Graphic technology--Application of reflection densitometry and colorimetry to process control in graphic arts
Some standard content:
GB/T18722-20C2
This standard adopts the international standard (9013655, 2000 Printing Technology Reflectivity Measurement and Colorimetry Measurement Basic Points in Printing Process Control and Printing Product and Sample Evaluation) and is formulated to ensure the basic protection of the original international standard structure and content, and has made modifications to suit the writing rules of our standard in production and editing. This standard's annex A, appendix B, and appendix C are provided. This standard is proposed by the General Administration of Press and Publication of the People's Republic of China. This standard is under the jurisdiction of the National Printing Standardization Technical Committee. The originating units of this standard are: Beijing Printing Academy, China Institute of Printing Science and Technology. The main drafters of this international standard are: Hui Lin, He Laozheng, Qi Xiaodian, Yao Dongxin 175
GB/I18722-2002
ISO Foreword
TS (International Organization for Standardization) It is the world federation of national standards bodies (ISOC member bodies). The work of formulating international standards is usually done through ISO Technical Committees. A corresponding technical committee is established for each topic. Each member body interested in its topic has the right to become a representative of the technical committee. All parties or non-official international organizations cooperating with ISO may also participate in this cooperation. In the standardization of electrotechnical technology, ISUO works closely with the International Electrotechnical Commission (IEC). The drafting of international standards is based on the criteria given in Part 1 of the Introduction to ISO/TC:130. The draft international standards prepared by the technical committees are subject to voting by the member states. The formal publication of an international standard requires the approval of at least 5% of the member states: International Standard 1S01365 was drafted by TS)/TC:130 Pre-press Technical Committee. The name of the International Standard 15) 13656 is Patented Technology for Printing - Application of Curve Width Measurement in Printing Control and Product and Sample Strength Evaluation.
Note: Some of the contents in this international standard have patent issues: IS) does not claim legal patent rights. Appendix A, Appendix and Appendix C of this standard are not included in the B/T18722-2007 ISO standard. Reflectance density meter and colorimeter (micrometer or photometric type) are both application type measuring instruments for measuring the reflectance coefficient of reflective materials. Although these instruments have similarities, there are still essential differences between them. First of all, the colorimeter used in the printing is not just as its name indicates, it does not display the world density value (the logarithm of the weighted average reciprocal of the luminous flux!), and other parameters can be deduced from these and displayed in quantity. The colorimeter displays different weighted averages of the reflectance of the Nixie light, and can often show different conversion values of these values. Therefore, it is necessary to define a more uniform one like CIELAB. Color space. Reflection densitometers (as defined in 15 () [-3) require that the incident light flux has the light energy distribution of the standard illuminant A. In the color flux, IS13655 stipulates that the light energy distribution should meet the lighting requirements of CIFT2F0, but such a light source is not easy to achieve. It requires that whether using natural color filters or calculating spectral light measurement data, 1D50 is used together with a certain weighting function to calculate the three material differential values, thereby effectively defining the light response. In practice, most people who use spectral photometry to measure color in printing use a light source with a distribution similar to that of the standard illuminant A, and use the measured spectral reflectance data to calculate density and color values. For color measurement, when the object being measured is a fluorescent object, an erroneous result will be obtained, and the color accuracy measurement will be inaccurate. In order to provide the fastest possible response to the viewer's needs, in printing, color matching and the establishment of color standards, portable colorimeters with low prices and small sampling apertures are used as a supplement to colorimeters in the printing process control.
Densitivity measurement in printing is the amount of colorant per unit area on the uncontrolled printed product. 1O5·3 defines a number of situations, each corresponding to a specific laboratory condition. For ten-tone printing, the density variation is a function of film thickness and tone value. Density measurement is also used in other aspects of quality control.
For a long time, reflective type meters were used first when preparing color separations, while broadband color films were used to measure the density of continuous-tone color copies. With the improvement of printing quality, the density of the printed product has gradually increased. Reflection densitometers are also used in printing process control. The measurement area is mainly for measuring single package defects (yellow, magenta, etc.). It has been found that the use of color filters has advantages over the printing process control. These include: reducing the effect of small hue shifts in density. A pair of yellow and magenta are very sensitive to color and color adjustment. Improve the consistency between the instruments: the linear relationship between width and thickness is extended to high density ranges to reduce the amplitude of density additive failure. It is also found that the deflection filter can reduce the effect of the first surface reflected light. The densitometer with deflection coating has almost no effect on the oil dryness. Deflection filters will also have an impact on the above two properties. The instrument designer needs to improve the optical harmonic calculation described in 15-3 and the accompanying document of this standard. Standard requirements for the minimum effect of optical filters are listed in IS14. The widespread use of colorimetric measurements has led to the widespread use of wideband and narrowband instruments and polarized mirrors in printing, and colorimetric measurements have also been widely used. There are many different colorimetric measurement methods in industry, so relevant international standards have been created: due to the continuous exchange of process control information between manufacturers, it is important to clearly define this content. By defining terms, specifying measurement methods and requirements for measurement and control conditions, and standardizing the review process, uncertainties will be minimized. Many of the parameters that are tested or calculated in the printing process, including some parameters later defined in this standard, do not require special optical filters. They are all comparative formulas, and in many cases are calculated directly from reflectance data. Density and chromaticity parameters are derived from the common concave groove: in each independent production environment, different most can be derived from the appropriate