Glossary of Terms

Ever wonder what a term means that your local paint store uses on a regular basis.  Here is a comprehensive list of terms with definition for your viewing pleasure.  

Glossary of Terms

ABATEMENT The removal or complete encapsulation with non-permeable film over and old coating or component. Usually in relation to old lead coatings.
ACCELERATED WEATHERING A test procedure that simulates natural exterior weather conditions in an accelerated and intensified manor.
ACCELERATOR A chemical used to speed up chemical reactions.
ACRYLIC A type of synthetic polymer used as the binder for high-performance water-based paints and caulks. 100% acrylic latex’s have very good adhesion, flexibility, breath-ability, alkali resistance, and color and gloss retention. Acrylic resins result from the polymerization of derivatives of acrylic-acids, including esters of acrylic acid, methacrylic acid, acrylonitrile, and their co-polymers.
ACTIVATOR The curing component in a two-component coating system.
ADHESION The ability of a dry paint film or caulk to remain attached to the surface. Adhesion is probably the single most important property of a paint or caulk. The two main types of adhesion are mechanical and chemical. Mechanical adhesion or tooth is the bonding of two materials because of their proper interlocking geometrical shape. Chemical adhesion is the chemical reaction on the molecular level achieving a bond.
AIR DRYING The most common form of curing a coating, exposure to oxygen in the air and simple evaporation.
ALIPHATIC HYDROCARBONS A group of organic solvents that are composed of chains of carbon atoms. Paint thinner, mineral spirits and VM&P Naphtha are examples.
ALKALI BURN A condition that occurs when the alkalinity in fresh masonry causes the breakdown of a paint’s binder, resulting in color loss and overall deterioration of the paint film. Most likely to occur with vinyl-acrylic latex and oil-based paints applied to masonry surfaces that are less than a year old. Masonry surfaces should never be painted for at least 28 days and even then the pH should be checked. Primers like Eff-Stop or Super-Loc from Dunn-Edwards can shorten the time considerably.
ALKALI Compounds that have a pH value of 7 to 14. Inexpensive test kits can be used to check pH on site before painting. Certain primers can help prevent alkali burn on finish coats.
ALKYD RESIN Formulated by reacting polyalcohols and phthalic anhydride fatty acids. This resin is used in so-called “oil-base” solvent thinned paint.
ALLIGATORING A scaly pattern (like the hide of an alligator) that appears on paint due to the inability of the paint to bond to a glossy coating beneath it. The application of a hard coating over a soft primer will cause alligatoring. Too rapid re-coating will also cause this condition. Almost always alligatoring is associated with oil-based paints.
ALUMINUM PAINT A paint, usually solvent based, that contains aluminum particles and provides a metallic appearance.
AMINE A common curing agent for epoxy coatings.
ANILINE DYE A powder stain soluble in water, alcohol, and other solvents and used in interior wood stains.
ANTI-CORROSIVE PAINT A paint that is designed to minimize rust or corrosion when applied directly to metal.
ANTI-FOULING PAINT Specially formulated paint for surfaces such as boat hulls and piers. It discourages attachment and growth of marine plants and animals.
AROMATIC HYDROCARBONS Organic solvents that contain an unsaturated ring of carbon atoms. Benzene, toluene, and xylene are in this group. A stronger solvent than the aliphatic hydrocarbon class.
ASTM American Society for Testing Materials. The main organization that sets procedure for standardized testing of all types of materials including coatings.
BACK PRIMING Applying primer to the unexposed portions of a component such as wood siding to prevent moisture from penetration from the backside.
BACKER ROD A foam rod that is placed in joints deeper than ½ inch to fill in some space before the sealant is applied.
BINDER One of the three main components in paint: the binder, the vehicle, and the pigment. The binder holds the pigment particles into a uniform, continuous paint film, and makes the paint adhere to the surface. The nature and amount of binder helps determine most of the paint’s performance properties – wash-ability, toughness, adhesion, color retention, and durability.
BIOCIDE A paint additive to keep bacteria from spoiling the paint in the can, or to keep mildew from growing on the applied paint.
BLEACHING Loss of color, usually caused by ultra-violet light exposure.
BLISTERING Bubble shaped domes of paint usually caused by moisture under the paint film or heavy moisture on top of uncured paint film.
BLOCKING The sticking of two painted surfaces to each other such as a door and door casing or a window sash and sill. Most of the latex paints have this problem except a few of the top grade acrylics like Permasheen.
