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Choose a topic to find out more. We've tried to be comprehensive but there are sure to be things we have missed. Ask your questions and we'll do our best to answer.

If we don't know the answer we'll ask Bob!

 

A4, A3 etc.

Art Paper

Artwork

B4, B3 etc.

Backed Up

Bank

Bleed

Blind Embossing

Bond

C4, C3 etc.

Calendered Paper

Camera Ready Artwork

Cartridge Paper

CMYK

Coated

Collating

Colour Separation

Crease

Cromalin

Cyan

DIC

Digital Printing

Drilling

Dummy

Duotone

Embossing

Films

Finishing

Focoltone

Folio

Four-Colour Process Printing

Gravure

gsm

Halftone

Imagesetter

Imposition

Insert

Intaglio

Interleaving

Lamination

Laid Paper

Landscape

Line artwork

Lithography

Make Ready

Machine Minder

Mechanical

Offset Printing

Originals

Overs

Pantone

Paper Sizes

Perfect Binding

Perfecting

Printing Plate

Portrait

Postscript

Progressives

Proof

RA2, RA1 etc.

Register

Run-on

Rotogravure

SRA2, SRA1 etc.

Saddle Stitch

Scanner

Score

Screen Printing

Section

Separated films

Set-Off

Sheet Fed

Silkscreen

Special Colours

Stock

Three Colour Printing

Transparency

Two Colour Printing

Two Colour Machine

UV Varnishing

Web

Wet proof

Work & Turn

Work & Tumble

Wove Paper

 

See our special diagramatic sections dealing with:

Offset Lithography

Four Colour Printing

ISO paper sizes

 


Art Paper

Paper which has a coating usually of china clay. It can be gloss or matt and is suitable for jobs requiring a fine finish such as colour brochures and annual reports.

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Artwork

Originally the physical art (Sometimes referred to as Camera-Ready Artwork or Mechanical) prepared by the designer and including type, graphics and other originals. This was used by the printer to produce the printing plates.

Today the artwork exists almost wholly in electronic form. Photographs and illustrations are input to the computer using a scanner. All the elements are assembled using page layout software. Proofs can be made using colour laser or inkjet printers. The computer then separates the 'artwork' and produces high resolution films from which the printing plates are made.

 

Backed Up

When the reverse of a sheet is printed. See Work & Turn.

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Bank

A lightweight paper, usually less than 60gsm.

 

Bleed

Printed area which extends off the trimmed area.

It is not possible to print all the way to the edge of the paper sheet. To achieve this effect it is necessary to print a larger area than is required and then trim the paper down. Typically a designer would allow an extra 3mm of bleed to colour and image areas to allow for a little leeway when trimming.

 

Blind Embossing

A type of embossing where no ink is used. The design or text is only visible as a raised area on the paper.

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Bond

A basic paper, often used for copying or laser printers. The better quality bond papers, with higher rag content, can be used for letterheads.

 

Calendered Paper

Paper which has passed through hardened rollers during manufacture to produce a smooth surface.

 

Cartridge Paper

A heavy, textured paper often used for drawing.

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CMYK

Shorthand for the colours used in Four Colour Process Printing. Cyan, Yellow, Magenta and Black.

 

Coated

Paper which has received a coating to achieve a special finish. See Art Paper.

 

Collating

The process of assembling the various sections or sheets of a document in the correct order.

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Colour Separation

Separating a colour job into the elements required for printing. See Four Colour Process Printing.

 

Crease

A printed job can be creased mechanically to make folding easier. There are times when you might want a printed piece delivered flat for ease of storage and then do the folding yourself, manually.

 

Cromalin

The brand name of a colour proofing system produced by Du Pont.

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Cyan

The blue colour used in Four Colour Process Printing.

 

DIC

The brand name of a colour matching system produced by Dainippon Ink & Chemicals, Inc. A range of inks are specified and identified by number to produce standard results across the industry.

 

Digital Printing

A recent development has entered the market in the shape of digital printing. These systems work directly from electronic data and avoid the intermediate stage of films. They are very cost effective for short runs. The quality obtainable is not yet up to lithography standards but is improving steadily and is adequate for many purposes. Because these systems use an inherently four colour process there is no cost saving to be made from using one- or two-colour designs. Two popular digital machines are the Indigo E-Print and Heidelberg Quickmaster.

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Drilling

Making the holes in paper for use in a ring binder. Drills can neatly perforate a much greater thickness of paper than can the kind of hole punch you have in the office.

 

Dummy (1)

A plain white mock-up of a booklet or brochure - Not printed but made up using the intended stock. Most printers will make up a dummy if you ask nicely. This is the best way to get a feel for the finished product.

