The following glossary contains terms used commonly in the paint and coatings industry to describe the characteristics, usage and components of paints and coatings.
Involves either removal of the painted surface, covering the painted surface with an impermeable surface, or covering surface with heavy-duty coating (encapsulant).
A synthetic resin used in high-performance water-based coatings. A coating in which the binder contains acrylic resins.
The ability of dry paint to attach to and remain fixed on the surface without blistering, flaking, cracking or being removed by tape.
A product that uses compressed gas to spray the coating from its container.
One method by which liquid coatings cure to a dry film. Oxygen from the air enters the film and cross-links the resin molecules. Also called “Air Dry” and “Oxidizing.”
Synthetic resin modified with oil. Coating that contains alkyd resins in the binder.
A functional group which can act as an epoxy resin curing agent.
Paints formulated especially for boat decks and hulls, docks and other below-water-line surfaces and structures to prevent the growth of barnacles and other organisms on ships’ bottoms.
Solid ingredients in a coating that hold the pigment particles in suspension and attach them to the substrate. Consists of resins (e.g., oils, alkyd, latex). The nature and amount of binder determine many of the paint’s performance properties— wash ability, toughness, adhesion, colour retention, etc.
Formation of dome-shaped projections in paints or varnish films resulting from local loss of adhesion and lifting of the film from the underlying surface.
The thickness or viscosity of a fluid.
Linseed (sometimes soya) oil that was formerly heated for faster drying. Today, chemical agents are added to speed up the drying process.
A gas which is chemically combined with styrene to create a resin used in latex binders, styrene-butadiene.
Substance whose presence increases the rate of a chemical reaction, e.g., acid catalyst added to an epoxy resin system to accelerate drying time.
Formation of a powder on the surface of a paint film caused by disintegration of the binder during weathering. Can be affected by the choice of pigment or binder.
A measurement of colour. The degree of saturation of a hue. A colour at its full intensity has maximum chroma.
A transparent protective and/or decorative film; generally the final coat of sealer applied to automotive finishes.
The small amount of solvent contained in latex coatings. Not a true solvent since it does not actually dissolve the latex resins, the coalescent aid helps the latex resins flow together, aiding in film formation.
A paint, varnish, lacquer or other finish used to create a protective and/or decorative layer. Generally used to refer to paints and coatings applied in an industrial setting as part of the original equipment manufacturer’s (OEM) process.
A bonding together of a single substance to itself. Internal adhesion.
Concentrated colour (dyes or pigments) that can be added to paints to make specific colours
Non-fading in prolonged exposure to light.
The ability of paint to keep its original colour. Major threats to colour retention are exposure to ultraviolet radiation and abrasion by weather or repeated cleaning.
A type of metal paint or primer that prevents rust by preventing moisture from reaching the metal. Zinc phosphate, barium metaborate and strontium chromate (all pigments) are common ingredients in corrosion-inhibitive coatings. These pigments absorb any moisture that enters the paint film.
A liquid coating made from coal tar once used as a wood preservative. It has been banned for consumer use because of potential health risks.
The process whereby a liquid coating becomes a hard film. Dead Flat: No gloss or sheen.
A liquid used in coatings to reduce the consistency and make a coating flow more easily. The water in latex coatings is a diluent. A diluent may also be called a “Reducer,” “Thinner,” “Reducing Agent” or “Reducing Solvent.”
Various compounds added to coatings to speed the drying.
Powder-type colours to be mixed with water, alcohol or mineral spirits and resin to form a paint or stain.
An oil that when exposed to air will dry to a solid through chemical reaction with air: linseed oil, tung oil, perilla, fish oil, soybean oil.
Those pigments that are obtained from the earth, including barytes, ochre, chalk and graphite.
Gloss lying between semi gloss and flat. Emulsion: A mixture of solids suspended in a liquid.
Coating in which resins are suspended in water, then flow together with the aid of an emulsifier. Example: latex paint.
Broad classification of paints that dry to a hard, usually glossy finish. Most equipment-coating enamels require baking. Enamels for walls do not.
