Glossary of Terms
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Adhesion, Peel
The force required to remove a pressure sensitive label from a standard test panel at a specified angle and speed after the label has been applied to the test panel under specified conditions.

Adhesive
A substance capable of holding materials together by surface attachment. Adhesive, Bleed Adhesive exudation from pressure sensitive label stock and labels.

Adhesive. Cold Temperature
An Adhesive that will enable a pressure sensitive label to adhere or stick well when applied to a cold substrate.

Adhesive, High Temperature
An adhesive that will enable a pressure sensitive label to adhere or stick well when applied to a hot substrate.

Adhesive, Permanent
An adhesive characterized by having relatively high ultimate adhesion.

Adhesive, Pressure Sensitive
A type of adhesive which in semi liquid form is aggressively and permanently tacky at room temperature and firmly adheres to a variety of dissimilar surfaces upon mere contact, without the need of more than finger or hand pressure.

Adhesive, Removable
A pressure sensitive adhesive characterized by relatively high cohesive strength and low ultimate adhesion.

Basis Weight
The weight in pounds of a ream (480 or 500 sheets) of paper cut to a given size.

Break
A term used to denote a tear in a roll of face material or release liner. Such defects are generally spliced and marked by a protruding flag.

Butt Cut Label
The face material is die cut all the way across the width of paper, there is no waste between labels.

Butt Cutter
A rotary tool with blades that cut through the face stock of a paper material and not cut through the release liner. The blade extends the length of the tool from bearer to bearer.

Caliper
The thickness (as of a sheet of paper) measured under specified conditions. It is usually expressed in thousands of an inch (mils).

Delamination
The separation of a material into layers in a direction approximately parallel to the surface.

Die
Any of various tools or devices used for imparting or cutting a desired shape, form or finish to or from a material.

Die Cut
1) To cut labels with a die.
2) The line of severance between a pressure sensitive label and its matrix or adjoining label made by cutting edge of a die.

Dispenser
A device that feeds pressure sensitive labels, either manually or automatically, in convenient units. It often serves as a package for the labels as well.

Embossed
A term applied to the face material of pressure sensitive labels that has printing or a design in raised relief.

Face Material
Any paper, film, fabric, laminated or foil material suitable for converting into pressure sensitive label stock.

Feathering
A defect which is characterized by ragged, course edges in print.

Feel
A term used to express the impression obtained by handling cloth and paper to judge its finish and general quality.

Finish
The surface property of a paper sheet determined by its surface contour and gloss.

Flagging
The spontaneous lifting of the edges of a pressure sensitive label from a surface.

Flexibility
A property of face materials, measured under specified conditions, that indicates how readily they will conform to curved surfaces (i.e. Flex stock).

Flexographic Printing
A method of rotary printing that employs flexible rubber plates or photopolymer plates and rapid drying inks (also known as Flexo Printing).

Fluorescent Paper
A paper that is coated with a fluorescent pigment which not only reflects a visible wavelength, but is activated by most of the remaining absorbed light to re-emit it as a color of a longer wavelength which results in reinforcement of the reflected color.

Gear Size
Number of gear teeth on printing cylinder or rotary tool.

Horizontal Cavity
Space between labels running perpendicular to the web direction (across).

Horizontal Perforation
A perforation made in the release liner and/or face material across the web direction (stripped and perforated label).

Kiss Impression
The minimum pressure at which proper ink transfer is possible between plate and paper in letterpress and flexographic printing.

Label
A slip of any material that can be affixed to a substrate to indicate ownership, contents, directions, destination, rating, etc.

Label, Face Cut
A die cut label product from which the matrix has not been removed.

Label, Fan Folded
Pressure sensitive labels that are in a continuous form but are fan folded rather than rolled.

Label, Pressure Sensitive
A die-cut part that has been converted through roll fed production equipment utilizing the type of pressure sensitive material which has a protective backing; the end product is produced in the form of either rolls, sheets, fan fold, or by other techniques that produce like products which have been slit or cut from the converted roll.

Label, Roll
Pressure sensitive labels that are packaged in a continuous roll form.

Label, Sheet
Pressure sensitive labels that are packaged in sheets.

