Marking the surface of Fluoropolymers is a challenge. Typically a contact wheel has been used to place information such as manufacturer or specification on the surface. While effective, this technique limits variable information. Gem chemists developed two ink jet inks for these materials. BKG7761 Black and GNG7765 Green are designed for use on Fluoropolymers in continuous manufacturing processes. Codes are applied prior to sintering ovens. Heat exposure is required to complete adhesion to the jacket surface.
The surfaces to code:
Common industrial Fluoropolymers used in industry include PTFE, FEP and ETFE. PTFE is an abbreviation for poly(tetrafluoroethylene). ETFE is an abbreviation for poly(ethylene-co-tetrafluoroethylene). Tefzel™, FLUON™, and Neoflon™ are trade names for ETFE. FEP is an abbreviation for poly(tetrafluoroethylene-co-hexafluoropropylene).
The newly formulated inkjet inks show adhesion that is comparable to the traditional gravure inks. After processing, codes survive MIL-W-227598 adhesion testing. A sewing needle with a diameter of 0.025 inches is pulled back and forth over the code for 60 cycles. The length of the stroke is 3/8 inch. A small weight of 500 grams is attached to the top of the apparatus to hold the needle in place. 125 cycles should be performed. Passing codes remain legible after this test.
Results may vary with manufacturing and surface conditions. Customer testing is required to confirm performance.