US Patent No. 10,427,978

COATED BUILDING PANELS AND ARTICLES CONTAINING CALCIUM SULFATE HEMIHYDRATE


Patent No. 10,427,978
Issue Date October 01, 2019
Title Coated Building Panels And Articles Containing Calcium Sulfate Hemihydrate
Inventorship Lee K. Yeung, Vernon Hills, IL (US)
Jeffrey F. Grussing, Trevor, WI (US)
Christopher J. Borovka, Grayslake, IL (US)
Assignee UNITED STATES GYPSUM COMPANY, Chicago, IL (US)

Claim of US Patent No. 10,427,978

1. A coated interior panel comprising:a building panel comprising one of the group consisting of gypsum panels, cement panels, panels having both gypsum and cement and mixtures thereof; and
a primer coating on the panel surface obtained by applying to the panel surface a coating having a thickness of about 5 to about 20 mil when said coating is wet, said coating comprising:
10-40% by weight of a latex emulsion binder having a molecular weight greater than 10,000 Daltons;
30-80% by weight calcium sulfate hemihydrate;
less than 8% by weight of a dual set inhibiting agent, wherein the dual set inhibiting agent consists of a first set inhibiting agent and a second set inhibiting agent, and wherein
the first set inhibiting agent is a compound of 0.1% or more by weight selected from the group consisting of tetrasodium pyrophosphate, tetrapotassium pyrophosphate, aminotri(methylene-phosphonic acid), diethylenetriamine penta (methylene phosphonic acid) trisodium salt, hexamethylene diamine tetra(methylene phosphonic acid) and mixtures thereof; and
the second set inhibiting agent is a polymer of 0.05% or more by weight and having a molecular weight from 2,000 Daltons to 6,000 Daltons and selected from the group consisting of a polymer made from a monomer selected from the group consisting of vinyl acrylates, vinyl acetates, vinyl chlorides, ethylenes, styrenes, substituted styrenes and mixtures thereof; and
10-40% by weight water; and
wherein said coating does not comprise a set accelerator.