Jetness, Blacks measurement

Jetness, Blackness value DIN 55979 light absorption of a carbon black paste in Unseed oil, determination by visual comparison against standard blacks or by measuring the absolute light remission (DIN)... 

H, Behrens F. Rossler, Tempera tur-messungen an Russ-strahlen in Flammed (Temperature measurements on jets of carbon black in flames), pp 610—13... 

Powder samples of 10u average diameter were prepared by air jet micronization of polymeric or composite chunks. Composite materials were prepared by melt mixing of polymer and carbon black. Carbon black was added to the surface by milling the polymer powder and carbon black with glass beads for an hour, and subsequently heating the particles to tack the carbon black to the particle surface. Static resistivity measurements were performed on packed powders in a procedure similar to ASTM D257. 

The My and hue values are derived from the CIELAB co-ordinate Yn, Xn, Zn and allows a numerical quantification of black jetness. This is only possible with the development of colour measurement equipment that can operate under reflection conditions of less than 1%. (Figure 3). 

A number of application test methods are discussed covering black jetness measurement, aluminium flake alignment and the usefulness of zeta potential is demonstrated in assessing dispersion stability. 

The nigrometer value characterizes the degree of blackness of paints or dyes. The nigrometer scale of carbon black is a measure of the mass tone or the intenseness of jetness or blackness and is closely related to the particle size thereof. In general the lower the... 

Jetness. This is a measure of blackness , expressed as a value (My). When carbon black is ground in linseed oil, a practised eye can distinguish up to 100 different levels of carbon black. Technical measurement techniques can also detect slight residual reflections. The current test uses a spectrophotometer. The smaller the particle size, the higher the My value. 

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