R., G. Rao
2017
Citations
0
Influential Citations
4
Citations
Journal
Asian Journal of Chemistry
Abstract
Colourants are characterized [1-3] by their ability to absorb light selectively in the visible region (380-780 nm). Electronic (absorption and reflection) spectra have been used to investigate some corrections between chemical structure and colour of the species. The characteristic parameters of the spectrum, i.e. the positions of absorption bands and their intensity and shape are important factors in the determination and prediction of colour [4] and these parameters are dependent upon the electronic structure and symmetry of the clues. Theoretical problems connected with the nature of colour have been studied extensively, especially in case of the organic dyes. One of the most important problems in colour technology is how to attain a specified colour using a mixture of colourants [5]. A tristimulus colorimetry is generally employed for colour measurement. The principle of operation involves projection of light of a known spectral energy on the pellet and measurement of the intensity of the reflected light using photo detectors. All the synthesized pigment samples are found to be having colour coordinates and exhibit the colour from pale yellow to orange red. Reflectance spectra of the samples show high reflectance percentage in the 600-800 nm range. Because of the homogeneity of the phase formed the intense colouration the yttrium doped pigments have been found to be superior to cerium doped pigments as possible ecological inorganic pigments. Synthesis and Characterization of Orange Pigments from Rare Earth Metal Ions