Device and method fixing and glossing toner images
AssigneeXeikon NV
InventorEtienne Marie De Cock
Life of this patent
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Abstract
A substrate carrying an unfixed toner image is fed through a contact zone which extends continuously from an entrance to an exit (18; 78). The zone is defined by an endless surface such as a first belt and a reaction surface such as a second belt in face-to-face pressure contact therewith. The first belt adjacent the entrance is heated to a temperature sufficient to reduce the viscosity of the toner to less than 50 Pa s. The first belt is forcibly cooled intermediate the entrance and the exit to a temperature below the glass transition point T.sub.g of the toner. Thereby un-fixed toner images can be fixed to the substrate and provided with a desirable level of gloss in one single device, while widening the range of operating conditions without risk of offset occurring.
Claims13
A method of fixing an unfixed toner particle image on a substrate, comprising:
- feeding a substrate carrying an unfixed toner image through a contact zone which extends continuously from an entrance to an exit thereof and is defined by an endless surface and a reaction surface in face-to-face pressure contact with said endless surface, said toner having a glass transition point above room temperature and a viscosity at room temperature of at least 50 Pa s;
- heating said endless surface adjacent said entrance to a temperature above said glass transition point sufficient to reduce said viscosity to less than 50 Pa s;
- and
- forcibly cooling said endless surface intermediate said entrance and said exit to a temperature below said glass transition point.
A device for fixing an unfixed toner particle image on a substrate, comprising:
- an endless surface;
- a reaction surface in face-to-face pressure contact with said endless surface to form a contact zone therebetween, extending continuously from an entrance to an exit;
- means for feeding a substrate carrying an unfixed toner image through said contact zone from said entrance to said exit, said toner having a glass transition point above room temperature and a viscosity at room temperature of at least 50 Pa s;
- heating means for heating said endless surface adjacent said entrance, said heating means being capable of heating said endless surface adjacent said entrance to a temperature sufficient to reduce said viscosity to less than 50 Pa s;
- cooling means for forcibly cooling said endless surface intermediate said entrance and said exit to a temperature below said glass transition point;
- and
- means for applying pressure between said endless surface and said reaction surface intermediate said entrance and exit.
A device for fixing an unfixed toner particle image on a substrate, comprising
- an endless surface,
- a reaction surface in face-to-face pressure contact with said endless surface to form a contact zone therebetween, extending continuously from an entrance to an exit, said toner having a glass transition point above room temperature and a viscosity at room temperature of at least 50 Pa s,
- means for feeding a substrate carrying an unfixed toner image through said contact zone from said entrance to said exit,
- heating means for heating said endless surface adjacent said entrance, said heating means being capable of heating said endless surface adjacent said entrance to a temperature sufficient to reduce said viscosity to less than 50 Pa s,
- cooling means for forcibly cooling said endless surface intermediate said entrance and said exit to a temperature below said glass transition point, and
- second heating means for heating said endless surface adjacent said exit to a temperature above said glass transition point.
Dependencies are inferred from the claim text.