The most common method used to check the print quality during printing operations. Whether it is monochrome printing or color printing, Offset Printing the operator must often use their own eyes will be printed and proofs repeated comparison to find out the difference between printed and proofs, timely correction to ensure the quality of printed products.
The strength of light not only affects the color of light, but also change the color of the appearance. Offset Printing Printing workshop to see the table must meet the requirements, Offset Printing the general requirements of the illumination to 100LX or so, in order to correctly identify the color.
In production practice, most of the work in the power of the irradiation, Offset Printing and each light source with a certain color. This is to correctly determine the original or product color to bring some difficulties, color under the color, color change is generally the same color lighter, Offset Printing complementary color darker. In the printing workshop, generally choose a higher color temperature (3500 ~ 4100K), better color coefficient of fluorescent light as a sample of light, Offset Printing but pay attention to the fluorescent slightly blue and purple.
Why is there a color contrast reaction? This is because the first look at the color of the color of the color nerve fibers excited, immediately look at other colors, Offset Printing other color nerve quickly excited caused by color, and look at the color of the color of the nerve in the excitement after the excitement, and then excited Slow, Offset Printing causing a negative hue reaction. This reaction coupled with the new color of the hue, the formation of a new color, so after changing the color. And change the hue or regular, is to look at the color of the complementary color changes.
Monochrome offset press is a wet stack overprint, Offset Printing printing color order is generally: green, magenta, yellow, black. In order to minimize the overprinting color, better to bring out the important color of the graphic, should be a reasonable printing order. In addition, Offset Printing in the printing process of monochrome offset printing machine, you can first print on the accuracy of the overlay is not particularly high yellow and black, and other paper gradually stabilized and then printed on the need for high precision printing precision printing, Offset Printing which can effectively avoid After the printing of the overlay on the high precision and overprint is not allowed to produce the phenomenon.
In the process of printing two-color offset printing machine generally use the following printing order: 1-2 color for the magenta - green or green - magenta, 3-4 color is black - yellow or yellow - black, but also according to specific requirements to flexible Adjustment. If you want to highlight an important color (such as green), it should be in accordance with the magenta - yellow, green - black sets of printing order to print, Offset Printing in order to obtain the ideal printing effect.
Four-color offset printing machine printing color order is generally black, blue, Offset Printing magenta, yellow, which cyan and magenta order visual picture of the situation flexible exchange. Multicolor printing (more than four colors) when the color arrangement is more complex, in general, Offset Printing large area spot color should be arranged in the back of the group, Offset Printing but need to put in front of the yellow. Gold, silver ink generally on the later color groups, outlets and the field of overprint, the network must be placed in front of the field on the back.
In the process of color arrangement also consider the color transparency. Offset Printing Wet wet printing, white ink, gold ink, silver ink and other ink can not be printed at the same time, must be printed twice or hollow printing.
In addition, Offset Printing the color arrangement should also consider the ink viscosity. Offset Printing Under normal circumstances, should be used to reduce the viscosity of the ink printing order to ensure the quality of printed materials.