Density:-
Mass per unit volume; expressed as gm/cm3, Kg/dm3 at a stated temperature. See Relative density

Diluent:-
A volatile liquid which, while not a solvent for a particular binder, may be added to the true solvent without causing precipitation. Also the liquid phase of a binder dispersion.

Dirt Pick-Up:-
The tendency of a film of a coating material to attract soiling material that cannot be removed by simple washing.

Dirt Retention:-
A defect characterised by the tendency of the dry film of a coating material to retain soiling material.

Dirt Resistance:-
The property of a film of a coating material to resist soiling, other than that from micro-organisms, which is deposited or embedded in the dried film.

Dry spray:-
Poor gloss, powdery surface. Caused by Poorly mixed paint. Thinners evaporating too fast. Excessive air pressure causes fine sprays which dries to a dust in the air and settles.

Dry Film Thickness (DFT):-
Paint essentially consists of 3 components. Pigment, Binder and solvent. The solvent being present to allow viscosity adjustment for correct application the pigment and binder form the real surface coating.During and after application the solvent evaporates and thereafter takes no further part in the process. As the dry component is the true paint its durability and functionality can be dictated by the thickness of this film which, when measured, is termed the "Dry Film Thickness". Control of wet film thickness during application is essential to ensure the correct dry film. Control of the wet film thickness during application also ensures that excessive paint is not used and so ensuring optimum & cost effective results. See WFT.

Dye:-
A colourant that is generally organic in nature and soluble in the relevant solvent or media; it will absorb certain wavelengths of visible light and transmit the balance, but does not scatter light; is transparent.