Glossary of Digital Print Terms
A
Absorbency
This refers to the amount of liquid or ink substrates or media absorbs. It’s useful to check the absorbency prior to printing to ensure that the print retains its vibrancy.
Additive Colour
This refers to colour produced by light falling onto a surface and is the main type of colour produced by screens and monitors. The additive primary colours are red, green and blue. See also: Subtractive Colour.
Adhesives
In print, adhesives are substances used to stick things firmly together. It’s most commonly used in reference to the adhesive compounds on the back of adhesive vinyl.
Aliasing
This is a visual defect caused by low resolution in a graphic file. If there isn’t enough resolution to reproduce details, jagged lines can appear around the edges.
Anti-aliasing
This is a graphic design technique used to fill in the edges of an object with pixels, eliminating jagged lines and giving it a smoother appearance.
Artwork
This is a general term used to describe graphics which will be printed, comprising images and/or text. This can come via the customer, via a third party or be created in-house.
B
Backlit Graphics
Used commonly in signage and advertising, backlit graphics are printed on a semi-transparent media (known as backlit media) and installed in a light box.
Banner
This refers both to a tough, durable printed product and to the type of media used to produce it. Banner media is often used for large outdoor displays, signs or advertisements.
Bespoke Printing
This term describes a service offered to the client whereby they receive a product designed specifically for their needs. This can require a specific print set-up or additional tools and usually comes at a higher cost.
Bi-directional Alignment
As a print head moves left and right, it will lay down ink in both directions. Bi-directional alignment is a pre-print calibration which ensure that the ink is being applied in the correct place in both directions.
Bitmap Images
Also known as raster images, bitmap images are digital images made up of a grid of dots or pixels. Because of their nature, bitmap images must be of sufficient resolution if they are enlarged. Enlarging a low-resolution bitmap image results in pixelation, whereby the individual pixels become visible creating a blocky appearance. See also: Vector Images.
Blade Offset
This describes the measurement between the point of a cutting blade and the fulcrum about which it swivels inside the blade holder during cutting operations.
Blank
In direct-to-object printing, this refers to a blank item on which print is later applied, and can include items like notepads, USB sticks or mobile phone cases.
Bleed
If a printed product is designed to be cut (as with a sticker, for example), it’s good practice to increase the print area 1-5 mm beyond the boundary of the cutline, thereby decreasing the likelihood of white areas appearing on the finished product. This is known as a bleed area.
Border
This is the space between the printed area and the edge of the media.
Blue-back Paper
This is a common type of media used for advertising and display purposes, which includes an opaque blue backing, designed to block any unwanted previous graphics showing through the media.
C
Calender
A calender (also spelled, calendar) is a device that presses roll-based media between rollers. Calenders are often used to affix laminate films onto printed material.
Calendered vinyl
This describes an economical type of vinyl which has been produced by flattening the vinyl into sheets or rolls using heavy rollers or calenders.
Canvas
This refers to canvas material often used for painting, or textured media designed to replicate a canvas effect.
Capping Station
This is a component in a digital printer which protects and maintains the print head while it’s not in use, by pulling ink through and preventing it from clogging the nozzles.
Cast Vinyl
Cast vinyl is a more expensive type of roll-based media which, unlike calendered vinyl, is formed in a cast, without being flattened by rollers. This is the preferred type of vinyl for wrapping jobs.
Choke
Technique of slightly reducing the size of an image to achieve a desired effect. When printing with a white undercoat, it’s common to choke the boundaries by a small amount to ensure that no white shows around the edges of the image.
CMYK
CMYK stands for cyan, magenta, yellow and black – the four main process colours of digital printing. At the minimum, all digital printers will include at least one channel each for cyan, magenta, yellow and black.
Colorimeter
This is a light sensitive device used for measuring colour in situations where colour accuracy is of high importance, (e.g., printing accurate packaging prototypes).
Colour Bars
Also known as colour control bars, these are test strips which are printed outside of the print area and help to ensure that all colours are printing as expected.
Colour correction
This is the practice of adjusting the settings either in the design or in the RIP to ensure that all colours are represented as expected.
Colour Curves
These are tools in graphic design software which help users adjust the colours of the image.
Colour Gamut
In digital printing, this is the entire range of colours possible which can be produced using a specific device, or ink set.