spectral product, which can have the same effect on process control. Excluding these products and is not accurate, however: in some cases: using specific light products or special parameters for communication in the production link: and unifying the printing quality method is also very important. This international standard specifies the method of reporting test results based on the color and density based methods commonly used in most printing processes. In color printing, some variables must be controlled in order to achieve the expected results. For a given substrate, the most important process variables are the total printed solid color quality (CMYK solid color ratio) and the color of the overprinted color blocks, dot deformation/reflection and tone value. For printing conditions where there is no defined convex control, this standard will define the pre-printing control block, the allowable minimum size of a color block and the tone value deviation range. This standard also defines the requirements for measurement and control films, the method of sub-cutting and the reporting method of measurement results, and the measurement method for the measurement speed used in film, direct platemaking and direct printing methods. The standard will describe the parameters obtained by the reflective device and are useful for the whole process. First, the method used is specified to facilitate communication between users. Parameters usually defined in the industry (such as density measurement, color cabinet error and grayscale print contrast and dot setting) are not recommended for general use. They are not suitable for screening in this standard. Color density (generally defined as 1og (X/) 1g (0/Y and 1.0g (/) where X:Y:2 is defined as the three-dimensional micro-head or reflective character of the substrate) is excluded because their spectral product does not meet the requirements of this standard. Many parameters specified in this standard, especially those of basic window measurement technology, are very important for printing process control. The technology can accurately describe the appearance of the printed product. Some parameters are suitable for production overlay control, while others are suitable for determining the difference between samples and printed products and the changes on the same printed product. In addition, it also contains data for evaluating the characteristics of the media, such as shadow, etc. Some of these parameters are measured by color width, but density is still the dominant measurement method. When color reproduction and color matching are to be performed, colorimetry is generally preferred to chromaticity measurement, unless the subject matter is very close to this industry.It is recommended to use the C-LAB color space specified in ISO 13655 for colorimetric measurement. Therefore, it is more useful to use parameters such as chroma, chroma and chroma angle in analyzing the appearance of samples than to use them alone. When color matching is performed, the sample with the smallest color difference from the object being photographed is selected, although this will have some restrictions on chroma, hue and chroma - for example, for a neutral secondary color, it is important to determine that it has only a low luminance value and a certain brightness value. National Standard of the People's Republic of China, Reflection Density Measurement and Color Measurement, Printing Technology, and Application of Reflection Density and Color Inspection in Printing Process Control. 1 Scope
GB/T18722-2D2
eq1so13656.2000
This standard specifies the application of density measurement and colorimetric design in the printing process, including: minimum requirements for control; reading method; and reporting method of results.
This standard is applicable to the evaluation of density measurement and colorimetric design through the production of individual sheets and the evaluation of total color and multi-color proofing sheets.
2 Referenced standards
The following standards contain the following documents, which are referenced in this standard or are related documents of this standard. When this standard is issued, the documents shown are valid. All standards are subject to revision. To ensure the accuracy of this standard, the latest version of the following standards shall be used. GB/T11501939 Light falling conditions (m:S) 513:19H4) G174.19 Bureau of Technology Adjustable color separation films, samples and printed products Process control Part 1: Parameters and test methods (egv1512647-1:1$96) GH 17954.2-1%34H Quality technology network Adjustable color separation films, samples and printed products Process control Part 2: 49
1505-3:1995-
Long degree measurement of the most common part, Pei Ce
JS54:1UU5 plate shadow "-suite shop measurement - Part 1: War radiation conditions 90737:1
Optical measurement of standard printing and preparation | |tt||TS12G53:1996 Standard measurement and colorimetric calculation of printed images 1S014S81 Printing technology - Specification, method and measurement conditions of reflectometers for printing IS)/IS57) Printing technology and photography - Reflectometers - Recognized standard materials for use in the determination of radiation resistance and colorimetric analysis
3 Definitions
3.1 Aperture
An optical device for determining the internal area of a test sample. 3.2 Colorimeter
An instrument for measuring colorimetric values
Approved by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China on 2002-05-21 2093-01-01 Quantity
GB/T18/22·2002
Task: The three-stimulus detection is to check the material by measuring the high rate or induction of emission, the stable production and the standard brand color film, and obtain the chromaticity value according to the method of multiplication and integration. The total colorimeter shall obtain the corresponding value through the head mirror light reflection fast or trace emission effect data. 3.3 Control block cntrolpateh
Out of ten test or control blocks (out of network points, Line system changes to the actual geometric figure composition 》34 measurement and control strip untrullrip
one-dimensional broadcast array control block set,
35 center density orednslls
single non-complaint that is, the national pixel continues (draw two points minus line kill) center front suitable shooting density seat 3.6 old library denslly
see 3.2.2 reverse time general degree,
standard: in this standard, a beautiful exchange live Sichuan Shi support shooting super product, no special say. Then Sichuan density river, 3.7 Daubling
Sluratrh
Control block for evaluating the actual pressing state.
3.8 Film
Contains a good or bad image in a long simulated form. Note: This control block must include a color correction film and refers to a single color separation film. 3.9 Film positive and negative
lmpolarinyFpolardtyofaFilmn) positive and negative images|| tt||The film in which the blank part and the solid part correspond to the non-printing part and the intermediate part of the printed product respectively is called positive film (positive film): the film in which the blank part and the solid part correspond to the printing part and the non-printing part respectively is called graphic film (positive film).
3.10 Edge width (refers to the width of an opaque image element) The frinewidth corresponds to the half-height of the center concentration of the small dots required by the front printing method. Unit
: This item is only for film.
