Features, Glossary & Benefits


Accumulator: In automated packaging operations, a device, a table, or a type of conveyor designed to permit the gathering of packs or objects.

Aerobic: A general term describing those micro-organisms that propagate only in the presence of oxygen

Aerosol: In packaging, a gas-tight, pressure-resistant container, a valve, a product, and a propellant that forces the product from the container when the valve is opened.

Anaerobic: A general term describing those micro-organisms that will propagate in the absence of oxygen.

Aseptic Packaging: A pack and product system in which the product and pack are individually rendered aseptic(sterile) and then combined and sealed under aseptic conditions. In contrast, in a typical canning operation neither can nor food is sterile when they are brought together and sealed. Sterility is achieved by heat-treating the sealed can.


Bar code: A machine-readable symbol.

Barrier: The ability to stop or retard the movement of one substance through another. In packaging, the term is most commonly used to describe the ability of a material to stop or retard the passage of atmospheric gases, water vapour, and volatile flavour and aroma ingredients.

Barrier Material: A flexible packaging material possessing properties that limit the transmission of various gases through the material. ( used to keep products dry, wet or extend shelf life and assure product freshness)

Barrier Packaging: The utilization of engineered materials that possess properties capable of preventing the permeation of harmful substances through material, which would result in product damage.

Biaxial Orientation: A film that has been stretched under certain temperature conditions equally in both the machine and transverse directions.

Blister Packaging: A type of packaging in which the item is secured between a preformed (usually transparent plastic) dome or “bubble” and another surface or “carrier”. Attachment may be by stapling, heat-sealing, gluing, or other means.

Blown Film:  Film produced by extruding resin into a tube, which is expanded by air pressure.

Blown-Film Extrusion: The manufacture of thin plastic films by extruding a bubble of plastic and then inflating the bubble. In film manufacturing the extrusion and inflation are a continuous process.

Burst Strength: A measure of the ability of a sheet to resist rupture when pressure is applied to one of its sides by a specified instrument under specified conditions.


Cast Film: Film extruded through a flat die into a quench system.

Clarity: Degree of transparency

Closure: Any device used to close a bottle, jar, can, pouch or any type of pack to retain the contents. Commonly closures are held in place by a screw thread.

Co-extruded Film: Flexible packaging material consisting of two or more different materials that are layered within a single ply during the extrusion process.

Compatibility: The ability of a container or material to resist chemical degradation or physical change caused by the product, or to chemically change or physically degrade the product contained.

Converter: A manufacturer that takes raw materials and converts them into a usable pack or pack component. Most commonly used in reference to manufacturers of flexible packaging materials. For example, a converter may print a polypropylene film, combine it with foil and polyethylene, and slit it to the widths required by a user.

Core: A paper tube used as a base for forming a roll of film

Corona Treatment: A treatment to alter the surface of plastic and other materials to make them more receptive to adhesives or printing inks. An electrical discharge creates ozone, which in turn oxidizes the substrate surface and creates polar sites that
contribute to strong bond formation.

CPP: Cast PP film, (see PP). Unlike OPP, it is heat sealable, at much higher temperatures than LDPE, thus it is used as a heat seal layer in retortable packaging. It is, however, not as stiff as OPP film.

Cross Direction (CD): The direction at right angles to a material’s flow through a machine. Flow direction through a machine may impart directional properties to a material.


Density: The weight of a given volume of a material. In metric units density is given in kilograms per cubic metre, although in packaging, grams per cubic centimetre is more common. Relative density or specific gravity is the ration of the density of the
observed object to that of water.

Die-cut: Any operation in which a form that incorporates sharp cutting edges is pressed into a substrate to cut out a designed shape.

Doyan: Machine-made tooling that puts in a rounded or curved bottom gusset.


Economic Order Quantity (EOQ):  Beyond the actual cost of manufacture, product cost is affected by the cost of setting up the production line and the cost of storing inventory beyond what can be immediately used. The longer the production run, the lower the setup cost per part. However, inventory costs increase as more products need to be stored beyond immediate needs. EOQ describes the point at which the two costs added together are at a minimum.

