Class VI — Medical
USP Class VI certified pad print inks for implantable medical devices and internal applications. The highest level of medical certification — meets cytotoxicity, sensitization, and intracutaneous reactivity tests required for in-body use. Five certified products span standard plastics (PLT4) plus TPR and TPU elastomer substrates.
- PLT4 #10 — Yellow (nylon, powder-coated, general medical plastics)
- PLT4 #30 — Blue (nylon, powder-coated, general medical plastics)
- PLT4 #65 — Black (nylon, powder-coated, general medical plastics)
- TPR #980 — Black (thermoplastic rubber substrates)
- TPU #980 — Black (thermoplastic polyurethane substrates)
About USP Class VI certification
USP Class VI is the highest pharmacopeial classification for inks that contact the human body. It is required for any ink that makes internal contact — implants, indwelling catheters, surgical implements, and any device where the printed surface touches tissue or fluid.
Class VI inks pass three biocompatibility tests:
- Cytotoxicity — the ink does not kill cells in tissue culture
- Sensitization — the ink does not provoke an allergic / immune response
- Intracutaneous reactivity — the ink does not irritate tissue in contact
Typical Class VI applications:
- Syringes with measurement graduations
- Catheters with depth and brand markings
- Medical tubing with lot and orientation marks
- Implantable device marking (where ink contact is permitted)
If your application is external-only / topical, see the Class I page for the wider color range.
Need help selecting this ink?
Send us a substrate sample and target color. We will run adhesion testing and confirm the right PLT chemistry.