Below is a list of Pressure Sensitive, Label, Specialty Paper, and Graphic Art industry terms:
#
8 Pt. Tag: A pressure sensitive face stock which has a semigloss finish and is 8 mils thick. It is used when stiffness of the label is important. Opacity is high because of its thickness.
A
Abrasion Resistance: The ability of a label surface or other material surface to resist rubbing, scuffing or scratching.
Absorbency: The ability of a label paper or other material to retain liquids or vapors such as printing inks, varnishes, humidity, etc.
Absorption: The process which causes label paper or other material to absorb liquids or vapors.
Accelerated Aging: The process used to determine the behavior of a label paper or other material over a period of time, when subjected to unusually severe conditions.
Acetate: Transparent and matte cellulose films, used as a basis for artwork and overlays.
Acid Free: a material with a neutral pH. The adhesive or product is neither acidic or alkaline. This is an important property for labels that need to last forever. Acidic materials tend to yellow with age.
Acrylic: A water-soluble polymer used in paints to make them dry both tough and flexible.
(Peel) Adhesion: The amount of adhesion determined by measuring the force required to remove or “peel” a label or adhesive coated material from a test substrate at a specified angle, speed and condition. See Peel
(Residual) Adhesion: The amount of adhesion determined by measuring the force required to remove or “peel” a label or adhesive coated material from a silicone coated substrate under specific conditions.
(Specific) Adhesion: The amount of adhesion determined by measuring the force required to remove or “peel” a label or adhesive coated material from a substrate under exact circumstances.
Adhesive: A coating used to bond label material to a substrate. Various adhesives are available to satisfy a wide range of applications.
(Acrylic) Adhesive: An adhesive composed of specific synthetic polymers or co-polymers, which are inherently pressure sensitive. This adhesive works well with plastics, metal, corrugated and wood.
Adhesive Bleed: When an adhesive has oozed or “pushed-out” beyond the label stock and the liner.
Adhesive Migration: This occurs when the adhesive moves through what seems to be a solid object. Adhesive migration could cause adhesive contamination for the contents of the labeled package.
(Hot Melt) Adhesive: An adhesive that when heated turns to a liquid and gains strength upon solidification and crystallization when cool. This adhesive is typically used when applying labels on in-line packaging and labeling machines.
(Microsphere) Adhesive: An ultra-removable adhesive that is powered by tiny spheres that are easily repositionable and remove without a trace. Microsphere adhesive has an excellent durability and life cycle. It is suitable for a wide range of applications.
(Permanent) Adhesive: An adhesive characterized by having high initial tack or adhesion to the surface of a substrate. A label with permanent adhesive cannot be removed intact or will require a substantial amount of force to be removed.
(Pressure Sensitive) Adhesive: An aggressive adhesive that with the application of light pressure provides instant adhesion and does not require glue, water or heat to adhere to the surface of a substrate.
(Removable) Adhesive: An adhesive characterized by having low initial tack or adhesion to the surface of a substrate. Removable adhesive allows the label to be removed from most substrates without damaging the surface or leaving adhesive residue. A label with removable adhesive will become permanent on a substrate over a period of time.
(Repositionable) Adhesive: An adhesive characterized by having low initial tack which allows for easy removal and repositioning within a short period of time after being applied. A label with repositionable adhesive will become permanent on a substrate over a period of time.
Adhesive Residue: The adhesive that remains on the surface of a substrate after a label is removed.
(Rubber-based) Adhesive: An adhesive that is comprised of synthetic or natural rubber and other compounds which creates a pressure sensitive adhesive.
(Solvent-based) Adhesive: An adhesive coating process that uses solvents in the coating process.
(Water-removable) Adhesive: An adhesive that can be cleanly removed from a substrate when placed in contact with water.
Against the Grain: Feeding label paper at a right angle or opposite to the grain direction of the face stock.
All temperature Adhesive: A common designation for a pressure sensitive adhesive designed for application between room temperature and freezing conditions. In spite of its name, it will not apply successfully at all temperatures. Generally all temperature adhesives are only used when application is done at a wide variety of temperatures because they are more expensive than permanent adhesives. See also cold temperature adhesive and freezer adhesive.
Anchorage: The securing or adhering of an adhesive, coating or ink to a substrate.
