the three-color, two-color and monochrome printed fields. From this calculation, the following two results are derived:

• - An information about which of the two factors characterizes the visual appearance of the print and
• - An indication of whether the images are changed by the print in their visual appearance or whether this change by the printing process is still within specified tolerances.

in the The scope of the procedure described above is after all by means of the printing machine to be tested or to be tested Printing device printed a test chart on a sheet. The test chart relates to a predetermined measuring field arrangement to the used measuring device. The individual measuring fields of the measuring chart are determined by means of the measuring device, namely a spectrophotometer, sampled, which has a polarizing filter upstream. An evaluation of the obtained measured values provides information about the most important variables in a printing process. To the tonal behavior, the gray-axis behavior, the printing behavior in the area of light, the printing behavior in the case of overprinting of two colors, the printing behavior in a overprint of three colors and the printing behavior in a overprint of four colors. The use of the polarizing filter has the Advantage of a mapping of the entire color space.

The spectrophotometer used works according to the following specifications or settings: - Illumination geometry: 45 ° / 0 ° with circular illumination; - standard light D50; - normal observer: 2 °; and - white cover: absolutely.

Around to ensure the reliability of the measurement results obtained Care should be taken during the measurements always the same ambient conditions prevail. Farther Care should be taken that a regular Control of the measuring means takes place. In case that Reference prints are created, make sure that these packed in a light-tight package at maximum room temperature.

Around the informative value of the obtained measurement results in the form of Tables and / or graphics are output to increase the obtained measurement results are linked together or compared with each other. This adjustment allows more detailed statements about the results obtained. Likewise, this comparison allows a faster and more accurate Analysis of causes of errors.

The functionality described above is in the in the 1 shown device extended by that at the output of the spectrophotometer 6 provided and a first test chart 4 associated measurement data, which are in the form of spectral values, via a database interface 9 into a database 10 enrolled and become non-volatile there. The from the test chart 4 derived spectral values correspond to a spectral values record.

To the database 10 is a computer unit 11 connected to the in the database 10 non-volatile stored spectral values have access and these spectral values long after their storage in the database 10 for the purpose of evaluation.

An evaluation option is, except the test chart 4 also a proof chart 3 by means of the spectrophotometer 6 to which a polarizing filter 5 is upstream of sampling and the Proofchart associated spectral values also in the form of a spectral values record in the database 10 save non-volatile. The computer unit 11 then compares the stored in the database, the test chart 4 associated spectral values with the stored in the database, the proof chart 3 associated spectral values to determine if the print engine achieves a print quality that matches the quality of the proof.

This is the case if the spectral values associated with the test chart are only slightly different from those of the the proof chart 3 deviate from the corresponding spectral values. In this case, the computer unit sets 11 at its output a positive result signal ready, for example, a green signal on a traffic light on the display of an output unit 12 is pictured. Based on this green signal an operator recognizes that by means of the printing press 1 a print quality is achievable, which corresponds to the Proofchart. An existing job, which consists in printing with the print proof of corresponding print quality, can therefore be accepted or started.

On the other hand, those who steer clear of the test chart 4 associated spectral values significantly from the proof chart 3 associated spectral values, then puts the computer unit 11 at its output a negative result signal ready, for example, a red signal on the traffic light on the display of the output unit 12 is pictured. On the basis of this red signal an operator recognizes that by means of the printing press 1 currently a print quality that meets the proof chart, is not achievable. Accordingly, an existing job, which is to print with the proof sheet of appropriate print quality, can not be performed by the printing press at present. It requires at least a cleaning or maintenance of the printing press. Optionally, even after the cleaning or maintenance, the printing machine is not able to produce prints with a print quality corresponding to the proof chart. In the context of a comparison process carried out after cleaning or maintenance, this can be recognized by spectral values corresponding to the proof chart with the spectral values corresponding to a new test chart.

Another evaluation option is one in the database 10 stored Spektralwerte- data set, which is based on a test chart to associate production data to evaluate this spectral values record at a later date, for example, in the context of a repeat order.

The production data mentioned are, for example, from the order processing computer 14 provided to the printer, in which all of the print jobs to be performed by the printer are recorded and provided with associated production data. This production data preferably includes information about an order number, the type of paper to be used in this order, a measurement method used in that order, a measurement geometry used in that order, a measurement device used in that order, and / or data of the printing press used.

