Product Catalogue

we offer excellent sale-after service support

With High Quality Guarantee

Search Rank

plastic caps, plastic lids, plastic closures

ISO 9001:2000 Certifications

Plastic Packaging Glossary(J-Z)

Jetting -A turbulent flow in the resin melt caused by an undersized gate or where a thin section becomes thicker.

A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z - Top

Kirksite -Zinc alloy for the construction of blow molds; it imparts a high degree of heat conductivity to the molds.

A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z - Top

Land -The lip of the container to which the closure liner or land seal linerless feature compresses or conforms to tolerance.

Liner -A disk of paper, cork, foam, plastic, etc., retained in a closure to provide a flexible barrier between the closure and the sealing surface of the container.

Liner Well -The space in the closure provided for a liner when required.

Linerless Closure -A thermoplastic closure incorporating a moldsed-in sealing feature, which, when applied to a container with the appropriate finish, seals most liquids within the container.

"L" Dimension-Measured from the top of the finish to the point where diameter "E" extended parallel to centerline intersects the bead (for example, SP-410 and SP-415 finishes).

"L" Style Thread-A type of thread contour (cross section) roughly trapezoidal in outline. The outermost part is radiused. This is a "general purpose" thread contour designed for use with either metal or plastic closures.

lids Ratio (Length to Diameter Ratio) -A term frequently used to define an extrusion screw which denotes the ratio of the screw length to the screw diameter.

LDPE- Low Density Polyethylene.

Label Panel - That portion of the body of a bottle to which labels are affixed or decoration imprinted. Land-See "Sealing Surface."

Lead- See "Pitch."

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.

Light Stability -(1) A measure of the ability of a pigment, dye, or other colorant to retain its original color and physical properties either alone or when incorporated into plastics, paints, inks and other colored films or surfaces, upon exposure to sun or other light. (2) Ability of a plastic to withstand the deteriorating effect of exposure to sun or other light dependently or of the stability of any pigmentation it contains.

Linear Molecule -A long chain molecule of two dimensional structure which may contain side chains or branches. In effect, structural units connected to one another in a linear sequence.

Liner-A disc of paper, cork, composition, etc., retained in a closure to provide a sealing surface against the finish of a container.

Up -The extreme outer edge of the top of a bottle intended to facilitate pouring.

Lubricants- Prevent materials sticking or improve processibility.

Lug- (1) A type of thread configuration, usually thread segments disposed equidistantly around a bottle neck (finish). The matching closure has matching portions that engage each of the thread segments. (2) A small indentation or raised portion on the surface of a bottle, provided as a means of indexing the bottle for operations such as mulU-oass decoration or labeling.

A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z - Top

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

Mechanical Breakaway Bands -Closure that has a portion or section of the skirt perforated or weakened in some manner so that when the closure is opened, this section is designed to break apart and either remain on the container or attached to the closure to indicate the package has been opened.

Metallic Pigment- Particles or flakes of non-oxidized metals or alloys used as pigments to imitate a metallic appearance when added to a clear ink carrier and printed on a container or label. The most commonly used metals are aluminum, bronze, copper, and zinc.

Metallizing -Applying a thin coating of metal to a non-metallic surface. May be done by chemical deposition or by exposing the surface to a vaporized metal in a vacuum chamber.

Modified Buttress Thread -Commonly referred to as "M' style. Developed, with a 10-degree pressure angle, to offer more closure-to-bottle thread contact.

molds -The combination of molds frame and tooling components needed to form sure.

molds Frame -The plates and components required to direct plastic to the tools that form a closure and remove them from the molds.

Multiple Lead Finish -A closure finish that has two or more separate threads within the same space used for a single lead thread. This finish increases the thread pitch and angle and reduces the number of turns to apply the closure.

"M" Style Thread - A type of buttress thread contour (cross section) for use with plastic closures. The profile of the thread is roughly a right triangle. One of the two legs that form the right angle is part of the vertical wall of the neck (finish); the other is the horizontal bearing surface, against which the closure threads engage.

