Composition and process for zinc phosphate conversion coating
AssigneeHenkel Corporation
InventorsHitoshi Ishii, Yasuhiko Nagashima
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Abstract
A zinc phosphate-type conversion film having microfine-sized crystals is formed on metal surfaces using a conversion treatment bath that contains zinc ions and phosphate ions along with 50 to 1500 ppm of an organoperoxide conversion accelerator, and optionally surfactant. Surface-conditioning treatments can be omitted from this method. The presence of the surfactant makes possible simultaneous execution of surface cleaning and conversion treatment
Claims20
A liquid zinc phosphate conversion coating bath composition comprising water, zinc ions, phosphate ions, and from 50 to 1500 ppm of an organoperoxide conversion accelerator selected from the group consisting of ethyl hydroperoxide, isopropyl hydroperoxide, tert-butyl hydroperoxide, tert-hexyl hydroperoxide, diethyl peroxide, di-tert-butyl peroxide, acetylacetone peroxide, cumene hydroperoxide, tert-butylperoxymaleic acid, monoperphthalic acid, and persuccinic acid.
A bath composition according to claim, wherein nitrogenous compounds are present, if at all, only in an amount having a stoichiometric equivalent as nitrogen of not more than 200 ppm.
Dependencies are inferred from the claim text.