Heat resistance selection of color and model. Because some colors are not resistant to water boiling, it is easy to see color exudation when water boiling. Gold and silver ink should be used with caution, and is generally not recommended for cooking. As gold and silver powder are all metal products, the content of heavy metals and the adhesion of gold, silver and ink should be considered after boiling. The film should have good ink adhesion fastness, so as to ensure the peeling strength of the Z end of the ink position. There shall be no penetration and transfer of plastic film. The ink used for water boiling and cooking must also have the corresponding temperature resistance and excellent adhesion fastness. The white and light yellow ink has the following three problems:
1) Improve ink color concentration; High color concentration, less solvent, fast drying, easy to make blocking, poor leveling and pulverization.
2) Ensure that the ink layer thickness reaches the standard; Ink transfer rate -- the quality of printing plate holes, printing pressure, film surface treatment and static electricity.
3) Control the dispersion of pigment; It depends on the ratio of refractive index of pigment to that of binder. Polyketone resin
The Lambert Beer law that we know is derived under ideal conditions. We know that it is impossible in real life but under completely ideal calculation conditions. This law only considers the absorption of ink, and does not take into account many factors in the actual printing process, not to mention the impact of substrate paper, plastic, etc. on ink transfer and color formation. Therefore, there is a difference between the theoretical calculation and the actual densitometer or colorimeter measurement results. However, although the actual situation is very different and there are many kinds of influencing factors, "absorbency" is still the fundamental reason for the ink color. The above is an introduction to the method of ink thickness calculation, which is expected to be a reference for relevant operators in the industry.