	US 12,473,654 B2
	Use of silicon dioxide for improving the cathodic anticorrosion effect of ground coats
Markus Hallack, Schermbeck (DE); Berend-Jan de Gans, Muelheim an der Ruhr (DE); Florian Düllmann, Hagen (DE); and Sascha Herrwerth, Freigericht (DE)
Assigned to Evonik Operations GmbH, Essen (DE)
Filed by Evonik Operations GmbH, Essen (DE)
Filed on Aug. 11, 2021, as Appl. No. 17/399,171.
Claims priority of application No. 20190611 (EP), filed on Aug. 12, 2020.
Prior Publication US 2022/0049362 A1, Feb. 17, 2022
Int. Cl. C23F 11/18 (2006.01); C08K 3/08 (2006.01); C08K 3/36 (2006.01); C08K 9/06 (2006.01); C09D 5/08 (2006.01); C09D 5/10 (2006.01); C09D 7/61 (2018.01); C09D 7/62 (2018.01); C09D 163/00 (2006.01); C09G 1/00 (2006.01)

CPC C23F 11/18 (2013.01) [C08K 3/36 (2013.01); C08K 9/06 (2013.01); C09D 5/084 (2013.01); C09D 5/10 (2013.01); C09D 5/106 (2013.01); C09D 7/61 (2018.01); C09D 7/62 (2018.01); C09D 163/00 (2013.01); C09G 1/00 (2013.01); C08K 2003/0893 (2013.01); C08K 2201/006 (2013.01)]

15 Claims

1. A method of improving a cathodic anticorrosion effect of a functional coating based on epoxy-functional polymers and at least one metal particle, the method comprising

incorporating silicon dioxide into the functional coating, wherein the silicon dioxide consists of pyrogenic silicon dioxide,

wherein said pyrogenic silicon dioxide particles have a tamped density of 10-100 g/L, a numerical average particle size of 50 to 100 nm, and a BET surface area of 20 m²/g-1000 m²/g, determined according to DIN 9277:2014 by nitrogen adsorption in accordance with the Brunauer-Emmett-Teller method, and

the functional coating comprises at least one curing agent selected from the group consisting of aliphatic, cycloaliphatic, and aromatic amines; aliphatic, cycloaliphatic, and aromatic polyamides; and amidoamines based thereon.