High-solids solvent-borne coatings

With the move towards high solids solvent borne coatings, hydroxy acrylic coatings have more to offer, but there are still two main disadvantages ... 

SB = solvent-borne, WB = waterborne, HS = high solid, PC = powder coating. SF=solvent-free... 

Emulsions of these resins with relatively high solids content can be prepared while the corresponding solvent cuts have viscosities too high for use in coatings. For example, at 40% solids in Cellosolve acetate, ARALDITE 488 has a viscosity of 6000 cP. while the water-borne emulsion at the same solids level is only 1000 cP. For most methods of application the solids content of the solvent cut would have to be dropped below 40% to give a workable viscosity and this would exclude the resin from some important end uses such as can end and 3-piece can body coatings. The resin in its emulsified form, however, has the proper solids/viscosity relationship for this particular end use. 

Rule 66 (later called Rule 442 of the South Coast Air Quality Management District) also limited oven emissions from baked coatings. Incineration, absorption, or recovery of volatiles is needed to meet this restriction. In further regulations, use of high-solids, low-solvent, water-borne, and other types of coatings with low-volatile emissions was encouraged. The evolution of various air pollution regulations has been summarized (74, 75). 

Uses Crosslinking agent for solvent-borne and high solids coatings incl. automotive, plastic, exterior container, paper, wood, and general metal coatings... 

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