Directory of Printing Terms

Acetate

A transparent sheet placed over originals or artwork, allowing the designer to write instructions and\or indicate a second color for placement.

Acid-free Paper

Paper created from pulp with little or no acid so it does not deteriorate over time. It is also known as alkaline paper, archival paper, neutral pH paper, permanent paper and thesis paper.

Additive Color Mixing

This is the process of producing color through the addition of different colors of light. Computer and television screens use thousands of red, green, and blue phosphor dots, which are so small and close together that the human eye cannot see them individually. Instead, the eye sees the colors formed by the mixture of light.

Adobe

Adobe Systems Incorporated, headquartered in San Jose/California, is a leading software manufacturer in the field of graphics and image editing. Established in 1982, the company's products include the image editing program "Photoshop", the illustration program "Illusrator" and the desktop publication programs "InDesign" and "Pagemarker". Adobe is also the originator of the page description language "PostScript" and the device - independent data format "PDF" (Portable Document Format).

Application server

An application server is a network server in which a group of programs are collectively integrated into a Web server's environment. Instead of having individually installed programs, the network's users have access to the server program. These applications are connected to an Application Program Interface (API) which allows higher-level tasks to be performed remotely. Another advantage of these applications is that licensing requirements can be more easily met, as the users do not usually have their own hard drive, which prevents the installation of so-called pirate copies. It is also possible to install the latest software available on all computers in the network with a single update on the server. This kind of server enables a user at a Web page to perform sophisticated interactions, such as querying a database or running other programs loaded on the server.

Art printing paper

A premium-grade stock coated on both sides (C2S), preferable for the high-quality reproduction of color prints. Art printing papers usually have a very smooth, glossy surface, though some have a matte or semi-matte finish. They allow illustrations to be reproduced by offset or letterpress in much finer halftone screens.

Back Up

(1) To print on the second side of a sheet already printed on one side. (2) To adjust an image on one side of a sheet so that it aligns back-to-back with an image on the other side.

Barcode

The barcode is used to display characters in such a way that they can be read easily by machine. The code consists of a system of narrow and wide, dark and light strips. One of the most common applications for barcode markings is the EAN code for identifying all types of goods. The EAN code also defines the barcode’s representation of the individual figures. Other code systems are also available, including those for representing letters and numbers.

Bitmap

The simplest format for graphics, where the pixels within a two-dimensional coordinate system are described by an x,y value (position of the pixel) and a color value.

Black generation

Black generation is a term which describes how the color black is used in a set for four-color printing. In theory, black is not required in the CMYK color system for representing various hues of an image. In practice, however, it is used whenever contrast and detail need to be enhanced in dark areas. The term short black or skeleton black is applied if the color is only used for this purpose (for which only a small amount of black is required). Black can also be used in color mixes to replace equal components of the three chromatic colors cyan, magenta and yellow (Under Color Reduction), thereby reducing the total volume of ink actually required in the print. This is known as ‘long black’.

Blanket

Rubber-coated pad, mounted on a cylinder of an offset press, that receives the inked image from the plate and transfers it to the surface to be printed.

Blanket cylinder

The blanket clamped around a cylinder is the core element of offset printing. It transfers the printed image from the printing form to the paper. The process of depositing the ink on the blanket also gave rise to the term “offset printing”. Blankets enable consistent printing over large areas and are ideal for rough or grained papers. The blanket on the cylinder is usually 1.65 or 1.95 mm thick and consists of two, three or four fabric interleaves in addition to the actual covering layer. A distinction is usually made between the conventional blankets, which can be deformed but not compressed, and the compressible, air-cushioned blankets. Standard DIN 16621 sets out the requirements for “blankets for indirect lithographic printing (offset printing)”.

Bleed

Printing that extends to the edge of a sheet or page after trimming.

Blueprint

In printing, blueprint was the term used for monochrome prints of finished printing copy, owing to their faint blue color. Today, even corresponding, simple black-and-white prints are generally referred to as blueprints. They serve as proofs for checking the completeness, position and content of the individual graphic elements (texts, images, etc.).

Bogus paper

Bogus paper is a very simple type of paper that is made exclusively from unsorted waste paper. It usually has a gray, or sometimes brownish tint, and a weight of 80 g/m 2 or more. Bogus paper is primarily used as a starting material for corrugated board.

Brochure

A brochure consists of a cover stuck or stitched directly to the spine of a single-layer or multi-layer block. The cover generally has the same format as the book block and is made either of material similar to the interior of the brochure or of card. The brochure was originally a temporary form of binding used until the purchaser of a book had opted for a high-quality book cover, which was often very expensive. Nowadays, this binding technique is used as a low-cost mechanical production method of producing the finished print product.

Calibration

In a general sense calibration refers to the task of coordinating devices to ensure correct operation. At the prepress stage, input and output devices – monitors, scanners, imagesetters and so on – are generally calibrated to test how colors are depicted and to take corrective action if necessary.

Chip Board

A low grade of cardboard, used as a backing for pads of paper, a stiffener for photographs in mailing, etc.

Chromo paper

Chromo paper includes woodpulp or woodfree stocks coated on one side. The coating is always waterproof and is designed for maximum embossing, varnishing, and bronzing performance in offset environments. Chromo paper is used mainly to make labels, wrappings, and cover paper

Chromolux board

Chromolux is a brand name for a high-gloss, cast-coated board that is white on one side.

Clean proof

A page without any misprints.

Client/server

A relationship in which one computer program (the client) requests information from another computer program (the server), whereby the server responds in fulfilling the request. In terms of "client/server architecture," it is the design model for applications running on a network. The bulk of the back end processing, such as performing a physical search of a database, takes place on a server. In terms of a "client/server network," LAN resources are allocated so that computing power is distributed among the computers in the network, but some shared resources are centralized in a file server. With the advent of powerful individual workstations, most computers can act as both client and server in different situations; this is often described as "n-tier computing," where "n" refers to the multiple levels of clients and servers that exist. For security reasons, the client/server model requires user authentication.

CMYK

CMYK (an acronym for Cyan, Magenta, Yellow, Black) designates the color model usually employed in printing technology which uses the basic colors cyan, magenta and yellow. The fourth “color” is black, which is used to ensure a visually satisfying black tone.

Coated paper

Papers are coated to improve surface gloss, lustre, whiteness and printability. The coatings consist of natural pigments, a binder, and various process materials. The procedure is carried out on special coating machines in the paper mill. Coating can have many different effects, giving the paper a surface that ranges in appearance from very shiny (gloss enamel) to somewhat muted (satin velvet) to dull (matte). Cast-coated papers have a shiny mirrored surface achieved through drying on a hot, highly polished cylinder. Paper used to be coated right on the paper machine, which is why the umbrella term "machine-coated paper" is still used to mean coated offset, gravure, and letterpress stocks.

Cockling

When the relative humidity is lower in the environment than in the paper, the edges of stacked sheets can dry out and contract (tight edges), causing the paper to buckle in the middle.

Collating mark

The collating mark is the name given in book printing to a short line which is printed in a staggered position in the gutter between the first and last page of each sheet. Once the sheets have been folded and collated, the lines appear on the spine of the book block, enabling the sequence of the individual sheets to be checked based on the position of these lines.

Color density

The term color density describes the optical density of areas printed in color. This value is important when monitoring quality in printing processes and can be measured using special instruments (reflected light densitometers). However, it is only ever possible to compare the color densities of an individual hue with each other.

Color management

Color management refers to the control of color reproduction in a digital graphic production process. The various input and output devices from the scanner to the printing press support different color spaces, depending on the device. In order to standardize the way colors appear throughout the production process, color profiles are generated for the devices and processes involved in the process. The combination of these color profiles makes it possible to calculate the coefficients necessary for data conversion. Those colors in a given color space that cannot be displayed in another are approximated as closely as possible.

