Fresh price, weigh-scale and short-life labels mostly print direct thermal. The wrong facestock shows up as a light image, wet smear or lift in the cabinet. Three-proof, five-proof and freezer grade are not “higher is better” — they match an environment.
1. Three-proof thermal paper
Water, oil and abrasion resistance. Fits dry, low-moisture ambient distribution at lower cost. Use it on dry shelves with fast turns that never enter a cabinet. Do not treat it as the default for cold chain or spray-down.
2. Five-proof thermal paper
Adds alcohol and plasticizer resistance. Fits wet, spray and light grease — produce misting or tray overwrap. Better water resistance still does not mean long soak, and it is not freezer-grade. Standard five-proof thermal is not a freezer program.
3. Freezer-grade thermal synthetic
Built for cold chain and paired with freezer-grade adhesive. Fits chilled (0–4 °C) and frozen (about −18 °C). The facestock is less brittle and the image layer is more stable. Confirm both apply temperature and service temperature: applying in a freezer is not the same as applying at ambient then entering the cabinet.
4. Selection
| Duty | Recommended construction |
|---|---|
| Dry, low moisture | Three-proof thermal paper |
| Wet, spray, light grease | Five-proof thermal synthetic |
| Chilled or frozen | Freezer-grade thermal synthetic with freezer-grade adhesive |
After selection, proof on the customer’s printer: density, edge sharpness, then wet-rub or cold-chain apply. LabelStar® matches facestock and adhesive to the duty and validates the printer.
