Blockx Soft Pastels are handmade in Belgium using pure pigments in the same tradition started by company founder and chemist Jacques Blockx in 1844. Pastels are soft and velvety in texture. Best-suited for use on pastel paper.
Color Swatch created using heavy to light application and was applied on 100 lb (163 gsm) drawing paper material.
Bis-(p-chrolopheny)-1. 4-diketopyrrolo(3. 4-c)pyrrole
Pyrrole Red is opaque and has strong covering power. According to manufacturer Ciba, which uses the trade name Irgazin Red, it is a “clean, highly saturated mid shade red with high temperature resistance, excellent color strength, outstanding chemical, solvent and bleed resistance, and good weatherfastness.”
Pyrrole Red is considered to have excellent lightfastness among organic pigments in its class. Tests in industrial applications have given it scores of 7-8 on the Blue Wool Scale.
According to the Australian government's Ministry on Health and Aging, "The notified chemical exhibited low oral and dermal toxicity in rats, did not exhibit toxic effects when administered orally to rats for 28 days, was not a skin irritant in rabbits, was not a skin sensitiser in guinea pigs, was not mutagenic in bacteria and was not clastogenic in CHO cells in culture. However, the notified chemical was a slight eye irritant in rabbits. On the basis of submitted data, the notified chemical would not be classsified as hazardous in accordance with Approved Criteria for Classifying Hazardous Substances."
Pyrrole Red, used as an automotive paint and as a colorant in plastics, was developed as one of a range of pigments to replace lead based pigments. In art materials, it is often used as a synthetic and lightfast replacement for carmine, a laked pigment that was originally produced from the body of the cochineal insect. It is also used to replace the older naphthol reds, organic red pigments that are sometimes only marginally lightfast and weatherfast.
Magnacryl Red, Versal Red, Microlith Red, Unisphere Red, Cromophtol Red, Irgazin Red.
1,4-diketo-3,6-di(4'-tertiary butyl phenyl)-2,5-dihydro pyrrolo[3,4-c]pyrrole
This bluish red transparent pigment has high tinting strength. Diketo pyrrolo pyrrole pigments are noteworthy for their light stability, excellent weatherability, and outstanding heat stability.
Pyrrole Rubine has excellent permanence and lightfastness for an organic pigment in its color range.
Pyrrole pigments are considered to be non-toxic.
The Pyrrole group of synthetic organic pigments was developed in the 1980s. Pyrrole Rubine was first manufactured by Ciba Specialty Chemicals under the trade name Irgazine Ruby. Although not a perfect match for alizarin crimson, Pyrrole Rubine is one of several new pigments that has helped to close a traditional gap in the gamut of artist pigments, the lack of lightfast and transparent colors in the red/blue and red/violet parts of the spectrum.
® Blockx is a registered trademark.