Color profile

The color profile of an image input or output device (scanner, monitor, printer, printing press, etc.) is an element of color management which indicates how the color information supplied by the device behaves with respect to a superordinate, device-neutral color system (e.g. the CIELAB color space). Manufacturers supply color profiles with professional devices. To ensure high-quality results, profiles need to be created individually using special measuring instruments. This procedure may need to be repeated at regular intervals.

Color proof

A color proof is used for a binding, advance check of the colors of a printed product. It entails much less effort than a press proof on the press itself and can also be produced away from the printing site. In addition, there has recently been a major drop in the price of printers that reliably produce high-quality color prints. The prerequisite for an accurate color proof is, however, the reliable control of the (electronic) preprint process with a color management system that also includes the press and the paper used.

Color separation

A color separation is the color component of a digital print original which corresponds to a color in multicolor printing. The most popular four-color printing process is the CMYK color model which requires four separations in the colors cyan, magenta, yellow and black for producing the corresponding printing plates. The color separations which together form a complete color original is known as a color set.

Color space

A color space is the set of all colors which can be portrayed by a single color system. Well-known color systems are CIELab by the CIE, Kodak's PhotoYCC, RGB used in PCs and CMYK used for printing. CIELab and PhotoYCC are suitable for processing and storing images. The color spaces of the RGB and CMYK systems on the other hand are noticeably smaller. In addition CMYK data is only ever useful for a given printing process and cannot be used again in other output media.

Computer-to-plate

In the computer-to-plate process, data from the computer is imaged directly onto the printing plate, without using film as a transference medium. This reduces costs, but the printing foils used in this process wear out faster than conventional printing plates and may need to be replaced on a periodic basis. What is more, depending on the process, the foils cannot always be stored once they have been printed. Recently, new materials, which use thermal energy instead of visible light for imaging purposes, have made it possible to process film in daylight conditions and to develop film without using chemicals.

Computer-to-print

The term Computer-to-Print covers all printing processes which do not require physical printing plates. Using processes derived from computer technology – e.g. laser printing – appropriately equipped presses can print directly from suitably processed data. Computer-to-Print is ideal for short runs, and in particular personalized printing.

Concertina fold

A concertina fold is the continuous parallel folding of brochures and similar printed products in the manner of an accordion, where the fold is alternatively made to the front and back.

Content

The textual and graphical information contained in a Web site, as well as the structure and design in which the information is presented. Writers and companies who create this information are known as content providers. Content is one of the three big C's (content, commerce, and community), and Web sites often get judged and rated on the quality, quantity, and navigational flow of this information.

Corporate design

Corporate design is part of corporate identity and refers to a company projecting a consistent, identifiable corporate image through its communication media, such as brochures, catalogs or packaging. This includes graphic elements, such as a distinctive company logo, the company's 'house colors' or a particular typeface. In many cases corporate design also encompasses product design and can even extend to include the architecture of the company building.

Corrugated board

Corrugated board is a packaging material which, in its simplest form, consists of a corrugated sheet of paper which is produced using two intermeshing, grooved rollers with the application of pressure and heat, with flat paper sheets glued to either one or both sides. Corrugated board was invented in the USA in 1871 and, thanks to its excellent packaging characteristics (high strength and low weight) quickly grew in popularity. 1.2 million tons of the product are currently produced in Germany each year.

Dampening system

The dampening system of offset presses has the task of drawing a thin film of dampening solution – water with a component of isopropyl alcohol and other additives – over the non-printing areas of the form. We can distinguish between, on the one hand, vibrator-type dampening systems and dampening systems where direct contact exists between the dampening solution holder and a vibrator cylinder and, on the other hand, centrifugal, turbo or brush-type dampening systems which do not have this direct contact. With indirect systems, the dampening system feeds the dampening solution to an inking form roller which in turn feeds ink and dampening solution in dispersion form to the printing plate.

Data compression

In computer engineering, "compression" is the term used for the reduction of the memory space required for data by optimizing the binary notation of the information. Depending on the nature of the original data and their coding, compression ratios of 1 : 100 and more can be achieved in this way, thus saving memory space and/or transfer time. A distinction is made between compression methods that involve a (more or less acceptable) loss of information and "non-lossy" methods. Typical "lossy" methods are JPEG for images and MP3 for music. Methods for compressing numerical data, such as MNP5 and V.42bis for data transmission, and also compression methods for files (zip, lha, rar, etc.), are of the non-lossy type for obvious reasons.

Data mining

The term data mining embraces a range of processes that are used to glean information which is not immediately obvious from databases. Data mining involves statistical and artificial intelligence methods, and can reveal information about the typical behavior of groups of people based on characteristics that at first glance do not seem to be linked. Data mining is a favorite tool of banks and insurance companies, for example, who collect huge quantities of data on their customers.

Database

A Database is an electronic filing system; An organized collection of information, characterized by the use of data fields, it provides a foundation for procedures such as retrieving information, drawing conclusions, and making decisions. Traditional, computerized databases are organized by fields, records, and files. A field is a single piece of information; a record is a complete set of fields; and a file is a collection of records.

Default

A computer software setting or preference that states what will automatically happen in the event that the user has not stated another preference. For example, your computer may have a default setting to launch or start Netscape whenever a GIF is opened; if you prefer to use Photoshop whenever you need to view a GIF, you can change the default setting.

Dialog marketing

The term dialog marketing includes all company activities aimed at addressing potential customers directly in order to obtain a direct response. One typical tool of dialog marketing is mailshots (personalized communications) containing various response options. Many advertising professionals regard the Internet as the customer dialog medium of the future.

Digital camera

Instead of conventional light-sensitive film, digital cameras use highly-integrated components (CCD chips), which convert the image captured by the lens into digital data. This circumvents the use of film imaging, film development and scanning. In print and non-print media production, this saves time while also offering greater flexibility. There are digital cameras available for a whole range of applications, from recreational use to use in a professional capacity. As a rule studio cameras use separate digital units instead of traditional film cassettes.

Digital holography

Digital or synthetic holography is the term used for generating holograms, i.e. illustrations in the form of interference patterns, through computer calculations instead of light interference. Future applications for digital holography include high-capacity, long-term data storage devices based on plastic foil and ultra-small, forgery-proof markings for packaging, etc.

Digital photography

As an alternative to conventional processes which use film imaging and film development, digital photography uses cameras which capture images directly in digital form. The image data is transferred by means of special storage media or a data interface to a computer for further processing.

Digital printing

In a general sense, digital printing refers to printing processes in which the information is transferred from the computer directly onto the paper, without need for film and printing plates. It links color printing technology with the printing press' mechanical system. Digital printing cannot achieve the same level of quality as conventional printing processes, but it is faster and more cost-effective for small print runs and allows special techniques such as personalized printing or printing-on-demand.

Digital signatures

A digital signature is a type of "seal", which is created using a chip card and is based on encryption software (mathematical processes). Digital signatures are used in electronic communication to provide a legal alternative to the handwritten signature. These are ideal, for example, for electronic tax returns, home banking and electronic transactions (e-commerce).

Dimensional stability

Dimensional stability measures how much a paper's dimensions change when its moisture is altered. This is a key criterion affecting a stock's suitability for multicolor offset printing.

DIN sizes

These standard metric sheet sizes are widely used outside the United States. The most important ones belong to the A series, in which the next-smaller size has a length corresponding to half that of the next-larger size. They include A4 (210 x 297 mm) and A3 (297 x 410 mm).

Document paper

Document paper is one of the highest grades of paper and bears a real watermark. The grade is generally used for official documents and certificates, and features special properties to that end.

Dot gain

Dot gain is a term used to describe the growth in the size of screen dots during the prepress and press stages. This can have very different causes depending on the process stage in question. The effect is most marked in areas of medium image brightness and should be taken into account when performing settings in order to prevent color shifts during print.

Dummy

Sample of a print product which is designed to demonstrate the production features of a product such as format, page count, paper grade, finishing and binding. The pages remain unprinted.