BLUSHING A milky or mottled look on a coating, usually lacquer, caused by spraying in too high humidity. This is “moisture” blushing. Improper selection of lacquer solvent can also result in the precipitation of some of the nonvolatile solids. This is “gum” blushing.
BOXING The mixing of all of the containers of the same product to ensure uniformity of color. A sound painting procedure followed by good journeymen for decades. Also called “batching”.
BREATHE The passing of moisture vapor through the paint film, usually measured in “perms.”
BRIDGING The formation of paint film over a crack or depression in the surface.
BRUSH OUTS Actual paint samples, usually on 8” by 11” photo paper to provided to architects, owners, decorators, and general contractors to give the exact color and sheen of a proposed coating.
BURNISHING The formation of shiny areas on a painted surface as a result of rubbing or washing.
CALCIUM CARBONATE A chalky natural material used as an extender or filler in paint.
CATHODIC PROTECTION Most paints protect by forming a barrier to protect the substrate from corrosive elements. However some coatings act like the zinc consumable anode in your water heater. Metal structures act like a battery with a cathode and anode and current. The anode will begin to corrode, so a good zinc rich coating system is the anode and slowly sacrifices itself to protect the other metals, usually steel, that are lower on the periodic table. This is cathodic protection.
CAUSTIC SODA Sodium Hydroxide.
CAUSTIC A strong alkaline material.
CEMENTIOUS COATING Any coating containing Portland cement.
CFCs Chlorofluorocarbons were used in aerosol paint products until 1978.
CHALKING Deterioration of the surface of an exterior paint upon weathering into a faded, powdery substance. Chalking must be removed by power washing or a cleaning solution prior to painting. There are a few primers or additives that can help with severe chalking problems.
CHECKING Short narrow crack patterns in the paint film. Checking in commonly seen when paint loses its flexibility over wood plywood and veneer substrates.
CHLORINATED RUBBER A resin formed by reacting rubber and chlorine gas. Used widely in Europe and as a swimming pool coating in the U.S.
CHROMA Chroma is the colors “purity.” When there is no white, black, or gray present in a color it has high chroma. These colors appear very vivid and pure.
CISSING A coatings problem where material floats away from part of the substrate usually due to contamination of some type. Fish eyeing and cratering are types of cissing.
COALESCENCE Coalescence means to “come together.” In latex paints coalescence cures the coating. Small globules of latex resin shaped like ping pong balls are suspended in a sticky liquid and then dispersed in water. The water in coalescence-cure coatings acts as a diluent rather than a true solvent. The mixture of the resin particles, the sticky liquid and the water make something called an emulsion. During the curing process, the water evaporates from the emulsion solution, leaving the resin particles and the sticky solution or coalescent aid on the substrate. During this time, the resin particles, still held together by the coalescent aid, bond together while their thickness begins to decline. This curing process can take several days. Temperature below 50 degrees cause problems with this cure process and freezing causes complete destruction of the film.
COALESCENT AID The small amount of solvent contained in latex coatings. It does not dissolve the latex resins but simply helps the resins flow together in the film formation process.
COHESION The bonding of s substance to itself. Adhesion is the bonding of the substance to another substance.
COLOR FLOAT The separation of one or more pigments in tinted paint. This pigment appears as streaks or patches on top of the solution. Can be caused by improper blending or overloading the base with colorant.
COPPER STAINS Stains from unsealed copper that can range from brown to yellow to green. A result of copper corrosion that deposits a variety of compounds on painted surfaces.
CRACKING The splitting of a dry paint or varnish film from aging or movement of the substrate.
CRATERING Bowl shaped depressions in a paint or varnish film.
CURTAINS Long horizontal runs in a coating film due to over-applying.
DE-GLOSSER A liquid preparation used to remove the sheen or gloss on an old coating to improve adhesion on the recoat.
DEW POINT The temperature at which water vapor in the air begins to condense.
DFT Dry film thickness usually expressed in mils (1/1000 of an inch). Can be measured with non-destructive electronic or magnetic gauges or destructive technique gauges such as a micrometer.
DIN CUP A cylindrical container of 100 cc with a funnel opening of 2, 4 or 8 mm diameter that is used to measure viscosity. The cup is filled and the discharge is timed at a standard of 20 degrees C.
DRAG Resistance during brush stroke indicating a need for more thinner, and extender, or other additive to insure proper film leveling and workability.
DRIER Metallic salts which accelerate oxidation.
DRY FALL/DRY FOG Rapidly drying paint that produces dry particles of over-spray for easier removal from unpainted surfaces.
DRYING OILS An oil that will dry hard when exposed to air. Linseed, tung, fish, and soybean oils are examples.
