The Contribution of Co~(2+) to Blue Color of Synthetic Spinel

摘要

Through to 110 pieces purity transparent and color uniform, 3 × 5 × 7mm blue synthetic spinel made with the flame fusion method on chemical compositions and color parameter measurement the Co~(2+) content and color changes, clear the influence on Co~(2+) relationship of blue synthetic spinels' color appearance. Through LA-ICP-MS to analysis the cause of colorant content, proof that with Co~(2+), the increase of the content of synthetic spinel will shift blue to purple tone, and C~* shows a parabola form with the drop of L~*, 700 ppm ～ 900 ppm place in peak. ΔL* ∈ (3.55 ～ 76.94) with Co~(2+) e (4.59 ppm ～ 1849 ppm) change the largest amount, ΔC~* ∈ (-9.99 ～ 29.32) next, ΔH~* ∈ (-20.34 ～ 4.67) compared with before two changes smallest. Co~(2+) content in l00ppm below, blue color of synthetic spinel with Co~(2+) content increased changes greatly; 500 ～1500 ppm, visually achieve optimal color (C~* higher); above 1500ppm, because of the Co~(2+) overmuch make the color burn cause the overall decline of transparency, the change of L tends to be gentle, C decrease obviously. Use Color i5 in standard color measurement instrument lighting source D65, measured the lightness L~* specimen Color a and b , chroma C and tonal angle h_o, based on the uniform color space CIE 1976 L~*a~*b~*, in lightness minimum L 9-10 specimen (processing data for standard to 9th), with the help of DE2000 benchmark for calculating formulas, the Color, the color difference train E~* by partial correlation analysis card clearly degrees of off color changes L~* has certain influence on rΔl~*'×Δe~* = 0.996, while rΔc~*×ΔE~*= -0.427, rΔH~*×ΔE~* = -0.339. Conclusion, the bule color of synthetic spinel because of its Co~(2+) content changes main influencing L~* to contribute to its color appearance.