HAND: The tactile qualities of a
fabric, e.g., softness, firmness, elasticity, fineness, resilience,
and
other qualities perceived by touch.
HAND-BLOCKED PRINT: A fabric that has been printed
by hand with wooden or linoleum
blocks.
(Also . PRINTING.)
HANG PICK: A pick that is caught on a warp
yarn knot for a short distance which produces a
triangular
hole in the fabric. Hang picks usually result from knots that are tied
incorrectly, shuttle
tension
that is too loose, or harness that is timed too early.
HANK: 1. A skein of yarn. 2. A standard length of
slubbing, roving, or yarn. The length is
specified
by the yarn numbering system in use; e.g., cotton hanks have a length of 840
yards. 3.
A term
applied to slubbing or roving that indicates the yarn number (count); e.g., a
1.5 hank
roving.
HANK ROVING: . HANK.
HARD FIBER: Stiff, elongated fibers
obtained from leaves or stems of plants. Coarse and stiff,
they
are used in matting and industrial products.
HARDNESS: 1. When used in reference to
water, hardness is the total parts per million (ppm) of
calcium
an CaCO3 plus the magnesium expressed as equivalent CaCO3 [ppm hardness (as CaCO3)
= (ppm
Ca x 2.497 + ppm Mg x 4.116)]. 2. Used in reference to pulp to denote the degree of
delignification.
HARD SIZE: A condition found in areas of
fabric where the warp contains an excessive quantity
of
sizing.
HARNESS: A frame holding the heddles in
position in the loom during weaving.
HARNESS CHAIN: A mechanism used to control the
vertical movements of the harness, or
shaft,
on a loom.
HARSH FIBER: Fiber that is rough or coarse
to the touch, but not fused or bonded filaments.
HEAD END: 1. The beginning of a new piece of
fabric in the loom that bears appropriate
identification.
2. A small sample of fabric that
may be submitted to a customer for approval.
HEATHER YARN: A term describing mottled or
melange-type yarns.
.
HEAT RESISTANCE: A property of certain fibers or
yarns whereby they resist degradation at
high
temperature. Heat resistance may be an inherent property of the fiber-forming
polymer or it
may be
imparted by additives or treatment during manufacture. (Also . HEAT
STABILIZED.)
HEDDLE: A cord, round steel wire, or
thin flat steel strip with a loop or eye near the center
through
which one or more warp threads pass on the loom so that the thread movement may
be
controlled
in weaving. The heddles are held at both ends by the harness frame. They
control the
weave
pattern and shed as the harnesses are raised and lowered during weaving.
HELIX ANGLE: 1. The angle formed by the path of
a ply and the major axis in a yarn or tire
cord. 2. The angle between the tangent
to a yarn and the minor axis of the package on which it is
wound.
Also called wind angle.
HEMICELLULOSES: The principal noncellulosic
polysaccharides in wood. Wood contains 28
to 35%
hemicelluloses, the balance being cellulose and lignin.
HEMP: A coarse, durable bast fiber of
Cannabis
sativa found all over the world. Used primarily
for
twines, cordage, halyards, and tarred riggings.
HERRINGBONE: A broken twill weave
characterized by a balanced zigzag effect produced by
having
the rib run first to the right and then to the left for an equal number of
threads.
HESSIAN: A name for burlap used in the
United Kingdom, India, and parts or Europe. (Also
.
BURLAP.)
HETEROFILAMENT: Also called Heterofil. .
BICOMPONENT FIBERS.
HEXAMETHYLENEDIAMINE: 1,6-diaminohexane, (H2N(CH2)6NH2). It is used in the
polymerization
reaction to form nylon 66.
HIGH-BULK YARN: . TEXTURED YARNS.
HIGH DENSITY: A term to describe a material
with heavier than normal weight per unit
volume.
(Also . DENSITY.)
.
HIGHLOFT: General term for a fiber
structure containing more air than fiber. Specifically, a
lofty,
low-density nonwoven structure that is used for applications such as fiberfill,
insulation,
health
care, personal protection and cleaning material.
HIGH-LOW PILE: A pile construction
characterized by the
presence
of two or more pile heights. High-low pile carpets
sometimes
combine looped and cut surface yarns.
HIGH MODULUS: A term that refers to a material
with a higher
than
normal resistance to deformation. (Also . MODULUS.)