Animal Glue: Another name for bone glue. It was the original type of strong gum in water re-moistenable adhesives. See also strong gum and bone glue.
Appearance: The visible aspects such as color, finish and formation of a paper or substrate.
Application Temperature: A range in temperature that is required at the time of application.
Adhesives have a minimum application temperature and should be tested on the substrate under the application conditions.
B
Back Splits: Linear cuts through the liner of a pressure sensitive label material that allows for strips to be removed individually.
Balanced White: A face stock or substrate that is manufactured to reflect all the visible wavelengths in the spectrum equally.
Band Label: A label that fully wraps around the surface to which it is applied. An example would be sock band labels. Usually there is a slight overlap and the adhesive sticks to itself.
Barrier Coat: A coating that prevents absorption or interaction between the substrate and any subsequent coating.
Basis Weight: The weight in pounds of a ream (500 sheets) of paper cut to a given standard or basic size for that grade (e.g. 500 sheets 25 x 38 of 60 lb. coated book paper weighs sixty pounds).
Bleed: When a printed image goes beyond the trim edge of the label paper or substrate.
Bleedthrough: Migration of materials from an adhesive or substrate into a face material, resulting in a mottled appearance of the face stock with possibly detrimental effects to the adhesive.
Blind Embossing: A design that is stamped without metallic leaf or ink, giving a bas-relief effect.
Blistering: A bubbled appearance due to partial delamination between two or more surfaces.
Blocking: Undesirable adhesion where the labels stick to the back side of the liner above them. Usually due to adhesive flow, incomplete die-cutting of the adhesive, improper drying of inks or improper drying or curing of coatings. With gum paper the water sensitive adhesive can stick to the face stock. Sometimes slamming down a package can relieve it.
Body: A term used to define the thickness or viscosity of ink.
Bonding: The uniting of two items.
Brightness: The percentage of light reflected from the surface of the face stock or substrate.
Bronzing: The process of printing with a sizing ink and the application of bronze powder to produce a metallic look.
Bulk: The degree of thickness in a number of sheets of paper. Bulk and caliper are related, but not numerical equivalents.
Butt Cut Label: A knife cut label in which the knife cut is made through the face stock, across the full width of the label. Most uses are for hand application of the labels.
C
C1S: An abbreviation for coated one side. It usually refers to clay coated papers that are only coated on the print side. Since adhesives cover the other side, many clay coated papers we use are C1S. If product was C2S, it would be clay coated on both sides. Typical uses for this type of product would be magazines and brochures.
Calendered: Label paper or material that has gone through the process of calendering. The face stock or other material is passed between rollers which increase the smoothness and gloss of its surface.
Calendering: A process of compressing and smoothing paper between heavy metal rollers. Calendering makes the paper less absorptive to ink by giving it a more dense and even surface. Paper can be calendered to the following finishes: High gloss, gloss or semi-gloss.
Caliper: The measured thickness of a single sheet of label paper or material to the closest ten-thousandths of an inch (which is equivalent to mils or points).
Cast Coated: A paper or face stock with a very high gloss, enamel-like finish that has a clay-based coating which is dried with heat and pressure against a highly polished cylinder.
Cast Coating: A process which gives paper an extremely glossy enamel-like finish. These are created by bringing the paper in contact with chromium drums. Print surface is exceptionally smooth. Cast coated papers have the highest gloss levels of any clay coated paper. KromeKote is an example of a cast coated paper.
Chemical Resistance: The resistance of a label to the deteriorating effects of exposure to various chemicals under specified conditions.
Coated: A face stock or other material that has a coating (e.g. clay, carbonates, latex) applied to the surface to improve its characteristics (e.g. whiteness, opacity, smoothness, printability, gloss level).
Coated Stock: Any face stock or other material that has a coating applied to the surface to improve its characteristics. See Coated
Coating: A layer of minerals applied to the surface (one or both sides) of a paper or other material to improve its characteristics (e.g. whiteness, opacity, smoothness, printability, gloss level).
Cockling: The rippling or wrinkling of a label paper or other material making the surface uneven and unusable.
Cohesive Strength: The internal strength of an adhesive, often determined by the force required to divide it or separate it internally.
Cold Temperature Adhesive: A pressure sensitive adhesive designed for application in refrigerator conditions to a cold substrate. Most cold temperature adhesives will not work in true freezer conditions.
