Ll

l
abreviation for metric unit of capacity.

label
an applied printed identification denoting contents, ownership, directions, destination, rating, or use.

label adhesion test
a method to determining the degree that a standard or designated label adhesive adheres to a surface under specific conditions.

label, face cut
refer to face cut label.

label, laid on (label, die cut)
die cut pressure sensitive labels on a release liner or backing where the matrix has been removed.

label, pressure sensitive (label, self-adhesive)
any label manufactured from a pressure sensitive substrate.

label, punched out
labels that have been die cut through both the face and backing sheet or liner.

label, roll
labels produced on continuous strips and packaged in continuous roll form.

label, sheet
labels that have been produced in sheet form.

labels, split top (butt label; knife-cut label)
labels so located on the sheet that one edge abutts the comparable edge of another so that one edge of the die separates the labels in cutting.

label stock, pressure sensitive (self-adhesive label stock)
pressure sensitive substrate material suitable for the production of labels.

label, tamper proof
pressure sensitive label material where removal after application is not possible without destroying the label.

label tarnish proof
pressure sensitive labels that are free of substances that might discolor or blemish copper or silver.

label transparent
pressure sensitive labels whose face material, adhesive and protective coatings transmit light so that objects may be seen through them.

lacquer
any of various clear or colored synthetic coatings made by dissolving nitrocellulose or other cellulose derivatives together with plasticizers and pigments in a mixture of volitale solvents used to impart a high gloss to a surface.

lacquer diluent
a fast dry strong solvency diluent used in lacquers and synthetic coating.

lacquered paper
paper that has been coated with a lacquer or plastic.

lacquer stencil
a photo-sensitive lacquer-like material laminated to a temporary support sheet.

lacquer thinner
blended solvent made up of a mixture of tolulen, alcohol, ester, glycol ether and other solvents.

lag
the momentary time of contact of the printing screen to the substrate immediately after the printing stroke.

laid finish
paper with a pattern of parallel lines at equal distances giving a ribbed effect.

lake
a pigment made up of organic coloring matter with an inorganic base or carrier.

laminant
adhesive used for combining and bonding films, foils, plastics, papers or other material in sheet or web form.

laminate
(1) the act of adhere a film to a surface by hand or mechanical means to form a single multi-layer sheet; (2) a web or sheet material formed by bonding materials together.

laminating film
usually a clear or transparent sheeting manufactured for use as a protective top strata of a cold seal or thermal lamination to processed material.

laminating press
a device for producing a multi-layered sheet or for applying a protective sheet of clear plastic to a printed sheet or liner with pressure and heat or just pressure.

lamination
a sheet of material composed of two or more layers of material adhered together to form the sheet such as a liner and face material together with an adhesive to form a sheet of pressure sensitive label stock.

laminar flow
air flow where essentially the entire body of air within a confined area moves with uniform velocity and direction as the ambient atmosphere being sampled.

laminator
refer to laminating press.

lamp
a light source.

lampblack
a gray or black material made from soot obtained from the incomplete combustion of carbonaceous material used as a pigment to achieve a dull black ink with softer, grayer top tones and bluer undertones.

landscape
a page that has a greater width than height; page layout in horizonal format.

lenox cut
a continuous and precise sheeting method in which revolving steel disc slitters cut sides and rotating blades cut ends, for ream to ream accuracy of 0.397mm or 1/64 inch.

lap easel
an easel providing a rest for slanted lower parts of displays.

lap marks
the slight ridge produced by overlapping of colors, found especially in glass decorating where screen printed films are thicker than in usual commercial screen printing.

lap register
refer to lapping colors.

lapping colors
over-printing of the edges or other portions of the area of a printed color by a succeeding color.

laps
non-printed or blank space on edges of printed billboard poster paper used for joining and matching multiple sheets.

large-format
a printer, media, or print 24" or greater in width.

laser
a high energy single wavelength pin-point light.

laser scanner
a device that uses color filters and beams of light to produce tone and color corrected separations for process printing.

