Printing Glossary

You might be vaguely familiar with screen printing. Perhaps you’ve ordered custom t-shirts or maybe been involved in buying promotional products. But, have you ever wondered about some of the terminology? Does squeegee simply make you think of cleaning windows and serigraphy leave you scratching you head? Worry not, we’ve put together a handy screen printing terms guide. A glossary which will shine a little light on some of the more obscure aspects of the process. Fifth Column are always keen to do that, demystify things, because business is better when everyone is on the same page.

A

Abrader: A screen cleaning agent with small particles which roughen the surface of the mesh to aid capillary adhesion.

.ai: The designation for Adobe Illustrator, a type of image file used in screen printing,.

Air Dry: A term for ink that dries without the use of heat.

All Over Printing: A style of printing that covers all of the t-shirt.

Artwork: A word often used for the design, image, text, and/or logo, that is being printed.

Automatic Press: An automated version of the original manual screen printing press. These machines have a much greater capacity and produce higher quality results.

B

Back Clamps: Sometimes referred to as Rear Clamps. A method of holding the screen in place on a screen printing press with clamps at the back of the print head.

Belt Oven: A machine used to cure printed ink in order to set it on the fabric. It employs infrared panels to heat the ink to 330 degrees Fahrenheit. See also Conveyor Dryer.

Bit Map: Also known as a raster graphic, is another type of image which features in screen printing. A bitmap is a digital image composed of a matrix of dots where, when viewed at 100%, each dot corresponds to an individual pixel.

Bleed: Bleeding is when ink moves outside of the desired area. It can also mean dye from the garment contaminating the ink.

Blend: Blending involves the simultaneous use of two or more inks to create a graduated, blended effect.

Blockout: This is when parts of the screen are blocked, using an emulsion like liquid, so that no ink will be transferred to the material of the garment.

Build Up: A term which refers to the accumulation of ink at the bottom of the screen as printing takes place.

Bulk Printing: Also known as Wholesale Printing. A term which indicates large numbers of garments being ordered. Typically associated with screen printing t-shirts.

Burn: Often known as Burning a Screen, a burn involves exposing an emulsion coated screen to a light source to create a stencil.

Butt Registration: Where two differently coloured sections of artwork meet but do not overlap.

C

Camera Ready Art: The term used in printing when digital artwork is presented as ready to be printed without modification.

Capillary Film: A light sensitive emulsion used to make a screen. When applied to a screen with water, it sticks to the mesh by capillary action.

Carousel: A screen printing press with multiple print heads arranged around a central point. Sometimes called a Rotary Printer.

Catalyst: A substance which helps ink adhere to a fabric, especially with textiles that are more difficult to print.

Cristalina: A small flake of metal (sometimes plastic) suspended in Plastisol ink to achieve a speciality glitter print.

Choking: A method of preventing colours overlapping on the printed design.

Clip Art: Simple artwork, commonly available and often without copyright.

Clogging: Also known as plugging, this occurs when ink dries in the screen and prevents printing.

CMYK: There are two colour modes for print reference: RGB (Red, Green, and Blue) and CMYK (Cyan, Magenta, Yellow and Black). We work in CMYK when producing artwork for screenprinting with attainable colours.

Coating: The application of emulsion to a screen.

Colorfast: When a fabric retains its colour if washed.

Colour Separation: How a full colour image is broken down and separated in order to be printed.

Conveyor Dryer: Sometimes called a Textile Dryer or simply a Dryer. A fixed heat source with a conveyor belt used to cure inks after printing.

Coverage: The quantity of ink applied to a garment when printed through a screen.

Cure: The process of using heat to completely fuse the printed ink. Also known as Drying.

D

Degrease: Cleaning a screen to remove any contaminants before applying emulsion.

Dehaze: The removal of ghost images from a screen.

