INTD 54

paint

components of paint

•pigments—give color to coating•binders—holds the pigments particles together; provide washability/scrubbability & durability•solvents—make the coating wet enough to spread•additives—perform special functions

paint

solvent-based:•use petroleum derivative as solvent•take longer to dry—solvent evaporation•sometimes referred to as oil-based

water-based:•use water to make paint easier to spread•sometimes referred to as latex, acrylic latex & vinyl acrylic•adapt well to changing weather conditions—moisture less likely to build up

paint

several finishes/lusters available in alkyds or latex:•flat—highest PVC; provide velvety appearance; little washability•eggshell, pearl or satin—slightly lower PVC than flat; moderate scrubbability•semi-gloss—mid-range sheen; good scrubbability•gloss or high gloss—low-PVC; shiny surface; easy washability; shows imperfections•enamel—generally used to indicate a higher quality paint; greater durability; smoother finish

*PVC—pigment volume concentration

stain

also contain all four ingredients—have a unique binder which causes coating to penetrate deep into surface

•solid color stain—wood texture visible; hides grain; appears uniform•semi-transparent—both texture and grain visible

stain waxes—stain & waxin one process

clear coating

group of products that contain little or no pigmentsproduce wet or shiny appearanceprovide an extra layer of protection

urethane/polyurethane coatings form tough, hard, flexible chemically resistant films

other finishes/coatings:•varnish•shellac•lacquer•danish oil

primersfirst coat applied to substrate—prepares surface

some also serve as sealers for porous substrates—wood, paper on gypsum board

prevent waste of paint—absorption or deep colors

flame-retardant paintsnot fireproof, do reduce flammability of substrate

use wherever greater fire protection needed

0-25 flame spread rating required most commercial

application methods

best available equipment should be used—poor quality tools result in poor quality job

brushes should have flagged bristles—load brush with more paint & help paint flow smoothly

•brushes—woodwork & uneven surfaces•spraying—cover large areas; 8-10 times faster•pads & rollers—do-it-yourself tools; remodeling without removing furniture

surface preparation

most important procedure to achieve good paint finish

80% of all coating failures—inadequate surface preparation

until late 1970s lead-based paints were used—renovations of buildings painted before late 1950s must be done by contractor trained in proper handling

surface preparation

wood—moisture; all cracks & nail holes filled; sanding

plaster—must be solid; no cracks; smooth and level

gypsum board—seams must be taped; nail/screw holes set & filled with spackle; filled areas sanded; brushed clean of particles before priming

metal—loose rust & paint removed before painting (sandblasting)

masonry—use block filler due to porous surface; masonry paint covers less surface than other types

writing paint specifications

way of legally covering both parties in the contract—no misunderstandings of responsibility if scope is clearly written out

•time requirement most important—penalty •surface preparation•high-performance paints •method of application•inspections•cleanup