3.11 Halftone adjustment
The white screen line is a variable-shaped image composed of two dots. 3.12
The unit of the image obtained by the recovery element inugeelemeat
, see 3, 3.13 Incident light flux ncldentflux
The light flux irradiated to the sample under test, 3.14 Ink overprint rate iak Irup
The level and volume of the first layer of color on the first color continent. This is a low measurement. Notes
1 Printing rate percentage
2 This is not a clear indication of the external cabinet, 3 The optical quality can be verified by the optical method,
375 Midtone balance control block midtnnehalanrecautrolpatrh A control block on the control strip composed of cyan, magenta and iris points in a natural balance state on the film: Also learn the color level adjustment constant at %~·6U5, the residual color and magenta corresponding level values can be used to produce a neutral point color: 3.16 Non-periodic halftone adjustment noa-periudiehalr-tune has the same teaching element (such as point), G
3.17 Print sample (Kprint: OKsheet
CB/T18722-2002
The printed product selected in the printing production process as a reference for the subsequent printing operation. 2.1B Overprint
In the case of two or more layers, the latter layer is on the former layer, generally refers to a layer of printed material on the former layer.
3.19 Print substrate
The carrier (material) that carries the printed surface
3.20 Basic printing colors (for four-color printing) proeesscolours (farfomr-rolor printing): yellow, magenta, red and black.
3.21 Reflection coefficient
renectmmee fuclor
Emissivity
The ratio of the light emitted from the sample to the light emitted by the diffuse reflector at an intermediate position. Total position: 1.
3.22Reflection density rerlecilondensilyirefleelunccFaetor (optlcal)denglly 10The logarithm of the reciprocal of the effective range coefficient: F--g(I/R) single.1.
3.23Reflectometer refetumeler
optical instrument for measuring physical quantities related to surface reflection under specified geometry and light potential conditions, 3-24
relative density
minus the density of the color separation film or unprinted substrate 3.25the area of the sample perforation detector for testing.
3.26screen sequence rate screenrling number of dots in the line graph in the direction of light generation, unit length, unit; rm
3.27screen width
screen practice reverse
single tca
3.28solid 90ld
the image without dot structure with uniform color density and 10% rendering ratio. 3.29 Spectral prnd1t
The product of the spectral output of the incident light at the desired wavelength and the spectral response of the receiver 3.3 (receiver) The product of the spectral response of the photodetector and the spectral response of the optical components associated with it. 33) Tone value (dot area coverage percentage) Tone color (anaprint) The color effect in percent on the dot panel of a toned print (if other optical phenomena on the substrate are ignored). The calculation formula is:
Rongzhong: Wei:
18722·-2002
rl,?* - 100 X [1 - 1u--n,-n, :1[ - 1-r* a is the wind radiation density of the non-printing position of the printing substrate; the solid reflection density
is the reflection variation of the dot part.
The formula for the relative reflectivity is
A./% = 100 (K
Formula:
Reflectivity of non-printed material, K.
Reflectivity of actual reflectivity:
Reflectivity of dot area
Printed product price adjustment is called "equivalent dot area" or "same dot density", and the "dot volume" is only used to adjust the image of the dot group under the river, which is an approximation of this value that can be used for printing.
R3/:R, - R.)
Generally speaking, in the most electronic text, the tone value of the standard is considered to be non-mechanical. The formula is Murray-Dair formula
3.32 positive color separation film tone value (two-point area coverage percentage) tone value idnlarca (onahalf-tone film of positive polarity)
calculation formula is:
where:.
A = 100 × [1
:0 : +:J/_1
network day home film above the ground fullness: P.
solid part of the time density:
dot Lige of the selected element,
3.33 Langguo color separation Ma level value (same point area coverage percentage) lunewahuedntarea (aniahalf-tone film of positive polarity) pnlarity?
The formula is:
A-/% = 16: - 100 × [1 - 13-0%,-7/+ - 10: *-(4
The selected transmittance of the airborne position above the network glue meter: the vertical control density of the ground part;
The transmittance of the dot part
3.34The tone value increase
tone value increase
The dot increase
The difference between the tone value of the printed product and the tone value of the film or the tone value of the stimulus output message, unit: Xing,
Synonym\dot book\Only used for the dangerous river composed of two points, 4 Technical requirements
4.1 Measurement and control clause
4. 1. 1 The glue ratio is measured according to the relevant parameters of the test parameters in GB/T1791.21999. 4.1.2 The measurement and control system is the lowest requirement. For example, the center density width, the edge width of the dot and the base density. The measurement and control strip should include the change of the base color monochrome solid color block to its overprint color, that is, KL.M, Y, (C+142
GB/T187222002
M). (center Y. (M+Y) and C-MY) this color fast. In addition, the measurement strip should include at least 3 defined screen color blocks, and indicate each printed drama. .CM, Y standard gradation, in the defined screen tone control color style, a color block gradation value should be 21% ~ 30, another color block gradation value should be 40% -50, the first block should be 1% -80%; there should also be a measurement of the middle leveling screen control gap and the following blocks, in the entire printed sheet as much as possible with the complete format:
the dot shape of the image used in the process control should be circular dots, the difference between the number of screen lines and the screen level of the image should not be greater than: 1-, all the gradation values (including the post-calculation) are completely controlled within the standard value of 1. In summary
1 for negative image pressure combing, to add the following and The above control block 2 should be explained that the points in the control block are two points in the wind system, and in actual production, the network can be built later, square, depicted, etc., but the same point in the shape can be set to check the sound format, print, and check the display of the industry. 4.2 Preparation for measurement
Make sure the measuring head is clean. Preheat it according to the preheating time recommended by the resistor manufacturer, and then calibrate the instrument according to the manufacturer's instructions. Set the instrument to the required mode. Make sure the sample is flat and there is no damage. Place the sample on a flat black surface and center the sample light hole. The light hole should be within the lighting area (specific S) 5-1. The sampling hole is placed between the control block to be measured: Section 10: The bottom of the instrument Rub the samples so that they are in the same plane. During the day, the diameter of the sample aperture should be [5 times smaller than the line width of the sample aperture: For non-periodic sampling light, the aperture should be smaller than 4m. If the pixel is smaller than the recommended aperture, one more number should be added: 4.3 Calculation of the density of the sample
4.3.1 The measurement method specified in S14981
4.3.2 Measurement report
Any measurement result report should clearly state the measurement conditions. The measurement station report should show that it meets the requirements of the standard. The report should include the following:
Model, name, and frequency! The color channel (cyan, yellow or yellow) is represented by the wavelength of Im. The light is transmitted along the wavelength into one of the IO standard states I, E defined in ISO53; a polarizer (with/without)!
