ASTM D3708 Standard Test Method for Weight of Wax Applied During Curtain Coating Operation
8. Procedure
8.1 Prepare duplicate specimens by running test blanks prepared in 7.1 through the curtain coater in rapid succession. Pass the carrier board through the curtain such that the 450-mm (18-in.) dimension of the carrier board is at right angles to the curtain.
8.2 Place the two corrugated carrier boards with their coated test specimens on a firm work table with the test specimens facing upward. Cut out exact portions of the specimens measuring 100 by 100 mm, to the nearest 0.5 mm. Use a template and cut around the periphery of the template with a razor blade, ensuring that the cut passes cleanly through both layers of folded paper. Each cut specimen consists, therefore, of a pair of 100 by 100-mm sheets, one having a wax surface and the other having no applied wax.
8.3 Determine the weights of the waxed and the unwaxed sheets.
9. Calculation
9.1 For each specimen, record the following data and calculations for the total wax coating:
C = 100 (A - B)
where:
A = weight ofthe waxed sheet (weight ofpaper plus weight of applied wax), g,
B = weight of the unwaxed sheet, g, and
C = applied wax coating, g/m2 = 100 (A - B)
NOTE 4 - To convert from grams per square metre to pounds per 1000 ft2 multiply C x 0.205.
