A J Ludlow Quinophthalone Yellow Professional Watercolour

Quinophthalone Yellow is just one of the bright and exquisite Professional Watercolours from A J Ludlow. This Special Limited Edition watercolour has excellent permanence and light fastness, ensuring that the watercolour’s properties are exceptional. As with all our fine-art materials, Quinophthalone Yellow watercolour is lovingly handmade in the UK by a skilled artisan from the best ingredients and finest pigments.

Quinophthalone Yellow professional quality watercolour is supplied in a 15ml glass jar, because:

The watercolour’s wet mass tone can be seen through the walls of the jar;

The colour can be easily transferred from the jar to the palette with a palette knife.

But more importantly, there is no need for unnecessary additives or formulation changes to make processing in our colour manufacturing workshop easier, allowing the Quinophthalone Yellow watercolour made by A J Ludlow, to be at the highest pigment concentration and the pigment’s unique properties to be uncompromised. Anything less would be at odds with the brilliance and performance demanded of a professional quality watercolour range.

This Professional Watercolour is prepared using the synthetic polycyclic organic pigment derived from quinophthalone. The pigment has been selected for its purity, high tinctorial strength, transparency, exceptional light fastness and very attractive, mid-shade yellow colour. It affords a transparent watercolour (as can be seen in the figure 1a below).

Figure 1: Assessment of (a) the opacity/transparency and (b) staining power of A J Ludlow Quinophthalone Yellow Professional Watercolour*.

The Quinophthalone Yellow watercolour does not lift out completely (as can be seen in figure 1b above) and so has a propensity to stain the watercolour paper.

This watercolour has a structured consistency, but is easily transferred from the jar to the watercolour palette using a clean spatula or palette knife. As with all the Professional Watercolours from A J Ludlow, once water is added, this watercolour has excellent flow and is a joy to paint with.

Quinophthalone Yellow is a bright and intense Professional Watercolour with excellent tinctorial strength. It has a warm yellow mass tone, but cool green-shade undertone. In this respect when used in colour mixes, it creates a variety of bright secondary colours. When mixed with other transparent watercolours the mass tones of these secondary hues will also be much deeper than those created from the more opaque cadmium yellows in the A J Ludlow Professional Watercolour range, thus securing it a special place on the artists’ watercolour palette.

First synthesised in 1882 from quinoline bases (derived from coal tar) fused with phthalic anahydride, quinophthalone was initially used as the basis of anionic and cationic dyes. By halogenating the quinophthalone, pigments were produced in the yellow to red colour space, which proved to be more commercially significant (from “Pigment Compendium”, page 310).The pigment’s opacity has been found to be dependent on the pigment’s shade; the greener yellows are transparent, whilst the redder ones are opaque.

Pigment Details: Chlorine-substituted Quinophthalone / Colour Index Pigment Yellow 138 (C.I. PY138)

Footnote:

Eastaugh N, Chaplin T, Siddall R, Walsh V, “Pigment Compendium: A Dictionary and Optical Microscopy of Historic Pigments”, Routledge, Abingdon 2013

*Details of how each watercolour is tested are given in the May 2021 ARTicle “Testing and Assessing the Properties of Watercolours – Part 1 ” (see also Part 2 of the ARTicle, which was published in June 2021).