Mandrel- (1) In blow molding, part of the tooling that forms the inside of the parison. (2) In extrusion, the solids, cylindrical part of the die that forms tubing or pipe.

Manifold- A term used mainly with reference to blow molding and injection-molding equipment. It refers to the distribution or piping system which takes the single channel flow output of the extruder or injection cylinder and divides it to feed several blow molding heads or injection nozzles.

Mar Resistance -Ability to retain a satisfactory surface appearance when subjected to rubbing, scuffing, scratching, etc.

Material Distribution -A term which describes the variation in thickness of various parts of the 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.

Melt Flow- The amount, in grams, of a thermoplastic resin which can be forced through a 0.0825inch orifice when subjected to 2, 160 grams force for ten (10) minutes at 230, per ASTM D1238.

Melt Fracture -An instability in the melt flow through a die, starting at the entry to the die. It leads to surface irregularities on the finished article like a regular helix or irregularly-spaced ripples.

Melt Home- The amount, in grams, of thermoplastic material which can be forced through 0.0825-inch orifice when subjected to 2,160 grams force for ten (10) minutes at 190, per ASTM D1238.

Melt Strength -The strength of the plastic while in the molten state.

Melting Point- The temperature at which a solids substance begins to melt under standard conditions.

Meniscus -The free surface of a liquid in a bottle; for example, water in contact with air confined in a capillary tube. The meniscus may be convex (e.g. mercury vs. air in glass), or concave (e.g. water vs. air in glass).

Metalizing -Applying a thin coating of metal to a non-metallic surface. May be done by chemical deposition or by exposing the surface to vaporized metal in a vacuum chamber .

Metering Screw-An extrusion screw which has a shallow constant depth, and constant pitch section over, usually, the last three (3) to four (4) flights.

Migration of Plasticizer- Loss of a plasticizer from a plastic compound with subsequent absorption by an adjacent medium of lower plasticizer concentration.

Mil - A unit of measurement being .001 inch. Minimum Wall- A term that designates 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 relative humidity.

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

molds Number- The number assigned to each molds or set of molds for identification purposes. The number is usually placed in that part of the bottle molds that forms the base of the bottle.

molds Release -See "Parting Agent."

molds Seam -A line formed at the point of contact of the molds halves. The prominence of the line depends on the accuracy with which the mating molds components are matched. Also see "Parting Line."

molding Cycle -(1) The period of time occupied by the complete sequence of operations on a molding press requisite for the production of one set of bottles. (2) The sequence of steps required to produce a bottle without reference to the time.

molding Pressure- (1) The pressure applied to the ram of an injection machine or press to force the softened plastic to completely fill the molds cavities. (2) For blow molding, see "Blow Pressure."

Monomer-A chemical compound which can react with itself or other monomer(s) to form a polymer.

Mottle -A desired or accidental incomplete mixture of colors or values of the same color, giving a speckled or indistinctly spotted appearance.

Multi-Cavity molds- A molds with two or more molds impressions; i.e., a molds which produces more than one bottle 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.

Multiple Head Machine -A (blow molding) machine in which the plastic melt is divided into separate streams (parisons) each giving ultimately a bottle.

A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z - Top

Neck -Another term for the container finish.

Neck-See "Finish."

Neck Bead- Usually a protruding circle on the neck of the bottle.

Neck Down- See "Sag."

Neck Insert- Part of the molds assembly which forms the neck (finish). Sometimes called "Neck Ring."

Neck Ring-See "Neck Insert", "Finish Insert."

Needle Blow- A specified blow molding technique where the blowing air is injected into the hollow article resins.

Nitrile Resins- Polymers containing high concentrations of nitrile having outstanding barrier properties. Generally the constituents are greater than 60% acrylonitrile along with co-monomers such as acrylates, methacrylates, butadiene and styrene.

Nonpolar- Having no concentrations of electric charge on a molecular scale, thus incapable of significant dielectric loss. Examples among resins are polystyrene and polyethylene.

Non-Rigid Plastic - A plastic which has a stiffness in flexure apparent modulus of elasticity of not over 50,000 psi at 25% when determined according to ASTM test procedure D747.

