Glossary

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

Adaptor
In an extruder, the connector through which the resin flows from the extruder to the die.

Additive
Substances added to resins to alter basic properties.

Adhesion
The state of sticking together two or more materials.

Air Gap
In an extruder, the distance between the die and the nip.

Aluminum Foil Laminations
A combination of aluminum foil with a paper backing used as a barrier and often combined by means of an adhesive or extruded polyethylene.

Angle of Slide
The angle at which solid materials will begin to slide or flow from the horizontal.

Anti-Blocking Agent
Agents that add friction and prevent plastic from sticking together.

Antioxidant
An additive that stabilizes plastics so they are not broken down by oxygen; especially useful with rubbers, polypropylene, and ABS.

Antistatic Agent
Adds electrical conductivity and avoids electrostatic buildup.

Apparent Density
Weight per unit volume, including voids in the product.

Appearance
Visual inspection of the product you are making, looking for defects in the surface.

ASTM
American Society for Testing and Materials

ASTM International is composed of more than 132 technical standards writing committees. Together, they have published more than 9,100 standard specifications, tests, practices, guides, and definitions for materials, products, systems, and services.

ASTM International has published standards dealing with metals, flammability, chemical products, lubricants, fossil fuels, textiles, paint, plastics, rubber, pipe, forensic sciences, electronics, energy, medical devices and countless other topics.

Back Seam Woven Bag
A woven bag that contains a seam on its backside.

Baggy Paper
A baggy sheet that when pulled tight has one or more slack areas. These slack areas can be located in the middle of the sheet or at its edge.

Balance
Scale or other instrument used to weigh samples.

Barrel
Cylinder that houses the screw of the extruder.

Base Roll
Uncoated or plain paper in roll form, before converting.

Base Paper
Rolls of uncoated paper.

Basis Weight
The weight of a ream (500 sheets) of paper that is the standard basic sheet size for that grade (also referred to as substance weight). At CEI, basis weight is measured as the weight in pounds of 3000 square feet of paper. The purpose of basis weight is to distinguish the different thicknesses of paper. In other words, a paper with a 24# basis weight is thicker than a paper with a basis weight of 20#.

Biaxial Orientation
Molecules are reoriented from random to a more parallel structure in two directions. Orientation improves strength, heat shrinkability, and other physical properties.

Biaxially Oriented polypropylene (BOPP)
A polypropylene film that has been stretched in both the machine and cross directions.

Biodegradable
The ability to break down through the action of a naturally occurring microorganism over a period of time

Black Light
Ultra-Violet light used to detect the presence of primer (with UV agent added) on a sheet of paper under a clear poly surface.

Blisters
Localized raised portions of the surface (like bubbles) in which there is a separation between the top and bottom of the coated sheet.

Blocking
When the layers of a roll are stuck together so that the roll does not unwind easily, causing surface damage when split apart.

Bond
The adhering together of two or more materials.

Breaks
A term used to denote a tear in a roll of paper which occurs while the paper machine is running. Such breaks are generally spliced and marked by a protruding flag.

Bridging
Bond of poly to paper of less than desired level in which the poly stretches across the tear line when a web is torn slowly.
Brightness
The degree to which paper reflects light of a specified wavelength. Brightness can vary from 0% (black) to 100% (blue-white). It is measured with a Technidyne Brightness Meter.

Broke
Paper trimmings or damaged paper from the machine or finishing rooms, usually returned to beaters for re-processing into saleable paper.

Burst Strength
Resistance of paper to rupture under pressure, as indicated in pounds per square inch on a Mullen or "pop" tester.

Butt Rolls
Partial end section of a roll that can be used again.

C1S
A clay coated surface.

Calender
A series of rollers; the film or sheet is passed between a pair of rollers, the final pair determining the thickness of the material.

Calender Blackening
A term descriptive of darkening of the intended shade of paper by excessive calendering or by calendering wet paper.

Caliper
The thickness of paper expressed in thousands of an inch.

Carbon Footprint
A measure of the impact had on the environment in terms of the amount of greenhouse gases produced.

CD
Cross direction.

Center
Middle position on web, halfway between the front (operator's side) and back of machine.

