Glossary of Terms

Unsure about a technical term, looking for a solution for a common finishing problem or easy-to-follow instructions on techniques? Our troubleshooting guide is here for you!

Glossary of Terms

Unsure about a technical term, looking for a solution for a common finishing problem or easy-to-follow instructions on techniques? Our troubleshooting guide is here for you!
Search for glossary terms (regular expression allowed)
Term Main definition
A
A
Acetone

A volatile solvent, excellent in mixtures (such as mixing with oil and water).

Acrylics

Resins resulting from the polymerization of esters of acrylic and methacrylic acids. Most acrylics require strong solvents, although some may be formulated using aromatic hydrocarbons without oxygenated solvents.

Additive

Any chemical added in small amounts to a coating to achieve specific properties (mar resistance, slip, etc.)

Air Dry Coating

A coating formulation that dries after application without the use of heat.

Air-Assisted Airless

A compromise between conventional spray and airless spray methods, air-assisted spray technology uses a small amount of atomizing air with higher fluid pressures to allow for good film appearance with good transfer efficiency.

Alcohol

Latent solvents for many materials. Characterized by the presence of a hydroxyl group. Capable of strong hydrogen bonding. Oxygenated solvents.

Alkyd / Urea

Blend of resins most commonly used in conversion coatings. Releases characteristic formaldehyde odor.

Alkyd Paint

Paint made with synthetic resins which have good retention of color and flexibility. Also oil-modified alkyd which contains a drying oil as part of its makeup.

Alkyds

Synthetic resins formed by the condensation of polyhydric alcohols and polybasic acids. They may be regarded as complex esters. Most commonly made from glycerin and phthalic anhydride. Solvent requirements vary, ranging from strong aromatic hydrocarbons to low solvency aliphatic hydrocarbons.

Architectural Coating

Coatings intended for on-site application to interior or exterior surfaces of residential, commercial, institutional, or industrial buildings. These finishes are applied at ambient temperatures and dry without being heated. Also called trade sales coatings.

Aromatics

Characterized by unsaturated, six carbon benzene ring structures. Hydrocarbon solvents which contain more than 50% aromatic compounds are designated as aromatic hydrocarbon solvents. Strongest of the hydrocarbon solvents. Strongest odor.

Auto Ignition Point

Temperature at which vapor from volatile material self-combusts.

B
B
Baking Finish

A coating which requires heat for curing and the development of desired properties.

Base Solvent

The solvent blend which is used in the preparation of a coating for dissolving the resin and dispersing the pigments.

Bénard Cells

Small, rounded variations in the surface color in opaque films caused by eddies and currents created from the evaporation of solvents.

Binder / Backbone

The name given to the blend of resins in a coating which gives a film most of its properties.

Blister

Film defect which occurs when volatiles leaving a film are trapped and expand inside the film.

Bloom

A clouding of the finish material coming in contact with dirt or moisture.

Blush

A milky appearance in a film created when airborne moisture condenses in a film cooled by evaporating solvents.

Brilliance

The percentage of incident light reflected by an object. A perfectly white material has 100% brilliance while an absolute black material has zero brilliance.

Build

The apparent depth a coating gives to its substrate.

Butyrate

UV-resistant resin with characteristics of a lacquer. Used where light stability and good flow are needed.

C
C
Catalyst

The highly reactive chemical which when added to conversion coatings initiates chemical bonding.

Chromatic Scale

Color

Approximate wave length: (Millimicrons)

Color Classification

Obtained by mixing

Red

610 to 700

Primary

---

Yellow

570 to 590

Primary

---

Blue

460 to 500

Primary

---

Orange

590 to 610

Secondary

Red and Yellow

Green

500 to 570

Secondary

Yellow and Blue

Violet

400 to 460

Secondary

Blue and Red

Citron

---

Tertiary

Orange and Green

Olive

---

Tertiary

Green and Violet

Russet

---

Tertiary

Violet and Orange

Coating

A generic term for paints, lacquers, enamels, etc. Also a liquid composition which is converted to a solid protective, decorative, or functional adherent film after application as a thin layer.

