European Color Scale

P.Y.171 was found in the Japanese market. Its prints are considerably redder than those made from P.Y.l 3 besides, its color is off the fastness limits for yellows on the European color scales for offset and letterpress application. P.Y.171 has a dull hue and is weaker than P.Y.13. The pigment is targeted for the coloration of plastics, such as PVC and PE. 

P.R.184 affords a red which is somewhat on the bluish side of P.R.146, to which it is closely related in terms of chemical constitution. Both products also behave very similarly in application. Their prints are fast to soap, butter, paraffin, dibutyl phthalate, white spirit, and toluene. P.R.184 produces a shade which matches that of the standard magenta for multicolor printing on the European Color Scale CIE 12-66. This shade results from formulating an ink at 15% pigment concentration and printing the ink in a standard layer (1 pm). 

The printing inks industry uses P.B.15 3 especially as a blue component on different color scales for three and four color printing. The pigment corresponds to the CIE12-66 standard shade of cyan on the European Color Scale for offset and letterpress prints (Sec. 1.8.1.1). 

P.Y.12 has a medium yellow hue, which is used to a large extent in letterpress and offset printing inks as the yellow component in three and four color printing. To adjust P.Y.12 to the standard yellow of the European standard (Sec. 1.8.1.1), the hue may be shaded with traces of a redder component, such as one of the orange pigments P.O.13 or 34. No such shading is necessary for P.Y.12 to match the yellow on the Kodak scale. 

British suspended particulate sampler In recent years the old British standard method has been super-ceded by European directives such as EN12341 Air Quality - Field test procedure to demonstrate reference equivalence of sampling methods for the PMIO fraction of particulate matter. The determination of smaller size fractions (PM2.5) is also covered by a further directive. The US EPA have similar standard reference methods for particulate material (USEPA 40 CFR part 50). An early method was to simply compare the color of a filter paper through which a volume of air was drawn to an incremental gray scale (16 shades from white to black) this was then converted into an integrated particle loading with reference to the size cut-off offered by the pore size of the filter used. This was known as the black smoke index method. 

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