DRY-TO-RECOAT A film is considered dry for recoating when a second coat or top coat can be applied without the development of any film irregularities such as lifting or loss of adhesion of the first coat.
EFFERVESCENCE Rapid release of solvents that produces cratering or pinholing in the film.
EFFLORESCENCE Water-soluble salts which appear as a whitish powder on the surface of masonry. They are salts carried to the surface by moisture. They are often associated with leaks or weak points in the masonry unit.
ELECTROSTATIC SPRAY The spray application of paint where particles are charged causing them to be attracted to the grounded surface.
EMULSION A mixture in which one liquid is suspended uniformly throughout another liquid but not dissolved. Latex paint is often called an emulsion even though it is technically a dispersion.
ENAMEL The term is generally used for high quality, dirt-resistant paints used for high use areas such as kitchen, bathroom, doors, cabinetry, and trim. Sheen levels are generally from satin to gloss.
EPOXY ESTERS Epoxies modified with oil to produce a coating which will dry by oxidation and do not require a catalyst or converter. Not as hard or chemical resistant a catalyzed epoxies but better alkali and chemical resistance than oils or alkyds.
ETCHING Treating a surface with an acid to provide a better anchor for coating.
FAUX FINISHES Decorative finishes often used to simulate other types of material such a stone or wood. The term “faux” means false, fake or simulated. Types of faux (pronounced “foe”) finishes are sponging, ragging, stippling, dragging, combing, marbling, and wood graining. Glazes are usually used and both positive finishing (direct application) and negative finishing (partial removal) techniques are employed.
FERROUS METAL Metal that contains iron. Rust is one of the main concerns requiring proper surface preparation and priming.
FERRULE The metal holder that connects the handle portion of a brush to the bristles.
FINGERING A bad spray pattern that delivers paint heavier on one part of the fan. Also called “tails.”
FLASH POINT The temperature at which a flammable vapor will ignite mixed with air.
FLASHING Uneven gloss or sheen. Can be caused by improperly sealed surface, poor application technique, poorly blended material, or too high or low temperatures during drying.
FLATTENING AGENT An ingredient used in lacquers and varnishes to reduce the gloss.
GALVANIZED METAL Zinc coated cold-rolled steel commonly used in downspouts, flashing, gutters, roof jacks, and other exterior applications to prevent rusting. This thin layer of zinc is applied by electroplating or hot dipping. Special primers like Galv-Alum are mandatory as well as cleaning and etching of new galvanized to insure proper adhesion of topcoats. Cleaning new galvanized and aging for six months if possible is often recommended. Aged galvanized must be cleaned of “white rust” before painting.
GLAZING COMPOUND A putty compound used to seal glass panes into its frame.
GLAZING LIQUID A transparent or translucent liquid or vehicle (either water or solvent based) used to achieve various faux effects such as antiquing. Color is added and blending techniques are employed.
GLOSS RETENTION The ability of a coating, usually under exterior exposure, to maintain its original sheen or shininess. Weather, temperatures, sunlight, chemicals and pollutants all can effect gloss. Two part urethanes have excellent color and gloss retention followed by high end acrylics and lastly the alkyds.
GRAIN CRACKING Cracks that run parallel with the grain of the wood substrate.
GRAIN RAISING The swelling and standing up of short, broken wood fibers caused by the absorption of water.
GRAINING A faux technique that simulates wood grain by using special tools and brushes.
GRIT The number of squares per square inch in the mesh of the sieve that strains the abrasive particles for sandpaper. Very coarse (40, 60,80 grit), Coarse (100, 120, 150 grit), Medium (180, 200, 240 grit), Fine (320), Very fine (400, 500, 600), Ultra fine (800, 1000)
GYPSUM WALLBOARD Commonly used interior wallboard made of crystalline calcium sulfate. Also called sheetrock. The levels of gypsum wallboard finishing can effect the painting process dramatically. Many of so-called paint problems are sheetrock finishing problems. Photographing, banding, striping are common problems associated with the sheetrock taping, topping, and texturing. A full discussion of these areas will be a part of this web informational site.
GYPSUM Crystalline calcium sulfate used as an extender pigment in paint.
HEPA VACUUM High efficiency particulate air-filtered vacuum. Required in the removal of lead-contaminated dust.
HIDE The hiding power or “hide” is the ability of paint to obscure the surface over which it is applied. The main factor in hide is the amount and quality of the pigment in the paint. Titanium dioxide is the best pigment for wet and dry hide in today’s common coatings. Cheaper pigments such as clay, calcium carbonate and silica can adversely impact the hide as well as the overall paint quality.