Elongation: The percentage a film will deform or stretch prior to breaking.

EVOH: Ethylene Vinyl Alcohol Polymer can be regarded as a copolymer of polyethylene in which varying amounts of the -OH functional group have been incorporated. EVOH is one of the best oxygen barriers available. However, its susceptibility to water requires that for most applications it be laminated into a protective sandwich with materials that will keep the EVOH layer away from water.

Extended Shelf Life (ESL): Involves the pasteurization of a product and the transfer to a package in a controlled atmosphere filler.

Extensible: A material that is capable of being stretched under normal processing conditions.

Extruded Film: The process in which the extrusion of molten resin occurs through a die, which then produces a film.

Extrusion: Technique for producing film. A mixture of resin and plasticizer is fed through a heated barrel where it is made plastic by heat and pressure by a continuously moving screw. The plastic mixture is forced out through a circular die, blown into a bubble, and then wound onto a roll at the end of the bubble.

Extrusion Bonding (laminating): A process wherein a film of molten polymeric material is extruded and immediately pressed between two substrate materials while still hot. The cooled polymer will bond the two materials together.

Extrusion Coating: A process wherein a film of molten polymeric material is extruded onto the surface of a substrate material and cooled to form a continuous coating.

Eye-mark: A machine-recognizable mark, printed on web-fed packaging materials. The eye-mark is the reference point from which the machine will register other operations such as further decoration, heat sealing, or pack cutoff.


FCL: Full container load

Filling Machine: A packaging machine that measures a product from bulk by some predefined value, e.g. volume, mass,
or level in a container

Film Yield: A yield measures the coverage of a film per unit weight. It can be expressed in square inches per pound or meters squared per kilogram (in US or metric units respectively)

Fin Seal: A method of sealing plastic films where the two pieces to be sealed is “substrate-to-substrate” instead of overlapped as “surface-to-substrate”, then heated to form a seal and resulting a finlike protuberance.

Fitment: An injection molded “Spout or Valve” that is typically heat-sealed to a flexible packaging material.

Flexible Packaging: A pack or container made of flexible or easily yielding materials that, when filled and closed, can be readily changed in shape.

Flexo: Flexography Printing – Method of printing on a web press using rubber or plastic plates with raised images. Also called aniline printing because flexographic inks originally used aniline dyes. Abbreviated flexo.

Flexography: A method of printing using flexible rubber or photopolymer printing plates in which the image to be printed stands out in relief. Fluid ink metered by an engraved roll is applied to the raised portions of the printing plate and then transferred to the substrate.

Fogging: A buildup of water droplets on the surface of a film.

Foil (AL): A thin gauge (6-12 microns) aluminum foil laminated to plastic films to provide maximum oxygen, aroma and water vapour barrier properties. Although it is by far the best barrier material, it is increasingly being replaced by metallised films,
(see MET-PET, MET-OPP and VMPET) because of cost.

Food Service: Practice or business of making, transporting and serving or dispensing prepared foods, as in a restaurant or commissary

Form-Fill-Seal Machines: A filling machine that is fed with a flexible packaging stock from a roll. The stock is folded to the desired pack shape and stabilised by heat sealing. The product is placed into the formed pack, and the remaining opening is sealed. Machines can be configured so that the product travels horizontally through the machine (horizontal form-fill-seal) or vertically through the machine (vertical form-fill-seal).


Gauge: A unit of measurement equal to a hundredth of a mil. Thickness of a plastic film(1/1000”=.001”=100 gauge)

Gravure Printing: (Rotogravure). With gravure printing an image is etched on the surface of a metal plate, the etched area is filled with ink, then the plate is rotated on a cylinder that transfers the image to the film or other material. Gravure is abbreviated from Rotogravure.

Gusset: The fold in the side or bottom of the pouch, allowing it to expand when contents are inserted


Haze: The proportion of light which scatters in passing through a plastic film. Measured in percentage (the lower the percentage, the clearer the film), haze distorts colors and imparts a dusty, cloudy appearance to the film.


K – Seal: A stand-up pouch that is made from one web of film. The front, gusset, and back are continuous, so there is no seal at the gusset. Hold more weight than Doy-style pouches, so are commonly used for products weighing more than one pound.

