Most of the dtf printing process uses the four colors of C M Y K, but in order to meet the different needs of some customers, some customers want to show different colors on the clothes. At this time, spot colors must be used. So what is a spot color? This article will explain in detail.

What are spot colors?
Spot color means that when printing, the color is not synthesized by printing C, M, Y, and K four colors, but is printed with a specific ink.

Spot color ink
Spot color inks are pre-mixed by printing houses or produced by ink factories. For each spot color of printed matter, there is a special color plate corresponding to it when printing. Use spot colors for more accurate colors. Although the color cannot be accurately represented on the computer, the accurate color of the color on the paper can be seen through the pre-printed color sample card of the standard color matching system, such as the Pantone color matching system, which creates a very detailed color sample card .
For the non-standard spot color set in the design, the printing factory may not accurately adjust it, and the exact color cannot be seen on the screen, so if it is not for special needs, do not use the spot color you define easily.

Features of spot colors
1. Accuracy.
Each color registration has its own fixed hue, so it can ensure the accuracy of colors in printing, thus solving the problem of color transfer accuracy to a large extent.
2. Opacity.
Spot color ink is a kind of covering ink, which is opaque and can be covered on the spot.
3. Wide color gamut.
The color gamut in the spot color library is very wide, exceeding the performance gamut of RGB, not to mention the CMYK color space, so a large part of the colors cannot be presented with CMYK four-color printing inks.

Spot color printing
The ink formulated by spot color printing is obtained according to the principle of color subtractive color mixing, and its color lightness is low and saturation is high: spot color blocks with uniform ink color are usually printed on the spot, and the amount of ink should be increased appropriately , When the thickness of the ink layer on the layout is large, the sensitivity of the change of the ink layer thickness to the color change will be reduced, so it is easier to obtain a uniform and thick printing effect.

The color block overprinted by four-color printing process, because the various colors that make up the color block are mostly composed of a certain proportion of dots, when printing dots, the thickness of the ink layer must be strictly controlled, and it is easy to change due to changes in the thickness of the ink layer and printing. Changes in process conditions cause changes in color intensity. A change in dot gain, resulting in a color change. Moreover, since the change of any color that makes up the color block will lead to the change of the color of the color block, the chance of uneven ink color will be multiplied, so it is not easy to obtain the ink color of the color block overprinted by four-color printing uniform effect. If the color of the color block cannot be overprinted at one time with a multi-color machine, it is easy to cause color shift due to the difficulty in controlling the color of the semi-finished product. In addition, four-color printing obtains the comprehensive effect of subtractive color absorption and additive color mixing of dots. The color block has higher lightness and lower saturation. For light color blocks, four-color printing process is adopted. Due to the low coverage of the ink on the paper, the ink color is flat and lacks a thick feeling. Due to the relationship between the dot angle, it is inevitable that people will feel the existence of the pattern.

Color matching method
1. Empirical color matching method. The empirical color matching method refers to the color matching based on the experience and feeling of the color matcher without a color measuring instrument. The early stage is based on the experience accumulated by the color matcher from practice, and the color matching in the middle and late stages is based on 10 basic color maps. Or printed color spectrum as a reference standard for visual color measurement. The empirical color matching method is often affected by the physiological and psychological factors of the color matcher and other objective conditions, and the product quality is difficult to maintain stability. In addition, relying on experience and feeling color matching can only be qualitative, not quantitative, and it is difficult to disseminate and communicate technology.

2. Mechanical color matching method. The mechanical color matching method is a relatively advanced color matching method that has gradually become popular in modern times. In each link of color matching, certain machinery and instruments are used as configuration and measurement tools. carried out within the range. This method changes some of the blindness of color matching in the past experience, and improves the speed and quality of color matching, but the accuracy of color matching is low and the error is large.

3. Computer color matching method. Computer color matching has a history of about 30 years abroad, and has been applied in many color-using departments at home and abroad. People use the connection between the color database stored in the computer and the relevant color matching software to analyze and process the color data on the sample, and through calculation, correction, and color adjustment, select the color formula that suits the requirements of the sample, and then complete the automatic printing of ink. color matching. Computer color matching requires standard color samples and the color of the prepared ink samples to be expressed in numbers, which ensures the accuracy and uniformity of each color matching, and greatly saves the color matching time. Convenience, speed, rapidity and accuracy are the advantages of computer color matching . However, the color matching software developed by different enterprises and companies are all developed on the basis of considering their actual production and application conditions, and there is no unified standard, which is one of the reasons why computer color matching cannot be popularized.

Recommendations when making spot colors
In the process of making spot colors, reducing 1-2 pixels will make the overall sense of the picture better.

The A3 dtf printer(DTF-A30)  independently developed by TEXTEK provides 3 spot colors, w and 2 fluorescent colors.

What are the benefits of spot colors?
It can meet the printing methods in different forms and has more application schemes. Spot colors are often used in screen printing. They provide an exact match, so they are a good choice when you want perfect color reproduction on different materials and substrates. Spot color printing is slightly different than four-color or CMYK printing. With spot color printing, each color is mixed and printed individually. Instead of recreating a color using CMYK shades, spot color printing utilizes an exact match to the original PMS or Pantone matching system color.

How to set spot color in different RIP software?
How do we set the spot color? See the following documents for details.
RIP transparent image output-instruction book

TEXTEK's business covers many countries around the world, including emerging markets and mature markets. We have a complete sales system and are committed to using our professional knowledge and first-class service to help customers improve their digital printing business.