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.


  • Cobwebbing (angel hair)
    Fine filaments or strings resembling cobwebs that project at random from the edge of the ink or coating on the substrate.
  • Cockle
    (1) An irregular lump in a fabric thread; (2) A desirable paper finish in cotton fiber sheets produced by air drying paper with controlled tension.
  • Cockling
    An undesirable effect in paper identified by the uneven, rippled appearance of the paper surface caused by improper drying.
  • Coefficient of thermal expansion - linear
    (1) The fractional part of its length that a material elongates when raised one degree Celsius in temperature; (2) Fractional change in length or volume of a material divided by the change in temperature.
  • Cohesion
    (1) Mutual attraction of elements that bind the particles of an ink or varnish film together; (2) The ability of an adhesive to resist splitting; (3) The forces holding a single substance together.
  • Cohesive failure
    The rupture of an adhesive bond such that the separation appears to be within the adhesive.
  • Cohesive strength (cohesion) (internal bond)
    The internal strength of an ink or adhesive, due to the mutual Attraction force between like molecules.
  • Cold color
    (1) An organic enamel for glass decorating that is baked at a low temperature, usually under 260 degrees C (500 degrees F); (2) A bluish or greenish hue.
  • Cold cracking
    Deterioration of a plastic from cold temperatures causing stiffness and even brittleness, breaking or shattering under stress as temperature is lowered.
  • Cold curing
    The process of curing at normal atmospheric temperature.
  • Cold end
    Packing end of a lehr or intake end of conveyor dryer where heat is used to aid drying.
  • Cold flow (ooze)
    The viscous flow of a pressure sensitive adhesive under pressure or other stress, at room temperature; also refer to creep.
  • Cold peel
    Process where the release paper of a plastisol transfer is not removed until the heat of application has dissipated.
  • Cold setting ink
    Solid ink that is melted and applied as a liquid through a heated printing screen, solidifying again on contact with the substrate that is not heated.
  • Cold temperature adhesive
    An adhesive that will induce a bond to a cold substrate.
  • Cold weather adhesive
    An adhesive formulated to be usable at 0 degrees C (32 degrees F) or other specified low temperature.
  • Cold-cathode lamp
    A low pressure UV germicidal lamp, refer to germicidal lamp.
  • Collapsible channel
    A display part that forms a channel for setting up but collapses flat for shipping.
  • Collapsible shadow box
    A shadow box with top, bottom, and collapsible apron.
  • Collate
    The gathering of printed sheets into an organized sequence.
  • Collective mark
    A distinctive mark or symbol identifying an association, fraternal society, or membership in a trade union such as SGIA, SME, ASI, and AFL/CIO.
  • Collodion film paper
    A backing paper coated with a water soluble film used in ceramic decal production, where screen printing is done on the surface of the collodion film.
  • Collodion process
    A method of photography where a glass plate is coated with salted (iodized) negative collodion and sensitized by immersion in an acidified silver nitrate solution and exposed in a moist condition.
  • Colloid
    Water-soluble, non-crystalline substances such as gelatin, glue, or albumen, of very fine granule size, used as vehicles in photomechanical sensitizers in screen printing and made light-sensitive by the addition of a bichromate.
  • Colloid mill
    A machine used for the dispersion of pigments that produces intense shearing stress in the liquid to which the solid pigments have been added, used in ink manufacturing.