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Packaging Terminology


A piece of corrugation with a height of 3/16 inch excluding the facing, generally spaced about 33 to 39 flutes per foot.


Applied color lettering. Colored lettering or design of a ceramic nature fused onto bottles. Employs screen printing to transfer glass frit (powdered glass colorant) to the surface of a bottle or glass container. The design is fired, heated in a lehr, and becomes permanently fused.


Co-polymer acrylonitrile-butadiene styrene. Tough, hard, rigid, opaque plastic easily fabricated by injection molding, extrusion and thermoforming. More costly than unmodified and impact grades of polystyrene. Limited use in packaging.

Accelerated Test

Laboratory performance test of a container or coating to evaluate its performance in a shorter time interval than that required under actual service conditions. Example: Performing chemical-resistance tests at elevated temperatures.


Thermoplastic materials, such as Lucite and Plexiglas, made by polymerization of monomeric esters of acrylic acids.


Abbreviation AN. Rigid, natural crystal color, transparent, generally excellent barrier properties, fair resistance to water permeation, good impact strength. Used in thermoforming.


A material such as a hardener, softener, preservative, slip agent, etc., added to a base material in order to achieve a specific result.

Adhesive Bleed

Exudation, or ooze, especially from pressure-sensitive label material. It is the result of cold flow, excessive roll winding tension, excessive heat or improper converting procedures.


Describes any container which consists of (1) a gas-tight, pressure resistant container, (2) a valve (3) a desired product, and (4) a self-contained propellant which forces the product from the container when the valve is opened. Products dispensed from aerosol packages include true aerosols, "wet" sprays (coarse particles), foams, pastes, syrups and powders.

Aerosol Propellants

Liquefied or compressed gases that are packed with a product in a pressure-propulsion container in order to provide sufficient pressure to propel the product through a valve to give the form of discharge desired.

Amber Glass

A brown-colored glass used principally for beer, medicine and liquor containers. The color decreases the effect of some forms of light which would be injurious to the contents of the container.


Also ampoule, ampule, ampoul. A relatively small container made from a glass or plastic tube, the end of which is drawn into a stem and closed by fusion after filling. The bottom may be flat, convex or drawn out as required. Opening is achieved by breaking the stem.


Acrylonitrile. A monomer with the following properties: rigid, natural crystal color, transparent, generally excellent barrier properties, fair resistance to water permeation, good impact strength. Material used in thermoforming.


A controlled temperature process in which glass is gradually cooled in ovens or lehrs to avoid the creation of stresses and strains within the glass due to natural or uneven cooling. The annealing temperature in glass is about 1000 degrees F.

Anti-Skid Corrugated

Corrugated board with embossed or chemically-treated surface, to increase coefficient of friction, so containers made from the treated board will produce a more stable pallet or unit load.


A chemical substance that can be added to plastic resin to minimize or prevent the effects of oxygen attack on the plastic (e.g., yellowing or degradation). Such chemical attack by oxygen may render a plastic brittle or cause it to lose desired mechanical properties.

Antistatic Agent

A substance applied to the surface of a plastic article, or incorporated in the plastic from which the article is to be made, so as to render the surface of the plastic less susceptible to accumulation of electrostatic charges which attract and hold fine dirt or dust on the surface. There are two types: (1) metallic devices, and (2) chemical additives, either internal or surface applied.

Applicator Cap

A container closure designed so that it may be used to apply the contents of the container, such as oil and grease spouts or daubers.

Applicator Rod

Short glass rod 2 mm to 4 mm in diameter used in conjunction with an applicator cap. The end which enters the cap is cut square. The other end may have a variety of glazed finishes.


Acceptable quality level. The maximum percentage or proportion of variant (or defective) units in a lot or batch that, for the purposes of acceptance sampling, can be considered satisfactory as a process average.

Aseptic Packaging

A technique for creating a shelf-stable container by placing a commercially sterile product into a commercially sterile container. The process involves sterilizing a product and its intended container (usually separately) and then bringing them together within a sterile environment for filling and sealing. The sealed container is designed to maintain a sterile product until the seal is broken.


Products produced from resins that can withstand 250 degrees for 45 minutes.


A pressure vessel into which steam or other vapor can be introduced at a suitably high temperature to sterilize packages or other objects placed therein. Similar pressure vessels used for sterilizing food products packed in glass jars or cans are normally called retorts.

Average Wall Thickness

A number obtained by adding the thickest wall section measurement of a container to the thinnest wall section and dividing by two. It does not describe the distribution of plastic material in a container.

Avoirdupois Weight

System of weights used in Great Britain and U.S. for the measure of goods other than gems, precious metals and drugs. Designated by "oz" or "oz av" and "lb" or "lb av". Sometimes, when a container is meant to hold a specific product such as honey or talcum powder, the bottle capacity is stated in auvoirdupois ounces rather than in fluid ounces. For example, a typical 1 lb. honey bottle holds 11 to 12 fluid ounces.


A piece of corrugation with a height of 3/32 inch excluding the facing, generally spaced about 47 to 53 flutes per foot.

Back Off

Loosening of cap; can be caused by improper cap application torque, improper mating of the cap to the container, or improper liner facing and/or backing.

Backing Liner

The compressible paper material, usually pulp or newsboard, to which the liner is attached or adhered. This compressible paper material compensates for any irregularities on the sealing surface. Also provides additional strength, or water resistance, or better appearance.


A sealed, usually spouted plastic bag inside a rigid outer container, generally used for packaging liquid products of varying viscosities. The outer box may be disposable or reusable. The container itself may be be either partially emptied and resealed or may never be opened to ambient air (i.e., wine boxes). Consumer sizes usually range from one to six gallons while process and transportation sizes range from 55 to 300 gallons.


Wire handle for carrying purposes, with or without grip, fastened to ears that are riveted or welded to opposite sides of a container.

Bar Code

An identification symbol where the value is encoded in a sequence of high contrast, rectangular bars and spaces. The relative widths of these bars and spaces contain the information. Identification is by visual or electronic means.


Barex is a polymer composed primarily of acrylonitrile, with methylacrylate and butadiene as comonomers. It offers excellent gas barrier properties, good impact and chemical resistance. Barex containers are used for many agricultural chemicals. Barex is a registered trademark of BP Chemical Inc.

Barrier Material

Term used to prescribe one of two classes of specialized packaging materials that provide environmental protection to the package contents: (1) gas-, moisture-, or light-proof materials that control or eliminate the amount of these environmental constituents that pass into or out of a package; (2) a porous material possessing a structure that prevents the passage of microorganisms that might contaminate the contents of a package.


A narrow, round projection above or below the surface.


The sloping edge of a container or part. A bevel adds a short flat span at the junction of two sides of a container.


The relative number of actual or suspected microorganisms of whatever type found on a specific article at a specific time. May also apply to the level of microorganisms found in a specific area during a procedure such as air sampling.


A particular style of straight sided oblong bottle used primarily by pharmaceutical concerns. Also called space saver and wide mouth packer.

Bleached Pulp

Any type of pulp whitened by an oxidizing treatment, usually with a hypochlorite or hydrogen peroxide solution, or by a reducing treatment such as with sulphur dioxide or sulphites.

Blister Packaging

A product is secured between a preformed (usually transparent plastic) dome or "bubble" and a paperboard surface or "carrier". Attachment may be by stapling, heat-sealing, gluing, etc.

Blow Molding

A method of fabrication in which a warm plastic parison (hollow tube) is placed between the two halves of a mold (cavity) and forced to assume the shape of that mold cavity by the use of air pressure.

Blow Pin

Part of the tooling used to form hollow objects or containers by the blow molding process. It is a tubular tool through which air pressure is introduced into the parison to create the air pressure necessary to form the parison into the shape of the mold. On some blow molding systems, it is a part of, or an extension of, the core pin.

Blown Glass

Containers manufactured from molten glass that are formed by air pressure, in molds, similar in fashion to plastic molding. The finished containers are ejected or extracted from the mold, then annealed (heated and cooled) to temper the glass.


A surface whitening or discoloration of a plastic bottle. It is the result of physically induced (i.e., by impact) or chemically induced phase separation of the (1) ingredients in the plastic mold compound or (2) the molecular orientation of the plastic.


A heavy weight thick sheet of paper or other fiber substance (from 0.012 to 0.030 inches and up). Variations: cardboard (non-specific term), chipboard, fiberboard, paperboard, containerboard, boxboard, tagboard.

Boston Round

A style of bottle characterized by a round cylindrical shape with a short curved shoulder. Typically used by the drug and chemical industries.

Bottom Plate

The part of the mold which contains the heel (base) radius and the "push up" of the container to be formed.

Bubble Pack

A type of cushioning material that is made by trapping air between two layers of plastic material and using the "bubbles" to protect products inside their shipping containers. See blister packaging.


A plug used to close a barrel or drum bung hole. Called a plug when referring to a steel drum closure.

Burn Line

A dark streak of material in a plastic bottle resulting from decomposed material dislodged from the extruder and incorporated in the bottle.

Buttress Thread

A design of thread profile (cross section) which takes the form of a right triangle or slight modification of that form. It is usually positioned so that the right angle is at the bottom of the thread cross section and adjacent to the neck of the bottle finish. The horizontal leg of the right triangle is the bearing surface for a matching cap thread. The thread sides terminate abruptly in threading, gradually tapering down to the neck finish. The buttress thread is designed to withstand maximum force in one direction only.