Colour Matching System
This refers to a colour chart in the RIP used to compare output with expected results and assist with design (e.g. Pantone or Roland Color System Library).
Composition
In graphic design, this refers to the arrangement of type, graphics and other elements on the printed product.
Contrast
This refers to the difference between darker and lighter tones in an image, ranging from highlights to shadows.
Crop Marks
If a printed product needs to be trimmed before completion, crop marks are included to indicate where the cuts should be made.
Crop
In graphics software, or in the RIP, it’s possible to decrease the amount of an image to be printed by cropping it either horizontally or vertically, effectively removing the cropped areas.
Cure
With certain ink technologies, a period of curing is required, during which the inks dry and residual gasses are released. See also: Outgassing.
Cut and Print
This is an alternative to print and cut in which the substrate is first cut, before ink is applied. This is usually employed in cases where the media may be affected by the ink, as with very thin films.
Cutting Die
See: Die
Cutting Force
This describes a cutting plotter’s ability to cut through tougher types of media.
Cyan
One of the four main process colours. See also: CMYK.
D
Debossing
This is the process of stamping the media or paper so that an image or portion of the design is recessed into the surface. See also: Embossing.
Densitometer
This is a device used to measure the density of ink and maintain consistency between different printing devices. Compared to colourimeters, densitometers are cheaper and easier to use, making them ideal for print professionals who need to maintain consistency, but don’t need exact colour matching.
Die
This is a metal plate used to cut a shape or impress a design into a substrate, usually paper.
Die Cutting
A process of cutting material using metal dies in specific shapes. In digital print, this process has been made cheaper, faster and more flexible using print-and-cut technology.
Direct-to-film Printing (DTF)
A form of transfer printing in which ink is delivered to a special film, then fixed to an item (usually fabric) with the aid of a heat press.
Direct-to-garment Printing (DTG)
A form of garment printing in which ink is printed directly to fabric (usually treated with a primer solution), then affixed with heat.
Direct-to-object Printing (DTO)
This describes any process by which ink is printed directly onto the surface of an object.
Dot
This refers to the individual elements of a digitally printed image.
Dot Size
This refers to the size of a dot on the substrate once the ink droplet has been delivered.
Dots Per Inch (DPI)
Also called pixels per inch (PPI), This measurement defines the resolution of a printed image by the number of dots that fit horizontally and vertically into one inch – sharper images will have a higher DPI.
Doubling
This is a printing defect where an image appears blurred. In digital print, this is usually caused by incorrect bi-directional alignment or poor media gap adjustment.
Dummy
See: Mock Up.
Dye-Sublimation
This is a special print technology in which high temperatures are used to change the colour of the substrate, rather than simply applying ink on top of it.
E
Eco-solvent Ink
A more advanced form of solvent ink which offers the same flexibility of older solvent inks with a much lower VOC content. See also: Solvent Ink.
Embossing
This is the process of stamping the media or paper so that an image or portion of the design bulges out from the surface. See also: Debossing.
Encapsulated Postscript (EPS)
This is a graphics file format containing both images and PostScript commands. Abbreviated EPS file.
F
Fast Colour Inks
This refers to inks which retain their colour density and resist fading as the product is washed and used.
Fifth Colour
In digital print, this refers to an additional colour used besides CMYK to increase the colour gamut.
Finish
This refers to the surface qualities of a particular media, including dull and glossy, or smooth and textured finishes.
Finished Size
This is the final size of a print product once all trimming and folding has been completed.
Finishing
This refers to all steps which must be completed after the printing has been done and can include trimming, laminating or installing in a roll-up banner.
Flatbed
A format of print hardware in which an object or substrate is placed on a flat surface, while a print head moves over it on a gantry system.
Flock Vinyl
This is a type of thick HTV which has a soft, fabric-like texture, frequently used for producing custom clothing.
Fogging Back
This is the practice of lowering the density (i.e., lowering the opacity, or increasing the transparency) of an image so that any superimposed text will be more legible.
Foil
A thin film of metal which is applied to a product using foil stamping, foil embossing, laser foiling or UV foiling.
Four-colour Process Printing
This is a technique of printing that uses cyan, magenta, yellow and black (CMYK) to reproduce full-colour images. See also: CMYK.
