Printing Supply

Modern printing technology

Across the world, over 45 trillion pages (2005 figure) are printed annually.[11] In 2006 there were approximately 30,700 printing companies in the United States, accounting for $112 billion, according to the 2006 U.S. Industry & Market Outlook by Barnes Reports. Print jobs that move through the Internet made up 12.5% of the total U.S. Printing market last year, according to research firm InfoTrend/CAP Ventures.

Books and newspapers are printed today using the technique of offset lithography. Other common techniques include:

    * flexography used for packaging, labels, newspapers
    * relief print, (mainly used for catalogues),
    * screen printing from T-shirts to floor tiles
    * rotogravure mainly used for magazines and packaging,
    * inkjet used typically to print a small number of books or packaging, and also to print a variety of materials from high quality papers simulate offset printing, to floor tiles; Inkjet is also used to apply mailing addresses to direct mail pieces
    * hot wax dye transfer
    * laser printing mainly used in offices and for transactional printing (bills, bank documents). Laser printing is commonly used by direct mail companies to create variable data letters or coupons, for example.
    * pad printing for applying a flat image on a curved substrate.

 Gravure

Gravure printing is an intaglio printing technique, where the image to be printed is made up of small depressions in the surface of the printing plate. The cells are filled with ink and the excess is scraped off the surface, then a rubber-covered roller presses paper onto the surface of the plate and into contact with the ink in the cells. The printing plates are usually made from copper and may be produced by digital engraving or laser etching.

Gravure printing is used for long, high-quality print runs such as magazines, mail-order catalogues, packaging, and printing onto fabric and wallpaper. It is also used for printing postage stamps and decorative plastic laminates, such as kitchen worktops.

 Digital printing

Digital printing accounts for approximately 9% of the 45 trillion pages printed (2005 figure) around the world.[11]

Printing at home or in an office or engineering environment is subdivided into:

    * small format (up to ledger size paper sheets), as used in business offices and libraries
    * wide format (up to 3' or 914mm wide rolls of paper), as used in drafting and design establishments.

Some of the more common printing technologies are

    * line printing—where pre-formed characters are applied to the paper by lines
    * daisy wheel—where pre-formed characters are applied individually
    * dot-matrix—which produces arbitrary patterns of dots with an array of printing studs
    * heat transfer—like early fax machines or modern receipt printers that apply heat to special paper, which turns black to form the printed image
    * blueprint—and related chemical technologies
    * inkjet—including bubble-jet—where ink is sprayed onto the paper to create the desired image
    * laser—where toner consisting primarily of polymer with pigment of the desired colours is melted and applied directly to the paper to create the desired image.

Vendors typically stress the total cost to operate the equipment, involving complex calculations that include all cost factors involved in the operation as well as the capital equipment costs, amortization, etc. For the most part, toner systems beat inkjet in the long run, whereas inkjets are less expensive in the initial purchase price.

Professional digital printing (using toner) primarily uses an electrical charge to transfer toner or liquid ink to the substrate it is printed on. Digital print quality has steadily improved from early color and black & white copiers to sophisticated colour digital presses like the Xerox iGen3, the Kodak Nexpress and the HP Indigo Digital Press series. The iGen3 and Nexpress use toner particles and the Indigo uses liquid ink. All three are made for small runs and variable data, and rival offset in quality. Digital offset presses are called direct imaging presses; although these receive computer files and automatically turn them into print-ready plates, they cannot insert variable data.

Small press and fanzines generally use digital printing or more rarely xerography. Prior to the introduction of cheap photocopying the use of machines such as the spirit duplicator, hectograph, and mimeograph was common.