Cold Flow: The high resistance to flow of a coated adhesive due to static stress at ambient temperatures.
Color Fastness: The ability of a label paper or other material to maintain or hold color under various situations such as storage, when exposed to light, heat or other external conditions.
Conformability: The ability of a label paper or other material to correspond in form or character to the contours of a curved or rough surface.
Contrast: The percentage of tonal gradation between the high, mid and low tones ranging from black to white.
Copier Labels: Lightweight grades of good quality and dimensionally stable label papers engineered to feed automatically through copier machines.
Corona Treatment: An electrical discharge which is used to raise the critical surface tension of substrates to facilitate good wet-out of applied materials or coatings.
Crack ‘N Peel: A diagonal scoreback liner developed by Avery/Fasson around 1957.
Cross Direction: The direction across the grain. Paper is weaker and more sensitive to changes in relative humidity in the cross direction than in the grain direction.
Curl: The curving or bending of a label paper or other material due to structural or external conditions including humidity, heat and moisture absorption.
Cut-Off: The point where a sheet of label paper or other material is cut from a roll.
Cutting Tolerances: Allowable variations in the sizes of cut labels. Straight-cut labels have tolerances of ± 1/32 inch (0.8 mm); die-cut labels have tolerances of ± 1/64 inch (0.4 mm).
Cut-to-cut tolerance: The allowable variation in size on labels between the edge of the label and the edge of the printed image on the label.
D
Delamination: The separation of material into layers in a direction approximately parallel to the surface. May be used to describe any splitting of a material in a plane parallel to its surface.
Density: The amount of light absorption or opacity of a label paper or other material.
Dextrin: Any of various soluble polysaccharides obtained from starch by the application of heat or acids and used mainly as adhesives and thickening agents. In conventional gum, this is a type of adhesive that is primarily vegetable in basis.
Die: A device used for cutting out a shape or stamping an image on label paper or other material.
Die-Cut: The line of severance between a pressure sensitive label and its matrix or adjoining label made by the cutting edge of a die.
Die-Cut Label: A pressure sensitive label mounted on a release liner from which the matrix has been removed.
Die-Cutting: A method utilizing a die or sharp steel rule to cut a specified shape out of label paper or other material.
Die-Stamping: An intaglio process for printing from engraved lettering or designs on copper or steel.
Digital Printing: Printing by plateless devices imaged by digital data driven imaging systems. Digital printing runs from computer to press (or printer) to output. Also called non-impact printing.
Dimensional Stability: The ability of label paper or other material to resist dimensional change resulting from change in moisture content or relative humidity.
Direct Thermal: A type of non-impact printing that uses heat to darken printed images. There is a thermal coating that darkens with application of heat. Advantages of this printing method are high resolution, quiet printing and inexpensive printers. The main disadvantage is that the images are not permanent. They tend to fade with time and can darken when contacted with certain liquids. Direct thermal paper is more expensive than other types of white paper.
Draw-Down: A method used by ink manufacturers and suppliers to determine the characteristics of a specific ink on a specific label paper or other material.
Dry Gum: A water sensitive adhesive that has a dull finish. It is more dimensionally stable than conventional gum. See also water sensitive. Generally it is paper stock coated on one side with an adhesive that is moisture activated.
Dull Laminated Foil: This is a pressure sensitive face stock that is paper laminated foil with a matte appearance. It is available in both silver and gold colors. See also paper laminated foil.
Dyne Level: Dyne is a measurement of surface tension or energy. The level is the actual reading of the critical surface tension. Low dyne levels indicate a low surface energy which can contribute to poor ink adhesion.
E
Edge Lift: The lifting or separating of the edge of a label from the application substrate.
Electronic Printing: The means of producing images using plateless, non-impact systems.
Embossing: The process used to decorate a label paper or other material by impressing a surface with dies to produce a raised or depressed image.
Enamel: A term used to describe the finish on a coated label paper or other material as well as the coating used on the label paper or other material.
English Finish: A face stock grade with a smoother, more uniform surface than standard machine finishing.
Engraving: An intaglio printing process which creates a raised image on the surface of the label paper or other material.
F
Face stock: The primary surface material that forms the actual label of label paper. This surface includes paper or tag stock, foil, film, fabric or cloth.