HIGH pH FINISH: A finish, basic in nature
rather than acid or neutral, that is applied to yarn or
fiber.
HIGH-SHRINK STAPLE: Staple with a higher degree of
potential shrinkage than regular staple
of the
same generic fiber. When blended with regular staple and treated (in yarn or
fabric form)
to
induce shrinkage, it produces a high degree of bulk in the product.
HIGH-TEMPERATURE DYEING: . DYEING.
HIGH TENACITY: A term to describe a material
with a higher than normal tensile strength.
(Also .
TENACITY.)
HITCH-BACK: . STICKER, 1.
HOLES (TOW): In tow opening processes,
partial or complete filament breakage within a
confined
spread of tow, usually circular or oval in shape. Not to be confused with
splitting or
partial
crimp deregistration, which are linear.
HOLLAND: . SHADECLOTH.
HOLLAND FINISH: A glazed or unglazed finish
containing oil and a filling material. The
finish
is applied to cotton fabrics to make them opaque or semiopaque. The resultant
fabric
resembles
a beetled linen fabric called Holland fabric.
HOLLOW FILAMENT FIBERS: Manufactured, continuous
filament fibers, having voids
created
by introduction of air or other gas in the polymer solution or by melt spinning
through
specially
designed spinnerets.
HOMESPUN: Coarse plain-weave fabric of
uneven yarns that have a handspun appearance.
HONAN: A pongee-type fabric of the
very best Chinese wild silk. Honan is sometimes woven
with
blue edges.
HOOK REED: . REED.
HOPSACKING: A coarse, open, basket-weave
fabric that gets its name from the plain-weave
fabric
of jute or hemp used for sacking in which hops are gathered.
HORIZONTAL FLAME TEST: . FLAMMABILITY TESTS.
.
HORIZONTAL LINE: . RING.
HOT-AIR SHRINKAGE: Generally, the reduction in the
dimensions of a fabric, yarn, or fiber
induced
by exposure to dry heat. Specifically, a fundamental property of fibers.
HOT-HEAD PRESS: A pressing machine capable of
generating high temperatures and
pressures.
Used for pressing and processing permanent-press fabrics.
HOT-MELT ADHESIVE: A solid material that melts
quickly upon heating, then sets to a firm
bond
upon cooling. Use of this type adhesive provides almost instantaneous bonding.
HOUNDSTOOTH: A term describing a
medium-sized broken-check
effect;
the check is actually a four pointed star.
HUCKABACK: A heavy, serviceable toweling
made with slackly
twisted
filling yarns to aid absorption. The cloth has a honeycomb
effect.
HYBRID COMPOSITE: Advanced composite with a
combination
of
different high-strength continuous filaments in the matrix. Also,
composite
in which continuous and staple fibers are used in the same
matrix.
HYBRID FABRIC: Fabric for composite
manufacture in which two or more different yarns are
used in
the fabric construction. This provides design flexibility to meet performance
requirements
and controls cost by permitting some lower priced fibers to be used.
HYBRID YARN: In aerospace textiles, a yarn
having more than one component. (Also .
COMMINGLED
YARN.)
HYDRAULIC ENTANGLEMENT: . HYDROENTANGLING.
HYDROENTANGLING: Process for forming a fabric by
mechanically wrapping and knotting
fibers
in a web through the use of high-velocity jets or curtains of water. (Also .
SPUNLACES
FABRIC.)
HYDROEXTRACTOR: . CENTRIFUGE.
HYDROGENATION: The process of passing hydrogen
into an unsaturated chemical in the
presence
of a catalyst to convert the material to a more saturated state (i.e.,
containing more
combined
hydrogen.)
HYDROLYSIS: A double decomposition reaction
involving the addition of the elements of
water
and the formation of an acid and a base, an acid and an alcohol, or an acid and
phenol.
.
HYDROPHILIC: Having strong affinity for or
the ability to absorb water.
HYDROPHOBIC: Lacking affinity for or the
ability to absorb water.
HYDROSCOPIC: Having the ability to absorb
moisture from the atmosphere. All fibers have
this
property in varying degrees.
HYDROXYL END GROUP: A polymer chain-terminating
(-OH) group.
HYGROSCOPIC: . HYDROSCOPIC.
HYSTERESIS: 1. In tire cord, a measurement of
work lost through heat during dynamic
operation.
2. In tensile testing, loss of
linear recovery following repeated loading and relaxation.