Label Stock, Pressure Sensitive
The combination of face material, anchor coat, pressure sensitive adhesive and release liner from which pressure sensitive labels are manufactured.

Lift Tab
A vertical cut made in the face stock but not through the release liner of a butt cut label. The face material is then removed so that the label may be easily removed from the release liner upon application.

Liner, Release
The component of the pressure sensitive label stock which functions as a carrier for the pressure sensitive label. Prior to application, it protects the adhesive, and readily separates from the label immediately before the label is applied to its substrate.

Matrix
The pressure sensitive face material surrounding a pressure sensitive label which is usually removed after die cutting thereby leaving laid-on labels on the release liner.

Matte Finish
A dull finish on paper stock.

Number Around the Cylinder
Number of each imprint on a plate around the printing cylinder in Flexo printing.

Number Up (Across the Web)
Quantity of labels being run on the width of the face stock (perpendicular to the web direction).

Pantone Matching System (PMS)
Book that has numbered samples of inks in different shades for each color. It assigns a number and tells how to mix ink to match each shade.

Pattern Coating
Refers to the width and spacing arrangements of strips of adhesive laid down parallel to machine direction on pressure sensitive label stock during its manufacture. Often directed to the adhesive pattern carried by pressure sensitive labels made from such material (i.e. Patterned adhesive is used for Patient Charge Labels).

Perforated
Refers to a series of small incisions made in laid on labels and/or their release liner to facilitate tearing along a predetermined line. There consists a series of cuts and ties or holds within an area that is perforated. The cuts are the areas where the perforator blade goes through the paper stock and/or release liner the tie or hold is the area not cut by the perforator blade.

Perforator
A rotary tool that has perforated blades which cut through the face stock and release liner which is known as metal to metal cutting. The metal perforator blade cuts through down to the metal base roller under the paper stock.

Pin Fed
Series of circular feed slots 1/2" apart punched in margins of pressure sensitive label stock for indexing forms to be fed through Electronic Data Processing equipment. These must be run on an exact spacing Webtron Press (1/8 Circular Pitch) or New Era letterpress.

Plate (print) Cylinder
That cylinder on a Webtron Press to which the photopolymer plate is attached.

Radius Rectangle Die
A rotary tool which has a certain size blade cavity shape that can cut through the face stock of a pressure sensitive paper material and not cut through the release liner.

Register
The exact corresponding placement of successively printed images and/or successively die-cut pressure sensitive labels.

Removable Blade Die
A rotary tool with blades that can be taken out to change depth size of cuts. This is a metal to metal cutting tool used primarily for sheeting individuals off the press and can be used as a perforator, if perforated blades are placed in the tool.

Removability
A relative term applied to pressure sensitive labels to describe the force or condition under which they can be removed from a substrate.

Repeat
Distance from top of one label to top of next label running parallel to the web direction; includes depth or step size of label added to vertical cavity between labels. If there is no vertical cavity between labels as in the case of a butt cut label then the repeat and step size would be the same.

Score
A vertical cut made in the face material and not the release liner of a pressure sensitive material.

Self Adhesive Products
Converted pressure sensitive labels and products protected by a release liner. Term used to differentiate from selfwound products such as pressure sensitive tapes.

Smudge Resistance
The resistance of a freshly printed paper surface to ink blurring or smearing.

Split Back
Slit(s) in the release liner to facilitate its removal by hand used mainly for individual labels. (i.e. Flo Meters)

Step Size or Depth
Dimension of label running parallel to the web direction.

Stripped and Perforated Label
Paper stock that has been die cut into a particular shape down to the release liner. The waste matrix is then removed and there is a perforation made in the release liner between the labels.

Tack
That property of a pressure sensitive label which causes it to adhere to a surface instantly without external pressure for better contact.

Tint
A random color placed over the entire width of the face material.

Varnish
A solution or suspension of one or more materials in a liquid vehicle capable of forming a protective and/or decorative film as the vehicle dries by oxidation.

Vertical Cavity
Space between labels running parallel to the web direction (down).

Vertical Perforation
Perforation running down the web through the release liner and on face material.

Web
A continuous sheet of pliable manufactured material.

Width
Dimension of label running perpendicular to the web direction.