Chip Board
An inexpensive, thick one-ply cardboard, typically made from recycled paper stock.

Chill Roll
Water cooled metal roll that is used to cast the hot poly against paper to form the surface quality of the sheet; also used with a rubber roll to form a nip to physically bring paper and poly together for bond.

Clean Strip®
Easy open tear strip feature of film reap wrap produced by Coating Excellence International.

Coating Absent
The entire width of the web is not coated. The length of the uncoated area can vary from several feet to an entire roll.

Coating Voids/Skips
Refers to small areas of the sheet without coating. They are usually elongated in the machine direction and vary in length and width, from a fraction of an inch to several inches or more.

Cockles
A rippling effect given to the surface of a sheet of paper which has not been properly dried, sometimes caused by moisture pick-up.

Coefficient of Friction
A number which represents the friction between two surfaces. Between two equal surfaces, the coefficient of friction will be the same. The symbol usually used for the coefficient of friction is x, where 0 < x < 1. The measure of resistance to motion of two surfaces when dragged either on itself or against a given surface at a given weight and speed.

Coextrusion
Two or more resins are extruded and combined at the die.

Cold seal
Sealing a packaging product by the use of pressure as compared to heat.

Color Match Side
One side of a sheet of paper. MG – lighter, smoother, wire side. MF – Darker, felt side.

Core
The center cardboard tube used that paper is wound onto.

Core Plug
A circular disc that is put in the ends of the core to add stability. Cores may be metal, wood, or plastic.

Corona Discharge
Ionization of air or gas when a high voltage is applied (5000 + volts). The discharge oxidizes the film by forming polar groups on the surface making it more receptive to inks, adhesives, and other coatings.

Corrugated
See "Roped".

Cracked Edges
A crack, tear, or nick at the edge of the sheet.

Cross Direction / Cross - Machine Direction
A line perpendicular to the direction the paper travels through the paper-making machine. Also referred to as cross direction or cross grain.

Cross Web Variation
How even the web or sample is from side to side, can be measured in basis weight or caliper. Used to determine what a roll will look like before it is finished.

Grade
The classification given to paper due to its unique characteristics, which include brightness, opacity, cotton content, etc.

Crushed Core
Any degree of out-of-roundness of the core that prevents a shaft from being inserted into it.

Cure time
The time required for a material to set at a given temperature and humidity

Curl
Undesirable distortion or waviness occurring to the paper due to the presence of excess moisture or humidity. The measure in inches of how much a sample lifts or rolls up away from a flat surface.

Deckle
On the extruder, deckle rulers that prevent the poly from overflowing on the sides of the web. The deckle determines how wide the poly width will be on a particular machine. These may be adjusted manually or electronically depending on machine.

Degradable
The ability to break down through chemical reactions

Delamination
The separation of the components of a laminated material.

Denier
A unit of weight indicating the fineness of fiber filaments and yarns, both silk and synthetic, and equal to a yarn weighing one gram per each 9,000 meters

Density
The weight per unit of volume.

Diagonal Curl(D)
The curl occurs on a line that is diagonal to the side and the end of the web.

Die
The opening through which the plastic is extruded.

Die Cutter
Device used to cut small samples to an exact size to measure basis weight in grams per square inch using a factor.

Die Streak
Defect in a poly coated surface that runs in the machine direction caused by a flaw in or dirt on the die jaws.

Dirt
Visible foreign matter (Bark, pitch, scale, slime, etc.) in the sheet or on the side of the roll. See also "Foreign Material in Sheet".

Dished
See "Telescoped".

Drawdown
Shrinkage of the plastic as it is pulled from the die at a rate faster than it is being extruded from the die. Drawdown ratio is the ratio of the die opening to the thickness of the finished material.

Drop Test
Determining bag strength by dropping filled bags from predetermined heights and positions until failure occurs.

Easy open tear strip
A strip of material, normally plastic, fastened under a bag closing tape, used to pull across the top of a roll/fold/tape bag as an easy open feature.

Edge Protection
A packaging material used to wrap the edges of a roll to help protect them from damage during shipping and roll handling.

Electron
Negatively charged particle(s) of an atom.

End Curl (MD)
Axis of curl is in the cross machine direction causing the machine direction ends of the paper to curl up or down.

