In color prints, more colorful and natural color reproduction can be realized by combining special colors (hifi colors) of red, green and blue, with four colors including three primary colors of cyan, magenta and yellow, plus black.
However, as the number of colors is increased, the number of patterns of combinations of color ink for finding out the target color also increases. Therefore, in a simple method, such as conventional UCR and UCA, there have been problems that continuity of gradation tends to be lost and the method is easily influenced by fluctuation of each equipment. In Konica Minolta, we noticed color reproduction by multicolor from way back, and have studied methods to realize smooth gradation while realizing a wide color area (area of reproducible colors) by controlling these colors properly.
We have developed color management software in which combination patterns of various types of color ink leading to the same color reproduction results are calculated, and the best combination of color ink for reproducing smooth gradation can be obtained, according to characteristics of the equipment. Thus, it has become possible to conduct measurement of equipment characteristics up to color reproduction in a consistent process. This color management technology is now active in inkjet textile printers.
- UCR: “Under Color Removal” is a method to replace a gray portion where three colors of cyan, magenta and yellow are superposed with black.
- UCA: “Under Color Addition” is a method to add black to each color component of cyan, magenta and yellow in the shadow portion.