Page 186 - Graphic Design and Print Production Fundamentals

174 Chapter 6. Imaging

Figure 6.10 Fusing

Along with the transfer stage, fusing can be greatly affected by the paper or substrate used. The thicker
and heavier the sheet, the more heat it absorbs. Because of this, these sheets require higher temperatures
so there is sufficient heat remaining to melt the toner. Insufficient heat can cause the toner to scratch off
easily or not bond at all. Too much heat can cause moisture in the substrate to evaporate quickly and get
trapped beneath the toner causing tiny bubbles that prevent the toner from sticking wherever they occur.
This issue is seen more on thinner stocks that do not absorb as much heat. Too much heat can also cause
toner residue to stick to the heater roller and deposit it on subsequent sheets.

The heat roller can heat up quite quickly but may take much longer to cool down. This can cause delays
in producing work that switches between different paper weights. To combat this, some devices use a
thin belt that can be both heated and cooled quickly in place of the heater roller. In some cases, a cooling
mechanism is also employed further mitigating the cooling lag.

Media Attributions

• EP Imaging System – Complete by Roberto Medeiros
• EP Imaging System – Charging by Roberto Medeiros)

• EP Imaging System – Development by Roberto Medeiros
• EP Imaging System – Transfer by Roberto Medeiros