Do you want to learn more about spot color printing?

Spot color printing is relative to the four-color printing process. The four-color printing process generally refers to the printing process that uses Y, M, C, and BK four-color inks to copy the color manuscript, while the spot color printing refers to the use of other color inks other than the Y, M, C, and BK four-color inks. The printing process of copying the original. Spot inks can be provided by ink manufacturers, and can also be prepared by Y, M, and C inks. This article will introduce the comparison between the printing effect of spot color and traditional four-color printing, the introduction of spot color printing and the method of spot color ink blending. I hope to discuss it with you to further understand spot color.

1 Spot color and traditional four-color printing effect comparison

From the visual effect of color, the advantage of spot color printing is that the spot color ink is prepared using Y, M, C primary color inks according to the mixing principle of color subtractive color method. Its color brightness is lower and saturation is higher. Spots with uniform ink color are usually printed with spot colors, and the amount of ink is appropriately increased. When the thickness of the ink layer on the layout is large, the sensitivity of the ink layer thickness change to the color change will be reduced, so it is easy to obtain a uniform and thick ink printing effect. The four-color printing is a comprehensive effect of absorption and mixing of the dot additive method and the subtractive color method. The color block has higher brightness and lower saturation. The color blocks printed by the four-color printing process are mostly composed of a certain proportion of dots, and the thickness of the ink layer is strictly controlled when printing the dots. It is easy to change the thickness of the ink layer and the printing process conditions. Changes cause changes in color intensity and dot expansion, resulting in changes in color. Moreover, the change of any one of the colors that make up the color block will cause the color of the color block to change, so that the chance of uneven color of the ink will be multiplied, and the color deviation is prone to occur. If the four-color printing light color block is used, due to the low coverage of the ink on the paper, the ink color is flat and lacks a thick feeling. In addition, the spot color printing has a stable hue, the printed product is clean and uniform, and it can also avoid the moire fault caused by the improper arrangement of the dots.

The usual four-color printing can only reproduce a limited color gamut space, while spot color printing can reproduce more color gamut space, which can reproduce a more ideal and more natural printing effect. Spot color printing can faithfully restore images and improve the vividness and printing quality of copied colors.

2 From the perspective of improving product quality, what kind of products are suitable for spot color printing?

In general packaging printing, spot color printing is often used to print large-area background colors. The cover of packaging products or books and periodicals is often composed of uniform color blocks of different colors or regular gradient color blocks and text. These color blocks and text can be separated and overprinted with four-color inks, and can also be printed with special color inks. In the case of comprehensive consideration of reducing the number of overprints and improving printing quality, spot color printing should be used. For photos taken in the form of color photography that reflect the colorful changes in nature, the painter ’s color artwork or other pictures containing many colors, due to the requirements of craftsmanship, it is necessary to reflect the rich layers and restore the tone of the picture. The four-color printing process should be used to replicate.

When printing large areas of light uniform color patches and large areas of dark color patches, from the perspective of improving product quality, spot color printing is usually used.

When printing a light color block, add a diluent to the primary color ink to prepare the spot color ink, and then perform solid printing, so that the ink layer is thick, and it is easier to obtain a uniform and thick color effect. If printing with four-color printing process, it is necessary to use low-level flat mesh dots, but the low-number dots are easy to make small dots in individual parts due to tiny sand or poor suction during printing, resulting in uneven ink color. Moreover, it is easy to cause poor ink transfer of small dots due to excessive water supply on the plate surface, accumulation of paper powder on the printing plate and blanket, and low paper smoothness, resulting in lighter ink color and uneven ink color.

For dark and large-area color blocks, the four-color printing process may need to be superimposed by several high-color dots of several colors. The ink layer is too thick and the back side is smeared; while the spot color printing process only needs to print one color, It is not easy to get dirty on the back, and it can avoid the possibility of overprinting.

If the picture of a product has both a color gradation picture and a large area background color, the color gradation picture part can be printed in four colors, and a large area background color can be printed in spot colors. The advantage of this is that the four-color printing part can correctly restore the picture by controlling the solid density, and the background color part can obtain a uniform and thick visual effect of the ink color by appropriately increasing the amount of ink. [next]

3 The preparation method of spot color ink

Spot ink generally refers to various color inks other than the series produced by ink manufacturers. If you want to make spot color inks skillfully and accurately, you must master certain basic knowledge of ink color science.