Discharge Ink: Discharge printing involves adding water-based inks to ‘dischargeable’ dark coloured garments so the dye is removed. Discharge ink works best on dark, 100% cotton and natural fibre garments.

Dot Gain: Where the printed dot is bigger than intended due to the build up of ink on the screen.

DPI: An abbreviation for dots per inch on an image file. In general, a higher number indicates a clearer print. We usually require a 300 dpi file.

DTG: The common abbreviation for Direct to Garment, an alternative form of printing t-shirts and merchandise that is sometimes used instead of screen printing.

Dye Migration: This happens when dye from the garment migrates into the printed ink. A problem which applies to polyester shirts.

Durometer: The hardness of a squeegee which determines the amount of ink which needs to be pushed through the mesh.

E

Emulsion: A light sensitive chemical applied to a screen in order to create a stencil.

EPS: An abbreviation of Encapsulated Postscript. Another image file type.

Exposure: Another term for Burn, the creation of a stencil.

Exposure Calculator: Used to gauge the optimum exposure when creating a screen.

F

Fibrillation: This occurs when the fibres of the garment show through the printed design. It can give the finished article a washed out, faded appearance.

Film Positives: Often called Positives, these consist of an opaque image on a transparent background such as acetate. They are used to obtain the optimum results during the screen exposure process.

Fish Eyes: A defect in the screen (and therefore print) caused by imperfect cleaning of a screen.

Flash Dry: This means to set the ink, dry to the touch, but not completely cure it.

Flashing: A process whereby a white layer of print is applied before colour is printed.

Flood: Filling the screen with ink to push it through the open areas of mesh. This is done using a flood bar in the automated process and a squeegee with manual screen printing.

Flood Bar: The piece of apparatus that floods the screen with ink.

Fluorescent Ink: A specialised ink with the same properties of normal Plastisol ink that are used to achieve much brighter prints.

Four Colour Process: Another term for CMYK, printing with four ink colours (cyan, yellow, magenta, and black).

G

Gap Registration: Aligning artwork so that a gap exists between two different colours.

Garment Finishing: Branding, adding those finishing touches to garments after they are screen printed. These include label removal, re-labelling, custom tags and poly-bagging.

Gel: Partially cured plastisol ink.

Ghost Image: A weak image which can be left on a screen after it has being cleaned and reclaimed.

Glow in the Dark Ink: To achieve a lurid lime green luminous look we mix the ink with phosphors. These are special chemicals that absorb energy and re-emit it as light.

Greyscale: An image without colour that consists of white to black shading.

H

Halftone: An image which consists of variously sized dots. Round dots are the most common, but elliptical and square can also be used.

Hand: The feel of a completed print. You may hear the print referred to as ‘soft hand’.

Heat Gun: A handheld device for curing a print.

I, J, K

Inside Neck Printing: A cost effective printed alternative to woven labels for size and branding, especially on customised t-shirts.

Ink: The printable element used to create a print. Plastisol is the most commonly used ink in screen printing.

Ink Degrader: A solvent used to break down ink prior to a screen being reclaimed.

Ink Well: The side of the screen where ink is placed.

.jpg: Sometimes shown as JPEG, it stands for Joint Photographic Experts Group. This is a widely used image format. They can degrade with manipulation so are not necessarily the first choice for printing. For more detail, click HERE to read our article on image file types for printing t-shirts.

Jumbo Screen: A screen which allows for a larger print area than the standard 28cm x 40cm.

Knocked Out: Parts of the artwork that are left out in a design.

L

Line Art: A black and white image which consists solely of lines without gradations or colour.

Location: The area of a t-shirt or garment to be printed. For example, left chest, centre chest, either side of body and so on. Some designs involve multiple locations.

Logo: A symbol or small design that is used by an individual, organisation or brand to identify itself. Something which is often also used to represent its products and activities.

Loupe: A magnifying glass. Helpful for examining artwork, a print, a screen mesh and so on.

LPI: Stands for lines per inch and is a measurement of printing resolution.

