【国外标准】 Standard Test Methods for Bleeding of Pigments

4.1 Test Method A determines the amount of color produced when the pigment is in direct contact with a selected solvent such as toluene. It is useful as a rapid, easily conducted test of the general bleeding characteristics of pigments.4.2 Test Method B determines the amount of color migration into a white film applied over a base coat containing the pigment. It may give a more practical evaluation of whether a pigment will meet specific requirements for bleed resistance.4.3 Both Test Method A and Test Method B measure the extent of bleed.1.1 These test methods cover procedures for determining the bleeding characteristics of dry pigments by direct solvent extraction of the pigment and by overstriping a film with a white coating and observing for the color migration from the base coat containing the pigment.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 problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.