Glossary Of Terms

The PRINTING United Alliance Glossary of Terms serves as an excellent industry terminology resource. It is the language by which we all communicate, without it universal understanding would be impossible. Language and our ideas about how it is interpreted change rapidly. PRINTING United Alliance is aware of this and continues its effort to keep our constituents well informed about changes to the increasingly complex industry terminology. The definitions are for general reference only. Usage may vary between companies, individuals, or national and country customs. The information presented is as accurate as the authors and editors can ascertain and PRINTING United Alliance assumes no responsibility for the use of information presented herein.


  • Organic color
    Raw materials derived from animal or vegetable origin.
  • Organic peroxide
    An organic compound that contains a structural deviation of hydrogen peroxide, where one or both of the hydrogen atoms has been replaced by an organic radical.
  • Organic pigment
    Raw material colorant that is derived from coal tar or its derivatives, usually stronger and brighter than inorganic pigments.
  • Organic solvent
    Organic material including diluent and thinner that are liquid at standard conditions and are used as dissolvers, viscosity reducer or cleaning agent.
  • Organosol
    A suspension of resin particles in organic solvent typically made with vinyl resin or plasticizers.
  • Orientation
    (1) The direction a page is printed, horizontal (landscape), vertical (portrait); (2) The condition of polymers being positioned in a direction parallel to the fiber length, as in a polyester mesh fiber that has been highly tensioned.
  • Oriented polystyrene (OPS)
    A transparent glass-like polymerized styrene material, not modified for impact, heat resistance, solvent and chemical resistance.
  • Origin
    Place marking the zero coordinate on the x, y, or z axis.
  • Original
    A design, material, or subject to be copied or reproduced.
  • Original equipment manufacturer (OEM)
    (1) A company that sells goods to another company for use as components in their own equipment or for resale to end user; (2) A firm that licenses other companies to sell their products.
  • Orthochromatic (film)
    (1) photographic surface insensitive to red but sensitive to ultraviolet blue, green and yellow rays; (2) electromagnetic wavelengths between 375 and 560 nanometers.
  • Orthotropic
    Having three mutually perpendicular planes of elastic symmetry.
  • OSHA
    Acceptable acronym for the Occupational Safety and Health Administration of the US Department of Labor or Occupational Safety and Health Act.
  • Ostwald system
    A method of color notation based on a central gray scale surrounded by solid colors in horizontal and vertical rows.
  • Outdoor board (ODB)
    A weatherproof board or paper used for outdoor advertising signs and displays.
  • Outdoor durability (exterior exposure resistance)
    The ability of a printed product to resist change during exposure to outdoor environmental influences; also refer to weatherability.
  • Outgassing
    The release of vapors from polycarbonate sheet, resulting in bubbles forming between the sheet surface and applied vinyl film or ink film.
  • Outline halftone
    A photograph shot as a halftone with an outline mask to eliminate the background.
  • Outline positive
    A film positive with all areas except the desired subject having all detail eliminated, usually by opaquing the undesired portions on the negative, produces a stencil that does not print areas beyond the outline.
  • Outlining
    (1) A photographic technique of converting solid letters to outline letters; (2) Scribing or drawing the shape of an object as in tracing with a thin line.
  • Oven dry
    A condition when paper has been dried in an oven at 105 plus or minus 3 degrees Centigrade, until its weight has become constant within 0.1 percent.
  • Overcure
    Undesirable condition where an ink or coating is overexposed to the curing process.
  • Overexposure
    The subjection of photosensitive material to light source for a longer period than is necessary to accomplish the desired result.
  • Overfiring
    Heating to a temperature that causes deformation, bending, or discoloration.
  • Overglaze
    Complex compound of lead borosilicates and alkali borosilicates that is applied over previously fired glaze and then refired.