PKP values indicate high aromatic or high naphthenic content, or both, which contributes to high relative solvency of the oil.

1.1 This test method covers a procedure for determining the relative solvency of petroleum oils used in ink formulations by a pentaerythritol ester of resin acids (PKP) titration.

1.2 This test method is applicable to petroleum oils that have an initial boiling point over 90^oC and a dry point under 500^oC as determined by Method D86.

1.3 This test method, along with viscosity measurements as determined by Test Method D445, is used to ensure the compositional consistency of petroleum oils. It can also differentiate between hydrotreated and non-hydrotreated oils that have the same viscosity.

1.4 This test method includes the use of a U.S. Occupational Safety and Health Administration (OSHA)-designated flammable chemical, pentane. Consult the suppliers' material safety data sheet for specific hazard information and guidance relative to use.

1.5 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. Specific hazard statements are given in 1.3.