K:

(1) Abbreviation for black in four-color process printing. (2) Amperes per square centimeter divided by volts per centimeter. The reciprocal of resistivity.

Kanji:

Chinese characters introduced to Japan in the 5th century by way of Korea. Kanji are ideograms. Every single character corresponds to a word.

Kauri Butaonl (KB) Value:

A measure of the solvency of a hydrocarbon solvent. Values range for 20 (poor) to 100 (excellent).

Kelvin (K):

Unit of measurement for color temperature. The Kelvin scale starts from absolute zero, which is -273 degrees Celsius.

Ketones:

A class of organic solvents used for vinyl type inks and often used in reducing Type C and Type T inks, e.g., acetone, methyl ethyl ketone, methyl iso butyl ketone.

Key:

Color separator's and printer's name for the black plate of a four-color reproduction.

Kiss die cut:

To cut the top layer of a pressure-sensitive sheet and not the backing.

Kiss Impression:

Lightest possible impression that will transfer ink to a sunstrate.

Knockout:

An area on a printer's spot-color overlay in which the overlapping color is deleted so the background color shows through.

Kodachrome™:

A type of color transparency manufactured by Eastman Kodak.

Kodacolor™:

A colored negative manufactured by Eastman Kodak having dye couplers of complementary colors, i.e., a green dye in the negative corresponding to a red dye in the positive print material.

Kraft:

A sulfate wood pulp paper made from unbleached bleached or colored wood pulp by the sulfate process. Kraft papers have a coarser finish than wovens and are noted for their strength. Most commonly used in the manufacture of catalogues and booklet envelopes.

LAB (Luminance And Brightness):

A system for describing, measuring, and controlling color, using hue, luminance, and brightness established by the International Committee on Illumination (CIE).

A - B - C - D - E - F - G - H - I - J - K - L

M - N - O - P - Q - R - S - T - U - V - W - X Y Z

L*C*H:

A color space that is similar to CIELAB, that uses cylindrical coordinates of lightness, chroma, and hue angle instead of rectangular coordinates.

Lacquer:

Clear varnish with a plastic film former base (originally used to denote nitrocellulose-type fast-drying inks and varnishes).

Lacquer Stations:

Any unit used to apply overprints.

Lamella:

A blade angle etched or ground to a thinner gauge than the base thickness of the blade stock.

Laminate:

A product made by bonding together multiple layers of material, usually united with an adhesive or extruded polyethylene.

Lampblack:

A carbon black pigment prepared by the incomplete combustion of vegetable oils, petroleum, or asphalt materials; used to achieve a dull, black ink.

LAN (Local Area Network):

The linking of workstations, storage units (file servers), printout devices (print servers) via broadband cable for high-speed simultaneous communication

Land Area:

The unengraved area of a gravure cylinder, upon which the doctor blade rides. Tops of cell walls as well as un-engraved areas are included.

Landscape:

Artist style in which width is greater than height. (Portrait is opposite.)

Lap:

An area where one color overprints another adjacent color, usually held to a fine line, but which can vary considerably depending upon the press equipment and the effect created by overprinting two or more colors.

Lapping:

Rubbing two surfaces together, with or without abrasives, for the purpose of obtaining extreme dimensional accuracy or superior surface finish. The final polishing of gravure cylinders both in copper and chromium is akin to a lapping operation.

Laser Engraving:

The application of image information directly onto a zinc layer by the thermal energy of a pulsating laser beam. Every laser pulse creates one cell by local evaporation of the zinc material. Because of the pulse repetition rate of the laser beam, 70,000 cells per second can be generated.

Laser Printing:

Similar to a photocopy machine, the laser printer uses a laser beam, toner, and fuser to "etch" the image onto a photoelectric drum.

Lateral Adjustment:

Move blade toward or away from cylinder; also, parallel blade to cylinder.

Lay Edge:

The edge of a sheet of paper feeding into a press.

Lay Flat Bind:

Method of perfect binding that allows a publication to lie fully open. (Also known as Lay Flat Perfect Binding.)

Layout:

A sample of the original providing (showing) position of printed work (direction, instructions) needed and desired.

Leading:

Amount of space between lines of type.

Leaf:

One sheet of paper in a publication. Each side of a leaf is one page.

LEL:

The Lower Explosive Limit of a solvent vapor-the lowest concentration of a combustible solvent vapor or gas in air that will produce a flash of fire if ignited. Mixtures below this concentration are too lean to burn.

LFL:

Lower Flammable Limit, similar to LEL.

Length:

The property of an ink whereby it can be stretched out into a long thread without breaking; long inks exhibit good flow characteristics.

