| A |
| Abrasion resistance of ink | Is typically testet by using a fine sand paper while applying a head force of 4 Newton on the sand paper and doing 200 grinding movements forwards and backwards on top of the printed image. |
| Absorbing materials | Paper, carton are absorbing materials. Plastics are non-absorbing materials. |
| Adast printing presses | A manufacturer of printing presses located in the Czech Republic. |
| Adhesion of ink | Describes the level of intermolecular binding forces between ink and plastic material. In the card printing industry, it is tested by an adhesive tape which will be sticked on the print and then peeled off rapidly. The ink will remain on top of the card surface when the quality is ok. |
| Anilox technology | Describes the ink transfer from the ink casstte into the roller system via an anilox roller which
shows laser engraved nips of a constant nip depth and diameter on its surface. Excess of ink
on the anilox roller surface by rotating through the ink is wiped off by a blade. The advantage is a constant ink quantity transfer, the disadvantage is the unflexibility when more or less ink will be needed during the printing process.
|
| Anti-static bar | Reduces the electrostatic and dyne level on plastic surfaces which improves the transport through the machine and the adhesion of ink on the plasitic substrate. |
| Anti-toning agent | Consists of silicone oil and reduces the scumming effects of the inks. Recommended quantity to be mixed into the inks up to max. 5% |
| Anti-tack paste (=reducer) | Reduces the ink viscosity in order to improve printability of the ink. Usually can be added up to 5% to the ink. Note that too much reducer used in waterless offset will result in scumming. |
| C |
| Cast coated | Coated paper, dried under pressure against a polished cylinder to produce a high gloss finish. |
| Conti-Air | A german manufacturer of blankets for the printing industry. |
| Continuous tone image | A photographic image which has not been screened and contains gradient tones, eg. a normal photograph. |
| Card materials | Typical card materials are ABS, PVC, PET, PC, carton.(...see our product list ) |
| Cartridge paper | A strong, stable compressed paper with natural, uncoated surface. |
| Catching-up | In lithography a term which indicates that the non-image areas of a press plate are starting to take ink or scum. |
| Chip cavity | A cavity considered in the card according to chip or microprocessor shape and dimension. |
| CMYK | The four process colours used in offset printing: cyan, magenta, yellow and black. |
| Coated paper | Paper with a surface coating which produces a smooth, glossy finish. |
| Coating | In plate making: the light-sensitive mixture applied to a metal plate. In printing: an emulsion, varnish or lacquer applied over a printed surface to give added protection or gloss. |
| Cold colour | In terms of printing, a colour which is on the blueish side.
|
| Colour correction | Changing the colours of pixels in an image to achieve the desired effect. |
| Contrast | The difference between the lightest and darkest areas of an image. |
| Cooling system for offset presses | In modern sheet offset presses there are watercooled vibration rollers and plate cylinders to avoid scumming. Depending on heat transmission of the press and the used inks it is recommendable to adjust water temperature in a range of 20 - 28 °C ( 68 - 82 °F ).
It is also possible to use chilled air which blows on the printing plate .
|
| Corona treatment | Improves dramatically the dyne level of plastic sheet/card surfaces and consequently the ahesion of inks on the plastic substrate. This process should be integrated into the press to take the max. advantage. The effect of corona treatment is reversible and remains effective a few days. |
| Cromalin | Actual colour proof for customer´s and printer´s reference. |
| D |
| Density range | The range from the smallest highlight dot to the largest shadow dot. |
| Die-stamping | A printing process using an engraved, intaglio (depressed) image and producing an embossed, relief effect on the substrate. |
| Digital proofing | Producing page proofs directly from stored digital information without film or plates, eg. laser, inkjet, thermal transfer dye sublimation or ink-jet systems. |
| Dummy | A model of the printed product produced prior to publication to show, as far as possible, the size, shape and major features as a guide to production. |
| Duotone | The reproduction of a black and white picture in two colours, normally black and another colour. One colour tends to stress the highlight areas and the other the shadow. |
| Density of ink | The ability of an object to stop or absorb light. The less the light is reflected, the higher its density, eg a solid black area on film reflects no light and therefore has 100% density.
Standard densitometer values of CYMK in Offset printing are:
- Yellow : 0.8 – 1.0
- Cyan : 1.4 – 1.5
- Magenta: 1.4 – 1.5
- Black : 1.7 – 1.9
|
| Densitometer | An instrument used to measure the density of a given area or screen, eg. 50% |
| Die-cutting | The use of sharp steel rules to cut special shapes from printed sheets. |
| Dot gain | Is the difference of original dot size on the film/plate and the real printed dot on the sheet/card. Wet-offset on absorbing materials shows higher dot gain than waterless offset. Non-absorbing materials like PVC show even better results. Moreover, dot gain can happen if the pressure of the blanket to the substrate is too high.
