Spot color ink

Spot color ink refers to a pre-mixed good specific color ink, such as fluorescent yellow, pearl blue, metal gold silver ink, it is not CMYK four colors mixed out, spot color means the exact color.

1.peculiarity

(1) accuracy

Each spot color 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) the field sex

Spot colors are generally defined by solid colors, no matter how light they may be. Of course, also can give spot color plus net (Tint), in order to present spot color of any depth tone.

Opacity

Spot color ink is a kind of covering nature of ink, it is not transparent, can be field coverage.

Display gamut width

The color gamut in the spot color inventory is very wide, exceeding the RGB performance gamut, not to mention the CMYK color space, so, a large part of the color can not be rendered with CMYK four-color printing ink.

2.mix of base

Spot - color ink generally refers to the ink manufacturers produce a series of varieties other than all kinds of color ink. The effect of allocation is closely related to the experience of the operators, and the requirements for the operators' color technology are particularly high, so they must have a certain knowledge of ink color science.

Basic color ink

The basic color ink is divided into three types according to the mixing method: the original color ink, the standard color ink and the standard multi-color ink.

Primary inks: primary inks that cannot be mixed with other colors.

Such as yellow, magenta, cyan ink. The three primary colors of ink, in theory, according to different proportions and ways of mixing, can be allocated to a variety of different colors, but in practice, no matter how to mix can not match a pure black. Therefore, in color printing, mostly using yellow, magenta, green, black four color ink to overprint black.

In addition, different countries and manufacturers of four-color ink standards are not the same, such as China's offset light fast dry four-color ink color designated for yellow, magenta, sky blue and black.

Standard inks: inks of any two primary colors mixed in equal amounts.

Standard polychromatic ink: refers to any color ink in which two colors are mixed equally or three primary colors are mixed in different proportions.

Dark spot ink allocation

With a kind of and several kinds of original ink, do not add any diluent for the combination of color is collectively referred to as the allocation of dark spot ink.

According to the principle of subtractive method, allocation of dark ink should be as little as possible with the number of the original color ink. Otherwise it will reduce the brightness of ink and color brightness. But some products have special requirements for ink, such as dark brown ink with red ink, yellow ink and a small amount of black ink mix.

Additional, the complex color such as the bronze that mixes with the 3 primary colors with different proportion, red violet, olive green differ in depth, must use complementary color theory to correct its slant color.

Green phase is too heavy, you can add a little red ink to correct;

Red phase is too heavy, can add a small amount of blue ink to correct;

Purple flavor is too heavy, can add a little yellow ink to correct;

To deepen the concentration of black ink, you can add a small amount of dark red, light blue to adjust.

As in offsctdruckeren production of black ink, with light blue, fast bright red, phthalein blue and other pigments to adjust the principle of black ink phase.

Light blue is commonly used in spot ink, it can eliminate the original brown black ink, black ink deeper, more concentrated.

The allocation of light-colored spot ink

Where the need to add diluent or white ink for the allocation of ink color collectively called light ink allocation. Allocation of light color spot ink can not be used in the original color ink add diluent method, because the original color ink in the diluent color ability is strong, and the original color ink coloring force is different, easy to cause color phase and waste of the original ink.

The correct allocation method is to use in the diluent gradually add the original color ink, to meet the requirements of the color phase, then expand the proportion of the allocation of ink. Light color ink can be divided into three types:

Diluent based dilute ink: it has a certain degree of transparency, suitable for ink multi - color overprint.

With white ink - based matte ink: with a strong covering power, ink color more bright. General synthetic paper with light ink are white ink.

With diluent and white ink mixed with the allocation of light ink.

3.Blending method

(1) proportion method

Ink color allocation first to carefully observe, analysis of ink sample or printing sample. The ink sample can be a scraping sample on Daolin paper or an IGT printer. Then to observe, analyze the impression may be composed of several colors of ink, with a scale of copper ink suction tube, in proportion to the rough adjustment.

