Automotive Paint Glossary

ABRASION RESISTANCE	Resistance to being worn away by rubbing or by friction; related more to toughness than to hardness. A necessary quality for automotive finish durability.
ABRASIVE	Used for wearing away a surface by rubbing. Examples are sandpaper, steel wool, compound, clay, scotch-brite, etc.
ACCELERATOR	A chemical that can be added to some paints to speed the curing time.
ACRYLIC	Synthetic resin used in a latex coating with good gloss and color retention.
ACRYLIC ENAMEL	Chemically enhanced enamel formulas are the mainstay of modern refinishing products. Many acrylic enamels recommend a catalyst, while others require it, to induce chemical reactions that produce a paint film of remarkable durability, chemical resistance, and gloss. Acrylic enamels can be polished like lacquer to a mirror finish.
ADHESION	The ability of a coating to stick to a surface.
AEROSOL	A product feature that uses compressed gas to spray the product from its container.
ALKALI	A substance such as lye, soda, or lime that can be highly destructive to paint films.
ALKYD	Synthetic resin modified with oil. Common in the early automotive enamels in the ‘60s, offered good adhesion to a clean surface, and good gloss, color retention, and flexibility, but tended to chalk out sooner and offer a shorter life that either the pervious lacquers, or the later acrylic enamels. Slow-drying.
ANTI-CORROSIVE PAINT	Metal paint designed to inhibit corrosion. Applied directly to metal.
BENZENE	Powerful but highly toxic and flammable solvent, usually restricted to spray application.
BENZINE	Often used as a lacquer dilutent. Highly volatile and a fire hazard in shipping and storing.
BINDER	Film-forming ingredient in paint that binds the pigment particles together.
BLEEDING	Undercoat staining through the top coat.
BLISTERING	The formation of bubbles or pimples on the painted surface caused by moisture or other contamination, by painting before the previous coat has dried thoroughly, or by excessive heat.
BLOCKING	Sanding primer or topcoats by hand with a flat backing surface such as a long-board or rubber sanding block.
BLUSHING	A gloss film turning flat or a clear lacquer turning white, usually caused by moisture
BUILD	Thickness or depth of paint film.
CATALYST	An ingredient that speeds up a chemical reaction; sometimes used in two-component paint systems. Sometimes referred to as activators, catalysts contain chemicals that interact with the resins of the base paint allowing it to cure more rapidly.
CHALKING	The formation of a loose powder on the surface of a paint after exposure to the elements.
CHECKING	A kind of paint failure in which many small cracks appear in the surface of the paint.
CLEAR COATING	A transparent protective and/or decorative film.
COHESION	Attraction of molecules within a coating [how it holds together).
COLORANT	Concentrated color that can be added to paints to make specific colors.
COVERAGE	The area over which a given amount of Paint will spread and hide the previous surface. (Usually expressed in square feet per gallon).
CRAZING	Small, interlacing cracks on surface of finish.
CURING	Final conversion or drying of a coating material.
DILUENT	Another term for solvents used to thin paint.
DRIER	A paint ingredient that aids the drying or hardening of the film.
DRY DUST FREE	That stage of drying when particles of dust that settle upon the surface do not stick to the paint film.
DRY TACK FREE	That stage of drying when the paint no longer feels sticky, or tacky when lightly touched.
DRY TO HANDLE	That stage of drying when a paint film has hardened sufficiently so the object or surface painted may be used without marring.
DRY TO RECOAT	That stage of drying when the next coat can be applied.
DRY TO SAND	That stage of drying when a paint film can be sanded without the sandpaper sticking or clogging
DURABILITY	The ability of paint to last or hold up well against destructive agents such as weather, sunlight, detergents, air pollution, abrasion, or marring.
ENAMEL	Broad classification Paints that dry to a hard finish. Enamel is a general term covering a wide range of paint, including hardware store spray cans. Single-stage alkyd automotive refinish enamels have been replaced by acrylic enamel which generally gives you the option of using a hardener or catalyst. Urethane enamels are even more durable and require a catalyst.
EPOXY	Clear finish having excellent adhesion qualities; extremely abrasion and chemical resistant. Epoxies are alcohol proof and very water resistant.
ETCH	Surface Preparation by chemical means to improve the adhesion of coatings.