Face Splits: Linear cuts or slits through the face stock.
Fine Paper: Papers primarily intended for printing and writing applications. It is the opposite of coarse paper in smoothness of printing paper. Sometimes, merchants that specialize in printings grades are called fine paper merchants. See also coarse paper.
Finish: A term used to describe the surface of label paper or other material.
Finishing: Operations preformed after printing (post-press) which include trimming/cutting, die-cutting, gold stamping, folding, etc.
Flexibility: The ability of a face stock or other material to conform to a curved surface.
Flexography: A printing process that prints from a relief image using a rubber or plastic plate and fluid inks.
Fluid Ink: An ink with low viscosity (Also referred to as liquid ink).
Fluorescent Paper: A paper coated with a pigment which not only reflects a visible wavelength, but is activated by most of the remaining absorbed light to re-emit it as a color of longer wavelength which results in reinforcement of the reflected color. They almost seem to glow.
Foil: A dual component structure composed of extremely thin caliper metal (most common is 0.009mm) laminated to paper for added strength when used as labels, box-wrap, etc.
Format: The size, style, layout, margin, etc. of a label.
G
Gloss: The measure of light reflected from the surface of a label paper or other material.
Glue-applied Labels: A type of preprinted label that is glued to the application substrate. Typically used on products in the beverage, cosmetic, food, household, industrial and pharmaceutical industries.
Grain: The direction in which the fibers of the paper lie directly corresponding to the direction in which the paper travels through the paper machine.
Grain Long: When the grain direction of the label paper or other material runs parallel to the longest dimension of a sheet.
Grain Short: When the grain direction of the label paper or other material runs parallel to the shortest dimension of a sheet.
Grammage: The metric term used for the basis weight of paper. It is the weight in grams of a square meter of the paper (g/m2).
Gravure: A printing process which employs a cylinder with tiny ink reservoirs etched on its surface. The recessed areas are like wells that form the image as paper passes through.
Gripper: Metal fingers in a sheet-fed printing press that hold and guide the label paper or other material as it passes through.
Gripper Edge: The leading edge of the label paper or other material that leads through the printing press.
Gummed Paper: See Dry Gum
H
Heat Resistance: The characteristic of a label paper or other material which inhibits change (e.g. physical, chemical) when exposed to extreme temperatures.
Heat-seal Labels: Labels characterized by an adhesive that activates when heated on a labeling machine.
High (Hollow) Die: This is a device used to cut specified shapes out of label paper or other material where the die is open allowing the die-cut material to stack up within the die itself.
High-Gloss: A term used to describe the finish of a face stock or other material characterized by the reflectance of white light or gloss of the surface. See Cast Coated
Holdout: See Ink Holdout
Humidity: The amount of moisture or dampness in the air.
I
Impression: A term used to describe the transference through a printing process of an image to label paper or other material.
Initial Tack: The measure of instant adhesion a pressure sensitive label has when applied to a surface.
Ink Holdout: A term used to describe the amount of ink absorption on a label paper or other material. The higher the ink holdout the higher the print gloss.
Ink-Jet Labels: Labels designed to run smoothly on ink-jet printers.
Intaglio Printing: A method of printing in which the image is engraved or etched below the surface as in gravure.
Integrity: A term used to describe the quality of the paper surface (finish).
J
Job Lot: Rejected material. It could have been rejected by the manufacturer or by a customer. There is usually some type of quality defect in job lot material. It is sold at a reduced price because of the defect.
Jog: A procedure used to align the edges of a stack of label paper or other material by shaking or vibrating it on a machine or by hand.
K
Kimdura: A polypropylene Kimberly-Clark face stock. It offers consistent printing compared to vinyl because it does not need to be top coated for printing. It is guaranteed for one year of outside exposure and may last longer without degradation. We stock the FPG 80 grade which has a caliper of 3.2 mil.
Kiss-Cut: A method of cutting through the face stock of label paper or other material, but not through the liner.
Kraft: A paper or board containing unbleached wood pulp (brown in color) made by the sulfate process.
L
(Butt-Cut) Labels: Pressure sensitive labels that share a common cut line and have no space between them.
(Die-Cut) Labels: Pressure sensitive labels that are kiss-cut and formatted to include space between each label. There are square corners, rounded corners, and special shapes.
