Pp
P
unit symbol in the metric system for peta.
p
unit symbol in the metric system for pico; abbreviation for pica.
Pa
unit symbol in the metric system for pascal.
packaging
the process of physically locating, connecting and protecting circuits, devices
or components.
pack-up
a built-up surface beneath the screen, used to ensure good contact between
the stencil and the screen during adhesion.
pad
an object made of silicone rubber that is used to transfer ink from an engraved
plate to the substrate.
padding
the layers of felt, waterproof plastic, and black gray cloth applied to the
surface of the printing table onto which adhesive can be coated to hold the
textile substrate in position for screen printing.
pad transfer printing
method of transferring images from a photoengraved plate, made of steel or
plastic, to a round, irregular, or flat surface with a silicone rubber pad.
page layout
the process and software that prepares artwork, text and other elements to be collected and prepared for printing within a specific area.
pagination
the assembly of printed matter into a page format.
paint mill
refer to ball mill.
palette
a finite set of distinct colors that can be displayed by a video, printing,
or computer system.
palette knife
a small, flexible blade with handle used for mixing small batches of ink or
color on a slab; spatula.
pallet
a low, sturdy portable platform on which materials may be placed for handling
in quantity.
PAN
acroynm for polyacrylonitrile.
panchromatic
an emulsion or film that is sensitive to the light of all visible colors.
panel
(1) a section of the crown of a cap. (2)
division of a job based on a device's production area. Also called a tile.
panel program
a service where the manufacturer provides apparel parts to be decorated and
returned for assembly.
pantograph
a device used to reduce or enlarge images proportionately.
Pantone® system
a patented printing ink color matching system involving a range of stock colors
with which, by intermixing in prescribed combination and amounts, an ink
mixer can obtain a wide range of tints, tones, shadings, and intermediate
hues. (Trademark of Pantone Inc.).
paper
a sheet of fibers (wood) manufactured on a fine wire from a water suspension.
paperboard
one of the two broad subdivisions of paper that is generally 12 points (0.3
mm/0.012 inch) or more in thickness.
paper conditioning
to bring paper temperature and moisture content into equilibrium with the atmospheric
conditions of the pressroom.
paper equilibrium tester
an instrument used to indicate maximum changes likely in size or shape of stacked,
wrapped paper, once the wrapping has been removed.
paper stencil
a screen printing stencil made of thin paper that is adhered to the mesh.
paper size, International
common paper sizes in Europe and Japan — A3 297 x 420 mm (11.7 x 16.5
in), A4 210 x 297 mm (8.3 x 11.7 in), A5 148 x 210 (5.8 x 8.3 in), B4 250 x
353 mm (10.1 x 14.3 in), B5 176 x 250 (7.2 x 10.1 in), B6 125 x 176 mm (5.0
x 7.2 in).
paper thermometer
a strip of heat sensitive paper that indicates achieved temperature; also refer
to temperature tapes.
parallax
the difference between the field-of-view seen through the viewfinder and that
recorded on the film.
parallelogram easel
an easel used in the construction of three-dimensional displays that requires
assembly with parallel sides.
parallel-receding press
a screen printing press where the top frame assembly rises up and back or in
some models, up and sideways simultaneously, while remaining parallel or
horizontal.
parameter
controllable variables that describe the conditions of a process.
para red
an organic red pigment used in ink manufacturing.
parchment
(1) historically, a sheet made from the skins of goats; (2) an artificial paper
made to resemble original; refer to vegetable parchment or vellum.
Pareto chart
a combination histrogram/cumulative line chart that helps identify causes that
have the greatest impact on a problem.
parian ware
a soft porcelain composed of one part china clay and two parts feldspar, used
for making statuettes.
parison
a hollow moltent plastic tube from which an object is blow molded.
parity
a set of binary digits where the total numbers of digits in each expression
is deliberately kept odd or even by the addition of an extra digit whenever
necessary.
particle
solid or liquid matter generally between 0.001 mircron and 1000 mircrons in
size.
particulate
smallest unit; a substance that consists of a minute particle of solid or liquid
matter, usually suspended in air.
parting agent
refer to release agent.
particles per million (ppm)
volume of vapor or gasses in the air.
parylene
a linear, highly crystalline polymer that is deposited from the vapor phase
by a process similar to vacuum metalization, used as a conformal coating
for silicone rubber keypads and electronic assemblies.
pascal (Pa)
a basic unit of pressure equal to the pressure resulting from a force of one
Newton acting uniformly over an area of one square meter (N/m2).
passive component
a component that cannot control voltage or current to produce gain or switching
activity.
passive substrate
an insulating substrate such as glass or ceramic material that provides physical
support.
paste
a smooth textured semi-solid substance.
paste gold
gold particles in a suspension of heavy paste that can be thinned to desired
consistency, used in glass decorating.
pastel
a soft light hue or tint.
paste up
a mechanical, composition of flat objects pasted on a backing.
pasting
to cause to adhere by applying paste.
patent
(1) a grant made by a government to an inventor giving sole rights to produce,
use, and sell the invention for a certain period of time; (2) something protected
by such a grant.
patent coated board
newsboard that has been coated to improve the surface.
pattern coated
refers to width and spacing arrangement of strips or designs of adhesive printed
lengthwise, crosswise, or in predetermined designs on decal pressure sensitive
stock during its manufacture.
pattern plating
the electroplating of specified areas, as in a printed circuit, by screen printing
a plating resist over those areas not to be plated.
pattern
a plan, diagram, or model to be followed in producing an item.
PC
acroynm for polycarbonate.
PCB
acroynm for printed circuit board.
PCE
acroynm for pyrometric cone equivalent.
PDF (Portable Document Format)
An electronic document format from Adobe that allows the distribution of digital files across any platform that can display a document as originally designed and formatted without having the software application or fonts on the viewing computer.
