Paints and pigments

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-Phosphorescent= Glow in the dark, able to absorb light energy and store it, the stored energy is released as light over-time (helps us know where things are in the dark)

-Thermochromic= are sensitive to temperature, change colour depending on heat (helps tell you when something is too hot or too cold

Pigments give paint its colour

Binding medium is a liquid that carries the pigment bits and holds them together, when the binding medium goes solid it sticks the pigments to the surface you've painted

The solvent is the stuff that thins the paint and makes it easier to spread

Paints are colloids

a colloid consists of really tiny particles of one kind of stuff dispersed with another (they are not dissolved)

they can be (particles) bits of solid, droplets of water and bubbles of gas

they don't separate because the particles are so small

There are two types of pigments

Paint can be water based or oil based, paint dries as solvent evaporates

- Emulsion paints are water based, the solvent used in these paints is water + the binding medium is usually and acrylic/vinyl acetate polymer

- they are fast drying and don't produce harmful fumes

- Gloss/oil paints are oil based, the binding material is oil and the solvent is an organic compound that will dissolve in oil

-Dries in 2 stages 1. solvent evaporates 2. oil is oxidised by oxygen in air before turning solid

- they are glossy, waterproof and hard wearing but produce harmful fumes

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