Seamless Polyimide Fuser Belts

For a few years now seamless polyimide belts have been used in toner fusing for desktop printers and multifunctional printers. The most important advantages compared to using traditional steel or aluminum cores are:

significantly shorter times lead to reach run temperatures
major improvements in energy efficiency
weight-saving and lower logistic costs
flexible belts enable higher print speed and resolutions by allowing a wider fusing nip for both b&w and color applications

For these applications KB RollerTech developed a special coating process and produces seamless belts under clean room conditions. Different thermal and electrical properties of these belts can be precisely adjusted by adding special fillers. Today, the following dimensions are possible:

Diameter: 20 - 310 mm
Length: < 700 mm
Wall thickness: 25 - 150 µm

For the subsequent coating with anti-adhesive materials two alternative processes are used:

Spray coatings with fluoro-polymers and subsequent sintering
Coatings with silicone and subsequent fluoro-polymer coatings

With these processes it is possible to produce belts with a concave geometry. The advantage: the print medium is always guided through the device on a defined path, therefore reducing paper wrinkles.

New: metal coatings on polyimide belts

Applying metal coatings (e.g. copper or nickel) on polyimide belts through the use of a special PVD process is a newly developed option. These so-called hybrid belts not only open up the opportunity for inductive heating, but offer also a unique combination of the following properties:

long life due to high abrasion and wear resistance
high mechanical stability
high temperature resistance (temporary: -269°C to +400°C, permanent: up to +230°C)
exceptional resistance to radiation, hydrolysis and chemicals
low weight
flame resistant without using flame protection agents

For more details go to "Materials"