A block of solid ink looks more like a child's chunky crayon than the outcome of thousands of research hours and millions of research dollars, but the little lightweight cubes of colour are a major building block in Xerox's business plans.

Formed from a secret mix of vegetable fat, tree sap, resin from oil sources, and either wax or plastic (depending on whether you are talking to a Xerox chemist or engineer - chemists can get quite worked up about the difference), the colour "sticks" come in the printer's colours of magenta, cyan blue, yellow and black. Each two-inch stick comes in one of four shapes depending on the colour, making it impossible to load magenta into the cyan slot of a solid ink printer.

The solid ink becomes liquid when heated within the printer and is pumped onto the drum inside the printer through tiny holes in the print head, which transfers the image to paper. The ink cools immediately on contact with paper, forming a crisp image. The resulting document has the feel of an offset printed document, with richer colour than an inkjet printer.

The basic technology came via a company in Oregon called Tektronix, which originally developed solid ink in the 1980s. Xerox bought Tektronix's printing division in 2000, and all solid ink manufacturing and most research now takes place at the former Tektronix buildings in Wilsonville, outside Portland, Oregon.

There, employees crank out 200,000 colour sticks daily and manufacture the delicate print heads, formed by layering and binding together gold-plated strips of metal punctured with 1,236 minuscule holes that form channels for spraying the melted ink on to the drum.

In a nearby building, chemists experiment with new ink recipes while engineers ponder future printer designs. An extraordinary amount of research and engineering goes into the process that appears simple to the end user.