Like most industries, the envelope industry has its own technical terms or jargon.
The following list summarises many of the terms and definitions used;
Envelope Dictionary
B 9 wordsTOP
Bangtail
A special type of wallet incorporating a perforated flap and an extension from the throat e.g. a Barclaycard envelope.
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Banker
An envelope with a diamond shape or V-flap opening on the long edge, also known as invitation envelopes.
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Basketweave
A manilla paper with a weave effect finish, traditionally used for heavy weight papers, typically in 115gsm.
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Bespoke
Customised envelopes made to customer specifications, not from stock.
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Biobased
Biobased products are comprised of completely renewable resources, and can be either biodegradable or non-biodegradable.
Biomass
A source of fuel made from living or recently dead plant materials, such as: wood, leaves, and biodegradable parts of industrial and municipal waste. Also considered a carbon neutral energy source.
Blank Fed
Envelopes manufactured from flat sheets, punched out and made up.
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Board Back
An envelope style that is generally a pocket, made with a cardboard back & paper front. Typically, 120gsm paper and 1000 micron board is used.
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BRE
Short for Business Reply Envelope, these are pre-printed with the sender’s return address and a prepaid postage. Also known as ‘prepaid envelopes’.
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C 7 wordsTOP
Carbon Emissions
Relating to climate change, carbon dioxide released when substances such as: oil, gas, and coal are burned by vehicles, factories, and homes.
Carbon Offsetting
Schemes that allow investment in environmental projects around the world that balance out or compensate for carbon emissions.
Card Envelope
A protective envelope made completely from card. Sometimes this may also refer to an envelope that is used to send a greetings card in, such as our Invitation envelopes.
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Climate Neutral
The amount of Carbon Dioxide released is balanced with an equivalent amount of carbon removal. E.g restoring forests.
Colour Wash
A printing technique used to give a tinted or coloured effect. This often relates to internal opaques.
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Compostable
Composting is the process in which organic waste is broken down by microbial digestion to create compost.
Corn Starch Window Film
Normal window films will not biodegrade, however corn starch window film biodegrades in 30 days.
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D 3 wordsTOP
Deforestation
Deforestation is the removal of a forest from land which is then to be converted for non-forest use – often involving forest land being used for farming or urbanisation.
Diamond Press Envelopes
A make of envelope printing press, good for larger envelope sizes such as C3, as well as board backs and gussets.
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Drilled Holes
Small holes which are typically drilled into internal mail transit pockets, used to check for inserts.
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F 2 wordsTOP
Flexo
A printing technique carried out during manufacture or printing in-line for large quantities which are not up to the quality of litho printing.
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Fossil Fuel
A non-renewable resource formed over millions of years. The burning of fossil fuels is the largest source of emissions of carbon dioxide and directly contributes to global warming.
G 5 wordsTOP
Glassine
A paper based material used for envelope windows and some wage and photographic pockets.
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Greenhouse Gas Emissions
Emissions of gas which contribute to global warming by absorbing infrared radiation, thereby heating the atmosphere. Main contributors are carbon dioxide, methane, and nitrous oxide.
GSM / Grammage
A measurement which determines the weight of paper, measured in g/m2.
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Gummed
This refers to the envelope sealing method that requires moistening to seal. This is the most common type of sealing.
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Gusset
An envelope with an expandable side seam, these can have a block bottom or V- bottom.
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H 2 wordsTOP
Halm Jet Press
A make of envelope printing press most commonly used in the envelope industry.
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Hot Melt
A form of Peel & Seal adhesive, holt melt is a narrow band of adhesive similar to double sided tape with a heavier gram weight than normal.
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I 1 wordsTOP
Invitation Envelopes
A gummed envelope with a classic diamond flap, usually used for greetings cards and invitations.
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L 1 wordsTOP
Laser Window Films
A window film of double the thickness to normal film, enabling it to go through laser/digital printers without melting in the machine.
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M 3 wordsTOP
Machinable / Mailing Wallet
An envelope for use on an inserting or mailing machine.
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Matt Coated
Envelopes made from coated paper designed for full colour overprint.
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Micron
This is a measurement which describes the thickness of paper in 1000mm
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N 2 wordsTOP
Natural Gas
A non-renewable fossil energy source formed deep beneath the Earth’s surface. Containing many different compounds, the largest component is methane.
Net-Zero Carbon Emissions
The amount of Carbon Dioxide released is balanced with an equivalent amount of Carbon removal.
O 1 wordsTOP

Opaque
A printed design or wash inside an envelope, typically for security purposes.
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P 6 wordsTOP
Pantone
A global reference for shades of print colours – each has its own individual number. Also referred to as PMS colour (Pantone Matching System).
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A method of supplying artwork via email, PDF stands for Portable Document Format.
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Perfecting
The term used for litho printing on both sides of an envelope at the same time.
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PIP
This is an abbreviation for ‘Pricing in Proportion’ – the way Royal Mail charge for the posting of mail.
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PPI
This stands for Postage Paid Impression e.g. 1st Class or Mailsort.
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R 2 wordsTOP

Reel Fed
An envelope manufactured from reels of paper. These are the most cost effective of all our envelopes.
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S 6 wordsTOP
Security Slits
Small slits in the flap of some self seal envelopes, offering tamper proof security.
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Self Seal
This refers to the sealing method where the envelopes two flaps are pressed together to form an instant bond.
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Set-Off
The term used to describe where the print on one envelope marks another.
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Shelf Life
The term to describe the useable life of an envelope, which is generally applied to Self Seal and Peel & Seal envelopes.
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Shoulder
This feature is located on the top of the side flaps of a wallet envelope.
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Side Seams
The seams at the sides of a mailing wallet, these can either be internal or external to suit the requirements of individual mailing machines.
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T 3 wordsTOP
Throat
The gap between the score line and the back flap of a wallet envelope, this can be a critical design aspect for inserting machines.
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Thumb Cut
Typically a semi-circular shape cut from a topless pocket or wallet, allowing access to contents inside.
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U 1 wordsTOP

UV Dryer
A special piece of equipment fitted to the back of an envelope press, enabling substrates such as matt coated envelopes to be printed without risk of set-off.
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W 5 wordsTOP
W & D
W&D stands for Winkler+Dünnebier, which is a world renowned make of envelope printing presses.
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W & D 102
A reel fed machine specifically used for producing gummed wallet envelopes up to an oversize C5 size.
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W & D 212/214
The ‘Rolls Royce’ of envelope presses, these machines are ideal for solid blocks of printed colour.
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W & D 249
An envelope press specifically for the production of larger format pocket envelopes, particularly C4 size.
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