HIGH BUILD Term referring to a type of paint that will produce a thick coat in a single application.
HOLDOUT A characteristic of paint film to dry to its proper sheen on an absorptive surface.
HOLIDAY Painter slang for uncoated portions of a finished surface. Also know a “skips”, “sundays” and “vacations.”
HUE This is what we usually mean when we ask “what color is that?” The property of color that we are actually asking about is “hue.” When we talk about colors that are red, yellow, green, and blue, we are talking about hue.
HVLP High Volume Low Pressure. A spray system that minimizes over-spray and bounce-back by high volumes of area carrying material a low pressures of only 8 to 12 psi. Works best with light bodied materials that do not have to be over-thinned.
HYDROPHILIC A substance which has an attraction or absorbs moisture. Hydrophobic is just the opposite.
INDUCTION TIME After the mixing of a two-component material, a period of time must be allowed to insure the chemical reaction has initiated. The data sheet will give the suggested time based on temperature conditions.
INORGANIC Compounds that do not contain carbon or are not of animal or vegetable origin. (i.e. minerals and salts)
INTUMESCENCE COATINGS Fire retarding coatings that swell under high heat to form an insulating barrier to protect the surface beneath.
K.U.’s Units of measurement in the Kreb-Stormer system for measuring the viscosity of paints.
LACQUER Synthetic thermoplastic film-forming material dissolved in organic solvent. Dries by solvent evaporation.
LAC The main component of shellac. Lac is a secretion of the lac beetle found in Asia. The secretion is harvested from tree branches and treated. The orange color is removed though boiling. The seed lack is further refined and eventually dissolved with alcohol to form shellac.
LAITANCE Fine particles on the surface of fresh concrete caused by the release of water to the surface.
LEAD A heavy metal element found in paints, piping, glazes and other common household items. Sixty-four million homes built before 1978 in the U.S. contain lead. Three-quarters of housing before 1980 contain lead. Pre-1950 houses have the greatest risk for contamination. Lead has been linked to developmental disorders especially in children. The presence of lead components can be tested by certified testers using dust wipes sampling, soil sampling, paint chip sampling, or XRF gun testing. Abatement by removal or encapsulation is done by certified workers. Blood testing is also done to determine lead levels in contaminated residents.
LEAD-FREE A legal term referring to less than 0.5% lead in industrial products and less than 0.06% lead in all consumer products.
LEAFING In coatings the alignment of pigment flakes (usually aluminum) in a flat plane like a pile of leaves or sheets of paper.
LEVELING Term describes the flowing out of a brushed or rolled coating where there are no bristle or stipple marks remaining. Quality paint, proper viscosity, good brushes, and sound painting technique are necessary for good leveling.
LID Painter terminology for a ceiling.
LIFTING Raising or wrinkling of a previous coat by a successive coat. Strong solvents in the top coat are often the reason.
LITHOPONE Barium sulfate and zinc sulfide. One of the early pigment substitutes for lead in paint.
LIVERING An increase in the viscosity of a coating into a rubbery or coagulated consistency.
LRV Light Reflective Value. The amount of light reflected from a painted surface.
MARBLING One of many faux finish techniques that imitates the color and design of natural marble stone.
MEK Methyl Ethyl Ketone, a highly volatile solvent with good solubility for most vinyls, urethanes and other coatings.
MIBK ethyl Isobutyl Ketone, solvent used with vinyls.
MICRON 1/1,000,000th of a meter.
MIL A unit of measurement equal to one onethousandth of an inch. Commonly used to measure wet or dry paint film thickness. Ordinary latex house paint is approximately 1 to 2 mils thick per coat. Elastomeric coatings often are 12 to 16 mils total dry film thickness.
MILDEW A fungus that grows given the proper moisture, temperature, and nutrients on painted and stained surfaces. Many strains, including some very toxic ones, are identifiable by local testing labs. The mildew should be killed and removed properly before recoating the substrate.
MILL SCALE byproduct of the hot fabrication of steel. It is an heavy oxide layer, bluish in appearance, that can be the cause of coating failure if not treated appropriately in the specification for coating.
MISCIBLE Capable of uniform blending.
MONOMER Material of low molecular weight and capable of combining with other substances and interlocking to form a polymer. A polymer may be a very large molecule where the structural units may be repeated many times. Vinyl resins are polymers.
MSDS Material Safety Data Sheets. A document provided by the manufacturer listing the safety and handling procedures and precautions for that specific material. Any hazardous substance that comprises one percent or more of the total volume of the product must be listed.
