Warning: Use of undefined constant PLASTICS - assumed 'PLASTICS' (this will throw an Error in a future version of PHP) in /home/q4hi4wldq8dy/public_html/plastics_glossary.php on line 1

Warning: Use of undefined constant GLOSSARY - assumed 'GLOSSARY' (this will throw an Error in a future version of PHP) in /home/q4hi4wldq8dy/public_html/plastics_glossary.php on line 2


Just select text on the page and get instant translation from Google Translate!

Google Translate Client


Aesthetic Fill - Filling to a specific level in a clear package where the fill level is visible.

Aesthetics - The sum total of the visual response to the beauty of an object. Elements of aesthetics may include: color, shape or particular features of the object.

Aging - The physical and/or chemical change of a material with respect to time, under defined environmental conditions, leading to improvement or deterioration of properties.

Amber - A chromatic (brown) color of glass or plastic containers. It is used principally to protect the contents of the container from exposure to light.

Antioxidant - A chemical substance added to a plastic resin to minimize or prevent the effects of oxygen attack on the plastic, e.g., yellowing or degradation. Chemical attacks by oxygen can render a plastic brittle or cause it to lose desired mechanical properties.

Anti-static Agent - A chemical substance applied to the surface of a plastic article or incorporated in the plastic from which the article is made. The anti-static agent renders the surface of the plastic article less susceptible to the accumulation of electrostatic charges which attract and hold fine dirt or dust on the surface of the plastic article.

Application Torque - The torque force, measured in inch-pounds, required to screw a closure onto a container.

Applicator Cap - A closure designed to apply the contents of the container.

Barrier - Protection from deterioration or admittance of moisture or other elements (such as oxygen and other gases) through package material.

Barrier Coat - A surface coating to improve permeation resistance and/or protect the container from scuffing.

Barrier Resins - A group of resins specially formulated to resist the transmission of oxygen, water, solvents, essential oils, etc.

Base - The bottom of the bottle or jar, often marked with a recycle code and indentations used during filling and labeling.

Bead - On Hinge-Guard/J-Cap style neck finishes, the collar of plastic beneath the neck area that snap-on caps rest against.

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, by using air pressure, the parison is forced to assume the shape of the cavity. The air pressure is introduced through the inside of the parison. The air pressure forces the plastic against the surface of the mold that defines the shape of the container.

Blow Pressure - The pressure required to form the parison or preform into the shape of the mold cavity, in a blow molding operation.

Body - The principal part of a container, usually the largest piece containing the sides. In bottles, the body is the main portion of the bottle without the neck.

Bottom Plate - That part of the mold which contains the heel (base radius) radius and the "push-up ' of the container to be formed.

Butterfly Hinge - Flexible (i.e., living) hinge used in joining the cover to the main body of a flip top dispensing closure. Superior hinge for impact resistance.

Buttress Thread - A design of thread profile (cross section) which takes the form of a truncated triangle or slight modification of that form. It is usually positioned so 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. It is designed to withstand maximum force in one direction only.

C.A.D. - Computer Assisted Design

C.A.M. - Computer Aided Molding

Capacity - (1) The amount of space provided inside a container for a given amount of product. (2) The total amount of volume inside the container. The latter is more correctly called the overflow capacity.

Cavity - The part of the mold that contains the reverse image of the product being formed.

Clarity - Freedom of haze or cloudiness in a plastic material.

Closure - A devise used to seal off the opening of the bottle to prevent the loss of its contents.

Color Concentrate - A measured amount of dye or pigment incorporated into a predetermined amount of plastic. This pigmented or colored plastic is then mixed into larger quantities of plastic material used for molding. The "concentrate" is added to the bulk of plastic in measured quantity in order to produce a precise, predetermined color of the molded bottles.

Concentricity - The characteristic of circles or circular cylindrical surfaces of different radii having a common center.

Continuous Thread (CT) Finish - An uninterrupted protruding helix on the neck of a bottle to hold a screw type closure.

Copolymer - A material whose chemical structure is made of long chains of two differently structured chemical units (Monomers) which repeat a more or less regular pattern in the chain.

Core - The part of a mold that allows the internal shaping of a product such as the internal threads of a cap.

CR - Child Resistant, indicates that a package will pass a test protocol administered by the U.S. Consumer Product Safety Commission.

Cycle - The complete, repeating sequence of operations in a process. In molding, the cycle time is the period of elapsed time between a certain point in one cycle and the same point in the next.

De-flashing - Any technique or method removing excess unwanted material from a molded article. Specifically, the excess material is removed from places on the article where parting lines of the mold that formed the article may have caused the excess material to be formed.

