| abstract |
An improved PVOH-based coating solution is provided for application to a polymeric substrate. The coating solution includes poly(vinyl alcohol), a formaldehyde-containing crosslinking agent and a crosslinking-promoting acid catalyst which lowers the pH of the solution to 3.5 or less and, preferably, to 3 or less. The coating solution exhibits improved viscosity stability, particularly with the addition of a second acid catalyst. The coating solution also provides improved crosslinking and oxygen barrier characteristics upon drying. |