ASTM D6657-16(2021)

1.1 This test method covers the determination of the pH of all types of Wet Blue and Wet White.

1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

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, 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.

4.1 This test method is designed to measure the pH of a distilled-water extract of Wet Blue and Wet White. This is considered to be a measure of the acidity or alkalinity of the Wet Blue or Wet White. Excessive acidity or alkalinity may have a deleterious effect on the aging characteristics of Wet Blue and Wet White and the leather made from it.

4.2 This test method is suitable for development, control, and service evaluation of wet blue.