Color purity

Perylene (199) and its derivative (TBP, 200) have been widely used as blue dopant materials owing to their excellent color purity and stability. Efficient blue emitters with excellent CIE coordinates are found in biaryl compound 2,2 -bistriphenylenyl (BTP, 201) as shown in Scheme 3.62 [145]. A device of structure ITO/TPD/BTP/TPBI/Mg Ag emits bright blue emission with CIE (0.14, 0.11). A maximum brightness of 21,200 cd/m2 at 13.5 V with a maximum EQE of 4.2% (4.0 cd/A) and a power efficiency of 2.5 lm/W have been achieved. 

The presence of incandescent solid or liquid particles in the flame will adversely affect color quality. The resulting "black body" emission of white light will enhance overall emission intensity, but the color quality will be lessened. A "washed out" color will be perceived by viewers. The use of magnesium or aluminum metal in color compositions will yield high flame temperatures and high overall intensity, but broad emission from incandescent magnesium oxide or aluminum oxide products may lower color purity. 

High luminous intensity color purity produced by flames resulting from the combustion of Group II perchlorates mixed with alcohols or other org solvents was noted in a previous study made to adapt these mixes to markers flares for aerial use. Tried to improve Marine MK2-0 Marker but concluded that no improvement is possible unless MK2-0 is redesigned (Ref 7)... 

Intensity is the response of the human brain to color purity. The purist colors are said to have the highest intensity. A colored laser light has high intensity. All of the light waves reaching the retina are of the same wavelength. 

Wheat starch possesses a unique combination of properties that is important to its utilization in various food and industrial products. Those properties are related to its color, purity, flavor, paste viscosity, paste clarity, paste texture and gel strength.27 28,311-315... 

The strontium formulation shows a reasonably high red color purity as can be seen from the chromaticity diagram in Fig. 2.19a. The color purity (pe) of a visible flare with the chromaticity (x, y) is its difference from the illuminant s white point relative to the furthest point on the chromaticity diagram with the same hue (dominant wavelength for monochromatic sources) where (x , y ) is the chromaticity of the white point and (x7, y7) is the point on the perimeter whose line segment to the white point contains the chromaticity of the stimulus. 

The color purity is the relative distance from the white point. Contours of constant purity can be found by shrinking the spectral locus about the white point. The points along the line segment have the same hue, with pe increasing from 0 to 1 between the white point and position on the spectral locus (position of the color on the horseshoe shape in the diagram) or (as at the saturated end of the line shown in the diagram) position on the line of purples. 

A breakthrough discovery was reported by Sabatini (ARDEC) in the area of green illuminants. Formulations without any heavy metal can be based on boron carbide (B4C, fuel) with a suitable oxidizer (e.g. Iboron carbide (B4C) in pyrotechnical compositions. It can be seen that flares with 100% boron carbide as fuel show longer burn times and higher luminous intensity than the control barium nitrate based flare (M125 Al) while the spectral (color) purity is slightly lower. 

Fluorene copolymers, (III), were prepared by Sohn [3] that offered improved emission efficiency and blue light color purity and were used in organo-electroluminescent devices. 

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