Density - Weight per unit volume of a substance. Density is expressed in grams per cubic centimeter, pounds per cubic foot, etc.

Dimensional Stability - The ability of a material to maintain its shape under given processing or use conditions.

Discoloration - Any change from the original color. Discoloration is often caused by overheating, light exposure, irradiation, or chemical attack.

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.

Drug Master File - A Drug Master File (DMF) is a submission to the Food and Drug Administration (FDA) that may be used to provide confidential detailed information about facilities, processes, or articles used in the manufacturing, processing, packaging, and storing of one or more human drugs.

"E" Dimension - The outside diameter of neck on a threaded bottle neck (finish). The diameter of the neck (finish) is measured across the root of the threads.

Environmental Stress Cracking - The susceptibility of a plastic part to crack or craze under the influence of certain chemicals, stress or other agents.

Extrusion - The compacting of a plastic material and forcing of it through an orifice in more or less continuous fashion.

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

Finish - The plastic forming the opening of a container and shaped to accommodate a specific closure.

Fitment - A device used as part of a closure assembly to accomplish a certain purpose such as, dropper, sprinkler, powder shakers, etc.

Flame Treating - A method of rendering inert thermoplastic objects receptive to inks, lacquers, paints, adhesives, etc. The object is bathed in an open flame to promote oxidation of the surface of the article.

Flash - The extra plastic attached to a molding along the parting line. The flash must be removed before the parts can be considered literally finished.

Flexibility - The property of a material that will permit its being bent or twisted without breaking.

Flip Top - A two-piece closure system where both pieces are typically attached by a living hinge. One half provides the threads for attachment to a bottle, tube or jar and an orifice for dispensing the product while the other half provides the closure mechanism, usually a pintel that snaps audibly into the orifice.

Fluorination - Is an extra process in which a thermoplastic article (container or closure) is exposed to fluorine gas. The fluorine substitutes with some hydrogen atoms in the polymer chain creating a barrier and surface enhancement. Benefits include improved barrier properties and reduced solvent absorption and permeation.

Gas Permeability - the ability of a gas or other volatile substance to penetrate a material. Materials that will allow significant passage of gases are said to be permeable, while materials that resist or stop the passage of gases are said to offer gas barrier properties.

Gaylord - a term used to designate a very large carton (i.e., 45x 33x 51) that will fit one per pallet. There are various sizes depending on the pallet and the customer requirements.

"H" Dimension - the height of the bottle finish measured from the sealing surface, in a line parallel to the axis of the finish and tangent to the threads on the finish, down to a point where the line intersects the body (shoulder) of the container. The inside height of the closure measured from the bottom of the closure, in a line tangent to the threads of the closure and terminating at the inside, top of closure.

Hardness - the resistance of a material to compression and indentation.

Haze - a cloudy or foggy appearance in a normally transparent plastic.

Head Space - the space between the level of the contents in the neck of a bottle and the closure. It is intended to furnish space for expansion of product due to heat or other action after packing. Head space may also refer to the amount of space in a corrugated shipper carton filled with plastic bottles or jars.

Heel - the part of a bottle between the bottom bearing surface and the side wall.

Heavy gram bottles - bottles blown from a parison or preform to a size that is relatively small for the parison's/preform's capacity. The result is a bottle with greater wall thickness, because more plastic has been distributed over a smaller bottle shape.

Hermetic seal - a seal that will exclude air and will be gas tight at normal temperatures and atmospheric pressures.

High-density polyethylene (hdpe) - a rigid, tough and strong resin of natural milky color. Hdpe has very good stress crack resistance as well as high impact and melt strength. With hdpe it is easy to add color.

Hygroscopic - tending to absorb moisture.

"I" dimension - a specified minimum diameter inside the bottle neck. A minimum diameter is specified to allow sufficient clearance for filling tubes to enter the bottle neck easily.

"I.D." - an abbreviation for inside diameter.

Impact Resistance - relative susceptibility of plastics to fracture by shock. Impact resistance is indicated by the energy expended by a standard pendulum type impact machine in breaking a standard specimen in one blow.

Indented label panel - when the diamter of the label panel area on a bottle is smaller than the diameter of the bottle immediately above and below the label panel area.

Injection blow molding - a blow molding process in which the parison to be blown is formed by injection molding.

Injection molding - a molding procedure whereby a heat-softened plastic material is forced from a cylinder into a relatively cool cavity giving the article the desired shape.

Injection molds - a mold into which a plasticated material is introduced from an exterior heating cylinder.

J-cap finish (also called hinge-guard) - flexible (i.e., living) hinge used in joining the cover to the main body of a flip top dispensing closure. Consumers open a j-cap closure by removing a strip of plastic holding the top of the closure to the base of the closure, leaving a hinged, snap-top closure mechanism. This type of closure can also provide tamper evidence.