(... see more details ) |
| Double sheet control system | Control device to make sure that only one sheet/card at a time enters the printing press in order to avoid a damage of the blanket. |
| Duplicating | Describes a printing error and shows often double lines around shape or edge lines. Reason is very often a too high pressure between printing plate and blanket. |
| Dyne level of plastic cards | Is an attribute which mainly determines the adhesion of the ink on the plastic surface. It is measured in mN/m and acceptable levels are 38 mN/m or higher in order to obtain a good adhesion of ink. It can be checked with test-pens prior to printing. .( ...see our product list ) |
| G |
| Gradient fill | A fill that displays a gradual transition from the foreground to the background colour. |
| Gripper edge | The leading edge of paper as it passes through a printing press. |
| Gutter | The blank space or margin, from printing area to trim. |
| Ghosting | Describes a printing error when a part of an image reappears as a shadow at a place on the sheet/card where it should not be. Mostly, this happens in images where there are white areas within a solid (100%) print area. A well working solution is to change the settings of the vibration rollers by changing length and begin of linear movement relative to the plate cylinder. |
| Gloss varnish | Is often used to cover/protect printed images. |
| Grain | The direction in which most fibres line, which corresponds with the direction in which the paper is made. |
| Grammage | The weight in grams per square metre of paper, expressed as gsm. |
| Grey scale | A strip of standard grey tones ranging from white to black, placed at the side of an original during photography to measure range and contrast. |
| Gripper margin | The unprintable blank edge of paper in which the grippers bear. |
| H |
| Highlight | The lightest part of an image in a halftone represented by the area with the smallest dots or no dots at all. |
| Hairline register | Register within ½ - row of dots. |
| Halftone | The reproduction of a continuous tone image, which replaces contone with a stream that breaks the image into various dot sizes. |
| Heidelberger printing presses | The most famous printing press manufacturer worldwide. Headquarter in Wiesloch, Germany. |
| Hickeys | Spots or imperfections in printing due to dirt on the press, dried ink, paper particles, etc. |
| Hickey picker | A soft rubber (silicone) roller which picks dirt off the printing plate. |
| Hollow dots | Uncorrectly printed dots which lost ink in the center of the dot. Possible reason is the usage of a too hard ink. |
| M |
| MAN Roland Printing Presses | A worldwide leading german printing machine manufacturer. |
| Manifold | A thin strong, uncoated paper used for business forms and documents, where low bulk is required |
| Midtone | The tonal value of dots located approximately between the highlight and shadow values |
| Make-ready | All work done prior to printing on a press – adjusting the feeder, grippers, side guide and putting ink in the fountain or duct. |
| Moiree pattern | An undesirable pattern in colour printing, resulting from incorrect angles being used on overprinting colours or reproducing from an already printed subject |
| P |
| Perfecting press | A printing press that prints both sides of the paper in one pass |
| Pixel | A single dot on a computer display or in a digital image. A Pixel as such does not have a dimension. The actual size of the Pixel is depending on the measure DPI of the screen or any other ouput medium. |
| Point | A traditional standard of type measurement (12 points is equal to ± 4mm) |
| Pressure-sensitive paper | Material with an adhesive coating protected by a backing sheet until used, which will stick without moistening. |
| Progressive proofs | Proofs made from the separate plates in colour process work, showing the sequence of printing and the result after each additional colour has been applied. |
| Pantone | An international system of matching colour for printing, designating unique colours by standard numbers |
| Positive | A piece of film with an image in which dark areas appear solid and light areas appear transparent. |
| Postscript | A coding language intended for output devices |
| Ppi / PPI | (pixels per inch) a measure of the density of scanned information in an image. The finer the optics and detector of the scanner, the higher the scan resolution. |
| Presstek | Manufacturer of the first CTP-waterless offset printing plate which is not necessary to be developed. |
| Printing plate | A plate consisting of an aluminum base covered by a photoreactive layer which reflects one individual colour of a multi-colour image after film exposing. It is mounted on the plate cylinder in a printing press. |
| Process colours | The four process colour inks used in printing – cyan, magenta, yellow and black. |
| Proof | A visual interpretation of an image to be printed |
| S |
| Screen ruling | The number of dots per inch or cm. Also known as screen frequency |
| Set-off | The unwanted transfer of ink from a substrate to parts of the press or other parts of the substrate, etc. |
| Sheet work | To print one side of a sheet of paper, and then turn the sheet over and print the other side |
| Shadow | The darkest part of an image, represented by the area with the largest dots
|
| Sharpen | The process of increasing the contrast at specific points in a photographic image where lighter and darker areas touch. |
| Sharpness | The ability to reproduce minute details of an original. The sharpness is related to the resolution of a photograph. The sharpness of a digital image can be manipulated artificially in a wide range by digital image processing. |
| Soft dot | A type of dot whose density is not high enough, with the edges being thinner. This will create a fuzzy or flat picture in the plate-making and printing process. |
| Stochastic | A type of positive, and a method used to achieve colours where the trouble of eliminating moiré patterns is minimised. This method still uses dots but they are generated in a random frequency and position. |
| Scanner | An electronic device that digitises and converts photographs, slides and paper images into bitmapped images |
| Screen angles | The angles at which halftone screens are positioned in relation to one another to avoid moiré patterns..
The set of angles most commonly used are:
- Cyan = 105°
- Magenta = 75°
- Yellow = 90°
- Black = 45°
|
| Scumming | An undesireable effect showing ink spots on originally white areas of the image. This happens if the printing plate is not able to separate the ink effectively from non-printing areas of the plate. Reasons are mostly a too high machine temperature, too high ink volume, too low ink viscosity or wrong adjustment of rollers.
In wet offset process, the reason is very often a wrong balance of dampening and inking volume. |
| T |
| Tiff / TIFF | (tagged image file format) a file format used to represent black and white, grey scale or colour bitmapped images, particularly those produced by scanners. |
| Tint | A flat even tone area of a colour. |
| Trap | An overlap that prevents gaps from appearing along edges of an object or flat colour area in a separated image which would otherwise appear due to paper stretch or slight misalignment of a printing press. |
| Toray Industries, Inc., Graphic Systems Department | The lone manufacturer of waterless offset printing plates worldwide, located in Japan. (except CTP-plates) |
Company, brand or product names used here are copyrighted by the particular companies and organizations.
