Hello,

We noticed you're browsing in private or incognito mode.

To continue reading this article, please exit incognito mode or log in.

Not an Insider? Subscribe now for unlimited access to online articles.

Intelligent Machines

Tiny Bubbles

Desktop printing was revolutionized by a misplaced soldering iron.

Inkjet printers that commit electronic words and images to paper inhabit most computer-equipped homes and offices. Costing as little as $100, the machines form a multibillion-dollar industry. But the road to that market required some twists and turns, including a serendipitous lab accident.

In the late 1970s, Canon was one of several companies pursuing inkjet technology to create text and pictures at resolutions much higher than dot-matrix printers could achieve. Like its competitors, the Canon team was trying to use pressure to push tiny, controlled amounts of ink out of nozzles. Their initial plan was to fabricate the nozzles out of a piezoelectric material; electronic signal pulses would deform the nozzle so that it would first suck ink into a chamber, then force it out. But that approach was abandoned in 1977 shortly after a carelessly placed soldering iron touched the tip of an ink-filled syringe-and changed the direction of their research. The hot tool boiled the ink, and as the bubbles expanded, they forced the ink out of the syringe. Canon’s Ichiro Endo realized that heat might lead to a better approach. (A Hewlett-Packard team independently hit on the same idea in 1978.)

Canon demonstrated the prototype “bubble jet” printer in 1981; a commercial version debuted in 1985. Other companies, including Lexmark and Xerox, adapted and enhanced the technology. Epson went on to develop inkjet printers using piezoelectric technology. In today’s thermal inkjet printers, tiny heating elements reach temperatures of 500 C, vaporizing minute amounts of ink for a few millionths of a second. As bubbles form and expand, nozzles like those shown above eject droplets of ink as small as four trillionths of a liter. Print heads containing 300 to 600 such nozzles squirt thousands of drops per second as they scan back and forth across a sheet of paper.

This story is part of our January/February 2001 Issue
See the rest of the issue
Subscribe

Researchers are now using inkjet printers to spray more than just ink. Last May, Sandia National Laboratories used an HP printer to deposit self-assembling nanostructures that could one day form ready-to-use sensor arrays or photonic circuits. Even PC circuits might be printed using piezoelectric inkjets if research at MIT’s Media Lab pans out (see “Print Your Next PC,” TR November/December 2000).

Want to go ad free? No ad blockers needed.

Become an Insider
Already an Insider? Log in.
More from Intelligent Machines

Artificial intelligence and robots are transforming how we work and live.

Want more award-winning journalism? Subscribe to Insider Plus.
  • Insider Plus {! insider.prices.plus !}*

    {! insider.display.menuOptionsLabel !}

    Everything included in Insider Basic, plus the digital magazine, extensive archive, ad-free web experience, and discounts to partner offerings and MIT Technology Review events.

    See details+

    What's Included

    Unlimited 24/7 access to MIT Technology Review’s website

    The Download: our daily newsletter of what's important in technology and innovation

    Bimonthly print magazine (6 issues per year)

    Bimonthly digital/PDF edition

    Access to the magazine PDF archive—thousands of articles going back to 1899 at your fingertips

    Special interest publications

    Discount to MIT Technology Review events

    Special discounts to select partner offerings

    Ad-free web experience

/3
You've read of three free articles this month. for unlimited online access. You've read of three free articles this month. for unlimited online access. This is your last free article this month. for unlimited online access. You've read all your free articles this month. for unlimited online access. You've read of three free articles this month. for more, or for unlimited online access. for two more free articles, or for unlimited online access.