To see the rough ink sample (scraping) and the standard sample is close, and record the ink ratio and ink volume. If it is close, convert the proportion into percentage, and then use the analytical balance for fine adjustment. If not close, should change the proportion of each color ink, continue to allocate.

(2) the reduction method

Established standard sample (sample the standard color provided by the customer or not close to standard sample ink sample) is composed of which a few color printing ink, find out the ink contained, with vegetable parchment said 10 g or 5 g on the glass plate, any ink used to be obtained, when the ink is close to standard sample, sample available a little ink blade, observe complexion, background, when the blade used in printing ink to recover.

If close to the standard sample, weigh the remaining ink can be converted to the spot color ink percentage content, and then fine adjustment with a balance.

(3) the PANTONE color matching method

PAN TONEFormula Guide's Pantone Color Matching Guide is the universal color Guide in the world. It provides each color standard with number and ink blending ratio. It adopts fan-shaped binding to make color selection fast and convenient.

For Pantone spot color ink, carefully observe and analyze the printing sample, and compare with the color sample in Pantone color matching guide to find out the similar color sample. If it is very close, write down the color sequence number and compare the printing sample in the ink color matching guide to analyze whether the two color matching guide prints are consistent;

If there is an error to find out the error is caused by which ratio of ink. After analysis, the proportion of the printing ink can be adjusted. This makes the deployment relatively easy.

4.The main points of mix

The operation flow of special color ink. Ink allocation should pay attention to the following points:

(1) take into account the characteristics of post-press processing

Choice of ink, to consider the processing after printing, such as: printing products need to polish, choose general ink, if the choice of frictional good ink, not only high cost, but also affect the effect of glazing.

(2) Like mingles with like

Ink of mixing together should try to master the same type mixing principle, such as deployment of three and multicolor, without offset printing light quick-drying inks, can be used offset printing ink instead of resin type, but should pay attention to spelling mix proportion, if too much offset printing ink resin, to offset the light will affect the characteristics of the quick dry ink can not meet the purpose of improving the quality of the calendar.

Ink color knowledge tells us that the more varieties of ink mix, the darker the color. Therefore, can use the original color ink, never use color ink; Do not use polychromatic ink if it can be used.

(3) determine the basic ink

The color of the impression needs more than two ink mix, to determine which color as the basic ink, gradually add other ink; If with light color ink as the basic ink, gradually add dark ink. This ink volume will not be too much.

The print density is consistent

When mixing colors according to the impression, the ink should be adjusted during the printing so that it is consistent with the density of the impression.

Pay attention to recording and calculation

In particular, according to the scale method to adjust spot ink, to record the amount of ink added, the remaining amount of ink, which is conducive to the calculation of the final ratio.

Adjust ink

In the allocation of spot color ink, in addition to color, sometimes need to add a certain amount of additives, to change the ink to meet customer needs.

Pay attention to the printing mode and characteristics

When mixing ink color, should consider the printing method and characteristics, clear ink is used for what kind of printing, letterpress or lithography, printing field or printing wire.

Because different printing methods form ink layer thickness is different, the color is also different.

For example: for printing ink based on the screen, in the color can be focused on the same background color; If it is based on the field, the color can be focused on the same complexion; If it is both sometimes, the background color and the complexion should be both.

Consistency of paper

The allocation of spot ink paper and printing paper to keep consistent, to avoid the color error caused by different paper.

Pet-type printing is consistent in time

When the ink sample provided by the customer is used as the standard sample to mix spot color, the standard sample and sample should be compared simultaneously, so as to accurately judge the color difference between them.

The suicide weighing is accurate

Mix the color to find out the preliminary ratio, must use the balance fine adjustment, so as to ensure the minor sample (5G), enlarged sample (100-2000g), production sample color consistent. And pay attention to mixing well.

Spot color ink generally requires a higher accuracy of color, its eligibility, not to the deployment of personnel approval as a benchmark, but to enlarge the sample printed in the printing plant, customer satisfaction as a benchmark, or through the color measurement instrument measurement confirmation.