Solvent-borne coating

Electrostatic painting is the application of electrostatically charged paint particles to an oppositely charged workpiece followed by thermal fusing of the paint particles to form a cohesive paint film. Both waterborne and solvent-borne coatings can be sprayed electrostatically. 

A solvent-borne coating generally consists of seven major constituents ... 

To achieve low application viscosity at higher solids in solvent-borne coatings it is necessary to have low polymer molecular weight and narrow PDi. 

The dominant position of conventional emulsion polymerisations in the preparation of polymer colloids is unlikely to change. However, studies of new routes for preparation of polymer colloids are essential for growth of the industry and to meet the increasing demand for replacement of solvent-borne coatings. Thus, there is great scope for the development of less conventional routes to polymer colloids and the application of newer methods of polymer synthesis to preparation of polymer colloids will undoubtedly be a fruitful area for research. 

The growing commercial use of polymer colloids whose preparation involves step polymerisations, hybrid systems and/or new routes to dispersion of polymers has not yet spawned an equivalent level of activity in academic studies. The success of the Avecia ex Zeneca Resins) technology for preparation of polyurethane dispersions is a good example of the importance of such developments. There also is the attraction of using conventional solvent-borne coating vehicles e.g., alkyd resins) in aqueous media and hybrid systems... 

The emission factor, EF, for the organic solvent-borne coating in Ib/gal H2O is first calculated ... 

Use Solvent-free water-borne and solvent-borne coatings, contains silicones. 

The catalyst selection for blocked isocyanates depends on the nature of the blocking agent, the desired cure temperature, the polyol structure, and the application. Mono-, di- and trialkyltin compounds are effective catalysts for many blocked isocyanate reactions with hydroxyl compounds. In most solvent-borne coatings, DBTDL is used as a catalyst. 

Liquid solvent-borne coatings, e.g., for automotive topcoats and industrial coatings Permanent PCB coatings (photoresist ink)... 

Conventional solvent-borne coating Easy to apply... 

Uses Antisagging agent, antisettling agent for solvent-borne coatings Properties Tan paste dens. 7.4-7.6 Ib/gal 69-71% solids Use Level 0.3-1%... 

Chem. Descrip. Polyethylene wax (19%), xylene (81%) dispersion Uses Surf, conditioner, mar resist, aid, abrasion resist, aid for coatings, wood furniture coatings, inks, overprint varnishes, solvent-borne coatings, food-contact coatings... 

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