Pigment & Material
Azo pigment family (PR9, PR112, PR170). Range from warm orange-red to cool blue-red. Good lightfastness. More affordable and less toxic than cadmium reds. Now the most common red pigment in student-grade paints.
Origin & History
Naphthol reds are a family of synthetic organic pigments developed in the early 20th century as the first viable replacements for cadmium red. Named after naphthol (beta-naphthol), the chemical precursor used in their synthesis.
Psychology
Naphthol reds sit between cadmium red and alizarin crimson — warm and opaque but with more subtlety than cadmium. They are workhorse reds: reliable, versatile, uncomplicated.
In Culture
The introduction of naphthol reds democratised artist painting — suddenly vibrant, reasonably permanent reds became affordable. This contributed significantly to the explosion of amateur and hobby painting in the mid-20th century.