Toner



For the Irish surname, see Toner (surname)

Toner is a powder used in laser printers and photocopiers to form the text and images on the printed paper. In its early form it was simply carbon powder. Then, to improve the quality of the printout the carbon was blended with a polymer. Toner particles are melted by the heat of the Laser printer#Fusing, causing them to bind to the paper. The specific polymer used varies by manufacturer but can be a Styrene Acrylate Copolymer or a Polyester Resin. Toner formulations vary from manufacturer to manufacturer and even from machine to machine. Typically formulation, granule size and melt point vary the most.

The original particle size of toner averaged 14–16 micrometres{{cite conference | first = Y. | last = Nakamura | authorlink = | coauthors = Kutsuwada, N. | title = Direct measurement of toner particle size | booktitle = Industry Applications Society Annual Meeting, 1989 | pages = pages 2239–2242 | publisher = IEEE Xplore | date = October 1–[October 5, [ | location = | url = http://ieeexplore.ieee.org/Xplore/login.jsp?url=/iel2/858/3081/00096951.pdf?arnumber=96951 | doi = | id = | accessdate = 2007-08-03 --> or greater. To improve image resolution particle size was reduced, eventually reaching about 8–10 μm for 600 [dots per inch resolution. Further reductions in particle size producing further improvements in resolution are being developed through the application of new technologies such as Emulsion-Aggregation.{{cite web | last = Mahabadi | first = Hadi | authorlink = | coauthors = Stocum, Anne | title = Xerox’s Emulsion Aggregation Toner – An Environmentally Friendly Technology | work = [Xerox | publisher = | date = [2006-08-01 | url = http://www.xerox.com/innovation/Xerox_ea_toner.pdf | format = [PDF | doi = | accessdate = 2007-08-03 --> Toner manufacturers maintain a [quality control standard for [particle size distribution in order to produce a powder suitable for use in their printers.

Toner has traditionally been made by compounding the ingredients and creating a slab which was broken or pelletized and then turned into a fine powder with a controlled particle size range by air jet milling. This process resulted in toner granules that, if viewed under a microscope, showed varying sizes and jagged shapes. To get a finer print, some companies are using a chemical process to grow toner particles. This results in more uniform size and shapes of toner particles. The resulting smaller uniform shapes permit more accurate color reproduction and more efficient toner use.

In earlier machines toner was poured by the user from a bottle into a reservoir in the machine. Modern machines feed directly from a cartridge. Empty cartridges are often refilled by third party vendors.

Toner clean-up Toner can be washed off skin or garments with cold water. Hot or warm water will soften the toner, causing it to fuse to the material it is on. Toner fused to skin will wear off in time, or can be partially removed using abrasive hand cleaners. Toner fused to clothing usually cannot be removed.

Toner particles have electrostatic properties by design and can develop static-electric charges when they rub against other particles, objects, or the interiors of transport systems and vacuum hoses. Because of this and the small particle size, toner should not be vacuumed with a conventional home vacuum cleaner. Static discharge from charged toner particles can ignite dust in the vacuum cleaner bag or create a small explosion if sufficient toner is airborne. This may damage the vacuum cleaner or start a fire. In addition, toner particles are so fine that they are poorly filtered by conventional household vacuum cleaner filter bags and can blow through the motor or back into the room.

If toner spills into the laser printer, a special type of vacuum cleaner with an electrically conductive hose and a high efficiency (HEPA) filter may be needed for effective cleaning. These are called Electrostatic discharge-safe (Electrostatic Discharge-safe) or toner vacuums. Similar HEPA-filter equipped vacuums should be used for clean-up of larger toner spills.

Toner is easily cleaned from most water-washable clothing. Because toner is a wax or plastic powder with a low melting temperature, it must be kept cold during the cleaning process. Washing a toner stained garment in cold water is often successful. Even warm water is likely to result in permanent staining. The washing machine should be filled with cold water before adding the garment. Washing through two cycles improves the chances of success. The first may use hand wash dish detergent, with the second cycle using regular laundry detergent. Residual toner floating in the rinse water of the first cycle will remain in the garment and may cause a permanent graying. A clothes dryer or iron should not be used until it is certain that all toner has been removed.

Health risks As a fine powder, toner can remain suspended in the air for some period, and is considered to have health effects comparable to inert dust. It can be an irritant to people with respiration (physiology) conditions such as asthma or bronchitis. Following studies on bacterium in the 1970s that raised concerns about health effects resulting from pyrol, a contaminant created during manufacture of the carbon black used in black toner, manufacturing processes were changed to eliminate pyrol from the finished product.

According to recent research, some laser printers emit submicrometer particles which have been associated in other environmental studies with respiratory diseases .{{cite news | last = Morawska | first = Lidia | coauthors = co-authors: He, Congrong; Taplin, Len | title = Particle Emission Characteristics of Office Printers | work = International Laboratory for Air Quality and Health ([Queensland University of Technology); Queensland Department of Public Works | pages = 1–7 | language = | publisher = SF Gate | date = [2007-07-10 | url = http://cdn.sfgate.com/chronicle/acrobat/2007/08/01/printer_es063049z.pdf | accessdate = 2007-08-03 -->

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