PE
acroynm for polyethylene.
peacock blue
a fugitive, clean, green-shade blue pigment widely used in screen printing
inks.
peak firing temperature
the maximum temperature at which firing of cermet or glass inks can be accomplished
without deterioration or destruction of the imprint.
pearlescence
a "pearl-like" appearance produced by adding powdered titanium dioxide
and mica as colorants to screen printing ink.
pebble mill
refer to ball mill.
pebble stitch
a garment with an irregular or rough surface texture.
pebbling
a finishing process that gives paper a grainy, ripple surface.
peel adhesion
the force required to remove a strip of overlay (usually 25.40 mm or one inch)
from a material at a fixed rate (usually 304.8 mm or 12 inches/minute) at
an angle of 90º from the surface.
peel, automatic
a device on larger automatic screen printing press that lifts the screen behind
the moving squeegee.
peeling
a defect caused by detachment of a printed film from the substrate, or detachment
of all or portions of a stencil film from the mesh of a printing screen.
PEL
acroynm for permissible exposure limit.
Pellon®
trademarked product, refer to proofing squares.
pendulum motor
a display motor that has an oscillating or swinging motion.
penetrate
a wetting agent that increases ink penetration into a substrate.
penetration
the surface absorption of an applied ink or coating by a substrate with a porous
surface.
pennant
a piece of plastic or cloth that is pointed at the bottom and is usually hung
from its top.
percent dot area
the black area on film exposed and processed, expressed on a scale of 0-100. (A
90 percent dot area in a halftone positive would be equivalent to a 10 percent
dot area in the corresponding negative.)
percent grayness
densitometric relative measure of achromatic density in a color as compared
to the major filter density.
percent open area
the relationship between that part of a screen mesh that is blocked by threads,
and that part that is open, or between threads; refer to aperture percentage.
percutaneous
the ability of a chemical to be absorbed through the skin.
perfect cut
an overlay that is prepared by cutting the film portion exactly against the
edge of the trapping color.
perfecting press
an offset press that prints both sides of a sheet of paper simultaneously.
perfector
a printing press that prints both sides of the sheet with one pass through
the machine.
perforated nickel screen
an electroformed rotary screen with good stability and flexibility characteristics.
perforating wheel
a manual or computer drive toothed round object that rotates freely to trace
patterns that are brushed with dust or powder to transfer an outline, also
called pounce pattern.
performance
the quality of a substance or bond to resist deterioration.
performance specification
a specification that states the desired operation or function of a product
but does not specify the materials from which the product must be constructed.
perilla oil
a vegetable-origin drying oil with properties between tung and linseed oil.
peripheral
any of a number of hardware devices that extend or enhance the performance of the computer and are not part of the CPU, though some are mounted inside the case of the computer.
permanence
the quality of a substance or bond to resist deterioration.
permenant adhesive
a pressure sensitive adhesive that once applied becomes extremely difficult
to remove without leaving a residue on the surface where the decal has been
applied.
permanent ink
ink that resists fading or change of color when exposed to light and air.
permanent paper
a paper that resists the effects of aging, usually acid-free, used for archival
or artistic (serigraph) prints.
permanent violet
a light resistant, tungstated or molybdated methyl violet pigment used in screen
printing inks; carbazole violet.
per mill
per thousand.
permissible exposure limit (PEL)
concentration in air that has been declared safe to breathe by the US Occupational
Safety and Health Administration (OSHA).
permittivity
the ratio of electric flux density produced by an electric field in a medium
to that produced in a vacuum by the same field; also refer to dielectric
constant.
persian orange
a clean, brilliant, transparent flaked orange ink pigment.
PET
acroynm for polyeylene terephthalate.
peta
a prefix utilized in the metric system of measurement that denotes 10 to the
fifteenth power (1015) or 1 000 000 000 000 000.0. Its symbol
is P.
PETG
acroynm for polyeylene terephthalate cyclohexanedimethanol.
petroleum naphtha
weakest hydrocarbon solvent with KB value of 20.
PF
acroynm for phenolic.
PFP fabric
"prepared to print" fabric that has been pre-scoured and heat-set to
make it suitable for printing.
pH (pH value)
a measure of the acidity or alkalinity of a solution on a scale of 1 to 14. (A
substance with a pH value of 7 is neutral; acids have pH values below 7; alkalis
have pH values above 7.).
phase
a time-based relationship between a periodic function and a reference. (In
electricity, it is expressed in angular degrees to describe the voltage or
current relationship of two alternating waveforms.)
phase change printer
an ink jet printer where a solid ink is heated and liquefied for disbursement.
phenolic (PF)
an opaque thermoset plastic produced by the condensation of an aromatic alcohol
with an aldehyde, particulatly of phenol with formaldehyde, resistant to
solvent and water, non-recyclable, permenant shape, cannot be reformed.
phloxine (magenta)
a fugitive organic dyestuff used to produce brilliant red color; a bluish red
pigment used in process color screen printing inks; also refer to eosin.
phosphate glass
a type of glass where the glass former is phosphorous pentoxide instead of
silicone.
phosphor
material that emits light when irradiated by cathode ray or when placed in
an electrical field.
phosphorescence
(1) a property of a certain class of films or coatings which utilizes the effect
of light on chemical elements (phosphors) within the structure of the product
to provide a visible color in the absence of a normal light source; (2) the
luminous appearance of objects having this property.
photocell
a device that converts the energy in a light ray into electrical energy; also
referred to as photoelectric cell.
photochemical oxidant
air pollutant formed by the action of sunlight on oxides of nitrogen and hydrocarbons
that contribute to the formation of smog.
photochemistry
the study of chemical actions influenced by the action of light.
