0 – 9


Updated 10 June 2010

R/Nr Glass – Refillable/non-refillable glass containers.

R/Nr PET – Refillable/non-refillable PET containers.

R/PEN – Refillable PEN containers.

Radiant Energy – A form of energy consisting of the electromagnetic spectrum, which travels at 299,792 kilometres/second or (186,206 miles/second) through a vacuum, and more slowly in denser media (air, water, glass, etc.). The nature of radiant energy is described by its wavelength or frequency, although it also behaves as distinct quanta (“corpuscular theory”). The various types of energy may be transformed into other forms of energy (electrical, chemical, mechanical, atomic, thermal, radiant), but the energy itself cannot be destroyed.

Radicals – (Free Radicals) A molecule which has at least one unpaired electron.  In polymers, such a species will be formed, most probably, as a result of chemical bond breakage by heat or light energy.  These free radicals are very active, and in their attempt to pair their lone electron, are capable of breaking other chemical bonds.  Thus, they can cause degradation in a polymer.

RAFT technology – see ‘reversible addition-fragmentation chain transfer’ technology

Rag pulp – Papermaking pulp made from textile waste, cotton, hemp or flax.

Ragger – A device which removes rags and similar contaminants from recycled material during the pulping operation. Normally installed on a beater machine.

Railroad Tracks – A streak developed by oscillation of a nicked doctor blade, resulting in a heavy, wide line printed on the web at the ends of the stroke, with fine lines running in between.

Railroading – Printing of a continuous mark or line in the non-image areas of a design, often resulting in the marking or scratching of a cylinder. Can be caused by particles lodged behind the doctor blade.

Random Proof – A press proof or off-press proof that is made from just one image, to check its appearance before it is stripped into position with other images in a page layout.

Rankine – An absolute temperature scale used by engineers, in which one degree Rankine is 5/9 of one degree on the Kelvin scale. Use of this scale permits calculations involving absolute temperature by adding zero degrees (460 degrees Rankine) to standard Fahrenheit temperature readings. It is also convenient since any Rankine value can be translated to Fahrenheit by subtracting 460.

Raster – Refers to a series of lines of data that are made sequentially, writing each line so it follows the previous. It also refers to the series of scanning lines that form the image on a computer video display, as well as the manner in which a scanner scans original copy and exposes the film line by line.

Raster Image Processor – Device that translates page description commands into bitmapped information for an output device such as a laser printer or image setter.

Rasterization – The process of converting mathematical and digital information into a series of dots for conversion into printing images.

Ratio – An output feature on a tension controller that multiplies (for unwind applications) or divides (for rewind applications) the sampled control output by a factor adjustable between 1 and 10. The ratio feature allows an instantaneous change in control output to correspond to the roll diameter change that takes place during a flying splice.

Rayon – A man-made fibre created from the cellulose found in plants and trees and processed with harsh chemicals that release hazardous air pollution. Any plant or tree – including bamboo – could be used as the cellulose source, but the fibre that is created is rayon.

RC Paper – Resin-coated photographic paper used in phototypesetters for image output.

RDZ thermal transfer ribbon – A ribbon designed by QuickLabel Systems for anti-counterfeiting label printing applications, in which the authenticity of a product must be verified on a production line or in a distribution centre. RDZ thermal transfer ribbon for security-labelling applications produces printed text, barcodes, and other label content that is only visible under ultraviolet light. When exposed to UV light, print produced by QuickLabel’s RDZ ribbon appears to be a neon-bright fluorescent green or yellow, depending on the substrate. A covert barcode or other security label marking printed using RDZ security ribbon is said to be easily read by a UV barcode scanner, and is also visible to the human eye in the presence of illumination from a UV light source such as a black light. RDZ ribbon is said to look like a standard roll of thermal transfer ribbon, and can be installed on a standard thermal transfer barcode printer in the usual way. The ribbon is said to be compatible with synthetic label stocks, including polypropylenes, polyesters, and some coated paper label materials.