(Fan-Folded) Labels: Labels manufactured in a continuous format that are folded in a zig-zag configuration.
Label Laminate: A label laminate consists of face stock, adhesive and silicone-coated backing paper (liner).
Label Paper: Any paper stock that has an adhesive applied to it.
Lacquer: A clear protective coating applied to the surface of a printed label paper or other material.
Laser: A type of computer printing that uses a dry toner which is fused to paper by a combination of heat and pressure. Laser printers offer high print resolution, quiet operation and some have high speed output. The heat and pressure that occurs during printing can pose problems for adhesive coated labels. Special pressure sensitive adhesives are selected for compatibility with the harsh printing environment.
Laser Labels: Labels specifically engineered to run smoothly through laser printers.
Laser Printing: A printing process that uses a narrow band width, intense light beam to produce an image from digital data through electronic impulses.
Latex Impregnated Paper: Paper manufactured in a way to impregnate or saturate the paper fibers with latex. One method of manufacture called impregnation combines the latex with the fibers in the beater prior to formation of the sheet. The second method saturates the preformed web with a properly compounded latex. The latter is referred to as latex saturated paper. These grades are characterized by strength, folding endurance, resistance to penetration by water, flexibility, durability and resistance to abrasion.
Lay Flat: A characteristic of label material with good non-curling and low distortion qualities.
Laminate: When two or more materials are layered to form a unique product.
Lamination: A protective film that is bonded to a printed sheet by heat and/or pressure.
Laser Labels: Labels engineered to run smoothly through laser printers.
Letterpress: The original method of printing with type, that transfers an image directly to the label paper or other material. It is a printing process that uses raised type. Generally the smoothness of paper used is very important to quality printing. Uniformity of caliper is also important. Rotary letter press printing is higher quality than can usually be achieved by flexographic printing.
Letterset: An offset letterpress printing process which transfers a relief image to a blanket and then to the label paper or other material.
Liner: A release coated base stock (frequently silicone-based) applied to the adhesive side of pressure sensitive label material, protecting the adhesive from contamination prior to application.
Lithography: A printing process in which the image to be printed is rendered on a flat surface, as on sheet zinc or aluminum, and treated to retain ink while the non-image areas are treated to repel ink.
Long Grain: The grain direction of label paper or other material that runs parallel to the longest dimension of a sheet.
Look-Through: The structural appearance of the sheet of paper when viewed by transmitted light. See Opacity
M
M Weight: The weight of 1,000 sheets, in pounds, of a basic sheet size.
Machine Direction: The direction the paper travels through the paper machine which is also the direction of the grain in label paper and other material.
Matte Finish: A term to describe the surface of a coated label paper or other material that is characteristically dull and without gloss, for low glare appearance.
Metalized Film: A plastic or resinous film that has been coated on one side with a very thin layer of metal. See metalizing.
Metalized Paper: A paper that has been coated on one side with a very thin layer of metal. See metalizing.
Metalizing: The application of a thin coating of metal to a non metallic surface. They are similar in appearance to foil, but do not have a solid layer of aluminum.
Migration: (Also known as bleed) The movement of one or more components of the pressure sensitive adhesive into either a substrate or face material.
Moisture Content: The percentage of moisture in a label paper or other material in relation to its total weight.
Mottle: A term used to describe label paper or other material that has a spotty or blotched appearance.
N
Non-Impact Printing: See Digital Printing
O
Offcut: The remaining, usable label paper or other material left when sheets or rolls are cut to the required size.
Offset: An unintentional transfer of wet ink from a printed sheet to another surface in contact with it.
Offset Gravure: An offset printing process involving the transfer between various plates (gravure plate, plate cylinder and rubber plate).
Offset Paper: Paper produced for use on offset presses.
Opacity: The quality or property of label paper or other material of being opaque, that reduces the amount of “show-through” or light that passes through.
Opaque: Label paper or other material that is impenetrable by light and is neither transparent or translucent.
Opaque Ink: Ink used to completely block out an image or other information and that reflects only its color.
Orange Peel: A textured appearance of a label after being overlaminated.
Overprinting: Printing that is done over a previously printed area.
Over-Run: Extra or additional pieces printed in excess of the quantity ordered.