ETCHING PRIMER	A primer with ingredients that etch into bare metal for better adhesion, also referred to as self-etching primer. Primarily used to prep bare metal.
FADING	The loss of color due to exposure to light, heat, or weathering.
FEATHER SANDING	Tapering the edge of dried paint film with sandpaper.
FILLER	Any material designed to fill surface flaws, from polyester body filler, spot putties and glazes, to primer surfacers.
FILM	Layer or coat of paint or other material applied to a surface.
FINISH COAT	Last coat of paint or other finish.
FISH-EYE	Small circular depressions nearly devoid of paint usually caused by surface contamination with oils or silicones
FLASH	The time required for the majority of the quick-evaporating solvents in the material being sprayed to evaporate or "flash" from the surface.
FLASH POINT	The temperature at which a coating or solvent will ignite.
FLAT	A painted surface that scatters or absorbs the light failing on it, so as to be substantially free from gloss or sheen.
FLEXIBILITY	Ability of a coating to expand and contract during temperature changes.
FLOATING	Separation of pigment colors on the surface of applied paint.
FLOWOUT	The desirable characteristic of droplets of sprayed material to meld together and level into a glass-smooth surface. Air pressure, gun atomization, and the amount of material being applied as well as the mixture of the paint all affect flow
GALVANIZED	A thin coating of zinc that covers iron or steel to prevent rust.
GLAZE	Material used to fill minor imperfections or improve the surface quality of body filler. Glazing putty was traditionally a single-component acrylic, although today catalyzed putties are available that reduce shrinkage. Fine grain and easy sanding are the main characteristics of glaze.
GLOSS	The luster or shininess of paints and coatings are generally classified as flat, semi-gloss, or gloss; the latter has the highest reflecting ability.
GLOSS METER	A standard scale for measuring the shininess light reflectance of paint.
HARDNESS	The ability of a paint film to resist denting, scratching, or marring.
HOLD-OUT	The ability of a paint film to dry to its normal finish on a somewhat absorptive surface.
HVLP	Stands for High-Volume, Low-Pressure; it refers to the design of modern spray equipment, initially introduced to meet air-quality regulations by reducing airborne overspray.
INHIBITOR	Material such as primer used to retard rusting or corrosion.
INTERCOAT ADHESION	The adhesion between two coats of paint.
INTERMEDIATE COAT	The coating between the primer and finish, often called a barrier coat.
LACQUER	The old standard for custom paint work, lacquers are a distinct paint type characterized by fast drying times and the ability to be polished to a beautiful luster. Poor durability and chemical resistance are the downside.
LAP	To lay or place one coat so its edge extends over and covers the edge of a previous coat, causing an increased film thickness.
LEVELING	Ability of a film to flow out free from ripples, pock- marks, and brush marks after application.
LIFTING	The softening and penetration of a previous film by solvents in the Paint being applied over it, resulting in raising and wrinkling.
LIGHTFASTNESS	No loss of color due to exposure to light, heat, or weathering.
MASKING	Temporary covering of areas not to be painted.
MASKING TAPE	A strip of paper or cloth similar to adhesive tape, which can be easily removed, used to temporarily cover areas that are not to be painted.
METALLICS	A class of paints that include metal flakes in their composition.
MINERAL SPIRITS	Paint thinners or solvents derived from petroleum.
Mixing Ratios	The amount of various components in the proper proportion to produce the final mix for spraying.
NONVOLATILE	The portion of a paint left after the solvent evaporates; sometimes called the solids content.
OPACITY	Ability of a paint to hide the previous surface or color.
OPAQUE COATING	A coating that hides the previous surface coating.
ORANGE PEEL	A surface flaw in which the paint goes on with too much texture. Usually caused by improper reducing or air pressure.
PAINT GAUGE	Instrument for measuring the thickness of paint film.
PAINT REMOVER	A compound that softens old Paint or varnish and permits scraping off the loosened material.
PEELING	Detachment of a dried paint film in relatively large pieces, usually caused by moisture or grease under the painted surface.
PIGMENTS	Paint ingredients mainly used to impart color and hiding power.
PIN HOLES	Small pin-sized holes in the paint, resulting from too much solvent, inadequate flash time, or surface contamination.
POLYURETHANE	Wide range of coatings, ranging from hard glossy enamels to soft flexible coatings. Good to very good adhesion, hardness, flexibility, and resistance. Surface preparation critical.
