An A to Z of painting terms

Intercoat Adhesion
The adhesion between successive coats of paint.

Intercoat Contamination
The presence of foreign matter such as dust or dirt between successive coats of paint.

Lacquer
A coating comprised of a synthetic film forming material which is dissolved in organic solvents and dries by solvent
evaporation.

Latex
A stable dispersion of a polymer substance in an aqueous medium; a common term for water reducible coatings.

Lead-Free
Contains, by weight, less than 0.5% lead for industrial products and less than 0.6% lead in consumer products.

Leafing
The orientation of pigment flakes in a horizontal plane, usually aluminum.

Lifting
Softening and raising or wrinkling of a previous coat by the application of an additional coat; often caused by
coatings containing strong solvents.

Mastic
A term used to describe a heavy bodied coating.

Micron
A micrometer or one millionth of a metre.

MIL
One one-thousandth of an inch; 0.0001 inches. Commonly used to denote coating thickness.

Mist Coat
A thin tack coat usually applied to fill porous surfaces such as plaster.

Mottled
Spots of different tones and colors next to each other resulting in a blotchy effect on the coating film.

Non-Drying Oil
An oil which undergoes little or no oxidation when exposed to air and therefore has no film forming
properties.

Opacity
The ability of a paint film to obliterate or hide the color of the surface to which it is applied.

Overspray
Sprayed coating that is dry when it hits the surface resulting in dusty, granular adhering particles, reducing gloss and presenting a poor appearance.

Oxidation
The formation of an oxide; the curing mechanisms for alkyds.

Paint
(Verb) To apply a thin layer of coating to a substrate by brush, roller, spray or other suitable method.
(Noun) A pigmented liquid designed for application to a substrate, in a thin layer, which is then converted to an solid film. Paint is designed to protect and/or decorate the surface it is applied to.

pH
A measure of acidity and alkalinity; pH 1-7 is acid and pH 7-14 is alkali.

Pigment
A finely ground natural or synthetic, insoluble particle adding color and opacity or corrosion inhibition to a coating
film.

Pigment / Binder Ratio
A ratio of total pigment to binder solids in paint.

Pinholing
A film defect characterized by small, pore-like flaws in a coating which extend entirely through the film.

Plasticiser
An agent added to the resin to aid in flexibility.

Polyester Resin
A group of synthetic resins which contain repeating ester groups. A special type of modified alkyd resin.

Pot Life
The length of time a paint material is useful after its original package is opened or a catalyst or other curing agent is
added.

Primer
The first coat of paint applied to a surface, formulated to have good bonding, wetting and inhibiting properties.

QUV
An accelerated testing device designed to evaluate the fading properties of a coating by exposure to high intensity,
ultraviolet light.

Reducer
Commonly known as thinner.

Reflectance
The ratio of the intensity of reflected light to that of incidental light.

Resin
A group of organic materials, either natural or synthetic, which can be molded or dissolved.

Roller
A cylinder covered with lamb's wool, felt, foamed plastics or other materials used for applying paint.

Runs
Sagging and curtaining of a coating or paint film, usually caused by improper thinning, excessive film build or poor
application techniques.

Sag Resistance
The ability of a paint to be applied at proper film thickness' without sagging.

Sagging
The downward movement of a paint film on a vertical surface, between the time of application and drying, resulting in an uneven coating having a thick lower edge.

Sealer
A coating used on absorbent surfaces prior to painting.

Settling
The sinking of pigments, extenders or other solid matter in a paint, on standing in a container, with a consequent
accumulation on the bottom of the can.

Shade
A term employed to describe a particular hue or tone.

Shelf Life
The maximum time interval in which a material may be kept in a usable condition during storage.

Skinning
The formation of a solid membrane on the of a liquid, caused by partial curing or drying of the coating during
storage.

Solvent
A liquid in which another substance may be dissolved.

Specification
A set of instructions detailing the plan for coating of a project; a list of criteria for a coating.

Substrate
The surface to be painted.

Thinners
A liquid (solvent) added to a coating to adjust viscosity.

Two-Pack
A coating which is supplied in two parts and must be mixed in the correct portions before use in order to cure.

Undercoat
The coat applied to the surface after preparation and before the application of a finish coat.

Viscosity
A measure of fluidity of a liquid.

Water Spotting
A surface defect caused by water droplets depositing a circular ring of contaminants.

Zinc Dust
Finely divided zinc metal used as a pigment in protective coatings.