latent curing
the use of a curing agent that is stable at room temperatures, but promotes a rapid cure at higher temperatures.

latent charge
electrostatic printing, the charge remaining in the area not exposed to light and dissapated.

latent image
invisible image on exposed film that has not been developed.

lateral reversal
left to right or mirror image reversal.

layout
(1) a guide showing the arrangement and location of all type, illustrations, line art drawings, or sketches of a proposed printed piece; (2) the floor plan view of a printing plant or manufacturing area.

lays
the fixed guides used to register a substrate on the printing bed.

laysides
the two sides of a sheet set against register guides (lays) for registration during screen printing.

lazy flame
a type of flame resulting from a gas rich mixutre.

lb
abbreviation for pound.

LC
abbreviation for lethal concentration.

lc
abbreviation for lowercase.

LCD
acroynm for liquid crystal display.

LD
acroynm for laser diode; abbreviation for lethal dose.

L/D ratio
relationship between an extrusion screw length and its diameter.

LDPE
acroynm for low density polyethylene.

LE
acroynm for low elogation.

leachate
liquid, including any suspended components in a liquid, that has percolated through or drained from hazardous waste.

lead dryers
chemical combinations of lead with various organic acids that are used to accelerate the drying of screen printed ink film.

lead-free ink
inks and coatings formulated for special purposes that contain less than 0.06% lead by weight measurement (US).

lead glass
glass containing a substantial portion of lead oxide (PbO).

leading edge squeegee
the corner of the squeegee blade that contacts the mesh during the printing stroke.

leafing
a phenomenon where metallic pigments form a layer parallel to the surface of the substrate, yielding a high metallic luster.

lean
a color and oil mixture, that does not flow easily and smoothly on application.

lean mixture
a type of flame resulting from an air/gas mixture where too much air is present.

least-square lines
in statistical computations, the straight line for which the sum of the squares of the residuals (deviations) is minimized.

leather hard
clay that is dry enough to hold its shape, but damp enough to work with tools.

LED
acroynm for light emitting diode.

ledger paper
a durable grade of business papers generally used for record keeping.

legend
characters, nomenclature, text, type and/or symbols to be printed.

legging
the stringing out of pressure sensitive adhesive when a material is drawn away from a substrate, its release liner, or its matrix.

lehr
a long tunnel shaped conveyorized oven for annealing and firing ceramic ink.

LEL
acroynm for lower exsposure limit.

length
the flow characteristics of a screen ink, often referred to as "long" or "short," but more often a screen ink will be short.

leno weave
a locking-type weave of silk bolting cloth that has twisted strands running in one direction with each twist encasing a single strand running in the crosswise direction; prevents the shifting of fibers in an open weave.

lens
one or more pieces of optical glass designed to collect and focus rays of light to form a sharp image on light-sensitive film, paper, or projection screen.

lens aperture
the adjustable opening in the iris diaphragm of a camera that determines the amount of light that will pass through the lens during exposure.

lens axis
an imaginary line drawn through the center of a lens from the front of the lens through the rear element.

lens board
support that holds the lens in alignment with optical axis of a camera and allows it to move along that axis in connection with the reproduction percentage adjustment.

lens speed
the largest lens opening (smallest f-number) possible for a specific lens. (A fast lens transmits more light by way of a larger opening than a slow lens).

lenticular
a grooved plastic sheet with certain light properties that give a different visual angle at different light angles, creating a 3-dimensional effect when printed.

letter A easel
a version of the figure four easel that has the cross link located in a very low position.

letter guide
an adjustable mechanical lettering tool operated manually to produce lettering from guides, or templates.

letterpress printing
a process where ink is applied to paper or other substrate by means of relief (raised above the non-image areas) printing plate or type.

letterscreen
in printed circuit board manufacturing, a printing screen produced specifically for printing nomenclature.

letterset
refer to dry offset.

levelling
(1) process used to manufacture metal frames that are level across the frame dimension; (2) the smoothing out of a color application after it has been applied.

levy screen (crossline or contact screen
a glass or plastic screen with very fine cross hatching rulings used for translating continuous tones into halftones.

