In order to expand the website, controlling the website expansion within the standard range can compensate for the two different forms of website expansion in plate making and printing technology, and Photoshop can expand the website caused by plate making and printing.Methods of improving bar code printing quality.

     The website expansion and compensation measures in printing technology are set by file / CMYK dialog box, and the increase value of standard website and the increase curve of customized website are selected to compensate for the increase of website. Standard dot enlargement value: the standard dot enlargement value designed according to experience according to different paper and ink matching in the software. Methods of improving bar code printing quality.

      Site increase curve: measure the density value of the corresponding color block through the densimeter, calculate the site value and the corresponding expansion value with the MD equation, and select curves from the dotgain drop-down menu to specify the site increase value of 13 percentage points. Of course, the expansion value of the site size at other locations is calculated by the software’s automatic insertion value.

      The transfer function is used to compensate the website. If the image output device used is not calibrated properly, the image will be transferred to the software, and the website may be reduced or expanded. At this time, the transfer function of postscript technology can be used for compensation. The steps are as follows: (1) output an image of C, m, y and K containing 13 gray blocks of dot size designed according to the requirements on the output equipment to be used, and obtain four color separations.Methods of improving bar code printing quality

     The dot area ratio of 13 color blocks was measured by transmission densitometer.Click the transfer button in the file / page setup dialog box to enter the transfer function dialog box.Methods of improving bar code printing quality

    Calculate the required adjustments and enter them in the appropriate boxes. No matter what kind of compensation method, if the pixel value of the adjustment amount is 127, 50% of the stations should be output, but if the 60% stations output by the permutation machine are expanded by 10%, the compensation adjustment amount is 50% – 10% = 40%, and 40% should be input in the box. The permutation machine outputs 50% of the stations desired by the user.Methods of improving bar code printing quality

     Ink overlap and color matching sequence. Because the current color printing adopts wet printing, the color matching sequence is standardized, Generally k-c-my, in order to facilitate ink overlapping, it is beneficial to arrange the ink layer thickness in the order from small to large. We stipulate that black ink thickness = 0.8um, green ink thickness = 0.9um, product ink thickness = 1.0um, yellow ink thickness = 1.1um.Methods of improving bar code printing quality

 The function of printing control rod in offset printing quality process.

       As mentioned earlier, the printing control strip is composed of various sheets for measuring color, printing exposure, color recovery, sample and printing effect. At present, there are many kinds of measuring strips such as Bruner, Fogra, GATF and China Institute of science and technology, but their performance is basically the same, which is generally composed of the following parts.Methods of improving bar code printing quality.

    Local printed matter needs high contrast. K = (dv-dr) / DV is mainly used to detect the change of image contrast station and ink uniformity. DV is the local density and Dr is the printing density of 75% website.Methods of improving bar code printing quality

      The overprint area mainly checks whether the first color accepts the second color and the third color, which affects the overprint rate and thus the ink layer thickness.Methods of improving bar code printing quality.

      The exposure control area of the printing plate checks the tightness between the software and the printing plate to determine the exposure of the resolution of the given printing plate. Generally, it is required to retain 2% of the small websites for the sample plate and 5% of the websites for the printing plate. Exposure control: generally, the exposure is 3 ~ 4 levels higher than the corresponding exposure of the original printing resolution.Methods of improving bar code printing quality.

     The deformation of the shadow and deformation detection station has the identification area of longitudinal, transverse and bidirectional deformation, which indirectly detects the pressure, whether the rubber cloth is loose, and whether the ink volume and water volume are too large.Methods of improving bar code printing quality.

     The halftone area detects the expansion of the intermediate adjustment point, and the gray balance area is used to detect the color recovery. Realizing neutral gray balance is the key to color faithful reproduction. It is worth noting that the measuring rod cannot be copied. The dot edge of the measuring rod provided by the manufacturer is clear.Methods of improving bar code printing quality.

        After copying, it is found that the edge is blurred and the dot is expanded. I am glad to see that China’s printing industry has gradually embarked on the road of data and standardized management. Now there is a gap in the standardization of printing materials, but it will be improved as soon as possible through the efforts of people of insight.Methods of improving bar code printing quality.

      Of course, for the control of printing quality, the experience of technicians is also a very important factor. I believe that with the joint efforts of many people, the control of printing quality, the application of quality management and color management in China will certainly improve the printing quality.Methods of improving bar code printing quality.