Four-color printing, using subtraction three primary colors (yellow, magenta and blue) and black printing. If the primary colors are reproduced with yellow, magenta, cyan and black inks, it should not be called "four-color printing" but "spot color printing" or "spot color printing".
Four-color printing is a printing method that uses three primary colors of red, green and blue and black pigment (ink or dye) to realize full-color reproduction by using the principle of subtractive color mixing.
2. Spot color-Spot color ink refers to a pre-mixed spot color ink (or special pre-mixed ink), which is used to replace or supplement printing color (CMYK) ink, such as bright orange, green, fluorescent color and metallic gold and silver ink, and can also be used as bronzing plate, concave-convex plate, etc. Or as a local light oil pan, etc. It is not a mixture of four colors of CMYK. Every spot color printing needs a special printing plate (it can be simply understood as a pair of spot color films, which are printed separately when printing). Spot color refers to the accurate color.
3. Color pictures are printed in three primary colors (yellow, magenta and cyan) and black. The primary color images used for printing must be separated into separate color plates, and black color plates should be added to correct cyan, magenta and yellow inks and improve the blackness of printed images. These films are used to make four plates for four-color printing.
4. In the printing press, each printing plate must be precisely aligned with other printing plates to obtain high-quality results, which is the industry standard printing method. CMYK printing is a color system widely used in computer printing equipment.
Extended data:
Features of spot color printing:
(1) accuracy
Each color scheme has its own fixed hue, so it can ensure the accuracy of color in printing, thus solving the problem of color transmission accuracy to a great extent.
(2) Opaque
Spot color ink is a kind of masking ink, which is opaque and can be masked on spot color.
(3) Nature of the site
Spot colors generally use solid colors to define colors, no matter how light they are. Of course, you can also color the spot color to present any hue of the spot color.
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