photochromatic ink
ink that changes color or looses color when exposed to a UV light source and
returns to its original color when removed from the presence of UV light.
photoconductive
a material that carries electricity in the light and serves as an electrical
insulator in the dark.
photoconductor
an insulator that conducts electricity in the light and serves as an electrical
insulator in the dark.
photodegradation
the chemical breakdown of a substance caused by exposure to light.
photoengraving
a process of reproducing graphic material by photochemical transference of
the image onto a sensitized plate and developing in etched relief.
photofabrication
refer to chemical milling, as required for pad printing.
photoflood light
electric incandescent filament lamp that provides a high intensity light source
on relatively low current consumption.
photographic filter
designed to permit passage of specific colors through the lens to the film;
manufactured of glass or gelatin in a various colors for use in front of
the camera lens to produce pre-determined effects of colors on the film.
photographic sponge
a very fine textured, soft synthetic foam composition suitable for removing
excess water from freshly processed camera film without scratching the emulsion.
photography
the process or technique of rendering optical images on photosensitive materials.
photogravure
a printing process where the image is etched into a plate cylinder; also referred
to as gravure.
photoinitiator
a substance that absorbs light and becomes energized into forming free radicals
and promotes polymerization of reactive monomers and oligomers.
photo mask
(1) a manually produced opaque design on masking film for preventing exposure
of predetermined areas of photographic film or stencil material; (2) a photographically
produced duplicate of a halftone negative or positive with very thin density,
designed to add slight density to the halftone film from which it was made
to reduce future exposure effects in controlling color density in the final
printing.
photo multipler tube (PMT)
a single image reciever in a drum scanner; yields better shadow detail.
photomechanical transfer (PMT)
(1) a diffusion process whereby positive, reversal, or negative print can be
made without an intermediate negative process step, also refer to diffusion
transfer; (2) a trademark of the Eastman Kodak Company.
photometer
instrument used for measuring luminous intensity, luminous flux, illumination
or intensity.
photomicrography
the process of photographing minute objects magnified through a microscope.
photo opaque
refer to opaque.
photopolymer
a plastic that changes upon exposure to light.
photopolymer emulsion
a presensitized emulsion where a photoreactive salt is attached to the polyvinyl
resin during manufacturing, requires no additional sensitizer; also known
as SBQ-photopolymer emulsion.
photoreactive resin
a natural or man-made resin or polymer that chemically reacts with itself or
with other polymers under the influence of light.
photoscreen
a combination term used to indicate photographic screen printing stencils or
the film or direct emulsions from which the stencils are made.
photoscreen stencil
any screen printing stencil made by photomechanical processes.
photosensitive resist
printable solution that is not affected by etching chemical but which is designed
to be affected by exposure to actinic light applied through a mask to a predetermined
pattern and later to the chromium tanning process to stabilize the protected
portions of the resist film.
photosensitizer
a chemical agent that is affected or changed by light or other radiant energy;
a substance that absorbs light and passes its energy to another substance
which then reacts.
photostencil
any light sensitive system that utilizes original or photo-generated artwork
to produce a stencil.
photoresist
a light sensitive coating that is applied to a metal surface.
phototype
type set by photographic means.
phototypesetting
act of preparing type material by photographic means to provide a positive
film with the type matter in predetermined arrangement to form a line or
lines.
Photo YCC
a color standard established by Eastman Kodak that is used to define color
space.
phthalocyanine blue (cyan)
blue green organic pigment used in process color printing ink, characterized
by excellent light fastness and resistance to solvent, acid, and alkali,
resistant to bleed, good transparency.
phthalocyanine green
green organic pigment with excellent lightfastness and resistant to acid and
alkali, bleed resistant, good transparency.
PI
acroynm for polymide.
pi
(1) a mathematicl symbol representing the ratio of the circumference of a circle
to the diameter, the numerical value of which is 3.14159265+ or 3.14; (2)
foundry type mixed and jubbled in an unusable condition.
PIA
acroynm for Printing Industries of America.
pica
printer’s unit of linear measurement used for measuring type lines and
artwork; equal to 12 points or 1/6 of an inch.
pick
paper fiber or coating lifting from the surface of a sheet during the printing
process.
pickup
the adhesion of ink from the first color printed to the underside of the screen
for the second or succeeding color.
pico
a prefix utilized in the metric system of measurement that denotes 10 to the
negative twelfth power (10-12) or 0.000 000 000 001; symbol is
p.
pictograph a pictorial respesentation used with or instead of text.
PID
abbreviation for proportional, integral, derivative; a three-mode control where
the controller has time proportioning (auto reset) and derivative action.
piezo-electric
ink jet technology that uses a mechanical electric charge instead of heat to
drive microdroplets through a nozzle.
piezoresistance
resistance that changes with stress.
pigment
(1) a substance used as a colorant; a finely divided solid, organic or inorganic
coloring material insoluble in the medium into which it is added; (2) the
color substance in an ink that absorbs and reflects light.
pigment dye
textile dye formulated from appropriate vehicles and pigments of mineral or
synthetic origin.
pigment emulsion
emulsion type screen printing ink that contains pigments for coloring effects
mixed with emulsified vehicle.
pigment paper
refer to carbon tissue.
pigment volume
the percentage by volume of a pigment in the nonvolatile portion of an ink,
calculated from bulking value and other data.
pile feeder
an automatic sheet feeding mechanism.
piling
the tendency of a textile fabric to mat into ball-like "pills" that
cling to the surface of the fabric.
pill
a tangled ball of fibers that appears on the surface of a fabric.
pimple
any small defect such as a protrusion on the surface of a plastic.
pincushion distortion
an image that compressed toward the center with distortion most noticeable
at the center of horizonal or vertical edges.
pin feed
refer to feed slots.