Try to select the backing (if not black)
deep sample light hole (ma);
a corresponding band (to print the material, the strength or absolute value of the material should not be required for the value of the material and the market). The uncertainty of the filter standard (ISO157) is not required. 4.4 Chromaticity value
4.4.1 Report the density
colorimeter, German certification conditions and calculation should be 1$): 3655 provisions, such as the use of a case value colorimeter, the measurement conditions (add backing material, what conditions are required] should meet 131 3655 provisions: some color problems can be calculated from the data, this receiver can be equipped with a health light sheet, in this receiver package model self-deduction sea
442 test product installation safety report
the proposed report should be in accordance with S0136 on the requirements of the colorimeter data, and indicate the exact conditions of use: the report should include the following parameters:
GE/T18722-2002
the type, name and manufacturer of the colorimeter (if it is a stimulus value photometric disk type, it should be noted); the back of the sample is black: ||tt| |- Sampling hole (mm)
- Uncertainty of the filter standard (ISO 05790). 5 Measurement method
5.1 Deviation of solid color samples on the printed sample and the proofing sample The color difference CIFI.ARF of the corresponding points on the printed sample and the proofing sample is calculated, and the result is compared with the deviation specified in the relevant part of GB/T17931: 5.2 The solid density or the density of the printed color is measured by the highest gradient reading of the printed basic color. Color channel measurement of actual density and blank density: In the density test result report, the actual density value should be recorded directly. Relative density calculation formula: DD-D
Formula: Relative density:
——real density!
: \-blank density.
5.3 The step value of the printed product
is selected to obtain the color channel when the maximum value of the printed product is measured. The blank density, actual density and the fastness of the specified basic color block of the printed product are measured. The results cannot be directly displayed by this meter, so it can be used.The formula is used to calculate the tone value from the density. The 1-level adjustment (three-dimensional area gain percentage) is somewhat related to the instrument, especially the two-color, with a guaranteed film width measurement of the width of the film or digital file. The 2-level measurement (dot gain) is obtained by measuring the difference between the adjusted value on the printed product and the film or digital file. The value of the increase in the control line must be determined by at least 3 levels of adjustment, and the control head on the film must be changed by 1% with an increment of 10 to estimate the difference between the adjusted value on the embedded film or double-word material. The curve is reduced by dividing the function (dot gain function) to estimate the increase in the training function. 5.4 The apparent printing rate
Use the color channel with the highest color sensitivity to obtain the third color channel to obtain the gradient of the first solid color, the second solid color and the overprint solid color, and use the Preil formula to provide the apparent printing rate
f=<..... D,/
Where:
D,: ... From this we can see that different positive and negative channel samples produce different results, 2 security (weight percent oil overprint rate, can be more use the weight method described in the appendix of this test, the printing quality measurement and image analysis technology, can provide relevant information about the oil and its fast circulation of the oil, the apparent overprint rate is not selected to provide this information to the user, 3 grid collection overprint rate can be controlled or monitored by the cow production changes, the hospital Guang P: formula area There are many other formulas available, the final number is public or derived from the formula, but these formulas are abandoned! Color sequence agent sugar color channel in the relevant, 5 with bias rejection film and other wind band is more scientific than those without full film density meter dragon I, 281
5.5 again color/enterprise shape
GB/T18722-2C0?
Select the appropriate amount of color channel, measure and record The difference in reflection density between lines in different directions on the same sheet is the relative value of ghosting/deformation.
5.6 Density measurement on the same sheet
To measure the uniformity of a particular print, it is usually necessary to eliminate the change in the direction or width of the ink, for example, to eliminate mechanical distortion and other printing faults in printing. Density measurement is usually carried out on a single solid sheet to accurately determine the cause of the fault.
Because color measurement can more accurately show color difference, when it is necessary to determine the printing effect by the change of solid block or screen color, it is necessary to use emergency measurement.