Frosted Vinyl
Also known as etched vinyl, this is commonly used for producing window graphics with the aid of a cutting plotter.
G
Generic Distance Mode
This is a special print mode for direct-to-object printing which greatly improves print quality on curved or uneven items by delivering smaller ink droplets.
Gloss
This refers to the finish of a substrate or media having a reflective, shiny appearance.
Gloss Ink
This is a special type of transparent ink used in digital printing which is used to highlight areas of a printed design with a reflective, glossy overcoat. It is can also be built up in layers to create a tangible texture, or to create Braille lettering.
H
Head Strike
This is a roll-to-roll printer error whereby the media lifts from the base enough for the print head to impact it during printing. Head strikes have the potential to destroy print heads, so it’s best to avoid them at all costs.
Heat-transfer Vinyl (HTV)
A type of media which can be fixed to an object (usually a garment) with a heat press. HTV comes in many forms, either as solid colour, patterned, textured, or as a blank media on which ink can be printed.
High-fidelity Colour
This is a term used to describe colour produced using additional colours besides the typical CMYK ink set.
HLS
In graphic design software, this is an abbreviation for hue, lightness, saturation, a method of colour control.
Hue
A specific colour such as yellow or blue.
I
Impact Printing
This is a specialist form of printing, similar to engraving, in which details are imprinted onto the surface of a metal item, using thousands of microscopic punch-marks.
Ink Set
Also known as inkset or ink configuration, this describes the ink channels available in a specific device, for example, an ink set of CMYKLcLMLkWh will include cyan, magenta, yellow, black, light cyan, light magenta, light black, and white.
Inkjet Printing
This is a term used to describe a form of printing by spraying droplets of ink through computer-controlled nozzles.
J
Jig
This is a specialist unit used in direct-to-object flatbed printing which can contain multiple similar items, spaced at regular intervals, facilitating faster set-up.
JPEG
Also known as JPG, this is a type of raster image file.
K
K
Abbreviation for black in four-colour process printing. K refers to ‘Key’ or ‘Key Plate’, a term from manual printing processes, meaning the registration plate to which the other plates (C, M and Y) are aligned.
Kerning
In typography, this is the process of adjusting the space between characters to achieve a more aesthetically pleasing result.
Kiss Cut
To cut the top layer, but not the backing layer, of self-adhesive vinyl.
L
Laminate
A thin transparent film applied to a print, creating a glossy effect and providing protection against water, abrasion or UV light.
Latex ink
A water-based ink, favoured for applications which require low emissions of VOCs. See also: Resin Ink.
Leading
In typography, this is the amount of space between lines of text.
Light Colours
This refers to additional colours besides CMYK which are added to the ink set. They usually include light cyan (Lc), light magenta (Lm) and light black (Lk) and they are used to help create smoother gradients, particularly useful when replicating skin tones.
Loupe
This is a lens built into a small stand used to inspect prints.
M
Magenta
One of the four main process colours. See also: CMYK.
Margin
This refers to the space around the edge of printed material.
Mask
In graphic design, this is the practice of isolating parts of an image so they can be treated in some way without affecting the rest of the image (e.g., applying a black and white effect to a background whilst keeping the subject in full colour).
Matte Finish
This is a flat (not glossy) finish on a substrate.
Media Gap Adjustment
This is a pre-print calibration which ensures that the best quality print will be delivered depending on the thickness of the media in use. This should be performed each time a different type of media is installed in the printer.
Metallic Ink
This is a special type of ink made with powdered metal or pigments that create a metallic effect when printed.
Metallic Media
This is a category of roll-based media which simulates a metal effect. It comprises a variety of shades (e.g., gold, silver, brass), finishes (e.g., brushed) and uses (e.g. adhesive vinyl, heat-transfer vinyl).
Mil
This is an imperial measurement equal to 1/1000 inch and is often used to express the thickness of films and other roll-based media. Similar measurements in metric are usually expressed in micrometres or µm.
Misting
Generally speaking, the print head should be sufficiently close to the substrate to generate a crisp and clear result. At greater distances, misting occurs as the particles of ink spread out in transit, resulting in a blurry, unfocused print. Special measures can be employed to mitigate this effect. See: Generic Distance Mode.