pinhole
(1) imperfection in the form of tiny transparent dots that appear in printing
screens or in process films after development; (2) print imperfection caused
by a combination of surface tension of ink and low receptivity of the substrate,
resulting in very small separations of the ink after printing and before
drying; (3) small hole in a decoration extending through the color to the
substrate.
pinpoint light source
refer to point light source.
pin registration
a system of registering two or more sheets very accurately by means of punched
holes placed over prespaced pins located outside the design area, results
in very accurate alignment of the sheets.
pin scratch
a pattern or design formed by scratching lines through the raw glaze or decoration
with a sharp point.
pinout
a schematic that describes the circuit output requirements for an electronic
device.
pique
a knit fabric with a waffle-like appearance.
pit
a small depression or defect on the print surface, similar to a dimple.
pitch (fine pitch)
a solid or semi-solid asphaltic substance used in some inks to add flow or
length.
pixel
(1) the smallest tonal element in a digital imaging or display system; (2)
a tiny picture element that contains red, green, and blue information for
color rendering on a monitor or scanner.
pixel depth
the number of bits of tonal range capability assigned to the pixels in an image.
(Momochrome 1 bit deep; grayscale 8 bits deep; RGB 24 bits deep; CMYK 32 bits
deep).
pixel dropping/skipping
sub sampling to reduce the number of pixels in an image by dropping every nth
pixel from the scan.
pixel replication
creating more pixels than are actually scanned by replicating every nth pixel
to create the nth +1 pixel.
pixelization
graininess in an image when the pixels are too large.
pixels per inch (ppi)
a measure of the density of scanned information in an image.
PL
acroynm for polyolefin liner.
plain weave
a pattern of weave whereby the warp and filling thread (weft) cross alternatively
over one and under one. (Plain weave mesh is the least pliable but most
stable).
planimeter
a device that uses a microscope, television camera and receiver, and a small
computer to visually and mathmatically evaluate a dot area.
planishing
method whereby heat and pressure are applied to a film, resulting in a surface
texture.
planography
a printing process where the image and non-image areas lie in the same plane
of the plate, such as offset printing.
plasma display
a display screen that has a gas contained between two panels where the x and
y axis dots are electrically charged causing them to glow.
plasma treatment
an electrically neutral highly ionized gas made of ions, electrons, and neutral
particles used to treat polyolefin plastic prior to printing.
plastic
(1) a synthetic organic polymeric material, solid in its final form, that is
either a homogenous polymer or resin combined with fillers, plasticizers,
pigments, stabilizers and/or other additives; (2) any of various complex
organic compounds produced by polymerization, capable of being molded, extruded,
or cast into various shapes and films, or drawn into filaments for fabrics.
plastic, engineering grade
plastic with properties suitable for engineered product requiring up to 125ºC
(257ºF).
plastic, high performance
a plastic suitable for product designs requiring stability above 175ºC
(347ºF).
plastic deformation
a forced change in the dimensions of an object that does not return to the
original, when the applied force is removed.
plastic fluids
fluids where flow does not occur until a critical shear stress (yield stress)
is exceeded.
plasticity
the property of a material that allows it to be repeatedly deformed without
rupture, when acted upon by a force sufficient to cause deformation, and
allows it to retain its shape after the applied force has been removed.
plasticize
to soften a material and make it plastic or moldable either by means of a plasticizer
or the application of heat.
plasticizer
chemical agent added to a plastic composition to make it pliable, softer, and
more flexible.
plastic viscosity
refer to viscosity.
plastisol
a dispersion of finely divided resin in a plasticizer or series of plasticizers,
usually 100% solids with no volatiles. (If the mixture contains volitiles
is is known as an organosol).
plastisol fusion rate
the curing time required by a plastisol deposit with the application of a specific
temperature elevation.
plastometer
an instrument for determining the flow characteristics of a thermoplastic,
under specified conditions.
plate
(1) in screen printing, indicates the printing screen; (2) in other printing
methods, the material on which the desired copy or design has been etched,
molded, or transferred.
platesetter
a device that uses laser light or themal imaging to expose a printing plate
at high dpi resolution (1200 dpi or higher).
plated-through holes
a plating technique in electronic circuitry where the holes drilled in the
substrate for attaching wire lead components are plated with metal for the
entire depth of the holes as they extend through the thickness of the substrate.
plate glass
obsolete term refer to float glass.
plate maker (plate printer)
an illuminated vacuum table for exposing photosensitive material.
platen
(1) the flat plate of a printing unit of a printing press that serves to hold
the substrate in position during printing or finishing; (2) a fixture on
a T-shirt printing machine or device that supports the item to be printed;
(3) base or heating element of a heat transfer press.
platen dryer
a single panel flash cure unit generally used for wet-on wet garment printing.
platform
refers to the particular proprietary computer hardware design. This can be Intel, Windows, Macintosh, etc.
platform easel
an easel that provides a platform on which merchandise can be displayed.
platform lock
a lock that attaches a display platform to its base.
plating resist
a screen printing compound, when applied to conducting elements in a printed
circuit, prevents subsequent plating of those portions with metal.
Plexiglas®
a light, transparent, weather resistant thermoplastic; a trade name for acrylic
plastic sheet, which through long usage, is incorrectly regarded by many
as a generic term.
pliability
refer to flexibility.
plotter
(1) a mechanical drawing device that produces images by pen or electrostatic
process; (2) an output device for recording an image in raster fashion on
a photographic emulsion or print image carrier; (3) a device that interprets
information sent from a computer and moves a tool head to a series of coordinates
based on the devices x and y axis coordinates.
plugging shadows
destruction of, or loss of, detail in the shadow areas of a halftone film or
print.
ply
a designation of thickness for cardboard and other blanks indicated by the
number of plies or layers used in the laminate. (Plies are converted into
points with a point equal to 1/1,000 inch).
