shrink glossary

• Angel hair - Thin strands of film appearing at the cut end of film resulting from sealing.
• Ballooning - A pillow effect created when air is trapped within the shrinking bag.
• Bead Seal - A thin round weld created when pressure and heat are applied to two layers of film.
• Bi-Axial Orientation - Oriented along both X and Y-axis.
• Blocking - A condition in which two layers of film adhere to one another.
• Blown Film - A film extruded by air inflation. Ex: blown stretch film such as: blown hand stretch film
• Burn Through - A temperature or condition where a film becomes cloudy or burns in the shrink tunnel.
• Centerfold Film - A film that has been folded in half, lengthwise.
• Centerfolder - A mechanical device used to create centerfolded film.
• Coextrusion - Two or more polymers extruded and combined in a die, each forming a distinct layer in the final film.
• Cold Slip - The amount of force required to slide two surfaces against one another at ambient temperature.
• Cold Flex (CF) - Ability of a film to perform at low temperatures without failure.
• Copolymer - Result of two monomers being combined through polymerization.
• Core - A paper tube on which film is wound.
• Cross-Linking - A process which binds the polymer chains into a network. Significantly increasing a films heat stability and strength.
• Crow's Feet - A series of wrinkles radiating out from a finished package's corners.
• Dog-Ears - Triangular projections of unshrunk film at the corners of finished packages.
• Drape - The softness of a film characterized by the ability to conform to irregular shapes.
• Electron Beam - A device used in the cross-linking process.
• Fish Eyes - A scalloped surface on a finished product surface.
• Form-Fill-Seal - A type of equipment which produces a tube of film into which packages are introduced.
• Gauge - A term used to describe the thickness of a material such as shrink film / shrink wrap or stretch film / stretch wrap or pallet wrap ex: 100 gauge shrink film, 60 gauge stretch film, 70 gauge pallet wrap.
• Hole Punch - A mechanical device used to produce an air evacuation hole.
• Hot Slip - The amount of force required to side two surfaces of heated film against on another.
• Impulse Seal - A heat sealing technique where the element is pulsed with voltage during the sealing cycle.
• L-Sealer - A term used to describe equipment where the seal area is in the shape of a "L".
• Laminate - A general term used to describe structures comprised of two or more materials.
• Lap Seal - A seal made with two layers of film overlapping one another.
• Machinability - The ability to form and seal on overwrapping equipment.
• Machine Direction (MD) - The direction the film is manufactured and moves through the sealing equipment.
• Memory - The ability of a film to maintain its characteristics after shrinking.
• Monoaxial - A film which is oriented to shrink in only one direction.
• Monolayer Film - A single layer film extruded from one or a blend of raw materials.
• Mutilayer Film - A film comprised of more than one layer of similar or different polymers.
• Opaque - Relatively impervious to light. Ex: opaque white stretch film, opaque black stretch film (stretch wrap)
• Optics - The visual properties of a film. Examples of shrink film products with good optics include: Exlfilm HSP shrink film - a superior optic shrink film, Exlfilmplus LTF Shrink Film - shrink film has excellent optics & strength, LTG Shrink Film - a light gauge polyolefin shrink film with excellent clarity, gloss and tear resistance and Exlvalue Anti Fog Shrink Film (AF Shrink Film) - a anti fog shrink film providing clear presentation in refigerator and freezer applications.
• Orientation - The stretching technique used in the manufacturing of film.
• Oriented - The stretching and aligning of a film's molecules at a temperature below its melting point.
• Perforations - Air evacuation holes in a film made by pin perforators.
• Pin Perforators - A device used to produce small holes in film to allow air to escape during the shrinking process.
• Polyethylene - A simple thermoplastic polymer of ethylene.
• Polymer - A material made through the process of polymerization.
• Polymerization - A gas heated under pressure forms a solid.
• Polyolefin - A generic term used to describe ethylene and/or propylene based plastics. Also see polyolefin shrink film and shrink film packaging products
• Polypropylene - A thermoplastic polymer of propylene.
• Preferential Shrink - The characteristics of a film to shrink more or less in a specific direction.
• PVC - Polyvinyl Chloride. Also a type of shrink film.
• Seal Wire - An element made from nichrome wire used to seal film.
• Selvage - Another term for trim waste.
• Shrink - Defined as the ability to become smaller.
• Shrink Tunnel - A type of equipment featuring a chamber producing heat and airflow designed to shrink film.
• Singlewound Film (SW)- A single layer of shrink film wrapped around a core.
• Slip - The quality of a film to move over surfaces with little resistance.
• Static - An electrical charge built-up in plastic film.
• Static Seal - A type of longitudinal seal used in FFS equipment. Overlapping film edges are adhered to one another via a static charge.
• Tap Switch - An electrical device used to control the amount of voltage introduced to sealing elements.
• Tear Initiation - The amount of force required to initiate a tear.
• Tear Resistance - The ability of a film to resist the propagation of a tear.
• Transverse Direction (TD) - The direction parallel to the film width.
• Trim - The amount of excess film severed during the sealing process.
• Trim Seal - A seal made by using a sealing wire element.
• Unbalanced - Unequal orientation in the LD and TD.
• Wind - The direction in which the film or shrink film is wound on the core.

Shrink wrap related links:

• Shrink Wrap 101 - Shrink Wrap Resource Guide for Shrink Film Buyers
• Shrink Film Packaging - Polyolefin Shrink Film Packaging Solutions
• Clearance ShrinkWrap - Quality Shrink Wrap Supply - Great Value
• Shrink Wrap Machines - Packaging Equipment distributor offering shrink wrap packaging systems, shrink wrap tunnels, shrink wrap machines and more.