REACH – A new European Community Regulation on chemicals and their safe use (EC 1907/2006). It deals with the Registration, Evaluation, Authorization and Restriction of Chemical substances. The new law entered into force on June 1, 2007. The aim of REACH is to improve the protection of human health and the environment through the better and earlier identification of the intrinsic properties of chemical substances. (http://ec.europa.eu/environment/chemicals/reach/reach_intro.htm)

Ready-to-eat products

Ready-to-prepare refrigerated products


Realhardwood paper

Ream – Unit consisting of 500 identical sheets of paper (usually). In some parts of the world reams contain 480 sheets.

Reaming – A method used to trim and size plastic bottle finished. A special rotating cutting tool trims the sealing surface smooth and simultaneously reams (bores) the bottle opening to desired size.

Recloseable bags

Recloseable alu-can

Recovered paper – Paper and paper by-products that have been separated, removed or diverted from solid waste disposal and are intended for sale, use, reuse or recycling, whether or not such paper requires subsequent separation and processing. Does not include tissue or paper recycled internally by the paper industry.

Recovery rate – Volume of paper recovered as a percentage of volume of paper consumed.

Rectification – Conversion of alternating to direct current.

Recyclable – Includes the reuse, reconditioning, and remanufacturing of products or parts in another product.  (http://www.ftc.gov/opa/1998/04/green.shtm)

Recyclable packaging – A piece of packaging that can be recovered and returned for either its original purpose or for another purpose.

Recycled Content – Refers to the percentage of recycled materials in a product. “Recycled content” includes products and packages that contain reused, reconditioned or remanufactured materials, as well as recycled raw material. (http://www.ftc.gov/opa/1998/04/green.shtm)

Recycled fibre pulp – Pulp produced from recovered paper; contains only recycled fibres and is used in papermaking. Recycled fibre pulp can be used either de-inked or not-de-inked.

Recycled Fibres (aka Recovered Fibres, Secondary Fibres) – Fibres recovered from wastepaper, printing and converting waste, and forest and lumber mill residues to be used for the manufacture of paper or paperboard.

Recycled Material (Fibre) – Reclaimed material which, after repulping, is used as one of the two principal furnishes for paper or paperboard. This includes boxboard cuttings, over-issue newspaper, reclaimed corrugated containers, mixed paper, tabulating cards, envelope cuttings, kraft cuttings, etc.

Recycled paperboard

Recycled pulp – Collections of waste paper and board, generally from selected sources and of known quality.

Recycling – The reprocessing of old materials into new products, with the aims of preventing the waste of potentially useful materials, reducing the consumption of fresh raw materials, reducing energy usage, reducing air (from incineration) and water (from landfill) pollution by reducing the need for “conventional” waste disposal, and lowering greenhouse gas emissions as compared to virgin production. Recycling is a key concept of modern waste management and is the third component of the “Reduce, Reuse, Recycle” waste hierarchy, though colloquial usage of “recycling” can also include “reuse.” (http://en.wikipedia.org/wiki/Recyclable)

Recycling Codes for Plastics – source: http://www.PlasticFreeBottles.com


Recycling stream

Reducers – Materials used to reduce the strength of an ink. May be an extender or white or varnish.

Reducing Agent – A compound that causes chemical reduction, thereby itself becoming oxidized.

Reduction – A chemical reaction that adds electrons to a reactant, usually through the addition of hydrogen or the extraction of oxygen. Such a reaction occurs at the cathode in a plating tank.

Reel Stand – Device at the unwind section of the press that holds the reel (roll) of substrate to be printed. Also called the unwind stand.

Refillable packaging – A piece of packaging that is returned back to the system to be refilled after being cleaned and restored.

Refiner – A machine in which wood chips are broken down into fibres.
Refiner mechanical pulp (RMP) – Mechanical pulp produced by passing wood chips between the plates of a refiner.

Reflectance – The ratio of the intensity of reflected radiant flux to that of incident flux. In popular usage, it is considered the ratio of the intensity of reflected radiant energy to that reflected from a defined reference standard.

