US 12,460,093 B2
Aqueous electrocoating materials comprising a silane-containing crosslinker
Joerg Ressel, Münster (DE); Thorsten Gelbrich, Münster (DE); Justina Muehlmeyer, Münster (DE); Andrea Hoene, Münster (DE); Andre Brosseit, Münster (DE); Nina Wissmann, Münster (DE); Petra Toboll, Münster (DE); Susanne Hemker, Münster (DE); Silke Przybilla, Münster (DE); Martin Geuting, Münster (DE); Janine Juettemeyer, Münster (DE); Dirk Benning, Münster (DE); and Hildegund Diekmann, Münster (DE)
Assigned to BASF COATINGS GMBH, Muenster (DE)
Appl. No. 17/793,971
Filed by BASF COATINGS GMBH, Münster (DE)
PCT Filed Jan. 11, 2021, PCT No. PCT/EP2021/050338
§ 371(c)(1), (2) Date Jul. 20, 2022,
PCT Pub. No. WO2021/148261, PCT Pub. Date Jul. 29, 2021.
Claims priority of application No. 20153528 (EP), filed on Jan. 24, 2020.
Prior Publication US 2023/0091880 A1, Mar. 23, 2023
Int. Cl. C09D 7/61 (2018.01); C08G 18/22 (2006.01); C08G 18/28 (2006.01); C08G 18/76 (2006.01); C08G 18/79 (2006.01); C08G 18/80 (2006.01); C09D 5/44 (2006.01); C09D 7/63 (2018.01); C09D 175/04 (2006.01); C25D 13/22 (2006.01)
CPC C09D 5/4465 (2013.01) [C08G 18/227 (2013.01); C08G 18/283 (2013.01); C08G 18/289 (2013.01); C08G 18/7671 (2013.01); C08G 18/794 (2013.01); C08G 18/8019 (2013.01); C08G 18/8029 (2013.01); C08G 18/8064 (2013.01); C08G 18/808 (2013.01); C08G 18/809 (2013.01); C09D 7/61 (2018.01); C09D 7/63 (2018.01); C09D 175/04 (2013.01); C25D 13/22 (2013.01)] 20 Claims
 
1. An aqueous electrocoating material (ECM), comprising—based on a total weight of the electrocoating material—
(a) at least one binder (B) containing cationic or anionic groups and reactive functional groups which are able to undergo crosslinking reactions with complementary reactive functional groups present in a crosslinking agent (CA),
(b) at least one crosslinking agent (CA) containing fully blocked isocyanate groups and at least one silane group;
(c) at least 100 ppm bismuth;
(d) at most 300 ppm of dissolved lithium; and
(e) optionally at least one additive (AD);
wherein
the at least one crosslinking agent (CA) is prepared by
(i) reacting 0.01 to 5 mol-% of a total amount of free isocyanate groups present in at least one parent structure P with at least one compound of general formula (I)
HN[X-SiR1a(OR2)3-a]n[X′-SiR1b(OR2)3-b]m[R3]2-(m+n)  (I)
wherein
X, X′ represent, independently from each other, linear and/or branched alkylene or cycloalkylene radicals having 1 to 20 carbon atoms;
R1 represents an alkyl, cycloalkyl, aryl, or aralkyl group, it being possible for the carbon chain to be interrupted by nonadjacent oxygen, sulfur, or NRa groups, where Ra is alkyl, cycloalkyl, aryl, or aralkyl;
R2 represents hydrogen, an alkyl, or a cycloalkyl group, it being possible for the carbon chain to be interrupted by nonadjacent oxygen, sulfur or NRa groups, where Ra is alkyl, cycloalkyl, aryl, or aralkyl;
R3 represents a linear and/or branched alkylene or cycloalkylene radicals having 1 to 20 carbon atoms;
n,m are, independently from each other, 1 or that m is 1 and n is 0; and
a,b are, independently from each other 0 to 2;
(ii) reacting the free isocyanate groups of the parent structure P remaining after step (i) with at least one blocking agent BA to obtain the crosslinking agent (CA) comprising fully blocked isocyanate and silane groups; and
(iii) optionally diluting the crosslinking agent (CA) obtained in step (ii) with at least one solvent.