|
TERM
|
DEFINITION
|
| apron |
White space added to margins of text area on a page to accommodate a foldout. |
| blanket |
In offset litho printing, the rubber-coater sheet that transfers the inked impression from printing plate to paper. In gravure printing, a similar rubber sheet covers the impression cylinder of a printing press. |
| blanket-to-blanket press |
In offset printing, a configuration in which a continuous web of paper is fed between two blanket cylinders, printing both sides at once. Also called a perfecting press. |
| bleed |
Margin outside the trimmed area of a sheet that allows for tints, images, or other matter to print beyond the edge of the page. If sheets are printed without the bleed, it is generally not possible to print matter up to the edge of the page. |
| bottom printing |
Printing on the underside of translucent film or paper, so the design reads through the top. |
| centerfold/spread |
Facing pages in the center of a section. Center spreads are also called naturals. |
| cold-set ink |
A solid ink that, when used on a "hot press" (one that has a heated cylinder), melts into a liquid that then solidifies on contact with the paper. |
| color printing |
Strictly speaking, multicolor printing in inks other than black. However, the term is used more generally describe any printing process that uses colored inks -- including black -- and this encompasses four-color printing. The major printing processes today are offset lithography (either sheet or web-fed) and web gravure. Screen printing is also widely used, although generally for specialist work in small runs. Color letterpress printing -- the oldest method -- has all but died except for very specialist work. |
| die press |
A machine that is used to die cut or emboss a shape into paper or board. |
| die stamping |
A printing technique that uses a die to emboss a relief image onto a surface. Ink or metallic foil is generally used to add color, but if not the surface is said to be blind-stamped. Also known as relief stamping. |
| dye-based ink |
Inks, the colors of which are obtained from alkiline dyes, used mainly for flexographic printing and for screen printing onto textiles. In the latter, dye-based inks are sometimes called "dye pastes." |
| electrostatic printing |
A method of inkless printing using an electrically charged, photosensitive drum or plate that temporarily retains the original image before transferring it to paper using an imaging agent (toner). Typically used for large format printing. |
| gloss ink |
Printing ink usually consisting of a varnish or synthetic resin base and drying oils. Such ink dries quickly, and does not penetrate far into the paper and is normally used on coated and low-absorbency papers. |
| ink |
A fluid comprising solving and oils (called a "medium" or "vehicle") in which a finely ground pigment of plant dyes, minerals, or synthetic dyes is suspended to provide color. There are many different types of inks for the various printing processes. |
| ink transparency |
The degree to which a substrate will show through a printed ink. |
| lay edges |
The two edges of a sheet that are placed flush with the side and front (the "front lay edge") marks ("lay gauges") on a printing machine to make sure the sheet will be removed properly by the grippers and have uniform margins when printed. |
| lay sheet |
The first of many sheets passed through a press to check such things as register. |
| machine proof |
A final ink proof made on a press similar to the one on which it will be printed. Also called a press proof. |
| make-ready |
The process of preparing a printing press before a new run, to establish register, ink density, consistent impression, and so on. |
| off-print |
An article or other part of a publication printed with the main run, but produced as a separate item. Also called a separate. |
| offset |
To reproduce a book by photographing a previously printed edition. |
| offset |
A printing technique in which the ink is transferred from the printing plate to a "blanket" cylinder and then to the paper or material on which it is to be printed. |
| offset blanket |
The rubber-coated blanket used in offset litho printing that transfers the inked imaged from plate to paper. |
| one-up |
A single printing of a single signature or image on a press sheet. |
| pass sheet |
A printed sheet of optimum print quality that is removed from the run, so subsequent sheets can be compared with it. |
| photomechanical |
The preparation of printing plates involving photographic techniques. |
| physical dot gain |
The increase in the size of a halftone dot caused by the spread of ink during printing. |
| plate |
A piece of paper, metal, plastic, or rubber carrying an image to be reproduced using a printing press. |
| plate cylinder |
The cylinder on a printing press onto which the plate is fixed. |
| platemaking |
The process of making an image on a printing plate by whatever means, but usually photomechanically transferring it from film. |
| plugging |
An aberration in platemaking in which dot areas become filled in, caused by damage to the plate. |
| precoated plates |
Litho plates that have received a coating that will not become light-sensitive until they are washed with a sensitizing solution. |
| premake ready |
The final checking of plates before they are made ready on press. |
| preprint |
An item printed in advance of a publication, later inserted loosely into bound copies. Also called a blow-in. |
| press |
Any machine that transfers (prints) an impression, traditionally a from a former block, plate, or blanket onto paper or other material. |
| print |
The image etched, or otherwise generated onto a printing plate. |
| printmaking |
The printing of fine art editions by a variety of processes, such as limited edition screenprints and etchings. |
| production press |
The press used for a printing a job, as opposed to the one used for proofing it; it is generally impractical to use the production press for proofing. |
| register sheet |
A sheet used to obtain correct position and register when printing. |
| roll-to-roll printing |
Rewinding a continuous printed web onto another roll. |
| roll-up |
A check of the first printed sheets to emerge from a press while the plate is still being inked. |
| rotary press |
Any printing press in which the printing surface is on a rotating cylinder. Paper can be delivered to rotary presses in either sheet or web form. |
| single printing |
The process of printing a sheet of paper first on one side and then on the other. |
| spot color |
Any color used for printing that has been "custom mixed" for the job, as opposed to one of the four standard process colors. |
| transfer paper |
The substrate that contains and inked impression that will become the printing form for litho printing. |
| two-up |
A method of printing two copies of each page on a single sheet. They are eventually trimmed into separate entities after binding. |
| vegetable ink |
An ecologically sound printing ink made from vegetable oils. |
| watercolor / water-based inks |
Water-soluble-based, rather than oil based, sometimes used for printing colors from a rubber surface. |
| watercolor printing |
A printing process using water-soluble inks on porous paper that results in the blending of overlapping layers of colors. |
| web (printing) press |
A rotary printing press that uses continuous paper from a large roll that is fed through a series of rollers (cylinders) on which the plates are mounted. The impression from the plate is offset onto a blanket before being printed onto the paper. |
| web offset |
A rotary printing press that uses continuous reel-fed paper "web" where the impression (image) from the plate is offset onto a blanket (usually rubber) before being printed onto the paper. There are three main systems: blanket to blanket; three-cylinder systems; and satellite or planetary systems. |
| wet printing process inks |
Quick-drying inks used in multicolor printing; the last color seals the surface. |