Kinetic Coefficient of Friction (COF): The ratio of frictional force to the gravitational force acting perpendicular to the two film surface (The results are expressed as a ratio; Lower COF = more slippery film)


Lamination: A laminating process in which individual layers of multi-layer packaging materials are laminated to each other with an adhesive.

Lap Seal: A method of sealing plastic films where the two pieces to be sealed are overlapped as “surface-to-substrate”, then heated to form a seal.

LCL: Less container load


Machine Direction (MD): The direction parallel to a material’s flow through a machine. Flow direction through a machine may impart directional properties to a material.

Maximum Fill Temperature: The maximum product temperature that this fitment is rated for.

Metallizing: The deposition, in a vacuum chamber, of vaporised aluminum molecules over the surface of a plastic film or paper substrate, thus providing a lustrous metallic appearance.

Micron: A depreciated, although still used, term for micrometer. One millimetre = 1,000 micrometres.

Mil: A thousandth of an inch. Example: A 0.60 mil film is 0.0006 inches in thickness.

Moisture Transmission: The amount of moisture that is capable of permeating through a given area of film per day. Units are in grams of moisture per 100 in2 of film per 24 hour period.


Offset Printing: An indirect printing process in which the inked image created by the image-producing plate is transferred to an intermediate roll (the blanket roll) and subsequently applied to the substrate.

Opacity: The ability of a material to stop the transmittance of light.

OPP: Oriented PP (polypropylene) film. A stiff, high clarity film, but not heat sealable. Usually combined with other films,(such as LDPE) for heat sealability. Can be coated with PVDC (polyvinylidene chloride),or metallized for much improved barrier properties. They are used for high-clarity wrapping stock and when printed they are the predominant film for snack food packaging. OPP has excellent clarity, low elongation, and good moisture barrier properties. Gas barrier and heat sealability are provided by other added material layers.

Oxygen Transmission (O2): The amount of pure oxygen that is able to permeate through a given area of film per day.


Packaging Line: A group of integrated special-purpose machines that combine product and packaging inputs and produce a new product. The individual machines, each performing a different function, are referred to as stations.

Pantone Matching System (PMS): A commercial color specifying system commonly used in graphic arts. Pantone Inc. produces books containing color swatches printed on selected substrates. Each color is identified by a number code. Designers can reference the numbers when calling up different ink colors during discussions with customers, printers, and ink producers.

Pasteurization: A process to extend food product shelf live by using heat.

Permeability: The property of a film or package that permits the diffusion of gases and liquids through an essentially continuous film or container.

PET: Polyester, (Polyethylene Terephtalate). Tough, temperature resistant polymer. Biaxially oriented PET film is used in laminates for packaging, where it provides strength, stiffness and temperature resistance. It is usually combined with other films for heat sealability and improved barrier properties.

Pinholing: Minute holes in thin-gauge aluminum foils caused by impurities. Pin holing seriously reduces a foil’s barrier properties

Ply: A single layer, as would be found, for example, in a multilayer laminate.

Polyester (PET): A polymer made by the reaction of a dibasic acid and a glycol. PET has the highest tensile strength, stiffness, and use temperature of the commodity packaging polymers. It also has good clarity and is a good all-round barrier. PET films are used where high strength or high use temperatures are required. A major PET application is for carbonated beverage bottles.

Puncture Resistance: Performed on an Elmendorf puncture/tear testing machine, and uses a 4” diameter sample of film to measure its resistance to puncture or impact (Results are in force grams/diameter (4”).

PVC: Polyvinyl chloride. A tough, stiff, very clear film. The oriented version is used mainly for shrink film applications.

PVDCPolyvinylidene Chloride: A very good oxygen and water vapor barrier, but not extrudable, therefore it mostly used as a coating to improve barrier properties of other plastic films, (such as OPP and PET) for packaging.


Register: Exact alignment of one part or operation with another part or operation. Most often applied to printing to describe whether applied colors are in their exact correct position relative to one another.

