Paint, conventional solvent

The main uses of petroleum naphtha fall into the general areas of solvents (diluents) for paints, etc, dry-cleaning solvents, solvents for cutback asphalt, solvents in mbber industry, and solvents for industrial extraction processes. Turpentine, the older, more conventional solvent for paints, has been almost completely replaced by the cheaper and more abundant petroleum naphtha. 

Conventional Solvent Paint. Based upon a solvent paint of 45J solids content, the 1.0 mil dry film thickness will require a 2.22 mil wet film thickn ss and a solvent content of 68.4 gallons per hour for a 90,000 ft /hr throughput. If one takes an exhaust ratio of 166 ft3 of air per minute, per gallon of solvent per hour... 

Estimates of the Heat Input for the Operation of the Afterburner for the Conventional Solvent Paint. Based upon the calculated exhaust rate of 11,350 cfm of 70 F air, one can estimate the required hourly heat input Q from the relation Q =... 

Chlorinated Poly(Vinyl Chloride). Post-chlorinated PVC combines the advantageous properties of PVC, e.g., good chemical and weather resistance with good solubility in most conventional solvents. Its importance has, however, continually decreased in the paints sector. 

Poly(vinyl ester) dispersions are important binders for indoor (conventional, solvent-free) and outdoor paints, special coatings, and textured finishes. Special types are used for wood paints and for coating paper and cardboard. Poly(vinyl ester) dispersions are also important in the adhesives and textile finishing industries. 

The required application viscosity of waterborne emulsion paints is generally obtained by adding a small volume of water. The evaporation behavior of polymer dispersions is similar to that of conventional, solvent-based paints. 

The changes in quantities shipped from 1995 to 2000 are small, perhaps reflecting a mature industry with slow or no growth. These volumes will reflect changes made in response to regulations. Changes from conventional solvent borne to HSSB will reduce volume shipped, but the dollar value of paint shipped... 

Tests on acrylic/styrene dispersions having varying minimum film forming temperatures demonstrate that when a suitable binder is used, solvent-free paints can be formulated, which exhibit weathering behaviour comparable to that of conventional solvent-based paints. Rutile titanium dioxide pigments are shown to have a greater influence on weathering resistance than the binder. 6 refs. 

Note well that the long, steady trend toward water-based paints continues unabated. In the four principle classes, sixty percent of water-based paints have vehicles which mainly are latexes synthesized from vinyl acetate and several acrylate esters, all derived from petrochemicals such as ethylene. The other 40% are still made mainly from conventional solvent-based alkyds, but there is new interest in transforming these alkyds into water-based alkyds, where sucrose may find new opportunities. 

A new generation of paints has been invented that are water-based rather than the conventional solvent-based ones, thus eliminating the need for handling solvents or having expensive VOC treatment facilities necessary when solvent-based paints are used. Also, the hazards from flammable materials are totally eliminated. Risks involved in the transportation of flammable solvents are also eliminated by this substitution. 

In contrast to the conventional solvent-based paints using toxic biocides, the water-based sol-gel paint does not contain harmful substances and is simply and efficiently applied at room temperature, requiring neither curing nor pretreatment coat for bonding to a variety of substrata, while the painted surfaces are uniform, uncracked, and topographically smooth, which make them viable AF/FR candidates for specialized applications on surfaces involved in optics, sensors, solar panels, and related applications (Figure 34.4). 

Stringent legislations concerning the amount ofVOCs in all paint types have caused many companies to seek alternatives to solvent-borne paint systems, making the move to waterborne systems, the main focus of which is to improve film properties to the level of conventional solvent systems. Hence, a combination of CCTP and emulsion polymerization was explored as a method of creating additives for waterborne paints. ... 

Conventional solvent systems - This includes conventional solvent-based paints as described above. This technology is mature and declining. 

Spraying Thermoplastics solutions such as those based on p.v.c./p.v.a. copolymers may be applied by conventional paint spraying equipment. Because they are thermoplastic they do not require heat to crosslink them, but they may require some heat to evaporate off the solvents. 

---