A piece of corrugation with a height of 9/64 inch excluding the facing, generally spaced about 39 to 45 flutes per foot.

Cap Seat

The ledge inside the mouth of a bottle, such as a milk bottle, to receive a plug closure.


The volume of space inside a container provided for a given amount of product. Note the difference between capacity and overflow capacity.


A bottle or similar container made of glass, plastic, metal or clay, having a capacity of 3 to 13 gallons. Where the carboy is used for shipping purposes, it is usually designed to be encased in a rigid protective outer container for shipment, often with the use of cushioning materials prescribd by DOT specifications, particularly when the carboy contains dangerous liquids. Carboys are also used for local shipment of spring water, distilled water and drinking water where no protective container is used or only a simple outer container from which the carboy is removed for dispensing purposes.

Case Sealer

A machine for closing the flaps of a case and sealing them with adhesive, tape, or staples. Case sealers differ in capability of accepting one size or random sizes, and sealing only top flaps, or top and bottom, with or without load.


A light-gauge (24-gauge or lighter) metal drum for packaging heavy viscous, semi-solid, or solid materials, such as asphalt, tar, wax, etc.


A chemical substance that speeds up or retards a chemical reaction and does not itself take part in the reaction. A catalyst, when added to coating material, will promote cure of coating at lower than normal bake time or temperature, or both.


In plastic blow molding, the parts of the mold that combine to provide the container body shape.


Cubic centimeter. A unit for measuring volume, where 1 cc = 0.0338 ounce.

Cellophane Tape Test

A quick but not precise method for examining the adherence of printing on plastic films. A piece of cellophane adhesive tape, or other pressure-sensitive tape, is adhered to a section of printing and then pulled off in one motion to see whether or not the ink will come off with it. The speed of the pulling is important.

Cellulose Band

A band made of hydrated cellulose film that is extruded in continuous tubing form. The cellulose tubing is then processed and printed in this form and cut into individual bands of predetermined lengths. When the Celon is applied to the finish of the container, it is allowed to air dry. During this air-drying period, it shrinks to form a skin-type film over the neck finish of the container.

Ceramic Labeling

A process of labeling glass containers with a label composed of colored glass that is fused to the container.

Cert. of Compliance

Certificate of Compliance. A document signed by an authorized party affirming that the supplier of a product or service has met the requirements of the relevant specifications, contract or regulation.

Chemical Resistance

Ability of a material to retain utility and appearance following contact with chemical agents. Chemical resistance properties include stain resistance, swelling resistance, moisture resistance, corrosion resistance, etc.

Child Resistant Cap

Also CRC. A closure that requires dissimilar motions which make removal by a child difficult and is compliant with the Code of Federal Regulations Title 16, Part 1700.


A low quality non-test paperboard made of waste paper for use where specified strength or quality is not necessary. May be bending or non-bending, used for corrugated pads or as dividers, or as filler in thicker paperboards. Also used in the manufacture of spiralwound cans.

Choked Neck

A narrowed or constricted opening in the neck of a container.


A clamping device designed to tighten screw caps.


Extruding two or more layers of thermoplastic materials to form a combined film sheet or molded unit. Limited to plastics.


Contraction of the walls of a container (e.g., upon cooling) leading to permanent deformation of the container.

Collapsible Core Mold

Mold action in the manufacture of closures. This technology utilizes a three part core. After the cavity is removed following the injection cycle, the center portion of the core (core wedge) retracts while the two outer core halves move radically inward. Once the closure thread is cleared, the stripper sleeve moves forward to eject the closure.

Collapsible Tube

Cylindrical container of thin, flexible metal with integral shoulder and neck, with a screw cap closure made of plastic. Collapsible tubes can also be made of paper, films, plastics, etc. They may have wax, resin or lacquer linings. Collapsible tubes are usually filled through the bottom and subsequently closed by multiple folding of the bottom, or crimped with a metal clip or sometimes welded tight.

Color Concentrate

A measured amount of dye or pigment incorporated into a predetermined amount of plastic which is then "let down" (mixed) into larger quantities of virgin plastic material to be used for molding. The "concentrate" is added to the bulk of plastic in a measured quantity in order to produce a precise, predetermined color of the finished articles to be molded.

Column Crush

A test performed on a small sample of corrugated which is a measure of the compression strength of that sample. Also referred to as edge crush and short column crush.


Ability of a container, whether lined or unlined, to resist degradation of or by the product contained.

Composite Can

A rigid container with the body made of fiberboard or fiberboard in combination with other materials such as metal foils or plastics. One or both ends may be made of metal, plastic or other materials.


The resin, along with modifiers, pigments, antioxidants, lubricants, etc., which are to be molded or blown into final form.

Compression Molding

A method of forming objects from plastics by placing the material in a confining mold cavity, then applying pressure, and usually heat.

Continuous Thread

An uninterrupted protruding helix on the neck of a container to hold a screw-type closure. Continuous thread finishes have GPI finish designations in the 400 series. See Also CT.

Convolute Can

A can with the body made of fiberboard formed by convolute winding of paper to build up the required thickness.


A material whose chemical structure is made up of long chains of two differently structured chemical units (monomers), which repeat a more or less regular pattern in the chain. Also see Polymer.


Defect in glass containers. A narrow, stringy band of glass of a composition different from the rest of the glass surrounding it.


A closure made of cork, or, by extension, any plug-type closure.

Cork Finish

A finish which is closed by means of a cork.

Corrugated Board

A packaging material consisting of a central member (medium) which has been fluted on a corrugator and to which one or two flat sheets of paperboard have been glued to form single-faced corrugated board or double-faced (single wall) corrugated fiberboard. The combination of two mediums and three facings is called double wall and the combination of three mediums and four facings is called triple wall. Corrugated board is generally made in four flute sizes, designated A, B, C and E.

Cover Backing

Material that is used to enclose an item within a blister pack. It is the material, such as hard or soft temper foil, foil/paper laminates, coated board, etc., that seals to the blister material.

Crab Claw Seal

Named for its shape, it is a thin flexible protrusion molded into a closure which will compress against a bottle sealing surface during normal capping operations. It prevents leakage and will seal a variety of bottles. The bottle land (the bottle's sealing surface) must be flat and free of defects because this sealing method requires compression to be effective.


Small, thin or bare spots in an applied coating that have the appearance of pockmarks.


Fine cracks which may extend in a network on or under the surface or through a layer of glass or plastic material.


Child resistant closure. There are several types that have been developed for products that constitute a hazard to small children. Basic principles of CRC's are (1) press-turn, (2) squeeze-turn and (3) combination lock and hidden key.

Crimp Seal

(1) Applying a seal of aluminum or coated aluminum foil by crimping with a die, generally corrugated. (2) A method of heat-sealing thermoplastic coated papers or thermoplastic films with the pressure exerted by knurled wheels or bars having a corrugated surface. (3) A small flat metal piece that is crimped mechanically to parts of flat strap to maintain tension and connect them permanently.

Crown Cap

This is a crimped closure. Flutes are pressed into the flaring skirt of a shallow metal disk, which holds an inner disk of resilient lining material that forms the actual seal.

Crown Finish

The neck finish on beer and beverage bottles sealed with a crown cap.

CT Finish

Continuous thread finish. An uninterrupted protruding helix on the neck of a container to accommodate a screw type closure. Designed primarily to seal container finishes with the GPI finish number designations in the 400 series.


Glass, from containers not approved by selectors, that has been crushed or broken and is added to the batch to be remelted and formed into new containers; or recycled broken glass that is used in the manufacture of new glass.


A complete repeating sequence of the operation in a specific process in molding. Cycle time is measured by the elapsed time between one point in the cycle to the same point in the next cycle.


Department of Transportation. United States governmental body that regulates the shipment of materials on public right of ways.

D.O.T. 12A

Overpack carton for glass or D.O.T. 2E plastics.

D.O.T. 12P

Overpack carton for D.O.T. plastics.

D.O.T. 17C

Steel drum from 5 gallon to 55 gallon in size, O/H, single trip.

D.O.T. 17E

Steel drum from 5 gallon to 55 gallon in size, T/H, single trip.

D.O.T. 17H

Steel drum from 5 gallon to 55 gallon in size, O/H, single trip.

D.O.T. 21P

Overpack carton for D.O.T. plastics.

D.O.T. 2E

P/E molded container not exceeding 5 quarts, T/H. Requires overpack.

D.O.T. 2S

P/E molded container 5 gallon to 55 gallon in size, T/H, requires overpack.

D.O.T. 2SL

P/E molded container 13.5 gallon to 55 gallon in size, T/H, requires overpack.

D.O.T. 2TL

P/E molded container 5 gallon to 14 gallon in size, T/H, requires overpack.

D.O.T. 2U

P/E molded container 1 gallon to 55 gallon in size, T/H, requires overpack.

D.O.T. 34

P/E molded container 2-1/2 gallon to 30 gallon in size, T/H, reusable.

D.O.T. 35

P/E molded container NE 7 gallon in size, O/H, non-reusable.

D.O.T. 37A

Steel drum 2 gallon to 55 gallon in size, O/H, single trip.