Mock Up
Also called a dummy, mock ups are pre-production examples of a print product created for approval before committing to a full print run. In certain cases, digital mock ups can also be used at an earlier stage with the help of graphic design software to identify issues prior to production.
N
Nesting
This is the practice of grouping multiple jobs together in a print run to maximise the use of the material. This can be done manually in the design stage, or via an automatic functionality in the RIP.
Nozzle
A component in a print head which delivers microscopic droplets of ink accurately.
O
Opacity
This generally refers to the ability of an object or substance to block light. In digital print, the quality of white ink is usually determined by its opacity.
Outgassing
In solvent or eco-solvent printing, the ink pigments are absorbed into the material, while the solvents evaporate in a process called outgassing. It’s best to wait until the outgassing period has elapsed before applying any additional laminating film.
Outsourcing
The practice of sending elements of a job, which cannot be completed in-house, to a third party. While this increases the capabilities of a business, outsourced work has an impact on production costs.
Overprint
To print one image over a previously printed image, such as printing CMYK ink over white ink, or gloss ink details over an image printed with CMYK.
P
Pad Printing
Also called tampography, this is a method of mass-printing in which a 2D image is transferred, via a flexible silicon pad, to a 3D object. Though it is good for printing large volumes, it is not appropriate for producing customised short runs.
Pantone Colour
This is one of the main colour-matching systems used by printers and graphic designers. Most brands will express their brand colours in Pantone colours in their brand guidelines if the colour is intended for print.
This is an abbreviation of portable document format, a file format which saves image and text and is commonly used with RIP platforms.
Perforated Cut
This is a form of digital cutting in which both the top layer of media and the backing sheet are cut, leaving small tabs to keep the cut elements attached during production. It’s often used as a term to describe cutting through the entire media, as opposed to using a kiss cut.
Pica
This is an imperial measurement equal to 1/6 inch and is often used to express the size of text on a printed product. A pica contains 12 points.
Pixel
Short for ‘picture element’, this describes a dot composing a digital image. See also: Raster Image.
Pixels Per Inch (PPI)
See: Dots-per-inch (DPI).
PNG
This is a type of raster image file – it’s popular in uses where transparent areas are required.
Prefeed Operation
This is a command which allows the user to feed out the amount of roll-based media prior to commencing the print operation, and it helps ensure that there is enough media on the roll to complete the job.
Primer Ink
This is a special type of printable primer which can be printed with precision like any other ink, and enables durable printing on difficult substrates like glass or stainless steel.
Print and Cut
This describes the ability to print onto a substrate (usually rolls of adhesive vinyl media), then cut accurate outlines in the same operation, with the same device.
Print Head
A component in a printer which houses print nozzles and controls the delivery of ink to the substrate.
Print Then Cut
This describes a practice in which graphics are first printed on one device, then with the aid of registration marks, they are cut with a separate device. This method is preferred when a secondary lamination step is required before the media is cut.
Process Colours
This refers to the four fundamental colours, cyan, magenta, yellow and black (CMYK) which are used in digital printing to produce full-spectrum colour. See also: CMYK.
R
Raster image
See: Bitmap Image.
Raster Image Processor (RIP)
This is a piece of software which translates a digital image into instructions which a digital print device can interpret. Besides this basic functionality, several RIPs contain additional features which assist operators with their workflow (e.g., nesting, job grouping, etc.).
Registration Marks
Also known as register marks, these are used during a print-then-cut operation to instruct a separate cutting plotter where cuts should be made on a printed sheet or roll.
Resin Ink
A water-based ink which is a more advanced alternative to latex ink, offering greater stretchability and more vibrant colours, whilst offering the same low VOC content.
Resolution
Refers to the number of pixels an image contains and is expressed in pixels per inch (PPI) or dots per inch (DPI). See also: Dots Per Inch (DPI).
Return to Origin
In several print operations, this is an instruction which the operator can give in the RIP, which tells the printer to return to the point at which the print started.
RGB
This refers to red, green and blue - the additive primary colours used rendering colours in screens and monitors.
Rich Black
This is a darker and deeper black colour which is produced by combining other ink colours with black ink (usually 40% Cyan, 30% Magenta, 30% Yellow, 100% Black).
Roll-to-roll
A format of print hardware in which a roll of media is fed through while a print head moves left and right delivering ink, or a cutting blade performs accurate cuts.