M

Manual Press: A press used in screen printing often utilised in smaller scale t-shirt printing operations.

Mercury Vapour Lamp: A type of lighting unit used to burn/expose screens.

Mesh: The woven material that is stretched over the screen frame and coated with emulsion to make the stencil.

Mesh Count: A number which indicates the size of the openings in the woven thread of the mesh. A higher number means smaller openings and vice-versa.

Metal Halide Lamp: Another form of lighting for burning screens.

Metallic Ink: These plastisol based inks contain metallic particles. Metallic inks, specifically gold and silver, add instant drama and are a popular choice when printing for fashion brands and promo items.

Micro Registration: A way of making very small adjustments to the print head in order to successfully print more precise deigns.

Minimum Order: The smallest number of items that need to be printed for an order to be placed.

Misprint: An error in the screen printed piece of merchandise that is due to the printer.

Moiré: An undesirable pattern which appears in the print. Often caused by elements of the design being incorrectly aligned.

Monofilament: The fabric of a screen, uniform in weave, which is made from single threads.

Mottle: An uneven print, often caused by insufficient ink or an irregular surface being printed.

Multifilament: Screen fabric, less uniform in weave than Mono, woven from multiple threads.

N, O

Newton: The Newton, a unit of force in the SI system, is how screen tension is measured.

Off-Contact: This is the distance between the pallet and the screen, an adjustment in the screen printing process.

Opacity: The capacity of an ink to cover the colour of the item being printed.

Open Area: This refers to the sections of the stencil which allow ink to pass through it.

Outline: The line surrounding the inner fill of another colour.

Outside Diameter: May be shorted to O.D. It means the outside dimensions of the screen frame.

Overcured: Something which occurs when the ink is overheated. Prints can be liable to cracking or appearing faded.

Overexposed: A term for screens which have been burned too long and are consequently difficult to wash out.

Over Printing: Printing one colour over another.

P, Q

Pantone: Also PMS, The Pantone Matching System is a standardised colour matching method. Pantone numbers make it possible for manufacturers, printers and clients to understand and agree on colours.

Pinholes: A defect in a screen which causes very small holes to appear in the stencil after exposure.

.pdf: A document file format which can be used in screen printing.

PFP: A shortening for the term Print-Flash-Print, this is a way to get high quality, high opacity prints on a dark background.

Phosphorescent Ink: Ink which glows in darkness.

Photochromic Ink: Photochromic plastisol screen printing inks change colour in sunlight.

Pigment: That element of the ink which provides the colour.

Pixelated:  Degraded quality in an image where individual pixels are visible to the naked eye.

Plastisol: This is a go-to ink for screen printing that produces bright colours on all fabrics. This sort of ink sits on top of threads instead of soaking into them. They are not water soluble.

Plasticizer: The chemical component in plastisol ink (a suspension of PVC) which makes it flow

Platen: Also known by a number of other terms such as Platten, Pallet and Shirt Board, This is the piece of equipment that holds the garment which is being screen printed.

Platen Adhesive: Adhesive used to hold a garment to the Platen.

POD: Stands for Print on Demand, an ecommerce model of business where garments are printed in direct response to and order.

Point: The standard measurement of font size. Seventy-two points are the equivalent of one inch.

Positives: Another term for Film Positives.

Post-Exposure: Also referred to a Post Hardening, this is a method of improving the durability of a stencil by hardening the emulsion.

Print Approval: A document signed by the client that agrees the precise specification of the job being undertaken by the printer.

Print Head: The part of a screen printing press where the screen is attached.

Print Side: The side of the screen which touches the merchandise being printed.

Proof: Sometimes known as a test print, this is a sample print done before a full run.

.psd: An Adobe Photoshop file image file format (Photo Shop Document) which can be used in screen printing.

Puff: These are unique foaming agents that make your artwork stand out in 3D style. We mix puff additive into plastisol ink and screen print normally.