These production data associated with a particular order are processed by the order processing computer 14 which with the database 10 connected to the database and also in the database 10 stored. You are in the context of this order determined by a test chart and in the database 10 stored spectral values record assigned.

If a repeat job is to be carried out at a later time, then a new spectral data record is first determined by means of a new test chart and stored in the database 10 stored. Subsequently, the computer unit accesses 11 on the spectral value data set corresponding to the original order and the spectral value data set corresponding to the new test chart, and compares the spectral values of these data sets with one another.

If the spectral values corresponding to the new test chart deviate only slightly from the spectral values associated with the original task, then the computer unit provides 11 at its output a positive result signal ready, for example, a green signal on the traffic light on the display of the output unit 12 is pictured. Based on this green signal an operator recognizes that by means of the printing press 1 the print quality corresponding to the original job is achievable. The repeat order can therefore be accepted or started.

On the other hand, if the spectral values corresponding to the new test chart deviate considerably from the spectral values associated with the original order, then the computer unit provides 11 at its output a negative result signal ready, for example, a red signal on the traffic light on the display of the output unit 12 is pictured. On the basis of this red signal an operator recognizes that by means of the printing press 1 currently a print quality that matches the original test chart, is not achievable. It first requires a cleaning or maintenance of the printing press 1 before the repeat job can be started.

Alternatively or in addition to a representation of the computer unit 11 determined result signal on the display of the display unit 12 the said result signal can also be sent by means of a printer be printed out.

Another embodiment of the invention is that of the computer unit 11 to provide detected result signals in the form of control signals and via the control line 15 the control room 2 the printing press 1 supply. These control signals are from the control center 2 in positioning commands for the components of the printing press 1 implemented and then fed to these components. This procedure makes it possible to detect pressure parameter changes that occur during long-term operation of the printing press and to counteract them in the sense of a control process. Such printing parameters, which can change in the Langzeitbe operation of the printing press and can be corrected by such a scheme, for example, the density of the printing inks and the amount of water required in the printing process.

Another embodiment of the invention is in the database 10 stored spectral value data sets for readjusting or modifying ICC profiles. An ICC profile is a color profile which is in the form of a standardized data set describing the color space of a color input or color reproduction device. The data corresponding to such an ICC profile are generated by means of a known software program and in the form of a file in the raster pulse processor of the platesetter of the printing press 1 deposited. Such a standardized data record is used for color management, which is the existing device, for example the printing press 1 to enable it to reproduce a template as colourfast as possible. Colors that the press might not be able to display are shifted so that they are as close as possible to the original.

The in the database 10 stored spectral data records allow one for the present printing machine 1 modify the present ICC profile in the sense of a retro-linearization. The file corresponding to the linearized ICC profile is read by the computer unit 11 from there to the raster pulse processor of the platesetter of the printing press 1 transferred and stored in the raster pulse processor instead of the previously stored file.

This procedure corresponds to a determination of color space changes through the use of in the database 10 stored spectral data records. This determination of color space changes can be done quickly and quickly. Such a re-linearization of ICC profiles is particularly advantageous in the presence of digital printing in an RGB workflow. It leads to a more stable print run or a more stable pressure. Other applications are ICC profiles for offset printing and absolute colorimetric ICC profiles for color simulations.

Another embodiment of the invention is in the database 10 save virtual reference data non-volatile. These virtual reference data are in the embodiment shown by means of a keyboard 13 created and in the database 10 deposited non-volatile. These are reference data associated with an ISO certification, which are available in the form of so-called LAB values. On this in the database 10 stored LAB values, the computer unit 11 access. The computer unit 11 uses this data to convert these data into spectral values and then to compare the spectral values determined from the LAB values with spectral values associated with a test chart. The result of this comparison provides a statement as to whether the present printing press 1 meets the requirements of the said ISO certification or not.

In addition, in the database 10 advantageously also stored error data. These error data are, in particular, error data received from the computer unit 11 were determined during their evaluation of the stored in the database spectral values data sets. This error data can, depending on the individual case present on the display of the display unit 12 represented by a printer printed by the computer unit 11 in control signals for the printing press 1 implemented and / or in the database 10 be stored. Preferably, in the database 10 Also stored solution corresponding data that can be addressed by means of the error data.

