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Specialty Graphic Imaging Association
SGIA Glossary

Definition Glossary

Sixth Edition

Language and our ideas about how it is interpreted change rapidly. The Specialty Graphic Imaging Association (SGIA) is aware of this and continues its effort to keep our constituents well informed about changes to the increasingly complex industry terminology. This publication represents the most recent changes.

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A graphic or picture that is embedded in a document file using object linking and embedding (OLE).

object color

The aspect of the appearance of an object dependent upon the spectral composition of the incident light, the spectral reflectance or transmittance of the object, and the spectral response of an observer.

object linking and embedding (OLE)

A standard method for inserting an object into a document, where the document retains a connection or link with its original program.

object oriented

A graphic image that is created with mathematical descriptions instead of pixels.


The ability of an opaque overprint to hide completely the color underneath; also sometimes referred to as obliterating power.


Glass that has been made translucent by grinding, sandblasting, or acid etching.


A natural glass that is produced by volcanic action.

occupational exposure limit (OEL)

Minimum allowable concentration of toxic substances in workroom air to protect workers who are exposed to toxic substances over a working lifetime.


A naturally occurring yellow iron oxide used as a pigment in ink formulations.

OCR ink

Ink that is composed of low reflectance pigments such as carbon black that can be read by OCR equipment.


Outside dimension of an item.


Acceptable acronym for ozone depleting chemical or compound.

off color

Color variation from a sample or specification.

off contact distance

The space between the bottom of the screen and the top of the substrate; also refer to snap-off.

off contact printing

Screen printing with the print screen adjusted slightly above the substrate so that it does not make contact with the substrate except during printing.

off square

A material where two or more corners deviate from an exact 90° angle.

offset (offsetting)

(1) An indirect printing form; (2) The unintentional transfer of ink to the bottom of the printing screen, the back of a succeeding sheet, or other undesired surface.

offset paper

A grade of paper manufactured in a range of weights in white or light colors with good dimensional stability, cleanliness, and pick resistance; alterative term for uncoated book paper.

offset printing

Planographic printing by indirect image transfer.

offset stock

Paper manufactured to accept offset printing ink; also referred to as offset paper and uncoated book paper.


A distortion of an image using an S-shaped curve as one baseline, gives image a wavy look.


Unit of electrical resistance used for measuring or testing the capacity of resistance; the unit of resistance equivalent to the resistance of a conductor in which one volt produces a current of one ampere.


An instrument used for measuring electrical resistance in ohms.

ohms per square

A means of evaluating the resistance value of an ink mixture, or the resistance value of a square of ink one mil thick.

Ohm’s Law

The current in a circuit is directly proportional to the voltage E, and inversely proportional to the resistance R: E=IR, I=E/R. R=E/I.

oil absorption

The quantity of oil required to completely wet a definite weight of a given pigment, forming a paste.

oil soluble resin

A resin that will dissolve in a drying oil at slightly elevated temperature to yield an homogenous film.

oil-in-water emulsion

An emulsion that has water as the external phase and an oil as the internal phase.


A drying oil used in ink formulations made from seeds of licahia rigida tree; similar in properties to tung oil.


Acceptable acronym for on-the-job.

OK sheet

A press sheet that closely matches the original proof and has been approved by the customer, used as a guide to judge print quality as production run progresses.


A chemical family of unsaturated hydrocarbons; also refer to polyolefin.

oleo resinous

Describes solvents or inks derived from crude oil, or having vehicles compounded from crude oil derivatives.


Oil receptive.


Oil repellent.