1. Field of the Invention
The present invention generally relates to ink jet printheads for solid ink jet imaging apparatus, and more particularly to ink jet printheads that consume less energy during ink jetting operation.
2. Description of the Related Art
Consumer ink jet printers typically use water-based inks with a low concentration of pigment or dye. When these water-based inks are jetted on a print medium, the water evaporates or gets absorbed by the print medium. However, with respect to a solid ink or phase change printer, solid blocks of colored material are melted and jetted in molten form. These molten inks have the consistency of crayons or candle wax and, when transferred on to the print medium, solidify to form a printed image. The solid ink printer produces vivid colors and crisp lines because the ink stands on the surface of the paper instead of penetrating as with water-based inks.
One such example of a solid ink printer 10 is shown in FIG. 1. During an imaging operation, blocks of solid ink 12 are disposed within an ink loader 14. The ink loader 14 has a retaining plate 16 that retains the blocks of solid ink 12. Further, ink loader 14 also has a heating plate 18 disposed therein to make contact with the blocks of solid ink 12 within the ink loader 14. The heating plate 18 melts and transforms the blocks of solid ink 12 into molten form 20. The molten ink 20 is then injected into the printhead assembly 22, which in turn gets jetted on to an imaging drum 24 present within the solid ink printer 10. Accordingly, the molten ink 20 gets transferred on to the print medium 26 to form an image. However, there are considerable drawbacks associated with such a prior art solid ink printer 10.
One such drawback is that a delay of 15 minutes or more may be required for the solid ink printer 10 to warm up sufficiently to melt the solid ink to be used in printing from a powered-off state. Another drawback is that the heating plate 26 requires a large amount of energy in melting blocks of solid ink 12, in heating the printhead assembly 18, and in maintaining the solid ink jet printer 10 in a ready mode.
As such, there is a need to provide solid ink jet printers that consume less energy and also reduce time required for start-up before printing.