Incremental printing of symbolic information – Ink jet – Medium and processing means
Reexamination Certificate
2002-07-08
2004-02-17
Meier, Stephen D. (Department: 2853)
Incremental printing of symbolic information
Ink jet
Medium and processing means
C347S088000, C347S099000, C347S101000, C399S341000
Reexamination Certificate
active
06692121
ABSTRACT:
FIELD OF THE INVENTION
This invention relates to a method for reducing rub-off from a substrate, such as paper, having a toner image on at least one side of the substrate by depositing a quantity of a substantially clear phase change composition on the side of the substrate bearing the image in an amount sufficient to reduce rub-off from the substrate by depositing the phase change composition with an ink jet printer onto a rotary brush in contact with the image side of the substrate to deposit the phase change composition on the image side of the substrate in an amount sufficient to reduce rub-off from the substrate.
BACKGROUND OF THE INVENTION
In electrophotographic printing, digital copying, and copying processes, images are formed on selected substrates, typically paper, using small, dry, colored particles called toner. Toner usually comprises a thermoplastic resin binder, dye or pigment colorants, charge control additives, cleaning aids, fuser release additives and optionally, flow control and tribocharging control surface treatment additives.
The thermoplastic toner is typically attached to a print substrate by a combination of heating and pressure using a fusing subassembly that partially melts the toner into the paper fibers at the surface of the paper substrate. Additionally, the fused toner image surface finish can be controlled by the surface finish on the surface of the fuser roller. Thus, the gloss of the image may be controlled between diffuse (low gloss) and specular (high gloss). If the surface finish of the image is rough (diffuse) then light is scattered and image gloss is reduced.
Typically, in an electrophotographic printer, a heated fuser roller is used with a pressure roller to attach toner to a receiver and to control the image surface characteristics. Heat is typically applied to the fusing rollers by a resistance heater such as a halogen lamp. Heat can be applied to the inside of at least one hollow roller, and/or to the surface of at least one roller. At least one of the rollers is typically compliant. When the rollers of a heated roller fusing assembly are pressed together under pressure, the compliant roller deflects to form a fusing nip. Most heat transfer between the surface of the fusing roller and the toner occurs in the fusing nip. In order to minimize “offset,” which is the amount of toner that adheres to the surface of the fuser roller, release oil is typically applied to the surface of the fuser roller. Typically, the release oil is silicone oil plus additives that improve attachment of the release oil to the surface of the fuser roller, and dissipate static charge buildup on the fuser rollers or fused prints. Some of the release oil becomes attached to the image and background areas of the fused prints.
Fused toner images can be substantially abraded or “rubbed-off” by processes such as duplex imaging, folding, sorting, stapling, binding, filing and the like. Residue from this abrasion process causes objectionable and undesirable marks on non-imaged areas of adjacent pages or covers. This process, and image quality defect, are known as “rub-off” and exist to varying extents in many electrophotographic copies and prints. The basic “requirements” for generation of rub-off are a donor (toner image), a receptor (adjacent paper page, envelope, mailing label, etc.), a differential velocity between donor and receptor, and a load between donor and receptor.
In general, mechanisms of rub-off are consistent with those of abrasive and adhesive wear mechanisms. Relevant factors include: toner toughness, toner brittleness (cross-linking density), surface energy or coefficient of friction of the toner, adhesion of the toner to the paper substrate, cohesive properties of the toner itself, the surface topography of the toner image, the level of load and the differential velocities of the wearing surfaces. Some of these factors are under the control of the machine and materials manufacturers, and some are under the control of the end user.
Toner rub-off may be reduced by the use of tougher toner, lower surface energy toner materials (resulting in lower coefficient of friction), better-fused toner, and a smoother toner image surface finish (but this increases image gloss.)