Extrude
The output of an extruder.

Extruder
The mechanism that generates a continuous flow of a plastic material; whether a pipe, tube, coating, or film. The types of extruders are many with single or multiple screw and ram types.

Extrusion
The process of melting resin to apply to paper or to bond film or foil to woven material.

Eye Mark
The position of the printed eye mark on a roll of paper. The different Eye mark positions can be found on the "Standard Unwind Roll Chart".

Face Width
The width of the front side of a bag.

Felt Side
The top side of the paper, usually recommended for best printing results. This side of paper is darker, caused by drainage on paper machine. The side of web opposite the wire wide.

Fiber Tear
The amount of paper that stays on the poly when poly is removed by scotch tape during bond testing.

Fill End
The portion of a bag that is left open so that contents can be added into the bag before sealing

Films
A thin plastic used in packaging. It is less than 10 mils (.010") thick compared to the thicker sheets.

Finish
The relative texture of the surface. The condition of surface on both coated and non-coated webs (e,g., matte, gloss, MF, MG).

Finished Goods
Product that is packaged and ready to be shipped out to customers.

Fisheye
Defect in poly surface caused by unmelted resin pellet

Flag
A small piece of paper or board inserted in a roll of paper so that it extends beyond the end to indicate the location of a splice.

Flexible Packaging
Packaging that utilizes materials such as paper, foil, film, etc.

Flexography
A printing style that utilizes flexible printing plates made of rubber or plastic that contain a measured amount of ink. The plates rotate, contacting the print material and transferring ink.

Formula
Mixture of components to make a coating.

Friction
The resistance to lateral motion when one attempts to slide the surface of one object over another surface.

Front
Location on web or machine nearest the operator’s control panel.

Front Center
Location on web or machine between center position and front position.

Gauge
The instrument on the extruder that controls the profile or evenness of the poly coating.

Gel
Also known as fish eyes. An uneven coating on the paper that is shaped like a tear drop. Small gels can be microscopic. Large gels can be several inches long.

Ghosting
When ink transfers from front of web to back, leaving a faint image of the design where you didn’t want it.

Gloss
The shiny, reflective appearance of the coated paper, when placed under a light source. Measured with a Hunter Gloss Meter. Gloss can vary from 0% (Matte finish) to 100% (Mirror-like finish).

Grain Direction
The direction taken by a majority of the fibers in any sheet of paper. Synonymous with "machine direction", the opposite of "cross direction".

Gusset
The side portion of a bag which allows for volume.

HDPE
HDPE (high density polyethylene) is the high density version of PE plastic. It is harder, stronger and a little heavier than LDPE, but less ductile. Dishwasher safe.

HDPE is lighter than water, and can be molded, machined, and joined together using welding (difficult to glue).

The appearance is wax-like, lusterless and opaque. The use of UV-stabilizers (carbon black) improves its weather resistance but turns it black. Some types can be used in contact with food.

Headers
Round or square, typically corrugated sheets that serve as a protective barrier over the ends of the rolls.

Heat Seal

The bonding of two poly surfaces together with heat, pressure, and swell time.

Heat Seal Ability
That the poly-coated paper will heat seal under the conditions of temperature, clamp pressure, and dwell time at which the customer wants to operate.

Heat Transfer
Method of moving wax from one surface to another using heat and pressure and a HIX N600 transfer machine.

Hot Oil Bond
Test run on poly-coated sample to ensure bond for oil can grades.

Humidity
Moisture condition of the air. Relative humidity is the percent of moisture relative to the actual amount which air at any given temperature can retain without precipitation.

ICC
Interstate Commerce Commission. A federal agency for regulating commerce that takes place in more than one state. One of its most familiar activities is regulation of trucking.

ICC Bar
A bar across the rear of the trailer (below the trailer bed) used to lock trailer to dock as required by the Interstate Commerce Commission.

I.D. (Inside Diameter)
The measured distance from inside wall to inside wall through the center of a core.

Impact Strength
The amount of impact a bag can withstand before it tears.

Ink Color
The color of an ink means that the color used is the color specified.

Ink Receptivity
The ability of a surface to absorb ink.

