Self-stratifying coatings
AssigneeThe Sherwin-Williams Company
InventorsPeter J. Mackulin, Randolph B. Krafcik, Benjamin M. Borns, Jyotindra K. Doshi, Wendy Zhao
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Abstract
The present invention relates to coating compositions formed by combining two latex resins: a base latex resin and a stratifying latex resin. The stratifying latex resin comprises at least one “driver” to promote migration of the stratifying latex to the surface of the coating during curing or drying. Drivers may be selected from one or more of fluorine containing monomers incorporated into the stratifying latex, long chain acrylate monomers, such as lauryl methacrylate, wax, small particle size, or relatively low Tg.
Claims15
An aqueous coating composition comprising:
- (1) a base latex resin;
- and
- (2) a stratifying latex resin having latent crosslinking functionality, the stratifying latex comprising the polymerization reaction product of at least one or more copolymerizable monoethylenically unsaturated monomers, wherein the monoethylenically unsaturated monomers comprise (a) at least one fluorine containing monomer and (b) at least one monomer having latent crosslinking functionality, wherein the stratifying latex resin is a two-stage polymer formed by sequentially polymerizing a first group of monomers to form a core and a second group of monomers to form a shell, and wherein the core has a Tg from about −20° C. to about 10° C. and comprises the polymerization reaction product of a fluorine containing monomer, a monomer having latent crosslinking functionality;
- and a long chain acrylate monomer having an alkyl length of at least 12, and wherein the shell has a Tg from about 35° C. to about 100° C. and comprises the polymerization reaction product of one or more copolymerizable monoethylenically unsaturated monomers excluding fluorine containing monomers.
Dependencies are inferred from the claim text.