| 摘要 |
<p>A low volatile organic content hybrid silica binder, with a total silica content of about 29% to about 42% by weight, suitable for use in the manufacture of zinc-rich primer coating compositions is disclosed. The binder comprises a predominant amount of a silica component derived from the hydrolysis of an organic silicate and a lesser amount of a silica component derived from a silica sol. The solvent component comprises no more than about 75% by weight of an organic solvent having a volatility equal to or greater than the volatility of a C1 to C3 alkyl monohydric alcohol and about 25% by weight or more of a solvent having a lesser volatility than the volatility of a C1 to C3 alkyl monohydric alcohol, with the condition that no more than about 90% by weight of such lesser volatile solvent is a butanol.</p> |