Dummy text

Dummy text is the term used for meaningless text whose purpose is to communicate the intended typographic impression of layouted pages or to reserve a space. Dummy text should be instantly recognizable as such - otherwise, as has occasionally happened, it may erroneously end up being left as valid text and printed.

EB inks

EB inks are printing inks that are dried by electron beams. Similar to UV inks, which are cured by ultraviolet light, EB inks are cured by means of polymerization. This is brought about by the direct effect of the electrons on polymerizable substances. Unlike UV inks, special initiators are not required for EB inks. As a result, EB inks are, among other things, better in storage. Their special advantage is considered to be the option of processing them in thick layers, because the electron beams penetrate deeply. However, curing must be carried out in an oxygen-free environment (under a gas blanket) in order to avoid oxidation of the ink and the printing material caused by the high-energy electrons.

Effect coating

In the printing technology sector, effect coatings are coatings that are used to achieve special effects. Generally speaking, these are pigmented coatings that vary greatly, according to the pigments in the ink, the shape and the size of the particles.In screen printing, for example, layers can be printed so thickly that you can actually feel the printed structures. These applications can be used, for example for wallpaper printing, since they enable relief effects to be achieved without any need for embossing tools. Effects can also be created using ‘scratch-and-sniff’ coatings. These contain aromatic materials that are either released by scratching or give off their smell continuously.

Electronic signature

See digital signature.

Euro scale

The Euro scale is a color scale for the CMYK four-color model which is standardized in Europe in accordance with DIN 16 539 for offset printing and DIN 16 538 for letterpress printing. This defines the printing colors yellow, magenta, cyan and black according to hue, saturation and print sequence and enables them to checked under standardized conditions.

Ferro-gallic ink

Ferro-gallic ink is a very durable type of ink that consists of gallic acid (also known as tannin - 3,4,5-trihydroxybenzoic acid, chemical formula: C6H2(OH)3COOH), iron sulfate and possibly a binder (gum arabic). Ferro-gallic ink has been known since antiquity. It got its name from the oak galls used as a source of tannin. The ink was used for documents of all kinds until the advent of chemical dyes in the very recent past. When fresh, pure ferro-gallic ink has only a pale color. Only after being applied to paper and exposed to atmospheric oxygen does it form a strongly coloring, black pigment. It is insoluble in water and thus very difficult to remove. After extended periods of time, ferro-gallic ink attacks paper and parchment, causing what is known as ink corrosion.

FGD

The Forschungsgesellschaft Druckmaschinen e.V. (FGD -Printing Press Research Association) headquartered in Frankfurt was founded in 1955 by leading German printing press manufacturers as a non-profit organization. It acts as a coordinating office between the printing press industry and the research activities in the field of printing presses and printing processes. In particular, it works together with the Institut für Druckmaschinen und Druckverfahren (IDD -Institute for Printing Presses and Printing Processes) at Darmstadt University of Technology.

Fine Paper

Fine paper is the general term used to describe paper of superior quality. In production, particular attention is given to the stability of the surface as well as good, even transparency (also with watermarks) and of course good printability.

Finishing

In printing, the term "finishing" is used to cover the operations that take place after the actual print run and lead to the finished printed product. Depending on the type of product, this includes folding, collating and trimming of the printed sheets, as well as binding and possibly also packing.

Flexographic printing

Flexographic printing, a letterpress process, uses photopolymer wash-off printing plates (letterpress plates) or variations of these (rubber printing plates) as printing forms. Using low-viscosity ink it is possible to print on very different materials with screen rulings of up to 54 l/cm. Flexographic printing is a very fast, uncomplicated printing process suitable for packaging printing and multi-color newspaper printing.

Fluorescent printing inks

Fluorescent printing inks are stimulated into shining, thus changing color, when exposed to ultraviolet (UV) light. There are various types that react to UV light of different wavelengths. Fluorescent printing inks are used for protection and to identify documents at risk of being forged.

Fold

In bookbinding a sharp break or bend in the papers. By folding either a product with consecutively numbered pages or simply a smaller format is produced. Folding is generally done by special folding machines. A distinction is made between right angle and parallel folds. In right angle folding the next fold is always at a right angle to the previous one. In parallel folding, always parallel to the first.

Folding machines

A distinction is made between two main types of folding machine. First the knife folder, where a blunt edged knife presses the paper between two continuously moving rollers. The paper is caught between the rollers and carried away, a fold being made where the knife made contact. The buckle or plate folder feeds the paper end first between a pair of continuously revolving rollers. Both methods of folding ca be combined in one machine - the combination folder.

Font

Font is the word for a type face. A font usually has several styles in various weights and versions.

Full ink coverage

The full ink coverage is the smallest quantity of ink that can completely cover the surface of a particular printing stock so that no gaps are visible. In offset printing, the full ink coverage for smooth coated art papers is 1.5 to 2 gsm, and for uncoated papers is in the region of 3 gsm.

GATF

GATF (Graphic Arts Technical Foundation) is a technical association for the printing industry which is based in Sewickley, Pennsylvania, USA. The organization joined forces with the Printing Industries of America (PIA) at the start of 1999 and has some 14,000 members in 60 different countries.

Gatherer-stitcher

The gatherer-stitcher (also known as a gang-stitcher) is a device for stitching printed products and creating issues – magazines, brochures, etc. – from printed and folded sheets. The print sheets and the jacket are put together in the correct order, aligned and then stitched using wire staples. Finally, the volume is cut on three sides. This separates the sheet folds that do not lie on the spine edge, and thus the issue takes on its familiar shape.

GCA

The Graphic Communications Association is the former name of the International Digital Enterprise Alliance (IDE Alliance).

Ghosting

Ghosting is an error which can occur with indirect printing processes such as offset printing. This is produced when screen dots have double or multiple contours and can occur in single-color printing, but more often in multi-color printing. Faulty printing of this type increases the screen tonal value and leads to dot gain. This slight shift in the position of the printing elements is caused by register fluctuations during printing, which may themselves be caused by the paper or the press.

GIF

GIF stands for Graphics Interchange Format, and describes a data format for space-saving storage of images and graphics. It works using lossy compression, and allows 256 colors to be displayed from any pallet. The data format was introduced by the Compuserve online service in 1987, which makes it one of the oldest of its type. GIF remains one of the most widely-used formats for online publication, and also allows animated images to be displayed in a modified form (“animated GIF”).

Gigabyte

A unit of measurement approximately equal to 1 billion bytes. A gigabyte is used to quantify memory or disk capacity. One gigabyte equals 1,000MB (actually 1,024 megabytes). One thousand megabytes or one billion bytes.

Glassine

Glassine is a highly greaseproof, but not wet-resistant paper grade made of finely ground pulp. It is highly supercalendered and therefore relatively transparent.

Glyph

A glyph is a symbol carved in stone. In typography, a glyph is a letter which a character set contains in several forms. The letter “s”, for example, has this property in both the German and Greek alphabets.

Gradation

Gradation The gradation (or gamma value)of a picture –such as a photograph or an electronic image stored on a computer –indicates the steps in which the gray values of the original are rendered. With a flat gradation, there are many steps between white and black, while a steep gradation has fewer steps or even just pure black-and-white. This is also referred to as a "soft" to "hard" rendition.

Grain long, grain short

These two terms are used to indicate whether the paper web should travel through the paper machine lengthwise or widthwise. This is generally indicated by marking whether the width or length of the paper should correspond with the machine's reel width. The fibers (and thus the grain) lie parallel to the edge not indicated.

Grammage

The standard international unit of measurement for paper weight, expressed in grams per square meter, or gsm. Grammages range from 7 to approx. 225 g/m2 for paper, and approx. 150 to 600 gsm for board. The system differs in the U.S., where the term "basis weight" is used, i.e. the weight in pounds of a ream (500 sheets) in the basic size for a grade of paper.