Cold Check

The cracks formed from the expansion and contraction which results from hot and cold cycles.

Color

The quality by which bodies have a different appearance, independently of their form, depending on the effect of different wavelengths on the retina of the eye.

Color Float

The tendency for certain pigments in a coating to rise to the surface in unagitated material.

Colorimeter

A computerized meter which digitally “fingerprints” a specific opaque color according to its characteristic wavelengths of light.

Complementary colors

Red and green, blue and orange, yellow and violet are complementary pairs of colors. Complementary colors from a given pair are always harmonious when used near each other as separate colors in the proper relative amounts.

Conventional Spray

A traditional spray finishing method that gives excellent atomization of the paint at the expense of lower transfer efficiency.

Conversion

The process of chemically bonding or crosslinking the resins in a film.

Cosolvent

A blend of two or more solvents, none of which will dissolve the resin by itself, but which will act as a true solvent for the material when used together. Each cosolvent must evaporate at about the same rate, otherwise resin precipitation will occur as drying proceeds.

Coverage

Mileage, usually given in square feet per gallon for a given dry film thickness.

Crater

The “pulling away” from surface contamination which forms a crater-like deformation in the film.

Crazing

Term often used in place of cold checking.

Crosslink

The chemical bonding of resins (polymers).

Crystalline Wax

A blend of highly refined micro-crystalline fossil-origin waxes used to revive and protect valuable furniture, leather, paintings, metals, marble, onyx, ivory, etc. Freshens colors and imparts a soft sheen.

D
D
Diluent

Materials used to thin paints, either to make them more workable or to give them a consistency which is suited to a particular technique. In theory a diluent is only a temporary addition to paint and should evaporate evenly and completely during drying, leaving the original composition of the paint unchanged, and producing no lasting odor or stain.

Dispersion

The wetting-out of fine pigment particles with coating material.

Distillation Range

The temperature range over which a mixture of liquids will distill. The range is narrow for most oxygenated solvents, but may be quite wide for hydrocarbons. ASTM Method D-86 is used for hydrocarbons.

Distinctness of Image (DOI)

The degree of distortion in a reflected image on the surface of a high gloss coating.

E
E
Enamel

A topcoat which is characterized by its ability to form a smooth surface. May also refer to a thermosetting or baking finish.

Epoxy Resin

Resins which contain epoxy groups (also known as oxirane groups). Most commonly made from epichlorohydrin and bisphenol A. May be liquid or solid, depending on molecular weight. Uses mixtures of alcohols, ketones and hydrocarbons.

Ester

A class of active solvents formed from organic acids and alcohols by the elimination of water. Oxygenated solvents.

Ethanol (or ethyl alcohol)

A volatile solvent widely used in industry but of relatively minor importance to artists. It is the solvent for shellac and a few other resins, a diluent for some of the fixatives, and a mildly active wetting agent.

Evaporation Profile

The relationship of evaporation out of a film as a function of time produced by a blend of solvents in a coating.

Evaporation Rate

A measure of the length of time required for a given amount of a solvent to evaporate. Solvents are generally characterized as fast, medium or slow evaporating. Most commonly measured using the Shell Thin-Film Evapometer, ASTM Method D-3539.

F
F
Filler

Highly pigmented material used to fill the open pores of wood before the application of a coating.

Fisheye

A type of crater but is usually larger and sometimes contains a particle of contamination.

Flash Off

The initial evaporation of solvent from an applied film.

Flashpoint

The temperature at which a vapor from a volatile material will combust if externally ignited.

Flexibility

The elasticity a coating needs to overcome physical deformation.

Flow

The ability of a material to level-out over surface defects.

Fractional Polarity

A measure of the polar character of a solvent. Values are between zero and one, the higher the value, the more polar the solvent. Hydrocarbons have very low polarity, while oxygenated solvents have higher polarity.

G
G
Gesso

A white fluid or plastic coating material made by mixing chalk or whiting with a glue solution or, occasionally, casein. Early gesso was made from parchment glue and slaked plaster of Paris~ modern gesso uses rabbitskin glue and precipitated chalk or whiting. The word gesso is Italian, and derives from gypsum, from which plaster of Paris is made. However manufacturers in recent years have applied the term to polymer primers, which are entirely different from gesso in composition and cannot be used as a substitute for it.