Nozzle - (1) The hollow cored metal screwed into the extrusion end of an extruder or cylinder that matches the depression in the molds. This nozzle allows transfer of the molten plastic from the extruder or cylinder to the molds runners system and cavities. (2) A hollowed metal nose used in injection blow molding for the transfer of molten plastic from the manifold to the parison cavity.

Nylon -The generic name for polyamides.

A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z - Top

Orifice -An opening in a plug, fitment, or dispensing cap through which the product is dispensed.

Oblong- A particular shape. A bottle which has a rectangular cross-section perpendicular to the major axis.

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

Olefins -A group of unsaturated hydrocarbons of the general formula CNH2n, and named after the corresponding paraffins by the addition of "ene" or "ylene" to the stem. Examples are ethylene and propylene.

Opaque -Descriptive of a material or substance which will not transmit light. Opposite of transparent, i.e. Materials which are neither opaque nor transparent are sometimes described as semi-opaque, but are more properly classified as translucent q.v.

Optical Distortion -Change in appearance of objects viewed through a transparent bottle, having certain defects such as waviness of surface, etc.

Orange Peel-An unintentionally rough bottle surface.

Organic Pigments - Characterized by good brightness and brilliance. They are divided into toners and lakes. Toners, in turn, are divided into soluble organic toners and lake toners. The soluble organic toners are usually free from salt-forming groups. Lake toners are practically pure, water-insoluble heavy metal salts or other dye complexes precipitated upon or admixed with a base filler.

Orientation -The alignment of the crystalline structure in polymetric materials so as to produce a highly aligned molecular structure.

Orifice -The opening in the extruder die formed by the orifice bushing (ring) and mandrel.

Oval-A particular shape. A bottle which has an elliptical cross section perpendicular to the major axis.

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

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

A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z - Top

PAM (Pulp/Aluminum Foil/Mylar) -Generic name for SA66, Esterfoil 50, PA-6, Cosmetic Liner .

PE -Polyethylene

PE Foam or PEFM -Generic name for F217 or Sure Seal 222, made of a 3-ply co-extrusion: solids LDPE -LDPE Foam - solids LDPE.

PS -Polystyrene

PP -Polypropylene

PR -Plain Round. Surface finish of closure, which is usually glossy.

Pearlescent Pigments -A class of pigments consisting of particles that are essentially transparent crystals of a high refractive index. The optical effect is one on partial reflection from the two sides of each flake. When reflections from parallel plates reinforce each other, the result is a silvery luster, iridescent effects' and metallic sheen resembling natural or pearl. Effects possible range from brilliant highlighting to moderate enhancement of the normal surface gloss.

Pellet Scar -The characteristic mark caused by the pellet forming a skin when first making contact with the cavity during the molding operation, i.e. Compression molding,

Phenolic -Type of thermoset plastic.

Pitch -The number of turns a thread would circle the neck if the neck were extended one inch. This is commonly referred to as threads per inch. (T.P.I)

Plastic -(Noun) One of many high-polymeric substances, including both natural and synthetic products, but excluding rubbers. At some stage in its manufacture, every plastic is capable of lowing under heat and pressure. (Adjective) Made of plastic capable of flow under pressure or tensile stress.

Plastic Additives -Used to enhance the product, processing, performance, appearance and l or economics of the basic plastic formation.

Platten -The part of the machine that holds the injection molds or compression tools.

Plug - A closure that is pressed into a contained opening, which restricts product flow, by design, often referred to as an orifice reducer.

Polyethylene -A polyolefin composed of polymers of ethylene. It is usually a translucent, tough, waxy solids, which is unaffected by water and by a large range of chemicals. There are three general classifications: low-density, medium-density, and high-density.

Polymer -A high molecular weight organic compound, natural or synthetic, whose structure can be represented by repeated small units. If a single monomer is involved, a homopolymer is obtained. If two or more monomers are involved, a copolymer is obtained.

Polypropylene -A tough, light-weight polyolefin plastic made by the polymerization of high-purity propylene gas in the presence of an organometallic catalyst at relatively low pressures and temperatures. Type of crystalline thermoplastic polymer.

