Wood finishes

Woodell s scale Wooden barrels Wooden matches Wood fiberboards Wood fillers Wood finishing Wood flake boards Wood flour... 

With few exceptions, stains used in wood finishing are formulated to improve the appearance of the substrate. Unlike paints, sealers, and topcoats, stains are utilized either to accentuate the natural beauty of the wood or to hide inherent defects found in most species of wood. 

Color Mixing. The various types of dye powders used to make dye stains are blended to achieve the desired color. Most finishers purchase wood stains premixed to specified colors. In the wood-finishing industry, various shades of brown are the most common. These colors are usually blended from primary colors. Color-matching skills can be acquired only by practice, but the basic theory of color matching is relatively simple and easily understood. The basic theory of color matching can be demonstrated by using the color circle shown in Figure 1 (see Color). 

Provisions of the Clean Air Act have resulted in the regulation of certain wood finishing appHcations. Residential and Institutional Furniture and Kitchen Cabinet Industries are under regulations which specify the amount and types of solvent emissions allowed. The si2e and location of a finishing facihty determine the extent of the effect stemming from the regulations. 

A wide range of polyurethane-type products has become available in recent years for coating applications. These include simple solutions of linear polyurethanes, two-pot alkyd-isocyanate and polyether-isocyanate systems and a variety of prepolymer and adduct systems. The coatings can vary considerably in hardness and flexibility and find use mainly because of their toughness, abrasion resistance and flexibility. Uses include metal finishes in chemical plant, wood finishes for boats and sports equipment, finishes for rubber goods and rain-erosion-resistant coatings for aircraft. One type of coating is potentially competitive with PVC leathercloth. Both alkyd-di-isocyanate and adduct-diisocyanate compositions may be coated on to fabrics from solutions of controlled viscosity and solids content. Such coated fabrics are soft, flexible and, unlike PVC leathercloth, free from plasticisers. 

Wood finishes (doors, front panels of furniture, lamination and lacquer finishes)... 

Water-based UV systems are gaining the most acceptance where the finishing must look like a traditional lacquer or varnish. Most water-based UV finishes confain 30-35% solids. Currently, it appears that the optimum UV system is a combination of a 100% solids system and water-based system on many wood products. One hundred percent solids finishes are used for sealing and filling the wood. When the wood is filled or sealed as desired, it can be cured and immediately sanded. Then the water-based UV system is applied to get the traditional look without the VOCs and in fewer steps than a traditional wood finish. ... 

Toluene diisocyanate is commonly produced as a mixture of the 2,4- and 2,6-iso-niers, that is used as a monomer in the preparation of polyurethane foams, elastomers and coatings, as a cross-linking agent for nylon-6, and as a hardener in polyurethane adhesives and finishes. Polyurethane elastomers made from toluene diisocyanates are used in coated fabrics and clay-pipe seals. Polyurethane coatings made from toluene diisocyanates are used in floor finishes, wood finishes and sealers, and in coatings for aircraft, tank trucks, truck trailers and truck fleets (United States National Library of Medicine, 1997). 

PVB combinations with the thermoplastic resins nitrocellulose or shellac have been used as sealers for wood finishing. In these applications the PVB component adds flexibility and adhesion. Tough, optically clear blends have been made with aliphatic polyurethanes. Thermosets are prepared with cross-linkers that form covalent bonds with hydroxy] groups. 

The book opens with a paper on the structure and composition of wood to define the material under discussion and then considers molds, permeability, wood preservation, thermal deterioration and fire retard-ance, dimensional stability, adhesion, reconstituted wood boards such as fiberboard and particleboard, plywood, laminated beams, wood finishes, wood-polymer composites, and wood softening and forming. A final paper treats the common theme of wastewater management. Only one of the papers presented at the meeting is not included in this volume, and its subject of conventional wood preservation methods is adequately treated in detail elsewhere (e.g., Nicholas, D. D., Ed Wood Deterioration and Its Prevention by Preservative Treatments, 2 vols., Syracuse University Press, 1973). 

These conditions are more nearly approached with sugars than with salts, as shown in Figure 4 (31). Treatment of wood with aqueous sugar solutions containing a toxic agent was commercially practiced in England for a short period (32). The chief shortcoming was that the wood became damp at relative humidities above 80% and that adhesion of wood finishes was reduced. 

Weather affects the performance of wood finishes adversely. Both types of finish the film-forming (paints, varnishes) and the penetrating (stains, preservatives) are adversely affected by a combination of the following factors ... 

The adverse effects of weather on wood and wood finishes and resultant chemical and physical changes on wood surface will be reviewed and discussed in this work. In addition, recent research findings on surface pretreatment of wood for enhancing durability of applied finishes will be presented. 

Forest Products Laboratory, "Wood Finishing Blistering, Peeling and Cracking of House Paints from Moisture," 7 pp., USDA For. Serv. Res. Note FPL-0125, For. Prod. Lab.,... 

The principal application for butyl CELLOSOLVE is as a low evaporating solvent of choice in many industrial coatinqs applications including coil coating and wood finishing. Its acetic acid ester, butyl CELLOSOLVE acetate, finds use in similar applications as a coalescing aid in latex trade... 

Major uses for UV curing (room temperature) include use of flat stock-fillers in particle boards and hardwood flooring, and for high-gloss (no-wax) protective coatings for floor tiles, wood finishes, and other specialty uses. 

Perhaps the most extensive area of research in simple pretreatment systems to enhance the weathering properties of wood has involved application of inorganic salt solutions. Much of the early work in this field was undertaken at the U.S. Forest Products Laboratory in Madison, Wisconsin and was aimed at improving the performance of transparent finishes. Black [25] described an experimental chromate-based wood finish and Black and Mraz [26] discovered that both acid and ammoniacal-copper chromate treatments significantly improved the performance of clear finishes on western red cedar, redwood (Sequoia sempervirens), and Douglas fir plywood. Later research [27] demon-... 

In spite of vast research work on PUD-acrylic hybrids, a limited range of hybrids is currently available. Among the various systems, two types are of interest to the construction industry. The first type is suitable for concrete protection, in the form of coatings. The second type finds suitability for wood finishes for parquet floor lacquers. 

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