5.6.1 Density measurement
Use the instrument to read the maximum density, measure the density change of the single solid sheet, and express it as white percentage. The calculation method is: [(Dn/Du.)—] x 10%
Where: ..., the maximum span value of the solid color on the print: D...——the minimum density value of the solid color on the print. 5-6-2 Color inversion measurement
The color difference A of the CIEI.A of the splash print with opposite structural colors (such as "K12C62M45Y100*\K100%\\balanced color C75M70Y70\) is a ratio, and the color difference value of the corresponding measurement position is recorded. 5.7 Print solid color change
Select at least 15 representative sheets from the batch of products. If the number of prints exceeds 1G00 sheets, increase the test sample according to the ratio. The solid color on the test strip is in urgent need of measurement, and the measurement result is consistent with GB/ 17934 (15U12647) and the corresponding sections. 5.7.1 Chromaticity Measure the relative "difference" of the LAB number of each tested print and calculate the value and standard deviation. Then multiply the standard deviation by 1. Determine the confidence range (the range of the single product) and then calculate the CIELAB color value (of each average value) required. The color difference obtained by multiplying the half mean represents the color difference between the printed product and the sample, and the color difference obtained by multiplying the half mean represents the color variation between the batch and the printed product. 5.7.2 Density The instrument is connected to the color channel with the highest reading of the tested print. Determine the difference between the average density of the sample and the batch of printed sheets at the corresponding position, and calculate the statistical values of each position, "mean value" and "standard value". These two values represent the direction and change of the actual color deviation at the test position. Appendix A (indicated by the manufacturer) of GB/T18722: Test method for the apparent trapping of oils The following is a test of the amount of oil printed on the substrate before printing and the amount of oil printed on the substrate before printing. This method is not intended to be used as a whole step in the preparation of samples) 77 Preparation of standard prints for optical testing Print the first color sample on a printing instrument with a solid disc to achieve the desired colorimetric or density detection: Print a second solid wet sample on the substrate printed with the same solid disc to achieve the specified colorimetric or density value. The required thickness of the ink transferred to the printed substrate is determined by obtaining the amount of ink reduced on the substrate or the amount of ink added on the substrate (if an accurate analytical balance is used, the increase in the printed substrate will be more accurate. This is not affected by environmental conditions. The value of the substrate weight test is a separate print of the first color. Use the same printing plate to print the second color on the first color layer and determine the thickness of the second color layer. The thickness of the second color layer is 5%. The formula for calculating the ink overprint rate is as follows:
Ja-locis/s .
In the formula, the density of the mother method is:
5. The second color is overprinted. The second color is printed separately. The density of the second color should be reported in the order of the month.
Note: The absorption of the first color is higher than the absorption of the printed material. The absorption of the printed material is usually close to %, and it will be higher if it is printed properly. Appendix B
Complete sensitivity!
Density measurement bias phenomenon
From the last table, the reflected light is composed of two parts: the first part of the reflected light is the "light of the sample" and the second part of the reflected light is the "light of the sample". \ is relevant, only the second part of the incident light depends on the color. In the printing process control, the basic method of measuring the unit area rent and the force of the quantity is provided: some space meter manufacturers actually measure the first part of the incident light for the specific test machine. The standard 0°/45\ or 4\/C can eliminate the influence of the spectrum reflection. However, for low-light surfaces, these conditions are not suitable for witness detection: some manufacturers use a vibration device to eliminate the light reflected from the surface:
Obviously, although the polarization device will feel the difference between density and the design. The system has the following advantages for process control:
helps the approximation between the amount of color per unit area to a wider range and reduces the relative failure rate of density.
- reduces the dependence of the reflectivity on the ink level. It is important to consider the spectral characteristics of the polarized film when making instrument modifications. The optical characteristics of the machine are very important. The spectral characteristics of the polarized film that meet the 1S·3 and [SO--- specifications will not meet the 1S·3 and 1S)5-4 specifications when the polarized film is installed. The density of the film that meets the 1S)5- and S5-4 specifications may not meet the 1S)5- and S5-4 specifications after the relevant film is removed! SU5-4 stipulates that the density of the machine with polarized film should be changed. The sample is required to be commercially available. The optical characteristics can be evaluated by measuring the wide calibration band of the non-polarized film.)——density of the second color of a single color.
c The first color obtained by running on the same line, the proposed 1
color sequence, the amount is the same, the printing machine can not move, this is because of the unclear nature of the scene, more importantly, the choice of the road is different. From this we can see that different positive and negative channels produce different results, 2 (weight) oil overprint rate, you can use the weight method described in the appendix of this test, the quality of the print and image analysis technology, can provide information about the addition of oil to the printing material and about the oil cycle, the apparent overprint rate is not selected to provide this information to the user, 3 grid overprint rate can be controlled or visually produced changes, the hospital Guang P: formula area There are many other formulas available, the final number is public or derived from the formula, but these formulas are abandoned! Color sequence agent sugar color channel in the relevant, 5 with bias rejection film and other wind band is more scientific than those without full film density meter dragon I, 281
5.5 again color/enterprise shape
GB/T18722-2C0?
Select the appropriate amount of color channel, measure and record The difference in reflection density between lines in different directions on the same sheet is the relative value of ghosting/deformation.
5.6 Density measurement on the same sheet
To measure the uniformity of a particular print, it is usually necessary to eliminate the change in the direction or width of the ink, for example, to eliminate mechanical distortion and other printing faults in printing. Density measurement is usually carried out on a single solid sheet to accurately determine the cause of the fault.
Because color measurement can more accurately show color difference, when it is necessary to determine the printing effect by the change of solid block or screen color, it is necessary to use emergency measurement.