If a certain error occurs, then this error is from the computer unit 11 by an evaluation of one or more of the in the database 10 stored spectral values records detected. The computer unit 11 generates a result signal associated with the detected error. This will be used to address the database 10 used. At the addressed address of the database corresponding data are stored a solution proposal for the detected error. These are taken from the database 10 read out and on the display of the display unit 12 shown.

If, for example, the tonal values of the primary colors lie in given ranges, they give way gray-axis behavior from expected values, then the values of the secondary and tertiary colors are checked. If deviations occur in one of the associated curves or measured values, then there is a problem with the trapping. This is the user on the display of the display unit 12 signaled.

Misbehavior in trapping can be caused by various causes. These are displayed according to their probability on the display unit 12 so that the user can selectively check the most common causes one at a time and eliminate them as needed.

When Additional help can be stored in the database Measurements fall back to earlier times were determined under comparable conditions.

Has been for example, the same paper type on the same day for used a different print job and performed it Measurements show other peculiarities, so the paper can be a source of error be excluded.

After all, according to the present invention, to the output of the spectrophotometer 7 a database 10 connected, in which a plurality of test charts associated spectral value data sets is preferably non-volatile stored together with associated production data. In addition, the database is used 10 also for the non-volatile storage of further data. These include, in particular, proof values associated spectral value data sets, data records corresponding to ICC profiles, data records corresponding to virtual reference data, data records corresponding to error data, and data records corresponding to proposed solutions. On all in the database 10 stored data has the computer unit 11 Access. It uses this data for a variety of different evaluations to the printing parameters of the printing press 1 to monitor. The from the computer unit 11 determined result data are either printed out, displayed on a display or supplied to the control center of the printing press to perform a regulation of the printing parameters.

The 3 shows a diagram illustrating the occupancy of the memory areas of the database 10 , The illustrated database 10 has storage areas 10a . 10b . 10c . 10d . 10e and 10f on. The storage area 10a For non-volatile storage of test chart spectral data sets and associated production data, is the memory area 10b for non-volatile storage of proof charts associated spectral value data sets, the memory area 10c for non-volatile storage of ICC profiles associated records, the memory area 10d for non-volatile storage of reference data corresponding records, the memory area 10e for the non-volatile storage of error data corresponding records and the memory area 10f provided for the non-volatile storage of proposed solutions corresponding records.

In the in the 1 The embodiment shown is the spectrophotometer 6 a polarizing filter 5 upstream. The use of a polarizing filter leads to more accurate and plausible measurement results. However, the method described can also be used without the use of a polarizing filter, if a larger tolerance range of the measurements is accepted.

1

Printing press printing device

2

control station

3

Proof chart

4

testchart

5

polarizing filter

6

spectrophotometer

7

evaluation

8th

output unit

9

Database Interface

10

Database

11

computer unit

12

output unit

13

input unit

14

Order processing unit

15

control line

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• DE 102004044763 A1 [0005, 0023]

Claims (28)

