Light Fab's Converting and Fabricating Glossary of Terms:

Acrylic Adhesive: These adhesives usually have high temperature resistance, high-grade UV resistance and great permanent bond strength.

Adhere: To bond; to cause two surfaces to be held together by adhesion.

Adhesion: Level of attraction between any adhesive and the surface it is bonded with. Surface energy of the material determines the strength of the attraction.

Back Split: Process where the fabricator slits the release liner for easy removal from the PSA by hand.

Baloney Slitting: The common method of slitting pressure sensitive tapes, producing rolls per step or per cycle. Also referred to as lathe slitting, lever or single-knife cutting. This process features quick-setup and economical per-slit cost.

Buckling: The phenomenon when PSA tape ripples and causes an opening or gaps between layers in the manufacturing process.

Butt-Cutting: Die cutting process where a kiss cut is performed, but no matrix is created. The parts are directly next to each other. Products are usually square or rectangular shaped on a roll or pad.

Butt Splice: A splice made by joining tape end-to-end without a space nor any overlapping. A thin single coated tape centered on both sides usually assembles the splice.

Caliper: Thickness measurement of material expressed in thousands of an inch or millimeters.

Carrier: Double-coated tapes have a thin "carrier" of film to which one or two types of PSA adhesive is coated to each side.

Cross Direction: When referring to roll, web or machine direction, "cross direction" right angles the web to which it runs through a given machine.

Die Cutting: Fabricating process to make any shape or geometric pattern, design, square, rectangle, circle, etc. through the use of steel rule dies, rotary or circular dies, thermal and clicker dies, as well as machined compound and progressive die tooling.

Double-Coated: Tape consisting of a carrier with PSA adhesives coated to both surfaces and usually supplied wound on a silicone release liner.

Fabricator/Converter: One who modifies products to enhance their value and final usage. Products can be modified primarily by:

• Laminating
• Die cutting to a custom shape
• Precision slitting/rewinding
• Spooling/level winding
• Perforating, Scoring
• Adding/removing liners
• Cutting pieces to length

Fish Eyes: Small but visual deformations on the PSA surface caused by the air entrapment between the PSA and the material it is coated on. This is necessarily a quality defect and usually diminishes over time.

Fogging/Ghosting: A fog or haze-like deposit from a PSA to another substrate visible after removal of PSA.

Gapping: When two layers or more of material become separated from each other causing an opening or openings.

Heat Activated: Thermo-plastic adhesive film is usually heated so bonding can be accomplished before it cools back to room temperature.

I.D.: Inside diameter.

Kiss Cutting: Die cutting process where the die strike depth is controlled down to the release liner, but not through it. For example, pressure sensitive labels in roll form. The usable product is left on the roll and the matrix is removed.

Laminating: Joining of two or more layers of materials using pressure-sensitive adhesive products. The process involves nip or compression of the layers, usually through a set of rollers with controlled pressure and speed.

Matrix: The pattern or arrangement of removed material to allow for a pre-spaced concept of die cut parts. Also referred to as the skeleton, weed or waste.

Memory: The willingness of material to return to its original size or shape after being stretched or distorted.

Migration: The process when materials from one substrate slowly move to another substrate. When die cutting soft adhesive the matrix usually needs to be removed before the PSA migrates back and rejoins itself in the areas it was previously cut.

Mils: Regarding thickness of materials, inferring thousands of an inch. For example, 4 mil thick material is actually .004" thick.

O.D.: outside diameter.

Pancake Wound: The typical form of a roll of tape where each layer is directly on top of the next one. Also referred to as planetary wound.

Pattern or Zone Coating: During the manufacturing process many PSA adhesives can be produced or "voided out" in specific "lanes" or zones in the direction of the unwind. Usually done to achieve an extended liner. Converters offer many creative options regarding such with any tape.

Perforating: The process where "skip" cutting material in a particular direction allows the material to tear easily into pieces or strips of a desired length. For example, form-fed printer paper.

Plasticizer: A chemical substance added to plastic, foam, and other substrates to enhance flexibility.

Plasticizer Migration: When Plasticizers are omitted from a substrate and attack the PSA bonded to it. The PSA usually "softens" to the point of bond failure.

Pressure Sensitive: Adhesive tapes that stick to a variety of surfaces with little(hand) pressure applied. These tapes are usually tacky or "sticky" at room temperature and do not need activation by heat, water, or added solvents.

Release coating: Thin coating of material (usually silicone) applied to a release paper or film. Enables PSA to be unwound from itself and/or the PSA to be removed from the release liner for lamination to a substrate.

Rewind Slitting: The method is for producing multiple cuts per cycle. This has a longer set-up time than baloney slitting. The process actually rewinds the material layer by layer across a set of pre-spaced knives and spacers, onto a rewind shaft that is set with pre-slit cores and spacers, with each individual slit roll wound on individual tension-controlled cores.

Scoring: Creasing or bending line that assists subsequent usage. Scoring is also a term used to describe when one or more materials are slit or cut through to assist in the tape application.

Self Wound or Single Wound: Often used in reference to pressure-sensitive tapes when comparing them to linered tapes. Each subsequent layer has the exposed adhesive in direct contact with the backing of the previous layer.

Shear Adhesion: The level of bond strength a PSA has to a substrate when shear force or stress is applied. For example, a PSA used to hang a picture on a wall should have good shear adhesion.

Surface Energy: quantifies the disruption of intermolecular bonds that occurs when a surface is created. Examples:

VERY HIGH Surface Energy (greater than 50 dynes/cm2)

• Stainless Steel
• Aluminum
• Copper
• Tin
• Zinc
• Lead

HIGH Surface Energy (35 to 45 dynes/cm2)

• Alkyd Enamel
• Polycarbonate
• Polyester
• Acrylic
• Melamine
• ABS
• Vinyl
• Nylon
• Kapton

LOW Surface Energy(30 to 35 dynes/cm2)

• Polypropylene
• Polyethylene
• Polystyrene
• Tedlar
• PVA
• EVA
• Acetal

Tolerance: Allowed variation from specified dimensions.

Traverse Wound: Also referred to as level winding, spool wound and reel wound. For example, sewing machine thread or fishing line. This process enables the fabricator to put extremely long lengths of custom slit material on one roll which means less roll changes and cost savings on a manufacturing line.