ASTM D6131-97(2004)

This test method allows the user to make a quick determination of the blueness or yellowness of the tint undertone of titanium dioxide pigments, versus a reference pigment agreed upon by the parties to the test. This is an important measure of tone, since it gives both a measure of effective particle size, and quick approximation of the blue/yellow undertone that can be expected when a coating containing the titanium dioxide is tinted.

Such matters as the vehicle for preparing the dispersions, and the black for tinting have been suggested. However, changes in the components may be made by agreement between the buyer and the seller.

The results obtained with a mechanical muller do not necessarily correlate directly with a practice where different dispersion conditions exist. However, dispersion with a mechanical muller is a quick and inexpensive way of evaluating the undertone of a titanium dioxide pigment.

1.1 This test method is intended to be used to determine the tint undertone (blue or yellow) of titanium dioxide pigments. This relates to the effective particle size of the pigment. It is based upon tinting with a black iron oxide, but other blacks may be used if found suitable.

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 does not purport to address all of the safety concerns, if any, 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.