PMA
abbreviation for a pigment that has been precipitated with phosphomolybdic
acid to give it permanence and insolubility.
PMMA
acroynm for polymethyl methacrylate; acrylic plastic.
PMS
acronym for Pantone Matching System, a registered trademark of Pantone, Inc.;
a color matching system for choosing and matching specific spot and process
colors.
PMT.
(1) acronym for photomechanical transfer, a trademark of the Eastman Kodak
Company; (2) acronym for photo multiplier tube.
pneumatic screen printing machine
a screen printing machine, semi-automatic or automatic that is powered by compressed
air rather than by an electric motor or other mechanical power source.
pneumatic tensioning system
a compressed air-actuated stretching device used for tensioning mesh before
it is attached to the frame.
PO
acroynm for polyolefin.
POC
acroynm for point of contact.
pocket connector
a pocket for connecting two display parts to each other.
pocket hinged-back
a pocket made out of a display back.
pocking
dimpling on the surface of a print.
point
(1) a standard unit of measure in printing where 72 points equal one inch;
one point equals 1/1000 inch; (2) a measure of cardboard thickness (50 point
board is specified .050 and is 5/100 inch or 50/1,000 inch thick).
point light source
a light source that has a single point or filament.
point of purchase/point of sale
the location at which a product is sold such as the store or retail counter.
point source
any discernible, confined and discrete conveyance, including, but not limited
to any pipe, ditch, channel, tunnel, conduit, well, discrete fissure, container,
rolling stock or vessel, from which pollutants are or may be discharged.
poise
a unit for measuring viscosity, equal to one dyne per second per square centimeter;
one gm/cm/sec.
Poisson’s ratio
absolute value of the ratio of transverse strain to axial strain resulting
from a uniformly applied axial stress below the proportional limit of the
material.
polar adhesion
adhesion to a surface that has polarity such as wood, paper and cloth.
polar solvent
a solvent with oxygen in their molecules such as water, alcohol, ketone, esters,
or other solvent having a high dielectric content.
polishing
the name of a defect that occurs in matte ink, when the gloss of a print can
be increased by rubbing.
pollution
undesirable foreign materials, usually waste, in the air, water or on the land.
polyacrylonitrile (PAN)
a synthetic fiber used as a base material or precursor in the manufacture of
certain carbon fibers.
polyamide
alternate spelling for polyimide.
polybasic acid
maleic, succinic, and phthalic acid having two or more carboxyl groups per
molecule.
polycarbonate (PC)
a thermoplastic material derived from the reaction of aromatic dihydroxy compounds
with carbonic acid with high impact strength, low water absorption, heat
and moisture resistant, and good electrical and optical properties.
polychloroprene
chemical name for neoprene.
polychrome
a multi-colored image or print.
polydomes
spherically formed element in polyester circuit material to provide tactile
response in electronic switches.
polyester (UP)
a thermosetting plastic derived from unsaturated ester polymer dissolved in
a monomer such as styrene used in the production of film and fiber, strong,
extremely tough, adversely affected by UV light and chlorinated solvents,
but resistance to most other solvents, acids, and salts.
polyester dome
refer to polydome.
polyethylene (PE)
a thermoplastic produced by the direct polymerization of ethylene at high temperatures
and pressures; process variations and the lowering of temperature and pressure
create high, medium, and low density materials.
polyethylene terephthalate (PET)
a thermoplastic formed by reaction of either purified terephthalic acid or
dimethyl terephthalate with ethylene glycol, used for synthetic fiber and
film, blow molded, and thermoformed parts.
polyhydric alcohol
alcohols such as glycol and glycerol containing more than one C-OH group per
molecule.
polyimide (PI)
a thermoset or thermoplastic formed by the reaction of a dibasic acid with
a diamine to form a salt and then a polymeric amide; polyamide resins are
nylons.(Sometimes spelled polyamide).
polymer
a long chain molecular structure compound formed by a reaction between monomers
and or oligimers, having functional groups that permit their combination
to proceed to high molecular weights under suitable conditions by polymerization
or polycondensation. (Polymers can be plastic, elastomers, liquids, or gums).
polymerization
a chemical reaction initiated by a catalyst, heat, light, or water causing
monomers and/or oligimers to linked together to form a polymer.
polyolefin (PO)
a thermoplastic (polyethylene or polypropylene) that is based on polymers of
olefin.
polypropylene (PP)
a thermoplastic material similar to polyethylene with a higer molecular weight
resulting from polymerization of propylene gas; the lightest of the thermoplastics.
polystyrene (PS)
a thermoplastic material derived from the polymerization of styrene that is
clear and exhibits high stiffness, good dimensional stability, low specific
gravity and excellent electrical properties.
polyvinyl acetate (PVAc)
a vinyl polymer or copolymer mainly used in the manufacturing of adhesives
and emulsions.
polyvinyl alcohol (PVOH)
a thermoplastic that is produced from full or partial hydrolysis of vinyl ester
such as vinyl acetate resulting in the replacement of some or all of the
acetyl groups with hydroxyl groups.
polyvinyl alcohol emulsion
a solution made by dissolving specific amounts of a fine white synthetic powder
known as polyvinyl alcohol and ammonium or potassium bichromate in specific
volumes of water.
polyvinyl chloride (PVC)
also known as vinyl, a thermoplastic resin used in both solution and dispersion
coating systems and is polymerized from vinyl chloride monomer by free radical
techniques, exceedingly versatile, used for products from thin films to complex
molded parts.
polyvinyl fluoride (PVF)
a polymer of vinyl fluoride (fluoroethylene), a monomer structurally similar
to ethylene with a high melting point, chemical inertness and resistance
to ultraviolet light.
POM
acroynm for polyoxymethylene; acetal plastic.