Polystyrene -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. Type of amorphous thermoplastic polymer.

Pop Value -The force measured in pounds to separate the tamper evident band from the body of the closure.

Pressure Angle -Part of the thread that comes in contact with corresponding bottle thread.

" P" Style Thread -A type of buttress thread contour (cross section) for use with plastic closures. The profile of the thread is roughly a right triangle. One of the two legs that form the right angle is part of the vertical wall of the neck (finish); the other is the horizontal bearing surface, against which the threads engage.

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

Parison -The plastic tube formed from which a bottle is formed.

Parison Curl- A condition in which the parison curls upward and outward, sticking to the outer surface of the die ring. Balance of temperatures or orifice between die and mandrel will normally relieve this problem.

Parison Swell-In blow molding, the ratio of the cross sectional area of the parison to the cross sectional area of the die opening.

Parting Agent- A lubricant, often wax, used to coat a molds cavity to prevent the moldsed piece from sticking to it, and thus to facilitate its removal from the molds. Also called "Release Agent."

Parting Line -Mark on a bottle where halves of molds met in closing.

P.B.I. (Plastic Bottle Institute) -A division of the Society of the Plastics Industry, Inc.

PBT (Polybutylene Terephthalate) -A particular thermoplastic polyester.

PC- Polycarbonate.

Pearlescent Pigments -A class of pigments consisting of particles that are essentially transparent crystals of a high refractive index. The optical effect is one of partial reflection from the two sides of each flake. When reflections from parallel plates reinforce each other, the result is a silvery luster. Effects possible range from brilliant highlighting to moderate enhancement of the normal surface gloss.

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

PET (Polyethylene Terephthalate) - Known as thermoplastic polyester. Has the unusual ability 10 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.

Phenoxy Resins -A high molecular weight thermoplastic polyester resin based on bisphenol-A and epichorohydrin.

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

Pinch-Off Blades -The part of the molds which compresses the parison to effect a pinch-off.

Pinch-Off Tail- The bottom of the parison that is pinched off when the molds closes.

Pinhole -A very small hole in a plastic bottle.

Pitch- (1) The distance from any point on the flight of an extruder screw to the corresponding point on an adjacent flight, measured parallel to the axis of the screw. (2) The distance from any point on a full depth thread contour to the corresponding point on an adjacent thread, measured parallel to the axis of the finish.

Plastic -(noun) One of many high-polymeric substances, including both natural and synthetic products, but excluding the rubbers. At some stage in its manufacture, every plastic is capable of flowing under heat and pressure. (adjective) Made of plastic; capable of flow under pressure or tensile stress.

Plastic Deformation -A change in dimensions of an object under load that is not recoversed when the load is removed; opposed to elastic deformation.

Plastic Flow - Change in dimensions and shape of a material when subjected to external weight or pressure, generally at room or cool temperature. Also known as "Cold Flow." See "Creep."

Plastic Memory -The tendency of plastics to return to the original moldsed form. Different plastics possess varying degrees of this characteristic.

Plasticity -The quality of being able to be shaped by plastic flow.

Plasticize -To soften a material and make it plastic or moldsable, either by means of a plasticizer or the application of heat.

Plasticizer Migration- Undesired movement of the plasticizer to the surface of a plastic or from one plastic to another.

Platen -The plates on which the molds assembly is mounted.

Plug-See "Fitment."

Pock Marks-Irregular indentations.

Polar- Union of atoms in which the chemical bond is electrostatic attraction between oppositely charged particles.

Polyallomers -Crystalline polymers produced from two or more olefin monomers.

Polybutylene - A particular polyolefin.

Polycarbonate Resins- Polymers derived from the direct reaction between aromatic and aliphatic dihydroxy compounds with phosgene or by the ester exchange reaction with appropriate phosgene derived precursors.

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

Polymer- A high-molecular-weight organic compound, natural or synthetic, whose structure can be represented by repeated small units; e.g., polyethylene, rubber, cellulose. If a single monomer is involved, a homo-polymer is obtained. If two or more monomers are involved, a copolymer is obtained. Some polymers are elastomers, some plastics.

