MULTIPLE COMPONENT MATERIALS HAVING A COLOR-CHANGING COMPOSITION

摘要

The present invention relates to a multiple-component material including a substrate and a printed layer on the substrate. The printed layer includes a color-changing composition to indicate a change in condition, such as a change in pH. The color-changing composition includes a matrix-forming component, a colorant, a surfactant and a pH adjuster. The pH adjuster includes a low molecular weight organic acid and a high molecular weight organic acid.