S
Scale
The process of enlarging or reducing an image is known as ‘scaling up’ or ‘scaling down’ and is usually expressed as a percentage of the original size.
Scoring
Also known as creasing, this is the process of pressing a sheet of paper, card or other media to create a groove or line for easier, more accurate folding.
Scratch Resistance
This describes the degree to which a finished product can resist scratches or other damage, either due to durable ink technology, or a scratchproof coating or laminate.
Screen Printing
This is an analogue method of printing where ink is pressed through a fine mesh to produce an image. A separate screen is required for each ink colour, which limits the ability to produce short runs, however this is a popular method for producing high volumes of printed goods at high speed.
Solvent Evaporation
See: Outgassing.
Solvent Ink
These inks contain pigments suspended in an oil or alcohol carrier, in comparison to aqueous inks which have pigments suspended in water. See also: Eco-solvent Ink.
Spectrophotometer
This is an instrument used to measure the refractive index of colour.
Spot Colour
Rather than mixing CMYK inks to replicate a specific colour, spot colours are premixed inks with their own dedicated channel. See also: High-fidelity Colour
Spot Varnish
This is the practice of applying a glossy varnish to highlight a specific area of the print, rather than varnishing the entire print. In digital print, this can be easily replicated with gloss ink.
Sublimation
See: Dye Sublimation.
Substrate
A substrate is any surface or medium to which ink is applied.
Subtractive Colour
This refers to colour produced by light reflected from a surface, as with printed material. See also: Additive Colour.
T
Tagged Image File Format (.TIFF)
This is an image file format used for storing high resolution images.
Take-up Unit
On roll-to-roll devices, this system collects printed material and feeds it onto a roll, to keep it protected during long print runs.
Telescoping
When a roll of media is not installed perfectly straight in the printer, it unrolls unevenly creating a telescope shape, and can cause head strikes if not fixed.
Texture
This describes the way a surface feels when touched. In digital printing, it can refer to the finish of a substrate, the surface of an item or a simulated texture printed with gloss UV ink.
Throughput
A term describing the amount of material which can pass through a system in a given time, for example, the amount of printed material a printer can produce in an hour.
Tiling
When printing graphics wider than the maximum print width (e.g, large wall graphics), this RIP functionality lets operators accurately split the graphics into several panels.
Transfer Printing
This describes any process by which ink is first printed onto a film, plate or pad, before being transferred to another surface.
U
UV Printing
Also known as UV LED printing, this is a print technology whereby a special UV ink is applied to the substrate, then it is instantly cured with ultraviolet (UV) light.
V
Variable Data Printing (VDP)
A more efficient approach to printing large quantities of individualised items in a single operation, without having to configure custom details on each item.
Variable Dot Size
Compared to fixed dot size printing, this is an innovative approach to ink delivery which allows for printing droplets of varying sizes. This results in more crisp details and more solid fills whilst maintaining the finish of the media.
Varnish
This is a clear liquid coating applied to a printed product for protection and to add a glossy appearance. In digital print, varnish effects can be replicated with gloss UV ink.
Vector Images
These are digital images made up of lines, curves and points positioned in relation to one another. Due to their nature, vector images can be scaled up without impacting the image resolution and they are the preferred format for logos, icons and non-photographic images.
Vignette
This is a decorative design effect where the image gradually fades to white towards the edges.
VOC
Abbreviation for volatile organic compounds, petroleum substances used as the vehicles for many printing inks.
W
Waste
Unusable paper or paper damage during normal makeready, printing or binding operations, as compared to spoilage. Planned spoilage.
Waterslide
This is a transfer printing process in which graphics are printed onto a special thin film, then separated from the backing by submerging in water, before being slid into place onto the item. This is most commonly seen in printed decals for model making.
Weeding
This is the process by which excess vinyl is removed following a cut job.
White Ink
This is a specially formulated type of ink commonly used as a base coat when printing on dark or transparent substrates.
Wiper Blade
This is a component in a digital printer which wipes excess ink from the print head to prevent it from clogging the nozzles while the printer is not in use.
Wrapping
This is a specialist skill whereby graphics are printed onto adhesive vinyl, which is then ‘wrapped’ around a 3D surface. Wrapping is most commonly used for customising vehicles.