Puff Additive: The additive for plastisol ink which makes the ink expand in size.

Quartz Lamp: Another form of lamp which can be used in the drying process of screen printing.

R

Raster Image: An image that consists of pixels, a dot matrix data structure.

Reclaiming: An aspect of screen printing whereby screens are cleaned and reused for the next job.

Rear Clamps: A method by which the screen is secured on a screen printing press.

Reducer: Something that is added to screen printing ink to reduce viscosity and therefore make printing easier. 

Reflective Ink: A special pale grey ink that can reflect bright light, similar to car headlights. It is often used for clients wanting hi-vis workwear and sports apparel.

Registration: The name for aligning artwork of different colours.

Registration Mark: The marks used to align separate colours of ink when printing a design with more than one colour.

Resolution: The clarity or quality of an image, often interrupted as the capacity to resolve small detail in screen printing.

Retarder: An additive to ink which slows down the speed of drying or curing.

Retensionable Screen Frames: These are things that stretch the mesh of a frame. Roller frames are a common variety.

Reverse Screen Printing: Sometimes called a push-through, involves printing the inside of a t-shirt.

RIP: Stands for raster image processor, a piece of software which produces a raster image or bitmap.

Rotary Printer: The name for screen printing press which has a separate screen for each colour of the design.

Rub Test: Using a clean white cloth to test for the possibility of migration or bleeding in a print.

Run Off: A design which appears to go beyond the printed surface.

S

Safelight: Lighting best suited to working with light-sensitive material such as emulsion.

Sawtooth: A defect in a stencil which has a step-like appearance.

Scoop Coater: A trough for applying emulsion to a screen.

Scorching: A problem, most common with white shirts, where there is a slight yellowing of garment fibres due to excessive heat.

Screen: Our guide to screen printing terms wouldn’t be complete without mentioning the screen itself. The screen is simply a frame with mesh stretched over it.

Screen Clamps: The things that hold the screen in place.

Screen Opener: A cleaning substance for removing clogged ink from a stencil.

Screen Printing: An ancient method of printing that involves ink pushed through a stencil. Modernised and mechanised, but still essentially the same as it was thousands of years ago.

Screen Stretcher: Something that is used to stretch the mesh of a screen.

Sensitiser: This is an additive that helps emulsion harden.

Separations: The process of creating each colour from finished artwork.

Serigraphy: The term for silk screen printing. Derived from two words. ‘Seri’ which is Latin for silk and ‘graphos’ which is Ancient Greek for writing.

Shirt Board: Another term for Platen or Pallet.

Silk Screen Printing: Another term for screen printing.

Simulated Process: The creation of a photo-like image by printing multiple opaque colours.

Snap-Off: This is an air gap between the bottom of the screen on the print side and the item being printed.

Sodium Metaperiodate: A chemical used in reclaiming the screens used in the screen printing process.

Soft Hand: The feel of a finished print.

Soft Hand Extender: An adjustment to Plastisol ink which gives the print a softer feel. It can reduce the opacity and colour of the ink.

Solvent Based Inks: Acrylic inks such as nylon and polyester.

Spray Adhesive: Typically aerosols, used for holding garments and merchandise in place.

Special Effects Inks: Sometimes called Specialty Inks. A general term for non-Plastisol inks like fluorescent, glow in the dark, metallic, glitter, photochromic etc.

Spread: The addition of an outline to an image to compensate for printing press misregistration.

Spot Colour: Screen printing a stock colour without alteration on wide open areas of the screen mesh. Often used when printing t-shirts.

Squeegee: The blade used in screen printing to push ink through the mesh screen.

Squeegee Angle: This is the angle at which the squeegee is set during a print run. It affects the amount of ink being forced through the mesh.

Static Frame: A type of frame that is fixed without the option to adjust the mesh.

Stencil: The part of the screen through which the image is printed.

