IMBIBITION: A measure of the liquid or
water-holding capacity of a textile material.
IMMEDIATE ELASTIC DEFORMATION: Recoverable
deformation that is essentially
independent
of time, i.e., occurring in (a time approaching) zero time and recoverable in
(a time
approaching)
zero time after removal of the applied load.
IMPACT RESISTANCE: 1. The resistance of a material to
fracture by a blow, expressed in
terms
of the amount of energy absorbed before fracture. 2. In yarn or cord, the ability
to withstand
instantaneous
or rapid rate of loading.
IMPACT STRENGTH: . IMPACT RESISTANCE.
IMPREGNATED FABRIC: A fabric in which the
interstices between the yarns are completely
filled,
as compared to sized or coated material where the interstices are not
completely filled. Not
included
in the definition is a woven fabric constructed from impregnated yarns, rather
than one
impregnated
after weaving.
INDEX OF REFRACTION: Ratio of the velocity of light
in one medium to its velocity in a
second
medium as the light passes from medium to medium. If a medium is crystalline,
the
velocity
may depend on the direction of the light with respect to the crystalline axes
and the
substance
may have several indexes of refraction, i.e., it may be birefringent. (Also .
BIREFRINGENCE.)
INDIGO: Originally, a natural blue vat
dye extracted from plants, especially the Indigofera
tinctoria plant. Most indigo dyes today are synthetic. They are frequently
used on dungarees and
denims.
INDUSTRIAL FABRIC: A broad term for fabrics used
for nonapparel and nondecorative uses.
They
fall into several classes: (1) a broad group including fabrics employed in
industrial
processes
(e.g., filtering, polishing, and absorption), (2) fabrics combined with other
materials to
produce
a different type of product (e.g., rubberized fabric for hose, belting, and
tires; fabric
combined
with synthetic resins to be used for timing gears and electrical machinery
parts; coated
or
enameled fabrics for automobile tops and book bindings; and fabrics impregnated
with
adhesive
and dielectric compounds for application in the electrical industry), and (3)
fabrics
incorporated
directly in a finished product (e.g., sails, tarpaulins, tents, awnings, and
specialty
belts
for agricultural machinery, airplanes, and conveyors). Fabrics developed for
industrial uses
cover a
wide variety of widths, weights, and constructions and are attained, in many
cases, only
after
painstaking research and experiment. Cotton and manufactured fibers are
important fibers
in this
group, but virtually all textile fibers have industrial uses. The names
mechanical fabrics or
technical
fabrics sometimes have been applied to certain industrial fabrics.
INFLATABLE STUCTURES: Structures opened or enlarged
by input of air and, once enlarged,
able to
retain the air to maintain the distended position.
.
INFLOW QUENCH: Cooling air for extruded
polymer filaments that is directed radially inward
across
the path of the filaments. The threadline is completely enclosed in a quench
cabinet in
inflow
quenching.
INITIAL MODULUS: The slope of the initial
straight portion of the stressstrain
curve.
The modulus is the ratio of the change in stress, expressed in
newtons
per tex, grams-force per tex, or grams-force per denier, to the change in
strain expressed
as a
fraction of the original length.
INITIATOR: A chemical added to start a
reaction such as polymerization. Unlike catalysts,
initiators
may be consumed during the reaction.
INSPECTION: The process of examining
textiles for defects at any stage of manufacturing and
finishing.
INSTRON TENSILE TESTER: A high precision electronic
test instrument designed for testing
a
variety of material under a broad range of test conditions. It is used to
measure and chart the
load-elongation
properties of fibers, yarns, fabrics, webbings, plastics, films, rubber,
leather,
paper,
etc. May also be used to measure such properties as tear resistance and
resistance to
compression.
INTAGLIO: 1. Printing style in which the
design is cut into the surface of the cylinder and is
thus
below the surface. 2. A lustrous, brocade pattern knitted in a tricot fabric.
INTENSITY: 1. The amount of energy per unit
(space, charge, time). 2. The brilliance of a
color. 3. The brightness of light.
INTERFACIAL POLYMERIZATION: Polymerization
in which two reactive monomers, each
dissolved
in different solvents that are mutually immiscible, react at the interface
between the two
solutions.
INTERLINING: A padding or stiffening fabric
used in garment manufacture to provide shape
retention.
Interlining is sandwiched between layers of fabric.
INTERMITTENT PATTERN: A pattern occurring in
interrupted sequence.
INTERNAL DYE VARIABILITY: The
change from point to point in dye uniformity across the
diameter
and along the length of the individual filaments. Affects appearance of the
dyed product
and is
a function of fiber, dye, dyeing process, and dyebath characteristics.
INTERNATIONAL GRAY SCALE: A scale
distributed through AATCC that is used as a
comparison
standard to rate degrees of fading from 5 (negligible or no change) to 1
(severe
change).
The term is sometimes applied to any scale of quality in which 5 is excellent
and 1 is
poor.
INTIMATE BLEND: A technique of mixing two or
more dissimiliar fibers in a very uniform
mixture.
Usually the stock is mixed before or at the picker.
INTRINSIC VISCOSITY: Ratio of the specific viscosity
(R.V.-1) of a solution of known
concentration
to the concentration of solute extrapolated to zero concentration. Also called
the
limiting
viscosity number. It is directly proportional to the polymer-average molecular
weight.
IONOMER: A polymer having covalent bonds
between the constituents of the long-chain
molecules
and ionic bonds between the chains.
ISLANDS-IN-THE-SEA: A type of component fiber
described as multipleinterface
or
filament-in-matrix. The “island” are fibrils of one or more polymers
imbedded
in the “sea” (or matrix) consisting of another polymer. The matrix is
often
dissolved away to leave filaments of very low denier per filament. These
.
fibers
have been used in ion-exchange products and in imitation fur products as well
as to
produce
textile products with a different hand.
ISOTACTIC POLYMER: A polymer structure in which
there is a regular spatial or stereo
relationship
from one repeat unit to the next. (Also . ATACTIC POLYMER,
SYNDIOTACTIC
POLYMER, and TACTIC POLYMER.)
ISOTHERM: Constant temperature line used
on graphs of climatic conditions or thermodynamic
relations,
such as pressure-volume relations at constant temperature.
ISOTROPIC: Having the same physical
properties in every direction in the plane of a fabric. It
is
related to the random distribution of fibers in nonwoven manufacture.