POT LIFE	Amount of time after mixing a two-part Paint system during which it can be applied.
PRIME COAT OR PRIMER	The first coat or undercoat that helps bind the top coat to the substrate.
PROPELLANT	The gas used to expel materials from aerosol containers.
REDUCER	A solvent used to thin (reduce) enamels, urethanes, and epoxies.
REMOVERS	Substances used to soften old paint so they may be removed easily.
RESIN	A natural or synthetic material that is the main ingredient of paint and that binds ingredients together. It also aids adhesion to the surface.
RUNS	Blemished film caused by excessive flow of coating.
RUST PREVENTIVE PAINT OR PRIMER	The first coat of paint applied directly to iron or steel structures to slow down or prevent rust.
SAGS	Excessive flow, causing runs or sagging in paint film during application. Usually caused by applying too heavy a coat of paint or thinning too much.
SEALER	A thin liquid applied to seal a surface, to prevent previous paint from bleeding through from the surface, or to prevent undue absorption of the topcoat into the substrate.
Sealing Primer	A primer used to isolate the existing substrate, or to provide some filling and surface enhancement under the final finish.
SEEDS	Small, undesirable particles or granules other than dust found in a paint.
SETTLING	Paint separation in which pigments and other solids accumulate at the bottom of the container.
SHRINKAGE	The characteristic of paint or filler to "shrink" with time as a full cure is reached, making surface flaws and sanding scratches reappear. Common with lacquer-based primers or acrylic spot putties.
SILICONE	See Resin.
Single-Stage	A paint system in which the color and gloss properties are both contained in a single topcoat product.
SKIN	Tough covering that forms on paints if container is not tightly sealed.
SOLIDS	See Nonvolatile.
SOLVENT	The volatile part of paint composition that evaporates during drying.
SPOT PRIMING	A method for protecting localized spots. The only areas primed are those that require additional protection due to rusting or peeling of the former coat.
SPRAYING	A method of application in which the coating material is broken up into a fine mist that is directed onto the surface to be coated.
STREAKING	The irregular occurrence of lines or streaks of various lengths and colors in an applied film; usually caused by some form of contamination.
STRIP	Removal of old finishes with paint removers.
STYRENE-BUTADIENE	See Resin.
SUBSTRATE	Surface to be painted.
SURFACING PRIMER or PRIMER/SURFACER	A primer designed specifically to build thickness for filling shallow surface flaws by sanding.
TACK RAG	A piece of loosely woven cloth that has been dipped into a varnish oil and wrung out. When it becomes tacky of sticky, it is used to wipe a surface to remove small particles of dust.
TACKY	Sticky condition of coating during drying, between wet and dry-to-touch stage.
TEXTURE	The roughness or irregularity of a surface.
THINNER	Solvent used to thin lacquer-based products – similar to REDUCERS used in enamels & urethanes.
TOUCH UP	The ability of a coating film to be spot repaired (usually within a few months of initial painting) without showing color or gloss differences.
TWO STAGE	A paint system in which the color is applied as a primary product (basecoat) followed by a clearcoat to provide gloss and reflectivity.
UNDERCOAT	A primer or intermediate coating applied before the finish coating.
URETHANE	Similar to acrylic enamels, but using urethane resins. Urethane has most of the desirable features of acrylic enamel but with enhanced durability, although they generally dry slower.
VEHICLE	The liquid portion of a paint composed mainly of solvents, resins, or oils.
VISCOSITY	The thickness of a coating as related to its ability to flow as a liquid.
VOC	Volatile organic chemicals; the VOC level of the final sprayable mix of the various paint and undercoat products is highly regulated in some regions.
WATER SPOTTING	A Paint appearance defect caused by water droplets.
WEATHERING	The effect of exposure to weather on paint films.
WET EDGE	Length of time paint can stand before applying additional material without showing a lap.
WET-SANDING	Sanding with wet-type sandpaper with water to clean away the sanding debris. Creates a higher-quality surface than dry sanding and makes the paper last longer without clogging up.
WRINKLING	Development of ridges and furrows in a paint film when the paint dries.
YELLOWING	Development of a yellow color or cast in white, pastels, colored, or clear finishes.
ZINC CHROMATE	Rust-inhibiting Pigment, greenish-yellow in color, that are used with a high-hiding pigment.