Emulsion paint consists of tiny polymer particles within which the pigments are trapped. The particles are suspended in water, then as the paint dries the particles fuse together creating a film of paint on the wall. Once this happens the polymer can’t be resuspended in water, which is why you can’t wash a water-based emulsion paint back off the wall once it has dried.

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But how does it break down?

Pigments - 25 per cent

Titanium dioxide is used for white, iron oxide for yellows, reds and browns, chromium oxide for greens, and carbon is used for blacks.

Solvent - 45 per cent

Nearly half of emulsion paint is made up of water.

Binders - 25 per cent

Acrylic or epoxy polymers surround the pigments and help them to bind to the wall.

Other additives - 5 per cent

These include biocides to stop algae and fungi growing on your walls.

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