D.O.T. 37B

Steel drum 5 gallon to 55 gallon in size, T/H, single trip.

D.O.T. 37C

Steel drum 5 gallon in size, O/H, non-reusable.

D.O.T. 37D

Steel drum 5 gallon in size, T/H, non-reusable.

D.O.T. 37P

Steel drum w/poly liner 5 gallon to 15 gallon in size, non-reusable.


Normally part of an applicator closure. Popular for cosmetic, household and pharmaceutical products. Usually fitted with sponges or cotton, wool or felt pads, like those provided with liquid shoe polish or bingo ink bottles.


Depressing (in a blanking die) a portion or portions of the cap below the ordinary surface level, usually to form lettering or decoration. Sometimes the background, rather than the lettering itself, is debossed, leaving the letters at the original level of the cap, thus giving the appearance of embossing; otherwise the lettering itself is pressed down, giving the appearance of engraving.

Deep Skirt

A cap having a deeper skirt (more "H") and generally a heavier thread than the 400 finish series.


Any technique or method which removes excess material (flash) from a molded article, specifically from those places where parting lines of the mold may have caused the excess material to form.


Weight of a gas, liquid or solid substance per unit of volume, expressed in grams per cc or pounds per cubic foot.

Depressed Thread

Thread on the finish of glass containers in which the thread is reduced in depth or "depressed" at the two points where the thread crosses the mold parting line.


A drying agent possessing a high affinity for water vapor, it is used to control the humidity level in sealed packages.


Treatment of plastic materials which minimizes the effects of static electricity on the surface of the articles. Can be accomplished either by spraying the surface with specific materials, or incorporating materials into the molding compound. Destaticization prevents dust and dirt from being attracted to and/or clinging to the surface of the article.


Any tool or arrangement of tools designed to cut, shape, or otherwise form materials to a desired configuration.

Dimension "C"

The "C" dimension of a bottle is the opening control diameter (inside diameter) at the top of the neck finish.

Dimension "E"

The outside diameter of the neck. The difference between the "E" and "T" dimensions divided by two determines the thread depth.

Dimension "H"

BOTTLE "H" Dimension: The height of the neck finish. Measured from the top of the neck to the point where the diameter "T", extended down, intersects the shoulder. The bottle finish "H" must be greater than closure "H" (corrected for the thickness of the compressed liner or other sealing elements).

CLOSURE "H": The "H" dimension is measured from the inside top of the closure vertically down to the bottom of the closure skirt. Effective "H" must take into consideration the liner, or other sealing element, if one is used. To determine effective "H", liner thickness or other sealing element under compression must be determined and subtracted from unlined "H".

Dimension "I"

The minimum opening through the finish and neck expressed by measuring the inner diameter of the neck at its narrowest point. Specifications require a minimum "I" to allow sufficient clearance for filling tubes. Linerless closures, with a plug or land seal, and dispensing plugs and fitments require a controlled "I" dimension for proper fit.

Dimension "L"

"L" dimension is the minimum vertical dimension to the top of a concealed bead for closure thread clearance. It is measured from the top of the finish to the point where diameter "E" extended parallel to centerline intersects the bead.

Dimension "S"

Measured from the top of the finish to the top edge of the first thread. The "S" dimension is the key factor which determines the orientation of the closure to the bottle and the amount of thread engagement between the bottle and cap.

Dimension "T"

The outside diameter of the closure, including the thread. The tolerance range of the "T" dimension determines the mate between the bottle and the closure.

Disc Top

Injected molded two piece dispensing closure. The one hand, one finger action closure has gained high consumer preference particularly on personal care and sun care products. Contrasting colors can be incorporated into the design by selecting different colors for the closure body and disc. Also called Press Top.


A device, made of various materials, which separates the space within a container into two or more spaces, cells, compartments, or layers. Dividers may be plain, interlocking, scored, horizontal, vertical, or diagonal. The primary purpose of dividers is to separate the articles and/or to furnish cushioning.


A closure where the whole top surface is domed, starting at the shoulder. Doming adds to streamlining of package appearance and to the apparent height.

Drawn Container

A container made by the metal drawing process which consists of forcing a flat piece of metal into or over a die. This results in a container body with an integrated bottom end.

Drop Test

Any test method in which the article being tested is dropped in a specified manner for a specified number of times or until the article fails from impact. Normally done in full cases from heights as specified by DOT specifications (10 points), but may be designed to incorporate effects of de-acceleration, pallet loading, temperature, humidity, or other variables that could lead to product damage.

Dry Blend

Refers to a molding compound containing all necessary ingredients mixed in a way that produces a dry, free flowing, particulate material. This term is commonly used in connection with polyvinyl chloride molding compound.


A piece of corrugation with a height of 3/64 inch excluding the facing, generally spaced about 90 to 98 flutes per foot.


(1) Ears are attached to metal pails to hold the bail or handle. (2) The name given to the finger grip of pressed glass between the shoulder and finish of a 1/2 gallon, gallon, or other glass jug to facilitate holding it.

Easy-Open End

A can end that is scored on the circumference and fitted with a gripping device (tab) for easy removal of end.


Extrusion blow molding. A parison is extruded into a mold cavity and then blown into a bottle.


A substance having rubber-like or stretching qualities.


Raised design or lettering on the surface of an object accomplished by pressure of dies, rollers, printing press, etc.


The Environmental Protection Agency (EPA). One function of the EPA is to regulate the labeling, packaging and registration of pesticides under the Federal Insecticide, Fungicide, and Rodenticide Act. The EPA is the sole federal agency with the authority to regulate child-resistant packaging for pesticides. Since March 9, 1979, child-resistant packaging has been required for all residential use pesticides labeled with a human hazard signal word of danger or warning.


Expandable polystyrene. A generic term for polystyrene and styrene copolymers, supplied as a compound with physical blowing agents and other additives which can be processed into low density foamed articles. A major end-use is cushioned packaging. Low molding pressures and economical tooling make EPS molding an inexpensive method of producing foam shapes.


Environmental stress crack resistance. A measure of the susceptibility of a plastic bottle to crack or craze under the influence of certain chemicals, stresses, or other agents.


(1) To treat a material with an acid, leaving the parts of the material which remain in relief to form the desired design. (2) To corrode the interior of a tin can sufficiently to be visible as an irregular instead of polished surface.


Ethylene-vinyl acetate. Copolymers from these two monomers retain many of the properties of polyethylene, but have considerably increased flexibility for their density. Elongation and impact resistance are also increased. Used for making film, coatings, and adhesives. The combination of high clarity, puncture resistance, impact strength, and low heat-seal temperature make EVA desirable for flexible packaging.


Ethylene-vinyl alcohol copolymers. Plastics produced by combining the process ability of ethylene polymers with the barrier properties obtained from vinyl and alcohol polymers. The result is a material offering excellent process ability and superior barrier to gases, odors, fragrances, solvents, etc.


A substance, generally having some adhesive action, added to a product, such as an adhesive, ink, or paint, to reduce the amount of the primary resin required per unit area.

Extruded Film

Film produced by extrusion of molten resin through a die.


A method of shaping a plastic material by forcing it, with the application of heat and pressure, through an orifice in a continuous fashion.

Extrusion Blow Molding

A method of fabrication in which a hollow plastic tube (parison) is forced into the shape of the mold cavity by internal air pressure. Post finishing of the product is required.

F-Style Can

Called "F" because it was originally created to package Flit insecticide. It is a rectangular metal can with a pouring spout.


Food & Drug Administration. This agency governs what items may be used in foods, drugs and cosmetics. It regulates the labeling of foods, drugs, cosmetics and devices under both FPLA (Fair Packaging and Labeling Act, 1966) and FFDCA (Federal Food, Drug & Cosmetic Act).


Feature is one of the search criteria. In all product types - Glass, Plastic and Closures - a Feature is one outstanding property of the item. Selecting a Feature in addition to a Style can effectively narrow the results of a search. In the Glass and Plastic product types, Features include Indent (for label), Round Shoulder, Footed, etc. In the Closure product type, a Feature can define a Style of closure. For example, Features such as Flip Top, Trigger Sprayer and Turret all identify Dispensing Style closures. In Continuous Thread closures, a Feature identifies a property, such as smooth, ribbed, tall, etc.

Fill Point

The level to which a container must be filled to furnish a designated quantity of the contents.


An inexpensive, inert substance added to a plastic to make it less costly. Fillers may also improve physical properties, particularly hardness, stiffness and impact strength. Filler particles are usually small.


(1) Unsupported, basically organic non-fibrous, thin, flexible material not usually exceeding 0.0003 inch in thickness. (2) Generally, a thin coating.


In general, the plastic forming the opening of a container shaped to accommodate a specific closure. Also, the ultimate surface structure of an article. Finish is one of the search criteria as described below. In the Glass and Plastic product types, Finish is expressed as 24-410, 20mm Crimp, 38mm Snap, etc. The Finish description reflects the outside diameter of a bottle or jar's neck in mm's, and a thread configuration or some other description of how the closure fits on the container. In the Closure product type, Finish refers to the thread configuration. Common configurations are -410, -2030, etc.


A plug that fits within the neck of a bottle to control the flow of products such suntan lotions, coupled with a non-dispensing closure. The primary (non-dispensing) closure is usually removed each time to provide the desired function, while the fitment (plug) remains in place.

