- American National Standards Institute.
ASTM - American Society for Testing and Materials.
Abrasive - Agent used for abrasive blast cleaning, i.e., sand,
grit, steel shot, glass beads.
Adhesion - Bonding
strength. Attraction of coating to the surface to which it is applied.
Property that causes one material to stick to another. (Adhesion is
affected by the condition of the surface to be coated, by closeness of
contact, as well as by molecular forces of unlike substances. The
surface being coated should allow a certain amount of penetration, be
chemically clean, not too smooth, and be hard, or non-porous, to achieve
Anchor Pattern -
Profile of a surface--usually attained by blasting.
Applicator - Tool
for applying or one who applies coating material.
Atom - The
smallest unit of an element.
Atomization - The
separation of powder particles into air.
Atomizing Air -
Air injected into powder path to atomize them into a mist or cloud.
Back Ionization -
Condition occurring when excessive build-up of charged powder particles
limits further powder from being deposited on the substrate. Back
ionization may occur during electrostatic applications and can reverse
the electrical charge of the surface layer of powder particles. This
condition may also be referred to as "electrostatic rejection" and/or
Blast Angle -
Angle of nozzle with reference to a surface. Also angle or particle
propelled from rotating blast cleaning wheel with reference to a
Blast Cleaning -
Cleaning with air- or jet-propelled abrasive.
Containment or recovery of emissions from a coating process for the
purpose of exhaustion through a control device or stack. (EPA
Capture Air Velocity
- Average speed of air drawn through booth openings.
Capture Air Volume
- Volume of air needed to capture oversprayed powder within a booth.
Capture Device -
Means of collecting pollutants for direction into a control device for
- That portion of overspray which is entrapped by the collector media
versus that which is discharged in exhaust air.
Cartridge Booth -
A type of powder booth which incorporates a cartridge filter system
within the booths.
Cartridge Filter -
Pre-assembled filter media which has been fluted, convoluted, and/or
made in cylindrical or canister form.
Degradation (decomposition) of a paint film by the gradual erosion of
its binder -- a loose powder forms on the surface and is easily
detectable by wiping the film.
Coating - Surface
covering. Paint, barrier. Film applied in a thin layer for protection
and decorative purposes. (Powder Coatings include Vinyl, Nylon, Epoxy,
Polyester, Polyurethane, and other chemistries.)
Color Fast -
Non-fading. Ability to retain original color.
Capable of being mixed easily without causing surface or chemical
defects. (May also pertain to the adherence ability of dissimilar
coatings to each other, or a coating to a substrate.)
- Coating which meets all air (VOC), water, and waste disposal
Device which converts mechanical force and motion into pneumatic, or
Corrosion - Decay.
Oxidation or deterioration due to interaction with the environment.
Cross Hatch - Test
to demonstrate adhesion characteristics of a paint or powder coated
surface -- performed by scribing a cross-hatch pattern at specific
intervals -- then applying and pulling area with tape.
Cross-Linking - A
particular method by which chemicals unite to form films.
Cure - To change
the physical properties of a material through chemical reaction by means
of condensation, polymerization, or vulcanization. (Curing is usually
accomplished by the action of heat and catalysts, alone or in
combination, with or without pressure.)
Cure Agent -
Hardener or cross-linking agent.
Cure Schedule -
The time/temperature relationship required to properly cross-link a
thermosetting liquid or powder coating.
Curing Oven -
Heated chamber for the purpose of solidifying a coating by either
chemical cross-linking or drying.
Coating - Powder coating for cosmetic appearance.
Deionized Water -
Water containing no ions. (Usually produced through the use of ion
Separation of two layers of coating.
Delivery - Process
of moving a coating through application equipment to the end product.
Dip Coating -
Coating by immersing the object in a tank of coating and then
withdrawing the object.
Downdraft Booth -
Spray booth in which air movement is from ceiling to floor.
Dry Blending -
Process for powder coatings manufacture where materials are blended in
dry form without melting.
Edge Coverage - A
powder coating's ability to form a continuous film over sharp edges,
corners, and angles.
Deposition - Attraction. Technique of moving and charging powder
coatings so that it is deposited onto a a grounded surface.
Bed - Fluid bed equipped with an electrostatic grid to charge the
powder. Deposition method of charging fluidized powder so that it is
deposited onto a grounded substrate.
"Environmental Protection Agency."
Etching - Surface
preparation of metal by chemical process. Removal of a layer of the base
Extension Gun -
Pole gun--extension adapter to a gun.
Extruder - Device
used to melt-mix plastics and powder coatings.
Face Velocity -
Air movement or velocity measured at booth openings. Average speed of
air that is drawn through the booth openings measured in FPM.
Fading - Reduction
in brightness or color. Gradual loss of color of a powder film due to a
chemical or physical change.
Fan Pattern -
Geometry or shape of spray pattern.
Faraday Cage Effect
- Phenomenon by which charged particles are prevented from entering
recessed areas. (Faraday Cage Effect is due to the curvature of electric
force lines to the nearest grounded surface.) - Michael Faraday.
Fatty Edge - Thick
edge sometimes found on heavily coated work resulting in a rounded,
thicker film along the edges.
