When sourcing thermochromic products, you must prioritize the Activation Temperature (Switching Point), which typically ranges from -15°C to 70°C. Ensure the supplier provides Reversible vs. Irreversible options based on your use case. For industrial applications, verify the Particle Size (D50), usually between 1-10 microns, to ensure compatibility with screen printing, injection molding, or coating processes. Additionally, check the Lightfastness rating, as these pigments are sensitive to UV exposure and may require UV stabilizers for outdoor use.