DETAILED DESCRIPTION OF THE INVENTION AND SPECIFIC EXAMPLES As indicated above, the present invention contemplates the application of an organic, synthetic, polymeric, hydrophobic, thermoplastic water resistant film forming resin containing less than 35% by weight (dry basis) of an infusible pigment or filler, to a paper substrate, and contacting of the resin with an ammonium zirconyl complex either by reason of its being included within the coating composition or by topical application of an aqueous solution thereof to the coated paper.
The paper substrate used herein is desirably precoated with a known barrier precoat composition, such as disclosed in our copending application Ser.
No.
87,241, assigned to assignee of the present invention.
These coating compositions contain clay, styrene-butadiene latex, soybean protein and a melamine-formaldehyde cross linking agent.
The preferred film forming resinous materials for use in accordance the present invention are normally solid, water-insoluble, thermoplastic, organic, addition copolymers or multipolymers of a nonacidic ethylenically unsaturated polymerizable monomer and an ethylenically unsaturated aliphatic carboxylic acid.
The most satisfactory resinous materials contemplated for use herein are addition polymers which are normally solid at room temperature, e.
g.
, 25.
degree.
C.
, thermoplastic, normally insoluble in water and contain a plurality of functional groups reactive with ammonium zirconyl complex, e.
g.
, carboxylic acid groups.
The preferred materials within this group have glass transition temperatures which are generally below about 115.
degree.
C.
, and preferably within the range from 0.
degree.
to 100.
degree.
C.
The film forming resin may be applied as a colloidal dispersion in aqueous medium or as an aqueous latex.
Suitable resinous materials for use in forming an aqueous colloidal dispersion or latex are the random copolymer products or mixtures of one or more polymerizable ethylenically unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, fumeric acid, citraconic acid, and citraconic anhydride, methylhydrogen maleate, and one or more nonacid polymerizable monomers such as ethylene, propylene, butene-1, 1,3-butadiene and other aliphatic olefins, e
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