- Corrosion or creep resembling a thread-like formation. (Filiform
corrosion is generally caused by poor substrate cleaning or rinsing.)
Filler - Extender,
bulking agent, or inert pigment.
Film Integrity -
Degree of continuity of film.
Film Thickness -
Depth of applied coating--expressed in mils, i.e., 1/1000 inch.
Film Thickness Gauge
- Device for measuring film thickness--available for both wet and dry
Filter - Strainer -
Purifier - Device for the removal of particulates from air, gas, or
a fluid stream.
Fines - Extremely
fine part of powder coatings. (15 microns or finer.)
Disintegration into small pieces or "flakes." Ref. "Scaling."
Flame Cleaning -
Method of surface preparation of steel using flame to burn off
Flash Point -
Lowest temperature at which a given flammable material will "flash" if a
flame or spark is present.
Flash Rusting -
Very thin film of rust occurring within minutes to several hours after
Flat Spray Nozzle
- Powder gun tip which gives a "fan pattern."
Fluid Bed -
Cylindrical or box-type chamber equipped with a porous membrane floor,
an air chamber, and an air supply. (Powder is suspended in the fluid bed
to form a fluid-like suspension. Powder coatings may be applied to "hot"
parts by dipping them into the powder/air mixture in the fluid bed.
Generally heavier coatings of 6-10 mils are applied with this method.
Fluid beds are also used as a reservoir to convey, or pump, powder to
Fusion - The
melting and flow of individual powder particles under the influence of
heat to form a continuous bond.
Fusion Point -
Temperature at which powder is melted by heat to form a liquid film.
Reaction rate of a given thermoset powder from the time it melts until
it becomes a semi-solid.
Glass Plate Flow -
The measurement of flow-out, or viscosity, when powder is in a molten
Gloss - Degree of
which a surface reflects light. Shininess, luster, or the ability to
reflect in mirror direction. (Glossy surfaces are generally very
Gloss Retention -
Ability to retain the original gloss.
Device for subjecting a painted panel to impact from air blown gravel to
determine its probable service life and method of failure. The extent of
failure is determined by counting the number of chips in each of several
Grind - Size of
Grit - Abrasive
obtained from slag and various other materials.
Electrical grounding of an item.
Ground Wire - Wire
attached to dissipate electrostatic charge on electrical equipment.
Hardness - Ability
of a dry paint film to withstand indentation.
Hiding Power -
Ability of a powder to mask the color or pattern of a surface.
High Film Build -
Producing thick films per coat.
Holiday - Pinhole.
Skip. Discontinuity. Void.
Holiday Detector -
Device used for the detection of pinholes or "holidays."
Hot Plate Melt Flow
- Measurement of flow-out or viscosity when powder is in the molten
Humidity - A
measure of the amount of moisture in the air.
Hybrid - An
epoxy-modified polyester or an epoxy-modified acrylic thermoset powder
Impact Fusion -
Tendency of finely divided powders to combine with other particles via
bombardment or friction during an application process and form hard
Inability to mix with or adhere to another material.
Infrared Oven -
Oven using series of lights or reflectors emitting infrared energy to
heat cure parts.
- Those employing inorganic binders or vehicles.
- A coating's ability to adhere to previously applied films.
Iron Phosphate Coating
- Pretreatment. Chemical deposition on steel for corrosion protection.
- Urethane resins. Urethane curing agents.
Ketone - Flammable
Leveling - Ability
of film to flow out to a smooth, uniform thickness.
Low Film Build -
Coating which is too thin.
Makeup Air - Fresh
air, drawn into a plant from an outside source, to replace the
solvent-laden air (from a coating operation or drying oven) being
exhausted from the building.
Mandrel Test -
Physical bending test for testing paint adhesion and flexibility.
Masking - Covering
areas not to be coated.
Material Safety Data
Sheet - Information supplied by coating manufacturers listing all
hazardous ingredients, physical and health hazards, first-aid
procedures, and protective equipment.
MEC - "Minimum
Melt Blend Powder
- Process of mixing all ingredients while molten.
Melt Mixing -
Temperature at which a finely divided powder will begin to melt and
flow. "Flow Stage."
Metallic Finish -
Finish utilizing metal powder as its hiding portion.
Mill Scale - Oxide
layer formed on steel by hot rolling.
Molecule - The
smallest particle of a substance that can exist without losing its
chemical form. (Molecules consist of one or more atoms.)
Molten Salt Bath -
A container of melted inorganic salts used to oxidatively remove paint
from a metal surface. (Part is dipped in bath and paint is burned away
Containing no iron.
Nylon - A
thermoplastic powder coating which contains long-chain polymers
consisting of recurring amide groups (CONH2).
Opacity - ... of a
film. Ability to cover, or hide -- especially as in the covering of a
substrate or previous coat(s).
Orange Peel - An
irregularity in the surface of a coating film resulting from the
inability of the film to "level out," or become smooth after being
Substance containing carbon compounds.
Orifice - Opening.
Oven - Chamber or
enclosed compartment for the purpose of baking, heating, or curing.