Flame Treating

Exposing plastic bottles or film to a a gas flame to promote oxidation and increase the polarity of the surface, which makes them receptive to inks, lacquers and adhesives. The amount of flame treatment is dependent on the condition and position of the flame and the time of exposure.


(1) Generally, a projecting or flared edge, rib, etc., to hold, strengthen or facilitate the use of an object or part. (2) In steel drums and cans, a right angle flare or nearly right angle formed in the ends of the body-cylinder to enable heads and bottoms to be double seamed to the body. (3) In drum closures, the threaded fitting which receives the closure plug.

Flange Cap Seal

Tamper resistant closure over plugs in drums and pails.


Extra plastic attached to a molding along the parting line; it must be removed before the part can be considered finished. Also called a fin or cut-off.

Flash Line

A raised line appearing on the surface of a molding and formed at the junction of mold faces.


A style of narrow-neck bottle, usually of elliptical cross section, with flattened side walls having a width of four or more times the thickness.

Flexible Packaging

Packaging involving the use of such flexible materials as foils, films, paper, flexible sheeting, etc., to form the container, basically wraps, bags, envelopes and pouches.

Flexographic Printing

Formerly called aniline printing. A method of rotary letterpress printing that employs rubber or plastic plates and rapid drying inks. Extensively used in the printing of packaging materials as well as other printing applications.


Clear glass used for all types of containers.


Fluorinated high density polyethylene.


Fluorinated polypropylene.


Single Step Fluorination: Molding of containers using fluorine instead of air. This process creates a chemical reaction by which a barrier layer is created on the interior surfaces of the container. Also called in-line fluorination.

Post Treatment Fluorination: This process of treating existing containers involves exposing the containers to a controlled environment which introduces fluorine to the treatment chamber. The exposure to the fluorine affects a barrier on both the internal and external surfaces of the container in the same manner as Single Step Fluorination.


Liquid or gaseous compounds used as a propellant for aerosols or for refrigerants. Also known as solid thermoplastic materials. Typical fluorocarbons are Teflon (polytetranuoroethylene), TFE (Teflon tetrafluoroethylene), FEP (Teflon fluorinated ethylene propylene and KEL-F (polymonochlorotrifluoroethylene). Fluorocarbons are noted for their chemical inertness and high temperature resistance.


(1) A rib or corrugation on a surface; one of the undulations of a corrugated material. (2) A flat surface in a cylindrical container.

Foil (Laminated)

Foil bonded to other materials such as paper, board, films, etc., by means of an adhesive.

Folding Carton

A container made of bending grades of paperboard. Formed by the maker, and to be set up, filled and closed by the user. Folding cartons are made in a multitude of styles, a few of which are: tuck-end carton, reverse tuck, straight tuck, two-piece and many others. A general class of paperboard container, distinct from set-up boxes and corrugated and solid fiber boxes.

Friction Fit

Refers to a type of plug can closure. The plug is designed so that frictional resistance to movement exists between the plug and the part of the container designed to hold it.


A crystalline finish or pattern on a glass surface.

Gamma Irradiation

Sterilization by means of exposure to a source of gamma rays, normally Cobalt 60.

Gas Transmission Rate

A measure of the permeability of a packaging film to gases by measuring the movement of a gas through the film under specified conditions.


A liner applied between the sealing surface of container lip and closure to provide the ultimate seal.


In a molding process, a restricted section of runner at the edge of an injection mold cavity, serving to permit entrance of the plastic material into the closed cavity and core assembly.


Glass Container Manufacturers Institute. Former name of GPI.

Glass Types

Four types of glass are specified by the U.S. Pharmacopoeia on the basis of chemical durability tests. Types I, II, and III are intended for packaging parenteral preparations and Type NP for non-parenteral products. Type I: Containers normally made of borosilicate glass having a highly resistant composition. Type II: Containers made of commercial soda-lime glass which have been treated on the inside surface at a high temperature to obtain a great improvement in chemical resistance. Type III: Untreated glass containers made of commercial soda-lime glass of average or somewhat above average chemical resistance. Type NP: Untreated glass containers made of ordinary soda-lime glass.


Shine or luster of the surface of a material. If a surface clearly and plainly reflects an image of light, it has a high gloss.


Good manufacturing practices. Regulations promulgated by the FDA under which device manufacturers must produce, package, and label their devices.

Gold Lacquer

A protective coating which has a yellow color. May be of lacquer or baked enamel.

Gold Reverse

The gold-lacquered interior of a closure.


Glass Packaging Institute. A trade association for the glass container and closure industries, with recommended specifications published for glass containers, glass finishes, and metal and plastic closures.


Marks on a container to show fluid levels of contents on a scale of full to empty.


The degree of cloudiness in a plastic material.


High density polyethylene. The resin of choice in blow molding because it is stiff, chemical resistant, has good processing behavior and good environmental stress crack resistance (ESCR). This ESCR makes it a good choice for bleach and detergent bottles where resins having densities between 0.950 and 0.960 and above are commonly chosen. Injection blow molding is a proven and valued processing technique when a container benefits from excellent neck finish and lack of pinch-off.


Space between the level of the contents of a container and the closure. Headspace is required to allow for expansion of a product due to heat or pressure, and to allow the container to be grasped without spilling the contents.


A method of uniting two or more surfaces by fusion, either of the coatings or of the base materials, under controlled conditions of temperature, pressure and time (dwell).

Heat-Seal Label

A label made of paper or other material coated on one side with a heat-seal coating, usually a thermoplastic resin, and characteristically difficult to remove after application.

Heat Stability

The resistance of a plastic material to chemical deterioration during processing.

Heat Transfer

Process similar to hot stamping except preprinted images on a carrier web are applied by heat and pressure to the surface to be printed. Multicolor decoration is a one-step process. Method is widely used for decorating plastic bottles but also for glass and folding cartons.

Heat Transfer Label

Labels printed with special inks on a web from which they are transferred to containers by application of heat as they contact the container surface.

Heavy Metals

A series of metallic elements within the periodic table of elements of relatively high atomic weights that, upon exposure, tend to collect in specific body organs and at high levels have been shown to be toxic. Historically, most ink pigments were derived from compounds containing heavy metals. Heavy metals include lead, arsenic, cadmium, mercury, selenium, barium, chromium and antimony.


The lower portion of a glass or plastic container, starting with the bearing surface of the bottom and including a small portion of the lower side-wall.

Heel Radius

The degree of curvature at the extreme bottom end of a bottle extending upward from the bearing surface. Also called base radius.

Helix Angle

The measure of inclination of the thread, from a plane perpendicular to the vertical centerline of the thread finish.

Hermetic Seal

A seal that will exclude air and will be leak proof at normal temperatures and atmospheric pressures.


Also hi-lo. Double-wall corrugated board combining both A-flutes and B-flutes.


High impact polystyrene. Produced from styrene monomer along with elastomers. The resulting opaque material offers good dimensional stability, low-temperature impact strength and rigidity. HIPS is readily molded to precise tolerances. It can be combined with other plastic parts to make units which are attractive and tough. Disadvantages include poor barrier properties, poor grease resistance, and poor high-temperature resistance.


A polymer, consisting of (neglecting the ends, branch junctions, and other minor irregularities) a single type of repeating unit. Also see "polymer".

Horizontal Bar Code

A bar code or symbol presented in such a manner that its overall length dimension is parallel to the horizon. The bars are presented in an array which looks like a picket fence.

Hot-Melt Adhesive

Adhesive, solid at room temperature, which is liquefied by heat, applied molten, and forms a bond by cooling and solidifying. Based on thermoplastic polymers generally modified with resins and/or waxes. Usually used in range of 250 to 400 degrees F.

Hot Filling

The product, usually a liquid, is passed through a heat exchanger and then filled at elevated temperatures. The closure is then applied. Any microbiological contamination on the inner surfaces of the container (usually a bottle) is destroyed by the hot liquid without heating the bottle itself, as in the technique of in-bottle pasteurization.


Intermediate bulk container. A large bag, box or other container capable of transporting, storing, and discharging one-half ton (1,000 lbs) or more of material.


See injection blow molding.


Inside diameter of a container or container part, ordinarily of the container shell or body.

Impact Resistance

Relative susceptibility of plastics to fracture by shock as indicated by the energy expended by a standard pendulum type impact machine. The ability to withstand mechanical abuse in service, as related to dropping and impacts.

Impact Strength

(1) The ability of a material to withstand shock loading. (2) The amount of energy needed to fracture, under shock loading, a specified test specimen in a specified manner.

Imperial Gallon

The British gallon, equal to 277.274 cubic inches, or about 4.8 U.S. quarts.

In-Mold Labeling

Process by which preprinted labels are placed in the mold before the plastic is injected into the mold. This form of labeling is very economical for large manufacturing runs, as it does not require any additional processes on the production line or post production decorating.

Induction Sealing

A sealing technique in which excitation by means of high frequency electric impulse causes materials to bond. Usually associated with inner seals whether they are applied separately or as an integral part (metal or plastic) of the closure.

Injection Blow Molding

A two-stage process of plastic bottle manufacturing where a preform or parison is injection molded. The bottle finish is formed at this time. The preform is then transferred to a blow mold where the bottle takes its final shape.

