Countries / Territories

Packaging - Glossary - R

  • Packaging Processes

      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  

    The Glossary of the International Trade Centre (ITC) on the technical terms used in the packaging sector is a database designed to provide updated information on the specific terminology used in the packaging industry. This Glossary is a tool placed at the disposal of users for information only. It is not designed to replace the appropriate professional advice in any way. Users are invited to submit their comments and observations by email to Mr. Frederic Couty, Senior Adviser, Export Packaging at the following email address: fcouty[at]intracen.org

    Select an alphabetic above to access the glossary.

  • R


    In warehousing, metal or wooden shelves for storing of merchandise, usually unit loads on pallets. In retailing, a pegboard or similar system for display or self-service packages or e.g. specially shaped racks for spices, bottles or sachets.

    Radio frequency identification device (RFID)

    Microchip encased in plastic that is attached to packages and other articles for identification and tracing purposes.


    A small tapered indent in the base of a container by means of which it can be located and correctly oriented for accurate printing or label placement.


    A unit of quantitative measure used in the marketing of paper (500 sheets).


    Packaging materials or packages that may be reprocessed into raw materials for subsequent re-conversion into packages or for secondary purposes.


    1.   The untrimmed roll of paper that is wound on the full-width shaft at the paper machine dry end. Also used for other materials (plastic film, tapes, etc.) wound onto a core.

    2.   The shaft on which the paper is first wound when it leaves the dryer.

    3.   Any core or shaft onto which material is wound.


    Container shape having internal dimensions larger than its aperture and therefore only achievable by blow-moulding or more complex technology (collapsing cores for moulds, etc.).


    In multicolour printing, the extent to which each colour is laid in the correct position relative to the others and to the dimensions of the material on which it is printed.

    Register mark

    A mark or symbol used throughout printing production to assist in achieving correct alignment (register) of images and colours; typically appears as two perpendicular lines in crossed form centred in a circle or oval.


    In labeling and over-wrapping operations, the placing of the print/design in correct orientation relative to the pack faces, especially in the case of irregular-shaped containers. The container is rotated and a small protrusion (called a registration or spotting lug) or depression (called a concealed or dimpled lug)near the base, stops the rotation when registration is correct.


    Ground plastic made out of scrap from a plastic conversion operation. It can usually be blended with virgin material and remoulded.

    Regular slotted container (RSC)

    The most widely used type of corrugated or solid fibreboard box used as transport package. Designated in the International Fibreboard Case Code as box style No. 0201.

    Reinforced plastic

    A plastic whose strength properties have been increased by the addition of high-strength fibres such as fibreglass imbedded in the material.

    Relative humidity (RH)

    The ratio of actual humidity to the maximum humidity (weight of water vapour) which can be retained in an air sample without precipitation at a given temperature and pressure.

    Release paper

    Mainly silicone-coated glassine or kraft paper whose purpose is to serve as a backing and support for adhesive-coated materials. The silicone coating prevents the adhesive from sticking to the release paper.

    Removal torque

    The turning or twisting force re­quired to remove a lug cap, screw cap, or twist-off crown. Usually measured by means of atorque meter.


    Material that can be renewed/replaced, such as wood, and for which production is therefore sustainable over the long term.

    Repeat motif printing

    A continuous repetition of a printed design on a packaging material or label, so as to eliminate the need for registration of the print with the package dimensions on the packing machine (also called repeat design).


    Shipping container in which empty unit containers are received and intended to be used as shipping containers for the product pack­aged in the unit containers.


    Any of a class of solid or semi-solid organic products of natural or synthetic origin, general­ly non-crystalline and of high molecular weight with no definite melting point. Resins are gen­erally water-insoluble and have little or no tendency to crystallize. However, certain resins used in packaging, such as polyvinyl alcohols and polyacrylates, are readily dispersible in water, and others, such as polyamides and polyvinylidene chloride are readily crystallised.

    Retail package

    A package suitable for retail distribution of consumer units of a product.


    A large, pressurised container used for heat sterilization of packaged foodstuffs. In a balanced pressure retort, the pressure within the retort is kept in balance with that inside the heated containers, to minimize the internal/external pressure differences and resultant stresses on the container walls.

    Retort pouch

    A flexible pouch, usually made with aluminium foil laminates, filled with a food product and designed to withstand the temperature and pressures of processing in a pressure-balanced retort.

    Returnable package

    A container designed for return to the filler of the product it contains, to be refilled with the same product. See also: Deposit.

    Reusable package

    A container which, when emptied, can be used to package either the same or different products.

    Reverse printing

    Printing on the inside surface of a transparent film so that the printing is visible in reversed form when it is viewed from the outside. Results in a high-gloss print appearance and protection of the ink from scuffing and abrasion.

    Reverse Taper Closure

    A closure silhouette characterized by the top of the closure being larger in diameter than the open end.

    Reversible pallet

    A pallet that can be used with either of its faces upwards.


    To wind again; especially the winding of a roll of paper, film or other flexible packaging material after printing, slitting, etc. To transfer to other rolls, usually smaller, after slitting, etc.

    Re-worked material (thermoplastic)

    A plastic material that has been reprocessed, after having been previously processed by molding, extru­sion, etc., in a converter’s plant. Use of re-worked material in packaging applications is normally limited to clean plastic that has been generated from the converter's own production, meets the requirements specified for the virgin material, and yields a product of essentially the same quality as one made only from virgin material.

    Rigid package

    A non-collapsible non-flexible package that has a fixed shape and retains that form whether full or empty.


    A defective container characterized by an uneven or bulging bottom that permits rocking.

    Rockwell Hardness Test

    A test for determining hardness of steel and tinplate, used as a guide in determin­ing plate temper and suitability for metal packaging applications.


    Glass and polyethylene rods are used particularly in the drug and cosmetic industries. One of the most common is a balled-end rod for touch applying medicines.


    A quantity of material supplied in web form, such as paper, film, or aluminium foil when wound into cylindrical form on a shaft or core.

    Roll–on-pilfer-proof (ROPP) cap

    Metal closure for glass and rigid plastic bottles. A plain metal shell, normally aluminium, is placed over the threaded finish of the bottle and its skirt is pressed against the threads byrollers that press the metalto make it conform to the thread shape. Threads are thus formed on the shell so that it becomes a screw cap. A continous, breakable ring can also be formed at the rim of the cap, to provide a tamper-evident (not in fact pilfer proof- PP)  feature.


    Gravure printing with a thin, quick-drying ink from a cylindrical etched roller (see gravure).

    Rubberized hair

    A cushioning material produced by bonding curled animal hairs with latex rubber which is then vulcanized and cut into sheets.

    Rubber printing plate (stereo)

    A hard rubber sheet into which the reverse of the design to be printed is impressed by etching or sculpting techniques. Variants of this plate are used in flexographic and in dry offset printing.

    Run Length

    Number of packs to be producd or filled during a productionrun before change over to a different pack/product configuration; number of copies to be printed during a print run.


    An enclosed channel taking molten plastic from the extruder to an injection mould. For multi-cavity moulds, the multiple runners required may be heatedto keep the plastic fluid and are referred to as ‘hot runners’.

    Rust inhibitor

    A chemical agent contained in a coating material which is applied to metal surfaces to prevent or reduce rusting. See also: Corrosion.

  • Upcoming events

    • Loading...