Overbake - Result
of curing coating film at too high a combination of time and
Overcoat - Second
coat. Top coat.
Particle Size -
Average diameter of powder particles measured in mesh size or microns.
Conversion of a metal surface to a less reactive state. A process used
to reduce the corrosion rate of metal surfaces.
Phosphatize - To
form a thin, inert phosphate coating on the surface -- usually by
treatment with phosphoric acid or other phosphate compound.
Pickling - The use
of a chemical solution to prepare a surface for coating or bonding by
dissolving away surface oxides and other impurities -- a certain amount
of base metal may also be removed.
Picture Framing -
Process of coating film pulling away from the edge of a coated surface.
Pigment - Dry
color matter -- usually an insoluble powder to be mixed with water, oil,
or other base for the production of paint or other products.
Formation of small holes through the entire thickness of a coating.
Formation of small, usually shallow depressions, cavities, or holes in a
Chemical reaction in which small molecules combine to form large
Porosity - Degree
of integrity or continuity.
Extended heating of a part after powder coating to complete the cure
Heating of an object after coating with powder.
Powder Coating -
Protective and/or decorative coatings formed by application of powder to
a substrate, after which the powder is fused into a continuous film by
the application or heat or radiant energy.
Preheat - Heating
of an object prior to coating.
Chemical alteration of a surface to make it suitable for application of
paint or powder.
Profile - Surface
contour of a blast-cleaned surface as viewed from edge cross-section of
Profile Depth -
Average distance between top of peaks and bottom of valleys on a
Quench - To
rapidly cool by means of liquid immersion--usually water or forced air
Radiation Cure -
Curing or drying a coating by means of exposure to electromagnetic waves
or particles such as infrared, ultraviolet, or electron beam.
Reclaim - Process
to recycle non-deposited powder through a delivery system for reuse.
Reclaimed Powder -
Powder which has been oversprayed and collected for reuse.
Recoat - Process
of refinishing or refurbishing rejected parts by sanding the blemished
area and respraying to salvage the part.
Recoat Time - Time
interval needed between the application of successive coats.
Recovery - Process
of removing non-deposited powder from air prior to recirculating powder
through the delivery system.
Recycled Powder -
Powder which has been oversprayed, collected, and conditioned for reuse.
Degree of light reflectance.
Resin - Film
former. Material (natural or synthetic) contained in varnishes,
lacquers, and other protective coating materials.
Safety breathing mask.
Reverse Osmosis -
Method of removing metal ions from an aqueous solution via
Runs - Curtains.
Rust - Corroded
iron. Red iron oxide deposited on metal. Also other metal oxides formed
Salt Spray Test -
Corrosion test using salt (NaCl) sprayed as a mist in a heated humidity
chamber to simulate seashore conditions, or to accelerate corrosion at a
controlled rate. ASTM B117.
Sandblast - Blast
cleaning using sand as an abrasive.
Scale - Rust
occurring in thin layers--commonly found on hot rolled steel.
Sealed Coating -
Primer. Coating used for the prevention of excessive absorption of a
first coat of paint by the substrate.
Formation of small agglomerates or gel particles in a coating.
Shelf Life -
Maximum interval a material may be stored and still be in usable
Shot Blasting -
Blast cleaning using steel shot as the abrasive.
Solution - Mixture
formed when one material (solid or liquid) is dissolved into a liquid.
- All operation necessary to prepare a surface to receive a coating of
Taber Abraser - An
instrument used to determine the abrasion resistance of a plastic or
paint coating. (Taber abrasers utilize rubber wheels impregnated with an
abrasive media. Results are reported in cycles to failure and/or weight
loss per specified cycles per specified weight load.)
Tape Adhesion -
Test used to check for adhesion of a paint to a surface. (Paint is
scribed with an "x" or a cross-hatch line pattern, tape is then applied
over the scribed areas, and ripped away to be examined for paint pulled
from the surface.)
TGIC Polyester -
Type of polymer which softens and melts when heated but resolidifies
Thermosets - Type
of polymer which does not soften appreciably when heated.
Tooth - Profile.
Mechanical anchorage. Surface roughness.
Topcoat - Usually
the final paint film applied to a surface.
- Ratio of the liquid paint or powder Coating actually deposited on a
substrate as compared to the amount directed at the part to be coated.
The process of creating a static electric charge on powder particles by
friction against a non-conductive material.
Venturi - A
constricted throat in the air passage of powder pumps and used to
determine velocities by the measurement of differential pressures
generated at the throat as powder traverses the tube.
Virgin Powder -
Unsprayed powder -- as opposed to sprayed or reclaim powder.
Voltage Tester -
Instrument used to measure voltage output at corona tip of electrostatic
Instrument used to measure electrical current in volts (voltage).
Water Blasting -
Blast cleaning using high velocity water.
Water Spotting -
The occurrence of whitish blemishes on a surface in areas where water
droplets have dried leaving mineral solids behind. i.e. salt, calcium.
White Blast -
Blast cleaning to white metal.
Wrap - A
characteristic of liquid or powder coatings in an electrostatic
application to seek out and adhere to parts of the substrate not in
direct line of sight of the delivery system end point