Graphic Communications
Terms and Definitions
Printing Unit
A set of printing cylinders, e.g. plate cylinder, rubber
blanket cylinder and impression cylinder in an offset
printing press.
Image Carrier
The material which is printed from, e.g. offset plate,
screen frame or gravure cylinder.
Offset Lithography
It uses thin aluminum metal or polyester plates with
the image and non-image areas on the same plane.
It is based on the face that oil (ink) and water do not
mix. It uses the offset principle in which ink is offset
from the plate to a rubber blanket on an
intermediate cylinder, and from the blanket to the
paper on an impression cylinder.
Letterpress
Letterpress is the method of printing Gutenberg
invented in 1440 and has been used for job and
commercial printing. It is a relief method of printing
that can print from cast metal type, molded duplicate
plates, or photopolymer plates on which the image
or printing areas are raised above the non-printing
areas.
Flexography
Flexography is a form of rotary web relief printing
like letterpress but using flexible rubber or resilient
photopolymer relief plates, and fast-drying lowviscosity, solvent-based, water-based, or UV-based
inks fed from an anilox inking system.
Gravure
Gravure image areas consist of cells or wells etched
or engraved into a copper cylinder, and the unetched surface of the cylinder represents the nonprinting areas. The image cylinder rotates in a bath
of ink. The excess is wiped off the surface by a
flexible steel doctor blade.
Screen Printing
This method employs a porous screen of fine silk,
nylon, or stainless steel mounted on a frame. A
stencil is produced, manually, photomechanically, or
electronically in which the non-printing areas are
protected by the stencil. Printing is on a wide range
of substrates under the screen by applying ink with
a thick consistency forced through the fine mesh
opening with a rubber squeegee.
Digital Printing
Printing by plateless imaging systems that are
imaged by digital data from prepress systems.
Includes toner, ink-jet, and other processes.
Printing Plate
Image carrier used in offset printing.
Substrate
Any material that can be printed on, such as paper,
plastic, and fabric.
Basic Size
In inches, 25x38 for book papers, 20x26 for cover
papers, 22.528.5 or 22.535 for bristols, 25.5*30.5 for
index.
Basis Weight
The weight in pounds of a ream (500 sheets) of
paper cut to a given standard size for that particular
grade; e.g., 500 sheets 25*35" of 50-lb book paper
weight 50 pounds.
Caliper
The thickness of paper, in thousandths of an inch.
Coated Paper
Paper having a surface coating that produces a
smooth finish.
C1S
Paper which is coated on only one side.
C2S
Paper which is coated on two sides.
Ream
500 Sheets of paper.
Bond Paper
A grade of writing or printing paper where strength,
durability, and permanence are essential
requirements; used for letterheads, business forms,
copying, and general printing requirements, etc. The
basic size is 17 x 22".
Book Paper
A general term for coated and uncoated papers. The
basic size is 25" x 38".
Grain Direction
The direction in which most fibers lie that
corresponds with the direction in which the paper is
made on a paper machine.
With the grain
Folding or feeding paper into a press with the grain
of paper parallel to the blade of the folder or the axis
of the impression cylinder.
Against the grain
Folding or feeding paper at the right angles to the
grain direction of the paper. Also called crossgrain.
Pigments
In printing inks, the fine solid particles used to give
inks color, transparency, or opacity.
Vehicle
The fluid component that is used as a carrier for the
pigment.
Modifiers
Modifiers are added to the ink in particular to
influence drying, flow behavior, and abrasion
resistance.
SkillsUSA District 3 Conference
Wednesday, February, 24th 2016
At Keefe Tech.
SkillsUSA State Leadership and Skills
Conference
Thursday – Saturday April 28th to 30th
Marlboro Best Western Hotel and Conference Center