2) At present, all products of Yunyin are combined printing. Because combined printing cannot take into account the color requirements and adjustment of a single customer, generally, combined printing will have a printing color difference of about 10%, even if it is the same. The printed documents are of the same printing paper quality, and there will be some color differences in each batch.

3) During the printing process, the drying speed of the ink will be affected by the surrounding environment such as temperature and humidity. Therefore, different batches of printed products will vary due to changes in the environment in the printing workshop at different time periods. For plate printing, the same document may be printed several times before and after it will have a certain probability of different color shades.

4) Different papers have different color rendering effects. The same printed document is printed on different materials, such as coated paper or rigid ancient paper, which will cause different printing effects and color. This is a physical property of the material. Colored paper (such as yellow kraft paper), of course, there will be greater color difference; In addition, post-processing on the paper, such as bright film or matte film, will also affect the color.