"l" style thread - a type of thread contour (cross-section) roughly trapezoidal in outline. The outermost part is radiussed a "general purpose" thread contour designed for use with metal or plastic closures.

Label panel - the flat area of the bottle's body where a label can be applied. Some of B&C Plastics Ltd.'s bottles feature indented label panels.

Light resistance - the ability of a plastic material to withstand exposure to light, usually sunlight or the ultraviolet part of the light spectrum, without change of color or loss of physical and/or chemical properties.

Living hinge - integral hinge made of flexible plastic.

Lug closure - a screw-type closure where the thread is interrupted rather than continuous. The closure is affected by a short camming action. One advantage is that application is very fast, since the closure needs only a few degrees of rotation. In contrast, a normal continuous thread closure might require 360 degrees or more of rotation to affect a seal.

Mil - a unit of measurement equal to .001 inch.

Minimum wall - a term designating the minimum thickness of the wall of a bottle.

Moisture vapor transmission rate (mvtr) - the rate at which water vapor permeates through a plastic film or bottle wall at a specified temperature and at relative humidity.

Mold - the cavity or matrix into which the plastic composition is placed and from which it takes its form.

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.

Mouth - the opening at the top of a bottle or jar.

Multi-layer bottle - a bottle that is co-extruded with two or more layers to contain oxygen sensitive foods or industrial chemicals.

Narrow mouth - a finish of a plastic container in which the diameter is small relative to the diameter of the body.

Neck - the part of a container where the shoulder cross section area decreases to form the finish.

Neck finish - the plastic surrounding the opening of a bottle shaped to accommodate a specific closure. It's the portion of the neck that carries the threads, lugs or friction fit members to which the closure is applied, and includes the sealing surface and sealing bead; generally, the whole portion above the transfer or pry-off bead. B&C Plastics Ltd. makes continuous thread (c/t) necks for twist-on caps, and hinge-guard (j-cap) necks for snap-on caps.

Neck insert - part of the mold assembly that forms the neck and finish. Sometimes called the "neck ring."

Neck ring - that part of the mold equipment that forms the finish of a bottle.

Offset printing - a printing technique in which ink is transferred from a reservoir to a printing plate. For the ink printing plate, the image is printed on a cylindrical rubber roll (blanket) and then to the object to be printed.

Opaque - a term describing a material or substance which will not transmit light.

Orientation - the alignment of the crystalline structure in polymeric materials so as to produce a highly uniform structure. Orientation can be accomplished by cold drawing or stretching during fabrication.

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

Packer - packers are wide-mouth bottles typically used for pills, capsules and tablets. B&C Plastics Ltd. makes several different styles of packers, including rounds (also called pharma rounds), oblongs (with square bases) and apothecary styles (with concave shoulder areas) in both pet and hdpe.

Paneling - distortion, side wall collapse of a container occurring during aging or storage. Paneling is caused by the development of a reduced pressure inside the bottle.

Parison - the extruded hot plastic tube that will be placed in a high-density polyethylene mold to be inflated into a bottle or other hollow form.

Parting line - the mark on a bottle where two halves of a mold meet in closing.

Permeation - the extent to which a gas or water vapor passes through a plastic film or container.

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

Pet (polyethylene terephthalate) - known as thermoplastic polyester. Pet has the unusual ability to exist in either an amorphous or highly crystalline state. The crystalline state is necessary for extruding the material. The amorphous state permits it to be oriented.

Pinch-off - a raised edge around the cavity in the mold, which seals off the part and separates the excess material as the mold closes around the parison in the extrusion blow molding operation.

PLA - polymerized lactic acid - a corn-based resin made by natureworks pla that requires significantly less energy to mold into plastic containers.

Plastic memory - the tendency of plastics to return to their original molded form.

Plasticizer - a material added during the manufacturing process to increase flexibility.

Plasticize - to soften a material and make it plastic or moldable by means of a plasticizer or the application of heat.

Polyethylene - a thermoplastic material composed of polymers of ethylene. It is normally a translucent, tough, waxy solid unaffected by water and a large range of chemicals.

Polypropylene - a tough, light-weight rigid plastic made by the polymerization of high-purity propylene gas in the presence of an organometallic catalyst at relatively low pressures and temperatures.

Polystyrene - a water-white thermoplastic produced by the polymerization of styrene (vinyl benzene).

Polyvinyl chloride (pvc) - a thermoplastic material composed of polymers of vinyl chloride. Pvc is a colorless solid with outstanding resistance to water, alcohols, and concentrated acids and alkalies.