Reflective Densitometer – Instrument used to measure the density on paper. Operates by measuring the amount of light reflected.

Reflective Object – A solid object that returns some or all of the wavelengths of light that strike its surface. A reflective object that returns 100% of all light is called a perfect diffuser or a perfectly white surface.

Reflectivity – Ability of paper or board to reflect light; a measure of gloss
Refractive Foil Stamping – Process that gives an etched, old-world feel to a flat foil stamp through engraved cross-hatched lines that add texture and dimension. This technique also serves to emphasize the spectral reflections of colour inherent in metallic foils.

Rexam regal_closureRegal closure – Linerless tamper-evident closure ideal for carbonated soft drinks.

Registration – (or Register) Accuracy of imposition to secure correct alignment of the printed colour-to-colour areas of a multi-colour design image and of the design-to-scores shown on a die sheet. Also, the correct placement of the design on the printed areas or items. Colour-to-colour is usually referred to as “printing register.” Design-to-scoring is called “cutting register.” When the inks appear to overlap improperly or leave a white gap on the page, the printing is considered “out of registration” or “poorly registered”.

Registration Marks (bull’s-eyes) – Small cross-hair lines printed in the margins of webs and press sheets that serve as guides for the precise alignment of subsequent image overprints.

Regrind – Ground plastic usually made from scrap from a plastic operation. It is usually blended with virgin material and remoulded.

Regular Number – The quantity of boxboard sheets, 25” x 40” (1,000 square inches) required to make a bundle of 50 pounds.

Regular Slotted Carton See: RSC

Reinforcement – Method for strengthening paper with an insert or surface layer of glass or other synthetic fibre or metal.

Reinforcement pulp – Softwood chemical pulp added to give paper greater strength and to improve runnability on the paper machine or printing press.

Reject – Material removed and discarded during the cleaning of pulp/stock.

Relative density – Mass of a unit volume of a particular substance.

Relative Humidity – The percentage of water vapour in the air compared to the total amount possible at the same temperature.

Release coating – A coating applied to the non-sealing side of cold-sealable packaging films and laminates supplied in a roll form that will allow the packer to unwind these films or laminates on packaging machines.

Release paper – Backing paper for self-adhesives.

Relief Printing – Printing method whose image carriers are surfaces with two levels having inked areas higher than non-inked areas. Relief printing includes block printing, flexography and letter press.

Relieved area – An area, outside the product containment zone, that is designated to remain not sealed; this is to facilitate ease of opening.

Rendering Intent – The method a CMM uses for converting (i.e., mapping) colours from one device’s gamut to another. The four methods are Perceptual, Saturation, Relative Colorimetric, and Absolute Colorimetric.

Renewable Resource – A natural resource qualifies as a renewable resource if it is replenished by natural processes at a rate comparable or faster than its rate of consumption by humans or other users. Resources such as solar radiation, tides, and winds are perpetual resources that are in no danger of being used in excess of their long-term availability. Natural resources that qualify as renewable resources include oxygen, fresh water, timber, and biomass. However they can become non-renewable resources if used at a rate greater than the regeneration of new materials. (http://en.wikipedia.org/wiki/Renewable_resource)

Repeat Length – The completed image or application of one image carrier revolution ( Usually the same as the cylinder circumference).

Repeatability – Ability of a device, such as an image setter, to produce film or plates that yield images in register.

Resample – To change the resolution of an image. Re-sampling down discards pixel information in an image; re-sampling up adds pixel information through interpolation.

Re-screening Colour Separations – In lithography, the ability to make a colour separation from an original that has already been separated and published. There are limitations. Since the same basic screens and screen angles are used, it is necessary to slightly enlarge (104% or greater) or reduce (90% or smaller) in order to reduce or eliminate conflicting screen angles causing a moiré pattern. The further use of a sharp or unsharp masking controls and the use of selective focus may also be necessary.