Gravure printing

This printing process is used in high-output rotary presses. Here the printing elements take the form of small cells on the surface of the gravure form cylinder. The print image is generally transferred onto the cylinder by means of electromechanical engraving using a diamond stylus. During the course of the printing process, the printing cylinder is entirely coated in ink. A doctor blade then removes the excess ink from the surface and the only ink remaining is the ink in the cells. Then a rubber roller presses the paper web against the printing cylinder and the ink remaining in the cells is applied to the paper.

Grippers

Grippers are the mechanical clamps used to transport the sheets of paper in sheetfed presses. Grippers grip the individual sheets and feed them into the printing unit. The printing unit’s rollers are equipped with further grippers, which fix the sheets in place for the various stages of the print process. The printed sheets are output in a similar way at the end of the printing process.

Halftone

Halftone is the term used to designate a contone image which has been prepared for printing using screening technology. This is a pure black/white or full-tone original which uses screening to simulate contones. The inventor of halftone technology is considered to be Georg Meisenbach (1841-1912), from Nuremberg, who in 1882 patented a screen that he had produced (DRP 22244).

Handfolding

Folding a sheet by hand using a "folder", a flat, smooth piece of plastic about 15 cm long. Only special versions in limited editions are still folded by hand.

Hard proof

The term "hard proof", as opposed to "soft proof", covers the processes for simulating or checking printed results that produce a material result, generally a hardcopy print. Depending on the characteristics to be checked, a distinction can be made between blueprint, imposition proof (layout proof), color proof, screen proof and press proof (also known as a machine proof).

Heat-set

Heat-set inks are printing inks that are essentially dried after the printing process by means of brief heating. This is achieved using hot air at temperatures between 120 and 150 ºC. Heat-set inks are used in rotary offset printing.

Hologram

A hologram is a three-dimensional image created by holography. It is not obtained by focusing light on an image converter (photographic film, optical sensor) through a lens. Rather, the interference image which results from interaction of the light reflected from the object to be imaged with a reference beam of the light source is recorded. This method demands extremely coherent light (i.e. synchronously oscillating light), such as that generated by a laser. Strictly speaking, viewing also requires coherent light on which the hologram superimposes the same interference image that it was produced with. If you make concessions as regards the accuracy of detail, holograms can also be viewed in normal light, in which case direct light produces better results than indirect light.

Host

A computer that functions as the beginning and end point of data transfers. It is most commonly thought of as the place where your Web site resides. An Internet host has a unique Internet address (IP address) and a unique domain name or host name. A host can also refer to a Web hosting company.

HPGL

Originally, HPGL (Hewlett-Packard Graphic Language) was a command language for driving plotters developed by the American manufacturer Hewlett-Packard. Today, many printers can also print out HPGL-encoded graphics.

Hue

Hue, defined within the context of a color space, is a term used to identity a (white) paper's exact shade. Not to be confused with whiteness, which is a different property of paper.

Illustration printing paper

Illustration printing paper is made from chemical pulp and may have a slight woodpulp content. This is a coated stock that is often calendered as well. It offers opacity similar to that of woodpulp paper, features excellent nonaging properties, and does not yellow.

Imposition proof

Like the blueprint, the imposition proof (or layout proof) is mainly intended for checking the content and completeness of the elements of printing copy. In contrast to a blueprint, this proof is in color, although the colors are not binding. Large-format inkjet printers are mainly used for printing imposition proofs of this kind today.

Imprint

The imprint is the information required by German publishing law which stipulates that the name of the publisher and printer of printed goods must be stated. In recent times, this has also extended to Internet publications. As a rule, the imprint also contains further details, some of which are required by law, such as the name of the editor responsible, the editorial address, information on how to advertise in the publication and on sales, and also a copyright notice.

InDesign

The InDesign software package from Adobe is a more recent program for computer layouting and typesetting, comparable to the familiar QuarkXPress. InDesign is available for both Windows and Macintosh computers. The special features of the software stated by the manufacturer are the extensive options for graphic design, such as texts on paths, nested text and graphics frames, surfaces and contours with color gradations, the scaling and bending of text and graphics, as well as paths in the form of Bezier curves (Curved lines defined by end-points and control points. Named after the french mathematician Pierre Bezier).

Initial

The initial is a letter placed at the beginning of text or paragraph, which is emphasised . It is larger than the body text, so that it spans two or three lines. In old handwritten material, initials are characterised by special color and decoration. The first initial can be found in the Greek and Copt scripts of the 4th century.

Inkjet paper

A surface-finished grade of paper designed to quickly absorb the tiny droplets of ink that an inkjet printer sprays in quick succession. It includes properties that prevent ink from running or smearing. Brown-colored paper (also called sulfate paper) consisting at least 90% of virgin, generally unbleached sulfate pulp. Known for its outstanding strength and durability.

Inkjet printing

Inkjet printing is a printing process where minute drops of ink are applied to the surface to be printed by means of a jet. The jet is applied using either piezoelectric or thermal technology. Color inkjet printers now work with up to six colors and well over a hundred individual jets. Nowadays, depending on the process, they are capable of achieving the same standard as high-quality four-color printing.

Inline processing

In the print industry, inline processing is the term used if the process takes place directly on the press or the modules required for that particular stage of production are linked firmly to the press. These can include coating, folding, stitching or quality control devices.

Integrated publishing

The digital linkup of all production stages in the print process - including electronic job input, prepress, press, postpress and preparation for dispatch – is known as integrated publishing. The International Cooperation for Integration of Processes in Prepress, Press and Postpress (CIP4), which involves more than 100 companies, strives to promote the integration of such computer-assisted processes within the graphic arts industry.

Job Definition Format

The Job Definition Format (JDF) grew out of an initiative by Heidelberger Druckmaschinen AG, Adobe Systems, MAN Roland and Agfa which is now supported by CIP4. It forms the basis for the non-proprietary integration of print processes. JDF is based on the XML formatting language and embraces a definition for describing print jobs (job tickets), a message format and an associated transfer protocol. The new standard succeeds the Postscript-based Print Production Format supported by CIP3 until mid-2000 and in future will also embrace business management aspects of the print process (from costing and quotation to billing).

Job ticket

The job ticket is a digital 'job folder' at the prepress stage of the production process. It is used to store instructions relating to imposition operations, trapping and OPI, as well as output parameters and printing and finishing information.

JPG (JPEG)

JPEG is a common method, developed by the Joint Photographic Experts Group, for compressing image files in RGB mode. It can reduce the file size by up to 95 percent. It involves a loss of image information, although the degree of compression can be selected such that these losses remain within acceptable limits. JPEG requires no license and is internationally standardized (ISO 10918). It uses the "Discrete Cosine Transformation" (DCT) method, where image sections of 64 pixels each are processed. A new compression method, known as JPEG 2000, is currently being developed. It uses what are known as "wavelets" and is said to be able to compress images by 20 percent more than JPEG. The image quality also suffers less at high compression rates, as the image is processed as a whole. Moreover, JPEG 2000 is also to support non-lossy compression, as well as other color modes (such as CMYK) and color management. The new standard is scheduled for presentation to the public in the fall of this year.

Kerning

In typography, kerning is the reduction in the spacing between two letters (uppercase and lowercase letters) for esthetic reasons so that the squares they occupy overlap. Typical letter pairs for this are “To” or “Va”.

Laminating

Laminating refers to the general process of covering or coating one type of material with another, creating a firm bond between the two materials. In the postpress stage, laminating is one of the finishing methods used to give the product protection and/or a more attractive appearance. To do this, films containing photographic or other print motifs are applied under pressure to the material being finished. If a transparent polyester film is applied, this is known as film laminating. Laminated materials are often found on drinks and food menus. For packaging liquids, the industry generally uses films that also protect the product’s aroma.