Ink Rub
Test of ink to determining how well it is dried and how it sticks to poly or paper.

Kinetic
Resistance to motion while object is moving or the amount of drag.

Kinetic COF
The force needed to keep an object moving once it is started in motion.

Laminated
Paper that is developed by fusing one or more layers of paper together to the desired thickness and quality. Often other substances like thin sheets of metal, plastic, etc. are fused to paper.

Lamination
Combining multiple layers of material into a single structure.

L/D Ratio
The ratio of an extruder's screw length to its diameter.

LDPE
Low Density Poly-Ethylene (Plastic)
LDPE is used for packaging items such as foils, trays and plastic bags for both food and non-food purposes. Used as protective coating on paper, textiles and other plastics, for instance in milk cartons.

Lint
Small fuzzy particles in paper.

Machine Direction
Establishes the grain direction, which is always parallel with the travel of the paper over the wire. Direction of paper parallel to its forward movement when being made on paper machine (MD).

Machine Direction Curl
Also known as the end of the sheet (as you face in machine direction).

Master Roll
A roll of paper after going through a converting operation but before rewinding.

Matte Finish
A coated paper finish that is flat, not shiny like a gloss, but still keeps much of the ink from being absorbed by the paper and produces an excellent image.

MD
Machine direction.

Metallized
A very thin coating of metal deposited on film or foil.

MF(Machine Finish)
Finish of paper when made on a paper machine that does not have a large smooth dryer roll. Paper does not have a smooth shiny side (MF).

MG (Machine Gloss)
A sheet of paper having a smooth shiny surface on one side; caused by a large surface dryer on a Yankee Machine (MG).

Moisture
The amount of water in the sheet, expressed as a percentage of the total weight of the paper. As the roll absorbs moisture, the fibers at the edges and outer layers of the roll expand.

Moisture Barrier
Prevents the movement of moisture from one area to another

Moisture Content
Refers to the amount of moisture found in a sheet of paper. Average amount ranges from 5 to 8 percent. This figure varies from sheet to sheet since paper will emit or absorb moisture according to the condition of the surrounding atmosphere. Moisture loss is realized in the form of shrinkage, which begins at the edges of the paper and moves across the grain causing the sheet to tighten and curl.

Moisture Vapor Transmission Rate
The rate of grams of moisture that will pass through an area of 100 sq in of barrier material in a 24 hour period expressed as gm/100 sq in/24 hr.

Moisture Welts
Bands, raised welts, or soft wrinkles around the roll (in the machine direction). They are not perfectly parallel to the edge, but rather wander like a snake. A moisture welt does not meet itself after going completely around the roll. Since they exist near the outer diameter of a roll, they usually disappear when a small amount of paper has been slabbed from the roll.

MSDS
Material Safety Data Sheets (MSDS), regulated under Workplace Hazardous Materials Information System (WHMIS) legislation, for chemical products. They have been available to workers for many years. A Material Safety Data Sheet is designed to provide both workers and emergency personnel with the proper procedures for handling or working with a particular substance. All companies must have an MSDS sheet on file for all chemicals or hazardous material within the plant.

Mullen
Burst strength on a sheet of paper.

Neck-in
The difference between the width of polymer as it leaves the die and the width when it is coated on a substrate.

O.D. (Outside Diameter)
The measured distance from the outside edge to the outside edge of the profile through the center of a roll.

Offset
When a roll shifts over on itself causing a ridge in the profile of the roll

Offset Edge
The edge of the roll is not a flat surface. As the roll is wound, the edge of the paper shifts from side to side so that some of the layers of the roll are offset from others.

Offset Printing
A method of printing where inks are transferred from a plate to a rubber blanket, and then onto the printing surface.

Opacity
The resistance of paper to the passage of light, measured with an opacity meter. 100% opacity means the paper is totally opaque (no light goes thru), 0% means it is transparent, like clear glass. Sometimes referred to as "show-through", this term refers to the property of a sheet which prevents dark print areas from showing through the paper to the other side.

Odor
Test to determine if a sheet has a smell, and if it is to liking or not.

Opacimeter
The instrument with which the degree of opacity may be measured.