Resealable packaging

Resealable zipper

Resin – An organic substance of natural or synthetic origin characterized by being polymeric in structure and predominantly amorphous. Most resins, though not all, are of high molecular weight and consist of long chain or network molecular structure. Usually resins are more soluble in their lower molecular weight forms.

Resist – (1.) Material which resists the action of a plating solution. (2.) Materials applied to part of a cathode or plating rack to render it nonconductive.

Resize – To change the size of an image while maintaining its resolution.

Resolution – (1.) The level of quality at which graphics are printed. The higher the resolution, the better the quality of the printed graphics. (2.) Measure of image output capability, usually expressed in dots per inch (dpi). (3.) Measure of halftone quality, usually expressed in lines-per-inch (lpi).

Resource Conservation and Recovery Act (RCRA) – The public law that creates the framework for the proper management of hazardous and non-hazardous solid waste. The Office of Solid Waste (OSW) is the regulatory body.  http://www.epa.gov/epaoswer/osw/laws-reg.htm


Retention – Proportion of fibre and filler retained on the paper machine wire.

Retention Factors – The October 2006 Control Techniques Guideline (CTG) for Letterpress and Lithographic Printing recommends that state and/or local pollution control agencies use substrate “retention factors” in the calculation of VOC emissions lithographic and letterpress printing facilities. Retention factors assume that a percentage (i.e. 20% for heatset and 95% for coldset inks) of the ink VOC content remains in the substrate and is not emitted.

Retort – The process of cooking food in a pressurized vessel for purposes of sterilizing the contents. Generally retorting is in the package it is sold in e.g. baby food or soups that have meat or vegetables that need to cook at a temperature to kill off the micro-organisms and avoid botulism. The temperature is generally around 121°C.

Retort Applications (flexible packaging) – One of the fastest growing applications for flexible packaging is retort, named for the cooking process in which the pouch, filled with the food product, is heated to 125°C. The consumer then reheats the food in the single or multiple serving pouches in which it is packaged. The Japanese, Europeans, and the US military long have known this method of food preparation not only is more convenient than heating in separate containers but also results in tastier food because of less overcooking near the outside of the container and superior moisture retention. Common retort structures involve combinations of OPET and OPA substrates along with an FDA-compliant functional barrier layer. Retorting, however, is a very aggressive thermal process. As a result, OPP normally is unsuitable for such applications, although cast PP often is used for the inner sealant web. Recent developments in retort films include clear barrier vacuum deposition for OPET substrates, OPET materials with excellent adhesion on both sides, high-elongation OPET to provide superior puncture resistance, and metallized PET (MPET) with retortable adhesion-promoting layers to improve the bond between the metal and the base sheet.

Retort bottle

Retort pouch

Retortable carton


Retouching Colour – The correction or deliberate manipulation of colour, tone or detail in an original work of art, photograph or other original which needs correction. Note: retouching materials, especially in photography, must be specifically designed for use on photographic materials such as prints or transparencies. Often when incompatible materials are used, it becomes difficult if not impossible to reproduce a similar or exact colour.

Reusable Retail Package (RRP) – AVC designed and patented the RRP with the idea that consumers need a better package for products with multiple components. The idea was to make the package become part of the product by making the package itself a reusable storage device to house and maintain the product(s) and accessories indefinitely. Over the years, AVC has expanded on this concept. We now offer multiple versions of the RRP. The two main versions are one with plastic outside and one with blister board outside. This package is environmentally friendly because it is reusable and also because it can be made using PVC alternatives. The RRP can be made in any size or shape. It is a great marketing tool as the product sits on the consumer’s shelf, displaying your company name and logo for the life of the package.

Revalidation – Documented procedure to reconfirm an established validation (ref. ISO 11607 – 2003(E)).

Reverse – Type, graphic or illustration reproduced by printing ink around its outline, thus allowing the underlying colour or paper to show through and form the image. The image “reverses out” of the ink colour. Also called knockout and lift-out.

Reverse Plate – A plate on which the reproduction of an original design is produced in negative form.