1) Basics of ink toning

Basic color inks include primary color inks, standard inter-color inks and standard multi-color inks.
Primary ink: Refers to three primary inks that cannot be mixed with other colors, namely yellow, magenta, and cyan inks. The standards of four-color inks produced by different countries and manufacturers are not the same. For example, the colors of China's offset printing quick-drying four-color inks are specified as medium yellow, magenta, sky blue and black.
Standard inter-color ink: refers to the color ink formed by equal mixing of any two primary color inks. If the color is red, the mixing ratio is 50% yellow and 50% magenta.
Standard multi-color ink: Refers to the color ink formed by equal mixing of any two intermediate colors or mixing three primary colors in different proportions. Like bronze, the mixing ratio is 50% yellow, 25% magenta, and 25% cyan.

2) Dark spot color ink deployment

Only the primary color ink is used for blending, and the color matching without any diluent is called dark ink blending. According to the principle of subtractive color method, the number of primary color inks should be used as little as possible when mixing dark ink, otherwise the brightness and vividness of the ink will be reduced. However, when blending compound inks of different proportions of the three primary colors, the color shift must be corrected using the complementary color theory. If the green color is too heavy, a small amount of magenta ink can be added to correct it; the red flavor is too heavy, a small amount of cyan ink can be added to correct it; and if the purple flavor is too heavy, a small amount of yellow ink can be added to adjust it. Light blue is commonly used in spot color inks, which can eliminate the original brown background in black ink, making the black ink deeper and thicker.

3) Light color spot color ink deployment

The ink color matching that needs to be added with diluent or white ink is collectively called light color ink mixing. The method of adding a diluent to the primary color ink cannot be used for the preparation of light-colored ink, because the primary color ink has a strong color rendering ability in the diluent, and the coloring power of each primary color ink is different, which is easy to cause inaccurate hue and waste the primary ink. The correct blending method is to gradually add the primary color ink to the diluent, so that it is easy to control the change of the hue. After the hue meets the requirements, then expand the proportion of ink required for blending. [next]

4) Several points to be noted when mixing spot color ink

â‘  Take into account the characteristics of post-press processing. There are many surface treatment methods for packaging products, such as laminating, glazing, etc. After these surface treatments, printed products will have different degrees of hue changes and color density changes, so these situations should be considered when selecting inks. For example, if the printed product needs glazing, you can choose general ink. If you choose ink with good wear resistance, not only the cost is high, but also the glazing effect will be affected.

â‘¡ To see the color under the same light source, generally use the light source with a color temperature of 6500K as the inspection light source.

â‘¢Ink preparation is based on the principle of subtractive color method, so use as few primary colors as possible.

â‘£In addition to accurate hue, the printability of the ink is also important, such as adhesion, viscosity, emulsification, etc., sometimes a certain amount of additives are needed to change the printability of the ink.

⑤ The paper used for the preparation of spot color ink should be consistent with the printing paper to avoid color errors caused by different paper.

In short, spot color inks have higher requirements for color accuracy. Its qualification is not based on the approval of the deployment staff, but on the basis of customer satisfaction after the enlarged sample is printed in the printing plant. To master the preparation technology of spot color inks, it is necessary to accumulate more experience in practice.

Aluminum Foil has a clean, sanitary and shiny appearance, it can be integrated with many other packaging materials packaging materials, and aluminum foil surface printing effect is better than other materials.

Materials grade:8011-0,1100, 3102 ,1030B

Our Aluminium Foil products have the advantages of moisture-proof, air-tightness, light-shielding, wear-resistant, taste-preserving, non-toxic and odorless. The rolled surface of 8011 aluminium foil is flat, without holes, folding and brown oil spots.

Food usage:Baking, Wrapping,Roasting,For fridges,Grilling,BBQ,etc.

Users:Family,Restaurant,Fast food restaurant,hotel,Supermarket,etc.

Product form: foil,Foil Food Container.

Product name:High Quality Best Price Aluminum Foil.

Aluminum Foil

Food Use Aluminum Foil

Bbq Aluminum Foil,Aluminium Foil For Food,Food Use Aluminum Foil,Food Use Aluminum Foil