5.6.1 Density measurement
Use the instrument to read the maximum density, measure the density change of the single solid sheet, and express it as white percentage. The calculation method is: [(Dn/Du.)—] x 10%
Where: ..., the maximum span value of the solid color on the print: D...——the minimum density value of the solid color on the print. 5-6-2 Color inversion measurement
The color difference A of the CIEI.A of the splash print with opposite structural colors (such as "K12C62M45Y100*\K100%\\balanced color C75M70Y70\) is a ratio, and the color difference value of the corresponding measurement position is recorded. 5.7 Print solid color change
Select at least 15 representative sheets from the batch of products. If the number of prints exceeds 1G00 sheets, increase the test sample according to the ratio. The solid color on the test strip is in urgent need of measurement, and the measurement result is consistent with GB/ 17934 (15U12647) and the corresponding sections. 5.7.1 Chromaticity Measure the relative "difference" of the LAB number of each tested print and calculate the value and standard deviation. Then multiply the standard deviation by 1. Determine the confidence range (the range of the single product) and then calculate the CIELAB color value (of each average value) required. The color difference obtained by multiplying the half mean represents the color difference between the printed product and the sample, and the color difference obtained by multiplying the half mean represents the color variation between the batch and the printed product. 5.7.2 Density The instrument is connected to the color channel with the highest reading of the tested print. Determine the difference between the average density of the sample and the batch of printed sheets at the corresponding position, and calculate the statistical values of each position, "mean value" and "standard value". These two values represent the direction and change of the actual color deviation at the test position. Appendix A (indicated by the manufacturer) of GB/T18722: Test method for the apparent trapping of oils The following is a test of the amount of oil printed on the substrate before printing and the amount of oil printed on the substrate before printing. This method is not intended to be used as a whole step in the preparation of samples) 77 Preparation of standard prints for optical testing Print the first color sample on a printing instrument with a solid disc to achieve the desired colorimetric or density detection: Print a second solid wet sample on the substrate printed with the same solid disc to achieve the specified colorimetric or density value. The required thickness of the ink transferred to the printed substrate is determined by obtaining the amount of ink reduced on the substrate or the amount of ink added on the substrate (if an accurate analytical balance is used, the increase in the printed substrate will be more accurate. This is not affected by environmental conditions. The value of the substrate weight test is a separate print of the first color. Use the same printing plate to print the second color on the first color layer and determine the thickness of the second color layer. The thickness of the second color layer is 5%. The formula for calculating the ink overprint rate is as follows:
Ja-locis/s .
In the formula, the density of the mother method is:
5. The second color is overprinted. The second color is printed separately. The density of the second color should be reported in the order of the month.
Note: The absorption of the first color is higher than the absorption of the printed material. The absorption of the printed material is usually close to %, and it will be higher if it is printed properly. Appendix B
Complete sensitivity!
Density measurement bias phenomenon
From the last table, the reflected light is composed of two parts: the first part of the reflected light is the "light of the sample" and the second part of the reflected light is the "light of the sample". \ is relevant, only the second part of the incident light depends on the color. In the printing process control, the basic method of measuring the unit area rent and the force of the quantity is provided: some space meter manufacturers actually measure the first part of the incident light for the specific test machine. The standard 0°/45\ or 4\/C can eliminate the influence of the spectrum reflection. However, for low-light surfaces, these conditions are not suitable for witness detection: some manufacturers use a vibration device to eliminate the light reflected from the surface:
Obviously, although the polarization device will feel the difference between density and the design. The system has the following advantages for process control:
helps the approximation between the amount of color per unit area to a wider range and reduces the relative failure of density.
- reduces the dependence of the reflectivity on the ink level. It is important to consider the spectral characteristics of the polarized film when making instrument modifications. The optical characteristics of the machine are very important. The spectral characteristics of the polarized film that meet the 1S·3 and [SO--- specifications will not meet the 1S·3 and 1S)5-4 specifications when the polarized film is installed. The density of the film that meets the 1S)5- and S5-4 specifications may not meet the 1S)5- and S5-4 specifications after the relevant film is removed! SU5-4 stipulates that the density of the machine with polarized film should be changed. The sample is required to be commercially available. The optical characteristics can be evaluated by measuring the wide calibration band without polarized film.)——density of the second color of a single color.
c The first color obtained by running on the same line, the proposed 1
color sequence, the amount is the same, the printing machine can not move, this is because of the unclear nature of the scene, more importantly, the choice of the road is different. From this we can see that different positive and negative channels produce different results, 2 (weight) oil overprint rate, you can use the weight method described in the appendix of this test, the quality of the print and image analysis technology, can provide information about the addition of oil to the printing material and about the oil cycle, the apparent overprint rate is not selected to provide this information to the user, 3 grid overprint rate can be controlled or visually produced changes, the hospital Guang P: formula area There are many other formulas available, the final number is public or derived from the formula, but these formulas are abandoned! Color sequence agent sugar color channel in the relevant, 5 with bias rejection film and other wind band is more scientific than those without full film density meter dragon I, 281
5.5 again color/enterprise shape
GB/T18722-2C0?
Select the appropriate amount of color channel, measure and record The difference in reflection density between lines in different directions on the same sheet is the relative value of ghosting/deformation.
5.6 Density measurement on the same sheet
To measure the uniformity of a particular print, it is usually necessary to eliminate the change in the direction or width of the ink, for example, to eliminate mechanical distortion and other printing faults in printing. Density measurement is usually carried out on a single solid sheet to accurately determine the cause of the fault.
Because color measurement can more accurately show color difference, when it is necessary to determine the printing effect by the change of solid block or screen color, it is necessary to use emergency measurement.