Outturn Sample
A sample from every master roll 12" x full web width saved for future use and marked with: date, machine, roll number, and order number.

Oxygen Transmission Rate
The rate in cubic centimeters that pure oxygen will pass through an area of 100 Sq in of barrier material in 24 hours, expressed as: cc/100sq in/24 hr.

P3K Treatment
Measure of surface tension produced by either electronic or flame treating a surface to make that surface easily wet by liquids.

Packaging Converter
A company that converts packaging materials into finished products.

Palatability
The degree that packaging materials affect the taste of the contents inside.

Picking
The lifting of any portion of a paper surface during the printing impression, due sometimes to inadequate surface sizing and sometimes to ink being excessively tacky.

Pinch bottom bag
A bag formed with adhesive applied to an extended lip on the bag opening along with part of the bag face. That part of the bag can then be heated to re-activate the adhesive after filling, folded over the bag opening and pinched to close the bag.

Pinholes
Small holes, the size of a pin, that go completely through the coating. The measurement is the number of pin holes per square foot. When pinholes are present, the number usually varies from 0 to 3 per square foot.

Pipe Liners
A delamination of foil from the base paper that is about the size of a pencil.

Plastic
Materials consisting of high molecular weight polymer(s) that are fluid at some stage, but solid in their final state.

PO Number
Purchase order number.

Poly
Plastic used to coat on paper to give heat seal, moisture, and holdout properties.

Poly Slug
A chunk of poly that leads from the die that is not flat like a web.

Polyethylene
A thermoplastic material composed solely of polymers of ethylene abbreviated PE.

Polypropylene
Any of various thermoplastic resins that are polymers of propylene. They are hard and tough, and are used to make molded articles, packaging materials and fibers.

Porosity
The degree to which air can pass through the fibers in a sheet, measured (in seconds per unit volume) by the time that is required for a given volume or air to flow through the sheet.

Porosity Test
A test which measures the time required for a given amount of air flow through a sheet of paper. This test is a measure of how closely the fibers are compacted and bonded together. A paper of high porosity is one that is quite dense and relatively non-porous; this test is made with a "Densometer".

Post Gusseting
The operation of forming a longitudinal tuck or gusset into each side of a continuous tube of material. This is typically done in a secondary operation after the material has been formed into a tube. The gussets typically form the sides of a bag which is closed on one end prior to filling.

Primer
Layer of material used to promote better bond between poly and paper.

Primer Coverage
Test to see if you have primer under the poly. Primer has a UV agent to make it fluorescent when examined under ultraviolet light.

Printability
The property of paper which yields printed matter of good quality. This property at present is not accurately defined; it is judged by uniformity of color of the printed areas, contrast between printed and clear areas, legibility of the printed matter and show-through. It is generally believed that this property is related to ink receptivity and its uniformity, compressibility, smoothness, and opacity.

Print Direction
The orientation of the copy relative to the unwind direction of the roll and according to what the customer specified.

Print Skips
Refers to areas of the paper that were not printed.

Print Wrong Copy
The wrong printing plate was used.

Print Void
Area without print; caused by press opening or running out of ink.

Profile
The roll surface from edge to edge.

Proof
A trial print that is taken for examination or correction before mass printing.

Puckers
A rise or dip in the surface of a sheet of paper caused by uneven moisture.

Pyrometer
Instrument used to measure surface temperature.

Raw Materials
Anything that is used to make up finished goods; examples: paper, foil, film, polyethylene.

Ream
3,000 square feet of product area. Reported in pounds or number shipped.

Ream Wrap
The outer wrapper of a package of copy paper; grade of paper used as a moisture barrier for wrapping; 500 sheet stacks of paper.

Recyclable
The ability to be treated or processed to be made suitable for reuse

Register
In printing, register is the placement of two or more images on the same paper in such a manner as to make them in perfect alignment with each other. When a printing job is in exact register, succeeding forms or colors can be printed in the correct position relative to the images already printed on the sheet.

Repeat
The measured length from eye mark to eye mark on material that is printed in register.

Repeat Length
The length of a print on a finished roll.

Repel Treatment
Test used to determine level of fluorochemical in paper. This increases the oil repellency of sheet (TL-30).

