Glossary

Please click on the letters for more information

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

PACKAGING

A coordinated system for the preparation of goods for shipment, distribution and storage.

Refer relevant National Standard.

PADDING

Binding sheets of paper - blank, ruled, etc., together by applying flexible glue or adhesive to one edge of the stack.

PASS

One trip for the material through a production piece of equipment. Certain constructions require additional passes to complete the production.

PATTERN ADHESIVE - See PATTERN COATED

PATTERN COATED

Refers to the width and spacing arrangements of strips of adhesive laid down parallel to machine direction and across the width of pressure sensitive labelstock during its manufacture. Also refers to adhesive coating applied in a pattern which is not related to web direction. Refer LM specification sheets.

PATTERN VARNISH

Spot varnish applied to the printed surface in a desired pattern.

PCS

Print Contrast Signal. A measurement of contrast between the bars and spaces of a symbol. A minimum PCS value is needed for a symbol to be scanned. PCS values can be calculated and displayed automatically on suitable instruments.

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 flakes reinforce each other, the result is a silvery lustre. Effects possible range from brilliant highlighting to moderate enhancement of the normal surface gloss.

PEEL ADHESION

Peel adhesion is the force required to remove a pressure sensitive label from a standard test panel at a specified angle and speed after the label has been applied to the test panel under specified conditions for a specific time. Refer NS for test procedure & LM specification sheets.

PEELBACK

A method of separating a bond of two flexible materials or a flexible and a rigid material that have been bonded with an adhesive. The flexible material is pulled from the mating surface at a 90 or 180 degree angle to the plane in which it is adhered. The stress is concentrated only along the adhesive line of immediate separation. Refer NS & LM specification sheets.

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 labelled surface. Bleed through, migration.

PERFORATED

Refers to a series of small incisions made in laid-on labels and/or their release liner to facilitate tearing along a pre-determined line, or for fan folding (fanfolds). Refer NS.

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 characterised by having relatively high ultimate adhesion to a wide variety of surfaces. Refer NS & LM specification sheets.

PERMEABILITY

The property of a material that allows or resists a substance to pass or flow through it; the rate of such a passage. Refer LM specification sheets.

PET - Recycle code -> 1

Polyethylene Teraphthalate. Clear, tough, solvent resistant, often used as a fibre. Used for soft drink bottles, fruit juice bottles, mineral water bottles and some kitchen and laundry detergent bottles. Refer LM specification sheets.

PHOSPHORESCENT FACE

A face material coated with a phosphorescent ink, that emits light in a visible spectrum.

PHOTOINITIATOR

In Ultra Violet inks, it is the chemical which, when exposed to Ultra Violet light, breaks certain chemical bonds in the system (ink) to start the chain reactions which cause polymer formation. This chemical is commonly referred to as a catalyst. Refer IM.

PHOTOPOLYMER

Plate material that is photosensitive and upon exposure, its compounds polymerise to form a tough, abrasion resistant surface which becomes the inking media. Refer IM.

PIAA

(The) Printing Industry Association of Australia. LATMA is allied with this organisation. Formerly called PATEFA - Printing & Allied Trade Employers Federation of Australia.

PICK

That quality of paper as it relates to the tendency of fibres or particles to be pulled away from the surface when removed from tacky surfaces such as printing plates.

PIECEWORK

Describes a payroll system generally used in production environments where employees are paid according to the actual number of pieces produced in a given time period.

PIGGYBACK

Pressure sensitive constructions that have two release coated liners, two layers of adhesive and a face material which allows a label to be applied, complete with backing, for future or further application. Also it is possible to have carbon inks imbedded in the adhesives. Refer LM specification sheets.

PIGMENT

Finely ground, solid particles used to give colour or opacity to printing inks and coatings, and usually insoluble in such a mixture.

PIN FEED - See FEED SLOTS

PIN REGISTER

The use of accurately positioned holes and special pins or pin bars on copy, film, plates and presses to insure proper register of colours.

PINCH ROLLER - See NIP ROLLER or PULL ROLLER

PIN HOLE

A very small hole which may permit the passage of light, moisture or electrical current.

PINHOLING

Refers to the failure of a printed ink to form a complete film. This condition will become visible by the appearance of small holes in the solid print area.

PIPING

Also known as tunnelling, a condition occurring in an incompletely bonded laminate characterised by release of longitudinal portions of the substrate and delamination of these portions to form these pipelike structures. The material fails to adhere to release paper (liner) or film tightly enough and a line of air forms between them. Usually starts at one edge and works across the web.

PITCH DIAMETER

The measurement of a gear or cylinder, determined by dividing the circumference by Pi (3.1416). Example; 96 teeth gear at 1/8th" = 12" cylinder or 304.8mm.

PLASTICISER

A substance added to materials to impart softness, flexibility, workability, elongation and dispensability.

PLASTICISER MIGRATION

The migration of liquid plasticisers from some plastics into an adhesive and/or face material. Often causes excessive softening or degradation of adhesives.

PLASTICISER RESISTANCE

Some inks can be formulated to resist plasticisers, thereby reducing the effects of plasticiser migration.