POP/POS
acroynm for point of purchase or point of sale.
poplin
plain weave class of fabrics having fine cross ribs.
porcelain
a glazed or unglazed vitreous ceramic whiteware.
porcelain process
a method of producing glazed ware where a ceramic body and/or glaze are matured
together in the same firing.
porcelain sign
a traditional type of metal sign utilizing porcelain enamal paints topped by
a ceramic slip that is fired to create a durable glass like coating that
is impervious to the environment.
porosity
the structure and density of a sheet; the ratio of the volume of the pores
to the volume of the mass of a substrate.
porosity percentage
the percentage of the total volume of a material occupied by both open and
closed pores.
porous surfaces (porosity of substrate)
surface of substrate with open pore construction as in paper that have the
capability of slight absorption, thus offering a mechanical bond with ink
applications.
portrait
a page format that has greater height than width; page layout in vertical format.
positionability
the condition of a pressure sensitive product imposed during manufacture that
permits repositioning after application.
positive
film or vellum print where the light and dark areas appear as they do naturally,
corresponding to the original copy.
positive temperature coefficient
an increase in resistance due to an increase in temperature.
post cure
(1) the continuation of a polymerization (curing) process within a UV ink or
coating after exposure to UV radiation has been terminated; (2) a final or
more complete resolving of organic materials after the initial curing process;
(3) additional elevated temperature cure, usually without pressure to improve
final properties and complete the cure.
post hardening
re-exposing a screen after it has been developed to fully harden the emulsion.
PostScript® point
a slight revision to the point measurement system equal to 1/72 of an inch. (Most
graphic software utilizes this defined value for a point).
poster
(1) a message presented to public view to promote a product, event, civic action,
etc., usually depending more on illustration for attraction than copy; (2)
a very large sales promotion message screen printed in conveniently handled
sections, for pasting up on outdoor poster boards.
poster board
a specific weight of cardboard beginning with caliper 0.024 (24 point). (Standard
sheeted sizes are 559 x 711 mm (22 x 28 inches) and 711 x 1118 mm (28 x 44
inches)).
posterization
(1) a special effect performed on a piece of art that compresses all of the
tonal values into a smaller range of tones usually not more than four; (2)
a special effect created by using a limited number of gray levels within
an image, computer created by setting a defined number of gradiant steps
in a bitmapped image.
poster paper
a name commonly used by printers for paper sheet material used in the printing
of an outdoor advertising poster, usually wet-strengthened with opaque additives
for minimum see-through when posted, rough on one side to facilitate pasting.
poster plates
a paper tissue stencil that is hand-cut and attached to the screen.
poster style art
refer to block color.
PostScript®
a page description programming language created by Adobe. A device-independent industry standard for outputting documents and graphics.
PostScript point
a slight revision to the "Point" measurement unit. A Postscript point is exactly 1/72 of an inch. Most graphics software utilizes this refined value for a point.
post sensitizing
a technique of coating stretched mesh with unsensitized emulsion and permitting
the coat(s) to dry, then wiping the sensitizing solution onto both surfaces
with a cotton pad under safe light conditions with a sensitizer just prior
to use.
potassium bichromate
orange red crystals sometimes used in the preparation of solutions for sensitizing
carbon tissue, screen printing films, and coatings for screen printing stencils. (Bichromates
are considered an environmental and health hazard and are no longer used
in the industry).
pot life
(1) the length of time that a chemical composition can be stored before it
begins to deteriorate or is no longer useful; (2) time during which a liquid
resin remains workable as a liquid after catalyst, curing agent, and/or promoter
is addded.
pound
a unit of weight equal to 16 ounces avoirdupois or 453.592 grams.
pound per square foot (psf)
a unit of pressure equal to the pressure resulting from a force of one pound
applied uniformly over an area of one square foot.
pounds per square inch (psi)
a measurement of pressure exerted per unit area.
power factor
cosine of the angle between the voltage applied and the current resulting.
powdered adhesive
a thermoplastic bonding agent primarily used to aid a plastisol transfer to
adhere more efficiently to nylon or polyester substates.
PP
acroynm for polypropylene.
PPD
refers to PostScript Page Description, a small file used to describe a particular printer’s characteristics and capabilities to a graphics or word-processing software.
PPE
acroynm for personal protective equipment.
ppi
acroynm for pixels per inch.
ppm
acroynm for particles per million.
pre-bowing
the application of force to the sides of a static frame prior to gluing tensioned
mesh to the frame.
prebreaking
the breaking of scores before shipping a display.
precision
state of being precise as to meaning, exactness, accuracy.
precision printing
refer to close tolerance printing.
pre-flight
a process of checking a job for possible problems before the job is sent for
final output.
preheat cycle
to heat before hand using a time and temperature relationship.
preheat zone
that portion of a lehr where all organic compounds are burned off before entering
the firing zone.
premasking
the application of protective paper or tape to the surface of a substrate prior
to printing.
prep
the process of preparing screen mesh to receive a photographic stencil; a make
ready procedure prior to use.
pre-pack
a display designed to be packed with merchandise by the advertiser and shipped
as a unit.
prepreg
a thermosetting plastic, such as polymide, reinforced with glass cloth for
use as a circuit board laminate, especially for multilayer boards.
pre-press
all preparatory operations performed before the actual printing operation.
preprinting
screen printing a distortion pattern or design onto a plastic sheet that will
be heat or vacuum formed, where during forming, the distortion is transformed
into a correct image; refer to distortion copy.
pre-scouring
washing of fabric to remove residual spinning oils and waxes that could interfere
with dye acceptance.
prescreened film
a sensitized film for making halftone positives and halftone negatives, where
the halftone effect or dot formation is incorporated in the sensitized emulsion
of film and produces a dot pattern automatically when film is exposed to
object or copy.
