Updated 02 Jan. 2010
OBA – See: Optical Brightening Agent.
OBPA – Oxo-Biodegradable Plastics Association. The oxo-biodegradation industry claims its plastics “self-destruct” or biodegrade when they are exposed to UV irradiation or heat because substances such as cobalt, nickel and zinc are added to conventional plastics at the time of manufacture. These reduce the molecular weight of the material over a pre-determined period and they fragment – allowing them to be consumed by bacteria and fungi.
But the industry association European Bioplastics (EB) challenges these claims because it says at present they cannot be verified with reference to international standards. The organisation said OB products did not biodegrade but only fragment into invisible pieces, saying “this is not generally considered as a feasible manner of solving the problem of plastic waste”.
But the Oxo-Biodegradable Plastics Association (OBPA) dismissed EB arguments saying its products were tested for degradability, biodegradability and non-eco toxicity against criteria laid down in American Standard ASTM D6954-04. Authorities in France had published a standard for OB products, while the UK was in the process of developing one, it added.
OCR paper – Optical character recognition paper. A wood-free paper suitable for optical scanning or reading.
Off-machine coating – Coating of paper on a separate coating machine
Off-machine creping – A method whereby paper is creped in a separate operation rather than by the paper machine’s Yankee cylinder.
Offset – (a.k.a Lithography) An indirect printing method in which the inked image on a press plate is first transferred to a rubber blanker that in turn “offsets” the inked impression to a press sheet. In offset lithography, the printing plate has been photo-chemically treated to produce image areas and nonimage areas receptive to ink and water, respectively. Offset print provides the highest degree of precision, clarity, and quality. There are both webfed and sheetfed offset presses.
Offset Lithography – The lithographic printing process by which a photographically made ink receptive image on flexible metal plates is transferred by means of a rubber blanket to boxboard or the material being printed.
Offset Powder – A powder applied to the surface of a litho-printed sheet to prevent the ink from transferring (offsetting) to the surface of the adjacent sheet as the sheets are stacked off the delivery end of the printing press.
Offset/Lithographic Printing – This printing medium is the transfer of ink from a sensitised plate, offset to a rubber blanket then transferred to the substrate. The equipment is a multi-station (up to eight) printing machine to print and/or coat up to six colours on to sheets or a fast-moving web.
O-I Glass –
One (single-face) – or two sheets (double-face) of linerboard are attached to create the structure. A double-face corrugated container is referred to as a single-wall container. Corrugated is primarily used for shipping containers. The height of the fluted medium varies and is referred to by a letter. Common flute sizes are A, B, C, E, F, G and N.
One-trip – Pack or container designed for single use only.
On-machine coating – Coating of paper on the paper machine (also inline term is used).
Opacity – (1) Opacity expresses the degree of non-transparency. High opacity is essential when a paper is intended for duplex printing, or for intensive colour printing on one side of the sheet. Greatly influenced by basis weight, brightness, type of fibre, and type of filler. (2) Hiding power of pigmented (mostly white) plastic films. It is beneficial for packing materials sensitive to light (visible or ultraviolet).
Opaque – Descriptive of a material or substance which will not transmit light. Opposite of transparent q.v. Materials which are neither opaque nor transparent are sometimes described as semi-opaque, but are more properly classified as translucent, q.v.
OPET-film – Oriented polyethylene terephthalate (OPET) film.
OPP – Oriented PP (polypropylene) film. A stiff, high clarity film, but not heat-sealable. Usually combined with other films, (such as LDPE) for heat-sealability. Can be coated with PVDC (polyvinylidene chloride), or metallized for much improved barrier properties. Used as a substitute for PET due to a more competitive pricing and the ability of the material to have a matte finish. Laminates made using this outer substrate tend to wrinkle easier when heat sealed.
OPS Shrink Film – Oriented Polystyrene film. Very common alternative to PVC shrink films in Asia and Europe, but not readily available in the USA. Slightly higher priced than PVC films but more recyclable and has a greater shrink percentage.
Optical Brightening Agent (OBA) – A colourless fluorescent dye that absorbs invisible UV (ultraviolet) light and converts it to visible light falling into the blue to violet portion of the spectrum, which is then reflected back to the viewer’s eyes. The result is high-bright blue-white paper.
