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.
  • Proxy
    A representative version or sample of a larger image.
  • Proxy image
    A low resolution image used in any software program to show the effects of change without performing transformations on high resolution files.
  • PSA primer
    Preliminary coating applied to a surface to enable an adhesive system to bond to a substrate.
  • Pseudoplastic
    Material where the viscosity decreases with increasing shear rate, such as polymer solutions and emulsions, coating dispersions, paints, adhesives, varnishes and resins.
  • Psid
    Pounds per square inch differential; a pressure difference between two points.
  • Psig
    Pounds per square inch gage; pressure referenced to ambient air pressure.
  • Psychrometer
    A type of hygrometer, that uses the difference in readings between two thermometers, one having a wet bulb ventilated to cause evaporation and the other having a dry bulb as a measure of atmospheric moisture.
  • PTA
    Acceptable abbreviation used to describe a pigment that has been precipitated with phosphotungstic acid to give it permanence and insolubility.
  • PTF
    Acceptable acronym for polymer thick film.
  • Puckering
    Gathering of fabric due to its tension being less than that of the stitches.
  • Puddle method
    A method of developing stencils without complete immersion in the developer.
  • Puff ink
    An ink that when heated to a specific temperature for a definite period of time, achieves a characteristics of three-dimensionality by expansion.
  • Pull compensation
    Deliberate distortion digitized into the design to allow for thread pull that would otherwise cause a one centimeter stitch to shrink to point nine centimeters due to thread tension.
  • Pulp
    Primary raw material from groundwood, semi-chemical wood, chemical wood (sulfite and sulfate) and cotton from which paper is made.
  • Pulp type papers
    Those papers containing ground woods, sulfate and/or sulfate pulps exhibiting characteristics of high opacity and high strength.
  • Pulsed xenon (flash xenon)
    A type of actinic illuminate (xenon gas) that provides a very constant output with a spectral composition resembling sunlight.
  • Punched out label
    Labels that have been die cut through both the face and backing sheet or liner.
  • Punching
    Changing a visual design into an electronic record to drive an automated embroidery machine.
  • Purity of color
    A color in relation to its composition of pure pigments that form the hue and its lack of inerts, fillers, bulking agents, and other additives.
  • Push-in lock
    A simple, sturdy lock consisting of a predetermined segment of the display stock so that it can be pushed into position to hold an assembly in position.
  • PVA
    Acceptable acronym for polyvinyl acetate solution used in direct-emulsion stencils.
  • PVC stock
    Plastic sheet materials made from polyvinyl chloride.
  • PWB
    Acceptable acronym for printed wiring board.
  • Pyramid shadow box
    A shadow box for displays requiring a strong tilt back.
  • Pyrocon
    An instrument used for determining the temperature of the heating plate on a heat transfer machine.