Method for monitoring the printing parameters of a printing machine, comprising the following steps: printing out a first test chart ( 4 ) by means of the printing machine ( 1 ), - scanning the printed first test chart by means of a spectrophotometer ( 6 ) for obtaining spectral values which contain information about the quality of the printing parameters, - non-volatile storage of the obtained spectral values in a database ( 10 ), - readout of spectral values stored in the database by means of a computer unit ( 11 ), - evaluation of the read out spectral values to obtain result data and - output of the result data. Method according to Claim 1, characterized in that the result data are printed out by means of a printer or displayed on a display ( 12 ) being represented. Method according to claim 1 or 2, characterized in that by means of the spectrophotometer ( 6 ) a proof chart ( 3 ), the spectral values associated with the proof chart are also non-volatile in the database ( 10 ) are stored in the computer unit ( 11 ) a comparison of the first test chart ( 4 ) spectral values with the proof chart ( 3 ) associated spectral values and the computer unit ( 11 ) outputs a result signal dependent on the degree of coincidence of the spectral values compared with one another. Method according to claim 1 or 2, characterized in that by means of the spectrophotometer ( 6 ) a second one from the printing machine ( 1 ) printed test chart ( 4 ), the spectral values associated with the second test chart are non-volatile in the database ( 10 ) are stored in the computer unit ( 11 ) a comparison of spectral values associated with the second test chart with spectral values associated with the first test chart takes place and the computer unit ( 11 ) outputs a result signal dependent on the degree of coincidence of the spectral values compared with one another. Method according to one of the preceding claims, characterized in that the result data are control signals and these control signals via a control line ( 15 ) the control desk ( 2 ) of the printing machine ( 1 ). Method according to claim 5, characterized in that the control signals contain information about the density of the printing inks and / or those of the printing press ( 1 ) contain required amount of water. Method according to claim 1, characterized in that the result data corresponds to a modified ICC profile and in the frame pulse processor of the printing machine instead of a hitherto stored ICC profile stored there. Method according to one of the preceding claims, characterized in that in the database ( 10 ) a non-volatile production data belonging to a set of stored spectral values. Method according to claim 8, characterized in that that the production data contains information about an order number, a paper type, a measuring method, a measuring geometry, a measuring device and / or machine data. A method according to claim 8 or 9, characterized in that the production data from an order processing computer ( 14 ) are provided to a printing company. Method according to one of the preceding claims, characterized in that in the database ( 10 ) virtual reference data are stored non-volatile. A method according to claim 11, characterized in that the virtual reference data by means of an input unit ( 13 ). Method according to one of the preceding claims, characterized in that in the database ( 10 ) Error data are stored non-volatile. Method according to claim 13, characterized in that in the database ( 10 ) Suggested solutions corresponding data are stored and these data can be addressed by error data. Device for monitoring the printing parameters of a printing machine, comprising - a printing machine ( 1 ), - a control station connected to the printing machine ( 2 ), - one to scan a first test chart ( 4 ) spectrophotometer ( 6 ), the spectrophotometer providing at its output spectral values associated with the first test chart, and - an evaluation unit for evaluating spectral values, characterized in that it comprises - a database ( 10 ) for non-volatile storage of the spectrophotometer ( 6 ) has provided spectral values and - the evaluation unit a with the database ( 10 ) connected computer unit ( 11 ) which accesses spectral values stored in the database and processes them to obtain result data. Apparatus according to claim 15, characterized in that the computer unit ( 11 ) is connected to a printer by means of which the result data is output. Apparatus according to claim 15, characterized in that the computer unit ( 11 ) with a display unit ( 12 ), on the display of which the result data are displayed. Device according to one of claims 15-17, characterized in that the spectrophotometer ( 6 ) continue to scan a proof chart ( 3 ), the database ( 10 ) is provided for the non-volatile storage of the spectrofile values belonging to the proof chart, the computer unit ( 11 ) performs a comparison of spectral values associated with the first test chart with spectrophotal values associated with the proof chart and outputs result signals which are dependent on the degree of coincidence of the spectral values compared with one another. Device according to one of claims 15-17, characterized in that the spectrophotometer ( 6 ) is further provided for scanning a second test chart, the database ( 10 ) for the non-volatile storage of the spectral values associated with the second test chart, the computer unit ( 11 ) performs a comparison of spectral values associated with the first test chart with spectral values associated with the second test chart and outputs result signals that depend on the degree of coincidence of the spectral values compared with one another. Device according to one of claims 15-19, characterized in that the result data are control signals, the computer unit ( 11 ) with the control desk ( 2 ) of the printing machine ( 1 ) via a control line ( 15 ) and the control signals provided by the computer unit are supplied via the control line to the control station. Apparatus according to claim 15, characterized in that the result data correspond to a modified ICC profile, the computer unit ( 11 ) with the raster pulse processor of the printing press ( 1 ) and that of the computer unit ( 11 ) are supplied to the raster pulse processor. Device according to one of claims 15-21, characterized in that the database ( 10 ) is provided for the non-volatile storage of production data associated with a set of stored spectral values. Device according to claim 22, characterized in that that the production data contains information about an order number, a paper type, a measuring method, a measuring geometry, a measuring device and / or Machine data included. Apparatus according to claim 22 or 23, characterized in that it has an order processing computer ( 14 ), the order processing computer with the database ( 10 ) and the order processing computer transfers the production data to the database. Device according to one of Claims 15-24, characterized in that the database ( 10 ) is provided for the non-volatile storage of virtual reference data. Device according to claim 25, characterized in that it comprises an input unit ( 13 ) having, by means of which the virtual reference data can be entered. Device according to one of Claims 15-26, characterized in that the database ( 10 ) is provided for the non-volatile storage of error data. Device according to claim 27, characterized in that the database ( 10 ) is provided for the non-volatile storage of proposed solutions corresponding data which are addressable by the error data.