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Glossary
of frequently used screenprinting terms
Abrade: To roughen a mesh surface yielding
what is termed "tooth".
Accelerator: A chemical additive or modifier used to hasten the drying of
some inks.
Acetate: A plastic material often used in an art department for tracing
designs. In ink form, acetate is used as an opaquing tool.
Adhesive: Any substance used
to hold one material to another. In textile screenprinting, spray, liquid of a
special paper is used to temporarily hold a garment to a pallet during printing.
Other adhesives are used for screenmaking.
Angstrom: Unit of measurement
to express wavelength of light.
Artwork: Original design
intended for reproduction.
Atomization: To reduce to
minute particles of a fine spray.
Biodegradeable: The
susceptibility of a substance to decompose by micro-organisms. Substances that
organically break down into smaller, simple compounds.
Bleeding: The migration of
ink, pigment of dye into unwanted areas. Typically occurs when one ink spreads
or mixes with another ink, forming an unwanted third color. Also can occur
during high-temperature curing where a low opacity ink is placed on a dark
poly/cotton garment red or black, for example. Also known as color migration.
Blend: Describes fabric
content, e.g., 50/50 cotton/polyester, 95/5 cotton/acrylic.
Blisters: Air bubbles trapped
between film and mesh.
Blockout: A solution applied
to screens to keep ink from penetrating. The unblocked, open areas allow ink
through and form the design.
Bonding Agent: An additive
that gives ink better adhesion to such substrates as nylon.
Bridging: Crossing fabric
threads at the edge of a stencil.
Butt-to-butt: One
registration technique where one color is placed against another on a printed
surface. The edges of each color meet exactly, with no overlap.
Camera-ready: Completed
artwork, in color or black and white, that is ready to be photographed for later
placement on screen.
Capillary film: Stencil film
that is adhered to a wet screen via capillary action, filling in the mesh
openings. This is done prior to exposing the screen. Sheet form of direct
emulsion.
Carbon arc lamp: Used to
expose photosensitive emulsions. Because of health hazards associated with these
lamps, other light sources now are more prevalent.
Carrier: A substrate or
backing, usually polyester film, on which emulsion is coated. Indirect,
direct/indirect and capillary films employ a carrier.
Clip art: Camera-ready art
that is not copyrighted and can be purchased from clip art services of is free.
Clogging: Blocking of mesh
opening by foreign matter. See “Scum.”
Coat: To put emulsion onto a
screen.
Cold-peel transfers: A
printing paper with a design, pre-printed with plastisol ink, that is applied to
a garment by heat. The paper is removed after it has cooled. See “Hot-peel
transfer.”
Colorfast: The ability of an
ink to retain its color on a printed garment through laundering, exposure to
light and normal storage.
Color migration: See “bleeding.”
Color Separation: Separating
a multi-color design into it primary color of cyan, yellow, magenta and black.
Individual screen for each color then are prepared, with each color applied
where needed to recreate the full-color design.
Contact printing: A process
in which the entire screen mesh is in contact with the surface of the substrate
being printed upon. See “Off-contact printing.”
Contract printing: Screenprinting
firms that print specific orders for other companies, most of which supply the
garments and camera-ready artwork.
Conveyor dryer: A dryer that
incorporates a conveyor belt that moves garments through a heating chamber.
Sometimes called tunnel dryers. Dryers are generally two types: thermal and
percentage.
Curing: A process typically
associated with plastisol inks whereby temperatures between 280-320 degrees F
(137-165C) are necessary to fuse, or cure the inks.
Darkroom: A light tight room
for photo processing.
Decoating: Stripping stencils
from a screen mesh. See “Reclaiming.”
Definition: Quality of the
edge of the stencil.
Degrease: Removing oils, dirt
and chemicals from a screen before a stencil is applied.
Deposit: The ink design
imprint left on the substrate after printing.
Developing: The process of
converting latent images produced by exposure into visible images.
Diazo: Sensitizer used in
some emulsion systems to cure (fuse) a stencil.
Diffusion: Scattering of
light through emulsion layer of film or through the fabric coated with a
photosensitive emulsion.
Direct emulsion: A liquid
photosensitive chemical coated onto a screen as part of the stencil process, and
exposed after it has dried, while on the screen. See “Indirect emulsion.”
Discharge: The one step
process where special inks that are applied to a substrate most often a black
t-shirt chemically bleach out the substrate’s color and overprint the bleached
area with another color to create a printed image. The process is accelerated
and completed as the garment passes through a curing dryer. Also, the inks that
are used.
Emulsion: Liquid
photosensitive coating.
Extender: A chemical compound
add to ink to increase its volume without changing it viscosity.
Flash cure: A partial curing
(fusing) of plastisol inks.
Flock: Very short individual
fibers that are applied via adhesive to a backing to form a velvety surface.
Fluorescent: Describes
brightly or neon-colored inks, dyes and substrates.
Four-color process: The
process of reproducing a full color design from the original artwork to the
screenprinted surface. Special process color inks, which are transparent are
used. See “Color separation.”
Halftone: A print that is
photographically reproduced using a series of large dots to represent the
varying shades of tones of a design. (In screenprinting, details and dark and
light tones are represented by dots of varying sizes: small dots from light
tones, large dots form darker tones.)
Hand: The feel of ink on a
substrate's surface. A “soft” hand has a light feel; a print with “no”
hand feels like nothing has been placed on the fabric. “Heavy” hand examples
are puff inks and the rubbery-feeling letters on football jerseys. Also, the
weight, heft and fineness of fabric itself.
