2. Photocopying
Xerography
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3. Process
http://content.answers.com/main/content/img/CDE/ELECFOTO.GIF
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4. Applications
• Duplicating documents efficiently and cheaply (i.e.
duplicating 500 handouts)
• Xerography has been adapted to eliminate the hand-
inking stage in traditional animation. Animated films
produced with this method include 101 Dalmatians
(1961) and The Secret of NIMH (1982)
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5. Advantages
• Cheap
• Quick (~60 pages per minute)
• Allows user to alter size of the page
• Digital photocopiers can collect incremental pages
together (so books can be photocopied without being
sorted afterwords)
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6. Disadvantages
• Finding individual pages to scan wastes time
• Takes up a lot of space
• Its most common use - photocopying textbook pages,
violates copyright and the DMCA
• Older photocopiers use ultraviolet light - which some
say is harmful to health
• Toner produces ozone, volatile organic compounds,
selenium, cadmium sulfide, nitrogen oxide and carbon
monoxide
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7. An example of a photocopied sheet
(http://jfk.ci.dallas.tx.us/30/3028-001.gif)
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9. Process
1. Plate cylinder is dampened and inked
2. Because of the repulsion of the oil-based ink and water,
the ink is transferred onto the offset cylinder
3. The offset cylinder prints the ink onto the paper.
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10. The process of Offset Lithography
http://en.wikipedia.org/wiki/File:Offset.png
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12. An use of Offset Lithography
http://homepages.which.net/~rex/bourne/photos/newspapers.jpg
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13. Advantages
• Good reproduction quality (esp. photos)
• Cheap - the more you print, the less you pay
• Ability to print on a wide range of papers
• Fast
• Widely available
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14. Disadvantages
• Color variation due to water and ink mixture
• Paper can stretch due to dampening
• Needs to be done in a large factory
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16. Process - platemaking
1. A film negative is placed over a flexible light-sensitive
polymer, which is then exposed to UV light. The polymer
hardens where the light has passed through, but the rest of
the polymer stays relatively soft.
2. The softer polymer is then washed away by water or
solvent.
3. Other methods to produce the plate: Computer guided
laser-etching and molding.
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17. Process - printing
1. The flexible plate it then wrapped around a plate cylinder.
2. The ink is drawn from the ink tank to the Anilox roller,
whose texture is specifically designed to retain a small
amount of ink. Excess ink is removed by the ‘doctor blade’.
3. The Anilox roller transfers the ink onto the plate, which
transfers the ink onto the paper which is squashed between
the plate cylinder and impression cylinder.
4. Flexographic inks include: Solvent-based Inks, Water-based
Inks, Electron Beam curing inks and Ultra-Violet curing Inks.
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18. The process of Flexography
http://glossary.ippaper.com/images/graphicsedviser/print/flexo.jpg
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19. Applications
• Brown corrugated boxes
• Flexible packaging (i.e. retail and shopping bags)
• Food and hygiene bags and sacks
• Milk and beverage cartons
• Flexible plastics
• Self adhesive labels
• Disposable cups and containers
• Envelopes
• Wallpaper
• Cheap magazines, Newspapers and Paperback books
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20. An use of Flexography
http://eng.amipak.by/i/photo/page/production/print/print03-big.jpg
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21. Advantages
• Fast
• Relatively cheap to set up
• Can use the same apparatus as letterpress
printing
• Can utilize a wide variety of inks
• Can print on a wide variety of materials
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22. Disadvantages
• Cannot accurately reproduce fine detail
• Color may not be consistent
• Individual presses have to be prepared for
each different print
• Poor shadows
• Impression per print is more limited than
Offset lithography
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23. Gravure
or Rotogravure
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24. Process
1. A image is etched onto the surface of a
metal cylinder.
2. The etched area is filled with ink.
3. The cylinder is rotated, printing onto the
paper.
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25. The process of Gravure printing
http://www.istc.illinois.edu/info/library_docs/manuals/printing/images/ch8fig10.jpg
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26. Applications
• High quality art and photo books
• Postage stamps and postcards
• Packaging
• Expensive magazines (glossy covers)
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27. An use of Gravure printing
http://www.ashtreelabels.com/images/sleeving/sleeve%20products%201.jpg
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28. Advantages
• Consistent color
• High speed
• Good results on cheap paper
• Very durable printing plate
• Ink dries on evaporation - paper can pass
through multiple machines for color prints
with CMYK
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29. Disadvantages
• High costs of printing plates and cylinders
• Only good for long print runs
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31. Process
1. A screen is made with a fine, porous fabric
(i.e. silk or polyester) and fitted over a
wooden frame
2. Areas are blocked off with a non-permeable
substance to form a negative
3. The screen is placed above paper or fabric
and ink placed into the mesh via a floodbar,
printing on the paper.
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32. The process of Screenprinting
http://en.wikipedia.org/wiki/File:Silketrykk.svg
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33. Applications
• T-shirts
• Posters
• Plastic and Metal signage
• Point-of-sale displays
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34. An use of Screenprinting
http://handmadetees.com/images/hmt-t-shirt.jpg
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35. Advantages
• Economical for short runs
• Stencils are easy to produce
• Can print on virtually any material
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36. Disadvantages
• Difficult to achieve fine detail
• Low output
• Print requires long drying time
• Has to be done manually
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37. Sources
• Textbook
• Wikipedia
• Google image search
• About.com
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