Pour-out finish - a bottle finish having uniform undercut lips as a dealing surface, to facilitate pouring without dripping.

Preform - used in blow molding processes. Heat-softened polymer (such as pet) is formed into a shape similar to a thick test tube with neck threads. The tube is subsequently heated and inflated while inside a blow mold to create the shape of the desired bottle or jar.

Programming - the extrusion of a parison which differs in thickness in the length direction in order to equalize wall thickness of the blown container. It can be done with a pneumatic or hydraulic device which activates the mandrel shaft and adjusts the mandrel position during parison extrusion (parison programmer, controller, or variator). It can also be done by varying extrusion speed on accumulator-type blow molding machines.

Prototype mold - a simplified mold construction often made from a light-casting alloy or from epoxy resin in order to obtain information for the final mold or part design.

Push up - the contour of the bottom of the plastic container designed in such a manner as to allow as even bearing surface on outside edge and prevent the bottle from rocking.

Regrind - a thermoplastic from a processor's own production that has been cleaned and reground.

Resin - any class of solid or semi-solid organic products of natural or synthetic origin, generally of high molecular weight, with no definite melting point. Most resins are polymers.

Runner - in injection molding, one of the passages that take plastic melt from the injection point (sprue) and distribute it to the various cavities in a multi-cavity mold.

"S" dimension - locates the position of the bottle thread with respect to the sealing surface. The "s" dimension is the vertical distance from the sealing surface to the intersection of the finish wall and the top part of the first part of bottle thread where full depth contour exists.

Screen printing) - a printing technique involving the passage of printing medium, such as ink, through a web or fabric, which has been stretched on a frame, to which a refined form of stencil has been applied. The stencil openings determine the form and dimensions of the imprint thus produced.

Sealing bead - a bead of material that is molded onto the top of the land area completely around the top of the neck finish in order to further enhance the sealing capabilities of the component.

Sealing surface - the lip portion of the finish that makes contact with the sealing gasket or liner to form a seal.

Seat - indentations on the base of a bottle that help align bottles on filling and decorating lines so that the bottles are oriented correctly during these processes.

Shelf life - the period of time during which a product can be stored under specified temperature and humidity conditions and remain suitable for use. Shelf life is sometimes called storage life.

Shoulder - the sloped area of a bottle or jar between the neck area and the body of the bottle.

Shrinkage - the change in dimension (decrease) a molded article undergoes after being molded. Shrinkage is caused by cooling and subsequent contraction of the plastic material.

Sifter top - perforated top on a container or fitment designed to dispense contents.

Spray coating - a saran or pvc film, applied to pet, that dramatically improves gas barrier properties and allows for lightweight of containers.

Surface treating - any method of treating a plastic so as to alter the surface and render it receptive to inks, lacquers and adhesives, such as chemical, flame or electronic treating.

"T" dimension - the outside diameter of the thread helix on a bottle finish.

Thermoplastic - (a) capable of being repeatedly softened by heat and hardened by cooling. (b.) A material that will repeatedly soften when heated and harden when cooled. Typical of the thermoplastics family are the styrene polymers and copolymers, acrylics, cellulosics, polyethylenes, vinyls, nylons, and the various fluorocarbon materials.

Threads - on continuous thread styles, the "spiral" of plastic onto which a c/t closure is twisted. Different c/t closure styles feature different numbers of threads.

Torque - twisting force used to either attach or remove the closure.

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.

U.V. Inhibitor - a chemical added to a plastic resin, which absorbs uv light and helps prevent damage to and prolongs the life of the plastic. Tinuvin compounds (hindered amine light stabilizers from ciba-geigy) are an example. (see uv stabilizer).

U.V. Stabilizer (ultraviolet) - any chemical compound which, when admixed with a thermoplastic resin, selectively absorbs uv rays and minimizes chemical and/or physical changes that may be caused. (see uv inhibitor).

Unit cavity - a mold with only one cavity, usually a pilot for the production set of molds.

Volume - referred to as "displacement" and also as "capacity." (1) the amount of water displaced by a model of a bottle. Volume is used to estimate its capacity. (2) the amount of product a bottle is designed to hold, i.e., up to the fill point of the bottle. (3) the overflow capacity, i.e. The amount of product a bottle will hold when filled to overflowing.

Wall - the thickness of the bottle, usually measured along the side walls. B&C Plastics Ltd. manufactures some heavy-wall styles of bottles that offer improved strength and stacking.

Weld lines - a visible line created on the surface of a molded part caused by two flowing streams of plastic joining with the cavity as the cavity is filled.

Wide mouth - containers with large finish opening or those that have a large finish size in relation to capacity.

Yield point - that point beyond which the stresses applied to a material will cause permanent deformation.