Xerox Goes With Solid Ink Due to Diminishing Cost

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Trip
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Xerox Goes With Solid Ink Due to Diminishing Cost

Post by Trip » Sun Oct 04, 2009 6:05 pm

Xerox's Benefits Page
# Less waste than color laser printers with no cartridges to dispose of and far less packaging to add to landfills
solid ink's environmental benefits (PDF)
# Non-toxic ink is safe to handle by even small children
# Recycled paper of any kind can be used with the same high-quality results
# Fewer CO2 emissions and less fuel is used from shipping because solid ink packages are smaller and lighter than toner cartridges
# Less energy is used to manufacture solid ink because of the simplicity of the design
In a few more years, hopefully we'll see solid ink at the consumer level.

Wikipage on solid ink lists some notable weaknesses.
Print Durability
A page printed on the highest quality print setting can have the ink scraped off rather easily with a fingernail. Lower quality print settings do not pile up as much ink and are more durable but the ink can still scrape off.
Warm-up time
When the device is cold the first page may take several minutes to print. However, once the printer is warmed up, the time to print the first page is negligible.
Power consumption
The ink must be heated and a large portion of the printing mechanism must be kept at or near the ink's melting point during use. When the printer is in "sleep mode", most units keep a small pool of each color wax within the printhead heated to temperature just above the ink's "freeze point". According to the Xerox service manual, this consumes about 50 watts.
Excessive Ink Usage
Every time the printer loses power for long enough to cause the portion of ink which was being kept above its "freeze point" in the printhead to drop below that temperature, the mass of ink in each reservoir would have contracted in size enough as a result of the cooling to permit air to enter the printhead, which would result in print aberrations until the printhead reservoirs had been refilled by the ink melter assembly above it. As a result, the printhead is then purged using a vacuum pump, causing some ink to be flushed from the printhead's holding tanks into the waste tray to remove the air from the printhead. (Xerox printers have a "waste ink" tray for this purpose. Since all four inks are dumped into a unified "waste ink" tray, it is impossible to reuse the lost ink since the four process colors coalesce to form a single solid mass in the tray, which look much like solidified candle wax drippings, but almost black.) If the printer was in its sleep state, less time without power would be required to necessitate a purge cycle than if the printer was in its ready-to-print state (since the printhead is kept much hotter when ready-to-print).
Printer damage from moving [if not careful]
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. Cool down time by merely removing mains power is recommended as 30 minutes, but 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. Moving the printer before cool down completes can damage the print head by spilling molten ink between reservoirs of different color as well as over other components inside the printer (motors, belts, et cetera), and is not covered under maintenance or warranty.
Incompatible with laser printers
Not appropriate for letterhead printing or uses where the document will later be fed through a black/white laser printer. The heat from the laser fuser will cause the wax ink to discolor, fade, or contaminate the laser printer.
Ultraviolet resistance
Using organic colourants, solid ink prints are sensitive to the sun's ultraviolet light, and color fades with sunlight exposure over time. This problem is the same with inkjet printers dyes, but laser printers are immune to that, using mineral pigment toner.
Some strengths:
Print Quality
Due to the way solid ink printers put the ink onto the page, print quality is considered to be excellent with lively colors. Excellent results can be achieved with low-quality stock, as the wax covers the stock with a glossy surface.
First print time [after warmed up]
When warmed up, solid ink printers have one of the fastest first page out time of any printing technology.
Ozone
Solid ink printers do not produce ozone, making them more friendly to the environment and better for office workers than laser technology.

Trip
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Post by Trip » Sun Oct 04, 2009 6:10 pm

Judging from that, it's best suited for an office environment where it's frequently used (already warmed up). The print durability issue would be significant though...

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