In some printed products such as trademarks, certificates, packaging, etc., customers sometimes have high requirements for a specific color, and this color is overprinted with four colors of cyan, magenta, yellow, and black, or often because of one of them. The amount of ink in each color changes, so that the printed color also changes; or the target color cannot be printed at all. In this case, in order to ensure the stability of printing quality and anti-counterfeiting requirements, customers often require the use of spot color printing. The so-called spot color printing refers to printing inks prepared by a certain proportion of color inks according to a certain ratio according to the colors specified by the customer, and printed on the printing machine at once. Because this color is pre-modulated by the printing plant according to the color characteristic values ​​such as the hue and brightness (whiteness) of the target color specified by the customer, and it is printed on the spot again, it has no jagged interference of the printing dots and the edges are neat Stable color appearance. For example, the big red on the trademark of Beijing Red Star Erguotou Liquor was printed by spot color printing.
Obviously, the key to spot color printing is not printing, but color matching. Today's color printing companies generally set up special personnel or departments to engage in artificial color matching. Manual color matching is based on the visual inspection and experience of workers. Some spot colors require multiple adjustments for a long time, which takes time and effort, greatly increasing production costs, and is a relatively backward color matching method. At the same time, the brand, model, production batch of the ink used, the whiteness and color of the paper, and the pressure and speed of printing all have an impact on the accuracy of the spot color ink preparation.
With the continuous development of computer technology, in order to solve the above problems, computer color matching has gradually entered people's field of vision and attracted much attention. In the printing, printing and dyeing, paint, coating and other industries, there are research and development institutions engaged in computer color matching at home and abroad. However, the current computer printing ink color matching system is often based on a certain brand of ink. It takes many years to establish a basic ink database. The workload is large and the capital investment is unimaginable. Therefore, the price of its products must be high, and it has stricter requirements on the choice of ink brands, which has virtually increased the production costs of enterprises.
In order to make computer color matching technology popularized in the printing industry as soon as possible, with the purpose of serving printing companies, with the purpose of reducing production costs and improving work efficiency, China ’s printing science and technology research is based on the independent innovation of the complex spectrum chromaticity theory, after years of research , Developed a simple and easy "CFS complex spectrum ink color matching system".
Modern color science theory was founded in the 19th century. By the 1920s, many scientists had chosen three wavelengths of red, green, and blue monochromatic lights for matching experiments, and proved that any natural light color can be matched with these three basic colors. On this basis, the International Commission on Illumination (CIE) launched the "standard chromaticity observer XYZ tristimulus value" in 1931, laying the foundation for today's CIE chromaticity theory.
The theory of complex spectrum chromaticity is based on the volatility and quantum nature of light, based on the integral transformation formula of neural signals, the wave equation of electromagnetic waves, and the photon momentum formula of Einstein, to derive the pure physical concept from light to color Calculation formula of complex spectrum chromaticity. A detailed discussion of the complex spectrum chromaticity theory-"Analysis of the Physical Color of the Complex Spectrum of Light and Color Transformation" was published in the fourth issue of the Journal of Beijing Institute of Printing Technology in 2007.
According to the new theory of complex spectral chromaticity of light-color conversion, the two-dimensional complex spectral chromaticity diagram is used to replace the three-dimensional color space of CIE chromaticity theory. At the same time as the value, the main frequency, hue, color intensity, whiteness (color balance) and other new color characteristic values ​​are also given. The hue of the color corresponds to the frequency of light on the complex spectrum; the brightness of the color corresponds to the area surrounded by the sagittal curve on the complex spectrum, which corresponds to the energy of the light; the color intensity of the color corresponds to the momentum of the photon; the color of the color The degree of balance corresponds to the white light content in the total light quantity of the complex spectrum. To evaluate colors with complex spectrum chromaticity, neither CIE tristimulus values ​​nor red, green, and blue color filters are used.
The complex spectrum color measurement method is physical, and the evaluation is objective, which is conducive to the establishment of a completely objective physical color evaluation system.
In the natural world, there are five colors and thousands of purples and reds. The color matching is to select only a few or even a dozen colors as the basic colors, and use them to match each other to modulate a specific color. However, because printing ink belongs to reflective color development, not just any color can be used as a basic color. The conditions suitable for basic colors are: â‘ wide color gamut and high reflectivity; â‘¡ two basic colors adjacent to the hue must have a wider common response frequency domain; â‘¢ have a higher color intensity, in its The lower the complementary color gamut, the better; â‘£ The red, green, cyan, and blue color areas of the complex spectrum should be reasonably distributed. Two adjacent basic colors should neither be too close nor too far away.
Theoretical innovation will inevitably bring about technological progress. The CFS complex spectrum ink color matching system has a powerful, fast, and wide-ranging printing ink color matching engine. It is based on the basic color ink database independently established by the company. Through the measurement of the target color, combined with the price and inventory of the company's basic color ink, it uses "quick color matching", "precision color matching", "strict color matching" and so on. A variety of color matching methods, giving "best hue" and "lowest cost" and other sets of color matching schemes, freeing companies from complicated and expensive trial and error, greatly reducing the company's production costs. The characteristics of CFS complex spectrum ink color matching system are:
• It has nothing to do with the ink brand-based on a brand new theory and using scientific calculation methods, the color matching system is adapted to the common printing inks of the company as much as possible.
• Reduce the cost of printing production-with an accurate and fast color matching engine, which frees enterprises from complicated and expensive trial and error.
• Newly added color difference content-in addition to providing ΔE, there are more specific and calculable hue difference ΔH, brightness difference ΔL, and color saturation difference ΔS.
• Unique color difference correction scheme——According to the measured and calculated color difference parameters, an operable color difference correction scheme is provided.
The advantages of computer color matching are economic, fast and accurate, which is incomparable with artificial color matching. The CFS complex spectrum ink color matching system developed by the China Institute of Printing Science and Technology is theoretically innovative; the calculation method has obtained the national invention patent and is accurate and reliable; the operation method is in line with the usage habits of Chinese users; the price is reasonable.
Stackable Shoe Box,Plastic Shoe Box,Transparent Storage Box,Dust Proof Shoe Box
Taizhou Baiying Commdity Co., Ltd , https://www.baiyingplastics.com