 

Dummy (2)

A mock-up produced by the designer to show how the finished job will look. This will usually involve colour prints from various sources and will therefore not be on the intended stock.

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Duotone

A two-colour halftone sometimes used in Two Colour Printing. Produces a tinted effect using a black & white original.

 

Embossing

Stamping a design into the paper to produce a raised effect. See Blind Embossing.

 

Films

Films are produced by an imagesetter from the artwork. They are used to produce the printing plates by a photochemical process. There is one separated film for each ink used. See Four Colour Process Printing.

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Finishing

Any process that follows the actual printing. Can include folding, creasing, stitching, binding and the like.

 

Focoltone

The brand name of a colour matching system produced by Focoltone International Ltd. A range of inks are specified and identified by number to produce standard results across the industry.

 

Folio

Printer's technical term for what the rest of the world calls a page number.

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Four Colour Process Printing

The most common system for producing full colour print. Originally the artwork and originals were separated using filters and four printing plates were produced.

The four ink colours are Cyan (Blue), Magenta (Red),Yellow and Black - often referred to as CMYK. Because the inks used are translucent, they can be overprinted and combined in a variety of different proportions to produce a wide range of colours.

The vast majority of magazines and colour books are produced using four-colour process.

See our detailed description of Four Colour Printing. With diagrams!

 

Gravure

A not very common printing process where the image area is etched below the surface of the plate (An intaglio process). Gravure is most often used for either very high quality or long run printing. The web version is sometimes referred to as rotogravure.

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gsm

Abbreviation for grams per square metre. This indicates the weight of paper or other stock. For example; A typical photocopier paper would be 80 gsm - a good letterhead paper might be 100 gsm - a postcard would be about 250 gsm.

 

Halftone

The method of producing a range of tones, such as a photograph or tinted area, by dividing the image into a series of dots. Dark areas have relatively big dots, close together. Light areas have small dots surrounded by white space. The number of dots used determines the quality of the image produced. In a newspaper the halftone dots are easily visible to the naked eye - the screen used can often be as coarse as 60 dpi (dots per inch). A colour magazine would typically use a screen of 150 dpi - An art book, 175 dpi or finer.

A halftone screen can be applied to a solid colour in order to produce tints of that colour.

 

Imagesetter

Output device used to produce separated films from digital artwork. It can be thought of as a very high resolution printer. Most systems use the Postscript page description system.

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Imposition

The layout of pages on the printed sheet so that they are in the correct order when the sheet is folded up and trimmed. Imagine a 16 page A5 leaflet printed on a single SRA2 sheet. The sheet is folded in half three times before trimming and stitching. If you look at the printed, unfolded sheet you will see that, for example, page 2 is adjacent to page 15 and half the pages are upside down! There are many different imposition layouts - some of them very complex.

 

Insert

Technical term for those irritating adverts that fall to the floor when you open a magazine. An insert is usually not secured to the main book or brochure and is sometimes referred to as a loose insert for obvious reasons.

 

Intaglio

A printing process where the image is engraved below the surface of the printing plate such as gravure.

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Interleaving

Introducing alternate sheets of blank paper between the printed sheets as they come off the press to prevent set off.

 

Lamination

A plastic coating which protects the printed surface and usually gives a high gloss finish. Most paperback books have laminated covers.

 

Laid Paper

Uncoated paper often used for business stationery which has a textured pattern of parallel lines similar to hand made paper. Compare to Wove Paper.

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Landscape

The orientation of the page so that the long edge is along the bottom. Sometimes referred to as horizontal. The opposite of portrait.

 

Line artwork

Artwork which contains no halftones such as company symbols or simple diagrams.

 

Lithography

By far the most common type of commercial printing.

See our detailed description of Offset Lithography. With diagrams!

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Make Ready

The processes involved in getting a press ready for a print run.

 

Machine Minder

The person who actually runs the press. The quality of a printed job is often dependent on the skill of the machine minder.

 

Offset Printing

Printing system where the paper does not come into contact with the printing plate. The ink is transferred from the plate to a blanket cylinder and then to the paper.

See our detailed description of Offset Lithography. With diagrams!

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Originals

The basic elements of the artwork. Includes photographs on print or transparency, illustrations, line artwork etc.

 

Overs

A quantity of printed material in excess of the amount ordered. It was once usual practice for a printer to charge pro rata for overs. This is much less common nowadays.

 

Pantone

The brand name of a colour matching system produced by Pantone, Inc of the USA. A large range of inks are specified and identified by number to produce standard results across the industry.

