Spectroscopic and thermal properties of metallized azo dyes for digtital versatile disc-recordable

摘要

Three kinds of novel metallized azo dyes based on 4-methylthiazole, 5-methyl-3-isoxazole and 5-methyl-1,3,4-thiadiazole were synthesized in order to obtain a suitable optical recording medium for digital versatile disc-recordable(DVD-R). The absorption spectra, optical constants and thermal decomposition as well as red-light (650nm) static recording properties of three nickel-azo dye films were investigated. Particularly, the nickel-azo dye film based on 5-methyl-1,3,4-thiadiazole, peaking at 554nm and 602nm, with higher refractive index (n=2.41 ) and lower extinction coefficient (k=0.042) at the wavelength 650nm and a sharp threshold of thermal decomposition at 335°C was obtained. The results of the red-light(650nm) static optical recording test of this dye film indicated that higher reflectivity contrast of 35% can be obtained at a laser writing power of 7.5mW and pulse width of 200ns. These results imply the nickel-azo dye based on 5-methyl-1,3,4-thiadiazole is a promising candidate as a recording medium of DVD-R.