Polymerization -A chemical reaction in which the molecules of a monomer are linked together to form large molecules whose molecular weight is a multiple of that of the original substance. When two or more monomers are involved, the process is called copolymerization or heteropolymerization. Also see "Polymer."

Polysulfone -A polymer containing the sulfone linkage. These thermoplastic materials exhibit exceptionally high temperature resistance and low creep properties.

Polyolefin -A polymer prepared by the polymerization of an olefin(s) as the sole monomer(s).

Polypropylene - A tough, light-weight polyolefin 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 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.

Polyvinyl Acetate -A thermoplastic material composed of copolymers of vinyl chloride and vinyl acetate; a colorless solids with good resistance to water and concentrated acids and alkalies.

Porosity -(molds) An abnormality of the molds surface. (Bottle) The quality or state of being permeable.

Post molds Labeling (P.M.L.)-Any method of labeling which occurs after the bottle is blown.

Pour-Out Finish -A bottle finish having uniform undercut lips as a sealing surface. Designed to facilitate pouring without dripping.

Preform -An injection-moldsed parison which is blow moldsed by a second step into a plastic bottle.

PP- Polypropylene.

Pressure Angle -The contact face of the bottle and closure thread form.

Pressure Sensitive Label- A die cut label that is applied from a web, on which it is carried, to the bottle by gentle pressure.

Programming -A process for changing the size, weight or wall thickness of the parison mechanically during its formation.

Prototype molds- A simplified molds often made from a light metal casting alloy or epoxy resin in order to obtain preliminary bottles.

PS- Polystyrene.

Purging -The forcing out of one color or one type resin 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 bottle designed to allow an even bearing surface on the outside edge and prevent the bottle from rocking.

PVC (Polyvinyf Chloride) -A thermoplastic material composed of vinyl chloride; a colorless solids with outstanding resistance to water, alcohols, and concentrated acids and alkalies. Classified as: Plasticized and Unplasticized.

A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z - Top

Removal Torque -The torque force, measured in inch-pounds, required to unscrew a closure from a container.

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

runners -Channel that connects the sprue and gate.

runnersless molds -molds that are designed so that the runners is heated and stays molten. runners is not ejected after each shot.

Reaming -A post-operation used to size the inside of a bottle finish.

Recessed Panel- A bottle design in which the area for labeling is indented or recessed. Also see "Label Panel."

Reciprocating Screw -An extruder in which the screw when rotating is pushed backwards by the molten polymer which collects in front of the screw. When sufficient material has been collected, the screw moves forward and forces the material through the head and die at a high speed.

Recycle (Regrind) -Ground material from flash and trimmings which is fed back into the molding machine.

Recycled Plastic -A plastic prepared from used articles which have been cleared and reground.

Regrind- A thermoplastic from a processoræŠ¯ own production that has been cleaned and reground.

Relief Angle -The angle of the cut away portion of the pinch-off blade measured from a line parallel to the pinch-off land.

Resin -Any of a class of solids or semi-solids organic products of natural or synthetic origin, generally of high molecular weight, with no definite melting point. Most resins are Polymers.

Rib -A reinforcing member of a fabricated or moldsed part.

Rigid Plastics- For purpose of general classification, a plastic that has a modulus of elasticity either in flexure or in tension greater than 100,000 psi at 23% and 50% relative humidity when tested in accordance with ASTM Method D747 or D790 Test for Stiffness of Plastics.

Rigid PVC- Polyvinyl chloride or a polyvinyl chloride/acetate copolymer, characterized by a relatively high degree of hardness; it may be formulated with or without a small percentage of plasticizer.

Rigid Resin -One having a modulus high enough to be of practical importance; e.g., 500,000 psi or greater.

Rocker- A plastic bottle with a bulged or deformed bottom, causing rocking of the bottle when in the upright position.

A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z - Top

"S" Dimension - The vertical distance from the top of the finish (land area) to the intersection of the finish wall and the first part of the thread where full depth exists.

S.P.I. - Society of the Plastics Industry

Screw and Barrel - The part of the injection unit that melts and mixes material.

