Grease resistance test for paper and paperboard

This classical method is an expanded and updated version of TAPPI UM 557 “Repellency of Paper and Board to Grease, Oil, and Waxes (Kit Test).”

Commonly known as the kit test, the method describes a procedure for testing the degree of repellency and/or the antiwicking characteristics of paper or paperboard treated with fluorochemical sizing agents (1,2).

Fluorochemical agents may impart both organophobic and hydrophobic characteristics to paper through a reduction in the surface energy of the sheet. This is done by a surface treatment of the fibers without the formation of continuous films.

This test was originally developed to allow papermakers to know when the applied fluorochemical was incorporated into the sheet and the approximate level of resistance. These were accomplished by testing production samples with a series of numbered reagents (varying in surface tension and viscosity or “aggressiveness”) held in bottles in a specially designed kit. The highest numbered solution (the most aggressive) that remained on the surface of the paper without causing failure was reported as the “kit rating” (hence the term “kit test”). This concept forms the basis for the current classical method.

Designed primarily as a surface repellency test for fluorochemical treatments, the use of this test for papers with film-like barriers or those treated with nonfluorochemical agents would have to be evaluated.

A related test is TAPPI T 454 “Turpentine Test for Voids in Glassine and Greaseproof Papers” which is more limited in terms of paper type and may detect a different failure mechanism than this method.