PLATE

The image carrier in letterpress and flexographic printing.

PLATE CYLINDER

There are two types of plate cylinders; the integral, with the shaft a permanent part of the body, and the demountable, in which the shaft is removable to receive a multiplicity of bodies of varying diameters, and in some cases face widths. These plate rollers are undercut in their diameter so as to accommodate various thicknesses of mounting tape and plate materials.

PLATE ROLL - See PLATE CYLINDER

PLATEN PRESS

Printing press in which a flat surface bearing the paper is pressed against a flat surface bearing the inked type.

PLIABILITY - See FLEXIBILITY

PLY

Each layer in a multi-layered structure. 3 ply is the common term for timber that is made up of three sheets of wood with the grain at 90 degrees from each other and laminated together to form one piece.

POINT

Printer’s unit of measurement to designate type size. There are 12 points to a pica; approximately 72 points to an inch (25.4mm). Also a term used for an expression of thickness of a sheet of material in one-thousands of an inch increments, ie. 7 point = .007" thick. Note: All computer lettering and type faces are configured in the traditional styles and sizes using point measurements.

POISE

The unit of viscosity, expressed as one dyne per second per square centimetre.

POLAR - See NON-POLAR

POLAR SOLVENT

Solvents with oxygen in their molecule, ie. alcohols, water, esters, etc.

POLARITY

Refers to the relative surface charge of the material, resulting from the molecular structure of the adhered surface.

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 and metallised finish. A clear complex ester formed by polymerisation or condensation. Excellent strength, clarity and dimensially stable.

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. Refer NS & LM specification sheets.

POLYESTER METALLISED FILM

A clear polyester film, vacuum metallised on one side to provide a metallic look. Refer LM specification sheets.

POLYESTER OVERLAMINATE

A clear, glossy polyester film coated with clear acrylic adhesive. Can also be supplied with a matte surface. Refer LM specification sheets.

POLYETHYLENE

A tough, stretchy 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.

POLYMERISATION

A chemical reaction initiated by a catalyst, heat or light, in which monomers and/or oligomers combine to form a polymer.

POLYPROPYLENE

Similar to polythene but stronger and having a higher temperature resistance. Various thermoplastic plastics are polymers of polypropylene; excellent clarity. Also used in various thicknesses in the printing of labels as well as backing or liner materials.

POLYSTYRENE

A thermoplastic produced by the polymerisation of styrene. The electrical insulating properties are outstandingly good and the material is relatively unaffected by moisture.

POLYVINYL

Refers to a group of resins formed by polymerising various vinyl monomers.

POLYVINYLIDENE CHLORIDE

A usually very thin transparent film with excellent resistance to acids, water and organic solvents.

POOR TRAPPING

Condition in wet printing that results when less ink transfers to previously printed ink (wet-on-wet), than to unprinted paper. Also called under-trapping.

POP

Point Of Purchase. The location at which a product is sold, the store or retail counter.

POP DISPLAY

The displays or merchandising units used at the point of purchase.

POROSITY

That property of paper that governs the degree of permeability. ie. The passage of a substance through it.

POST CURE

The continuation of a polymerisation (curing) process within a Ultra Violet ink or coating after exposure to Ultra Violet radiation has been terminated. Usual cure time is 1/40th of a second at 76mm focus from lamp center at 30 meters per minute. However some colours only surface cure during that time, and can take longer for the reaction to complete its cycle. ie. Black cures faster when 10-15% Reflex Blue is added to help the reaction time. Refer IM specification sheets.

POT LIFE - Or SHELF LIFE

The time period during which an adhesive, coating or ink remains effective and workable. Refer relevant Manufacturers specification sheets for shelf life.

PP - Recycle code -> 5

Polypropylene. Hard but flexible, waxy surface. Melts at 145 . Translucent, withstands solvents. Very versatile material with many applications. Used for ice cream tubs and food containers, garden utensils, baby baths and lunch boxes. Refer LM specification sheets.

PRE-SEPARATED ART

Artwork in which the basic layout, register marks and major colour is prepared on illustration board and each additional colour plate is drawn on a separate sheet or film overlay.

PRESS, COMBINATION.

A combination press utilises the various printing and embellishing processes in-line. ie. Coating with Flexography, 4 colours - Rotary Letterpress, 1 colour Foil Stamping, 2 colours Silk Screen, Die Cutting, Punching Perforating and Electronic encoding all in one pass. Usually a combination press allows printing units to be removed and exchanged for other printing units, thereby limiting the number of units and the length of the press. Usually a computer coordinated press that needs the artwork, colour separations and die cutting information fed in so the press can be monitored and controlled from one vantage point utilising a colour monitor.

PRESS, IN-LINE

Press with printing units in-line.

PRESS PROOFS

Printed sections of substrate material made on a press to allow for approval or final corrections before the production printing run is made.

PRESS SLIP COATING

An overall emulsion type coating applied in-line on a press to eliminate spray powder, usually having a good degree of slip additive.

PRESS, STACK

Flexographic press with printing units in horizontal stacks.