Score Line - Area that the closure is cut or scored through the band and into the leaders.

Seal Area - Area in which the closure, when lining material is added, seals off on the bottle.

Seal Lip - The lip is located at the bottom of the seal area. Lining material should not extend beyond this lip area.

Sealing Surface - The surface of the finish of the container on which the closure forms the seal.

Sink Mark - A depression on the surface of a plastic container or closure generally caused by non-uniform shrinking of plastic.

Short - An area in a plastic part that is not completely formed.

Shot Size - The amount of plastic that must be processed and injected in the molds before one cycle

Snap Fit Closure - A closure that is held in place through the use of beads or undercuts rather then threads.

SM -SSmooth Top of a closure

Sprue - The section of runners between the runners channel and gate.

ST - Stippled Top of a closure

Stack molds - A molds with 2 parting liner that can double output without doubling machine tonnage.

Stippling - A decoration consisting of a system of closely spaced small dots raised on the outer surface of bottles.

Storage Life - The period of time during which an item can be stored under specified temperature conditions and remain suitable for use. Storage life is sometimes called "shelf life".

Stripper molds - Strips the closure thread off of the core (bump off). Does not unscrew from molds.

Stress Crack - External or internal crack in plastic caused by tensile stresses less than that of its short-time mechanical strength. The environment to which the plastic is exposed frequently accelerates the development of such cracks. The stresses that cause cracking may be present internally or externally or may be combinations of these stresses. The appearance of a network of fine cracks is crazing. Also see "environmental stress cracking" and "thermal stress cracking"

Stripped Thread - A CT closure thread that is designed to eject from a closure molds without the use of unscrewing. Its thread profile is typically "L" style.

Stripper Bushing - The tooling component that forms the surface on the bottom open end of the closure between the inside formed by the core and the outside formed by the cavity.

Stripping Torque - The amount of application torque that causes the threads of the closure to override the container threads.

Surface Finish - The degree of gloss, matte, or type of ribbing.

" S" Dimension - Locates the position of the bottle thread with respect to the top of the finish. It is a vertical distance from the top of the finish to the intersection of the finish wall and the top of the first part of the thread where full depth contour exists.

"S1" Dimension - Locates the position of the bottle thread with respect to the top of the finish. It is a vertical distance from the top of the finish to intersection of the finish wall ("E" Diameter) bottom of the thread form where full depth contour exists. This dimension influences the amount or thread engagement and closure orientation.

Sag - The local extension of the parison (often near the die face) due to gravitational forces during extrusion. This causes necking-down of the parison.

SAN (Styrene Acrylonitrile) - Thermoplastic copolymer with good stiffness, scratch, chemical and stress-crack resistance.

Scar - The characteristic mark caused by the pinch-off operation.

Screen Pack - A screen or layers of screens supported by a breaker plate, usually located between the extruder and the die head.

Scuff - See "Abrasion".

Sealing Surlace - The surface of the finish of the container on which the closure forms the seal.

Seam - See "molds Seam."

Section - An identifiable part of a bottle.

Semi-rigid Plastic- For purposes of general classification, a plastic that has a modulus of elasticity either in flexure or in tension of between 10,000 and 100,000 psi at 23% and 50% relative humidity when tested in accordance with ASTM Method D747 and D790 Test for Stiffness of Plastics.

Set - (1) The final form a material assumes in the transition from its plastic (fluid) state to a condition of desired solidsity. (2) (verb) Generally, to reach a state of set; to harden.

Shark Skin - A surface irregularity of a container in the form of finely-spaced sharp ridges caused by relaxation effect of the melt at the die exit. Also see "Melt Fracture", "Orange Peel."

Shear - An action resulting from applied forces which causes or tends to cause two contiguous parts of a body to slides relatively to each other in a direction parallel to their place of contact.

Shear Strength - (1) The ability of a material to withstand shear stress. (2) The stress at which a material fails in shear.

Shelf Life - The length of time that a bottle, will remain in a saleable or acceptable condition under specified conditions of storage. Also known as Storage Life.".

Shot - The yield from one complete molding cycle, including scrap.

