Search

The study on the method of the color measurement of gold and silver foil paper is important to control color quality in the printing industry. The methods used in the experiments were to study the role of the gold tone and silver tone by studying the influence of gold tone and silver tone with different content on the chromatic value of normal color ink with different tone and different saturation. In the experiments, chromatic value of SPIN and SPEX respectively in the diffuse light conditions of color measurement could represent the chromatic value of the ink containing gold or silver ink. Then the difference of L values between SPIN and SPEX was defined as lightness difference. The ratio of the difference of saturation between SPIN and SPEX to their sum was defined as saturation ratio. Therefore, the Correlation Properties between lightness difference and saturation ratio was quantified. The result shows that with the quantity of gold and silver ink increasing, saturation ratio has linear relation with lightness difference for the same color. Similarly, with the saturation of normal ink colors increasing, saturation ratio has linear relation with lightness difference for a series of colors containing the same quantity of gold and silver ink .

In order that a better analysis and evaluation of the color performance of developed color inks according to the printing requirements could be obtained, every ink will get abundant levels of ink supply amount made by double-channel control method. The max density obtained by the above method represents the color strength of inks. Then Color Management System is applied to building color gamut of matching process inks, and the color gamut represents the replicable color scope in practice. First, color strength of inks was identified by the following methods. Every ink was put respectively in two ink channels of the color printer and the total values of these two channels were applied to controlling the output, obtaining the wedge diagram of the multilevel output of ink supply amount. In the diagram, the max ink supply amount was large enough and the max density could represent the color strength. Because every ink needs a suitable range of the max density and needs to match the others well in practice. Referring to the standard of offset printing, a suitable density value for a certain ink was chose as its max ink supply amount. Second, within the range of the max ink supply amount, the data set of color patch in the characterization software of Color Management System was used to control ink supply amounts. The color patch was overprinted in the color sequences of Y, M, C and K, and ICC Profile was made according to the making process of standard Profile. Color gamut of the inks could be obtained from the Profile by using self-developed computing equipment and be compared with standard printing process. The result shows that the method used in the experiments is feasible and effective. In addition, the inks in the experiments have a large enough color strength and a color gamut satisfying the practical requirements of the color performance of inks in the printing industry.