Reverse Printing – When clear film labels are printed on the back side, referred to as subsurface printing, with a reverse image. When the label is applied to the product, the printed image will be between the container and the label stock which protects it from scuffing. After the label is applied, the reverse printed image will be right reading. While not mandatory in all industries, it is the preferred method for the food industry as it guarantees there will be no ink contact with the food product.

Reverse Printing Unit – A printing deck on a gravure press that reverses the web path without turning it, allowing the back (reverse) of the substrate to be printed.

Reverse tuck in end carton – Carton where the end tuck flaps are extensions of the opposite carton faces.

Reversible addition-fragmentation chain transfer technology – A form of controlled free radical polymerisation which enables the synthesis of tailored polymers, whose applications include novel pigment dispersants for inkjet printing on packaging. One of the attractions is that RAFT technology allows for complete control over the size and shape of molecules. In February 2010, Belgium-based Agfa submitted a patent application for an inkjet printing method based on RAFT that is capable of handling a variety of different types of packaging. This uses an inkjet printer without compromising the consistency of image quality, physical properties, such as adhesion of the image to the substrate, and productivity. RAFT enables drying of the inks to be replaced by polymerisation, using ultraviolet radiation in the wavelength range of 100 to 400 nanometers.

Revolve mechanism

Rewind Zone – A tension zone, typically on converting machinery, created between a driven nip roll or other tensioning point and the driven core onto which the web is wound.

Rewinder – A machine that takes rolls from the winder, slits or rewinds into smaller rolls.

Rewinding – The process of winding the paper from the reel onto a core to produce rolls of the desired width, diameter and tension for the customer, to splice the ends together, and/or to remove defects.


Rex-The Talking Bottle

RFID – Radio-frequency identification (RFID) is an automatic identification method, relying on storing and remotely retrieving data using devices called RFID tags or transponders. The current thrust in RFID use is in supply chain management for large enterprises. RFID increases the speed and accuracy with which inventory can be tracked and managed.

RFID tag

RGB (Red, Green, and Blue) – The additive primaries red, green, and blue. The colours used by computer monitors. The combination and intensities of these three colours represent the whole spectrum.

Rheology – The study of flow and deformation of matter.

Ribbon – The slit portions of the full web on a publication press. The web is slit into ribbons before the paper enters the next section of the folder for processing.

Right Reading – Copy that reads correctly in the language in which it is written. Also describes a photo whose orientation looks like the original scene, as compared to a flopped image.

Rigid Paperboard Can (dry products) –

Rigid Plastic Packaging – Freestanding plastic bottles and plastic fittings. The main raw materials used are PET, HDPE and PP.
Roll – Paper or board wound around a core or shaft to form a continuous roll or web. Rolls are made by slitting and rewinding a paper machine reel and are available in many widths and diameters.

Ring-pull easy can opening see Stay-on Tab and Ring-pull Tab.

Ring-Pull Tab – The ring-pull tab is the predecessor of the well-known stay-on tab and has been around since the late 1970s as a fixture of cans in the beverage industry. It was used as a solution to the dilemma of how to open a beverage can without a can opener. The ring-pull was first seen in the latter half of 1962, when Alcoa supplied it to the Pittsburgh Brewing Co. for its Iron City brew (see Modern Packaging, Nov., ’62, p. 105). The design consisted of an aluminium tab that was integrally riveted to the can’s aluminium lid. Consumers would pull up and outward on the ring to remove the tab, revealing a keyhole-shaped opening large enough to permit simultaneous air intake and pouring. However, its drawbacks, including cut fingers and disposed tabs on beaches and on the ground in picnic areas, eventually led to the development of the stay-on tab. Reynolds Metals Co. began supplying the stay-on to Coca-Cola in 1976 (see Packaging Digest, Jan., ’76, p. 54). While the stay-on tab has been the mainstay in beverage packaging since, the ring-pull has found new avenues of use. It is often used today for applications such as canned fruit, bean sprouts and soups, as well as many on-the-go packages, where the ring-pull is used to remove the entire can top. (see also Stay-On Tab)

RIP (Raster Image Processor) – The hardware/software which converts data which has been stored in a computer into a series of lines of tiny dots which are output on film or photographic paper. In line work, the dots can be grouped to create solid areas.