P
Paper: A material made of cellulose pulp, derived mainly from wood, rags and certain grasses, processed into flexible sheets or rolls by deposit from an aqueous suspension.
Paper Grades: The classification of paper based on the end use, the pulp used and the treatment of the paper.
Paper Pulp: A mixture of celluose material, such as wood, paper and rags, ground up and moistened to make paper.
Parchment: Historically, a sheet made from skins of goats and other animals. Today, parchments are simulated by treating the base stock with various chemicals.
Parent Sheet: A sheet that is larger than the cut stock of the same paper.
Pattern Gummed Adhesive: An adhesive coating that alternates strips of adhesive/no adhesive parallel to the machine direction. The areas of no adhesive are frequently used as “lift-tabs” for order picking type labels.
Pattern Release: Selectively applying alternating strips of release coating/no release coating in a machine direction pattern that results in a permanent face stock/release liner bond in the non-release areas.
Peel: The force required to remove a label. Also see Adhesion
Photo Gravure: A method of printing by an engraving process.
Picking: The lifting of the paper surface during printing which occurs when the splitting force (tack) of the ink is greater than the surface strength of the paper.
Pin-Fed Labels: Continuous labels engineered to run smoothly on dot matrix printers.
Pin Registration: The use of accurately positioned holes and special pins or pin bars on copy, film, plates, presses and labels to insure proper registration of the image or information.
Plasticizer: An ink additive that adds flexibility, softness and adhesion.
Pli-A-Print: A latex-impregnated, flexible stock manufactured by Avery Graphics, suitable for exposure to moisture.
Polyester: A strong film having good resistance to moisture, solvents, oils and many other chemicals.
Premium: Any paper that is considered better than #1 by its manufacturer.
(Flat-Bed) Press: A lithographic press used for press proofing.
(In-Line) Press: A printing press with the printing units in-line.
(Perfecting) Press: A printing press which can print both sides of the paper in one pass through the press.
(Sheet-Fed) Press: A printing press which prints on sheets of paper.
(Stack) Press: A flexographic press with printing units in stacks.
Pressure Sensitive: Any material or substrate that with the application of pressure, by hand or machine, provides instant adhesion to another substrate and does not require glue, water or heat.
Pressure Sensitive Paper: Any label paper or similar material with an adhesive coating, protected by a backing sheet (liner) that when the liner is removed, will adhere instantly to most substrates with the application of pressure, by hand or machine.
Pressure Sensitive Label: A self adhesive label construction composed of face stock, pressure sensitive adhesive and release liner. The official TLMI definition is A pressure sensitive self adhesive label product is a die-cut part that has been converted through roll fed production equipment utilizing the type of pressure sensitive self adhesive material which has a protective backing. The end product is produced in the form of either rolls, sheets, fanfold, or by other techniques that produce like products which have been slit or cut from the converted rolls. Sheet PS product is also made into labels that would be considered pressure sensitive labels.
Pressure Sensitive Label Stock: The combination of face stock, pressure sensitive adhesive and release liner from which pressure sensitive labels are manufactured.
(Vertical) Press: A letterpress cylinder press on which the plate is mounted on a vertical plate and paper is fed over a cylinder.
(Web) Press: A press which prints on rolls of paper.
Primer: Coating applied to the face material on the side opposite to the printing surface to improve anchorage of the adhesive and prevent migration of adhesive components into the face material.
Print Quality: The properties of the paper that affect its appearance and the quality of reproduction.
Printability: A broad paper characteristic which refers to a paper’s suitability for presswork.
Process Printing: Printing from a series of two or more halftone plates to produce intermediate colors and shades. In 4-color process the colors are yellow, magenta, cyan and black.
R
Reducers: Varnishes, solvents, oily or greasy compounds used to reduce the body and/or viscosity of inks for printing.
Register: The exact corresponding placement of successively printed images and/or successively die-cut labels.
Release Coat: Material coated on the liner which allows pressure sensitive labels to release.
Release Liner: The component of the pressure sensitive laminate which functions as the carrier for the label. It protects the adhesive prior to application, and it readily separates from the label immediately before the label is applied to the substrate. Also called backing sheet or liner.
Relief Printing: Printing from raised surfaces.
