Sheet in FEP GB 1500x1500x0.8 mm natural

A Sheet in FEP GB is a thin fluoropolymer film where one side has been surface treated by etching or a similar process that removes the natural release character of the surface layer. The result is a side that can be bonded, laminated or coated with ordinary industrial adhesives, while the opposite side keeps the smooth, chemical resistant FEP surface.

FEP is a meltable fluoropolymer related to PTFE. The material has very good resistance to acids, bases, solvents and most industrial chemicals. It takes continuous work at temperatures well above a hundred degrees and is barely affected by low temperatures. The surface is hydrophobic, friction is low and the material is dielectric, which makes FEP useful as an electrical insulator too.

That release character is at the same time the property that makes FEP hard to join in the traditional way. Ordinary adhesives get no grip on the glossy surface because there is no chemical or mechanical structure for the adhesive to hook into. The GB treatment solves that by changing the surface on one side so it becomes polar enough for adhesives, primers and pressure sensitive coatings to stick. The glossy other side is left untouched and works like ordinary FEP.

The sheet is used where you need to combine the FEP surface with a bonded fastening. Common cases are release films that are glued to a metal or plastic carrier and then turn the release side toward the product flow, release layers against press tools where the back is bonded to a carrier layer, linings against chemical baths where the film is glued to an underlying support, and composite and laminate structures where FEP works as a corrosion barrier.

The GB side should face the adhesive or the laminate. The glossy side faces the medium, the process flow or the surface where the release character and chemical resistance of FEP are meant to do their work. When bonding, we recommend cleaning grease and dust off the GB surface right before you glue so the contact film is clean.

The material can be welded with FEP Welding Rod if needed, although the welding should then be done against the glossy side, since that is where the melt forms a homogeneous joint with the base material. For cutting, a sharp knife or a punch tool is enough, and thermoforming is possible within the normal temperature window for FEP.

The sheet is supplied in thin gauges and in formats matched to the manufacturer standard.

Do you need help deciding whether GB is the right surface for your bonding, or whether ordinary FEP is enough? Get in touch.

In the 1500x1500x0.8 mm format the sheet is thin enough to follow rounded substrates. The glass fiber on the back, which is what GB stands for, gives it grip when lining.