We all know the principles and practices of the color sequence arrangement of multi-color machines. In the process of color plate making, the screen angle should be determined according to the primary and secondary color (adjustment) of the original. Because the 45 ° angle has a special sensitivity to human sight, the main color printing plates of the original are made into a 45 ° angle, and the other color angles are 15 °, 75 °, and 90 ° in order. In the process of printing reduction, dots and dots intersect at different angles to form various patterns, of which the cross-shaped pattern is the best coloring effect, and the monk-shaped pattern is second. In the four-color plate-making pattern, only strong colors black, blue, and red can form patterns, and yellow is a weak color, which does not function as a pattern, but only plays a role in color change. Therefore, when determining the angle of the four-color screen in the platemaking, the angle difference between the three strong black, blue and red screens should be made at an interval of 30 °. The result is not only conducive to the color rendering effect, but also prevents the difference between the screen colors 15 °, causing the occurrence of moire faults.
Even if we choose the above-mentioned screen angles of various colors in plate making, when the four-color printing machine arranges the printing, if the color sequence is not arranged properly, the screen angles of the printing plates of the two adjacent color groups may still differ by 15 °. It is possible that color defects, moire, and other ills may occur, and it is impossible to achieve a better effect of printing and restoring the original.
For example: landscape manuscripts tend to be more blue, according to the principle of making the main color plate of the manuscript as 45 °, here we set the blue screen angle to 45 °, the red version is 75 °, and the black version is 15 °, the yellow version is 90 °. In the four-color offset press, the printing color sequence is first black, then blue, red, and yellow. The adjacent red and yellow plates differ by 15 °, especially in the low-key area where the dots are above 75 °. As long as the paper is slightly misaligned during transmission and imprinting, misalignment is likely to occur, causing color casts and mottled spots.
According to the theory of determining the angle of the screen line according to the primary and secondary color (adjustment) of the original, and the problems that often occur in daily production operations, to better solve the problem of color deviation and moire on the multi-color offset press, the solutions are:
First of all, we should check from the source of process design. After accepting the manuscript, the technical personnel of the enterprise and production workshop should first determine the color screen of the 45 ° screen according to the main color of the manuscript; then determine the screen angle of other color plates and the printing of the four-color offset press respectively Color order. For example: For landscape manuscripts with a bluish or greenish main tone, the blue screen is set to 45 °, the black screen is set to 15 °, the red screen is set to 75 °, and the yellow screen is set to 90 °. Set to black first, then red, blue, and yellow in sequence. We believe that during the printing process, the angles of the screen lines of adjacent two colors differ by at least 30 °. According to the sequence of the above-mentioned screens, the black → red phase difference is 60 °, the red → blue phase difference is 30 °, and the blue → yellow phase difference is 45 ° Printing sorting can effectively prevent the occurrence of color shift and moire.
Similarly, for manuscripts with red as the main color, after setting the red version wind to 45 °, the process designer should arrange the red version for printing in the third color group; and stipulate that the black version screen is 15 ° for printing in the first color group; In turn, the blue screen line is 75 °, and it is printed in the second color group; the yellow screen line is 90 °, and it is more appropriate to arrange it for printing in the fourth color group.
It can be seen that the complementary relationship between the above-mentioned network line angles and their color sequence arrangements should attract the attention of the process technicians of the enterprise, and through the organic combination of theory and practice, we can better grasp this law in order to Prevent unnecessary color deviation and tortoises from occurring.
What are the functions of face powder?
1. Make up is lasting. This is its most basic function, and it is also the most recognized and familiar function, because if you do not fix makeup, it is easy to spend makeup, and will also take off makeup. With powder powder, these problems will be solved.
2. Concealer. Loose powder also has a concealer effect, which can block the defects on the face that cannot be covered by liquid foundation or air cushion. It also has the function of hiding large pores. If there are prominent pores or blackheads, it can be solved by powder dispersion.
3. Absorb oil and brighten skin. The powder has a strong adsorption effect on oil. Whether it is applied on the face or hair, it can ensure the dryness of the skin and hair, without worrying about too bright oil. And its brightening effect on skin color is obvious.
Face Powder,Makeup Setting Powder,Loose Setting Powder
Suzhou Yimeijia368 Biological Technology Co.,Ltd. , https://www.yimeijiabeauty.com