Removability: A relative term applied to pressure sensitive adhesives to describe the force under which the adhesive can be separated from the substrate. A removable label would be one in which no damage or staining occurs to the substrate or the face stock on separation from substrate. This action is relative to substrate and application conditions. Few removable adhesives are removable from all surfaces.
Residue: Adhesive left on a substrate when a label is removed.
Resolution: Means of quantifying output quality of electronic devices using the number of dots or spots per inch.
Recycled Paper: Paper of which the fibrous composition contains a majority of recovered or recycled cellulose fibers (RCF).
Rub-Proof: An ink that has dried so it does not smear with normal handling.
Runnability: The ability of a label paper or other material to run on press without problems.
S
Satin Finish: A smooth, delicately embossed finished paper with sheen. Also called Silk.
SC (Supercalendered) Paper: Paper that has undergone a mechanical treatment which aims to obtain a very homogeneous surface. Normally made from mechanical/ground wood pulps.
Score: To impress or indent a mark with a rule in the label paper, liner or other material to make folding easier.
Scoreback Liner: Crush scoring on the liner of pressure sensitive for peeling off.
Scoring: To impress label paper or other material with a rule for the purpose of making folding easier.
Screen Printing: A printing process in which ink is spread across an open-mesh fabric screen held in a frame where a squeegee is used to form the image. A stencil placed over the screen blocks ink from passing to the non-image areas.
Self-Adhesive Papers: Used essentially for labeling purposes, the grade has a self-adhesive coating on one side and a good surface for printing on the other. The adhesive is protected by a laminate which enables the sheet to be fed through the printing machine, the laminate subsequently being stripped when the label is applied.
Service Temperature: The temperature range that a pressure sensitive label will withstand after a 24 hour period on the substrate. The range is expressed in degrees of Fahrenheit or Celsius.
Shelf Life: The period of time during which a product can be stored under specified conditions and still remain suitable for use (normally one year).
Show-Through: The undesirable condition in which the printing on the reverse side of a sheet can be seen through the sheet under normal lighting conditions.
Silk Finish: See Satin Finish
Slitter: Rotary knife used to slit a paper web into specified width or to trim the outer edges.
Slitting: A term to describe the process of cutting printed sheets by the cutting wheels of a printing press.
Smoothness: Texture of the surface of label paper or other material, also called its finish.
Smudge Resistance: The resistance of a printed surface to smearing.
Solvent Resistance: The resistance of a pressure sensitive label to the action of specific organic liquids.
Specialty Papers and Boards: This is a paper trade definition applied to such grades as off-machine coated, laminated, impregnated, etc. as distinguished from printings and writings etc. and other grades which do not require further processing. Specialty papers and boards are often the raw materials for use by other industries. The electrical and instrumental industries are examples.
Split Back: Cuts through the release liner for the purpose of removal of the liner. These cuts are all the way through the liner rather than compressed scores which only weaken the liner, but do not break it.
Stability: The quality of paper to maintain its original size when it undergoes pressure and moisture changes.
Stagger Cutting: A process of cutting many sheets from the same parent sheet in which the smaller sheets have different grain direction. Also called dutch or bastard cutting.
Static: Electricity generated by friction as paper comes into contact with other paper, metal, wood, etc.
Static Cling Material: Specialty materials without adhesive that adhere or “cling” to substrates through electricity generated by friction (static).
Stiffness: Rigidity, resistance to bending and inflexibility.
Stock: Label Paper or other material to be printed.
Straight-Cutting: Cutting stacks of labels on a guillotine or flat cutter.
Strike-Through: See Show-Through
Strong Gum: A type of conventional gum designed for good adhesion to corrugated. It was originally an animal glue, but now has chemical additives to promote adhesion. It is slightly more expensive than dextrin adhesives, but less expensive than dry gum adhesives. See also conventional gum, dextrin, animal glue, bone glue and dry gum.
Substrate: The surface to which a label is applied. Converters also sometimes refer to the face stock being printed as the “substrate”.
Supercalender: Machine for giving paper a very smooth surface by passing it through a series of alternate metal and composition rolls, revolving at high-speed with pressure.
Surface Energy: A measure of how well an adhesive wets out over the surface of the material which it is applied. Materials with Low Surface Energy (LSE) do not allow adhesives to wet out, while materials with High Surface Energy (HSE) provide excellent wet out, thus providing better adhesion. Rubber based adhesives usually provide better adhesion to LSE surfaces. There are also modified acrylic adhesives that have excellent tack.