Injection Mold

A mold into which a plastic resin is introduced by pressure from an exterior heated cylinder.

Injection Molding

A molding process whereby a heat softened plastic resin is forced from a heating cylinder into a relatively cool cavity which gives the product a desired shape.

Ink Jet Printing

Non-impact method of printing whereby tiny drops of ink are formed into letter, number or other configuration and sprayed on to the object or surface to be printed. Can be used for high speed printing. A major application is for code marking beverage cans.

Inner Seal

An extra seal of comprising a sheet that is resistant to water vapor or vapor from some chemical, and adhered to the top end of a container below the regular cover or closure, to give added protection to the contents, such as: hygroscopic materials like soluble coffee, volatile chemicals such as chloroform, or creams and ointments containing volatile ingredients. The added protection includes: barrier to movement of water vapor or volatile chemicals and perfumes, and protection against tampering, contamination and leakage.

Interrupted Thread

Threads on the neck finish of bottles that are not continuous, having gaps at seam areas to avoid scratching internal coatings on closures.

Irradiation, Atomic

As applied to plastics, refers to bombardment with a variety of subatomic particles, generally alpha-, beta-, or gamma rays. Atomic irradiation has been used to initiate polymerization and copolymerization of plastics and in some cases to bring about changes in the physical properties of a plastic material.


A champagne bottle holding the same amount contained in four ordinary champagne bottles (102-2/5 oz).


Tool or fixture that is used for holding a component that is to be worked on during the manufacturing, decorating and assembly processes.


A bottle, usually of half-gallon or larger capacity, fitted with a handle.


Knocked down. Applied to boxes, cartons, cases, etc., which are stored or shipped flat, that is before the package is set up for loading.


Indented or crimped portion on the skirt at the top of the cap for holding liner in cap, used as a grip for applying cap and also for a better hold or grip for removing. Also provides non-skid surface during threading operation.


A chemical wood pulp made by the sulphate process, or paper or paperboard made from such pulp. It is brown in color and is the strongest pulp product made from wood.

Label Panel

That portion of the body of a container to which labels are affixed or decoration imprinted.

Land Dimension

The sealing surface of a glass or plastic bottle.

Land Seal

Also called flat land seal. The Land Seal requires that a flat surface molded into the closure makes contact against the top of the sealing surface (land) of a container. This seal works best when the closure contains a liner material. It is best suited for threaded closures.


Low density polyethylene. LDPE is similar to HDPE in composition. It is less rigid and generally less chemically resistant than HDPE, but more translucent. Used primarily for squeeze applications. LDPE is significantly more expensive than HDPE, but will yield a glossy bottle when produced in colors.


A continuous-belt oven for the annealing of glass, and for fusing of ceramic color on to glass.

Lever Lock

A method of holding a lid on a full open head drum by means of a lever-operated tightening device or ring that can be locked in closed position.

Light Resistance

The ability of a plastic item to resist fading when exposed to sunlight or ultraviolet light. Nearly all plastics tend to darken when exposed.


In the manufacture of closures, a disc of paper, cork, composition, etc., retained in a closure to provide a sealing surface against the finish of a container.

Liner Fall Out

Liner falling out of cap; usually due to shrinkage, loss of moisture or under sized punching.

Linerless Closure

A one-component thermoplastic closure incorporating a sealing "fin" which, when applied to a container with the appropriate finish, seals most liquids including those that are volatile.


The extreme outer edge of the top of a container intended to facilitate pouring.


Decorating of flat surfaces by means of plates. Lithography is the prime method for decorating cans, but must be done on the sheet steel before the can is formed.


Linear low density polyethylene.

Locking Ring

Metal closing ring around the rim of a full-removable-head container intended to retain the cover and form a seal. The ring is a circular modified "V" or "U" section channel, the ends of which are drawn together by means of a bolt and the periphery thus shortened, to develop the closure.


Less than truck load. An order which will not fill the minimum standard weight required for truck load freight rate, which usually means that the customer must pay an LTL freight rate.


(1) Extensions around the circumference of a lid which are crimped down to hold the lid securely in place against the body of the container. (2) A small indentation or raised portion on the surface of a plastic bottle, provided as a means of indexing the bottle for operations such as multi-pass decorating or labeling. (3) A metal fastener used for securing the top or bottom heads of a fiber drum, steel drum or metal pail to the side-wall.

Lug Closure

Interrupted thread finishes with the GPI finish number designations in the 2000 series.

Lug Cover

A cover for metal drum or pail, with extensions around the circumference that are bent down to hold the cover securely in place against the container body.

Lug Finish

Also called Lug/Twist. A glass container finish identified by intermittent horizontal tapering protruding ridges of glass that permit the specially shaped edges of the closure to slide between the protruding lugs and fasten securely with a partial turn. These lug finishes have the GPI designations in the 2000 series.


Intermittent thread design closure - commonly used for glass food containers.


A glass bottle, used occasionally for sparkling wines, having a capacity of two-fifths U.S. gallon. Some foreign magnums vary in capacity.


In Source Base, Material is one of the search criteria. It identifies the type of glass, plastic or metal used to make the item. If an item is made from various materials, i.e., fine mist pumps or trigger sprayers, the Material listed is the predominant material.

Material Distribution

A term which describes the variation in thickness of various parts of a plastic bottle, i.e., body, wall, shoulder, heel, base, etc. Material distribution is controlled by parison programming, temperature of the melted plastic, bottle geometry, blow up ratio, etc.

Matte Finish

A coating surface which displays no gloss when observed at any angle. Also referred to as a flat finish.


Medium density polyethylene. Slightly stiffer and has a higher melting index than low density polyethylene. Widely used in film.


Unit of radiation measurement.

Metallized Closure

Plastic closures with a surface deposit of aluminum coated with lacquers to render a decorative metallic effect.


The process of coating a plastic item with a thin layer of metal to give a gold, silver or other metal look. It is commonly used on closures used for cosmetic packaging.

Metric Conversions

Volume metric conversions include: 1 ounce = 29.57 or 8 drams, 8 ounces = 236.60 cc, 16 ounces = 473.20 cc, and 32 ounces = 946.40 cc. Liquid Capacity metric conversions include: 1 fluid ounce = 29.57 ml, 8 fluid ounces = 236.60 ml, 16 fluid ounces = 473.20 ml, 32 fluid ounces = 946.40 ml, 1 liter = 33.81 fluid ounces, 1 U.S. Gallon = 3.78 Liters, and 1 Imperial Gallon = 153.72 fluid ounces.


Transfer of a component of a material to a contacting material. In packaging, this is often the movement of an undesirable component of a packaging material into the product contained, or it can be loss of an important product component into the packaging material. Specified conditions of temperature, pressure and time should be provided.

Minimum Wall

A term designating the thickness of the wall (body) of a container. Usually specified as the minimum thickness allowable for the body of a container.


Millimeter. Metric unit of length equivalent to approximately 0.04 inch.


Also mould. (1) To shape plastic parts of finished articles by heat and pressure. (2) The cavity or matrix into which the plastic composition is placed and from which it takes its form. (3) The assembly of all parts that function collectively in the molding process.

Mold Number

The number assigned to each mold or set of molds for identification purposes, usually placed in that part of the container mold that forms the base of the container.

Mold Release

A chemical substance used to facilitate the freeing of a molded object from the mold in which it was formed. Unless the substance is cleaned from the object molded, it may cause adhesion problems at a later stage in manufacturing.

Mold Seam

A vertical line formed at the point of contact of the mold halves. The prominence of the line depends on the accuracy with which the mating mold halves are matched. Also known as parting line.


A relatively simple chemical which can react to form a polymer.


A test made to determine the bursting strength of a flat specimen of paper, paperboard, film, foil, plywood, corrugated fiberboard, solid fiberboard or other material.

Multi-Cavity Mold

A mold with more than one cavity impressions. Therefore, the mold produces two or more bottles per molding cycle.

Multi-Layer Bottle

A bottle which is co-extruded with two or more layers to contain oxygen-sensitive foods or industrial chemicals.

Narrow Mouth

Narrow mouth describes a container having an opening roughly one half the diameter of the container or smaller.


(1) The part of a container where the bottle cross section decreases to form the finish. (2) A round fitting in a can for the purpose of pouring the contents, covered by a closure.

Neck Bead

Usually a protruding circle on the neck of the bottle.

Neck Insert

Part of the mold assembly which forms the neck and finish. Sometimes called neck rings.

Neck Ring

That part of the mold equipment which forms the outside of the neck finish of a bottle.

Nesting Containers

Containers made with sloping sidewalls so they can be nested in each other when empty to conserve space.


A relatively cheap type of board made on a cylinder machine from waste newspaper stock.


The exact (or ideal) intended value for a specified parameter. Tolerances are specified as positive and negative deviations from this value.


Term applied in the medical device and pharmaceutical fields to products which have been tested and found to be free of a specified concentration of bacterial endotoxins (fever-causing agents). Typically evaluated using the USP in vivo Rabbit Pyrogen test or the in vitro LAL test.


(1) Mandatory embossing on the bottom of steel shipping containers indicating an un-reusable container. (2) Also used to indicate any non-reusable container. (3) A container, often required to be marked NRC, whose re-use is restricted by one or more regulatory agency.