Lexan®
registered trademark of General Electric (GE) for polycarbonate film.

LIFO
acroynm for last in, first out.

lift
a group of sheets cut or trimmed together.

lifting
the softening and penetration of a paint or ink layer by another ink film, the solvents of which cause wrinkling or raising of the first layer.

lift transfer
a technique for making positives where an image printed on clay-coated paper is separated from the paper and transferred to a transparent or translucent plastic sheet.

ligature
letters that are joined together as a single unit of type such as fi, fl.

light
electromagnetic energy in the 380 to 750 wavelength that affects vision.

light bug
a round light sensing device with a cord attached for connecting to a radiometer for measuring UV light intensity.

light emitting diode (LED)
a semiconductor device that emits incoherent light.

light emitting diode display
type of electronic changeable copy sign that uses hundreds of light emitting diodes in single and tri-color matrixes.

light integrator
an instrument used when exposing photo sensitive materials that measures the intensity and duration of a light source

light intensity
brightness of a light source, equal to the function of the power of the source over a designated distance.

light meter (exposure meter)
a device for measuring the light reflected from a subject, or in some cases, also measuring the intensity of light falling on the subject.

light reflectance value
the amount of light reflected by a given color. (Yellow has a higherlight reflectance value than purple).

light scatter
refer to halation.

light sensing units
a device capable of converting the energy of any light striking its surface to electrical or mechanical energy.

light source
aside from the sun, any device capable of converting electrical, mechanical, or chemical energy into a light-emitting form.

light-source geometry
the effective increasing of undercutting angle that occurs as the light source gets closer to the copy.

light stability
a measure of the ability of a pigment, dye, or other surface material to retain original color and physical properties, with extended exposure to sunlight or other light sources.

light struck
photosensitive materials accidentally exposed to light because of incorrect handling methods or because of light leaks in the camera or darkroom.

light table
a table with built-in lights under a ground glass (or similar) top used for spotting negatives, opaquing positives, tracing, examining, making overlays, and cutting of stencil film.

light trap
a passage into or out of a photographic darkroom, usually composed of overlapping portions or revolving shields that do not permit the passage of light rays from the outside.

lightfast
the capability of a material, coating, or ink to resist fading when exposed to sunlight or artificial lighting.

lightness
equals value of color; perception by which objects are distinguished from gray objects and light from dark objects.

lightweight
a class of fabric made of 26 or 28 single yarn.

lightweight paper
book grade paper of basis weight 40# or less with high opacity.

lim
abbreviation for limit.

lime glass
glass containing substantial quantities of lime, unusally associated with soda and silica.

lime crown glass
an optical crown glass containing substantial quantities of calcium oxide.

limit switch
electromechanical device used to control travel distance.

limited coordinates specification
a specification or standard issued to cover the need for requirements unique to one particular department, primarily found in military documents.

LIN
abbreviation for linear.

line art
single color diagram or drawing usually black and white with no intermediate grayscale.

line conversion
a method of changing a continuous tone image into a line illustration with bold, dark areas on a light background with no intermediate tones.

line copy
any type, design, drawing that can be reproduced without using a halftone screen.

line count
the number of lines of halftone dots per centimeter or linear inch.

line drawing
artwork, originals or printed matter consisting of lines or solids or dark and light tones.

line dropping
subsampling to reduce the number of raster lines in an image by dropping every nth raster line from the scan. See also pixel dropping.

line gauge
a ruler scaled in picas and points, but may also include inches and agate measurements, used by printers.

line image
a photographic image that is composed of fine, solid lines or dots or other shapes, all solid black or color, with no graduations of tones as in a continuous tone image.

line replication
creating more raster lines than are actually scanned by replicating every nth raster line from the scan. See also pixel replication.

