ORGANIC COMPOSITE COATED STEEL PANEL EXCELLENT IN CORROSION RESISTANCE AGAINST RUST SLOBBING FROM OTHER PLACE UNDER ALKALINE CONDITION

摘要

PURPOSE: To obtain an org. composite coated steel panel excellent in corrosion resistance against rust slobbing from other places under an alkaline condition by providing a chromate treatment layer, a cation selective org. film and an arbitrary org. film on the surface of a galvenized steel panel and specifying the sum thickness of the org. films. ;CONSTITUTION: A chromate treatment layer is provided to the surface of a galvanized steel panel in an amt. of 10-200mg/m² in terms of metal chromium and a cation selective org. film with a thickness of 0.2μm or more is provided thereon as a second layer and an arbitrary org. film with a thickness of 0.2μm or more is further provided thereon as a third layer to obtain an org. composite coated steel panel wherein the sum thickness of the org. films is 2.2μm or less. As a treatment method for forming the chromate layer, any one of electrolytic type, coating type and reaction type treatment methods can be adapted but the coating type treatment method is advantageous because treatment is easiest and addition capacity can be imparted by various additives.;COPYRIGHT: (C)1995,JPO