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.
  • Black printer (K)
    In process color reproduction, the prepress materials used to produce the black image. (The letter "K" is used to designate this color.)
  • Blackboard coating (chalkboard coating)
    A smooth, hard, Matte surface coating applied by spraying or screen printing onto a substrate to provide a writing surface for chalk.
  • Blackbody
    A surface that completely absorbs all radiant energy striking it without reflection.
  • Blackening
    A darkened defect in paper caused by crushing at the calendars which is usually associated with a decrease in capacity, but may also be caused by excessive moisture.
  • Blade
    The flexible printing edge of the squeegee which may be made from various elastomers of polyurethane, neoprene, or rubber.
  • Blade coating
    A method of coating paper utilizing a flexible blade set at an adjustable angle against the web, supported by a soft surfaced backing roll.
  • Blade marks
    Broad indentations in the surface coating of paper, which can be caused by an untrue blade or faulty mix of the coating material.
  • Blade scratch
    A very fine hair-like indentation in paper which may vary from a few feet to several hundred feet in the machine direction of the web.
  • Blank dummy (mock-up)
    A full size, serviceable model of a display without printing or art work.
  • Blank ware
    Undecorated glass or ceramic ware.
  • Blanks
    (1) Cardboard, plastic, metal, or other unprinted substrate used for making displays and signs; (2) Unprinted garments or piece goods.
  • Bleach
    (1) Method of measuring the tinctorial strength of an ink or toner; (2) Generic for household bleaching agent such as Clorox®, sometimes used for reclaiming printing screens.
  • Bleach board
    A paper boards that is totally composed of bleached fiber.
  • Bleaching
    The removal of color or other material by chemical action.
  • Bleed
    (1) The spreading or migration of an ink component or dye into an area where it is not wanted; (2) The spreading or running of a pigment color by action of a solvent; (3) Color printed to or beyond the finished outer edges of a substrate; (4) The part of the page that is trimmed off, referred to as selvage.
  • Bleeding
    (1) The diffusion or migration of color from an ink film to the surrounding surface, with which it comes in contact; (2) Migration of dye from a fabric to the ink or coating previously applied, usually initiated by heat.
  • Blend
    (1) The content of the fabric sometimes used in the manufacture of a garment such as 50% cotton and 50% polyester; (2) Printing two colors so smoothly that there is no perceptible line at their intersection; (3) A mixture of solvents, resins, and/or pigments; (4) Inter-mixture of two or more colors; (5) In computer graphic software, the intermediate steps between two objects created when the objects are merged together via a specified number of intermediate steps.
  • Blending
    (1) Intermix of two or more solvents and/or pigments; (2) Arrangement of colors, and act of printing by intermixing various colors on the screen to provide an even gradation from one intensity to the next without using photomechanical techniques.
  • Blind embossing
    Impressing a relief image into a substrate without first printing the image.
  • Blister (blistering)
    (1) A defect consisting of a bubble that forms during drying or fusion and remains in the print after drying or firing is complete; (2) A bubble entrapped in a glass or ceramic article.
  • Block out
    Sealing the mesh of the printing screen against pinholes and leakage in the areas between the image and the extreme edges of the frame.
  • Blocking
    An undesired adhesion between layers of material placed in contact under moderate pressure and/or temperature in storage or use, usually occurs in a stack of printed material that is stacked prior to thorough drying.
  • Blockout solution (blockout compound) (blockout filler)
    Liquid masking material used to cover pinholes and non-image areas of the screen mesh around the perimeter of the stencil.
  • Bloom
    (1) The bluish-gray milky veil that appears on the surface of a print under adverse conditions of heat and humidity; (2) A film that forms on glass enamel or precious metal as a result of atmospheric action during firing.
  • Blotch
    An area of discoloration, usually irregular in shape.