presensitized film
screen printing stencil film made for making photographic stencils that has
been sensitized before shipping.
prespacing
the application of a series of die cut or kiss cut patterns in a predetermined
relationship onto an application paper in order that all marking components
or designs may be applied to the substrate at one time.
press check
an event where test sheets are examined and approved before production run
is authorized.
press proof
refer to proof.
press run
the total number of copies printed, refer to as an "edition" in fine
art serigraph printing.
pressure contact frame
a frame for holding two or more sheets face-to- face, or face-to-back, in-contact
while exposing.
pressure equalizer
a device that uses pneumatic pressure to equalize squeegee pressure along the
blade.
pressure forming
a thermoforming process where pressure is used to press the sheet to be formed
against the mold.
pressure head
that portion of a heat-release decorating machine that applies pressure to
a heat-release decal, forcing it into contact with the ware.
pressure sensitive adhesive
(1) a tacky adhesive that is applied to a sheet material to enable the sheet
to adhere to an unrelated surface by contact and light pressure without the
use of water or solvent; (2) a material that has pressure sensitive adhesive
applied either at the factory or in the screen printing plant; (3) a combination
of a face material, pressure sensitive adhesive, and liner paper.
pressure sensitive pen
a tool that allows information to be entered in a computer with a stylus in
a manner similar to writing or drawing.
pressure washer
a screen cleaning unit consisting of a device for multiplying tap water pressure
through a hose and a spray-type nozzle under high pressure.
pressurized screen printing
a printing method or device that forces ink through a stencil image of a screen
by vacuum.
pretreatment
preparing the screen mesh by degreasing and abrading before stencil application;
also refer to prep.
pretreatment standards
(1) municipal limits requiring industry to treat effluents prior to their arrival
at waste treatment plants; (2) in wastewater treatment, any process used
to reduce pollutants before the process waste-water in introduced into a
main sewer system or delivered to a treatment plant.
Preucil Ink Evaluation System
a color evaluation system where a reflection densitometer is used to measure
a printed ink film through a Wratten #25, #58, #47 filter relative to substrate,
then converts information to hue error and grayness parameters for plotting
on color diagram.
prewetting
(1) a procedure used by outdoor advertising installers of soaking printed paper
overnight prior to posting; (2) a procedure that is used to soak stacks of
water slide decals in a tray prior to application.
primary colors
in printing inks, yellow, magenta, and cyan; for light, the primary spectral
colors are red, green, and blue.
primary standard
a standard of reference units and physical constants maintained by the National
Institute of Standards and Technology (NIST) upon which all measurement units
are based (US).
primer
refer to barrier coat.
principal axis
the axis of maximum and minimum normal stress.
print
the final form of the printed image; the act of printing.
print area
the area of a printing form that produces the image or the area printed on
a substrate.
print base
the support on which the substrate is placed for printing; also refer to print
table, platen.
print cloth
plain woven fabric, not napped, weighing not more than six ounces per square
yard.
print contrast
the ratio of the difference in the density of a 75% (three-quarter) tone and
a solid print to the density of the saturated solids on a press sheet.
print cylinder
the printing base on a cylinder press that is a vacuum cylinder of stainless
steel or aluminum.
print head
a part of a screen printing press that consists of the screen carriage, the
squeegee/flood bar assembly, and the mechanical controls and fixtures.
print quality
the properties of a print that meet or exceeds cutomer specifications.
print run
the total number of prints, plus overruns, produced.
print section
that portion of a web screen printing press located after the in-feed, where
one or more print stations are located.
print shoulder
the vertical borderline between the printing, or open sections and the nonprinting
or closed sections of the stencil.
print side
the side of a screen where the ink is and the squeegee is dragged across; also
referred to as well side.
print stock
substrates to be printed.
print stroke
the movement of the squeegee across the printing screen forcing ink through
the stencil, forming the imprint.
print table
see print base, platen.
printability
(1) capable of being printed; (2) describtion of the properties of all components
in a printing process.
printed and fired circuit
refer to thick film circuit.
printed circuit
an electronic circuit produced by printing an electrically conductive pattern,
wiring, or components on a supporting dielectric substrate that can be either
rigid or flexible.
printed circuit laminate
material either fabric or paper based that is covered with a thin layer of
copper foil and used in the photofabrication process to make circuit boards.
printer dot
the individual pixel in a halftone image.
printer, nonimpact
any device that reproduces an image without striking the substrate, such as
ink jet, laser, and xerographic printing.
printer’s ream
a quantity of sheet material equal to 516 sheets.
printing down (British)
the process of exposing the photostencil to a light source.
printing frame
a specially constructed frame consisting of one opaque surface and one transparent
or glass surface that can be brought together with each other by mechanical
pressure or by vacuum.
printing ink
any fluid or viscous composition used to print, impress, or transfer an image
onto a substrate.
printing lamp
an actinic light source used in illuminating or in exposing screen printing
films and other sensitized materials.
printing paste
a formulation of screen printing ink used for ceramic and glass decoration.
printing press
a mechanical device to enable the application of ink to a substrate to reproduce
a pattern or design.
printing process
any method used to reproduce written and pictorial matter in quantity.
printing screen
the assembly of frame, mesh, and stencil from which a screen print is produced.
printings
the number of colors on an outdoor poster, multiplied by the number of sheets
upon which each color is printed.
procedures
the documented practices defining the who, what, and when of an operation.
process blue
refer to cyan.
process camera
a camera designed to accurately photograph line, solid, halftone, colored copy
and other objects to be reproduced by means of a printing method; also called
gallery camera, darkroom camera.
process capability
the total range of inherent variations in a stable process.
process colors (process inks)
inks of cyan, magenta, and yellow, semi-transparent specifically formulated
for four color process screen printing. process control
a system using feedback to monitor and manage a certain procedure.