Heat transfer: The process of
transferring a design from a specially treated paper to a garment using
temperatures around 375F (190C). See “Hot-peel transfer” and “Cold-peel
transfer.”
Hold-down: A device most
often used to hold down nylon and lined jackets firmly to a printing pallet. The
device attaches to the press. Also, a device that holds frames to the press.
Hot-peel transfer: A
specially treated paper with a preprinted design that is transferred onto a
garment via high heat. The paper is removed while still hot. Plastisol ink is
used on the transfer (or release) paper.
Iridescent: Rainbow like
colors that seem to change with direction of light.
Logo or logotype: A style of
lettering of design of a company used as a trademark to identify itself.
Mesh: The woven fabric used
to make screens. Usually composed of synthetic fibers. See “Mesh count.”
Mesh count: The system used
to designate the number of threads per inch in a woven fabric. A high mesh count
means the fabric has smaller holes and is more tightly woven. A low mesh count
means the fabric has larger holes and is more loosely woven. Mesh count affects
design reproduction detail.
Metal-halide lamp: A light
source often used to expose screen stencils. Determined to be a non-harmful
light source. See “Carbon arc lamp.”
Metallic ink: Powdered
metals, such as aluminum and bronze, processed with ink to give appearance of
gold or silver.
Moire: (Pronounced
“mo-ray”) A pattern sometimes caused when two sets of lines of dot patterns
in a process color design overlap, creating an undesirable pattern.
Monochrome: A single color
Monofilament: Screenprinting
fabric woven of single strand material, often polyester or nylon.
Multifilament: A
screenprinting fabric made of two or more strands of material twisted around one
another.
Nap: The raised surface of
pile of a fabric, such as fleece, formed by distressing it.
Non-reproducible color: Certain
colors (fluorescent, for example) that can’t be perfectly color matched in
process-color printing.
Off-contact printing: A
screenprinting technique where the screen is positioned above, rather than
directly on, the surface to be printed. The contact between the screen and the
substrate is made only at those points where the squeegee presses the screen
fabric to the substrate.
Opacity: The quality or
ability of an ink to keep light from penetrating. To completely cover a
substrate, thereby fully hiding the color of the garment underneath.
Overall: Refers to a print
whose image or images cover the entire substrate, front and back.
Oxidizing: The ability of an
ink to dry by absorbing oxygen. To air dry. Many water-base inks can be dried by
this method.
Pallet: A surface that
supports a garment during the printing process. Also called a shirtboard or a
platen.
Plastisol: A family of inks
popularly used by screenprinters. The inks contain a plasticizer, such as
polyvinyl chloride.
Process colors: Primary
printing colors of magenta, cyan, yellow and black that are printed one over
another to produce different hues in a multicolor print. The inks used are
transparent, exhibiting very low opacity. Requires color separations.
Puff ink: An ink that expands
when heated, giving a three-dimensional look.
Reclaim: The process of
cleaning stencils and ink from the screens in order to reuse screens.
Registration: The aligning of
screens using special marking guides or pins to ensure proper color/design
placement and crisp detail on the printed surface.
Reverse: A print in which the
design is formed by applying ink to all but the stenciled artwork, allowing the
unprinted surface of the substrate to form the design as in a photographic
negative.
Scoop coater: A tool used to
coat screen fabrics with photosensitive emulsions.
Scraper: A tool used to coat
screen fabrics with photosensitive emulsions. Also a tool to remove ink from a
screen.
Screen: The combination of
mesh material , stretched over a frame, to which a stencil is attached for
printing. Also refers to the fabric itself.
Scum: The residue of an
emulsion, for example, that clogs the screen mesh, preventing the complete
design from being transferred to substrate.
Self-tensioning frames: Screen
frames that tension the mesh fabric without need for an external stretching
tool.
Solvent: A chemical used to
dissolve or thin screenprinting inks. A substance capable of dissolving another
substance.
Spot curing: The quick,
partial curing of ink.
Squeegee: A tool that forces
the ink through the screen onto the printing surface.
Stencil: That part of the
printing screen that creates the printed image. Can be chemical, photochemical
or paper. A resist.
Step and Repeat: A process in
which a single image is exposed onto a screen several times to give multiple
identical images.
Sublimation: A type of
transfer in which dyes, rather than inks, are used to transfer a design onto a
substrate with a combination of heat and pressure. The dyes vaporize and are
absorbed by polyester fibers. The process can be used to print textiles, as well
as mugs, plates or other specialty items.
Substrate: Anything that is
printed upon.
Tack: The adhesive ability of
a surface.
Temperature tapes: Specially
treated paper used to note the temperature of a dryer. The tapes change color at
specific temperatures.
Tension Meter: A device to
gauge the tautness of the printing screen.
Textiles: Fabrics
Transfer: The process of
transferring by heat a design from a specially treated paper onto a garment.
Plastisol inks and sublimation dyes typically are used.
Translucent: Allowing some
light to pass through.
Transparent: Having the
quality of letting light through, or being seen through. Color process inks are
considered transparent.
Transparent base: Special
kind of gelatin used for thinning the ink so that it has the right consistency
for printing. Also used to make opaque color more transparent.
Turnaround: The time it takes
to do a job from the initial order to customer delivery.
Viscosity: The degree of
fluidity, of flow, of ink.
Wale: The ridge in a fabric
such as corduroy.
Wash-out sink: A large sink
or tub, usually with an adjustable pressure hose, to use as both a cleaning
station for screens and as a preparation area for direct-emulsion-applied
stencils. Also used for reclaiming.
Water-base ink: Inks that
have a water base, as opposed to a petroleum or plastisol bases.
Wet-on wet: Printing one
color over another color before the first color has dried or cured. |