Letterpress:

A method of printing that uses a relief plate as an image carrier. The image area of the plate, raised above the nonprinting area, receives ink from rollers, and transfers it directly to the substrate being printed.

Letterpress Inks:

These inks are of moderate tack and viscosity. Each type of printing press requires an ink having a different combination of properties. For example, cylinder press ink must be longer and less tacky than platen press inks, but shorter and tackier than rotary press inks. Most letterpress inks dry by oxidation. These are also letterpress inks that dry by penetration (news inks), by evaporation (heat-set inks) and by precipitation (moisture or steam-set inks).

Leveling Action:

The ability of a plating solution to produce a surface smoother than the substrate of basis metal.

LFL:

Lower flammable limit, similar to LEL.

Light:

Electromagnetic radiation in the spectral range detectable by the human eye (approx. 380 to 720nm).

Lightfastness:

The resistance of printed or colored material to the action of sunlight or artificial light.

Lightness

The attribute of visual perception in accordance with which an area appears to emit or reflect more or less light. Also refers to the perception by which white objects are distinguished from gray objects and light-from dark-colored objects.

Light Source:

An object that emits light or radiant energy to which the human eye is sensitive. The emission of a light source can be described by the relative amount of energy emitted at each wavelength in the visible spectrum, thus defining the source as an illuminant. The emission also may be described in terms of its correlated color temperature.

Lightweight Paper:

Book paper with basis weight less than 40# (60 gsm).

Lignins:

A family of polymers that binds cellulose together in plants. Colored yellow in their natural state, they darken noticeably under heat or chemical action. Lignins are removed during pulping and bleaching.

Limited Current Density:

(1.) Cathodic: the maximum current density at which satisfactory deposits can be obtained. (2.) Anodic: the maximum current density at which the anode behaves normally, without excessive polarization.

Linearization

A specific type of calibration where an output device is adjusted to deliver a straight-line relationship between input and output.

Line Copy:

Any high-contrast image, including type, as compared to continuous-tone copy. Also called line art and line work.

Line Negative:

A contrast negative of type or line art.

Line Screen:

A number used to express the fineness of a halftone screen, ranging from 25 to 300 or more lines per linear inch. The number refers to the number of dots such a screen is capable of producing in a single row exactly one-inch long.

Linework:

Line art can be a line drawing or text. Either one can be tinted as percentages of process color or made a solid value such as black text. Abbreviated as LW.

Link:

In desktop publishing, it refers to reference information within a document or to joining text boxes so that text will flow from box-to-box. It also refers to hardware/software that allows otherwise incompatible systems to pass data back and forth, as well as to ways of accessing information on the   Internet.

Lip of the Blade:

Wiping edge.

Lithographic Inks:

The vehicles of these inks are usually longer and more viscous than those for letterpress inks. The main difference between letterpress and offset inks is that offset inks are two to four times stronger; they contain that much more pigment. This strength of pigment is required because the offset process lays down a thinner ink film than other processes.

Lithography:

A method of printing from a plane surface (as a smooth stone or metal plate) on which the image to be printed is ink-receptive and the non- printing area is ink repellent.

Live Area:

Area on a mechanical within which images will print. Also called safe area.

Livering:

An irreversible increase in the body of inks as a result of gelatin or chemical change during storage.

Log:

A master roll of paper from which finished rolls are slit, spliced and rewound for shipment to the printer.

Logo (Logotype):

A company, partnership or corporate creation (design) that denotes a unique entity. A possible combination of letters and art work to create a "sole" entity symbol of that specific unit.

Long Ink:

An ink that has good flow in the fountain.

Low Resolution:

Low-quality reproduction because of a small number of dots or lines per inch (sometimes called lo-res).

Look-up Table:

A set of values in tabular form for input or output relationships. Such tables are most often associated with color calibration issues and determining how a color system translates from one color space to another.

Loupe:

(Pronounced "loop") From the German word for magnifying glass, a lens used by photographers, printers and designers to examine details of a printed image.

Low Key:

Describes an image that mainly consists of mid-tones and shadows.

LPI (Lines per inch):

Measure of resolution for halftones.

Lugs:

A shaft or mandrel components that, when expanded through the use if high pressure air, secures the substrate core to the shaft or mandrel

Lumen, lm:

The unit of luminous flux. The lumen is the luminous flux emitted within 1 steradian by a point source having a luminous intensity of 1 candela.

Luminosity function (y) (CIE):

A plot of the relative magnitude of the visual response as a function of wavelength from about 380 to 780nm, adopted by CIE in 1924.