WATER-BASED ZINC-RICH PRE-CONSTRUCTION PRIMER

摘要

A water-based, two-part primer for metal substrates includes at least a first and second part, combined in a ratio of about 1:1. The first part of the primer may be substantially free of volatile organic compounds and include a colloidal silica present in the amount of about 20 weight percent to about 80 weight percent, based on the total weight of the first part; a silane coupling agent selected from the group consisting of epoxysilanes, mercaptosilanes, and modified silanes having a functional group active to an epoxy group, the silane coupling agent present in the amount of about 0.05 weight percent to about 15 weight percent based on the weight of the first part; and a cellulose ether in the amount of about 0.1 weight percent to about 2 weight percent. The second part may include from about 50% by weight zinc powder. The primer may be conventionally sprayable for use in large ship-building operations.

主权项

1. A two-part primer for metal substrates, wherein the two-part primer is water-based and comprises:
a. a first part, wherein the first part comprises:
i. a colloidal silica present in the amount of about 20 weight percent to about 80 weight percent, based on the total weight of the first part;ii. a silane coupling agent selected from the group consisting of epoxysilanes, mercaptosilanes, and modified silanes having a functional group active to an epoxy group, the silane coupling agent present in the amount of about 0.05 weight percent to about 15 weight percent based on the weight of the first part; andiii. a cellulose either in the amount of about 0.1 weight percent to about 2 weight percent; and b. a second part comprising at least 50% zinc powder; wherein the first part and the second part are present in the two-part water based primer in a ratio of about 1:1.