A colourant usually is an organic substance that reflects colour and can bind (to a certain degree) to the material it is applied on. Colourants dissolve easily in water or in oil.
A pigment is an organic or inorganic substance that reflects colour. Pigments don’t bind (easily) to a material and aren’t soluble, but are used as dispersion.
Ink is a fluid or paste used to add colour to materials. There are multiple definitions of ink: some only consider a solution of colourants ink, others say it can consist of pigments as well.
Dye is a substance used to create a reflective layer on a carrier. It consists of three parts: pigments or powdered colourants, a binder that hardens when it dries and a thinner of the binder that evaporates.
Painting plants can be used in the following printing techniques:
Screen printing, a printing technique whereby a mesh is used to transfer ink onto a substrate, except in areas made impermeable to the ink by a blocking stencil.
Lithography, whereby the ink is applied on elevated parts of a woodcut or a linocut.
For the intaglio technique (etching) and planography (lithography)
good functioning binders haven’t been found yet. With exception of photopolymeer printing – a graphic technique whereby a light-sensitive plastic is turned into a printing plate using UV-light.
NADES is the abbreviation of NAtural Deep Eutectic Solvents. These are natural solvents in which colourants possibly solve well. NADES are created from a combination of two or more organic substances, which individually are solid (at room temperature), but fluid when mixed together.
Edible painting plants are plants that can both be used for creating dyes and food.
Examples are saffron, walnut, red beet and nettle.
Mordants are agents to improve adhesion and photostability of dyestuffs. Most mordants consist of heavy metals. With the painting plants project we are looking for natural mordants; mordants of a natural origin.
The photostability of a dye is a measurement of how long the dye keeps its colour when exposed to (sun)light.