Label Printing and Printers Glossary
The wholesale label printing glossary resource for all of your questions.
A - D E - H I - L M - P Q - T U - Z All
Machine Direction: The direction of any material parallel to its forward movement on the press. Also Web Direction.
Magenta: Process red, one of the basic colors in process color.
Magnetic Cylinder: A cylinder used in diecutting that is magnetized to accept and hold in place flexible steel dies. Also used for metal-backed printing plates.
Magnetic Die: A thin, flexible, steel cutting plate that is held on to a base cylinder magnetically. Quite common in EDP label production where identical repeats are frequently used.
Makeready: On printing presses, all operation prior to running; such as mounting plates, adjusting the in-feed, edge guide, putting ink on the fountain, adjusting the impression, setting up the die cutting, color machine, etc. All preparatory operations preceding production.
Mandrel: A shaft upon which cylinders, or other devices, are mounted or affixed. Also unwind or rewind shaft on to which rolls of materials (or labels) are mounted.
Marginal Words: Call outs for directions on various parts of a business form.
Mask: Blocking light from reaching parts of a printing plate.
Master Roll: A full width roll that has finished the primary manufacturing process and is usually untrimmed and unslit.
Matchprint: Trade name for 3M integral color proof.
Material: Usually refers to unconverted stock, pressure-sensitive or not.
Material Space: An area where tape has been used to attach two rolls of material together to form one continuous web.
Matrix: The face material and adhesive surrounding a self-adhesive label, usually removed after die-cutting.
Matte Finish: Dull paper or ink finish.
Mechanical: Camera ready art all contained on one board.
Mechanical Separation: Mechanical art overlay for each color to be printed.
Memory: The property of a material that causes it to attempt to return to its original dimensions after being distorted.
Metal Foil: Thin, flexible layer of metal, such as aluminum, sued as face materials. Thinner gauges are often laminated to paper for strength.
Metalized Film: A plastic or resinous film that has been coated on one side with a very thin layer of metal.
Metalized Paper: A label substrate consisting of a lacquered CIS paper on which a very thin film of aluminum has been deposited.
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.
Micrometer: Instrument used to measure the thickness of different papers.
Micron: A unit of measure. On millionth of a meter or about .00004" (25 microns = 0.001").
Middle Tones: The tones in a photograph that are approximately half as dark as the shadow area.
Migration: The movement of one or more components of the P.S. adhesive into either a substrate or face material.
Mil: Unit of thickness measurement used for thin materials. 1 mil=0.001 inch=100 gauge.
Moire: Occurs when screen angles are wrong causing odd patterns in photographs.
Moisture Content: The moisture present in a material as determined by specified methods.
Moisture Vapor Transmission: A measure of the rate of water vapor transmission through a P.S. label.
Mold Release Agents: Materials used in the manufacture of molded objects to facilitate their removal from the mold. Mold release agents can, in some instances, cause serious adhesion problems.
Mono Web: A brand name for a printed pressure-sensitive label web that is self wound. A release coating is applied over the print so that the adhesive on the back will not stick to the printed surface. The actual die cutting becomes a function of the label application equipment. This process is covered by a patent.
Mottle: Non-uniform coloring or coating of a face material or of the printing on the label.
Moving Beam Bar Code Reader: A device which searches for a bar code pattern by sweeping a moving optical beam through a field of view
Mylar: Dupont's trademark for clear, tough polymeric polyester film.
Negative: The image on film that makes the white areas of originals black and black areas white.
Neoprene Rubber: A polymer of chloroprene, it is used as an adhesive base. Commonly used where oil and gasoline resistance is required. Resistance to swelling action of aromatics (pure and fuels) is poor but much better than natural rubber. Also used to coat doctor or metering rolls.
Nip: Line of contact between two rolls. Often referred to as the pull or draw rolls of a web press.
Non-Reproducing Blue: A blue color the camera cannot see. Used in marking up artwork.
Non-Woven Materials: Usually refers to paper 'tissues' or synthetics such as tynek.
OD: Outside diameter of a cylinder, roller or roll of labels.
OEM: Original Equipment Manufacturer. One who produces a component or components used in the making of a finished assembled product.