line shot
an exposure, made in a camera, of line art copy or larger solid areas that are not graduated in tones.

line speed
the rate of travel of a substrate through a production line such as a drying or curing line.

line tone
a form of halftone made up of parallel lines instead of dots.

line width
the actual width of a screen printed line measured very accurately and precisely in mils; also refer to conductor width.

linear
related to a line, measurement involving a single dimension not square or cubic.

linearity
(1) the closeness of a calibration curve to a specified straight line. Non-linearity is expressed as the maximum deviation of any calibration point on a specified straight line during any one calibration cycle; (2) the degree to which the input of a signal is proportional to the output.

linen tester
a small magnifier mounted at a distance above its base equal to the focal length of the lens; also refer to loupe.

liner, release
the component of pressure sensitive stock that functions as a carrier for the face sheet.

lines
(1) thin markings denoting the contour of a design; (2) parallel rows of halftone dots.

lines per centimeter (LPC)
the number of dots per centimeter. (As a general rule the higher the dot count per centimeter, the higher the resolution).

lines per inch (LPI)
the number of dots per inch. (As a general rule the higher the dot count per inch, the higher the resolution).

lining
face sheet or cardboard stock where the face or surface material differs from the center core laminations.

lining gold (lining palladium; lining platinum)
royal metal compositions suitable for lining on glass or ceramic ware.

linkage
the connections or links between various components of a motion display and the display motor.

linoleates
generally, the salts or soaps of linseed fatty acid. (Cobalt, lead and manganese linoleates are widely used in drier compositions for inks).

linseed oil
a yellowish oil extracted from flaxseeds used as a drying oil in printing ink.

lint
(1) cotton fibers, usually loose on the surface of textile goods; (2) any small unintended foreign substance trapped in the first or second surfaces of a print and visible by sight or feel; (3) paper dust loose on the surface of paper products; (4) clinging bits of fuzz.

lipophilic
refer to hydrophobic.

liquefy
to convert or be converted from a solid form to a liquid.

liquid bright gold
a complex organic resinate of colloidal gold, fluxes, organic resins, and organic solvents suitable for application to glass or china, where high temperature firing develops a bright mirror finish.

liquid chromatography
a chromographic process for analyzing liquids and solutions where the moving phase is a liquid.

liquid crystals
thermochromic, micro-encapsulated materials that react to changes in temperature by changing color, and which may be added to screen printable clear coating.

liquid crystal display (LCD)
type of electronic changeable copy sign using liquid crystals that become opaque or clear when exposed to a controlled voltage.

liquid frisket
a water-soluble latex solution that becomes water-insoluble when dry, used in the preparation of resist stencils.

liquor ratio
the amount of water used in a dyeing process.

lisle
generic name for two ply fabric.

liter
metric standard measure of capacity equal to the volume occupied by one kilogram of water at 4ºC and at the standard atmosphere pressure of 700 millimiters; equal to 0.9463 US liquid quarts.

litho
abbreviation for lithographic or lithography.

litho film
a high contrast photographic film.

lithographic paper (litho paper)
paper that has been coated at least on one side to make it suitable for lithographic printing.

lithography
a method of printing by the planographic process using a coated plate whose image areas attract ink and whose non-image areas repel ink.

lithol red
a relatively brillant moderately lightfast organic red pigment with shades from orange to deep maroon, derived from a dystuff by treatment with metallic salts. (Lithol is a registered trademark of BSAF).

lithol rubine
a bluish red pigment used for process red (magenta) ink. (Lithol is a registered trademark of BSAF).

livering
an irreversible increase in the body of inks as a result of gelation or chemical reaction during storage; also refer to flocculation.

load
(1) the total force applied to a substrate in testing for compression resistance and tensile strength; (2) the electrical demand of a process expressed as power (watts), current (amps) or resistance (ohms).

load capacity
the maximum amount of weight (load) that a device, instrument, piece of equipment, etc., can support without causing excessive wear or damage to the device. (Load capacity can be specified in either a horizontal or vertical plane depending on the configuration of the specific device).

