US 4,792,464 AGranted

Corrosion coating composition

OwnerIrvin W. Martensoninventor

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Abstract

There is disclosed a water-base coating composition and method for its use that forms a readily strippable protective film on metal surfaces. The composition includes a film former ingredient which is a terpolymer of polyvinyl butyral, polyvinyl alcohol and polyvinyl acetate. The water-base coating composition also contains a fugitive corrosion inhibitor, i.e., a corrosion inhibitor having a sufficient vapor pressure to impart corrosion resistance to surfaces coated with the film former composition. Suitable corrosion inhibitors are aromatic triazoles such as benzotriazole. A leveling agent such as morpholine is used to prevent the film from pulling from the edges during drying. Morpholine is particularly advantageous as it extends the working time when coating objects, and prevents the dispersion from clogging nozzles of spraying equipment. Morpholine also contributes to the corrosion inhibition of the coating.

Claims11

Dependent claims

The method of temporarily protecting metal surfaces against corrosion which comprises:

a. coating the surface of the metal surface with an anti-corrosion coating composition consisting essentially of:
(1) an aqueous film former comprising 40 to 60 weight percent solids in water with the solids consisting of a terpolymer of from 75 to 90 percent of polyvinyl butyral, from 9 to 25 percent polyvinyl alcohol and from 0.1 to 5 percent polyvinyl acetate;
(2) a sufficient quantity of a hydroxyalkyl cellulose ester in a sufficient quantity to impart thixotropic properties to said coating composition;
(3) an corrosion inhibitor mixture comprising from 0.1 to 2 weight percent of an inhibitor selected from the class consisting of aromatic triazoles, monoethanolamine benzoate and 2-ethyl,1-(N,N-dodecyl hydroxyethyl)amine ethylimadazoline dispersed in a plasticizer for said polyvinyl butyral resin;
and
(4) from 0.5 to 2 weight percent morpholine;
b. exposing the coated metal object to a corrosive environment;
and
c. removing the coating metal object from the corrosive environment and peeling the coating from the metal to expose a metal object free of corrosion.

6 more elements

Dependencies are inferred from the claim text.

Facts

Application: 07/056,378Filed 1 Jun 1987
Granted: 20 Dec 1988
Term ends: Not estimatedThe source records don’t support an estimate.

Classification9 codes

C09D 5/20
Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced ; Filling pastes: for…
B05D 1/325
Removable films used as masks: masking layer made of peelable film
B05D 7/14
Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying…
C08K 5/35
Heterocyclic compounds having nitrogen in the ring: having also oxygen in the ring