Surfaced (Paper): Paper having undergone a coating process in order to improve the characteristics of its surface.
Synthetic Papers: Any petroleum-based waterproof papers with high tensile strength.
T
Tack (Label Paper): The property of a pressure sensitive label which causes it to adhere to a surface instantly with minimum pressure and contact time.
Tack (Ink): The degree of pulling power (stickiness) in printing ink.
Tag: A dense, strong paper stock.
Tag Labels: Labels on heavy paper or tag stock.
Tail-End Hook: Mechanical curl that develops at the back edge of label sheets due to heavy solids close to the back edge of the sheet.
Tensil: A 7 mil white, porous polyolefin film providing excellent printability and durability, and is suitable, when combined with the proper adhesive and liner, for most digital print techniques.
Tensile Strength: The ability of a sheet to withstand tension. Paper possesses greater tensile strength in its grain direction.
Thermography: A printing process whereby slow drying ink is applied to paper and, while the ink is still wet, is lightly dusted with a resinous powder. The paper then passes through a heat chamber where the powder melts and fuses with the ink to produce a raised surface.
Thickness: An aspect of the structure of a sheet of label paper or other material seen by transparency.
Tooth: A characteristic of paper, a slightly rough finish, which permits it to take ink readily.
Top Coating: A coating done on top of a face stock to improve ink receptivity, or to make the label more durable. Nitrocellulose is used as a top coating for offset printing. Acrylic top coated material will not offset print well. On the other hand, acrylic top coatings are compatible with both water based and solvent flexo inks. Top coating on direct thermal protects the label from liquids that could darken the image. Some films are also top coated to enhance printing characteristics.
Translucency: Ability to transmit light without being transparent.
Transparent Ink: Inks that do not block out the colored inks that they print over, but instead blend with them to create intermediate colors.
Treated (Paper): Paper treated mechanically in the paper machine in order to improve the smoothness and uniformity of the two sides; the paper is rubbed, smoothed and calendered.
Tyvek: An extremely high tear strength material made from synthetic spun-bonded polyolefin fibers.
U
Up: A term used to describe the number of images printed on a large size sheet to take advantage of full press capacity; two-up, four up, etc.
UV Coating: A very slick, glossy coating applied to the printed paper surface and dried on press with ultraviolet (UV) light.
UV Ink: Ink specially formulated to dry quickly with ultraviolet (UV) light while still on press.
Uncalendered: Papers that are not smoothed by going through the calendering process.
Under-Run: The final number of pieces printed that is less that the quantity ordered.
V
Varnish: A thin, clear coating of mixtures of natural or synthetic resins and drying oil applied to a printed sheet for protection or appearance.
Varnishing: Process consisting of applying varnish or lacquer on a material or a composite. As with the application of a film, varnishing aims to protect the printing and to increase the paper’s glossiness, as well as improve its barrier properties.
Vellum Finish: A full, toothy finish which is relatively absorbent for fast ink penetration. Text papers in books frequently have a vellum finish. Vellum would not be as smooth as a smooth offset or English Finish grade.
Viscosity: The resistance to flow.
W
Waterless Plate: A printing plate using silicone coating in non-printing areas so it can be run without dampening solution on the press.
Waterless Printing: A printing process that uses waterless plates which eliminate the need for an ink-water balance.
Water Sensitive: A water moistenable adhesive that activates when water is applied. There are two major types of water sensitive adhesives — dry gum and conventional gum. Generally water sensitive adhesives only stick to paper and paper products. Some will adhere well to glass. See also dry gum and conventional gum.
Weatherability: The capability of a label or other material to withstand the effects of outdoor conditions such as sunlight, heat, cold, humidity, rain, snow and time.
Web: The roll of paper that is used in web or rotary printing.
Whiteness: The paper is perceived to be white due to high clarity, elevated diffusion and minimum perception of hues.
With the Grain: Feeding paper into a press parallel to the grain of the paper. Also called short-grain.
X
Xerographic Paper: Papers made to reproduce in copy machines and laser printers.
Xerography: The printing process used by photocopying machines. Electric charges create the image on an electrophotographic surface that works as a plate. This surface is cleared after each copy is made, and used over again for the next copy.