PRESS VARNISH

A clear varnish applied in-line on a press. It can be overall or printed in pattern form from a plate to allow for dry laps and other uncoated areas.

PRESS, WEB

Press which prints substrates supplied on rolls. Web presses can deliver product in rolls, sheets, fanfolds or product die cut into single units.

PRESSURE BELT

Applies pressure by continuous hold-down of a label following application on automatic label application equipment.

PRESSURE BRIDGE

The steel support, mechanically secured over the die stations, through which the pressure screws are threaded. Commonly used on flexographic machines.

PRESSURE ROLL (ROLLER)

Holds product to be labelled in place for more accurate placement of label.

PRESSURE SCREWS

Steel shafts threaded through the pressure bridge which are used to apply pressure (in a rotary die cutting station) to facilitate even die cutting. Commonly used on flexographic machines.

PRESSURE SENSITIVE

A term commonly used to designate a distinct category of adhesive tapes, adhesive labels and adhesives which in dry (solvent free) form are aggressively and permanently tacky at room temperature, and firmly adhere to a variety of dissimilar surfaces upon mere contact without the need of more than finger or hand pressure. They require no activation by water, solvent or heat in order to exert a strong adhesive holding force toward such materials as paper, plastic, glass, wood, cement and metals.

Pressure sensitives have a sufficiently cohesive holding and elastic nature so that, despite their aggressive tackiness, they can be handled with the fingers and removed from smooth surfaces without leaving a residue. General trade usage by leading tape manufacturers does not sanction extension of the term "pressure sensitive" to embrace tapes and adhesives merely because they are sticky, eg. fly paper, or merely because they adhere or cohere to a particular type of surface, eg. self-sealing envelopes: and terms other than "pressure sensitive" should be used in such cases to avoid confusion.

PRESSURE SENSITIVE LABEL

Misused terminology - Self Adhesive Label. Labels are not self adhering, and require pressure to help the adhesive ‘grab’ the surface to which they are applied to; therefore Pressure Sensitive is the correct term.

A pressure sensitive label product is the die cut part that has been converted through flat sheet or roll fed production equipment utilising the type of pressure sensitive labelstock which has a protective liner. The end product is produced in the form of either rolls, sheets, fanfolds or singles, or by other techniques that produce like products which have been slit or cut from converted labelstock rolls.

Refer relevant National Standard. Refer TLMI Glossary of Terms 1964-92. Refer Labelstock Manufacturers specification sheets.

PRESSURE SENSITIVE LABELSTOCK

The combination of a face material, pressure sensitive adhesive and release liner from which pressure sensitive labels are manufactured.

PRESSURE SENSITIVE LAMINATE - See PRESSURE SENSITIVE LABELSTOCK

PRESSURE SENSITIVE TAPE

A combination of a pressure sensitive with a carrier. Tapes are either self-wound or utilise release liners or films.

PRICE MARK - (LABELSTOCK)

Special pressure sensitive labelstock used to make pricing gun labels for retail outlets. Refer LM specification sheets.

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 product manufacture. ie. Fruit juice label applied in-line after the bottle has been filled.

PRIME COAT

Base coat applied first to enhance subsequent printing.

PRIME LABEL

A label used to identify and display a product, ie. a major product panel.

PRIMER - Also see BARRIER COAT and TIE COAT

Surface coating applied between face stock and adhesive to improve bond performance and/or prevent bleed of adhesive through the face material.

PRINTABILITY

The ability of a material to accept and hold a printed legend, and especially to resist offset of the printed image when rewound into a roll after printing. Also a collective term used to describe the properties required of all components in the printing process. Refer NS, LM & IM specification sheets.

PROCESS PRINTING

Printing from a series of two or more half-tone plates to produce intermediate colours and shades. In 4-colour process, the colours are yellow, magenta and cyan, with black as the fourth and key colour.

PRODUCTION CONTROL

A system to ensure the efficient use of materials, manpower, facilities and transportation in order to assure the availability of a specific product, in a pre-determined quantity, within a specified time period.

PRODUCTION RUN

The final printing requested by the customer from the original artwork.

PROGRESSIVE PROOFS

Proofs made from the separate images in colour process work, showing the sequence of printing and the result after each additional colour has been applied.

PROOFING PRESS

Press that produces printed progressive proofs.

PROTECTIVE COATING - OVERCOAT - OVERPRINT COATING

A coating that protects the printing and the surface of a pressure sensitive label from either abrasion, sunlight, chemicals (their fumes and dilute solutions) and moisture, or a combination of these.

PSI

Pounds per Square Inch.

PS (RE/EPS) - Recycle code -> 6

Polystyrene. Expanded Polystyrene - EPS. Clear, glassy, rigid, brittle, opaque, semi-tough, melts at 95C. Affected by fats and solvents. In foamed format it is light weight, energy absorbing and heat insulating. Used for yoghurt containers, take-away ‘clamshell’ food containers, fruit boxes and packing. Also used for plastic cutlery, imitation ‘crystal glassware’ and low cost brittle toys. Refer LM specification sheets.

PULL ROLLER - See NIP ROLLER

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.

PVC - See POLYVINYL

Polyvinyl Chloride.