Technical data

GLOSSARY
A
ACCELERATOR — A substance which speeds up the
polymerization of a synthetic resin.
ACRYLIC RESIN — Any of a group of transparent
thermo-plastic resins formed by polymerizing esters of
acrylic acid or methacrylic acid.
ALIPHATIC — An organic chemical whose carbon atoms
are not in a ring form. A straight-chain compound. Mineral
spirits, some naphthas, and kerosene are typical aliphatic
compounds.
ALKYD RESIN — One of the major synthetics formed by
polybasic acid reaction with polyhydric alcohols. Primarily
used in enamels but also in combinations in some other
types of coatings.
ALLIGATORING — A condition where cracks in the film
are caused by contraction of the coating when a sudden
change in temperature occurs during drying. It may also
occur because of insufficient drying time between lacquer
coats, or because of poor penetration or wetting, or when a
hard topcoat has been applied over a soft undercoat. These
cracks usually penetrate to the metal surface.
AMINE — An organic chemical containing carbon hydro-
gen and nitrogen. Certain amines may be used as convertors
for epoxy resins.
ANHYDROUS — Containing no water.
AROMATIC — An organic chemical possessing the ben-
zene ring structure. Benzene and toluene are typical aro-
matic hydrocarbons.
B
BAKING FINISH — Any paint or varnish which requires
temperatures in excess of 150° F for the development of
desired properties. The usual baking difficulties are the
result of over-baking or under-baking schedules. Over-
baking will result in a hard, brittle film with less adhesion
than requirements demand. Proper correction of baking
faults demands strict adherence to the instructions of the
manufacturer.
BINDER — The non-volatile portion of a coating vehicle.
It generally consists of drying oils, resins, or combinations
thereof.
BLEEDING — A condition caused by pigments or dyes in
the under surfaces floating up into the top coating. Bleeding
may occur when material is applied with unclean spraying
equipment or when a topcoat/second coat is applied too
soon.
BLISTERING (OR BUBBLING) — Blistering may occur
when there is poor air circulation during drying of the
coating. Unbalanced solvents in the structure of the coating
will also cause this effect. Temperature differences between
the part being sprayed and the coating will also cause air
pockets or blisters. Water in air lines can cause blistering,
and daily draining of the water filters on air lines will help
minimize this problem.
BLOOMING (OR HAZING) — The appearance of
blooming is similar to blushing, though the underlying
reasons are different. Blooming is the result of rubbing the
finish too soon after application, the use of too coarse an
abrasive or too hard a rubbing stroke. When blooming does
occur, it may be removed by washing with a mild soap
solution and warm water, followed by chamois skin. Prop-
erly dried and hardened surfaces will not bloom when
rubbed or polished.
BLUSHING — Commonly referred to as clouding or whit-
ening, blushing is the result of moisture being present on the
film surface during the drying period. Although the fault
commonly lies in improper drainage of the air line during
finishing operations, the condition is also caused by high
humidity conditions within the finishing room. Improper
selection of solvents will also cause blushing.
BODY OF PAINT — The liquid portion without the vola-
tile solvents and water.
BODYING — See Gelling.
BROWN SPOTS — Spots which occur in a lacquer film
when oil is permitted to get into the material. As a
precautionary measure, drain the water and oil separators
daily.
BUBBLES — When improper quality or quantity of thinner
is used, bubbles often occur (also known as “solvent pop”).
To help prevent this defect, use correct proportions of
thinner at all times. Application of a topcoat before the
initial coat has cored properly or at too high a temperature
can also cause bubbles.
BUCKLING — A nitrocellulose lacquer film may shrink or
buckle when sprayed over an oil base undercoat. If neces-
sary to overcoat oil paint with lacquer, make the first top
coat as light as possible.
TO 1-1-8
Change 3 Glossary 1