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.
  • Scanner
    A hardware peripheral that illuminates, reads, and converts original information into digital data.
  • Scarf
    A joint formed by stripping or bolting two notched pieces together.
  • Scatter diagram
    An x-y chart that measures the relationship between two sets of variables.
  • Scattering
    The process by which light passing through a material is redirected in many directions.
  • Scattering coefficient
    Rate of increase of reflection over an ideally black backing, caused by the internal scatter of light in the surface of the paper that is not completely opaque.
  • Scavenging
    In the printing of solder paste through etched metal masks, this occurs where the flexible squeegee blade presses down into the open stencil cavity, with the result of scraping solder paste out of the stencil rather than depositing the desired thickness onto the substrate.
  • Scleroscope
    A device to measure Shore hardness consisting of a small conical hammer fitted with a diamond point and acting in a glass tube. The hammer strikes the material and the degree of rebound is noted on a graduated scale.
  • Scoop coater (coater)
    A tool for coating screen printing mesh with liquid photosensitive emulsion; a tool typically a scrapper with a smooth metal trough used to spread thin layers of direct emulsion on a prestretched mesh.
  • Scoop coater (emulsion coater) (coater)
    A tool for coating screen printing mesh with liquid photosensitive emulsion; a tool typically a scrapper with a smooth metal trough used to spread thin layers of direct emulsion on a pre-stretched mesh.
  • Scotchlite?
    Trade name of the 3M Company for a reflective sheet material used for outdoor applications.
  • Scratch test
    A ink adhesion test that involves placing a printed sample on a hard, smooth surface and scratching it with a fingernail using quite heavy pressure to determine if the ink imprint will flake off the surface.
  • Screen
    (1) An assembly of stretched screen printing mesh on a frame with stencil attached, ready for printing; (2) A transparent glass sheet placed before the camera film when photographing continuous tone art to produce dot structure of the design; another type is produced photographically on film with vignette dots which is placed in contact with the film.
  • Screen angle(s)
    The coordinated placement of multicolor halftone screens, with respect to all others in the same printing group, to avoid moiré patterns.
  • Screen carriage
    The mechanism that holds the screen in the printing device. screen cutting the wear and/or cutting from the substrate side of the screen mesh or stencil by rough or sharp substrate edges.
  • Screen distance
    The distance a halftone screen is set in front of the ground glass in a process camera to bring the dot structure into proper focus.
  • Screen frequency
    The number of lines or dots per centimeter or inch on a half tone screen.
  • Screen gauge
    A device for determining the screen ruling used in a printed halftone negative or positive.
  • Screen holder (frame clamp)
    The fittings or clamps where a screen printing frame is attached to a screen printing press or manual screen printing unit.
  • Screen ink
    A printing ink, usually quick drying, full bodied and specifically formulated for screen printing.
  • Screen knuckle
    The area of overlap in woven screen mesh.
  • Screen mesh (screen fabric)
    (1) A woven material of synthetic polyester, nylon fiber, or finely drawn wire; (2) A woven mesh material used to hold the stencil in screen printing.
  • Screen opener
    A chemical, usually aerosol that is used to dissolve ink that has clogged the open areas of the stencil.
  • Screen printing
    A through printing (& contact printing) process where an ink passes through patterned openings (applied to a woven mesh held under tension) onto a substrate.
  • Screen printing plate (printing screen, image carrier)
    A frame or supporting device onto which is stretched and attached a mesh having open space in the areas of the mesh representing a design to be printed.
  • Screen process printing
    An obsolete term, now referred to as screen printing.