Stencil Break Down: A problem where the stencil begins to degrade, usually caused by emulsion failing to adhere or cure properly.

Stirring Stick: Simply a wooden or plastic implement used to stir emulsion.

Stroke: Pushing the ink through the screen (usually with a squeegee). This is similar to flood.

Substrate: The term used for the item that is being screen printed.

Substrate Side: This is the side of the screen that comes into contact with the substrate.

T

Temperature Tape: These are specialised strips that are placed on garments to indicate the temperature as the garment is being dried.

Tension: This refers to how tightly the mesh is stretched on the frame. It is measured in Newtons per square centimetre (N/cm2).

Tension Meter: A piece of equipment which measures screen tension.

Thermochromic Ink: Temperature sensitive compounds that temporarily change colour as the ink warms or cools. They’re effective between -10 and 70°C.

Thickener: Something that is added to ink to increase viscosity and opacity.

Thixotropic: Sometimes referred to as Thixotropy. In screen printing, this relates to the viscosity of ink when stirred. As aspect of Rheology, the study of the flow of matter which is primarily liquid or gas.

.tif: Stands for Tagged Image File Format (you sometimes see it shorted as .tiff). Invented in 1986 by an industry committee in an attempt to standardise computer image usage across multiple platforms. TIF files are high quality.

Tint: The process of adding an extender or white to a colour in order to decrease the strength of that colour.

Tonal Range: The range between the lightest and darkest points in an image.

Trap: A technique which limits the gaps between colours that can come from misregistration.

Tunnel Dryer: Another term for the conveyor dryer used to cure inks after printing.

U

Underbase: Sometimes referred to as Underlay, this is a thin layer of ink (usually white or another light colour) that is printed as the base on a dark garment. The desired colour is then printed on top of this base.

Under Cured: This occurs when the ink on a print has not cured properly. As a consequence, the print will not be permanent.

Undercut: Something which refers to the reduction in size of an image due to light traveling beneath the film positive.

Underexposed: A defect in a stencil caused by it not having enough exposure time.

UV Inks: A variety of ink that cures when exposed to UV light.

V

Vacuum Exposure Unit: A piece of equipment used to obtain the optimum contact between the light source, glass, film, and emulsion.

Vector Graphic: A type of image based on lines and points instead of pixels. It can be resized with minimum loss of integrity.

Vellum: A translucent paper product used in laser printers to produce film positives.

Viscosity: A measure of the thickness or thinness of an ink.

W

Water-Based Inks: Ink made up of water that dyes a garment directly, becoming a part of the fabric, rather than laying on top of a shirt. Water-based prints tend to have a more vintage look to them and can also fade after washing.

Washout: Developing a stencil with water after exposure.

Washout Booth: A unit used for cleaning and reclaiming screens.

Wash Test: As it sounds, this is washing a printed piece of apparel to test that the screen printing is fully cured.

Wet-on-Wet Screen Printing: This technique involves printing layers of ink without curing them between different colours. In effect, the previous layer of ink is still wet when the next is put down.

Wetting Agent: This leaves an even sheet of water on the mesh when rinsed, something which can improve coating ability. It is recommended for capillary films.

Wicking: This happens when ink is drawn into the threads of a printed fabric and gets bigger than the original size.

Wholesale Printing: A term which indicates high volumes of printed garments.

Work Order: A detailed form which is completed after a client submits an order for merchandise to be printed.

And that’s about it for this article. Our guide, glossary, whatever you feel comfortable calling it, for screen printing terms.

Fifth Column have been printing t-shirts here in the UK for decades. When we started out, printing t-shirts by hand and selling them outside gigs, we weren’t too bothered about terminology. However, times change and words matter more than ever in an increasingly complicated and competitive world. Having a handle on what you’re talking about gives you a massive advantage. It makes mistakes less likely and communication far easier.

Everybody wins, and that’s the best basis for any screen printing project.

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