A reference such as PAN199 indicates a colour in the Pantone range, in this case a bright red. In a colour swatch book the number PAN199C would indicate how the colour looks when printed on Coated or glossy stock. PAN199U indicates how the same ink appears when printed on Uncoated or matt stock. Sometimes the difference can be quite dramatic.

It is worth remembering that Pantone inks provide a much greater range of colours than can be achieved using CMYK. This is important if trying to match work printed in four colour process with that printed in special colours.

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Paper Sizes

The most common system of paper sizes in Europe is the ISO standard. Most people are familiar with the A series which includes A4 the usual letterhead size. The C series is for envelopes - A C4 envelope being ideal for holding an A4 sheet. There is also a B series which provides intermediate sizes for the A series but this is rarely used.

The aspect ratio of ISO paper sheets is 1 to 1.414 (The square root of 2). This gives them a unique property: If you cut a sheet into two the resulting halves are the same proportion as the original. In other words a sheet of A4 when halved gives you two sheets of A5. All A size papers have the same proportions. The largest sheet in this series is A0 which is 841mm x 1189mm and just happens to be one square metre in area (ISO paper sizes are rounded to the nearest millimetre).

Two other series which you may come across are RA and SRA which are used by printers. They are slightly larger than the A series to provide for grip, trim and bleed.

See our Chart of ISO paper sizes. With diagrams!

Of course you can use any size of paper you choose. However, most paper merchants supply ISO sized stock so it is most cost effective to stay with A sizes.

Use of the ISO system is much rarer in the USA.

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Perfect Binding

A type of book binding where the pages are held in the spine by glue. Many magazines and most paperback books are perfect bound.

 

Perfecting

Printing both sides of a sheet in one pass through the press.

 

Portrait

The orientation of the page so that the short edge is along the bottom. Sometimes referred to as vertical. The opposite of landscape.

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Postscript

The brand name of a software standard created by Adobe. It is a page description language which is used by most graphics software and output devices to combine text, pictures and graphical elements into an electronic document and create output which can be used by the printer.

 

Printing Plate

The physical plate which carries the image. These can be made from a variety of materials. At the cheaper end of the market there are paper plates which are designed to be used once and thrown away. They are very economic for short runs such as small quantities of stationery.

 

Progressives

A set of proofs which show the different inks separately and combined in various permutations.

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Proof

A test print produced to show what the finished product will look like. These can be made in a variety of different ways and at different stages of the production process. The simplest form is a colour laser or inkjet print which can create a rough impression. It should be remembered that at this point there are still a number of stages through which the data has to pass and therefore a laser print cannot be relied upon as an accurate proofing method.

Photochemical proofing systems like Cromalin have for many years been the most popular method. The colour print is produced directly from the separated films and therefore gives an accurate interpretation. Sometimes the colours can be even sharper and more vivid than can be achieved on the press and there is a danger of creating unrealistic expectations in the client.

The most accurate method is a wet proof. This involves using a special proofing press designed for very short runs and actually printing a quantity of sheets using the real stock and real inks. Of course this requires producing the films and plates, not to mention the cost of Make Ready which makes wet proofing a very expensive option, particularly if corrections are required. This is a bad time to start looking for typographical errors.

Increasingly popular are digital proofing systems which aim to simulate the Cromalin type proof. They are essentially very high resolution colour printers which make use of colour management techniques for their accuracy.

Whatever system you choose it is certain that proofing is a good thing which can save a lot of heartache and cost later on. Sad to say, many clients with an eye on the budget tend to regard proofing as an unnecessary expense. "There's always time for a reprint".

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Register

When printing with two or more colours it is necessary to align the different plates. This is known as register. On the edges of an untrimmed sheet you will see small target shapes called register marks which are used for accurate positioning. A printed piece which is out of register will have an unfocussed look.

 

Run-on

Often when a printing price is quoted it is given as a figure for the basic job plus a figure for additional copies. For example the price may be 2000 copies at £300 with £25 for a 500 run-on. This enables you to calculate a range of prices for different quantities.

It is very important to note that the run-on price is for copies printed at the same time as the main run. For instance, in the example given, you could not have 2000 copies today and then expect to have another 500 at some future date for just £25. In many cases the set-up and Make Ready charges represent a large proportion of the print cost.

 

Rotogravure

The web version of gravure.

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Saddle Stitch

A simple way of assembling a small booklet or magazine with a wire stitch through the fold. You may call it stapling but printers call it stitching.

 

Scanner

A device for turning a piece of artwork into a digital form. Transparencies, prints and illustrations are scanned so that they can be accessed by software designed for image manipulation and page make-up. For many years the industry standard was the drum scanner, a rotary system which produced very high-resolution scans. Recently flat-bed scanners, such as you might use with a PC, have risen dramatically in quality to the point where the better models are suitable even for high-end work.