Gilding

To cover with gold or a golden finish, whether by applying gold leaf, by electroplating or metal spraying or applying gold paint.

Gloss

The degree to which a coating is able to reflect an image.

Glycol Ethers

Prepared from alcohols and ethylene or propylene oxide. Contain both ether groups and hydroxyl groups, thereby possessing the characteristics of both. Oxygenated solvents.

H
H
House Paint

A coating designed for use on large exterior surfaces of a building. Generally of lower gloss than the coating used on trim areas. May be either water based or oil based.

Hue

The predominate wavelength reflected by a colored material which determines its position in the chromatic scale.

HVLP

A finishing spray method that uses a high volume of air at a low pressure to atomize paint into a pattern of low speed particles, thus producing better transfer efficiency than conventional air.

Hydrocarbons

Compounds composed exclusively of hydrogen and carbon.

I
I
Intercoat Adhesion

The adhesion a topcoat has to a previous coat.

J
J
Jetness

Refers to how deep a black coating looks when compared to other black coatings.

K
K
Ketone Resin

These resins are added to all types of coatings formulations to improve properties such as gloss, film hardness, flow and UV stability. In addition, thanks to their excellent pigment-wetting properties and broad compatibility with other resins, they can be used to make all-purpose pigment preparations.

Ketones

A class of active, strong solvents characterized by a carbonyl group. Oxygenated solvents.

L
L
Lacquer

A coating based on a thermoplastic polymer dissolved in organic solvent and which dries primarily by solvent evaporation. The coating can be redissolved in its’ original solvent blend. The most common polymers used in lacquers are nitrocellulose, vinyl resins and acrylic resins.

Latent Solvent

A solvent which is not a true solvent for the material being dissolved, but which will act as a solvent in the presence of an active solvent. Alcohols are the most common latent solvents.

Latex

A stable dispersion of a polymer in a continuous liquid medium, usually water. Prepared by emulsion polymerization.

Latex Paint

A coating which uses a latex as the principal binder. Widely used for interior and exterior house paints. Contains only small amounts of solvents, usually glycols, glycol ethers and glycol ether esters.

Lifting

The wrinkle or seedy look which occurs from the stripping effect a topcoat with active solvents has on a cured bottomcoat.

M
M
Mar Resistance

Ability of the dry film to resist scratching.

Masstone

A full strength color. The hue of a color not toned with white or black.

MEK Rubs

A way of determining solvent resistance and extent of cure by rubbing the surface of a coating with a cloth laden with methyl ethyl ketone.

Metamerism

The characteristic of a color which enables it to appear differently under various types of lighting.

Mil

1/1,000th of an inch.

Mileage

The number of pieces or the square feet which are able to be coated by 1 gallon of material at a specific coating depth in mils.

Monomer

A small reactive molecule which chemically bonds to form a polymer.

N
N
Naphthenes

Completely saturated hydrocarbons characterized by ring structures. Intermediate solvency between paraffin and aromatic hydrocarbons. Intermediate odor. Also known as cycloparaffins.

NGR Stain

A non-grain raising stain used to give uniformity and transparency to the color of a substrate.

Nitrocellulose

A resin used in lacquers for clarity, quickness of dry and repairability.

Nonaqueous Dispersion (NAD)

The solvent analog of a latex: a dispersion of a polymer in a volatile organic liquid which is not a solvent for the polymer. Low-solvency aliphatic hydrocarbons are the most commonly used solvents.

O
O
Oil Paint

Paint that contains a drying oil as the sole film-forming ingredient. Linseed oil is most commonly used for this purpose. Aliphatic hydrocarbons are used in small amounts as the solvent.

Oil Varnish

A solution of oxidizing resin dissolved in hydrocarbon solvent.

Orange Peel

The slight “bumpy” appearance a sprayed surface has when the coating does not have enough flow.

Organic

The term that refers to any compound that contains carbon atoms.

