Urethane lacquers

Urethane lacquers, 240 Urethane materials recycling of, 207-208 synthetic methods for, 246-258 Urethane oils, 202, 241 Urethane polymers, 197 Urethanes... 

Conformal coatings are used for PCAs that require exceptional resistance to moisture, solvents, or abrasion. A wide variety of polymers are used to perform this function, including phenolic, silicone and urethane lacquers and sUicone rubber, polystyrene, epoxy, and paraxylylene coatings. Epoxy and polyurethane-based coatings are the most commonly used. H conformal coatings are used in conjunction with a solder mask, they must be chemically compatible. - ... 

Pentaerythritol and trimethylolpropane acryUc esters are usefiti in solventiess lacquer formulations for radiation curing (qv), providing a cross-linking capabihty for the main film component, which is usually an acryUc ester of urethane, epoxy, or polyester. Some specialty films utilize dipentaerythritol and ditrimethylolpropane (94,95). 

Nitrocellulose based lacquers often contain short or medium oil alkyds to improve flexibiUty and adhesion. The most commonly used are short oil non drying alkyds. Amino resins or urethane resins with residual isocyanate functional groups may be added to cross-link the coating film for improved solvent and chemical resistance. The principal appHcations are furniture coatings, top lacquer for printed paper, and automotive refinishing primers. 

The acetates of most alcohols are also commercially available and have diverse uses. Because of their high solvent power, ethyl, isopropyl, butyl, isobutyl, amyl, and isoamyl acetates are used in ceUulose nitrate and other lacquer-type coatings (see Cellulose, esters). Butyl and hexyl acetates are exceUent solvents for polyurethane coating systems (see Coatings Urethane polymers). Ethyl, isobutyl, amyl, and isoamyl acetates are frequentiy used as components in flavoring (see Flavors and spices), and isopropyl, benzyl, octyl, geranyl, linalyl, and methyl acetates are important additives in perfumes (qv). 

Demand for n-butanol as n-butyl acetate accounts for about 13 percent of domestic consumption of the alcohol. This acetate ester is a general purpose coatings solvent with particular application in nitrocellulose lacquers and moisture cured urethane coatings formulations. n-Butyl acetate is the traditional medium boiling solvent for nitrocellulose lacquers and, as such, is the standard by which other solvents are compared. 

A varnish is a solvent-thinned combination of a drying oil and a hard resin. Also, a varnish is the clear film obtained using a varnish as a coating vehicle. By extension, vehicles used for clear films are called varnishes although the vehicle may be a true varnish, an alkyd resin solution, a urethane-modified oil, or even a lacquer. 

Use Organic synthesis, lacquers, product of hydrotropic salts, alkyd resins, polyamides, polyester adhesives, low-temperature plasticizers, urethane elastomers. 

Use Stabilizer for vinyl resins, lacquers, elastomers catalyst for urethane and silicones. 

Manufacturing ammonium nitrate fertilizer, dyes, drugs, lacquers, cellulose nitrate, nitrate salts, rubber chemicals, and urethanes. Ore flotatation. Metallurgy. Photoengraving. Etching steel. Reprocessing spent nuclear fuel. 

Late in the 1960s, it became apparent that catalyzed lacquers, the hardest, most durable nitrocellulose lacquers commercially available for coating wood, had less resistance to alcohol, cosmetics, and chemicals than did the best quality alkyd-amine compositions or high-pressure melamine overlays. This situation was soon remedied by the development of nitrocellulose-urethane "super lacquers" based on nitrocellulose-isocyanate prepolymers (16). Nitrocellulose as manufactured contains free hydroxyl groups that can provide sites for true cross-linking with an isocyanate-bonded homogeneous coating. Laboratory studies confirmed the theoretical reaction ... 

Thus, a new vista had been created for nitrocellulose, a workhorse in the coatings industry. Tough, resistant nitrocellulose-urethane coatings probably will not be used to replace conventional lacquers. Instead, new opportunities have been created to formulate plastic-like materials that can be spray-applied and air- or force-dried. This new chemical technique has been created to help solve the needs that are constantly recurring in our ever-changing world. 

Nitrocellulose-Urethane Super Lacquers," CSL-202, Hercules, Wilmington, Del., p. 1. 

Vorite. [CasChem] Ifolymerized castor ofl or urethane prepolymers plasticizer, lubricant, penetrant, wetting agent, dispersant, couplbg solvent, adhe promoter for c ul lacquers, inks, adhesives, polish, caulks, leather dressing, hydraulic fluids, rubber conq>dbg., gasket cement... 

The use of accelerator lacquers as a means to cure acrylics has been a very popular method since it allows the priming and storing of parts, the achievement of very rapid cures, and does not require expensive meter-mix-dispense equipment. It should be noted that this cure mechanism is not possible with condensation polymers, such as epoxies and urethanes, since they require full and intimate mixing of both components to achieve complete cures. 

Uses Detoamer, air release agent tor water-based industrial coatings, high-solids coatings, acrylic urethanes, alkyds, epoxies, printing inks, wood lacquers, adhesives, latex detoamer in food-contact paper/pa-perboard food pkg. adhesives... 

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