Meaning
Specialty printing materials utilize a heat-sensitive coating to create images without the need for ink or ribbons. Direct thermal paper contains micro-encapsulated leuco dyes and co-reactants that change color when exposed to the heated pins of a thermal printhead. This technology is widely used for shipping labels, point-of-sale receipts and mobile ticket printing.
It is not suitable for documents that must be archived or exposed to high heat.
Thermal Sensitivity
Industrial printers require specific paper grades that match their operating speeds and heat outputs. The sensitivity of the paper determines how quickly the chemical reaction occurs and how dark the resulting print will be. High-sensitivity paper allows for faster printing speeds but is more prone to accidental activation from ambient heat or friction during handling.
Choosing the correct sensitivity is a balance between speed and label resistance to premature discoloration.
Print Durability
Heat, light and chemical exposure can degrade the printed image over time. In distribution environments, shipping labels are often exposed to sunlight, moisture or plasticizers from stretch wrap, which can cause the print to fade or turn completely black. This fading can render barcodes unreadable by scanners.
Substrate Grade
Base material choice affects the strength and longevity of the printed label. Higher-grade papers use synthetic films or protective topcoats to resist tearing, water absorption and chemical attack. This selection is determined by the specific requirements of the distribution channel.