MUD-CRACKING A paint failure problem that looks like the bottom of a dried up mud hole with its characteristic cracking pattern. One cause is over application of the material.
MURIATIC ACID A diluted form of hydrochloric acid used for cleaning and breaking up the glaze on concrete.
NACE National Association of Corrosion Engineers, an organization that certifies coating inspectors and is a resource for latest information of corrosion and its control.
NAP The fuzzy fibrous portion of paint roller. Length of nap should be matched with the roughness of the substrate and the type of material being applied. Nap can be natural material such as lambswool or synthetic manufactured fiber.
NEUTRAL Neither acidic or alkaline, pH 7.
NON-BRIDGING PAINT A specially formulated paint like Acousticoat that will not cover the small holes in an acoustical tiled ceiling.
NONFERROUS Containing no iron. (i.e. copper, aluminum, brass, lead)
OIL LENGTH The percentage of oil by weight in the resin.
OLEORESIN Product like turpentine containing oil and resins derived plants.
OPACITY The ability to keep light from passing through. High opacity will obscure the substrate. The lower the opacity, the closer to transparency
ORANGE PEEL Light bumpy texture that looks like citrus out skin. Improper viscosity is usually the cause in a sprayed coating.
ORGANIC Carbon based substance derived from living matter.
OSHA Occupational Safety and Health Administration. OSHA is the federal agency that sets safety standards in the workplace.
OXALIC ACID One of the main chemicals along with sodium metasilicate that are used to restore, clean, and brighten old wooden decks
OXIDATION A chemical reaction with oxygen.
PAINT A coating to protect and improve the appearance of a surface. Made of a binder, pigments, vehicle, and various additives. The binder is the resin or the glue that hold the pigments together. The vehicle allow the binder and pigment to be applied in a workable liquid. The additives are small amounts of mildicide and other chemicals to improve the shelf-life, workability, flow, leveling, and other characteristics of the coating.
PERMEABLE Capable of allowing something (like water) to pass through. Some permeability in certain coatings is good. It allows moisture to pass through the film in small amounts rather than lifting the film because the water is trapped behind it. Special care must be taken when applying non-permeable coatings to seal all cracks, voids, and openings to prevent water from getting behind and underneath the film.
PHOSPHATIZE To treat steel with metal phosphates and phosphoric acid to temporarily inhibit rust.
PH pH 1 to 7 is acid, pH 7-14 is alkali.
PIGMENT Ground particles in paint formulation that add hardness, color, hide, and corrosion resistance.
PIN HOLING Tiny holes that go through the whole film. Waterproof coatings must be pin hole free.
POLYMERIZATION The combining of two or more molecules to form a more complex molecule, these new more complex groups are called polymers.
POLYURETHANE These are isocyante copolymers and are noted for their extreme hardness and durability. The two most common types are oil-modified urethanes and catalyzed aliphatic polyurethanes. Oil modified urethanes are a blend of urethane and drying oils and alkyds. They are one component, are very hard, and air-dry by the evaporation of solvents and oxidation of the oil. The catalyzed aliphatic polyurethanes are two component products that cure by reacting a polyol component (acrylic or polyester) with isocyanates. This class has excellent color and gloss retention.
POLYVINYL ACETATE The most commonly used resin in interior latex coatings.
POT LIFE The period of time at which the paint can be applied before solidification begins, especially in a catalyzed two-component system. Pot life is a function of temperature. Warming will shorten the pot life and cooling will extend the pot life.
POTABLE WATER Human drinking water. Tanks containing potable water require special NSF certified coatings.
PRIMARY COLORS Red, yellow, and blue.
PVC Pigment Volume Concentration. This is the percentage of pigment to the total volume of solids (the solids pigment and binder). Flat paints have 40 to 50% PVC while gloss and semi-gloss with have 10 to 25% PVC.
RAIN STREAKING The black or dark vertical lines of the face of gutters and other exterior metal surfaces. Usually caused by air pollutants tracked and deposited by dew, fog and rain and metal surfaces. More prevalent near main highways or high sources of air pollutants. Washing with a good cleaner may remove the stains but often repaint is necessary.
RELATIVE HUMIDITY The percentage of water vapor in the air in relation to the total amount of water the air can hold at the same temperature.
RESPIRATOR A mask worn to prevent breathing of toxic airborne particles. Various filtering materials are used including activated charcoal and fibrous filters. An effective respirator should be fitted properly and facial hair should be cleanly shaven.
RHEOLOGY The scientific study of the flow and deformation of liquids.