load deflection curve
curve where the increasing flexural loads are plotted on the ordinate axis and deflection caused by those loads are plotted on the abcissae axis.

lock
a device used in display construction that is designed to attach two or more parts; to hold parts in position more or less rigidly; to secure an angle or position of one or more parts in set-up.

lock stitch
a tack down stitch formed by three or four consecutive stitches of at least a 10 point movement.

loft
the relative ability of fibers to return to their original dimensions after being compressed.

logotype
name of a company or product in a design used as a trademark or identifier in advertising.

long
describes ink that has good flow characteristics; also refer to length.

long grain
paper made with the machine direction of the fibers in the longest dimension of the sheet.

long ton
a unit of weight equal to 2,240 pounds avoirdupois.

long-wave infrared
wavelengths greater than 4 microns within the infrared spectrum.

look-through
the appearance of paper when viewed by transmitted light, disclosing the texture of the sheet.

loom
a machine for weaving mesh or fabric from two series of yarns or threads crossing at right angles.

loop tack tester
instrument used to measure the tackiness of flexible pressure sensitive adhesives by determining the force required to break a bond formed when the adhesive is brought into contact with a test surface.

looping
an eratic stitch construction resulting in loops on the surface of the embroidery.

loose register
in the screen printing of multiple colors, occurs when the registration of one to the other is not considered critical or exact.

lossless compression
a compression technique that will retain all of the file's original image characteristics. The perfect lossless compression technique remains elusive.

lossy compression
a compression technique that will sacrifice some image quality at low levels and continue to degrade more image quality as compression levels increase.

lot number
a control number assigned to a material by the manufacturer to track specifics on when and how it was made.

loupe
an adjustable-focus magnifier incorporating a precise measuring scale, with or without a self-contained light source, for inspecting fine detail; also sometimes spelled lupe.

low carbon hot oil
thermoplastic vehicles that burn out easily.

low elongation mesh
screen mesh made from a specially formulated polyester known as LE that has greater stability and can be streched to higher tensions.

low-energy dyes
dyes that require relatively low transfer temperatures (usually under 191ûC or 375û F) to effect sublimation.

lower case
uncapitalized letters of the alphabet.

lower exposure limit (LEL)
the lowest concentration of gas or vaper (% by volume in air which will burn or expolde if an ignition source is present.

low key
a photograph or other image whose tonal range is mostly in the shadow regions.

low tack adhesive
an adhesive with an initial non-aggressive character for ease of application that usually becomes a more permanent bond after 24 hours or other pre-selected time period.

lpc
acroynm for lines per centimeter.

lpi
acroynm for lines per inch.

LSE
acroynm for low surface engergy.

lumen
a unit of measure for the flow of light.

luminescence
a phenomena of light emission by a chemical composition which is film-forming and which absorbs light, releasing it when extraneous light sources have been removed; a "glow-in-the-dark" capability.

luminous reflectivity
when specifying a color, it is the ratio of the luminosity of the specimen to that of a standard reflector under identical conditions.

lupe
from the German word for magnifying glass, refer to loupe.

luster
a solution of organic pigments modified with suitable oils, resins, and solvents that are fired to produce an iridescent surface appearance on the ware.

LUTS
Look-Up Tables: A digital processing method to modify data from the input to the output, by using an array of data from a stored table.

lux
(1) a metric unit of illumination; (2) the amount of illumination produced by a light source of one candela intensity on a surface one meter or 3.28 ft distant (lux x 0.00929 equals foot candle); a unit used to define the illumination falling on a surface.

lux second
unit of exposure expressed in the metric system for illumination; equivalent to that produced by the illumination intensity of 1 candela at a distance of 1 meter for 1 second. (English equivalent is footcandle/second).

luxometer
photoelectric device used to control the duration of camera exposure according to actinic light and fluctuation of camera lamps.

LZW
The Lempel-Ziv-Welch image compression technique.

Back to Top