Water-borne coating

To further reduce the emission of solvents from coatings, water-borne two-component coatings cross-linked with isocyanates are being developed. The challenge in formulating these systems is the selection of a catalyst that is hydrolytically stable and catalyzes only the hydroxyl reaction and not the water reaction. Di-n-butyltin carboxylates i or phenoxides hydrolyze to the oxide in water. Di-n-butyltin bis(2,3-dihydroxypropylmercaptide) is reported to be stable in water and has been used in two-component water-borne coatings. ... 

Chem. Descrip. Channel-type carbon black CAS 1333-86-4 EINECS/ELINCS 215-609-9 Uses Filler, pigment for coatings, water-borne primers, printing inks, plastics... 

It was prophesied in the 1960s that oil-based paints would disappear from the market in about 20 years in favour of petrochemical-based products. This has not happened, and the main protective paints are still based on fatty oils. In fact, following the oil crisis, the trend has been back to raw materials from renewable resources. None of the new technologies such as the use of powder coatings, water-borne paints, or radiation-curing paints, which would not have been based on oils, have proved as versatile as expected. 

L. L. Xing, J. E. Glass, andR. H. Fernando, "Technology for Water-Borne Coatings," iaj. E. Glass, ed., C3 Symposium, Series 663, American Chemical Society, Washiagton, D.C., 1997, Chapt. 15. 

P. A. CaUais, V. R. Kamath, and M. G. Moskal, Proc. Water-Borne, Higher-Solids, Powder Coat. Symp. 19, 156 (1992). 

Fig. 4. Dose response for blood glucose measurement using a dry chemistry system having a water-borne, tough coating film. The numbers represent...

Excellent correlation was found when results at 660 nm and 749 nm were compared using a reference hexokinase glucose method (27). The dose response was excellent up to 300 mg/dL glucose. In general, water-borne coatings do not lend themselves to ranging by antioxidants (qv). 

S. Didikov and co-workers, Water-Borne, Higher-Solids, andTowder Coatings Symposium, University of Southern Mississippi and Southern Society for... 

Water-borne polyurethane coatings are formulated by incorporating ionic groups into the polymer backbone. These ionomers are dispersed in water through neutrali2ation. The experimental 1,12-dodecane diisocyanate (C12DI Du Pont) is especially well suited for the formation of water-borne polyurethanes because of its hydrophobicity (39). Cationomers are formed from IPDI, /V-methyIdiethan olamine, and poly(tetramethylene adipate diol)... 

Water-borne adhesives are preferred because of restrictions on the use of solvents. Low viscosity prepolymers are emulsified in water, followed by chain extension with water-soluble glycols or diamines. As cross-linker PMDI can be used, which has a shelf life of 5 to 6 h in water. Water-borne polyurethane coatings are used for vacuum forming of PVC sheeting to ABS shells in automotive interior door panels, for the lamination of ABS/PVC film to treated polypropylene foam for use in automotive instmment panels, as metal primers for steering wheels, in flexible packaging lamination, as shoe sole adhesive, and as tie coats for polyurethane-coated fabrics. PMDI is also used as a binder for reconstituted wood products and as a foundry core binder. 

The principal markets for neopentyl glycol (NPG), the hydrogenated, crossed aldol condensation product of isobutyraldehyde and formaldehyde, are in water-borne and alkyd-surface coatings. 

D. C. Busby and co-workers. Supercritical Fluid Spray Application Technology A Pollution Prevention Technologyfor the Futures PP- 218—239 Proceedings of the 17th Water-Borne and High-Solid Coating Symposiums New Orleans, La., 1990. 

Such polyurethanes have excellent hydrolytic stability compared to water-reducible polyesters and superior abrasion resistance. In view of the importance of developing low solvent emission coatings, considerable effort is being devoted to new types of water-borne urethane resins (62,63). 

D. E. Eiori and R. W. Dexter, Proceedings of the Water-Borne Higher-Solids Coatings Symposium New Orleans, 1986, p. 186. 

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