Properties and characteristics :
Colour absorption capacity ; the more the hair or bristle is tapered and the more its "belly" is accentuated, the better its capillary retention and the more regular the colour distribution. Natural hairs and bristles have scales that ensure this function (see photos 1, 2 and 3 taken with an electronic microscope), vital for liquid or semi-paste techniques. Synthetic fibres, which do not have scales (see photo 4) allow the colour to flow off.
Retention or reserve :
The properties inherent in each fibre or by their length ; tracers, letter brushes.
Elasticity, responsiveness, springiness :
Depends on the nature of the fibre and its trim length - the visible length of the fibre - and the width/thickness pairing ; the shorter and/or thicker the fibre, the better its shape memory. The longer the fibre, the more flexible the brush.
See photos 5 and 6 :
When immersed in water, squirrel hair visibly swells with water and almost doubles in volume. Sable dilates significantly whereas synthetic fibre does not change. This experiment is aimed at demonstrating the retention power of a paintbrush depending on the type of hair or bristle selected.
Copyright © Raphaël 2012