| Dairy label | A label manufactured using a laminate construction which has had the face material and adhesive formulated with the purpose of the labelled container being able to withstand the conditions expected during the product life cycle. |
| Damping | The method used to keep the non printing areas of an offset litho plate free from ink. The damping fluid is a mix of water and chemicals. |
| Damping system | The mechanism in offset lithography for transferring damping solution to the plate during printing. |
| Dancer bar | A control system used at various points along a press to control the feed of material, under tension, into the next unit of the press. Also used to detect web breaks and the condition of the reel of material being fed into the press. |
| Database | Software programmes which permit the mathematical organisation of text and images. |
| Debossed | Text or graphics indented into a surface as part of the design. |
| Deckle | The width of the web on a paper machine. |
| Deflection | Deviation from a straight line under load or rotational speed. |
| Defoamer | A subtance or chemical devised to obviate or remove the tendency for inks to foam or form small bubbles during agitation on the printing press. |
| Delamination | The partial, or complete separation of the layers making up the laminate. May be used to reduce tension, print on the backing, or for other converting requirements. |
| Delayed permanent | Permanent adhesive which when used on a particular surface permits repositioning of the item for a given period prior to the adhesive keying permanently. |
| Densitometer | A device sensitive to the amount of light transmitted or reflected by paper or film substrate. It is used to check the accuracy, and consistency of colour output. |
| Density | The degree of darkness, light absortion or opacity, of a photographic image. |
| Descender | That part of a lower case letter which extends below the main body as in "p". |
| Descreening | Removal of halftone dot patterns during or after scanning printed matter by defocusing the image. |
| Desiccant | A dehydrating agent. |
| Desktop publishing (DTP) | The ability to prepare printable images or pages on a computer for reproduction. DTP began in 1985. |
| Destructable materials | Face materials that break into fragments when removal of an applied label is attempted, ensuring tamper evident properties. |
| Detackification (adhesive kill) | The elimination of the 'tackyness' of the adhesive, either all over the label or just within a specified section. Achieved by overprinting the adhesive with a chemical substance. |
| Dial indicator | A watch-like instrument used to measure, run-out, deflection, etc. |
| Diameter | A straight line passing through the centre of a cylinder or disc and terminated by its boundary. |
| Die adaptor | A device used to modify the die station of a press in order that other sizes of die may be used. |
| Die cut | To cut-out label profiles with a die. Describes a label formed by die cutting. |
| Die cut labels | Self-adhesive labels carried on a backing from which the waste has been removed from around and between each lable. |
| Die cutter unit | The part of the press designed to hold flatbed or rotary cutting dies in a stable position and at the required pressure to perform the cutting action. |
| Die cutting | The action of cutting or bursting through the required number of layers of material in the profile of the required shape. |
| Die key-lines | The die profiles, drawn by hand or computer generated, showing the precise profile of each cut. |
| Die life | The expected linear metres that can be run with a die before it requires sharpening. Due to the fact that there are so many things which can effect die life no standard of expectancy exists. |
| Die pressure gauge | A pressure gauge mounted in the die station which electonically records the amount of pressure being applied to the die at any point in the run. The pressure will vary as press temperature rises during a run. |
| Diecutting unit | The solid unit on the printing press designed to hold the die in position and apply a consistant pressure throughout the run. |
| Dies - air assisted | Rotary cutting/punching tools where the control of any waste is maintained by the use of vacuum and blow. |
| Differential release | A backing material having a release coating on both sides with one being stronger than the other. Used for multi-layer laminates to permit the partial separation of one layer without disturbing the lower ones. |
| Digital colour proof | An off-press colour proof produced from digital data without the need for separation films or plates. |
| Digital halftone | A photgraph or piece of continuous line art that has been scanned and turned into a series of dots by computer controlled equipment ready for printing by one of the conventional processes. |
| Digital plates | Printing plates that can be exposed by lasers or other high energy sources driven by digital data in a platesetter. |
