Organosol coatings

Vinyl organosol coatings, which incorporate a high molecular weight thermoplastic PVC organosol dispersion resin, are extremely flexible. Soluble thermosetting resins, including epoxy, phenoHc, and polyesters, are added to enhance the film s product resistance and adhesion. 

Two-piece food cans may be made by a draw-redraw process, in which lacquer is first applied to and cured on sheet. Blanks are then cut from the sheet and the can is drawn from the blank in two or three stages. The lacquer deforms with the drawing process and lubricates the draw. It then becomes the interior protective coating. Although epoxy-phenolic solvent-borne lacquers are used, even better drawing properties are obtained from organosols. These are dispersions of colloidal polyvinyl chloride powder in solutions of other mixed resins in solvent, e.g. chosen from epoxy, polyester, vinyl and phenolic. 

Corrosion has been encountered infrequently to date and has been a surface type, as opposed to pitting corrosion that can result in perforations. Entrapped air in the beverage or in the cans headspace increases the corrosive action of the product according to Koehler et at (21). As with beer and other canned foods, aluminum ends provide electrochemical protection when combined with tinplate or tin-free-steel can bodies. The level of iron pickup is reduced while the amount of aluminum dissolved in soft drinks increases without detrimental effect. Aluminum containers with vinyl epoxy and vinyl organosol coatings are compatible with carbonated soft drinks. 

BPF isomers (Novolac) may arise from their application in the manufacture of Novolac glycidyl ethers (NOGE), which serve as scavengers for hydrogen chloride in PVC organosol coatings. 

An organosol is the same mixture as described above, with the addition of solvent to reduce viscosity. These find their major applications in coatings. The solvent is evaporated before fusion of the film. Various pigments, colorants, stabilizers and fillers may be added, depending on the desired properties. Emulsion polymerization resins are generally employed because of their fast fusion rates. Coarser particle sized PVC resins would require extended time at the elevated temperature. 

Organosols find their major application in coatings, which may be applied by spray, dip, knife, roller, etc. Typical products are coated aluminum siding, fabrics, paper, industrial coatings, etc. 

For plastisol/organosol technology, high-molecular-weight PVC powder is slurried in liquid plasticizer, and poured, dip- or spread-coated onto metal, fabric, or paper to produce dishwasher racks, upholstery, and wallpaper, respectively. 

Organosol Coatings. The low viscosity of organosol formulations permits coatings under 10 mils thick, particularly for chemical resistance. 

Different methods of coating are used to meet different coated product requirements (Table 10.1). The coating materials are in different forms ranging from liquids to solids. They include emulsion, latex, dispersion, lacquer, powdered plastic composition, plastisol, organosol, rubber composition, hot-melt, reacting TS compound, etc. The product could be plastic film, paper, paperboard, woven fabric, plywood, nonwoven fabric, steel sheet, aluminum foil, irregular flat or shaped products, 260... 

Flame retarding plasticizer used in cellulose, polyester and polyurethane. Mainly used in the manufacture of electrical (wire and cable) and automotive plastic parts. May also be used for die preparation of vinyl sheets, fabric coating, plastisols and organosols, adhesives, vinyl packing materials, and conveyor belts. 

Use Film and sheeting flooring coated fabrics wire, cable and other extrusions organosols plasti-sols and plastigels lacquers and rubbers. 

Use A thixotrope for PVC plastisols, organosol, and high- solids solvent-based paints 2064 corrosion inhibitor for latex paint and other water-based coatings 2085B rust-preventative coatings. 

Because water is the fluid component, very low viscosities at relatively high solids (50%) are attainable. Latexes are usually cheaper than solution vinyls but similar in cost to dispersion resins. As with organosols and solution vinyls, coating thickness is limited due to the evaporation of the fluid component. Note that more heat is usually required to remove water than organic solvents, and corrosion of equipment must be considered. 

If an organosol is used, lower plasticizer loadings are possible, but they will limit the thickness of the applied coating. At the same time the volatile solvents force one to select a lower initial preheat temperature of the object to be coated. 

Dokhem. [Dolphin Paint Qiem.] Adhesives, coatings, dispersions, organosols, palms, primers, putty. 

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