On the 30th anniversary of their invention at HP Labs, HP’s first inkjet printers turn 25.

March 12, 2009 -- Thirty years ago this week, HP Labs launched a research project destined to reshape the printing industry and the company itself.

It began as a quest to create a portable printer for HP’s popular scientific calculators. In March, 1979, HP Labs team working on thin-film technology suggested a design using a novel thermal inkjet mechanism with the potential to be miniaturized and mass-produced. HP quickly patented the concept and company researchers set to work developing what was to become one of the company’s most successful ever product lines.

Exactly five years later, in March, 1984, HP announced the introduction of the HP ThinkJet, the world’s first mass-marketed, personal inkjet printer.

Before the HP ThinkJet, most home and office printers used daisy wheels, spinning balls or dot-matrix heads to strike ink-soaked ribbons. These ‘impact’ printers were prone to mechanical failure, noisy to operate, and the more affordable they were, the worse the quality of their print. Continuous inkjet printing did exist at the time, but only for very large format lettering. Laser printers, meanwhile, offered "letter-quality" printing but the least expensive models cost over $100,000.

HP learned early that the most advanced print-related technologies reside in the printer cartridge, not in the printer.

HP learned early that the most
advanced print-related technologies
reside in the printer cartridge, not
in the printer.

In contrast, HP’s thermal inkjet technology promised quiet operation, high print quality, a range of font and graphics capabilities, extremely low power consumption and, eventually, high-quality, low-cost color. Most importantly, the HP design (which used thermal heating to bubble tiny droplets of ink through a fine nozzle onto the paper) could be produced at a low enough cost to make a disposable print cartridge – allowing inkjet technology to be used in a low-priced, mass-market printer for the first time.

HP’s original ThinkJet, launched in March 1984, offered a 96-dpi output at a print speed of 150 characters per second and was priced at $495. Today’s HP DeskJets print up to 30 pages a minute, offer a color resolution of 4800 x 1200 dpi and retail for as little as $39.99.

In the last three decades, HP has become the leading supplier of printing and imaging technology to corporations and individuals worldwide. The company has so far shipped more that 400 million individual inkjet printers.

Information provided courtesy of HP Archives.