US 12,227,664 B2
Top coat composition
Carmen Flosbach, Wuppertal (DE); Stephen Istivan, Havertown, PA (US); Zoha al-Badri, West Grove, PA (US); Meagan Douple Goff, Philadelphia, PA (US); and Katharina Dreger, Duesseldorf (DE)
Assigned to AXALTA COATING SYSTEMS IP CO., LLC, Wilmington, DE (US)
Filed by AXALTA COATING SYSTEMS IP CO., LLC, Wilmington, DE (US)
Filed on Aug. 27, 2021, as Appl. No. 17/446,189.
Claims priority of provisional application 63/072,679, filed on Aug. 31, 2020.
Prior Publication US 2022/0064475 A1, Mar. 3, 2022
Int. Cl. C09D 133/08 (2006.01); B05D 1/04 (2006.01); B05D 3/10 (2006.01); C09D 133/12 (2006.01)
CPC C09D 133/08 (2013.01) [B05D 1/04 (2013.01); B05D 3/108 (2013.01); C09D 133/12 (2013.01)] 18 Claims
 
1. A waterborne top coat composition comprising:
30-70 wt. % water;
1-30 wt. % pigment(s); and
10-40 wt. % resin solids;
wherein the resin solids comprise from about 60 to 100 wt. % of binder solids and from 0 to about 40 wt. % of crosslinker solids;
wherein the binder solids comprise from about 5 to about 25 wt. % of an acrylic/(meth)acryl copolymer hybrid binder obtained by free-radical copolymerization of tert-butyl acrylate, n-butylacrylate, and methyl methacrylate to form an acrylic resin, inverting the acrylic resin to a secondary dispersion, and performing an emulsion polymerization process with the secondary dispersion in water and from about 75 to about 95 wt. % of one or more additional binders, the sum of the respective wt. % in each case equaling 100 wt. %,
wherein the (meth)acryl copolymer part of the acrylic/(meth)acryl copolymer hybrid binder is without OH-functionality;
wherein the acrylic/(meth)acryl copolymer hybrid binder comprises about 25 to about 80 wt. % of the acrylic resin, and
wherein the waterborne top coat composition has a total solids content of at least 30 wt. %, based on a total weight of the waterborne top coat composition.