The generic name for polyamides. A versatile family of thermoplastic resins that vary from relatively flexible products to tough, strong, and stiff materials. A key characteristic is resistance to oils and greases. Also outstanding resistance to fatigue and repeated impact. Water vapor transmission rate is high and gas permeability is moderate. Nylon films are widely used for meat and cheese packaging, boil-in-bags and pouches.


A particular shape. A rectangular figure having greater length than width, may have angle or rounded corners and parallel or nearly parallel sides.


Outside dimension. The outside dimensions of a container, package or part. In metal drums, it is the diameter over the rolling hoops.


Descriptive of material or substance which will not transmit light.


Oriented PET.

Orange Peel

An uneven surface somewhat resembling an orange peel.


The opening in a container through which product is dispensed.

Orifice Reducer

Plug or fitment with a controlled-diameter opening. When inserted in the I.D. of a bottle neck finish, it reduces the flow of product being dispensed.


A plastic container manufacturing variance in which a round container, when formed, does not remain round.


A particular shape. A container which has an elliptical cross section perpendicular to the major axis.


A secondary closure that fits over the primary closure or seal mechanism. It protects the primary closure from accidental dispensing. Overcaps are also used to enhance the design of a package.

Overflow Capacity

The capacity of a container to the top of the finish or to the point of overflow.


An outer container usually made of steel, wood or fiber, designed to enclose and protect one or more less durable inner containers.


A chemical reaction involving combination with oxygen to form new components.


Abbreviation for Polyethylene.


Abbreviation for polypropylene. See polypropylene.


Abbreviation for polystyrene. See polystyrene.


A line of bottles used primarily in the pharmaceutical industry. The bottles have large finishes with respect to bottle size, making bottles easy to pack.


Side wall collapse of a container occurring during aging or storage, caused by the development of a reduced pressure inside the container.


Also called a gob. A hollow plastic tube from which a container is blown in extrusion blow molding. In injection blow molding, it is the plastic shape formed by the core rod and parison mold that is transferred into the blow cavity for forming the final shape.

Particulate Matter

Unwanted foreign material which may become attached to or enveloped with a "clean" product. May be dust, debris, hair, or other particles. Generally 0.5 um or larger. May be airborne or "gross".

Parting Agent

A lubricant, often wax, used to coat a mold cavity to prevent the molded piece from sticking to it and facilitate its removal from the mold. Also called release agent.

Patent-Lip Vial

A tooled-neck vial with a square, rather heavy lip. See serum vial.


Also Polybutylene Terephthalate. In the polyester class of plastic resins. Good chemical resistance and clear color. Resistant to water and weak acids and bases at room temperature. Can be sterilized by EtO and autoclaving at temperatures up to 180 degrees Celsius.


See polycarbonate.

Performance Testing

The evaluation of a distribution package to determine its suitability to carry a packaged product through its distribution channel, without damage to the product, by simulating conditions within the transportation environment.


(1) The passage/diffusion of a gas, vapor, liquid, or solid through a barrier without physically or chemically affecting it. (2) The rate of such passage.


Polyethylene terephthalate. Known as thermoplastic polyester. Has the unusual ability to exist in either an amorphous or highly crystalline state. The crystalline state is necessary for extruding the material, and the amorphous state permits it to be oriented. Widely used in beverage bottles and in food trays designed for microwave and conventional ovens.


Polyethylene terephthalate G copolymer. Similar to engineering resins due to its strength and durability. However, its glass-like clarity, toughness and excellent gas-barrier properties make it an outstanding choice for storing biologicals. Tests have shown PETG to be biologically equivalent to, or better than, Type 1 borosilicate glass bottles for cell culture applications. In tests using a wide variety of cell lines, PETG was determined to be non-cytotoxic, and media stored in PETG bottles demonstrated proliferative and morphological characteristics comparable to control media. In fact, PETG bottles allowed growth of good monolayers directly on the surface of the bottle. PETG can be sterilized with radiation or compatible chemicals but cannot be autoclaved. Chemical resistance is fair.


Generic name for phenol-formaldehyde thermosetting plastic.

Pilferproof Seal

A seal that cannot be opened without partially destroying the cap or otherwise showing evidence of tampering.


In plastic bottle manufacturing, the bottom of the parison that is pinched off when the mold closes.


A very small hole in a plastic container, film, etc.


On a closure thread, the distance from one point to a similar point on the next adjacent thread.

Plastic Recycling Code

The recycling code on the bottom of each container consists of a triangle formed by three arrows, with a number in the center and distinguishing letters under the triangle. The number codes are: 1) PETE = polyethylene terephthalate, 2) HDPE = high density polyethylene, 3) V = vinyl, 4) LDPE = low density polyethylene, 5) PP = polypropylene, 6) PS = polystyrene, and 7) Other.


Chemical agent added to plastic compositions to make them softer and more flexible.


A suspension of a finely divided resin in a plasticizer.


(1) A type of closure which is designed to be inserted into the opening of a container. May be held by friction or by screw threads. (2) A threaded closure part for metal drums. Usually marketed with a receiving flange which is fastened to the drum body or head by welding or other method. (3) A bung. (4) The removable top furnished with certain types of cans.

Plug Seal

A narrow non-flexible protrusion molded into a closure which fits into the bottle neck during normal bottle sealing operations. To be effective, specific inside dimensional tolerances are required for both the closure plug and the bottle neck finish. Plug seals are most commonly seen on snap-on style closures.


Pantone Matching System. A series of standard colors commonly used by package designers and manufacturers. These are published by Pantone, Inc. Communication of specified colors can be made with a code number on a tear-away chip taken from the book.

Pock Marks

Irregular indentations on the surface of a blown container caused by insufficient contact of the blown parison with the mold surface. They are due to low blow pressure, air gas entrapment, or moisture condensation on the mold surface.

Polyallomer (PA)

Polyallomer is an essentially linear copolymer with repeated sequences of ethylene and propylene. It combines some of the advantages of both polymers. Polyallomer is autoclavable, and offers much of the high temperature performance of polypropylene. It also provides some of the low temperature strength and flexibility of polyethylene.


Polycarbonate is window-clear, amazingly strong, and rigid. It is autoclavable, nontoxic and the toughest of all thermoplastics. PC is a special type of polyester in which dihydric phenols are joined through carbonate linkages. These linkages are subject to chemical reaction with bases and concentrated acids, cydrolytic attack at elevated temperatures (e.g. during autoclaving), and make PC soluble in various organic solvents. For many applications, the transparency and unusual strength of PC offset these limitations.


A thermoplastic material composed of polymers of ethylene. It is normally a translucent, tough, waxy solid which is unaffected by water and by a large range of chemicals. There are three general classifications: low density, medium density and high density.


A high molecular weight organic compound, natural or synthetic, whose structure can be represented by a repeated small unit, the polymer; i.e., polyethylene, rubber, cellulose. Synthetic polymers are formed by addition or condensation polymerization of monomers. If two or more monomers are involved, a copolymer is obtained. Some polymers are elastomers, some plastics.


Polyolefins are high molecular weight hydrocarbons. They include low-density and high-density polyethylene, and polypropylene. All are break resistant, nontoxic, and non-contaminating. These are the only plastics lighter than water. They easily withstand exposure to nearly all chemicals at room temperature for up to 24 hours. Strong oxidizing agents eventually cause embrittlement. All polyolefins can be damaged by long exposure to ultraviolet light.


Polypropylene is similar to polyethylene, but each unit of the chain has a methyl group attached. It is translucent, autoclavable, and has no known solvent at room temperature. It is slightly more susceptible than polyethylene to strong oxidizing agents. It offers the best stress-crack resistance of the polyolefins. Products made of polypropylene are brittle at ambient temperature and may crack or break if dropped from benchtop height. Used in film, in sheet and for molded rigid containers.

Polypropylene Alloy

Abbreviation PPAL. Physical blend of polypropylene and high density polyethylene resulting in characteristics common to both resins, with additional barrier to migration of essential oils.


A thermoplastic material derived from the polymerization of styrene (vinyl benzene); non-toxic, tasteless, odorless, good general dielectric properties; excellent water and weather resistance and resistant to most foods, drinks, etc., with the exception of essential oils, gasoline, turpentine, which will harm the material. Poor impact strength.


A polymer containing a specific sulfone linkage. These thermoplastic materials exhibit exceptionally high temperature and low creep properties.

Polyvinyl Acetate

A thermoplastic material prepared by the polymerization of vinyl acetate alone. A colorless solid with good resistance to water and concentrated acids and alkalies.

Polyvinyl Chloride

Abbreviation PVC. See additional info under PVC. Rigid, natural straw color, transparent, good barrier properties with excellent resistance to oxygen permeation, excellent resistance to oils and fair impact resistance.


To fill containers after labeling instead of labeling them after filling and closing, which is called pre-fill.

Pourout Finish

A glass container finish with an undercut immediately below the top, so designed to facilitate pouring without dripping. It is used primarily by prescription and other drug and chemical companies.


Polypropylene alloy. Physical blend of polypropylene and high density polyethylene resulting in a material with characteristics common to both resins, with an additional barrier to the migration of essential oils.


To fill containers before applying labels to them.


