For ink cartridges with print heads or for printer units with built-in print heads, the print head functions in the same way as engines do for cars. It contains the nozzle assemblies where a small amount of ink is temporarily stored. Once the computer directs the printer to print, the nozzle resistor will heat the small amount of ink stored. The heated ink is then forced to drop through the nozzle to the paper.
Since the print head has a small heater and since the ink passing through it to the nozzle is hot, it is inevitable for the print head to suffer a burnout. Technically, the ink that flows through each part of the nozzle assembly does not only function as the means to give a printout. It also functions both as a lubricant and as a coolant for the nozzle. If the tiny ink chamber in the nozzle assembly does not have an ink supply in it, the whole assembly will warp quickly and break apart when the resistor heats up. Keep in mind that the nozzle resistor can heat up and reach a temperature within the hundred degrees range in a short span of time.
Not replacing the ink cartridge immediately or allowing the ink to dry up or to drain can initiate the burnout process in ink cartridges. In this case, the damage in the cartridge brought about by the burnout may range from simple print quality issues to severe damages on the printer. Yes, a print head burnout may sacrifice print quality by imparting streaks or lines across the page, bad colorations and light or dark patches on the printout. This is one of the reasons why it is not advisable to attempt to print if you know that your ink cartridge is going empty.