| Digital printing | Printing by plateless imaging systems that are imaged by digital data from pre-press systems. |
| Digitiser | A computer peripheral device that converts an analog signal, images or sound, into a digital signal. |
| Digitized typesetting | The creation of typographic characters and symbols by the arrangement of black-and-white spots called pixels. |
| Dimensional stability | The characteristic of a material which indicates an ability to remain at given dimensions in spite of varying prevailing conditions such as heat or humidity. |
| Direct decoration | The marking of a container by direct printing rather than by applying a pre-printed label. |
| Direct thermal | Substrate coated with a substance which turns black in the immediate areas when heat is applied. |
| Direct to press | The elimination of intermediate film and printing plate stages. Direct transfer of the image to cylinders in the press. |
| Discrete code | A bar code where the spaces between the bars are not part of the code. |
| Dispenser | A device that feeds self-adhesive labels ready for application. |
| Dispensing beak | A realatively sharp edge, of metal, plastic, or card, over which the liner is pulled in order to remove the self-adhesive labels for application. |
| Dispersion | The uniform distribution of solid particles in a vehicle, or liquid. |
| Display type | Type which is larger than the other text matter. |
| Disproportioning (dispro) | The calculated distortion that ensures that a printing plate produced in the flat will print an image of the correct size once it is mounted on a cylindrical roller. |
| Distorsion | The calculated distortion of the plate image in order that it appears correct once wrapped around a cylinder for printing. More applicable to flexo due to the thickness of the plates. |
| Distorted copy | Copy that has been mathematically distorted in order that the image will appear as desired once any shrinkage, or stretching, has taken place. Used especially for shrink-wrap images. |
| Distribution rollers | The rollers on the press which distribute the ink from the duct through to the form rollers. |
| Dithering | A technique used to fill the gap between two pixels with a further pixel in order to smooth out the value of the two or add further detail. |
| Doctor roll | The fountain or metering roll in a flexo press which removes excess ink from the anilox roll. |
| Dot | The indiviual element of half-tones. All the dots in a half-tone have equal density and spacing, but vary in area. |
| Dot etching | Chemically modifying half-tone dots in order to correct colour balance. Dot etching negatives increases colour, dot etching positives reduces colour. |
| Dot gain | The increase in dot size, or shape, between the film stage and the final printed image. This gain can be considerable, 15% or more, and can drastically change the perceived appearance of the colour being printed. |
| Dot matrix printer | A printer that uses a colour coated ribbon and prints bitmapped images (text and graphics). |
| Dots per inch (dpi) | Measurement which refers to resolution, sharpness, or clarity of a printer, a computer monitor, or other output device. 300 dpi = 12 dots per mm. |
| Down-sampling | The reduction in resolution of an image, necessitating a loss in detail. |
| Download | To transfer information from one computer or other electronic device, modem or fax etc., to another. |
| Downloadable fonts | Fonts of type that the operator may install in the printer. |
| Downtime | Non chargable time created by equipment malfunctioning, reel changes, colour changes, etc., or inadequate instructions. |
| Draw-down | A method of checking an ink mix at impression thickness by drawing down a small amount with a pallet knife, meyer rod, or other flat implement |
| Drier | Ink mixing; a substance added to the ink in order to shorten the drying time; The part of a label printing press through which the printed web travels prior to further converting or re-winding. |
| Drive side | That side of the press, usually the back, which houses the main drive mechanism. Also know as the gear side. |
| Dry edge | The edge of the paper or film where there is no adhesive, or a section of a label where the adhesive has been 'killed'. |
| Drying-in | Normally refers to ink drying in the mesh of a screen process stencil. Ink drying between relief dots in tonal printing, or ink drying in reversed out images. |
| Dye test | A test of cutting depth using a green malachite dye mixed in water and spread across the cutting line. The green dye shows up any points where the die cutter has penetrated the silicone coating. |
| Dynamic imbalance | Defect in the cylinder balance on a press such that the cylinder differs in density or balance from one end to the other (see T.I.R.). |
| Dyne | Unit of force (1 dyne = 1g. Per cm second) used to denote the hardness of rubber or polymeric coated rollers. |