5.6.1 Density measurement
Use the instrument to read the maximum density, measure the density change of the single solid sheet, and express it as white percentage. The calculation method is: [(Dn/Du.)—] x 10%
Where: ..., the maximum span value of the solid color on the print: D...——the minimum density value of the solid color on the print. 5-6-2 Color inversion measurement
The color difference A of the CIEI.A of the splash print with opposite structural colors (such as "K12C62M45Y100*\K100%\\balanced color C75M70Y70\) is a ratio, and the color difference value of the corresponding measurement position is recorded. 5.7 Print solid color change
Select at least 15 representative sheets from the batch of products. If the number of prints exceeds 1G00 sheets, increase the test sample according to the ratio. The solid color on the test strip is in urgent need of measurement, and the measurement result is consistent with GB/ 17934 (15U12647) and the corresponding sections. 5.7.1 Chromaticity Measure the relative "difference" of the LAB number of each tested print and calculate the value and standard deviation. Then multiply the standard deviation by 1. Determine the confidence range (the range of the single product) and then calculate the CIELAB color value (of each average value) required. The color difference obtained by multiplying the half mean represents the color difference between the printed product and the sample, and the color difference obtained by multiplying the half mean represents the color variation between the batch and the printed product. 5.7.2 Density The instrument is connected to the color channel with the highest reading of the tested print. Determine the difference between the average density of the sample and the batch of printed sheets at the corresponding position, and calculate the statistical values of each position, "mean value" and "standard value". These two values represent the direction and change of the actual color deviation at the test position. Appendix A (indicated by the manufacturer) of GB/T18722: Test method for the apparent trapping of oils The following is a test of the amount of oil printed on the substrate before printing and the amount of oil printed on the substrate before printing. This method is not intended to be used as a whole step in the preparation of samples) 77 Preparation of standard prints for optical testing Print the first color sample on a printing instrument with a solid disc to achieve the desired colorimetric or density detection: Print a second solid wet sample on the substrate printed with the same solid disc to achieve the specified colorimetric or density value. The required thickness of the ink transferred to the printed substrate is determined by obtaining the amount of ink reduced on the substrate or the amount of ink added on the substrate (if an accurate analytical balance is used, the increase in the printed substrate will be more accurate. This is not affected by environmental conditions. The value of the substrate weight test is a separate print of the first color. Use the same printing plate to print the second color on the first color layer and determine the thickness of the second color layer. The thickness of the second color layer is 5%. The formula for calculating the ink overprint rate is as follows:
Ja-locis/s .
In the formula, the density of the mother method is:
5. The second color is overprinted. The second color is printed separately. The density of the second color should be reported in the order of the month.
Note: The absorption of the first color is higher than the absorption of the printed material. The absorption of the printed material is usually close to %, and it will be higher if it is printed properly. Appendix B
Complete sensitivity!
Density measurement bias phenomenon
From the last table, the reflected light is composed of two parts: the first part of the reflected light is the "light of the sample" and the second part of the reflected light is the "light of the sample". \ is relevant, only the second part of the incident light depends on the color. In the printing process control, the basic method of measuring the unit area rent and the force of the quantity is provided: some space meter manufacturers actually measure the first part of the incident light for the specific test machine. The standard 0°/45\ or 4\/C can eliminate the influence of the spectrum reflection. However, for low-light surfaces, these conditions are not suitable for witness detection: some manufacturers use a vibration device to eliminate the light reflected from the surface:
Obviously, although the polarization device will feel the difference between density and the design. The system has the following advantages for process control:
helps the approximation between the amount of color per unit area to a wider range and reduces the relative failure rate of density.
- reduces the dependence of the reflectivity on the ink level. It is important to consider the spectral characteristics of the polarized film when making instrument modifications. The optical characteristics of the machine are very important. The spectral characteristics of the polarized film that meet the 1S·3 and [SO--- specifications will not meet the 1S·3 and 1S)5-4 specifications when the polarized film is installed. The density of the film that meets the 1S)5- and S5-4 specifications may not meet the 1S)5- and S5-4 specifications after the relevant film is removed! SU5-4 stipulates that the density of the machine with polarized film should be changed. The sample is required to be commercially available. The optical characteristics can be evaluated by measuring the wide calibration band of the non-polarized film.7 Solid color change of printed products
Select at least 15 representative prints from the batch of products for detailed testing. If the number of prints exceeds 100, increase the number of test samples accordingly. The measurement results shall be compared with the error values determined in the corresponding chapters of GB/17934 (15U12647). 5.7.1 Chromaticity Measure the relative value of the LAB number of each tested print and calculate the difference between the average value of the batch product and the standard deviation. Then multiply the standard deviation by 1. Determine the confidence range (the range of the single product) and then calculate the CIELAB colorimetric value (for each average value). The color difference obtained by multiplying the half mean represents the color difference between the printed product and the sample, and the color difference obtained by multiplying the half mean represents the color variation between batches of printed products. 5.7.2 Density The instrument is combined with the color channel with the highest reading of the tested print. Determine the average density difference between the print sample and the batch of printed sheets at the corresponding position. , calculate the statistical values of each position "mean value" and "standard value". These two values represent the direction and change of the solid color deviation at the intercept position. In its own position, the amount of re-condensation 18
GB/T18722
Appendix A
(shown in the table)
Recommendation test of oil overprint rate
The following is an experimental summary of the accurate comparison of the amount of oil printed on the oil layer with the cumulative amount of oil on the substrate before printing. This method is not used as a whole step in the process. Preparation of samples) 77 Preparation of standard prints for optical testing
Print the first color type of sample on the printing instrument with a solid printing disc to achieve the desired single-color detection rate: Use the same solid printing disc to print a second pack of solid wet sample on the substrate printed by the technique. , to achieve the specified chromaticity value or density value. The required thickness of the ink transferred to the printed substrate is determined by obtaining the required amount of ink reduced on the substrate or the required amount of ink added on the substrate (if an accurate analytical balance is used, the increase in the weight of the printed substrate will be more accurate. This is not affected by the environmental conditions of the substrate weight test. The value of the substrate weight is the first color printed separately. The second color is printed on the first color layer with the same printing plate. The amount of ink transferred to the first color layer is determined. The original thickness of the second color layer is: 5% pressure drop of the first color layer onto the first color layer. The formula for calculating the ink overprint rate is as follows:
Ja-locis/s.