Ripple – Regular modulations in the direct current output wave of a rectifier unit, or a motor generator set.

Robber – An auxiliary cathode placed to divert to itself some current from portions of the work which would otherwise receive too high a current density and excess plating deposition. See also – Thief.

Rochelle Salt – Sodium potassium tartrate KNaC4H4O6-4H2O.

Roll – A web in wound roll form. This term is also used in the converting industry for rollers.

Roller – A rotating cylinder used for web transport. Aliases include idler rolls, idler rollers, drums, rolls, pipe rollers.

Roll-on – A capping system which secures the closure onto the bottle by means of rollers that bend a component of the closure under a bead of the bottle.


Roll-Out – Ink spread for testing or sampling purposes by using a hand-roller.

ROPP – roll-on pilfer-proof screw cap.

Rosette Pattern – A screen dot pattern that is formed by printing two or more halftone screens over one another and which have a 30ø or more angle difference between them. Example: a 45-degree, a 75-degree and a 105-degree combination would yield a good three-color rosette pattern without an objectionable pattern. When a screen with less than a 30-degree angle is included, an objectionable pattern develops and can be seen (unless it is used in the yellow printer) this is called a moiré pattern.

Rosin – A specific resin that is obtained from pine trees.

Rotary Die – The die used in the rotary die-cutting process.
Rotary Die-cutting – Cutting and creasing by means of accurate metal dies mounted on a backup cylinder so as to permit continuous cutting and scoring of a paperboard sheet.

Rotary Press – Printing press that passes the substrate between two rotating cylinders when making an impression.

Rotogravure – (1) An intaglio printing process using cylinders on which an image is etched in the form of a series of cells. These cells are filled with ink and the excess removed by means of a doctor blade. Ink from the wells is transferred by the rotary action of the press to the board in either sheet or web form. (See “Gravure”). (2) A printing process in which letters and pictures are transferred from an etched copper cylinder to a web of paper, plastic or similar material in a rotary press.

Roto News – Any of five grades of uncoated groundwood manufactured expressly for gravure printing.

Rotogravure Press – An unwind or feed section, a series of one or more workstations, one or more of which is a rotogravure print station, any dryers associated with the work stations, and a rewind, stack, or collection section. Inboard and outboard workstations including those employing any other technology, such as flexography, are included if they are capable of printing or coating on the same substrate.

Rotogravure Printing – An intaglio process of rotary printing from tiny etched cells in a copper covered roller surface. Often overchromed for longer wear. Does fine printing, along with half-tones and gradation of tone. Uses solvent type, fast drying inks. Also known as Gravure Printing.


RSC – This is the abbreviation for Regular Slotted Case, the most commonly used style of carton. One side is glued, taped or stapled during manufacturing, making this carton well suited for easy set-up, filling, and closure. In Europe also known as American Box/Case.

RTD – Ready-to-drink.

RTE – ready-to-eat.

Rub – An ink that has not reached maximum dryness and does mar with normal abrasion.

Rule – Line used as a graphic element to separate or organize copy.

Rule 41 – Rule 41 of the Uniform Freight Classification specifies standards for certifying the strength of corrugated cartons. These standards are based on minimum bursting strength requirements for standard basis weights of linerboard used. See Alternate Rule 41.

Runnability – (1.) The physical ability of a roll of paper or substrate to pass through a press under prevailing conditions of tension and speed without web breaks. Distinguished from Printability. Also how well cartons run on an automatic packaging line. (2.) The paper properties that affect the ability of the paper to run on the press. These properties also affect how the inks make contact to the paper, the rate of the absorbency, the trap and the holdout of the ink on paper combination.

Running In – The process of seating a doctor blade to a cylinder. Also called “toning in.”

0 – 9