An injection-molded parison which is blow molded by a second step to form a plastic bottle.

Pressure Sensitive Label

A die cut label coated with a pressure-sensitive pre-applied tacky adhesive and requiring pressure only to adhere it to a package or product.

Prototype Mold

A simplified mold construction often made from a light metal casting alloy or from an epoxy resin to provide actual molding for evaluation and testing prior to production mold consideration.


Injected molded two piece dispensing closure. Closure is opened by pulling up and closed by pushing down the spout. Overcaps are optional.


In plastic bottle manufacturing, the forcing out of one color or one resin type by another from an extruder or cylinder prior to molding the new color or resin.

Push Up

The recessed area on the bottom of a container designed to allow a stable bearing surface on the outside edge and prevent rocking.


Polyvinyl chloride. A thermoplastic material composed of polymers of vinyl chloride, a colorless solid with outstanding resistance to water, alcohols, and concentrated acids and alkalines. Compounded with plasticizers, it yields a flexible material superior to rubber in aging properties.

Radiation Sterilizing

The industrial process that kills microoganisms by exposure to high levels of ionizing energy. Most commonly used are gamma rays from cobalt 60. Electron-beam x-ray energy is also used.


A small depressed cavity (detent) in the base of the bottle to act as a guide in positioning the bottle in the decorating machine for application of decoration.


Shipping container in which empty unit containers are received and intended to be used as shipping containers for the product packaged in the unit containers.


A method used to trim and size the inside of a plastic bottle neck finish. A special rotating cutting tool trims the sealing surface smooth and simultaneously reams (bores) the bottom opening to desired size.

Recessed Panel

A container design in which the flat area for labeling is indented or recessed.


Packaging materials that may be processed for reuse by a series of changes or treatments, but not necessarily for their original use.


In plastic bottle manufacturing, ground material from flash and trimmings which is usually blended with virgin material and remolded.

Removal Torque

The turning or twisting force required to remove a lug cap, screw cap, or twist off crown. Usually expressed in terms of "inch pounds" and measured by means of a reliable torque meter.


Any of a class of solid or semi-solid organic products of natural or synthetic origin, generally non-crystalline and of high molecular weight with no definite melting point. Most resins are polymers.

Reverse Taper Closure

A closure silhouette characterized by the top of the closure being larger in diameter than the open end.


RNase, an enzyme that breaks down RNA, is a contaminant that interferes with nucleotide research. Plastic containers may be manufactured RNase free, but this a difficult to certify. No analytical tools exist to test for low RNase levels.


A container with a bulged or deformed bottom, causing the container to rock when in an upright position.


Glass and polyethylene rods are used particularly in the drug and cosmetic industries. One of the most common is a balled-end rod for touch applying medicines.


Roll-on pilferproof aluminum closure.


Regular slotted container. A rectangular three dimensional shipping container, made of either solid fiberboard or of corrugated fiberboard. Outer flaps meet. Inner flaps do not meet unless length and width happen to be the same.

Rust Inhibitor

Also RI. A chemical agent, incorporated in a compound applied to a metal surface to prevent or reduce rust or corrosion.


Styrene acrylonitrile. Thermoplastic copolymer with good stiffness, scratch, chemical and stress-crack resistance.

Similar to general purpose polystyrene except for improved impact resistance and barrier properties; increased rigidity and UV stability; natural straw color; transparent.

Screw-Thread Vial

A vial with a very short neck and an outside screw-thread finish.

Sealing Surface

That portion of a glass or plastic container finish which will make contact with the interior liner of the cap to affect the seal.


Made in one piece without a joint.

Serum Vial

A vial having a neck with a relatively small opening to receive a rubber plug stopper and aluminum seal.


Shape is one of the search criteria. In the Glass and Plastic product types, Shape refers to the shape of the bottom of the container. Shape is not a search criteria in the Closure product type.


A line of glass containers (used by drug and chemical companies) that was designed to give the packer specific advantages on label space, maximum size, appearance and easy pouring, combining the best features of Boston Round and F-style containers.

Shell Vial

A cylindrical container, usually made of glass, characterized by having straight sides, being neckless, and having a flat bottom. Made by sealing one end of a glass tube of appropriate diameter and length.


Solvents leaching through a plastic container.


(1) That part of a container between the main body and the neck. (2) That portion of a closure immediately adjacent to and including the corner where top and skirt join. (3) In a can, an off-set on a straight side to act as a stop or support.

Shrink Labels & Bands

Pre-decorated plastic sleeves that are slipped over the container and heated until they conform to the surface of the container. Same principle as the sleeve label, but superior for odd and small shapes.

Sifter Fitment

A plastic or metal component of a package designed to allow shaking out of dry products, as with a table salt shaker. Snaps over bead, with metal or plastic cap applied over the fitment.


In SourceBase, Size is one of the search criteria.

In the Glass and Plastic product types, Size refers to the nominal capacity of a bottle or jar. The nominal capacity is the intended capacity of the container. It is expressed in fluid ounces (oz), gallons (gal), milliliters (ml), drams, etc.

In the Closure product type, Size refers to the outside diameter of a bottle or jar's neck finish, including the threads. The size is usually designated in millimeters (mm).


The vertical part of a closure below the shoulder.

Sleeve Label

A decorated, plastic label made into a tubular form that fits over and on plastic bottles.

Slip Cap

(1) A metal closure with indentations on its sides to make a friction fit on a vial with a slip-cap finish. (2) A closure made of soft material such as polyethylene or rubber, without threads, to be pushed over the tip or neck of a container and held in place by friction.

Snap Top

The most prevalent hinged closure. This closure features a spud and orifice design that is sanitary and self cleaning to prevent clogging. It is available in a wide range of orifice sizes. The snap type can also be designed with an off center spout to direct product flow. The pour spout can be easily lined with a variety of heat sealed materials to ensure product freshness.

Space Saver

Refers to any pharmaceutical package such as the shelfline or blake style bottle which, because of it rectangular shape, takes up less storage space on the druggist's shelf.

Spin Welding

A process of fusing two objects together by forcing them together while one of the pair is spinning, until frictional heat melts the interface. Spinning is then stopped and pressure held until they are "frozen" together.

Spray Frosting

The technique of spray coating a glass container to create a frosted, matte translucent appearance.


In plastic bottle manufacturing, silkscreen decoration. Also S/S.


An ingredient used in the formulation of some plastics, especially elastomers, to assist in maintaining the physical and chemical properties of the compounded materials at their initial values throughout the processing and service life of the materials.

Stacker Cap

A closure designed specifically to nest with the bottom plate of a container to facilitate the stacking of filled containers on top of each other.


Single trip container.


A decoration consisting of a system of closely spaced small raised dots on the outer surface of a container or closure.


A solid, cork-shaped, ground-to-fit plug used to seal some bottles.

Storage Life

The period of time during which a product can be stored under specified temperature conditions and remain suitable for use. Sometimes called shelf life or working life.

Stress Cracking

The susceptibility of a thermoplastic article to cracking or crazing under the influence of certain chemicals and stress. Frequently accelerated by the environment to which the plastic is exposed. The stresses which cause cracking may be present internally or externally or may be combinations of both.


In plastic bottle manufacturing, a longitudinal line in the parison or bottle due to a disturbance in the melt path.

Strip Mold

Mold action in the manufacture of closures: After the injection cycle is completed, the cavity is removed and the stripper sleeve moves forward forcing the closure to flare and strip over the core.


Style is one of the search criteria. In the Glass and Plastic product types, Style can refer to standard industry names, such as Cylinder, Boston Round, F-Style, Modern Round, Wide Mouth (W/M) Jar, etc. If a name is not standard industry-wide, Style refers to the sides of the bottle, i.e., straight sided, tapered, etc. In the Closure product type, Style designates standard industry names. If a closure has threads, the Style is Continuous Thread. Other Styles include Dispensing, Child Resistant Closure (CRC), etc.

Styrene Acrylonitrile

Similar to general purpose polystyrene except for improved impact resistance and barrier properties; increased rigidity and UV stability; natural straw color; transparent. Also see SAN.

Surface Treating

Any method of treating the surface of a plastic item to accept inks, paints, adhesives and chemical, flame and electronic treating.


Abbreviation for tight head. Used by drum and pail manufacturers to indicate that the lid is a structural component of the drum or pail, instead of a separate part.


A form of liner usually of glassine that is applied over and bonded to a waxed under-liner. When cap is removed from glass, the tacseal liner adheres to the glass lip as a security-type liner.

Tamper-Evident Band

(1) A secondary closure made of aluminum, steel, plastic, tape or film to be applied over a primary cap-closure of a rigid container, and designed to require tearing off by manual effort before the container is opened or contents removed. Purpose is to reveal any tampering with the primary closure. (2) Also a perforated extension of tamper-evident closures.

Tamper Resistant Seal

A seal that cannot be opened without partially destroying the cap or otherwise showing evidence of tampering.

Tear Strip

A narrow ribbon of film, cord, etc., usually incorporated mechanically in the wrapper or over wrap during the wrapping operation or imbedded in a carton to facilitate opening of the package. The scored strip on a key-opening can. Tear tape.

Tear Tab

An extension of the tearing strip on a package to permit easy grasping with the fingers.

