Phthalocyanine Blue (Green Shade)
Colour Number: 22
Pigment Details: Beta (β) – Copper Phthalocyanine / Colour Index Pigment Blue 15:4 (C.I. PB15:4)
Phthalocyanine Blue (Green Shade) Professional Watercolour is prepared using the synthetic aromatic macrocyclic organo-metallic pigment, β-copper phthalocyanine. The pigment has been selected for its purity, light fastness and intense green shade blue hue, making it ideal for use in A J Ludlow’s Professional watercolour range.
Commercially, the more stable β-copper phthalocyanine is easily converted from the α-form. Although both are formed of the planner copper-phthalocyanine complex, the crystal shape and structure is markedly different; the β-form is composed of a tightly packed herringbone structure, where the copper atom has octahedral geometry, resulting in rod shaped crystals, whilst the α-form is composed of a relatively more open crystal lattice, where the copper atom has square geometry and tends to form block crystals. This difference in crystal packing is the reason for the shift in colour and also why the α-form is less stable.
The greenish β-copper phthalocyanine is a very good clean transparent blue and can be used on the artist’s pallet as a cool primary blue. A J Ludlow’s Phthalocyanine Blue (Green Shade) Professional Watercolour has a high tinting strength and so is best used sparingly when initially mixing with other colours.
|Brand||A J Ludlow|