 

Score

Heavier paper and boards need to be scored with a rule to make folding easier.

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Screen Printing

This is a process where the ink is transferred to the printing surface by being squeezed through a fine fabric sheet stretched on a frame. The screen carries a stencil which defines the image area. The process can be manual or mechanical but is most suitable for short runs. Screen printing is usually used for large poster work and display material. It comes into its own when printing to difficult or unusual surfaces such as clothing or plastic objects. It is often referred to as silkscreen printing although the screens are generally made from artificial fibres.

 

Section

A folded sheet which is assembled with others to make up a book. For example an A2 sheet will provide a section of eight A4 pages when folded twice. A 20 page booklet would therefore require two 8-page sections and one 4-page section. These sections are then saddle-stitched together. Larger booklets of, say, more than sixty pages could be perfect bound.

 

Set-Off

A printing fault where ink transfers from a sheet to the one below as it leaves the press creating an undesirable ghost image. This can be cured if necessary by interleaving. The machine minder should be able to correct the problem.

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Sheet Fed

A press which prints by taking up one sheet at a time. This is the system you are most likely to come across. The opposite of web.

 

Special Colours

This refers to colours which are produced using specially mixed inks from one of the commercially available colour ranges such as Pantone, DIC or Focoltone. They are most commonly used when using Two Colour Printing.

To print colours outside the range of four colour process it is necessary to use special inks. If for example the exact colour of a company logo could not be achieved from a CMYK mix then it would be necessary to print a fifth plate with the special ink. It is not unusual, where an elaborate effect is required, to print in six or more colours. There are presses which are capable of printing eight different plates in a single run through the machine.

It is worth bearing in mind when choosing a colour for a company logo that sooner or later you will want to print a colour brochure using four colour process. A vivid ink which you have chosen from the Pantone book may not have an acceptable CMYK equivalent. You may be forced to change the company colour or swallow the ongoing expense of a fifth plate.

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Stock

A general term for any paper or board which is used as a printed surface.

 

Three Colour Printing

Theoretically it is possible to produce an adequate range of colours using just Cyan, Magenta and Yellow. In Four Colour Process Printing the black plate adds shade and depth reducing the amount of ink required. Today this system is very rare.

Three colour printing may also refer to the use of three special inks or black combined with two specials.

 

Transparency

The preferred medium for photographs intended for printing. Transparencies generally have sharper images and better colour than photographic prints. The three most common sizes are 'five-by-four', 'two-and-a-quarter' (both in inches) and 35mm - the same size as your holiday slides.

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Two Colour Printing

Two colour printing is commonly used for stationery because of its cost-effectiveness. The typical design includes a special colour such as a Pantone ink along with black. The special ink is for the 'company colour' for use on the logo and the black is for text. In addition, tints of both inks could be used to produce variations of the colour and greys respectively. For example, if a strong blue is chosen as the main colour then the opportunity exists to have a pale blue tint, perhaps as a background 'ghost' image. A range of greys is also available from tints of black.

Two colour printing can be an economic way of producing brochures and catalogues if full-colour images are not required. There are creative options such as duotones which can be considered if the subject matter is suitable.

 

Two Colour Machine

A press which prints two colours during one pass through the machine. It is possible to print four colour process by printing Cyan and Magenta, changing the plates and then sending the sheets through again to print the Yellow and Black.

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UV Varnishing

A method of adding a gloss finish to printed surfaces. The advantage of UV varnishing is that it is similar to printing an extra colour and can be applied to selected areas to produce special effects. The UV refers to the Ultra-Violet lamp under which the varnished sheets pass for rapid drying.

 

Web

Nothing to do with the internet. A web printing machine is one that accepts the paper on a large roll (the web). These are very fast presses and are only economic for long run and high volume work. Most people have seen film of newspapers being printed - this is a web process. The majority of magazines you find in the newsagent have been printed by web.

The opposite of sheet fed.

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Work & Turn

When a whole job is printed on one side of sheet, the sheets turned and printed again using the same plates. For example, a single sheet A4 flyer is printed with back and front adjacent to each other on one side of an SRA3 sheet. The sheets are flipped over and printed with the same plates again. When trimmed you have A4 sheets with a different image front and back. The advantage of this technique is to save a plate change and make-ready cost. You may also here the expression Work & Tumble which is so similar as to only concern the pedantic.

 

Wove Paper

Uncoated paper often used for business stationery which has no obvious surface texture or pattern. Compare to Laid Paper.

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