Where the weight method is:
5. The second color overprint amount
S, printed separately The color accuracy of the two-color device should be reported in the order of the month.
Note: The absorption of a certain product is higher than that of the printed material. The absorption of the printing is usually close to %, and it will be higher below the surface. Appendix B
Complete sensitivity! bzxZ.net
Density measurement bias phenomenon
The reflected light from the last table: The number includes two parts, the first part of the reflected light and the second part of the reflected light from the surface: The first part of the reflected light is related to the "light of the sample", and only the second part of the reflected light depends on the color. In the printing process control, the basic measurement unit of the color and quantity of the surface is provided: Some spacers are equipped with a mountain map to eliminate the first part of the reflected light in the measurement. For the detailed test machine. The standard 0°/45\ or 4\/C can be used under the condition of the child to eliminate the influence of the spectrum reflection. However, for low light surfaces, these conditions ensure that the quality of the test is appropriate: some manufacturers use a polarization device to eliminate the light reflected from the surface:
Obviously, although the polarization device will have a certain effect on the density, the system has the following advantages for process control:
helps to extend the approximation between the amount of color per unit area to a wider range and reduce the relative failure rate of density,
- reduces the dependence of the reflectivity on the ink level. When modifying the instrument, it is important to consider the spectral characteristics of the polarizing film and its optical characteristics. A non-polarizing film that meets the 1S·3 and [SO-- specifications will not meet the 1S·3 and 1S)5-4 specifications when installed on a polarizing instrument. The density of the film that meets the 1S)5- and S5 specifications may not meet the S5 specifications after the film is removed! SU5-4 stipulates that the density of the instrument with a polarizing film must be changed. The sample must be of commercial optical characteristics. The calibration band can be 15) 14881 without polarizing film.7 Solid color change of printed products
Select at least 15 representative prints from the batch of products for detailed testing. If the number of prints exceeds 100, increase the number of test samples accordingly. The measurement results shall be compared with the error values determined in the corresponding chapters of GB/17934 (15U12647). 5.7.1 Chromaticity Measure the relative value of the LAB number of each tested print and calculate the difference between the average value of the batch product and the standard deviation. Then multiply the standard deviation by 1. Determine the confidence range (the range of the single product) and then calculate the CIELAB colorimetric value (for each average value). The color difference obtained by multiplying the half mean represents the color difference between the printed product and the sample, and the color difference obtained by multiplying the half mean represents the color variation between batches of printed products. 5.7.2 Density The instrument is combined with the color channel with the highest reading of the tested print. Determine the average density difference between the print sample and the batch of printed sheets at the corresponding position. , calculate the statistical values of each position "mean value" and "standard value". These two values represent the direction and change of the solid color deviation at the intercept position. In its own position, the amount of re-condensation 18
GB/T18722
Appendix A
(shown in the table)
Recommendation test of oil overprint rate
The following is an experimental summary of the accurate comparison of the amount of oil printed on the oil layer with the cumulative amount of oil on the substrate before printing. This method is not used as a whole step in the process. Preparation of samples) 77 Preparation of standard prints for optical testing
Print the first color type of sample on the printing instrument with a solid printing disc to achieve the desired single-color detection rate: Use the same solid printing disc to print a second pack of solid wet sample on the substrate printed by the technique. , to achieve the specified chromaticity value or density value. The required thickness of the ink transferred to the printed substrate is determined by obtaining the required amount of ink reduced on the substrate or the required amount of ink added on the substrate (if an accurate analytical balance is used, the increase in the weight of the printed substrate will be more accurate. This is not affected by the environmental conditions of the substrate weight test. The value of the substrate weight is the first color printed separately. The second color is printed on the first color layer with the same printing plate. The amount of ink transferred to the first color layer is determined. The original thickness of the second color layer is: 5% pressure drop of the first color layer onto the first color layer. The formula for calculating the ink overprint rate is as follows:
Ja-locis/s.
Where the weight method is:
5. The second color overprint amount
S, printed separately The color accuracy of the two-color device should be reported in the order of the month.
Note: The absorption of a certain product is higher than that of the printed material. The absorption of the printing is usually close to %, and it will be higher below the surface. Appendix B
Complete sensitivity!
Density measurement bias phenomenon
The reflected light from the last table: The number includes two parts, the first part of the reflected light and the second part of the reflected light from the surface: The first part of the reflected light is related to the "light of the sample", and only the second part of the reflected light depends on the color. In the printing process control, the basic measurement unit of the color and quantity of the surface is provided: Some spacers are equipped with a mountain map to eliminate the first part of the reflected light in the measurement. For the detailed test machine. The standard 0°/45\ or 4\/C can be used under the condition of the child to eliminate the influence of the spectrum reflection. However, for low light surfaces, these conditions ensure that the quality of the test is appropriate: some manufacturers use a polarization device to eliminate the light reflected from the surface:
Obviously, although the polarization device will have a certain effect on the density, the system has the following advantages for process control:
helps to extend the approximation between the amount of color per unit area to a wider range and reduce the relative failure rate of density,
- reduces the dependence of the reflectivity on the ink level. When modifying the instrument, it is important to consider the spectral characteristics of the polarizing film and its optical characteristics. A non-polarizing film that meets the 1S·3 and [SO-- specifications will not meet the 1S·3 and 1S)5-4 specifications when installed on a polarizing instrument. The density of the film that meets the 1S)5- and S5 specifications may not meet the S5 specifications after the film is removed! SU5-4 stipulates that the density of the instrument with a polarizing film must be changed. The sample must be of commercial optical characteristics. The calibration band can be 15) 14881 without polarizing film.
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