RUST Iron Oxide. The natural tendency of an element to return to its natural state. The natural state of the iron in steel products is iron oxide. The more energy that is required to refine and element, the greater the tendency to return to is natural state. Inhibiting corrosion is steel is a combination of preparation, priming, and coating with proper methods and products.
SAPONIFICATION The breaking down of oils into very fine droplets called colloids. The alkaline hydrolysis of fats whereby a soap is formed. The reaction of certain oils in oil-based coatings with alkaline substrates such as concrete or zinc-rich coatings will result in saponification. The reaction between alkyd paint and galvanized metal results in saponification and peeling.
SATURATION Intensity or saturation tells us how a color looks under certain lighting conditions. Over the course of the day, although the color in a room remains the same, the saturation will change. This is not lighter and darker as in chroma but rather pale or weak and pure or strong.
SECONDARY COLORS Orange, purple, and green.
SETTING-UP TIME The time required for the initial stage of drying of a finishing material, whereby it has lost its ability to flow, but is still soft and plastic.
SHEEN The degree of luster of the dried film of a finishing material. This is usually measured by the amount of light reflected at a 60 degree angle. Flat, 1 to 9%, Low Sheen, 10 to 25%, Eggshell, 26% to 40%, Semi-Gloss, 41-69%, Gloss, 70 to 89%, High Gloss, 90%+. This breakdown may vary depending on the paint company.
SIENNA An earth pigment of brownish yellow color when raw, or an orange-red or reddish brown when burnt. The color originates from the oxides of iron and manganese.
SILICA It is one of the most abundant constituents of the earth’s crust. It occurs in extensive deposits as “diatomaceous earth,” “kieselguhr” and “Tripoli”-the siliceous skeletons of microscopic algae deposited in ancient seabeds. It is used as an inert pigment, extender or filler in paints.
SKIN A solid layer of film formed on the surface of paint or varnish in the container. Caused by exposure to air.
SOFTWOOD, HARDWOOD Softwoods are characterized by having needles (fir, pine, spruce, redwood, cedar) and hardwoods have broad leaves. (oak, maple, mahogany)
SOLIDS BY VOLUME The percentage of a gallon of paint that remains after all the water or solvents have dissipated. This is what actually makes up the dry film. This number is a pretty good indicator of the quality of the paint and should be used to figure the true cost of paint—cost per square foot, NOT cost per gallon. For instance brand “A” cost $15 per gallon and is 30% solids by volume, and brand “B” is $15 per gallon but is 40% solids by volume. Brand “B” with actually cover 25% more area at the same film thickness than brand “A”. The cost per gallon is the same but the true cost for brand “A” is 25% higher. Solids by volume can be found on the data sheet supplied by your paint representative.
SOLVENT ENTRAPMENT The trapping of solvent under a cured paint film. Caused by improper drying conditions, over application, or recoating to soon.
SOLVENTS In coatings, this term is applied to products which dissolve or disperse the film forming materials. They usually volatize during drying and do not become part of the film itself. They are used to control the consistency and thus obtain suitable application properties. The five basic categories of the most common solvents are: 1. Aliphatic Hydrocarbons (mineral spirits, paint thinner), 2. Aromatic Hydrocarbons (toluol, xylol), 3. Ketones (acetone, MEK, MIBK), 4. Esters (ethyl acetone, butyl acetate, auryl acetate), 5. Alcohols (ethyl alcohol, isopropryl alcohol, butyl alcohol.
SPACKLE A common white paste filler material for small holes and voids that sand nicely and is paintable. The paste comes in two forms, regular and lightweight. The lightweight spackle shrinks less because it has less water content. It needs little sanding and can be painted immediately after application. Both are brittle and will crack in dynamic crack areas.
SPALLING The breaking up or chipping of a surface often by expansion and contraction.
SPAR VARNISH A very durable waterproofing varnish for severe exterior exposure. The word “spar” originates from the fact that comparatively durable varnish is applied to the spars of ships.
SPOT-PRIME Priming selected area only that have been repaired or priming porous areas to bring them up to the absorption level of the surrounding field.
SPRAY PAINTING The application of painting by breaking the paint up into small particles and carrying them to the substrate by pressure or air movement. Some types are convention air, airless, air-assisted airless, and high volume low pressure. Conventional air requires an air compressor and pressurized pot or canister. Airless spray forces the paint under 1500 to 3000 psi compression. Air-assisted is a hybrid of the first two.
SPREADING RATE The area over which a unit volume of paint is spread, usually expressed in square feet per gallon. The spread rate is also related to the thickness of the coating. A gallon of paint contains 231 cubic inches and will have a spread rate of 1604 square feet at one mil (1/1000th of and inch), wet film thickness. Multiply 1604 times the percentage of solids by volume to give the coverage rate dry at one mil thickness.
