Froth coating of paper products and process for forming same
AssigneeReichhold Chemicals, Inc.
InventorDavid S. Heller
Life of this patent
Estimating the term…
Abstract
A froth coated paper substrate in which the froth coating may be densified by compression when applied as a frothed resinous emulsion to improve opacity and ink-holdout of the substrate, or applied as a frothed surface size when the coating is a frothed admixture of a resin emulsion and a starch solution, or a frothed starch solution.
Claims27
A process for producing a smooth coated paper product having improved opacity and ink hold-out characteristics comprising:
- (a) applying at least one coating to the surface of a paper substrate of a frothed emulsion containing a plurality of very fine cells formed from a curable elastomeric resin emulsion having at least 10 parts by weight of filler solids based on 100 parts by weight of elastomeric resin solids;
- (b) spreading said frothed elastomeric resin emulsion over the surface of a paper substrated to produce a substantially uniform, thin frothed coating;
- (c) partially curing said applied thin frothed coating;
- (d) passing said partially cured froth coated paper substrate through a set of calendar rolls to compress said frothed coating to reduce its thickness by about 80 to about 99 percent to form a thin, densified smooth layer, the said layer being from about 2 to about 6 mils in thickness;
- and
- (e) finally curing said densified frothed coating to form a smooth continuous coating intimately bonded to the surface of the paper product.
A smooth coated paper substrate having a thin paper base and at least one thin densified adhesive coating formed from a thin frothed layer of a curable resin emulsion containing at least 10 parts by weight of filler solids based on 100 parts by weight of elastomeric resin solids, said densified adhesive coating formed by compression of a partially cured frothed layer to a thickness of from about 2 to about 6 mils and a reduction in thickness of from about 80 to about 99 percent to form on the surface of the thin paper base a smooth continuous thin coating, followed by a final curing of the coating.
A process for producing an improved smooth surface sizing for paper products comprising:
- (a) applying at least one coating to the surface of a paper substrate of a frothed composition containing a solution of starch solids and filler solids, said frothed composition containing a plurality of very fine cells;
- (b) spreading said frothed composition over the surface of a paper substrate to produce a substantially uniform smooth thin frothed size coating;
- and
- (c) curing said applied thin frothed coating.
Dependencies are inferred from the claim text.