Laser printers

This common type of printer works using a rotating drum, the surface of which conducts electricity when it comes into contact with light. The surface of the drum is first electrically charged. A beam of laser light then records the printing information on the drum line by line by means of a rotating mirror wheel. When light comes into contact with the surface of the drum, it is discharged. The toner which is then applied only adheres to the places that are not illuminated. When transferred onto the paper and fixed in place using heat, the toner produces the print image required.

Letterpress printing

In letterpress printing the elevated sections of a printing form are inked up and, in the printing process, deposit some of the ink on the material to be printed. There are three forms of letterpress printing. In the case of a platen press, one surface presses against another surface; a cylinder press involves a cylinder pressing against a surface; and in rotary printing two cylinders roll against one another. Letterpress printing, the oldest industrial printing process, is used in sheetfed printing for small print runs and special assignments (punching, stamping, perforating, numbering etc.) and also for printing newspapers, although this is now becoming less common. Letterpress printing, in the form of flexographic printing, has been able to hold its own against offset and gravure printing in the area of packaging printing.

Letterset

Letterset is the term for indirect letterpress printing. In this printing method, the ink is transferred from the printing form onto the printing stock via a blanket cylinder without dampening. It is also erroneously referred to as dry offset, which causes confusion with waterless offset printing. Applications of the letterset process include continuous forms and packaging printing.

Lumen

As the unit of luminous flux, 1 lumen (lm - Latin for "light") is the amount of light emitted by a light source with a luminous intensity of 1 candela (cd) into the spheridian unit of 1 steradian (sr - quotient of the superficial content of a segment of a spherical surface and the square of the associated radius of the sphere). Today, the lumen unit is mainly used in a form defined by the American National Standards Institute (the "ANSI lumen"). To this end, the average of the brightness values measured at nine points on an illuminated surface is taken and the luminous flux determined on the basis of a table published by the Institute.

LWC, MWC etc.

Standard international acronyms for weights and grades of papers used in rotary offset and letterpress printing. Coated stock can be termed HWC (heavy-weight coated), MWC (medium-weight coated), LWC (lightweight coated), or ULWC (ultra-lightweight coated). All are woodpulp-based, but available in an array of varieties, including calendered. MFC (machine-finished coated) paper is made primarily from groundwood pulp, has a grammage of 48 to 80 gsm, and may be high volume. LWC paper is particulary lightweight stock for use on rotary offset machines. SC (supercalendered) paper is an uncoated woodpulp stock based mainly on groundwood and recycled content. It features an additional finish applied by a separate supercalender.

Machine proof

The machine proof - also known as a press proof - is used to check the printed result as the outcome of the entire printing process. It is the most complex control tool in the printing process. Its greatest advantage is that it provides a realistic impression of the printed result, independently of the preceding preprint process. Machine proofs come closest to the subsequent printed result when produced on the original paper that is later to be used for the print run.

Machine-finished paper

Machine-finished stock is given its characteristic surface gloss while still inside the paper machine, a process known as calendering. Additional smoothness can be obtained with supercalendering.

Magazine paper

Also called illustration printing paper, magazine paper is uncoated, generally woodpulp-based, calendered stock containing fillers. It is specially suited to the reproduction of graphics and is primarily used to produce magazines using the photogravure process. A stock featuring excellent dimensional stability.

Magnapak

Magnapak is the term given by Heidelberger Druckmaschinen AG to a device used for inserting supplements into newspapers and magazines. The unit can process up to 30,000 copies an hour and can be scaled up to 80 magazine deliveries, i.e. it can insert up to 80 different products. The Magnapak can insert and sort either in sequence or simultaneously, and has been designed without shafts for simple operation and minimal maintenance.

Magnetic printing inks

Magnetic printing inks react to magnetic fields. With the help of suitable sensors, they can be used, for example, for machine-based identification of labels.

Map paper

Map paper is paper with particularly good dimensional stability.

Margins

In the design of a printed page, the free strips between the type area and the page edges are known as margins. According to the position on the page, it is possible to distinguish between the head, foot and side margins and the central gutter. When measuring the margin widths, ratios are often used in typography. The gutter has a value of 2 and the other margin widths in the sequence head – side – foot – are then assigned values in relation to this. For the margin widths, only their ratio to each other is specified – e.g. “2 : 3 : 3 : 4”.

Megabyte

A unit of measurement equal to 1,024 kilobytes, or 1,048,576 bytes.

Microprint

Microprint is extremely small print that only becomes legible when magnified greatly. It is used as a security element on banknotes and other documents at risk of forgery. The image resolution of color copiers, for example, is insufficient to reproduce the microprint.

Mini-book

Mini-books today are generally defined as having covers that are no higher and wider than 7.6 cm (3”) (other definitions relate to the page size or the type area). One of the earliest known printed mini-books from the post-incunabula era is the book of hours produced by Lucantonio Giunta on May 4, 1506 in Venice. The book was entitled “Officium Beatae Mariae Virginis secundum consuetudine romane curie”. It measures just 7.2 x 5.1 cm, is printed on parchment and contains illuminated, full-page woodcuts.

Multimedia

Multimedia is an umbrella term used to describe media products and services which are saved, transmitted and depicted electronically. Important features of multimedia include the shared use of different static (text and image) and dynamic (audio, animation and video) types of media and in the possibility it allows the recipient to use the content interactively. In order to use multimedia, it must be possible to transmit data between the content location and the user in both directions. The video component of multimedia offerings involves large quantities of data which require correspondingly high rates of transmission. Consequently, data storage, transmission and compression technologies play a key role in the development and introduction of multimedia systems. Typical multimedia applications in the private sector include encyclopedia, learning programs and games, primarily in conjunction with CD-ROMs. Popular applications in the commercial sector include teleconference technology and cooperation in technical design work using online links.

Network

A collection of two or more computers and associated devices that are linked together with communications equipment. Once connected, each part of the network can share the software, hardware, and information contained in the other parts.

Non-impact printer

The category of non-impact printers includes all printers which do not exert pressure on the material to be printed. Typical non-impact printers are laser, inkjet and thermal printers.

Oblique

Oblique is the term used for types that slope forwards. This usually serves as a substitute for a non-existent italic version of the typeface in question.

Offset gravure conversion

Offset gravure conversion is a process using screened offset films as originals for the production of gravure printing forms. The particular advantage of this method is that proofs can be made using offset films rather than employing a high-outlay preparation process on a gravure printing press. The fact that the tonal value reproduction of the offset originals corresponds with that of the gravure product makes this possible.

Offset paper

This is a broad term for stock suited to offset printing, covering both uncoated woodfree and woodpulp papers as well as uncoated recycled papers that have been calendered or machine-finished.

Offset printing

The commonly used offset printing method, a lithographic printing process, is based on the different wetting characteristics of the printing and non-printing areas of the printing form. When printing, the lipophile ('oil-friendly') image areas absorb the oil-like printing ink and the blank hydrophile areas repel it. Offset printing works in an indirect way: The printing form transfers the printing image onto a blanket cylinder, which in turn prints onto the paper or other material. There is a distinction between sheetfed offset and web (or rotary) offset printing. The former prints onto paper sheets and the latter onto a paper web.

One-to-one marketing

One-to-one marketing is a term describing activities in the areas of market research, advertising and sales which are directed at individual customers and take account of their individual wishes and preferences. Internet technology, which allows direct interaction with consumers, has made one-to-one marketing possible in markets with large numbers of customers who could only be contacted on a general rather than personal basis in the past. Online dealers can use software which automatically evaluates the behavior of visitors to their web site, and then respond with targeted individual offers.

Onionskin paper

Onionskin is a glazed, woodfree, show-through paper with a grammage of 30 to 39 gsm. White or coloured stocks with grammages of 25.30 or 40 gsm are erroneously termed onionskin.

Opacity

The degree of a paper's resistance to light. Paper printed on both sides must have optimum opacity, a property enhanced by a higher wood content as well as fillers such as kaolin, talcum and titanium dioxide.

