Natural hair brushes are superior to synthetic hair brushes for liquid holding capacity, the hollows and indentations found on the surface of the cuticle of the hairs pick up water and pigment really well, which is why natural hair is considered the best for liquid holding capacity – once the brush is pressed against the paper being painted on, all the liquid and pigment is deposited on to the surface. Soft fine hair is particularly favoured for wash applications as it has less of a ‘snap’, and will create gentle fluid marks with no crisp edges.
I also use synthetic brushes for precision, spring and detail. Synthetic hair does not have the scale-like cuticle layer that natural hair possesses, so does not hold liquid as well, however synthetic hair brushes possess a greater spring, they are more resilient and if looked after, have a much greater lifespan. These characteristics make them suitable for watercolour painting techniques that demand greater control, and crisper, finer detailed work. I use Toray hair brushes which is a very fine nylon hair which is perfect for the fine detailed style of my Pet Portraits.