Paints

 

COATINGS & PAINTS PRINCIPAL TYPES OF COATINGS: 1. PAINTS - a mixture of a solid pigment suspended in a liquidvehicle, applied as a thin, usually opaque coating to a surface for protection and decoration.

2. STAINS – a solution of dye or suspension of pigment in a vehicle, applied to penetrate and color a wood surface without obscuring the grain.  grain. 

3. VARNISHES – a liquid preparation consisting of a resin dissolved in an oil (oil varnish) or in alcohol (spirit varnish), that when spread and allowed to dry forms a hard, lustrous, usually transparent coatings.

PAINT COMPOSITION: 1. PIGMENT  – a finely ground, insoluble substance suspended in a liquid vehicle to impart color and opacity to a paint.   “Varnish – no pigment”

2. VEHICLE - a liquid in which pigment is dispersed before being applied to a surface in order to control consistency, adhesion, gloss and durability.

3. BINDER – the nonvolatile part of a paint vehicle that bonds particles of pigment into a cohesive film during the drying process.   “Stain-no Binder”  

SOLVENT - the volatile part of a paint vehicle that evaporates during the drying process. PAINTS CLASSIFICATION: 1. ARCHITECTURAL PAINTS - are air-drying materials applied by brush or spray to architectural and structural surfaces and forms for decorative and protective purposes.

2. COMMERCIAL PAINTS - air-drying or baking-cured materials applied by brush, spray, or magnetic agglomeration to kitchen and laundry appliances, automobile, machinery, and furniture and used as highway marking materials.

3. INDUSTRIAL PAINTS - subdivided by their intended service: corrosion-resistant coatings, high temperature coatings, and coatings for immersion service  service  

4. ADDITIVES – Modifications.

PAINT TYPES: 1. PRIMERS - are basecoats applied to a surface to improve the adhesion of subsequent coats of paint or varnish. Also called prime coat.

2. SEALERS  –  a basecoat applied to a surface to reduce the absorption of subsequent coats of paint or varnish to prevent bleeding through the finish coat.

 

PAINT TYPES: 3. OIL PAINTS  PAINTS – a  – a paint in which the vehicle is a drying oil.

9. HEAT RESISTANT PAINTS  –  a paint specially formulated with silicone resins to withstand high temperatures.

* Drying Oil Oil - any of various oily, organic liquids, as linseed oil, that oxidizes and hardens to form a tough elastic film when exposed in a thin layer to air. 10. INTUMESCENT COATINGS - when exposed to the heat of a fire, swell to form a thick insulating layer of inert foam that retards flame spread and combustion 4.ALKYD PAINTS  PAINTS – apaint  – apaint in which the vehicle is an alkyd resin. * Alkyd resin resin - any of a group of synthetic resins derived from a polyvalent alcohol in reaction with an organic acid, used chiefly in adhesives and paints. STAIN TYPES: 1. WATER STAIN  – a penetrating stain made by dissolving dye in a water vehicle. 5. LATEX PAINTS  PAINTS – a  – a paint having a latex binder that coalesces as water evaporates frorn the emulsion. Also called RubberBase Paint, Water-Base Paint. * Latex – a water emulsion of synthetic rubber or plastic globules obtained by polymerization and used in paints and adhesives.

* Dye  Dye   –  –   a soluble coloring material that imparts color by absorption. * Penetrating stain  –  –   a  stain that penetrates a wood surface, leaving a very thin film on the surface.

6. EPOXY PAINTS - have an epoxy resin as a binder for increased resistance to corrosion, abrasion and chemicals.

2. SPIRIT STAIN – STAIN  – a  a penetrating stain made by dissolving dye in an alcohol or spirit vehicle.

7. ANTICORROSIVE PAINTPAINT- a paint or primer specially fornulated with rust-inhibiting pigments to prevent or reduce the corrosion of metal surfaces. Also called Rust-Inhibiting called  Rust-Inhibiting Paint.

3. PIGMENTED STAIN - is an oil stain containing pigments capable of obscuring the grain and texture of a wood surface.  Also called Opaque Stain.

8. FIRE RETARDANT PAINTS – a paint specially fornulated with silicone, polyvinyl chloride, or other subtance to reduce the flame-spread of a combustible material.

4. OIL STAIN - made by dissolving dye or suspending pigment in a drying oil or oil varnish vehicle.

 

VARNISHES TYPES:

New wood exteriors:

1. SPAR VARNISH - is a durable, weather-resistant varnish made from durable resins and linseed or tung oil. Also called Marine Varnish.

