Glossary Of Terms

The SGIA 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. SGIA 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 SGIA assumes no responsibility for the use of information presented herein.


  • Anvil cut label
    Pressure sensitive label that have been die cut through components of the label stock.
  • Aperture
    (1) The open area in screen printing mesh between the threads; (2) Opening in a camera lens through which light rays pass from subject to film plane to form an image.
  • Aperture percentage (mesh opening area) (percentage open area) (open area)
    The percentage of the total area of a web of screen printing mesh that is not occupied by the threads of the weave; i.e., that portion of the fabric area through which ink can pass.
  • Apochromatic lens
    A process lens that has been corrected for both chromatic and spherical aberrations.
  • Apparent dot area
    Percentage of dot coverage in a specific area, as measured using a densitometer and calculated using the Murray-Davies equation.
  • Apparent dot gain
    Difference between the apparent dot area of the film, as measured by a transmission densitometer, and the apparent dot area of the proof or printed sheet, as measured with a reflection densitometer. (Indicates how much the dots of ink have spread in relation to the original film dot area).
  • Apparent viscosity
    A characteristic of multi-component liquids that have a variable ratio of shreds stress over shear rate (variable viscosity depending on conditions).
  • Appearance
    Manifestation of the nature of objects and materials through visual attributes such as size, shape, color, texture, gloss, transparency, and opacity.
  • Application
    (1) An adhesive-coated film emblem, or decal affixed to a designated substrate; (2) An ink or color screen printed directly onto a substrate; (3) Often used as a general term to designate a particular screen printed product; (4) The highest level of software that a user sees; also a generic term for software.
  • Application printing (textile)
    The placement of coloring agents directly onto the fabric substrate.
  • Application tape (application paper)
    A support material used to facilitate the application of pressure sensitive markings.
  • Application temperature
    The minimum temperature at which a pressure sensitive material can be applied to a surface.
  • Applicator
    An instrument or equipment for applying something such as a device that automatically feeds and applies labels to the product.
  • Applied color decorating
    Decorating by applying color directly onto the substrate, as opposed to using transfer or decal techniques.
  • Apron
    Extension area of lehr for handling of ware, also be applied to extensions of conveyor dryer for stock handling.
  • Aqueous dispersion
    Pigments dispersed in a water soluble binding medium that changes to a water insoluble form when the printed cloth is steamed or heat cured.
  • Arc resistance
    The resistance to current flow across the surface of the material measured as the time required for an arc to establish a conductive path in a substance.
  • Archival
    Term loosely used to refer to material that can be used without side effects in the conservation or care of important artifacts. Pertaining to the production of new items designed to have very good aging qualities. e.g. non-fading inks, acid free paper, etc.
  • Archival ink
    Ink used in fine art digital printing that has been optimized for permanence.
  • Archiving
    Retention of images, often on CD-ROM, for a specified period. Information necessary to reproduce the print is also archived, including ink, tables, sizes, and media used.
  • Arcing
    A spark discharge of electric current crossing a gap between two electrodes.
  • Argon
    A colorless, odorless inert gas.
  • Aromatic solvent
    Organic liquid derived from products of petroleum origin having a cyclic or ring hydrocarbon structure and KB (Kauri Butanol) value over 40 such as toluene or xylene.
  • Art knife
    A tool with an usually small, keen blade used for very light cutting of sheet material such as frisket paper, masking film, tracing sheet, and other such materials.
  • Art paper
    A coated paper often having a high finish used in printing halftones.