Ozalid copy

For a long time, copies produced on dyeline paper, blueprints or ozalid copies (named after the brand name of the paper) were used as proofs for checking the completeness, position and content of printing copy. The basis for this was the diazotype process patented in 1917 by the Benedictine father Gustav Kögel (* 1882 in Munich, † 1945 in Karlsruhe).

Pad printing

Pad printing is an indirect gravure process where a flexible (often semi-spherical) pad of silicon rubber is used as a medium for transferring the ink from the plate to the surface to be printed. This method can be used to print a great diversity of irregularly shaped objects.

Pantone colors

Pantone colors are based on a system of standard colors used worldwide which Pantone, Inc., Carlstadt/New Jersey, originally a printshop, introduced for the graphic arts industry in 1963. The system is based on 512 reference color tones which are mixed from eight basic colors, black and white and are printed on coated and uncoated paper. Today, there are over 1,100 Pantone colors available on a broad range of papers. Pantone has also published color systems for textiles, plastics, paints and film/video.

Paperboard

Paperboard has a grammage higher than paper, but lower than cardboard. A distinction is made between single-layer and multilayer board. In the U.S., often called cover paper.

PDF

PDF is the abbreviation for what is known as the Portable Document Format. Developed by software manufacturer Adobe Systems Inc. in the USA, this data format is used for exchanging and processing electronically stored, formatted documents with text and images, independently of the hardware and software used. One of the special features is that texts and graphics are stored in vector form, meaning that the resolution of their representation is dependently solely on the output device (monitor, printer). PDF files can generally by recognized by the ".pdf" file name suffix. They can be created using the Adobe Acrobat program. The Acrobat Reader is available free for displaying and printing PDF files.

Perfect Binder

Perfect Binder is the name given to a series of automatic book-binding machines from C.P. Bourg S.A., from Ottignies, Belgium. They are also intended to augment digital printing systems, and can be used in conjunction with e.g. the Digimaster 9110 from Heidelberg AG. The maximum throughput for these book-binding machines ranges from 200 to 2000 books per hour. The minimum and maximum dimensions for book covers and book blocks vary depending on the machine type. The maximum book thickness varies between 45 and 60 mm.

Perfecting machine

A perfecting machine generally takes the form of a sheetfed press which prints the sheets on both sides in a single run (recto and verso).

Personalized printing

Personalized printing refers to processes where to a certain degree the individual copies in a print run have distinctive imprints. A minimum requirement for personalized printing is a digital printing process for the individual imprints, which allows the printing data to vary from copy to copy. One common application of this process is the inclusion of the name and/or address of the recipient on the printed product.

Photocomposition

The first fundamentally new typesetting technology since the invention of letterpress printing by Johannes Gutenberg, photocomposition does not use solid forms for depicting the characters. Instead, the set text is created on photographic film. Older machines did this by imaging the characters visually with a flashlight from a negative original (which was generally rotating) or from a very bright screen (cathode ray tube) onto the film. The move to computer setting is marked by the lasersetter which, like the laser printer, uses a laser beam to write the text – but also images and other design elements – directly onto the film or a printing plate

Photoshop

Photoshop, from Adobe Systems Inc., is the leading software package for digital image manipulation in DTP applications. It is available for Macintosh computers and Windows PCs.

Pixel

A pixel – an abbreviation for picture element – is the computer term for an image dot, i.e. the smallest unit of a digitally displayed image. The memory required by an image consisting of pixels is determined by the size of the image, its resolution, i.e. the number of pixels per unit of area, and the number of colors to be displayed.

Pixel format

The format for storing image data where, for a given resolution, every pixel in the image is represented by the appropriate data. Image processing programs such as Photoshop use the pixel format, the most common being TIFF (Tagged Image File Format). The pixel format is most suitable for real images, but, depending on the quality of the image, this requires a very large amount of memory.

Poster paper

Poster paper is uncoated and features special properties that allow it to soften before being posted, facilitate gluing, and add weather resistance. This woodfree, water-resistant, heavily sized stock can remain folded in water for a limited amount of time without loss of print integrity

Postpress

Umbrella term for all processing operations performed on the printed product after the actual printing process, e.g. folding, binding, trimming, packaging.

Postprint

The word "postprint" is an alternative term for "finishing" and encompasses the operations that take place after the print run and result in the finished printed product.

PostScript

PostScript is a page description language developed by the software manufacturer Adobe Systems Inc. which has become a quasi-standard in the digital prepress stage. It describes documents largely independently of the device used, so that for instance the resolution of an image is not defined until the output device. The more recent PostScript 2 offers, among other things, improved colorimetric facilities, since the reference color space is integrated in accordance with the CIE standard. The latest version, PostScript 3, also improves the way in which colors and three-dimensional objects are displayed and supports trapping of graphic objects.

Prepress

Prepress is the term used in the printing and publishing industries for the processes and procedures that occur between the creation of a print layout and the final printing. The prepress procedure includes the manufacture of a printing plate, image carrier or form, ready for mounting on a printing press, as well as the adjustment of images and texts or the creation of a high-quality print file. In today's prepress shop, the form of delivery from the customer is usually electronic, either a PDF or application files created from such programs as Adobe InDesign or QuarkXPress.

Preprint

The word "preprint" is an alternative to "prepress" and covers all the working steps that take place before the actual print run and lead from the starting material to be printed - texts, images, etc. - to the ready printing copy.

Primary colors

Primary colors are the basic colors of a color system, which are used to mix all other renderable color tones. The primary colors are cyan, magenta and yellow (black functions only as an auxiliary color for the technical aspects of printing)in the CMYK system, and red, green and blue in the RGB system.

Primary pulps

The raw materials for paper manufacture, removed from virgin forest products by mechanical means (woodpulp) or a chemical process (chemical pulp).

Printability

Printability covers a range of paper properties affecting print results: gloss, smoothness, whiteness, opacity, etc.

Printing on demand

This term denotes a work process where instead of producing a large print run of a specific product, smaller partial print runs are printed on demand, sometimes only a few copies. Printing on demand has been made possible thanks to digital printing, which allows you to print directly from the prepress data, without having to produce printing forms or set up printing presses.

Program paper

A flabby, generally woodfree paper made from chemical pulp derived from the soft leaves of hardwood trees. Allows noiseless page-turning.

Progressive proofs

When using a proof to check quality, progressive proofs are used to assess the colors on the printing stock. In 4c printing, the four process colors cyan, magenta, yellow and black are printed both alone and in various combinations on a small area.

Proof

A proof is a single print of an original which serves as a definitive means of verifying the layout and color for subsequent printing. In analog proof procedures (Dry-Match, Press-Match etc.) the proof is created from ready imaged films; this largely corresponds to the subsequent printing result. In digital proofing, the page composed on the computer is output on a color printer. This proof is more cost-effective, as it does not require the use of film. However in this case the imaging procedure remains untested.

Pulp

Paper pulp consists of cellulose fibers extracted chemically from plant materials-mainly wood, though annuals as used as well.

PUR binding

The PUR method of binding books and brochures uses polyurethane adhesive. It is processed hot and hardens by cooling. The bond is then impervious to heat. PUR adhesive binding is a particularly high-quality method that is ideal for high-use products such as trade show catalogs and for difficult types of paper.

QuarkXPress

The Quark XPress program is the unchallenged market leader in DTP software for the professional market. The software is available for Macintosh computers and Windows PCs.

RAL colors

RAL colors are standard colors based on a series of color collections for industry which are published by the Deutsches Institut für Gütesicherung und Kennzeichnung, Sankt Augustin (originally "Reichsausschuss für Lieferbedingungen"). All in all, there are over 2,000 RAL colors. The RAL Design System, a color system which takes in the entire color space, contains 1688 color tones. All RAL colors in the RAL Design System and the RAL 840-HR classical color collection are also defined digitally and can be used with all popular graphic arts programs running under Windows and Macintosh and can be used with more than 20 output variants i.e. with different screens and printers.

