Meaning and Purpose
5.1 The function of these test methods is to define the percentage of adhesive and retroreflective optical elements or non-retroreflective particles in the composition of thermoplastic pavement markers, as defined in the applicable code for the manufacture of a particular thermoplastic pavement marker. Subsequent samples, due to ashing, can be used later to test for the presence of titanium dioxide, lead chromate and possibly organic pigments.

ASTM D 4797-2022 Chemical and Gravimetric Analysis of White and Yellow Thermoplastic Road Sign Materials Containing Lead Acid and Titanium Dioxide

Scope of
1.1 These test methods cover procedures for gravimetric analysis of adhesives and hydrochloric acid (HCL) insoluble particles in white and yellow thermoplastic pavement markings. HCL insoluble particles may be retroreflective optical devices, such as glass beads or some other type of retroreflective optical devices, or non-retroreflective particles, such as silica sand, or any two or more combinations of these materials.

1.2 This standard does not address the physical separation and separate quantification of each component in the presence of mixtures of two or more HCL insoluble materials. Instead, it requires the user to visually assess the HCL insoluble material (obtained by following this test method) and report the type of material present.

1.3 This standard is not intended to address the measurement of titanium dioxide or lead chromate pigments (after ashing), as detailed in test methods D1394 and D126.

1.4 This standard will attempt to address the interference of organic pigments on adhesive results.

ASTM D 4797-2022 Chemical and Gravimetric Analysis of White and Yellow Thermoplastic Road Sign Materials Containing Lead Acid and Titanium Dioxide

1.5 The analysis process is shown in the following order:

Percentage of adhesive

Reflector optical element or

Percentage of non-regurgitated particles

1.6 Values expressed in SI units shall be regarded as standards. The values given in parentheses are for reference only.

1.7 This standard is not intended to address all safety issues, 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 to determine the applicability of regulatory restrictions prior to use.

1.8 This international Standard has been developed in accordance with the internationally recognized standardization principles established in the Decision on Principles for the Development of International Standards, Guidelines and Recommendations issued by the Committee on Technical Barriers to Trade of the World Trade Organization.