SSPC STANDARDS Steel Structures Painting Council Standards. Preparation methods for ferrous metals. SSPC-SP1 Solvent Cleaning, SSPC-SP2 Hand Tool Cleaning, SSPC-SP3 Power Tool Cleaning, SSPC-SP11 Power Tool Cleaning to Bare Metal, SSPC-SP5 White Metal Blast, SSPC-SP6 Commercial Blast, SSPC-SP7 Brush-Off Blast, SSPC-SP10 Near White Blast, SSPC-SP12 High and Ultra-High Pressure Water Jet Cleaning. SSI and NACE have similar standards.
STACKING A term similar to “wet on wet” where a second coat is sprayed on the first coat before the first coat is dried. This is done to minimize pinholing, and achieve higher build. Appropriate material, solvents, and time between coats is critical to avoid major problems.
STAIN BLOCKERS Many stains in substrates require special primers to keep them from penetrating the finish coat. Difficult stains include nicotine, smoke, oils, tannins (found in cedar and redwood), dyes, and water stains. Quick dry specialty stain blocking primers are very effective trapping these compounds in the prime coat. Some are water based but the most effective are the alkyd or shellac type.
STAIN solution of suspension of coloring matter in a vehicle designed primarily to be applied to the surface of articles to impart color effects, rather than to form a protective coating.
STATIC, DYNAMIC In describing cracks in structures, static cracks do not move, dynamic cracks have ongoing movement. Flexible fillers (such as elastomeric caulks) should be used in the dynamic cracks. Static cracks can be filled with hard compounds.
STIPPLED FINISH A finish with a slightly roughened or pebbled surface produced by striking the finish materials with ends of the bristles of a stiff brush or by the use of a specialty stipple roller while the material is still wet.
STRATIFICATION Delamination or inter-coat loss of adhesion. Usually this failure occurs when several coats of the same product have been applied after the recommended recoat time.
SUBSTRATE The bare surface or material to which the primer or coating is applied. (i.e. steel, wood, masonry, gypsum)
SURFACE DRYING When a coating dries on top but remains relatively soft on the bottom.
SURFACTANT An agent used to break down surface tension of liquids to make them more miscible, such as in oil and water emulsions. A component of universal colorants.
SURFACTANT Paint additive that breaks surface tension to improve wetting or disbursement of pigments.
TACK COAT A thin spray coat applied often to fill porous surfaces before a full coat is applied. Sound spray technique when coating zinc rich primers to avoid cratering and pin-holing.
TACK FREE That condition when a film or finishing material has reached a point that the surface can be touched lightly without the sensation of stickiness.
TANNINS Acidic dye found in cedar and redwood that requires a strong stain blocking primer keep from discoloring the top coat.
THERMOPLASTIC Coatings that can be returned to liquid state by applying solvents. These include lacquers, vinyls, acrylics, epoxy emulsions, and alkyds. The curing mechanisms are evaporation and coalescence.
THERMOSET A class of material which hardens and becomes insoluble and cannot be re-softened. These include expoxies and catalyzed urethanes. Polymerization or a chemical change of state is induced in several ways: 1. Heat induced, 2. Oxygen induced, 3. Evaporation induced, 4. Chemical induced, and 5. Hydration or water induced.
THINNERS Volatile liquids used to lower or otherwise regulate the consistency of paint and varnish.
THIXOTROPY False-bodied. The property of a material which causes it to change from a thick, pasty consistency to a fluid consistency upon agitation and to return to a thick pasty consistency upon subsequent rest.
TINTS, TONES, SHADES Tints are obtained by adding white to a pure hue, shades are obtained by adding black to a pure hue, and tones are made by adding gray to a pure hue.
TITANIUM DIOXIDE The stable oxide of the metal titanium, having the formula TiO2. High amounts of titanium dioxide are found in top grade paints. It increases both wet and dry hiding power and gives greater brightness to a finish. It is white in color. The anatase TiO2 is the chalking type and the rutile TiO2 is the non-chalking.
TOLUENE Also know as toluol. A colorless liquid in industrial pure grade is used as an aromatic solvent in lacquers and synthetic enamels. It is a strong solvent with a low flash point.
TOOTH The condition of a surface that allows the film of succeeding coats of finish material to adhere readily. Mechanical anchorage, surface roughness, rough surface profile.