* The surface must be clean and dry * Rough spots in siding should be sanded smooth. * All new wood must be primed . * After the prime coat has been dried, putty and fill all nail holes and cracks. * Caulk joint around doors and window frames. * If pre-primed siding is hard and slick, it should be re-primed.

2. POLYURETHANE  POLYURETHANE  - an exceptionally hard, abrasion  –   –  resistant, and chemical  –   –  resistant varnish made from plastic resin of the same name.

Masonry floors: * Interior and exterior concrete floors must be allowed to dry approximately 90 days for proper aging. * Fresh cement contains alkali which will burn paint. * Floors subjected to excessive moisture seepage, or hydrostatic pressure, cannot be successfully painted.

3. LACQUER - refers to any of various clear or colored synthetic coatings consisting of nitrocellulose or other cellulose derivative dissolved in a solvent that dries by evaporation to form a high gloss film.

4. SHELLAC - spirit varnish made by dissolving purified lac flakes in denatured alcohol.   Also  Also called Shellac Varnish. Varnish.

Metal surfaces: * All metal surfaces must be cleaned and dry. * Remove any rust, mill scale or loose paint by wire brushing, sandblasting/sandpapering. * Bare spots on shop-coated steel must be wire - brushed and spot primed. * Remove oil and grease with paint thinner or mineral spirits. * No priming necessary when applying exterior latex to weathered galvanized metal. SURFACE PREPARATION (Interior): * The surface to be painted must be clean and free of wax, dirt or grease.

PAINTS CAN BE APPLIED BY: Brush, Spray, Roller SURFACE PREPARATION (Exterior):

* Cracks and holes must be repaired with patching plaster. * Patched areas must be spot primed. Old glossy surfaces should be prepared by sanding.

Previously painted surfaces: * Scrape off loose paint and sand smooth. * Old, fading paint must be removed to provide good adhesion for the new coats of paint. * Nail back loose boards, countersink the nail heads and fill with putty. * To prevent discoloration of paint later, seal knots and resinous spots with a thin coat of shellac.

PROPER APPLICATION: * Avoid painting in the hot sun. Try to paint those surfaces that have already been exposed to sunlight * Apply a coat of paint primer * Finish with two-coat of top coats

 

PAINT DEFECTS: 1. BLISTERING  BLISTERING  - Bubbles resulting from localized loss of adhesion and lifting of the paint film from the underlying surface.

8. SURFACTANT LEACHING LEACHING - Concentration of water-soluble ingredients on the surface of a latex paint, typically on a ceiling surface in rooms that have high humidity (e.g., shower, bathroom, kitchen); may be evident as tan or brown spots or areas, and can sometimes be glossy, soapy or sticky.

2. BLOCKING - Undesirable sticking together of two painted surfaces when pressed together (e.g., a door sticking to the  jamb).

9. WRINKLING - A - A rough, crinkled paint pa int surface, which occurs when uncured paint forms a "skin.”  "skin.”  

3. BURNISHING - Increase in gloss or sheen of paint film when subjected to rubbing, scrubbing or having an object brush up against it.

10. PEELING - Loss of paint due to poor adhesion. Where there is a primer and top coat, or multiple coats of paint, peeling may involve some or all coats.

4. CRACKING/FLAKING  CRACKING/FLAKING  - The splitting of a dry paint film through at least one coat as a result of aging, which ultimately will lead to complete failure of the paint. In its early stages, the problem appears as hairline cracks; in its later stages, flaking occurs.

11. CHALKING - Formation of fine powder on the surface of the paint film during weathering, which can cause color fading. Although some degree of chalking is a normal, desirable way for a paint film to wear, excessive film erosion can result in heavy chalking.

5. BUBBLING (FOAMING/CRATERING) - Formation of bubbles (foaming) and resulting small, round concave depressions (cratering) when bubbles break in a paint film, during paint application and drying.

12. EFFLORESCENCE/MOTTLING -Crusty, -Crusty, white salt deposits, leached from mortar or masonry as water passes through it.

6. LAPPING - appearance of a denser color or increased gloss where wet and dry layers overlap during paint application.

7. SAGGING SAGGING - Downward "drooping" movement of the paint film immediately after application, resulting in a uneven coating.

13. FROSTING -  A white, salt-like substance on the paint surface. Frosting can occur on any paint color, but it is less noticeable on white paint or light tints. On masonry, it can be mistakes for efflorescence.

14. ALLIGATORING - Patterned cracking in the surface of the paint film resembling the regular scales of an alligator.