Shot Capacity - The maximum weight of material which an accumulator can push out with one forward stroke of the ram.

Shoulder - That part of a bottle between the main body and the neck (finish).

Shrink Mark - An imperfection, a depression in the surface of a moldsed bottle where it has retracted from the molds.

Shrinkage - The decrease in dimension which a bottle undergoes after being moldsed. Generally caused by cooling and subsequent contraction of the plastic material. Also see "molding Shrinkage."

Silk Screen Printing (Screen Process Decorating) - This printing method, in its basic form, involves laying a pattern of an insoluble material in outline on a finely woven fabric, so that when ink is drawn across the screen, it is able to pass through the screen in the desired areas only.

Sink Mark - See "Shrink Mark."

Skirt - The vertical wall of a closure cap below the shoulder.

Sleeve Label - A decorated, plastic sleeve that fits over and on plastic bottles.

Specific Gravity -The density (mass per unit volume) of any material divided by that of water at a standard temperature, usually 4ç™ˆ. Since wateræŠ¯ density is nearly 1.00 g/cc, density in g/cc and specific gravity are numerically nearly equal.

Spider - (1) In a molding press, that part of an injection mechanism which operates the ejector pins. (2) In extrusion, a term used to denote the membranes supporting a mandrel within the head/die assembly.

Spider Lines - Vertical marks on the parison or bottle caused by the spider.

Spin Welding - A process of fusing two objects by forcing them together while one of the pair is spinning, until frictional heat melts the interface.

Stabilizer - An ingredient used in the formulation of plastics to assist in maintaining the physical and chemical properties of the compound materials at their initial values throughout the processing and service life of the materials.

Static Electricity - Charges of electricitv which sometimes develop in bottles during handling or in machine operation. May cause undesired dust attraction, sparking, etc.

Stiffness - Rigidity; resistance to bending.

Stippling - A decoration consisting of a system of closely spaced small dots raised on the outer surface of bottles.

Storage Life - The period of time during which an item can be stored under specified temperature conditions and remain suitable for use. Storage Life is sometimes called "Shelf Life."

Stress Crack - External or internal crack in plastic caused by tensile stresses less than that of its short time mechanical strength. The development of such cracks is 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 these stresses. The appearance of a network of fine cracks in crazing. Also see "Environmental Stress Cracking" and "Thermal Stress Cracking."

Striation - A longitudinal line in the parison or bottle due to a disturbance in the melt path.

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

Surfactant - A wetting agent.

Surging - Unstable pressure build-up in an extruder leading to variable throughput and waviness of the parison.

Sweating - Exudation of small drops of liquid, usually a plasticizer or softener, on the surface of a plastic part.

Swelling Resistance - Ability of a plastic to resist increase in size due to contact with chemical agents.

A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z - Top

"T" Dimension - The larger diameter of the inside of the closure measured "wall to wall". Corresponds to the "T" dimension (thread) of the container.

T .P .I. - Threads per Inch, see pitch.

Tamper Band - The tamper-evident feature of the closure. Usually connected to the closure skirt by leaders or bridges.

Tamper Evident Breakaway Band Closure -Designed to reveal that removal of the closure has been attempted. The section of the closure skirt that is weakened or perforated in some manner that when the closure is opened that section is designed to either remain on the container or stay partially attached to the closure.

Tamper Evident Closure -A closure or liner system that incorporates a feature that visually indicates that the closure has been removed or the product has been exposed. Removal of the closure or liner system activates the indicating feature.

Tamper Evident Tear Band -Designed to reveal that removal of the closure had been attempted. This closure has a band, normally with a tab for grasping, designed to be detached by the consumer.

Tamper Proof - In theory, a package that cannot be tampered with.

Thermoplastic - (Adjective) Capable of being repeatedly softened by heat and hardened by cooling. (Noun) A material that will repeatedly soften when heated and harden when cooled. Most polymers user I

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

Tail Scar - See "Scar."

Tamper Evident Closure - A closure that incorporates a feature (such as a separable band) that visually indicates that the closure has been removed. Removal of the closure activates the indicating feature.