Offsetting: Using an intermediate surface used to transfer ink. Also, an unpleasant happening when the images of freshly printed sheets transfer images to each other.
Offset Paper: Term for uncoated book paper.
Offset Printing: Process of indirect printing in which an impression on a flat plate is printed on a rubber-blanketed cylinder, from which it is impressed, i.e. offset, upon the surface to be decorated.
Ok Sheet: Final approved color inking sheet before production begins.
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.
Opacity: The amount of show-through on a printed sheet. The more opacity or the thicker the paper the less show-through. (The thicker/heavier the paper the higher the cost.)
Opaque Ink: An ink that is not transparent and reflects only its color regardless of what colors it overprints.
Ooze: Adhesive moving out of ends of rolls or stacks of sheets causing ends to feel sticky and possible causing material to block. Adhesive cold flow.
Operating Side: That side of a label press on which the printing unit adjustments are located. Opposite of driving side or gear side.
OPP: Oriented polypropylene.
Opticite Film: Trademark of a label film supplied by Dow Chemical (polystyrene type).
Orientation: The alignment of bars and spaces to the scanner. Often referred to as vertical (picket fence) or horizontal (ladder).
Outline Halftone: Removing the background of a picture or silhouetting an image in a picture.
Overlaminating: Applications of a clear film to a label stock for the purpose of protection or to enhance graphic quality, usually done in-line on the press.
Overlay: The transparent cover sheet on artwork often used for instructions.
Overrun or Overs: Copies printed in excess of the specified quantity. (Printing trade terms allow for + - 10 % to represent a completed order.)
Page Count: Total number of pages in a book including blanks.
Pattern Carbon: Special carbon paper used in business forms that only transfers in certain areas.
Pattern Coated: Refers to the width and spacing arrangement of strips of adhesive laid down parallel to machine direction and across the width of pressure sensitive label stock during its manufacture. Also refers to adhesive coating applied in a pattern which is not related to web direction.
Peel Adhesion: The force required to remove a P.S. label from a standard test panel at a specific angle and speed after the label has been applied under specified conditions (Pressure-Sensitive Tape Council). The strip of test material is usually one inch wide, and the angle of measurement can be 90 to 180 degrees from the surface.
Peeler Plate: A sharp edged, flat piece of metal around which the backing or carrier material is threaded, the prime function being a mechanical device which causes a pressure-sensitive label to be dispensed from the backing material.
Penetration: Change of appearance of the face material due to movement of one or more components from the adhesive or the labeled surface. Bleed through, migration
Perfect Bind: A type of binding that glues the edge of sheets to a cover like a telephone book, Microsoft software manual, or Country Living Magazine.
Perfecting Press: A sheet fed printing press that prints both sides of a sheet in one pass.
Perforated: Refers to a series of small incisions make in laid-on labels and/or their release liner to facilitate tearing along a pre-determined line, or for fan folding.
Permanency: A measure of an adhesive's ultimate holding power or bond strength. A permanent adhesive will develop a bond that makes label removal difficult or impossible without distorting the face stock.
Permanent Adhesive: An adhesive characterized by having relatively high ultimate adhesion to a wide variety of surfaces.
Phosphorescent Face: A face material coated with phosphorescent ink that emits light in a visible spectrum.
Photopolymer: Plate material that is photsensitive and upon exposure, its compounds polymerize to form a tough, abrasion resistant surface which becomes the inking media.
Pica: Unit of measure in typesetting. One pica = 1/6 inch.
Picking: Printers nightmare that occurs as the surface of a sheet lifts off during printing. Generally a paper manufactures quality control problem.
Piggyback: Multi-ply P.S. laminate consisting of a face stock; a layer of adhesive; a standard release liner; a layer of adhesive; and a standard release liner. This type of product provides a single label that can be applied to a substrate using the adhesive on the middle liner; then the top ply is removed and applied to a different substrate using the adhesive on the face stock.
Pigment: Finely ground, solid particles used to give color opacity to printing inks and coatings, usually insoluble in such a mixture.
Pin Register: A standard used to fit film to film and film to plates and plates to press to assure the proper registration of printer colors.