TUNG OIL Also known as Chinawood Oil. A fast drying oil obtained from the nut of trees native to China, but also grown in the United States. The oil has a bacon-like odor and jells under the influence of heat and certain chemicals.
UMBER Ultraviolet Radiation. The part of the solar spectrum that damages paints and coatings. This process can be slowed with coating components called UV Absorbers.
VALUE The lightness or darkness of any color.
VAPOR BARRIER A water-proof layer which prevents any moisture to pass into a material or building.
VARNISH Any homogenous transparent or translucent liquid which, when applied as a thin film, dries on exposure to air to a continuous film, giving a decorative or protective coating to the surface to which it is applied. An oil varnish is one which dries by a combination of evaporation, oxidation, and/or polymerization.
VEHICLE The liquid portion of paint, enamel, or lacquer, consisting of film forming non-volatiles and volatile thinners. The vehicle allows the applicator to apply the pigment and resin to the substrate in a workable liquid form.
VERMILLION One of the oldest red to orange pigments having been used for centuries, first in China. It is a sulphide of mercury prepared by subliming mercury and sulphur together. Sometimes spelled “Vermillion.” Devoe and Reynolds, one of the oldest paint companies in the United States, made vermilion red famous by painting the early train cabooses vermilion red and starting a tradition that has lasted for many decades.
VERTICAL GRAIN As applied to wood it is another term for edge grain, where the grain is tight and runs from bottom to top of the plank as opposed to flat grain which runs mainly from side to side. Vertical grain is generally considered stronger than the same size board in a flat grain.
VINYL ACETATE A colorless liquid which is used as a monomer for the preparation of polymers and copolymers of vinyl acetate.
VINYL A generic name for a synthetic resin used to describe any polymer obtained by the polymerization of a monomer containing a vinyl group. Vinyl resins are generally thermoplastic, odorless, tasteless, colorless, and nonflammable or slow burning.
VISCOSITY A measure of fluidity of a liquid. A property of fluids which may be described as resistance to flow. It is measured by the amount of sheer resistance in the material.
VOC Volatile Organic Compound. For the majority of cases, the VOC in paints are the solvent. Air pollution regulations require the VOC to be listed on the data sheet. It is listed in grams per liter or pounds per gallon. Regulations can vary slightly from region to region.
WARM COLORS Any hue in which red-orange predominates. It is associated with heat, sunshine, and fire.
WATER, DIRT, & GLUE Basicly, Paint is water, dirt, and glue. Water is the vehicle, dirt is the pigment (mainly natural compounds from the ground), and glue is the resin or binder that holds it all together.
WETTING AGENTS Surface active agents. A name given to chemical compounds having both hydrophilic (water soluable) and hydrophobic (water repellent) groups. These compounds are used to lower the surface tension of water and aid in the formation of aqueous dispersions of oil and other water insoluble material. (see SURFACTANT)
WETTING Thorough disbursement of a liquid over and around a solid or through another liquid by using agents to break the surface tension
WFT Wet film thickness. Film thickness during application before vehicle or solvents have dissipated.
WHITE LEAD Compounds of lead used as white pigment in many types of paint. After the health dangers associated with lead in humans it has been replaced by primarily titanium dioxide in quality paints and talc, clay, diatomaceous earth, calcium carbonate and other types of filler or extender pigments.
WICKING The movement of liquid by capillary action. (i.e. The absorption of paint though the end grain of wood, or the movement of water up through the bottom of unsealed siding.)
WRINKLING The ripple-like distortion in the paint skin often caused by applying a new coat over an undried coat. Uncured alkyd exposed to cold and moisture, like on a metal gutter, can cause wrinkling.
XANTHIC COLORS Any hues having a yellow color or a color in which yellow predominates. A series of colors, particularly in flowers, beginning with yellow and running through orange and red. Sunflowers, dandelions, marigold, and jonquil belong to this group. Opposed to “cyanic.”
XYLENE An aromatic hydro-carbon used as a solvent for synthetic resins and industrial coatings. Also known as Xylol.
YELLOWING A condition that occurs in most oil base enamels over time. Whites can turn into a light amber color in light deprived areas in a few weeks or months. Exposure to ammonia in some cleaner can accelerate this yellowing. Going to a high-end acrylic like Permasheen is a good solution.
ZAHN VISCOMETER A scientific instrument used to measure the viscosity of industrial type finishing materials, to obtain uniform results.
ZINC OXIDE Also know a Chinese White and Zinc White. A white opaque pigment manufactured by oxidization of zinc metal by air to produce a crystalline pigment.
ZINC RICH PRIMER A primer using the principle of cathodic protection to protect iron and steel.