Extremely tough and durable synthetic resin used in some coatings. Epoxy coatings are extremely tough, durable and highly resistant to chemicals, abrasion, moisture and alcohol.
Ingredients added to paint to increase coverage, reduce cost, achieve durability, alter appearance, control rheology and influence other desirable properties. Less expensive than prime hiding pigments such as titanium dioxide. Examples: barium sulphate, calcium carbonate, clay, gypsum, silica, talc. May also improve coating performance.
Amount of thickness produced in an application. Millimetres (mils) of dry film per mils of applied wet film.
Depth or thickness of the dry coating in millimetres.
The ability of a coating to withstand fire or to protect the substrate to which it is applied from fire damage.
A coating which will (1) reduce flame spread, (2) resist ignition when exposed to high temperature or (3) insulate the substrate and delay damage to the substrate.
A surface that scatters or absorbs the light falling on it so as to be substantially free from gloss or sheen (0-15 gloss on a 60-degree gloss meter).
Baking the paint between room temperature and 150_ F to speed the drying process.
Process in which a thin coating of zinc is applied to iron or steel to prevent rust.
The lustre or shininess of paints and coatings. Different types of gloss are frequently arbitrarily differentiated, such as sheen, distinctness-of-image gloss, etc. Trade practice recognizes the following gloss levels, in increasing order of gloss: flat (or matte)– practically free from sheen, even when viewed from oblique angles (usually less than 15 on 60-degree meter); eggshell—usually 20-35 on 60-degree meter; semi-gloss—usually 35-70 on 60- degree meter; full-gloss—smooth and almost mirror-like surface when viewed from all angles, usually above 70 on 60-degree meter.
A device for measuring the light reflectance of coatings. Different brands with the same description (such as semi gloss or flat) may have quite different ratings on the gloss meter.
Curing agent for epoxies or fibreglass.
Pollutants that are known or suspected to cause cancer or other serious health effects, such as reproductive effects or birth defects, or adverse environmental effects.
High-efficiency particulate air-filtered vacuum designed to remove lead- contaminated dust.
A material that will not react chemically with other ingredients.
A series of steps used as an alternative to lead-based paint removal. Improves condition of intact lead based paint to reduce and/or eliminate hazards without total removal.
A mechanism whereby fire-retardant paints protect the substrates to which they are applied. An intumescent paint puffs up when exposed to high temperatures, forming an insulating, protective layer over the substrate.
A fast-drying usually clear coating that is highly flammable and dries by solvent evaporation only. Can be reconstituted after drying by adding solvent.
General term used for water-based emulsion paints made with synthetic binders such as 100% acrylic, vinyl acrylic, terpolymer or styrene acrylic. A stable emulsion of polymers and pigment in water.
A metal, used as a pigment in paints.
Drying oil made from the flax seed. Used as a solvent in many oil- based paints. “Boiled” linseed oil can be used to protect wood from water damage. Sometimes used as a furniture polish.
Solution of soluble driers in organic solvents. Lithopone: A white pigment of barium sulphate and zinc sulphide.
Lithopone was once a primary substitute for lead carbonate or “white lead” pigments; it has been largely replaced by titanium dioxide.
Coating specially designed for immersion in water and exposure to marine atmosphere. (See also Anti-fouling Paint)
Information sheet that lists any hazardous substance that comprises one percent or more of the product’s total volume. Also lists procedures to follow in the event of fire, explosion, leak or exposure to hazardous substance by inhalation, ingestion or contact with skin or eyes. Coatings manufacturers are required to provide retailers with an MSDS for every product they sell to the retailer. Sales clerks should make MSDS’s available to retail customers.
Paint thinner. Solvent distilled from petroleum.
Substance composed of low molecular weight molecules capable of reacting with like or unlike molecules to form a polymer.
A petroleum distillate used mostly by professionals (as opposed to do-it- yourself painters) for cleanup and to thin solvent-based coatings. A volatile organic compound (see VOC).
