Solid ink

This allowed chemists to expand Solid inks into a new direction and led to a Three-Dimensional printing patent from an ex-Howtek employee who formed the company Visual Impact Corporation.

A loose ink block does not leave any residual cartridge after it is consumed - only a crushable, thin, plastic packing bag or tray and a recyclable cardboard packaging box.

This is because melted solid ink that has subsequently cooled and re-solidified inside the ink-delivery pathways is a normal part of printer operation.

And, while the printer is not operating, the solidified wax helps to prevent oxygen and moisture from interacting with many internal parts of the ink-delivery components.

In the 1990s, the president of Tektronix ate a piece of solid ink, derived from food-grade processed vegetable oils, to demonstrate their safety.

When the printer is in "sleep mode", most units keep a small pool of each color wax within the printhead heated to a temperature just above the ink's "freeze point".

The printer contains melted wax when at operating temperature, and owners' manuals warn that it cannot be moved until it has completed a special cool-down cycle selected from the machine's control panel.

However, all modern solid-ink printers have a shutdown cycle which use fans to solidify the ink in less than ten minutes, with the added benefit of physically restraining the printhead to prevent damage during moving or shipping.

The manuals warn that substantial damage is possible otherwise, requiring servicing by a trained technician if not properly cooled down before moving the printer.

Because of the liquid-ink-spillage concern, solid-ink printers are not suitable for mobile usage, such as on movable carts for printing pricing tags in retail settings.

Paper dust may also accumulate as debris inside the printer; this could cause abrasions on the drum and may mimic a weak or missing jet.

For this reason, the basic built-in drum-cleaning procedure is therefore recommended to be invoked at least three times before initiating printhead-nozzle cleaning cycle.

Liquid metal was referred to as hot-melt "type" ink in this patent, and it was introduced before the term "3D printing" was in use.

In 1982, Robert Howard had the idea to build a small color printer system before he left Centronics Corporation.

Richard Helinksi formed C.A.D.-Cast, Inc. on October 27, 1989 (renamed to Visual Impact Corporation),[6] a 3D printer company to build the Sculptor but later gave up after receiving a 3D Patent US 5136515A on August 4, 1992, and licensed it to Sanders Prototype, Inc. in 1993.

Piezo manufactures still insist the operating temperatures are dangerously high but the Howtek printheads work fine.

The next color solid ink printer, the Tektronix PhaserJet PXi, was introduced in June 1991 at a cost of nearly $10,000 US.

Robert Howard Research introduced the completely different solid ink in 1985 with the HT-1 printer, later named Pixelmaster that shipped in 1986 from Howtek, Inc, Hudson, NH.

The Howtek solid ink (called thermoplastic) was molded in 4 different color shapes to fit into the Pixelmaster and later in the Braillemaster printers.

Delays from the litigation and Yen exchange rate changes increased the cost of the Pixelmaster printer and sales dropped of by the late 1980s.