Wax coatings are applied to corrugated board to provide a barrier against moisture or other penetrants or to provide improved appearance or abrasion resistance. These functional properties are influenced by the amount of wax present on the surface.

During curtain coating operations, major portions of the wax will congeal on the surface, while a minor portion will penetrate and become embedded in the fibers of the facing. This method measures the total weight of wax applied to the board. The amount actually remaining on the surface of the corrugated board can be determined by Test Method D 3521.

The uniformity of application of wax film across the width of the curtain coater may also be determined using this technique by passing test combinations (blanks) under the curtain at various locations, that is, left side, center, right side.

1.1 This test method covers the determination of the weight of hot melt coating applied to corrugated board by curtain coating. It is intended to be used for routine process control in the plant.

Note 1— Related methods for determining the weight of wax coating include the following: Test Method D 3521; Test Method D 3522, and Test Method D 3344.

1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.

1.3 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety problems associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.