Teflon FEP

Teflon FEP is translucent, flexible and feels heavy because of its high density. It resists all known chemicals except molten alkaki metals, elemental fluorine and fluorine precursors at elevated temperatures. It should not be used with concentrated perchloric acid. FEP withstands temperatures from -270 degrees C to +250 degrees C and may be sterilized repeatedly by all known chemical and thermal methods. It can even be boiled in nitric acid.

Teflon PFA

Teflon PFA is translucent and slightly flexible. It has the widest temperature range of the fluoropolymers from -270 degrees C to +250 degrees C, with superior chemical resistance across the entire range. Compared to TFE at +277 degrees C, it has better strength, stiffness and creep resistance. PFA also has a low coefficient of friction, outstanding anti-stick properties and is flame resistant.

Tefzel ETFE

Tefzel ETFE is white, translucent and slightly flexible. It is a close analog of the Teflon fluorocarbons, an ethylene tetrafluoroethylene copolymer. ETFE shares the remarkable chemical and temperature resistance of Teflon TFE and FEP, and has even greater mechanical strength and impact resistance.


The generic term is heat transfer labeling. Process in which a label is applied to a container by heating the label and the surface of the bottle. The heating of the label activates the adhesive on it. After application, the labeled container is flamed to set the label. Used for decorating plastic bottles, glass bottles, and folding cartons.

Thermal Stress Crack

Crazing and cracking of some thermoplastic resins which result from over-exposure to elevated temperatures.


A plastic that will repeatedly soften when heated and harden when cooled. Typical packaging thermoplastics are polystyrenes, polyethylenes, acrylics, vinyls, and nylons.

Thermoplastic Resin

A resin having the property of becoming soft upon application of heat, rigid at normal temperature, and plastic on each reapplication of heat.


(1) A material that will undergo or has undergone a chemical reaction by the action of heat, catalysts, ultra-violet light, etc., leading to a relatively infusible and cross-linked state. Typical of the plastics in the thermosetting family are aminos (melamine and urea), polyesters, alkyds, epoxies, and phenolics. (2) A material which hardens when heated and does not again soften when reheated.


The indented curved formed section of the cap on the skirt that engages and matches the thread of the container for screw fit purposes. The thread may be continuous or interrupted.


In closure applications, refers to tin-plated steel. It is sheet steel, usually of special formula and temper, coated on both sides with a controlled thickness of pure tin.

Tinplate (electrolytic)

Black plate that has been coated on both sides by electro-deposition of commercially pure tin, which is then usually melted to improve the appearance and properties of the tinplate. Coating weights available are generally lower than on hot-dipped. Commonly used weights are: 0.20, 0.25, 0.50, 0.75 and 1.00 pound tin per base box. Tinplate numbers refer to these weights. Lower weights of 0.05, 0.10, and 0.15 are also possible for some applications.




A specified allowance for deviations in weighing, measuring, etc., or for deviations from the standard dimensions or weight.

Top Load

The amount of weight bearing on the top of a container. The term is sometimes used to indicate the maximum load the container will bear without becoming distorted.

Torque -- Removal

The rotational force with which a threaded closure is removed from a bottle finish. It defines the amount of rotational force necessary to loosen, open, or remove the closure. A properly designed package should have a removal torque range appropriate for its intended use and the consideration of any requirements for child resistant or tamper evident closure needs.

Torque -- Stripping

The application torque which is sufficient to cause the closure and/or bottle finish to distort and override the matching closure/bottle threads, resulting in loose caps, no seal, or package component deformation.

Torque - Application

The rotational force with which a closure is applied to a bottle finish during capping. It affects seal integrity and tightness between bottle and closure. A properly established application torque will provide sealing integrity under expected conditions of temperatures, vibration, humidity, and shock.

Torque Tester

A type of torque meter used for measuring removal torque of screw caps, lug caps, or twist-off crowns. Can also be used to apply screw or lug caps to a known predetermined tightness.


Thermoplastic elastomer.

Transfer Bead

A projecting bead on the outer surface of some glass containers, usually just below the finish, to provide a surface of engagement for the jaws of handling devices during manufacture.


Descriptive of a material or substance transmitting some light, but not clear enough to be seen through.


Descriptive of a material or substance capable of a high degree of light transmission (e.g., glass). Some polypropylene films and acrylic moldings are outstanding in this respect.

Tubular Glass

Containers made from preformed hollow glass tubes. The tubes are cut into desired length, and by heat and pressure they are shaped into the desired configuration. Unlike blown glass, tubular items do not require molds.


An injected molded two piece dispensing closure. It requires that the turret "spout" be lifted with a finger to open and dispense.

Type I Glass

A borosilicate glass which releases the least amount of alkali. It is commonly used for pharmaceutical or fine chemical products that are sensitive to PH changes.

Type II Glass

A soda lime glass (Type III) that has been de-alkalized by treating the interior surfaces to eat away the alkali on or near the glass surfaces. The undesirable characteristic of Type II Glass is that the treating etches the surface, causing a frosted appearance.

Type III Glass

A soda lime glass and the most common in use. Type III is compatible with most items: food; beverages; common chemicals; etc.


Zone of invisible radiations beyond the violet end of the spectrum of visible radiations. Since UV radiation is a shorter wavelength than visible, it is of higher energy that is sufficient enough to initiate the chemical reactions that degrade most plastics.

UN Number

The four-digit number assigned by the United Nations Committee of Experts on the transport of dangerous goods. These numbers identify a particular group of substances.

Unit Dose Packaging

A package which contains one discrete dosage form, i.e., one tablet, one capsule, one 2 ml quantity of liquid, etc. A unit package consists of the unit quantity, protective wrapping, cushioning, and identification marking, up to but not including the shipping container. Single dose unit packaging is used for foods, drugs, cosmetics, medical devices and some industrial products.

Unit Mold

A simple mold which comprises only a single cavity without further mold devices, and is used for the production of sample containers.

Unitized Load

A load in which all the containers or articles which may consist of two or more units combined by interlacing or, more commonly, bound together by means of tension strapping, plastic shrink or stretch films.

Unscrewing Mold

Mold action in the manufacture of closures. After the injection cycle is completed, the mold cavity is removed. The core then begins to rotate, literally unscrewing the core from the closure, as a stripper sleeve moves forward to eject the closure.

UPC Symbol

Universal product code. A 10 digit, all numeric code which uniquely identifies a product. The first 5 digits, called the manufacturer identification number, identify each manufacturer or organization controlling the label of the product. The second 5 digits, called the item code, identify individual items within the companies and are assigned by the manufacturer or organization controlling the label of the product.


Generic name for urea-formaldehyde. A thermosetting compound used to fabricate light colored plastic closures as opposed to phenol which is for dark closures.

UV Stabilizer

Any chemical compound which, when mixed with a thermoplastic resin, selectively absorbs UV rays and minimizes chemical and/or physical changes that may be engendered by UV.


A small non-flexible v-shaped ring molded into a closure so that the v makes contact with the sealing surface (land) of the container's finish during normal sealing operations. The V-Seal requires compression to be effective. Most commonly used for sealing tubes.

Vacuum Closure

Any closure equipped with a liner capable of holding a vacuum.

Valve Cap

A closure that includes a valve to regulate the flow of the product from the container.

Valve Seal

A Valve Seal finish requires a closure mechanism that will seal a container on the inner portion of the container wall, at the top of the finish.


In a mold, a shallow channel or minute hole cut in the cavity to allow air to escape as the material enters and to facilitate ejection of the molded part from the cavity.


Informal generic term for any of the vinyl resins, or for film, or other product made from them.

Virgin Material

A material or liquid that has not been subjected to use or processing other than that required for its original manufacture.

Viscose Band

A secondary closure or seal made of regenerated cellulose, applied in a wet state over the cork, metal or plastic cap that forms the primary closure, and then shrunk tight by drying. It is used to prevent tampering, to dress up the package, to provide brand identification, to aid the primary closure in preventing escape of products, to prevent cap from becoming unscrewed, etc.


Also known as displacement or capacity. (1) The amount of water displaced by a model of a container; used to estimate its capacity. (2) The amount of product a container is designed to hold, i.e., up to the fill-point of the container. (3) Also, the overflow capacity, i.e., amount of product a container will hold when filled to overflowing.


The central portion of a container which has a smaller cross-section than the adjacent areas.

Water Vapor Perm.

The property of a material that permits water vapor to pass through its structure. This property has measurable values that can be determined under specified conditions of time, temperature and the water vapor pressure differential between two sides of a material or between two sides of material or between the inside and the outside of a container.

Well Cap

A closure for a container in which there is an interior recessed opening into which an applicator may be affixed.

White Room

A filling or compounding room where extreme measures are taken to assure product cleanliness. Also called clean room.

Wide Mouth

Wide mouth describes any container having an opening roughly half of the diameter of the container to almost the full diameter size of the container.

Wide Mouth Finish

A finish on a container, the diameter of the finish being large relative to the diameter of the body.


Water vapor transmission rate. The actual rate of water vapor transmission used to compare water vapor barrier, wrapping, or container materials. Usually expressed in grams of water passing through 1 square meter of material in 24 hours at 100 F and 90% relative humidity. Rate may also be expressed in different units as grams per 100 square inches per 24 hours, etc., or under different conditions of temperature and relative humidity.