Pigment Red 170 F5RK P.R.170 provides medium shades of red, which in tints are somewhat bluish. The transparent type is preferred for printing inks. It is tinctorially very strong and lends itself to use in a variety of high grade formulations. Inks formulated at only 15% pigment concentration will under standardized conditions produce 1/1 SD letterpress proof prints; the resulting prints are very lightfast. As a result of its excellent fastness properties,  The plastics industry uses P.R.170 almost exclusively to color rigid PVC. P.R.170 is also very heat stable; it retains its color strength for 10 minutes at 200°C or for 30 minutes at 180°C, which makes it a valuable pigment for metal deco printing. P.R.170 is also found in decorative printing inks for polyester films.