US 7,320,825 B2
Barrier coatings for oil and grease resistance
Patrick Morabito, Matamoras, Pa. (US)
Assigned to International Paper Company, Memphis, Tenn. (US)
Filed on May 27, 2003, as Appl. No. 10/448,068.
Prior Publication US 2004/0241475 A1, Dec. 02, 2004
Int. Cl. B32B 5/16 (2006.01)
U.S. Cl. 428—402  [428/537.5; 428/507; 428/326; 428/328; 428/330; 427/391; 427/395] 27 Claims
 
1. A multi layer composite having oil and grease resistance comprising:
a) a paper or paperboard substrate,
b) a base coat on a surface of said substrate comprising a first polymer selected from the group consisting of film forming natural and synthetic polymers in the substantial absence of a mineral pigment filler, and
c) a top coat on a surface of said base coat, said top coat comprising a continuous polymer phase comprising one or more film forming synthetic polymers having dispersed therein a mixture of at least one platy mineral pigment and at least one non-platy mineral pigment;
Said composite exhibits an oil and grease resistance equal to or less than about 4 as measured by “TAPPI-454 Turpentine Test for Grease Resistance of Paper”, in which turpentine is replaced by Crisco Pure Vegetable Oil run at a temperature of 140° F. for 24 hours at TAPPI conditions.