Overspray

The atomized spray material which misses the desired substrate and lands on an undesirable area.

Oxygenated Solvent

General designation of those solvents which contain oxygen in addition to carbon and hydrogen.

P
P
Pad Stain

The stain applied to blend in off-color regions of wood.

Paint

Any pigmented liquid designed for application to a substrate in a thin layer which is converted to an opaque solid film after application. Used for protection, decoration or identification, or to serve some functional purpose such as the filling or concealing of surface irregularities, the modification of light and heat radiation characteristics, etc.

Paraffins

Completely saturated hydrocarbons characterized by chain structure. Poorest solvency of the hydrocarbon solvents. Least odor.

Pastel

A tint. A masstone to which white has been added.

Patina

A thin layer or corrosion, usually brown or green, that appears on copper or copper alloys, such as bronze, as a result of natural or artificial oxidization. In general, a patina is the sheen produced by age and use on any antique surface.

Picture Framing

The tendency of a material to pull away from the center of a substrate and gather at the sharp edges.

Pigment

A finely divided, colored substance which imparts its color effect to another material either when mixed intimately with it or when applied over its surface in a thin layer. When a pigment is mixed or ground in a liquid vehicle to form a paint, it does not dissolve but remains dispersed or suspended in the liquid.

Pigment Load

The amount of dry pigment in a coating.

Pigment to Binder Ratio

The amount of dry pigment compared to the amount of resin solids.

Pinhole

A surface defect with the appearance of a blister that “popped” but did not flow out and appears as a small hole on the film.

Polyester Resins

A special type of alkyd resins, prepared from dicarboxylic acids and dihydroxy alcohols.

Polymer

A large molecule which is formed by chemically bonding monomers. Many times they can be further reacted to form larger polymers.

Pore Bleed

The migration of solvent and pigment out of the pores of wood after stain or filler has been applied.

Pot Life

The length of time in which a material is still usable after catalyzation.

Primary Colors

Red, yellow and blue.

Primer

First complete coat of paint applied to a surface. Designed to provide adequate adhesion to new surfaces. The type of primer varies with the surface, its condition, and the total painting system to be used.

Print Resistance

The ability of a recently cured coating to resist the imprint of an applied force.

R
R
Recoatability

The ability to apply a fresh coat of material over a cured dry coat without lifting or loss of adhesion.

Relative Evaporation Rate

The evaporation rate of a solvent compared to a standard, usually n-butyl acetate, with the rate of n-butyl acetate set equal to 1.00. Solvents which evaporate faster than n-butyl acetate have a relative evaporation rate greater than one. Those which evaporate more slowly have a relative evaporation rate less than one.

Repairability

The ability to physically remove and repair defects from a coating’s surface.

Rheology

The term which is used to describe the flow, viscosity and thixotrophy of a material.

Roping

A shear-related surface defect a coating forms when it is transferred from a roll applicator to the substrate.

Rubbability

The ability to easily rub or polish a coating without leaving surface defects or haze.

S
S
Sags

Areas of uneven coating produced by flow of excessively thick layers of wet material.

Sandability

The ease at which a coating can be sanded without dragging or gumming the sanding medium.

Saturation

The percentage of reflected light which is colored.

Sealer

A coating which slightly raises the wood grain fiber and seals the wood grain fiber and seals the wood. Upon sanding it leaves a smooth surface and provides build.

Secondary Colors

Orange, green and violet. Mixtures of primary colors.

Shade

A color toned with black or with a complementary color having some degree of dulling effect.

Shelf Life

The period of time during which a material may be stored and remain suitable for use.

Shellac

Orange colored resin which is the secretion of the Lac beetle found in greater quantities in India and Indochina. Shellac is ordinarily dissolved in denatured ethyl alcohol.

Shrinkage

Usually associated with extensively crosslinked films, visible by the amount of curling induced on the substrate.

Slip

The degree to which tactile friction is absent from a film.

Solubility Parameter

A measure of solvency whose major usefulness is in predicting whether a particular solvent will dissolve a particular resin. Based on heat of vaporization of the solvent. Stronger solvents generally have higher solubility parameter values.