Resins from trees, plants, fish and insects. Examples: damars, copal’s. Non-volatile: The portion of a coating left after the solvent evaporates; sometimes called the solids content.
A paint that contains drying oil, oil varnish or oil-modified resin as the film-forming ingredient. The term is commonly and incorrectly used to refer to any paint soluble by organic solvents.
A natural plant product that contains oil and resins. Turpentine is an example.
Chemical reaction upon exposure to oxygen. Some coatings cure by oxidation, when oxygen enters the liquid coating and cross-links the resin molecules. This film-forming method is also called “Air Cure” and “Air Dry.” (Oxidation also causes rust on bare metals.)
A coating including resin, a solvent, additives, pigments and, in some products, a diluent. Paints are generally opaque, and commonly represent the portion of the industry known as “architectural coatings.”
A chemical that softens old paint or varnish and permits it to be easily scraped off. Also called “stripper.”
A finish that sinks into the substrate, as opposed to settling on the surface.
Insoluble, finely ground materials that give paint its properties of colour and hide. Titanium dioxide is the most important pigment used to provide hiding in paint. Other pigments include anatase titanium, barium metaborate, barium sulphate, burnt sienna, burnt umber, carbon black, China clay, chromium oxide, iron oxide, lead carbonate, strontium chromate, Tuscan red, zinc oxide, zinc phosphate and zinc sulphide.
Substance, the molecules of which consist of one or more structural units repeated any number of times; vinyl resins are examples of true polymers.
The interlocking of molecules by chemical reaction to produce very large molecules. The process of making plastics and plastic-based resins.
A synthetic resin used in the binders of coatings. Tends to discolour under exposure to ultraviolet radiation. Commonly called “vinyl.”
First complete coat of paint of a painting system applied to a surface. Such paints are designed to provide adequate adhesion to new surfaces or are formulated to meet the special requirements of the surfaces.
The gas used to expel materials from aerosol containers.
Synthetic or natural material used as the binder in coatings. Can be translucent or transparent, solid or semi-solid. Examples: acrylic, alkyd, copal ester, epoxy, polyurethane, polyvinyl chloride, silicone.
Natural resin obtained from living pine trees or from dead tree stumps and knots. Semi-gloss Finish: Finish that has a low lustre sheen. Semi-gloss paints are formulated to give this result (usually 35-70 degrees on a 60-degree meter).
A coating made from purified lac dissolved in alcohol, often bleached white.
A resin used in the binders of coatings. Also used as an additive to provide specific properties, e.g., defoamer.Paints containing silicone are very slick and resist dirt, graffiti and bacterial growth, and are stable in high heat.
The part of the coating that remains on a surface after the vehicle has evaporated. The dried paint film. Also called Non-volatile.
Any liquid which can dissolve a resin. Generally refers to the liquid portion of paints and coatings that evaporates as the coating dries.
Steps taken to reduce waste generation and toxicity at the source through more effective utilization of raw materials and reformulation.
Mirror-like finish (usually 60 degrees on a 60-degree meter). Substrate: Any surface to which a coating is applied.
White pigment in virtually all white paints. Prime hiding pigment in most paints.
Distilled pine oil, used as a cleaner, solvent or thinner for oil-based and alkyd coatings.
An important resin in the coatings industry. A true urethane coating is a two- component product that cures when an isocyanate (the catalyst) prompts a chemical reaction that unites the components.
Portion of a coating that includes all liquids and the binder. The vehicle and the pigment are the two basic components of paint.
The property of a fluid whereby it tends to resist relative motion within itself.
The defining quality of a liquid that evaporates quickly when exposed to air.
Organic chemicals and petrochemicals that emit vapours while evaporating. In paints, VOC generally refers to the solvent portion of the paint which, when it evaporates, results in the formation of paint film on the substrate to which it was applied.
Solid ingredients as a percentage of total ingredients. The volume of pigment plus binder divided by the total volume, expressed as a percent. High-volume solids mean a thicker dry film with improved durability.
Coatings in which the majority of the liquid content is water. White Lead: Lead carbonate