Keruid Instrument YI01 Yellowness Index Meter

I. Industry Applications:

Under environmental factors such as UV exposure, the molecular chains and structures of polymeric materials like resin and plastics undergo changes. These changes manifest on the material surface as yellowing. We typically use the Yellow Index (YI) to quantify the degree of yellowing and employ a Yellowness Meter to measure the extent and trend of this discoloration.

II. Experimental Standards:

The Yellowing Index (YI) quantifies the degree of yellowing in colorless, translucent, or near-white polymeric materials.

Yellowing detection industry standards include HG/T3862, ASTM E313, and ASTM D6290.

3. Measurement Method:

The yellowness index is measured using a Yellowness Index Meter. The specific instrument type depends on the appearance of the polymer material, such as resin or plastic. For irregular samples like particles or powders, rapid testing involves placing the sample directly into a sample cup for immediate measurement. This method is fast but has lower repeatability; therefore, multiple measurements should be taken and averaged.

For sample types such as films, sheets, and liquids, cut to the appropriate size and measure directly on the yellowness index instrument.

The yellowness index helps us monitor and quantify trends in material yellowness. The yellowness index meter records these trends as data and provides a reasonable, effective, and safe solution for yellowness testing.