Pitch Diameter: The measurement of a gear or cylinder, determined by dividing the circumference by Pi (3.1416).
Plate: The image carrier in letterpress and flexographic printing.
Plate Gap: Gripper space. The area where the grippers hold the sheet as it passes through the press.
Platen Press: Printing press in which a flat surface bearing the paper is pressed against a flat surface bearing the inked type.
PMS: The abbreviated name of the Pantone Color Matching System.
PMT: Abbreviated name for photomechanical transfer. Often used to make position prints.
Point: For paper, a unit of thickness equaling 1/1000 inch. for typesetting, a unit of height equaling 1/72 inch.
Polycarbonate: A high clarity film having the versatility of acetate with the durability of polyester.
Polyester: A strong film having good resistance to moisture, solvents, oils, etc. Usually transparent, although available with opaque ester formed by polymerization or condensation. Excellent strength, clarity and dimensional stability.
Polyester Liner: A polyester film that is silicone release coated. It provides an excellent die cutting surface and is also used on overlaminating films to provide a smooth, glass-like surface of adhesive.
Polyester Overlam: A clear, glossy polyester film coated with clear acrylic adhesive. Can also be supplied with a matte surface.
Polyethylene: A tough, stretch plastic film having very good low temperature characteristics, also used a great deal for producing semi-rigid recyclable bottles.
Polymer: A compound formed by the reaction of simple molecules called monomers, having functional groups that permit their combination to proceed to high molecular weights under suitable conditions. A long-chain molecular structure.
Polypropylene: Similar to polyethylene but stronger and having a higher temperature resistance. Various thermoplastics are polymers of propylene; excellent clarity. Also used in various thickness in the printing of labels as well as backing or liner materials.
Polystyrene: A thermoplastic produced by the polymerization of styrene. The electrical insulating properties are outstanding and the material is relatively unaffected by moisture.
Polyvinyl: Refers to a group of resins formed by polymerizing various vinyl monomers.
Polyvinylidene Chloride: Usually a very thin transparent film with excellent resistance to acids, water and organic solvents. Saran.
Porosity: In paper the degree of air permeability measured in terms of air floe through the sheet.
PostScript: The computer language most recognized by printing devices.
Press Number: A method of numbering manufacturing business forms or tickets.
Pressure Bridge: The steel support mechanically secured over the die stations, through which the pressure screws are threaded.
Pressure Screws: Steel shafts threaded through the pressure bridge which are used to apply pressure (in rotary die cutting station) to facilitate die cutting.
Pressure Sensitive Label: A label product that is processed through roll or sheetfed equipment utilizing a P.S. material which has a protective backing. The manufactured product is generally in the form of rolls, sheets, or fanfolded packs.
Pressure Sensitive Label Stock: The combination of face material, pressure-sensitive adhesive and release liner from which pressure-sensitive labels are manufactured.
Pressure Sensitive Paper: Paper material with self sticking adhesive covered by a backing sheet.
Pressure Sensitive Tape: A combination of a pressure-sensitive adhesive with a carrier. Tapes are either self-wound or utilize release liners or films.
Primary Label: Label that acts as the main identification of a product. Often designed to attract attention and contains information to appeal to a buyer and is usually applied at the time of its manufacture.
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 face material.
Print Treated: A proprietary chemical alteration of the surface by the film manufacturer done during the film making process.
Process Blue: The blue or cyan color in process printing.
Process Colors: Cyan (blue), magenta (process red), yellow (process yellow), black (process black).
Process Printing: Multi-color printing utilizing a variety of printing screens, depth of etch, etc., and usually using yellow, magenta, cyan and black inks to give an optical effect of all colors and hues being present in a composite picture.
Protective Coating: Coating that protects printing on and the face material of a pressure sensitive label from abrasion, chemicals and moisture.
PSI: Pounds per Square Inch.
Pull Tab: Area on a face stock that facilitates easy removal of the label, usually a cut area on a sheeted label. Also called a peel tab or tear tab.
Punched Out Labels: Anvil cut or sheeted labels. Also referred to as metal-to-metal cutting due to the die cutting edge coming in contact with the anvil.