1. Scope
1.1 This specification covers an ambient-cured, twocomponent water-borne epoxy coating that is intended for use as a finish coat in multicoat water-borne epoxy systems for steel.
1.2 Topcoats are categorized according to performance levels (Sections 2.3, 6, and 7).
1.3 Topcoats meeting this specification, when used with an appropriate primer, are suitable for exposures in Environmental Zones 1A (interior, normally dry), 1B (exterior, normally dry), 2A (frequently wet by fresh water), 2B (frequently wet by salt water), and 3C (chemical exposure, alkaline).
1.4 The specified topcoat is intended for application by brush, spray, or roller over primed surfaces prepared in accordance with the manufacturer’s recommendations. It is suitable for use as a water-borne epoxy topcoat in a twocoat system or as an intermediate coat and topcoat in a three-coat system, to be applied in accordance with the manufacturer’s recommendations.
2. Description
2.1 COMPOSITION
2.1.1 The topcoat specified is based on a reactive oxirane (epoxy) functional resin with amine or acid functional curing agents.
2.1.2 The major volatile component by weight is water. Refer to ASTM D 3792 or ASTM D 4017 for determination of the water content of paints.
2.2 VOLATILE ORGANIC COMPOUND (VOC) CONTENT:
Consult applicable government regulations to determine maximum allowable VOC content and the proper VOC test method for a particular application. The supplier should provide VOC information on the coating as supplied (in the container) and as applied (in the field after recommended thinning).
2.3 PERFORMANCE LEVEL: The finish coat shall be classified according to exposure performance achieved as follows, based on testing of primed systems as specified.
Level 1 Accelerated Testing (Section 6)
Level 2 12-Month Exterior Exposure (Section 7.2)
Level 3 36-Month Exterior Exposure (Section 7.3)
2.3.1 If no performance level is specified, Level 2 is assumed.