Release Coating: A coating applied to the non-sealing side of cold sealable packaging films and laminates supplied in a roll form that will allow the packer to unwind these films or laminates on packaging machine.

Resin: A solid or semi-solid organic material which has an indefinite and often high molecular weight; it exhibits a tendency to flow when subjected to stress and usually has a distinct softening or melting temperature range.

Retort: The thermal processing or cooking packaged food or other products in a pressurized vessel for purposes of sterilizing the contents to maintain freshness for extended storage times. Retort pouches are manufactured with materials suitable for the higher temperatures of the retort process, generally around 121o C.

Retortable Pouch: A flexible pack able to withstand the rigorous temperature and pressure conditions of a commercial retort. Retortable pouches, or retort pouches, are constructed of a laminate composed of polyester, foil, and a polyolefin heat-seal
medium. The military is the main consumer of retorted foods.

Reverse Printing: The majority of all packaging are reverse printed. In this case, the outermost layer is printed on the backside and laminated to the rest of the multi-layer structure. While not mandatory in all industries, it is the preferred method for the food industry as it guarantees there will be no ink contact with the food product and takes advantage of the glossy exterior surface of the printed film.


Secondary Pack: A pack or containment of a primary pack.

Shelf Life: The expected time within which the quality of a product is acceptable.

Shelf Stable: A food product that has an extended shelf life with no need for refrigeration or other special storage conditions.

Spot Color: A specified color (for example, one chosen from a PMS color book) used instead of combining the four process colors.

Spouted Pouch: A recloseable or resealable pouch produced with a weld spout and a cap which allows for recloseablility in a flexible package, particularly appropriate for liquids. Many forms and sizes of caps and spouts are available.

Surface Print: The process whereby the ink is deposited directly onto the outermost surface of the packaging film or material. The process is most commonly used in short run printing. A UV (ultraviolet) coating may be added to provide a hard exterior finish that prevents the ink from flaking or chipping.


Tear Propagation: The ability of a packaging material to continue to easily tear once the tear has been initiated. Some plastics, such as polyethylene, have no tendency to continue to propagate an initiated tear.

Tear Strength: The resistance of a material to tearing.

Tensile Strength: The amount of strength required to break a 1” wide strip of film (Results are in gram force/sq inch).

Three Side Seal Pouch: A pouch made from two pieces of film, sealed on three sides leaving one side open. This has no gusset.

Tolerance: Permissible maximum and minimum deviation from the specified dimensions or qualities.


Vacuum Filling: The filling of containers with low-viscosity liquid product by drawing a vacuum on the sealed container. Vacuum filling requires the ability to form a good seal across the container finish and a container with sufficient rigidity that it will not collapse or distort under vacuum.

Vacuum Packaging: A method of packaging where the air is withdrawn from the primary pack. The usual objective of vacuum packaging is to remove atmospheric oxygen, which is implicated in most product degradation. Vacuum packaging when using flexible packaging materials also reduces volume to save transportation cost.

Vertical Form-fill-Seal: A form-fill-seal machine in which the roll-fed flexible packaging material is unwound and shaped while traveling vertically up and down through the machine’s operating stations. A VFFS machine occupies less floor space than a horizontal form-fill-seal machine, but it has the disadvantage of having a single point through which filling or other open-package functions can be performed.

Vibratory Feed Filler: A method of moving product through a filling or transport system by inducing a vibration in a sloped tray at about the resonance frequency of the product. In effect, the product periodically becomes momentarily weightless, and in this state will descend the feed tray slope for a short distance.

Viscosity: The resistance to flow; the thickness of a product. High viscosity (high resistance to flow) means the product is thick and low viscosity (low resistance to flow) means the product is thin.


Web: Paper, film, foil, or other flexible material as it is unwound from a roll and passed through a machine.


Yield: The amount of product that can be produced from a given weigtht of material. Most packaging raw materials are sold by weight. However, because of density differences, the same weight of similar materials can produce different amounts of finished product. For example, the yield for a plastic resin used for film manufacture might be expressed as the number of square meters of film that could be make from 1 kilogram of the material. In other instances, the yield might be expressed in terms of volume per unit weight, or the actual number of physical objects per unit weight.