Raw text

Raw text is a type of text design in which the lines are not made to be of uniform length by correspondingly enlarging the spaces between words. Nevertheless, the available space is put to maximum use by means of word splits. In contrast, deliberately varying line lengths as a creative technique is referred to as ragged setting.

Ream

A unit of measurement for sheets of paper. A ream used to be 480 sheets; in the U.S. the term now refers to 500 sheets or, in the case of a printer's ream,516 sheets.(The German "new" ream refers to 1,000 sheets of paper.)The word can be traced back to the Arabic rizma ("bundle")–a memento of the path travelled by the art of papermaking to reach the Western world.

Recycled paper

Recycled paper is paper which has been produced from 100% used paper. Used paper fibers (also known as secondary fibers) can be used three to five times in this manner. If the recycled paper needs to be pure white, de-inking chemicals have to be used to remove the inks from the used paper, and the fibers also have to undergo a bleaching process. The de-inking process is not used in the production of environmentally-friendly papers, but unprinted white paper has to be used as a raw material in order to achieve a whiteness grade of 40-50%. However, these gray papers have not so far been well accepted by the public.

Redigitization

When print originals in the form of film material are converted back into digital data using scanners and software, the process is termed redigitization. The data can be stored in common file formats and can then undergo further processing using appropriate applications. This method allows a printshop or prepress company to use the scanned films in a digital workflow. Redigitization is often carried out when processing advertisements where the customer has supplied films rather than data as print originals. Three redigitization techniques have become established: Copydot (exact digital copy of the screened original), Descreening and Mixed Mode (a combination of the other two methods). The nature and quality of the original determine which method is the most suitable.

Reel spool

The take-up roll around which the paper web is wound after reaching the end of its journey through the paper machine.

Relaunch

This is when an already existing website goes online with a new face, usually a new navigation structure, new design and increased content for the first time.

Rendering

Rendering is the term used for the realistic representation of three-dimensional models by a computer - on the monitor or in a print. In this context, the object is given the most realistic surface possible, illuminated by a fictitious light source and embedded in an equally three-dimensional environment with light, shadows, reflections, etc.

Resolution

In an optical context, the resolution is a measure of the ability of input and output devices, or of photographic films, to visualize two adjacent dots separately from one another. The resolution depends on the physical properties of the visualizing or recording device or material and is usually limited by the wavelength of the light used. The resolution is usually stated in dots per inch (dpi) or in lines per millimeter.

RGB

RGB is the usual additive color model for the primary colors red, green and blue and is used for self-illuminating output devices such as monitors, but also for electronic recording equipment such as scanners and video cameras. There are a number of different variants of RGB. Hewlett-Packard and Microsoft proposed a new, more uniform standard in 1998 in the form of sRGB.

RIP

The abbreviation RIP stands for Raster Image Processor, which prepares data from the prepress stage for the production of the printing plates. Its most important function is to create screens for printing images and other graphic elements. As a rule, an RIP is a separate computer, but it can also come in the form of software.

RTF

The abbreviation RTF stands for Rich Text Format. It is a data format for texts that contains not only the text itself, but also information on the font, font size and formatting. The Rich Text Format was specified by Microsoft as a software-independent format for formatted texts.

Rub-off

What happens when pressure on stacked sheets causes the ink on one surface to rub off on the next. This "carbon-copy effect" can occur due to the pressure of the clamp in trimming machines.

Running directions

The running direction of paper is the direction it passes through the paper machine, generally the same as the grain direction (direction in which fibers lie). Paper is stiffer and has greater dimensional stability with the grain. The running direction is often indicated by an arrow on sheet packages.

Satellite principle

An offset printing press works according to the satellite principle, where several complete printing units, including plate cylinder, blanket, inking unit and damping unit, are arranged around a central impression cylinder. In this way, all the colors are printed in a single, wet-on-wet process.

Scanner

The scanner is a device for capturing image data which works by optically scanning the original. Light-sensitive sensors convert the information relating to the image brightness and colors into electrical values. The two major types of scanner are the drum scanner and the flatbed scanner. In the case of the former the originals are attached to a transparent drum, and scanning takes place line by line by means of a rotating fine beam of light from the inside of the drum outwards. In the case of the flatbed scanner, the original is placed on a flat glass plate and is scanned from underneath by an array of light-sensitive CCD elements which move across the scanning field.

Screen

In image reproduction terminology, a screen is an area made up of small geometric forms of either regular or random arrangement (e.g. round, square or other shaped dots, lines). The screen is used to convert contone images into a black/white or full-color representation which is suitable for printing. This is done by varying either the size or the frequency of the elements to reflect the brightness of the image.

Screen angle

When screens are regular, the screen angle indicates the angle of the screen from the vertical. When only single colors are used, the screen is generally positioned diagonally (45 or 135 degrees). In multicolor printing, different screen angles should be used for the different colors in order to prevent overlay effects (moiré). DIN 16547 lays down angles of 0, 15, 75 and 45 degrees for the four colors yellow, magenta, cyan and black.

Screen proof

A screen proof is used for advance checking not only of the layout and color information, but also of the screen structures of a print. In this way, faults occurring in this respect, such as moiré and rosette effects, can be detected in good time. As the printing data contain no screen information before screening of the images in the RIP (Raster Image Processor), screening must be performed before printing a screen proof. In order to rule our errors, the proof printer is often controlled by the same RIP that supplies the filmsetter or platesetter with data.

Screen ruling

Screen ruling refers to the number of dots per unit length. Common specifications are l/cm (lines per cm) and lpi (lines per inch). '60 screen' means 60 l/cm and corresponds to approx. 150 lpi.

See-through register

A see-through register is a print element on banknotes that is used to protect against counterfeiting. Parts of a symbol are printed on both sides of the note and only appear as a complete character (letter, number etc.) when the note is held up to the light.

Selective binding

The term “selective binding” describes the personalized production of bound print products from a selection of components. Selective binding can be used, for example, to produce different versions of catalogs where the content is geared to the needs of different customer groups. Selective binding can also be used, for example, when different advertising motifs are required for different issues of magazines.

Semi - fine

Semi-fine stock is paper with a mechanical woodpulp content of more than 5%. The term is usually reserved for uncoated papers; coated stock is more often designated "slightly mechanical".

Serif

A serif is a small stroke on the end of the strokes of letters. This design feature is typical of so-called Roman faces, which can be traced back to ancient Rome. Serifs cater to the perception mechanism of the human eye and thus make type faces easier to read.

Server

Servers are computers or software packages which provide certain services within a network as part of a client/server system. In the prepress sector, high-performance computers are used as data servers to store centrally large amounts of data relating to texts and images in high resolution. Communications servers, which offer data transfer services on the network, play an important role in this field.

Sheetfed offset press

Offset printing is the most popular form of lithographic printing used today and consists of the two variations – sheetfed offset and web offset. Sheetfed offset presses print individual, cut sheets. These presses are subdivided into the following format classes, indicating the maximum format of sheet that can be used: Format class Format 0 500 mm x 700 mm I 560 mm x 830 mm II 610 mm x 860 mm III 650 mm x 965 mm III b 720 mm x 1020 mm IV 780 mm x 1120 mm V 890 mm x 1260 mm VI 1000 mm x 1400 mm VII 1100 mm x 1600 mm X 1400 mm x 2000 mm.

Sizing

The addition of size gives paper ink receptivity as well as other special characteristics. It is usually added to the furnish (the pulp mass)before processing; this is called pulp sizing. Special grades may also be subsequently surfaced-sized on the dry end of the paper machine.

Small caps

"Small caps" is the term used for upper-case letters with a size equal to the basic height of lower-case letters of the type size currently being used. Small caps are used to emphasize individual words in the text.

Spot Color

Spot Color is another term used to describe Special colors.