Rewinder
Equipment which slits and rewinds paper webs into smaller rolls.

Reworked
Rewinding a set-out to remove the off quality material or to remove a physical defect from the roll.

Roll/fold/glue
An operation done to the top or bottom of a side gusseted bag, in which the bag is folded over twice in the same direction and glued in position to close off the bag.

Roll/fold/tape
An operation done to the top or bottom of a side gusseted bag, in which the bag is folded over twice in the same direction and taped in position to close off the bag.

Roped
Ropes or corrugations are a series of parallel diagonal ripples or wrinkles in the paper running around the roll (in the machine direction). The pattern of uniform diagonal markings, which is usually 1" to 4" wide resembles a rope.

Rubber Roll Mark
A visual image in the surface of the poly caused by something sticking to the rubber roll or a defect in the rubber or in the grinding.

Schmidt-Hammer Test
The hardness of paper rolls is an important quality factor in the working processes of the paper, film, and foil industry. Rolls that are too hard, or too soft, rolls that are unevenly wound, or rolls with different moisture contents can cause difficulties during the printing process. The hardness control of such rolls, in particular their uniformity over the whole width, has to date created many problems.

SCHMIDT-Hammer® Test is based on the principle of rebound measurement and is very simple in its handing. The impact plunger of the instrument is pressed against the paper roll which compresses a spring. After reaching a certain point, the spring is released and an internal hammer mass is launched against the impact plunger. The amount of hammer mass rebound depends on the hardness of the test piece. This rebound amount is then shown on a scale of 10 to 100. Test intervals of 2" to 4" (5 to 10 cm) across the whole width of the roll will give the values for the "Hardness-Profile" within a short period of time. The testing is non-destructive with exception of very light marks that the instrument leaves on the top two or three layers. Such "Hardness-Profiles" will show immediately whether the rolls have the necessary consistency. Rolls that are too soft, or rolls with inconsistent hardness are immediately recognized and can be rejected before the actual insertion in the press.

Scratches
A fine hair-like indentation in the coating surface usually less than 1/8 inch wide; the length varies.

Seal Strength
The force a seal can withstand before it breaks apart.

Set Out
An off quality roll that needs to be reworked. Set outs can come from any point in the manufacturing process. Typical reasons for a set out include: extruder splices, offset in a roll, wrong slit width.

Sewn Closure
A method of closing filled bags with a special sewing machine.

Side/Edge Curl (CD)
The curl occurs at the edge of the web.

Sizing
Adding a specific compound (frequently rosin) that makes the sheet more resistant to penetrations by liquids.

Shear
Force moving two contiguous parts to slide against each other.

Shear strength
The strength of a material or component against the type of yield or structural failure where the material or component fails along a plane as a result of forces acting parallel to the plane.

Slab
Waste at the end of the roll that is normally cut off the core and thrown away.

Slide Zipper
A plastic zipper profile and slider used to close and open the top of a bag. Moving the slider along the zipper profile will open or close the bag top.

Slime Holes
Holes of irregular shape. Around the hole there may also be a discolored area caused by micro-organisms that grow in the warm water at the wet end of the paper machine. If a large organism reaches the press it cannot get through the nip and a hole results.

Slime Spots
Discolored areas of irregular shape caused by micro-organisms that grow in the warm water at the wet end of the paper machine. When a small organism reaches the press station, the organism is mashed to form a slime spot.

Slip Agent
Additive that aids in lubricating the surface of the plastic.

Slip Sheet
8-1/2 x 11" piece of paper/foil with two faced tape on the back and fed into the web while running to get poly weights.

Slitter
A sharp disk which cuts paper into pre-determined widths.

Slitting
Cutting paper by the use of a cutting wheel. Paper may be slit into smaller sheets or a web of paper may be slit into narrower rolls.

Smeared Print
The print on the copy is blurred or smeared.

Smoothness
The flatness of a sheet of paper, which generally determines the crispness of the image printed upon it. The texture of paper or poly sometimes measured with a gauge and given a numerical value.

SOP
Standard operating procedure.

Splice
To connect the ends of two rolls of a raw material together with tape. The connection point of two rolls of raw material. An overlapping joint used to join the ends of webs together.

