Fuser

Sihcone contamination has been impHcated as a cause of failure in telephone switching systems and other devices that contain relay switch contacts (507). Analysis of airborne particulates near telephone switching stations showed the presence of siUcones at these locations. Where the indoor use of sihcones is intentionally minimised, outdoor levels were found to be higher than inside concentrations (508). Samples of particulates taken at two New Jersey office buildings revealed sihcone levels that were considerably higher indoors than outdoors. In these cases, indoor sihcone aerosols are beheved to be generated primarily by photocopiers, which use sihcone fuser oils. 

Step 6 Fixing or fusing. The toner image is permanently fixed to the paper using either a heat-and-pressure mechanism (hot-roll fuser) or a radiant fusing technology (oven fuser) to melt and bond the toner particles into the medium (usually paper) being printed on. 

Kaplan [4] prepared fluorochemical release agents, (IV), for use as fluoroe-lastomer fuser component in electrostatographic reproducing equipment. 

Toners are comprised of a colorant in a resin binder. The colorant concentrations are typically 10%. Depending on the application, additional components may include additives to control the charge level, surface additives to control flow and cleaning, and/or waxes to prevent toner adhesion to the fuser roller. For black and white applications, the most common colorant is carbon black. The role of the resin is to bind the toner to the receiver, thus creating a permanent image. The choice of the resin depends on the fusing process. 

For the above reasons, processes that involve combinations of heat and pressure are the most widely used. This is normally accomplished by hot-roll pressure devices in which at least one roll is heated with a quartz lamp (Lee, 1975 Prime. 1983 Kuo. 1984 Hiraoka et al.. 1993). Offset of the toner to the fuser roll can be avoided by the use of special oils wicked onto the surface of the roll. Most roller fusing devices use heated rolls coated with silicone or fluorocarbon elastomers. Composite layer structures with multiple layers for improved process lifetime are becoming more common. Figure 17 shows a cross-section of a typical fuser roller and Fig. 18 shows a typical fusing process. For a review of fusing materials, see Gruber et al. (1989). For a discussion of the effects of paper properties on fusing, see Sanders et al. (1996). 

During fuser-roll resist lamination processes, the copper-clad FR- substrate surface temperature was found to be inversely proportional to the substrate thickness. This temperature fluctuation has resulted in changes of adhesive forces in the copper/resist interface which in turn can affect the yield in the printed circuit manufacturing processes. By using infrared preheat... 

Ripsom and Wopschall suggested a linear relationship between logarithmic Riston 3600 resist viscosity and temperature. At 25 C, the resist viscosity was reported to be 10 poises. At 100 C, the viscosity would decrease to 10 poises. Hence, there is over 3 orders of magnitude drop in resin viscosity as the temperature is raised from room temperature to 100 C, which is 5 degrees below the typical fuser roll lamination... 

Dry Film Lamination The resist lamination was performed using a Model 712 Hot Roll Laminator supplied by MacDermid, Inc., Waterbury, Connecticut. The heart of the lamination system is an aluminum-cored fuser roll which is about 2.3 inches in diameter and is coated by 0.1 inch thick additives-filled silicon rubber. Figure 3 shows a schematic of the fuser roll. All dry film lamination experiments were performed using a conveyor speed of 20 inches per minute an air-assisted pressure of 0 PSIg and a fuser roll temperature of 103 C. The hold time between surfece treatment and resist lamination was kept constant at 60 minutes. 

IEIX TF,STE ERDA,CHEN A, Engel P. Thesdectins vascular adhesion molecules, fuser 9 866-873,1995. 

Both of these rollers are operated with a special electric motor known as an electronic stepper motor. This type of motor can accurately move in very small increments. It powers all of the paper transport rollers as well as the fuser rollers. 

To solve this problem, EP laser printers incorporate a device known as a fuser (Eigure 7.8), which uses two rollers that apply pressure and heat to fuse the plastic toner particles to the paper. You may have noticed that pages from either a laser printer or a copier (which uses a similar device) come out warm. This is because of the fuser. 

Before any of these steps can begin, however, the controller must sense that the printer is ready to start printing (toner cartridge installed, fuser warmed to temperature, and all covers are in place). Printing cannot take place until the printer is in its ready state, usually indicated by an illuminated Ready LED light or a display that says something like 00 READY (on HP printers). 

In the final step, the fusing step, the toner image is made permanent. The registration rollers push the paper toward the fuser rollers. Once the fuser grabs the paper, the registration rollers push for only a short time more. The fuser is now in control of moving the paper. 

As the paper passes through the fuser, the 350-degree F fuser roller melts the polyester resin of the toner and the rubberized pressure roller presses it permanently into the paper (Figure 7.14). The paper continues on through the fuser and eventually exits the printer. 

Once the paper completely exits the fuser, it trips a sensor that tells the printer to finish the EP process with the next step, the cleaning step. At this point, the printer can print another page and the EP process can begin again. 

Never run transparencies through a laser printer without first checking to see if it s the type recommended by the printer manufacturer. The heat from the fuser will melt most other transparencies and they will wrap themselves around it. It is impossible to clean a fuser after this has happened. The fuser will have to be replaced. Use ONLY the transparencies that are recommended by the printer manufacturer. 

The whole fuser may not need to be replaced. Fuser components can be ordered from parts suppliers and can be rebuilt byyou. For example, if the fuser has a bad lamp, you can order a lamp and replace it in the fuser. 

Another problem similar to this is when there are small areas of smudging that repeat themselves down the page. Dents or cold spots in the fuser heat roller cause this problem. The only solution is to replace either the fuser assembly or the heat roller. 

Warming Up The fuser is being warmed up before the 00 Ready state. 

Service A fuser error has occurred. Most commonly caused by fuser lamp failure. Power off the printer and replace the fuser to solve. Printer will not print as long as this error exists. 

Does the fuser heat lamp light up after the main motor finishes its rotation ... 

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