Solvent

A liquid, usually volatile, which is used in the manufacture of coatings, to dissolve or disperse the film-forming constituents and which evaporate during drying (does not become part of the dried film). Solvents are used to control the viscosity and application properties of the finished material.

Solvent (Active)

A solvent which by itself will dissolve a resin.

Solvent Power

A general term denoting the ability of a solvent to dissolve a resin or binder and hold it in solution. Also known as solvency.

Spatter (Flyspeck)

Small specks of color lightly splattered onto a surface to add aesthetics.

Spectrum

The bands of color seen when white light, especially light from the sun, is broken up by refraction, as in a rainbow or prism.

Sprayability

The degree to which a coating can be finely atomized at the tip of a spray gun.

Stain

A pigmented material which can be sprayed or wiped onto wood to accent the grain patterns.

T
T
Telegraphing / Ghosting

The transmitting of surface irregularities in a previous coat through to a topcoat.

Thermoplastic Resin

Resin which remains fluid on heating and hardens when cooled. Remains soluble in the original solvent blend and does not become insoluble upon heating.

Thermosetting Resin

Resin which polymerizes to a permanently solid and infusible state upon the application of heat. Once heated, will not dissolve in the original solvent blend.

Thinner (Reducer)

A blend of solvents used to lower the viscosity of the coating prior to application.

Thixotropy

The tendency of a coating to be low in viscosity under agitation but to “body-up” or become viscous when not agitated.

Toughness

The ability of a film to absorb physical abuse without failure.

Transfer Efficiency

The difference between the amount of finishing material solids deposited onto the surface of the part compared to the total amount of finishing material solids sprayed.

U
U
Ultra-Violet Light

The light rays which are outside of the visible spectrum at its violet end.

Urethane Grade

Any substance which contains active hydrogens capable of reacting with isocyanate will be restricted to very low levels. Specifications for urethane grade solvents typically center on very low water and alcohol contents, typically 0.1% water or less. Glycol ethers also contain active hydrogens and are not suitable for use in urethanes. Historically, esters have contained significant amounts of alcohol. More recently, alcohol free grades of esters have been produced with the designation “Urethane Grade”. The usual quality grades of hydrocarbons and ketones ordinarily are suitable for urethanes, even though they may not be designated specifically as urethane grade.

Urethane Resins

Materials based on isocyanate monomer reacted with other materials to yield polymers containing any ratio of urethane linkages, active isocyanate groups or polyisocyanate monomer. The resin may contain excess isocyanate groups available for further reaction at the time of application or may contain essentially no free isocyanate as supplied.

UV Cure

The crosslinking of a material upon exposure to ultraviolet radiation.

UV Resistance

The crosslinking of a material upon exposure to ultraviolet radiation.

V
V
Varnish

A liquid composition which is converted to a transparent solid film after application as a thin layer. Once the film has completely dried, it will no longer dissolve in the solvent blend from which it was applied.The resistance a cured film has against yellowing or chalking when exposed to ultraviolet radiation.

Veneer Crack

A crack that forms along the wood grain in a veneered substrate which subsequently cracks the coating surface.

Vinyl Resins

Resins based on vinyl chloride monomer. Most frequently copolymerized with other monomers such as vinyl acetate. Most vinyl resins require very strong solvents, such as ketones, to form useful solutions.

Viscosity

The degree to which a coating resists flow or movement.

Viscosity Cup

Instrument used to measure the rate of flow or movement of a material. Measured in elapsed time a material requires to pass through a given opening at a given temperature.

VOC

The weight of volatile organic material in 1-gallon of coating.

Volatile

Any material which can evaporate under normal operating conditions.

W
W
Washcoat

A low-solids coating applied under a stain to limit penetration of the pigments into the wood.

Wipe Stain

A pigmented material which can be sprayed or wiped onto wood to color it and to accent grain patterns.

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Our extensive wood coatings expertise covers all technologies. From pre-catalyzed to waterborne, nitrocellulose to polyurethane, we deliver a wide range of top-performing products for your business.

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