Static
An electrical charge that is stationary (as opposed to an electrical current in which the charges cause a movement of electrons through a conductor). A coated sheet can become charged with static electricity so that one side of the sheet possesses a positive charge and the other side a negative charge. Since opposite electrical polarities attract each other, a stack of coated sheets that possess static electricity will cling to each other and therefore be more difficult to separate than uncharged sheets. A sheet can retain significant amounts of static for months.

Static COF
The force needed to start an object's movement.

Static Streak
An area on a coated web where static electricity has been discharged that will show an increase in visking; this can be prevented with static eliminator bars. Detection is by methyl violet staining of the web and allowing to air dry.

Streaks
Bands of lighter than normal coating pickup that are wider than about 1/8". The length varies.

Stretch
The elongation of a sheet that occurs, before rupture, when tension is applied to the paper. The measure of stretch is the increase in length of a strip of paper after it is loaded to failure in a tensile tester, stated as a percentage of its original length. The average of a number of measurements of stretch across the web.

Strike Through
A visual defect that looks like the paper is transparent or darker. Caused by hot wax or asphalt being absorbed by the paper rather than staying on the surface.

Substrate
Any material such as paper, film and foil to which adhesives, inks or coating are applied

Sustainability
Incorporating environmentally friendly practices to help maintain the environment.

Swab
A type of brush or paddle used to spread dye or stain on samples.

Tack
The resistance of an ink film to being split between two surfaces, such as between rollers, between plate and blanket, and between blanket and paper; stickiness.

TAPPI
Technical Association of the Pulp and Paper Industry

TAPPI is the leading technical association for the worldwide pulp, paper, and converting industry. Founded in 1915, TAPPI has grown into the world’s largest professional association serving the pulp, paper, and converting industries. TAPPI’s members look to the association for information, education, and knowledge-sharing opportunities. As a professional technical society, TAPPI is in a unique position to offer a wide array of information, products, services, and opportunities unparalleled in the pulp, paper and converting industry.

TCC
Trouble Cause & Correction
Ex: Trouble: Film wrapper (120/120) was not wrapping tight or at all at speeds over 65 ppm. (G-P Line six and Seven 3/15/04).
Cause: COF was too high at 0.30 causing the wrapper to pull back on the under folder at the trailing edge.
Correction: COF was lowered to 0.25 and product now runs at speeds over 100 ppm.

Tearing Strength
The force required to tear a bag.

Telescoped
The roll edge is concave on one side and convex on the other. May exist when the roll is received by the customer or it may occur while the roll is being unwound. Also known as "dished".

Tear Test
Type of bond test performed by slowly tearing a laminated sheet and looking right at the point of tear to see if the poly remains like a film and stretches between the two halves. No film stretch desired (no bridging).

Tearing Strength
The ability of a paper to resist tearing when subjected to rigorous production demands of manufacturing, printing, binding and its conversion from flat sheets into envelopes, packaging materials, etc.

Tensile Strength
The ability of the paper to withstand the stress and strain applied to it before breaking down and pulling apart.

Total Weight
The basis weight of the sample with all coating and laminating sheets together.

Top/Felt Side Curl
The edges are turned away from you.

Transparent
When a material transmits light without diffusion, allowing an object to be clearly seen through it. Measured with an opacity meter.

Tubular Woven Bag
A woven bag that contains no seams.

Unwind
The direction in which the print reads on a roll of paper. The different unwind directions are predetermined and can be found on the "Standard Unwind Roll Chart".

Visking
Test to measure how a future coating or ink will bond to the surface. The surface of poly or wax coated sheet does not readily accept inks, adhesives, or other coatings.

Water Vapor Transmission Rate
The grams of moisture that will pass through an area of 100 sq in of material in a 24 hour period, expressed as gm/100 sq in/24 hr.

Wavy
The appearance of one or both edges of a web in which the sample fails to lay flat on a flat surface.

Web
The paper going through the extruder.

Web Position
Location on a machine or sample that describes front to back; used for sampling and control of cross direction variation.

Wire Side Curl

As you face the wire side of the sheet, the edges are turned towards you.

WIP
Work in process.

ZES
Zero energy state. The machine is completely shut down. All energy sources have been terminated.