For over 30 years, Barry Fox has trawled the world's weird and wonderful patent applications each week, digging out the most exciting, intriguing and even terrifying new ideas. His column, Invention, is now available exclusively online. Please send us your feedback.

Used tyre printer ink

Printer ink can cost as much as vintage champagne, so finding a cheap way to make the stuff would be a godsend. Now three inventors from Derbyshire, UK, think they have just the solution: extract the carbon from unwanted tyres to generate a cheap and plentiful supply.

The black carbon powder used in regular ink is refined from pure oil and the liquid used in cartridges is boiled down from a volume six times larger. On the other hand, millions of tyres are dumped every year.

Baking a tyre at 800°C should break it into a mucky mix of fused silica, steel wire, sulphur, and lumps of precious carbon char, the inventors say. Shaking the mixture through a magnetic sieve ought to get rid of lumps and metal, and then re-baking the smaller particles should produce semi-pure carbon powder.

Flushing this through with hydrochloric acid will suck out any remaining metal and sulphur, and caustic alkali should remove any silicon bits, to produce usable carbon power.

As an added bonus, the inventors claim the entire process will release far less carbon dioxide into the atmosphere than the traditional refinement process.

Read the ink-from-tyres patent here (pdf format).

Self-healing switch

When electronic equipment fails, it is all too often down to a faulty switch. So a component that miraculously mends itself could be revolutionary.

Honeywell of New Jersey, US, is developing just such a switch. It self-repairs the natural wear and tear experienced by the surface contacts used to open and close an electrical circuit.

The company's switch has two platinum contact pads with spiral grooves in their surface, filled with gallium metal. The metal remains solid normally, but liquefies slightly in response to the heat generated by electrical contact.

So, erosion to the contact pads, caused as sparks bridge the circuit gap, is naturally smoothed out as the metal rearranges itself within the grooves. Honeywell believes the switch could be equally suited to mission-critical electronics and the latest must-have gizmos and gadgetry.

Read the self-healing switch patent here (pdf format).

Screen blur

The shuddering video effect produced when an antiquated computer tries to cope with the latest snazzy 3D software could soon be thing of the past.

Microchip maker Intel thinks deliberately blurring a video image could smooth out the jerkiness generated when an overworked graphics card is forced to drop multiple frames from a continuous video sequence.

The blurring effect is triggered when a graphics chip receives more data than it can process efficiently. The chip then reduces the resolution of each frame and employs fewer frames to produce the streaming output. The picture will be less sharp, but far smoother overall. And, as soon as the card is able to cope again, the picture returns to full clarity.

The technique promises to let even the cheapest PC system handle the high-end software packages, and could be a blessing when the next version of Microsoft's Windows launches, complete with dazzling 3D effects.

Read the screen blur patent here (pdf format).