Stitcher

The stitcher is the name given to the device used for stitching printed products with wire staples. The term is more generally used for gatherer-stitchers, which perform all the processes involved with the manufacture of wire-stitched magazines and brochures, i.e. feeding, gathering, stitching and cutting. Heidelberger Druckmaschinen AG markets stitchers under the name Stitchmaster.

Subtractive color synthesis

Subtractive color synthesis creates a color impression by filtering out individual frequency ranges – i.e. colors – from the overall spectrum of visible light. In the case of color printing, this is done by overprinting the inks – generally the basic colors cyan, magenta and yellow, which can be used to create all color tones of the relevant color space.

Template

A guide for positioning pages or parts of pages consisting of a series of lines to indicate final trim size, bleed, head margin, back margin, type page size, or other elements.

Textured inks

Textured inks create their color impression not (or not only) by means of dyes (pigments), but (also) by their physical structure. They contain special structures - such as thin, transparent flakes - that selectively reflect light of a certain wavelength with the aid of interference effects. Textured inks create shimmering color effects that can vary, depending on the viewing angle. This kind of color generation has its model in nature, where it is found in insects and some species of birds. It cannot be reproduced by conventional means, which is why textured inks are often used for documents that need to be protected against forgery.

Thermochromic printing inks

Thermochromic printing inks change color in line with temperature changes. Depending on the type of ink in question, the color can either change or disappear completely. Some thermochromic inks even react to body heat when touched only briefly. This makes it possible to protect documents against forgery in a readily verifiable manner. Inks that change color at appropriate temperatures are used as temperature indicators for drinks and medicines, or also for monitoring heating and cooling units. Most of the color changes are reversible, although there are also thermochromic printing inks that change color permanently at a certain temperature. When applied to heat-sensitive products, they can indicate potential damage.

TIFF

TIFF (Tagged Image File Format) is a commonly used file format for images. It was defined by a computer industry committee in 1986. It is a so-called screen format that contains information on the brightness and hue of every pixel. The TIFF format supports various color systems, from black-and-white to full-color RGB images. TIFF files can be compressed by a variety of methods.

Tracking system

In logistics, tracking systems are used to provide information on the current status or a query or order, a product in the manufacturing process or a delivery. Very often, these systems form part of an electronic trading system of the type collectively referred to by the term e-commerce. A tracking system, for example, allows a printshop to let its customers follow the progress of their print job via the Internet – from job acceptance to dispatch.

Trim

Trim is the name given to the edge of the page of a printed product that actually extends beyond the planned dimensions of the final product. This trim enables all the pages of a book or magazine to be cut to the same size in the final stage of processing.

Trimming

Trimming a book, brochure or magazine smoothes the edges. Normally three unbound sides are trimmed. In the adhesive binding process, all four sides are trimmed. Trimming also separates the individual pages, so that the book or brochure can be flipped open.

Type 1 and TrueType

Software manufacturer Adobe uses the term Type 1 for a technology it has developed for displaying fonts on monitors and other output devices. The character shapes are defined mathematically (irrespective of size) as curves using cubic Bézier polynomials. A program known as a rasterizer generates the characters as screen images in the required size and suitable for the resolution of the output device.Hints are used to compensate for shortcomings in the display resulting from the limited resolution of the output device. The system also forms part of the Postscript system for defining the graphical form of documents and is therefore prevalent in the prepress industry.TrueType is a similar process that is used for Macintosh computers and the Windows operating system. This technology uses simpler quadratic B-splines for defining the characters. The hints are more detailed than for Type 1. The relevant manufacturers have recently been trying to converge Type 1 and TrueType. As a result, Version 3 of the Postscript system now also supports TrueType technology.

Typesetting

Typesetting involves assembling characters into formatted text for the purpose of producing print originals. Before typesetting machines were invented, text was set by hand using individual letters of type. The first major changeover in the typesetting world came in 1882 when Ottmar Mergenthaler patented the Linotype line composing machine. In the second half of the 20th Century, typesetting moved increasingly towards photocomposition. Today, typesetting and page make-up are largely computerized in the form of “Desktop Publishing".

Typography

Typography is the study of the design and use of type. Its objective is to make text as legible and visually attractive as possible, by choosing appropriate typefaces, font sizes and attributes, but also by means of page layout. The rules of typography for type on paper are so well developed that further improvements scarcely seem likely. However, this is not yet the case for other media such as the screen.

Uncoated paper

Paper without an additional protective coating; "untreated" paper. The application of a colorless coat of glossy or matte varnish as final printing step, either as an overprint varnish applied on-press or a water-based preparation applied by a separate coating machine. Varnishes enhance the appearance of print products and, especially on matte-finished stock, improve the rub resistance of printing inks.

Unicode

Unicode is a method for coding characters for electronic processing and uses 16-digit binary numbers (16-bit numbers). Unlike ASCII and other codes, which work with 8-bit numbers, Unicode is capable of representing 65,536 different characters. This covers all the characters is every commonly used script in the world. Unicode is already in widespread use today.

UV coating

UV coatings (UV stands for ultra-violet) are coating systems based on unsaturated polyesters or polyacrylates, or a combination of the two. For both, ultra-violet light triggers the drying process. This high-energy light breaks chemical bonds in the coating material’s molecules. These then link up to form long, highly-branched chains, causing the material to solidify.The drying process takes only seconds, which means that UV coatings can be worked quickly. These coatings contain no volatile substances either, making the layer thickness of the liquid coating similar to that when it is dry. They can also be applied inline, i.e. in the press, in very high layer thicknesses (up to 8 μm). UV coatings achieve excellent gloss and can be barely distinguished from laminated products (film-lamination). UV coatings, however, are not entirely odor-free.

UV inks

UV inks are printing inks that are cured with ultraviolet (UV)light. For this purpose, these inks do not contain any volatile substances. Rather, in addition to color pigments, they contain individual molecules and short molecular chains that can link to form polymers and so-called photo-initiators. The latter decompose when exposed to UV light and form highly reactive fragments. These radicals trigger a polymerization process in which stable, three-dimensional network structures are formed. UV inks are primarily used to print non-absorbent materials, such as metal (sheet metal) and plastic, but also high-quality paper boards and labels.

Varnish

Varnish or print varnish is a clear coating that can be processed like an ink in (offset) presses. It has a similar composition to ink, but lacks any color pigment.

Waste

Waste consists first and foremost of pages that are incorrectly printed. But it also applies to all waste paper generated in printshops. For example, damaged paper, trial runs when setting up presses, packaging materials and innumerable print products and book returns.

Water-based coating

As their name suggests, water-based coatings – also known as dispersion coatings – are based on water. They dry relatively quickly through the evaporation of the water, are odor-free and do not yellow. Water-based coatings are mainly applied using coating units. In some cases, they are also applied using the press’s inking unit. The layer thickness of the coating can be up to 3 μm. Water-based coatings are not as glossy as UV coatings.

Watermark

Watermarks designs on sheets of paper created by varying paper thickness have been around since the dawn of papermaking. A real watermark occurs when the dandy roll displaces (light watermark) or concentrates (shaded watermark) the pulp mass in the wire section of the paper machine. Facsimile, or impressed, watermarks are made in the paper web after it has left the wire section. Imitation watermarks are added off machine by means of a transparent varnish or embossing process.

Wet on dry printing

Multi colored print process, in which the first Print color is dried before the next colour is printed e.g. color printing on a single color press.

Wet-on-wet printing

Printing in color printing-press with two or more colors. Further colors are printed ever before the previous colours have dried.

Whiteness

Whiteness describes the intensity of white in a paper stock.

Workflow

Workflow is a computer-aided process for organizing work sequences, which consists in systematically moving documents from one stage of the operation to the next. This can only take place if documents are transported within a network or if they are kept in a central location and the individual operations are given access to them at the relevant point in time. Workflow software is able to monitor the work and can, for example, issue an alarm if a deadline is not met.