Optical characteristics – Characteristics of the appearance of paper or board. Most important are colour, brightness, opacity and gloss.
Optical Filters – Additives which selectively absorb, reflect, or transmit a certain area of the solar energy spectrum, thus enabling manipulation of that radiation in a desired way.
Optically Stable – Resistant to yellowing.
Opti-Wave – An ultra-lightweight medium designed specifically for the rapidly growing mini-flute market.
Organic Food –
Orientation – The alignment of the crystalline structure in polymeric materials so as to produce a highly uniform structure. Can be accomplished by a cold drawing or stretching during fabrication.
Orifice – (1) Generally, any opening. (2) The opening in the neck which the contents of the tube are normally dispensed. Orifice may be round, oval, ribbon, square, etc.
Orion closure – This closure is designed for capping carbonated soft drinks (4.2V) and mineral water. Suitable for PCO and BPFC PET bottles. Features an outside deformable seal.
OS Film – Oxygen-scavenging polymer layer. In 1999, Cryovac introduced a new oxygen scavenger film, OS1000, said to be the world’s first polymer-based oxygen scavenging system, which eliminated residual oxygen from packages packed under low-oxygen, modified-atmosphere conditions. The new technology, for use with processed or dried meat products, not only gave processors an alternative to putting oxygen-scavenging packets into their products, but it also provided an entirely new way of using films to rid packages of residual oxygen, which can lead to discolouration, off-flavours and even mould in meats. The OS1000 packaging system, consisting of a barrier foam tray fitted with a unique peelable barrier film lid, gave processors up to 18 days to move packages of case-ready fresh ground beef to the retailer in a low-oxygen environment. At the supermarket, retailers then peeled off the barrier portion of the film serving as an oxygen barrier, allowing oxygen to enter and the meat to regain its full red colour in what is called a “blooming” process. With the barrier layer removed, leaving a thinner permeable film layer, the beef could retain its colour for 48 hours – about double the time a typical store-pack of beef could retain colour at that time.
OTC paper – One-time carbonizing paper. Carbon paper that produces one copy only. Used, for example, for receipts.
OTG – On-The-Go.
OTR – Oxygen transmission rate. OTR of plastic materials varies considerably with humidity, therefore it needs to be specified. Standard conditions of testing are 0, 60 or 100% relative humidity. Units are cc./100 square inches/24 hours, (or cc/square meter/24 Hrs.) (cc = cubic centimetres)
Outlast Thermocules –
Out-Of-Stocks (OOS) –
Overcap – A cap (usually plastic) provided with some cans. It is used to cover the open end once the can has been opened. Sometimes, it is used to describe a cap that is used to cover the primary closure or other dispensing system, such as a fingertip sprayer or aerosol valve.
Overflow Capacity – The capacity of a container to the top of the finish or to the point overflow.
Overlay – A low basis weight, < 30 lbs/3000 ft2 (18 gsm), low opacity paper, treated with melamine resin that provides protection for printed designs. Also used in a broader sense to describe foils and impregnated decorative papers.
Overprint – To print additional material, such as a varnish or another colour, on a previously printed sheet.
Overwrap – A plain or printed sheet of paper, foil or flexible film applied over a filled carton or tray for decorative or protective purposes. Technically it is defined as the type of wrap that provides a tuck and fold on the ends of a package, as different from shrink wrap or flow wrap.
Owens-Illinois – see O-I.
Oxo-Biodegradable Plastics Association – see OBPA
Oxygen bleaching – A process in which pulp is initially treated with oxygen followed by 4-5 bleaching stages.
Oxygen transmission rate – OTR of plastic materials varies considerably with humidity, therefore it needs to be specified. Standard conditions of testing are 0, 60 or 100% relative humidity. Units are cc./100 square inches/24 hours, (or cc/square meter/24 Hrs.).
Oxygen-Scavenging Technology –
Oxygen-Sensitive Substance –
Ozone bleaching – Pulp can be treated with ozone at the start of the bleaching sequence to lower its lignin content. Ozone allows bleaching to high brightness without chlorine chemicals.