Art Spectrum® Phthalo Blue is based on the Phthalocyanine pigment which is renowned for its tinting strength. It is the pigment which is produced in the highest volumes globally.
| Pigments | Lightfastness | Permanence | Transparent/Opaque |
| PB15:3 | ASTMI | **** (excellent) |
Transparent |
ASTM Approved Permanent Colours American Society for Testing and Materials, conforming to standard D4302-90.