Unfortunately, there are undesirable consequences associated with each of the above rub-off reduction factors. A tougher toner is more difficult to pulverize, grind, and classify which increases manufacturing costs. Additionally, smaller toner particle size distributions are more difficult to achieve with tougher toner. Adding wax to the toner may provide additional release properties from the fuser roller surface, and add lubrication to the surface of the toner, but triboelectric charging behavior may be adversely affected. A more easily fusible toner may create more toner offset to the surface of the fuser rollers, or increase the tendency of fused prints or copies to stick together in the finisher or output trays. Creating a more specular (smoother) image surface finish increases image gloss, which may be objectionable in some applications. Fuser release oil can lower the coefficient of friction of the fused image, but this effect is temporary since the oil is adsorbed into the paper substrate over time. Fuser release oil can also cause undesirable effects in the rest of the electrophotographic process, especially in duplex printing operations.
Extensive efforts have been directed to the development of improved methods for reducing rub-off without modification of the fusing process.
SUMMARY OF THE INVENTION
According to the present invention, rub-off from a substrate having a front and back side with a toner image on at least one side is reduced. Rub-off is reduced by a method comprising: positioning at least one rotary brush in contact with a toner image bearing side of the substrate; depositing a quantity of a phase change composition on the rotary brush using an ink jet printer; and, rotating the brush to transfer a quantity of the phase change composition to at least one toner image bearing side of the substrate.
REFERENCES:
patent: 3635704 (1972-01-01), Palermiti et al.
patent: 3653932 (1972-04-01), Berry et al.
patent: 3715219 (1973-02-01), Kurz et al.
patent: 3984809 (1976-10-01), Dertouzos et al.
patent: 4250511 (1981-02-01), Stein et al.
patent: 4390369 (1983-06-01), Merritt et al.
patent: 4426653 (1984-01-01), Komada
patent: 4447818 (1984-05-01), Kurata et al.
patent: 4458253 (1984-07-01), Goff, Jr. et al.
patent: 4484948 (1984-11-01), Merritt et al.
patent: 4490731 (1984-12-01), Vaught
patent: 4561789 (1985-12-01), Saito
patent: 4568949 (1986-02-01), Muranaka
patent: 4659383 (1987-04-01), Lin et al.
patent: 4666757 (1987-05-01), Helinski
patent: 4721635 (1988-01-01), Helinski
patent: 4745420 (1988-05-01), Gerstenmaier
patent: 4779558 (1988-10-01), Gabel et al.
patent: 4820346 (1989-04-01), Nowak
patent: 4851045 (1989-07-01), Taniguchi
patent: 4889560 (1989-12-01), Jaeger et al.
patent: 5006170 (1991-04-01), Schwarz et al.
patent: 5084712 (1992-01-01), Hock et al.
patent: 5092235 (1992-03-01), Rise
patent: 5151120 (1992-09-01), You et al.
patent: 5182572 (1993-01-01), Merritt et al.
patent: 5185035 (1993-02-01), Brown et al.
patent: 5270730 (1993-12-01), Yaegashi et al.
patent: 5305026 (1994-04-01), Kazuo et al.
patent: 5327201 (1994-07-01), Coleman et al.
patent: 5339146 (1994-08-01), Aslam et al.
patent: 5353105 (1994-10-01), Gundlach et al.
patent: 5372852 (1994-12-01), Titterington et al.
patent: 5389958 (1995-02-01), Bui et al.
patent: 5406315 (1995-04-01), Allen et al.
patent: 5471233 (1995-11-01), Okamoto et al.
patent: 5495270 (1996-02-01), Burr et al.
patent: 5541624 (1996-07-01), Cooke et al.
patent: 5569540 (1996-10-01), Hirose et al.
patent: 5598195 (1997-01-01), Okamoto et al.
patent: 5614933 (1997-03-01), Hindman et al.
patent: 5672413 (1997-09-01), Taylor et al.
patent: 5677719 (1997-10-01), Granzow
patent: 5751329 (1998-05-01), Bearss et al.
patent: 5771431 (1998-06-01), Mitsuhata et al.
patent: 5796422 (1998-08-01), Hanson et al.
patent: 5808645 (1998-09-01
Crichton John F.
Marsh Dana G.
Heidelberger Druckmaschinen AG
Liang Leonard
Meier Stephen D.
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