INDEX optical printing

In the case of paints and printing inks, the initial preparations will be in the semi-solid state because solvents are needed both in the process of dispersing the pigment in the paint or ink medium and for application purposes. These solvents dry out after the paint or ink is applied. When making coloured plastic articles, both heating and solvents may be used to aid dispersion in the plastic medium as part of the moulding process. However, from the viewpoint of the optical properties in all of these pigment uses, what is most important is that each of these media has a refractive index close to 1.5. 

Table VI gives, for a large group of sugars, a summary of the mutarotation constants and optical rotations measured at 0 and 20 in water or aqueous potassium hydrogen phthalate by Isbell and Pig-man. Most of the data were published in a circular now out of print Other compilations have been made by Hudson, Lowry, Osaka, Kendrew and Moelwyn-Hughes, Pratolongo (dilatometry and optical rotation, and Riiber and associates (dilatometry, refractive index, and polarimetry). " A considerable...

The objective to prepare reproducible pigments of predictable optical properties, consisting of uniform spheres can be, however, met by interacting soluble dyes with uniform spherical colloidal particles [21,44,45]. By selecting the cores of a given refractive index and diameter, it is possible to obtain colorants of different opacities and chromaticities and, thus, design them for specific applications, such as printing inks, color filters, cosmetics, etc. 

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