Tensile Strength - The resistance of a material to longitudinal tension stress.

Thermal Conductivity - Ability of a material to conduct heat.

Thermal Degradation - Deterioration by heat.

Thermal Stress Cracking (TSC) - Crazing and cracking of some thermoplastic polymers which results from over-exposure to elevated temperatures.

Thermoplastic - (adjective) Capable of being repeatedly softened by heat and hardened by cooling. (noun) A material that will repeatedly soften when heated and harden when cooled. Most polymers used for bottles are thermoplastics.

Thermoset - 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 thermosetting family are the epoxies, glyptals, melamines, ureaformaldehyde resins and phenolics.

Thread Engagement - The actual contact made by the closure and bottle finish thread. Usually specified in number of turns.

Tolerance - Permissible maximum deviation from specified dimensions or quantities or specifications.

Toner - Any of several dyes used to add a particular color characteristic (e.g., blueness, whiteness, etc.) to either a clear or pigmented plastic.

Top Blow - A specific type of blow molding process which forms bottles by injecting the blow air into the parison at the top of the molds.

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 permanent distortion.

Torpedo - A streamlined metal block placed in the path of flow of the plastic materials, thus forcing it into intimate contact with heating areas. Also called "Spreader ."

Torque - The amount of rotational force applied to a closure to seal (on-torque) or open (off-torque) the bottle. Usually expressed in terms of "inch pounds" and measured by means of a reliable torque meter.

Torque Tester - A type of torque meter used for measuring removal torque of screw caps. Can also be used to apply screw caps to a known predetermined tightness.

Torsion - Stress caused by twisting a material.

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

Transparent - Descriptive of a material or substance capable of a high degree of light transmission; i.e., clear enough to see through.

A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z - Top

Ultimate Strength - Term used to describe the maximum unit stress a material will withstand subjected to an applied load in compression,tension or shear test.

Ultrasonic Welding - A welding method accomplished through the application of vibratory mechanical pressure at ultrasonic frequencies (20-40 Hz).

UPC (Universal Product Code) - A 10-digit, all numeric code which uniquely identifies 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.

UV 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 by UV.

Undercut - An indentation or protuberance on a bottle that in some cases impedes the withdrawal from the molds.

Unit molds - A molds which comprises only a single cavity , frequently a pilot for the production set of molds.

A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z - Top

Virgin Material - A plastic material that has not been subjected to use or processing other than that required for its initial manufacture.

Viscoelastic - A term that refers to plastics which "store" and dissipate energy during mechanical deformation. The term explains "Flow" of plastic materials under stress.

Viscosity - Internal friction or resistance to flow of a melt. The constant ratio of shearing stress to rate of shear. In melts for which this ratio is a function of stress, the term "apparent viscosity" is defined as this ratio.

Volume - Referred to as "Displacement"; also as "Capacity." (1) The amount of water displaced by a model of a bottle; used to estimate its capacity. (2) The amount of product a bottle is designed to hold; i.e., up to the fillpoint of the bottle. (3) Also, the overflow capacity; i.e., amount of product a bottle will hold when filled to overflowing.

Vent - In a molds, a shallow channel or minute hole cut in the cavity to allow air to escape.

Vertical Load - See "Top Load."

Vinyl - Informal generic term for any of the vinyl resins.

A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z - Top

"W" Dimension - The width (vertical height) of the bead on certain bottle finishes.

Waist - The portion of a bottle which has a smaller cross section than the adjacent areas.

Warpage - Dimensional distortion in a bottle after molding.

Weld Lines (Also "Weld Marks" or "Flow Lines") - A mark on a moldsed plastic bottle through a sharpened hollow needle which pierces the parison.

Wetting Agent - Chemical agent used to overcome reluctance of dissimilar materials, one of which is a liquid, to wet or mix, by reduction of the surface tension of the liquid.

A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z - Top

Yield Point - That point beyond which the stress in a material will cause a permanent deformation.

Yield Value (Yield Strength) - The lowest stress at which a material undergoes plastic deformation. Below this stress, the material is elastic; above it, viscous.