The PRINTING United Alliance Glossary serves as an excellent industry terminology resource. It is the language by which we all communicate. Without it, universal understanding would be impossible.

To keep our constituents well informed about changes to the increasingly complex industry terminology, PRINTING United Alliance has developed this glossary of terms. 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.
  • Clipping
    The grouping (usually unwanted) of all tones or colors above or below a certain value into one composite tone.
  • Clogging
    (1) Premature drying of ink in the screen mesh that blocks portions of the stencil; (2) A restriction of the passage of a material through application equipment.
  • Cloning
    Retouching function on a color imaging system used to remove image defects by replacing pixels in the defective area with duplicate pixels from adjacent non-defective areas.
  • Close tolerance printing (precision printing)
    Screen printing with extreme precision in relation to dimensions and/or placement of design elements, as in electronic circuits.
  • Closeness of control
    Total variation from a desired set point; also referred to as amplitude of deviation.
  • CLUT (Color Look-Up Table) (LUT)
    A color-management software reference file that maintains the proper calibration of devices, such as monitors, printers and scanners. 
  • CMC
    Acceptable abbreviation for the Society of Dyes and Colourists in Great Britain.
  • CMY (Cyan, Magenta, Yellow)
    The three subtractive primary colors used in color negative printing, and some output devices, to produce a full gamut of color.
  • CMYK
    Acceptable acronym for cyan, magenta, yellow, black.
  • CN
    Acceptable acronym for cellulose nitrate.
  • Coagulation
    The transition of a coating material from colloid to the solid state through precipitation.
  • Coalescence
    The joining or unifying of liquid films or adhesives.
  • Coalition of Northern Governors (US)
    Proposed and enacted regulations adopted by many states that limits lead, mercury, cadmium, and hexavalent chromium to 100ppm total in packaging materials and printing inks.
  • Coarse mesh
    Screen printing mesh with low mesh count and large openings or apertures between the woven threads or strands.
  • Coated cloth
    Fabric which has been back coated with rubber or plastic to impart moisture resistance and longer wear.
  • Coated lens
    A camera lens that has been coated with an ultra-thin film, usually bluish in color to minimize glare or flare from extraneous lights not a color correction method.
  • Coated paper
    Paper with a very thin clay coating on one or both sides of the sheet (C1S/C2S) with a finish ranging from eggshell to glossy.
  • Coated screen
    A printing screen with direct emulsion applied to the mesh prior to exposing.
  • Coating
    (1) An unbroken clear film applied to a substrate in layers to protect and seal it or to make it glossy; (2) A screen printed material, pigmented or clear; applied to a substrate and forming a continuous film.
  • Coating mottle
    A small variation in gloss that can be detected on a coated, calendered sheet by viewing the sheet at an angle to check for specular reflection from the surface.
  • Coating pigments
    Mineral materials used for coating paper stock such as clay, (the most common), talc, calcium carbonate, titanium dioxide, and zinc oxide.
  • Coating screen
    A printing screen designed to print a solid layer of clear varnish or ink over a large predetermined area, usually used for applying color to backgrounds of displays or similar uses.
  • Coating weight
    The mass of an applied coating per square unit of surface area sometimes referred to as mass weight.
  • Cobalt drier
    A liquid material containing chemically combined cobalt, used to accelerate oxidation and polymerization of an ink film, promotes drying.
  • Cobb test
    A method used to measure the water absorption of seized paper by determining the weight of water absorbed through one surface under pressure.