process ink
refer to process color.
process lens
a lens having a long focal length, corrected for flat copy and used in a process
camera, or made with pantograph, divider and other such device.
process printing
the printing from a series of two or more halftone screens to produce intermediate
colors and shades, usually in four color process – yellow, magenta,
cyan, and black.
process red
see magenta.
process temperature
the temperature of the process medium, as recorded by a sensor.
process wastewater
any used water which results from or has had contact with the manufacturing
process, or for which there is a reasonable possibility of contamination
from raw material, intermediate product, final product, storage transportation,
handling, processing or cleaning.
profile
a database or file of values that apply to an imager defining its color capability
for other imagers in the same process.
profilometer
an instrument used for measuring the degree of surface roughness.
progressive proofs
a set of press proofs showing the printing sequence and the result after each
additional color has been applied.
progressive shrinkage
refer to relaxation shrinkage.
projection
(1) a pattern or design enlarged or reduced by an optical system onto a second
surface at a distance from the original design; (2) the method by which the
original design is transferred to a distant surface by means of an optical
system.
promotional quality
a garment that is lighter in weight and less expensive.
proof
a preliminary print made for inspection purposes to check details of the design
using image carrier, substrate, and ink specified for the job; a prototype
of the print job.
proofing square
a non woven material used as a test print substrate in garment printing.
proofreader marks
a series of symbols and abbreviations used by a proofreader to mark errors
on copy and to indicate corrections to be made.
proportion scale
a circular sizing tool for determining the dimensions of a piece of art when
it is to be enlarged or reduced.
proportional limit
the greatest stress a material can take without deviation from the linear proportionality
of stress to strain; referred to as Hooke’s law.
propylene glycol
an alcohol used in the manufacture of coatings and inks.
pro rate
to divide, distribute, or asses proptionately.
protective coating
a coating that protects the substrate and the printing on it from abrasion,
sunlight, chemicals, moisture, or any combination of exterior influences;
also refer to overprint varnish.
protocol
the established method for performing an experiment or test.
protoype
a full sized example that serves as a model from which other identical items
can be produced.
prototyping
method of constructing a one-of-a-kind membrane switch with little or no hard
tooling.
protusion
an undesirable raised area on a surface.
proxy
a representative version or sample of a larger image.
proxy image
a low resolution image used in any software program to show the effects of
change without performing transformations on high resoulution files.
prussian blue
a pigment used in ink manufacturing; refer to iron blue.
PS
acroynm for polystyrene.
PSA
acroynm for pressure sensitive adhesive.
PSA primer
preliminary coating applied to a surface to enable an adhesive system to bond
to a substrate.
pseudoplastic
material where the viscosity decreases with increasing shear rate, such as
polymer solutions and emulsions, coating dispersions, paints, adhesives,
varnishes and resins.
psf
acroynm for pounds per square foot.
psi
acroynm for pounds per square inch.
psid
pounds per square inch differential; a pressure difference between two points.
psig
pounds per square inch gage; pressure referenced to ambient air pressure.
psychrometer
a type of hygrometer, that uses the difference in readings between two themometers,
one having a wet bulb ventilated to cause evaporation and the other having
a dry bulb as a measure of atmospheric moisture.
PTA
an abbreviation used to describe a pigment that has been precipitated with
phosphotungstic acid to give it permanance and insolubility.
PTF
acroynm for polymer thick film.
puckering
gathering of fabric due to its tension being less than that of the stitches.
puddle method
a method of developing stencils without complete immersion in the developer.
puff ink
an ink that when heated to a specific temperature for a definite period of
time, achieves a characteristics of three-dimensionality by expansion.
pull
refer to printing stroke.
pull compensation
deliberate distortion digitized into the design to allow for thread pull that
would otherwise cause a one centimeter stitch to shrink to point nine centimeters
due to thread tension.
pulldown
refer to drawdown.
pulp
primary raw material from groundwood, semi-chemical wood, chemical wood (sulphite
and sulphate) and cotton from which paper is made.
pulp type papers
those papers containing ground woods, sulfate and/or sulfate pulps exhibiting
characteristics of high opacity and high strength.
pulsed xenon
a type of actinic illuminate (xenon gas) that provides a very constant output
with a spectral composition resembling sunlight.
punching
changing a visual design into an electronic record to drive an automated embroidery
machine.
purity of color
a color in relation to its composition of pure pigments that form the hue and
its lack of inerts, fillers, bulking agents, and other additives.
push-in lock
a simple, sturdy lock consisting of a predetermined segment of the display
stock so that it can be pushed into position to hold an assembly in position.
PVA
acroynm for polyvinyl acetate solution used in direct-emulsion stencils.
PVAc
acroynm for polyvinyl acetate; also sometimes stated as PVAC.
PVC
acroynm for polyvinyl chloride.
PVC plastisol
refer to plastisol.
PVC stock
plastic sheet materials made from polyvinyl chloride.
PVOH
acroynm for polyvinyl alcohol.
PWB
acroynm for printed wiring board.
pyramid shadow box
a shadow box for displays requiring a strong tilt back.
pyrocon
an instrument used for determining the temperature of the heating plate on
a heat transfer machine.
pyrometer
a meter for registering heat, which may be calibrated in either Fahrenheit
or Celsius scales.
pyrometric cones
small pyramid shapes of ceramic materials used to measure the heat in a kiln
or lehr, designated by numbers as to temperature at which they will deform.
pyrophoric
a chemical substance or mixture that will ignite spontaneously in dry or moist
air below 54.4ºC (130ºF).
pyrophosphate plated circuit boards
circuit boards having been plated in a media of copper potassium pyrophosphate.
pyroxylin
a plastic material of cellulose nitrate, used for coating paper and cloth.
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