Aqueous inpress primer sealer for hardboard manufacturing

Claim 1

In a process for manufacturing prefinished hardboard products by hot pressing fibrous materials in a hot press mold, the improvement comprising: applying an aqueous dispersed primer-sealer composition to a surface layer of overlay paper or surface mat to provide a resin impregnated surface layer, where the primer-sealer composition comprises on a weight basis between about 15% and 40% methoxylated melamine resin, between about 30% and 60% acrylic emulsion copolymer having an Acid N. above about 15, between about 5% and 25% vinyl acetate-vinyl versatate copolymer latex containing copolymerized monomers of 40% to 90% vinyl acetate and 10% to 60% vinyl versatate, between about 3% and 15% emulsified fatty acid having 12 to 22 carbon atoms and an Iodine No. above 100, and between about 3% and 15% polyvinyl alcohols, where the primer-sealer composition contains pigment and the pigment-volume-content (PVC) is above about 30%; drying the resin impregnated surface layer to produce a dried surface layer; storing the dried surface layer in layered arrangements without sticking between layers; removing from storage and laminating the dried surface layer to the surface of a fiberboard composite under pressure and heat to form a prefinished hardboard product having a prefinished surface free of sticking in the hot press.