The bubble jet technology used by Canon Inc in the integral printer in its new BN22 BJ all-in-one notebook computer (CI No 2,114), was first patented by Canon in 1977. The process involves heating ink to temperatures of 400oC in microscopic nozzles. This causes a bubble of ink to shoot out of the nozzle. Once the ink is expelled, the heat is turned off, the ink bubble contracts and a vacuum is formed in the nozzle, pulling fresh ink back into it so that the process can begin again. Canon used mechatronics – electronically controlled precision mechanics to produce the miniature printer. The project took a year – and some 171 additional patents to complete. The resulting printer produces 360 dpi output, suitable for text and graphics, and prints at 116 characters per second – around a page a minute. It conforms to the X24E, BJ-130e and LQ-510 emulations and its automatic sheet feeder can handle up to 10 sheets at a time. On-screen guidelines are given for changing the ink cartridge, which does 60 pages at a cost of around 2.5 pence each.
