RACK- A warp-knitting measure
consisting of 480 courses. Tricot fabric quality is judged by the
number of inches per rack.
RACKED STITCH- A knitting stitch that produces
a herringbone effect with a ribbed back. It is
employed in sweaters for decorative purposes or to form the edge of garments.
The racked stitch
is a variation of the half-cardigan stitch; it is created when one set of
needles is displaced in relation
to the other set.
RACKING- A term referring to the
side-to-side movement of the needles of the needle bed of a knitting
machine. Racking results in inclined stitches and reduced elasticity.
RADIO-FREQUENCY DRYING- Use of radio-frequency
electromagnetic radiation for drying textiles.
The application of RF to wet goods results in the selective heating of the
water, which has a
partial polarity, because the molecule must do work to align in the RF field
causing heat generation
within the water droplets. Non-polar materials, i.e., fabrics, are unaffected.
RF drying in very
uniform and energy efficient when airflow patterns through the dryer are
properly designed
and controlled.
RAILS- The metal bars on which the
spindles of a downtwister are mounted.
RAMIE- A bast fiber similar to flax
obtained from the stalk of a plant grown in China, the U.S., and
Japan.
RANDOM-SHEARED CARPET- A pile carpet with a textured
face produced by shearing some of the
loops and leaving others intact.
RAPIER LOOMS- Looms in which either a double
or single rapier (thin metallic shaft with a yarn
gripping device) carries the filament through the shed. In a single rapier
machine, the yarn is
carried completely across the fabric by the rapier. In the double machine, the
yarn is passed from
one rapier to the other in the middle of the shed.
RATINÉ- 1. A plain-weave, loosely
constructed fabric having a rough, spongy texture which is imparted
by the use of nubby plied yarns. It is made from worsted, cotton, or other
yarns. 2. A variant
of spiral yarns in which the outer yarn is fed more freely to form loops that
kink back on themselves
and are held in place by a third binder yarn that is added in a second twisting operation.
RAVEL- A type of comb or rail with
projecting teeth for separating and guiding warp ends.
RAVELING- The process of undoing or
separating the weave or knit of a fabric.
.
RAW FIBER- A textile fiber in its natural
state, such as silk “in the gum” and cotton as it comes from
the bale.
RAYON FIBER- A manufactured fiber composed
of regenerated cellulose, as well as manufactured
fibers composed of regenerated cellulose in which substituents have replaced
not more
than 15% of the hydrogens of the hydroxyl
groups (FTC definition). Rayon fibers
include yarns and fibers made by the viscose
process, the cuprammonium process, and the
now obsolete nitrocellulose and saponified
acetate processes.Generally, in the
manufacture of rayon, cellulose derived from
wood pulp, cotton linters, or other vegetable
matter is dissolved into a viscose spinning
solution. The solution is extruded into an
acid-salt coagulating bath and drawn into
continuous filaments. Groups of these filaments
may be made in the form of yarns or cut
into staple.
REAMING- Further plying of a two-ply
yarn with a singles yarn. Reaming is not the same as plying
three singles yarns in one operation.
RECONSTITUTED FIBERS- Fibers made from recovered
waste polymer or blends of virgin polymer
and recovered waste polymer.
RECREATIONAL SURFACES- Manufactured surfaces providing
consistent properties, durability,
and special characteristics as needed for the specific application. Included
are artificial
turf, pool decks, indoor-outdoor carpeting, tennis court surfaces, etc. Most
types of constructions
(knit, woven, tufted, and nonwoven), and most polymer types find use in this market.
The polyolefins are particularly prominent in these applications.
REDUCTION CLEARING- The removal of unabsorbed disperse
dye from the surface of polyester
at the end of the dyeing or printing process by treatment in a sodium
hydroxide/sodium hydrosulfite
bath. A surface-active agent may be employed in the process.
REED- A comb-like device on a loom
that separates the warp yarns and also beats each succeeding
filling thread against that already woven. The reed usually consists of a top
and bottom
rib of wood into which metal strips or wires are set. The space between two
adjacent wires
is called a dent (or split) and the warp is drawn through the dents. The
fineness of the reed is
calculated by the number of dents per inch.
REED MARKS- A fabric defect consisting of
warpwise light and heavy streaks in a woven fabric,
caused by bent, unevenly packed, or weak reed wires.
REEL- 1. A revolving frame on which yarn
is wound to form hanks or skeins. 2. The frame on which
silk is wound from the cocoon. 3. A linen yarn measure of 72,000 yards. 4. The large wheel
in a horizontal warper onto which the warp sections are wound in the indirect
system of warping.
5. A spool of large capacity used
to wind yarn or wire.
REELING- In silk fiber production, the
process of unwinding the cocoon.
REFRACTIVE INDEX- . INDEX OF REFRACTION.
REFRACTORY FIBER- Oxide or non-oxide, amorphous
or crystalline, manufactured fiber generally
used for applications at temperatures greater the 1063°C in both oxidizing and nonoxidizing atmospheres,
i.e., Al2O3, ZrO2, Al2O3•SiO2.
REGAIN STANDARD- . STANDARD MOISTURE REGAIN.
REGENERATED CELLULOSE- A material which begins as
cellulose but at some stage in the chemical
processing takes the form of another chemical compound, then appears again in
its completed
state as cellulose. Viscose and cuprammonium rayons are regenerated cellulose.
REINFORCEMENT FABRICS- . GEOTEXTILES.
RELATED SHADES- Colors of similar tone in the
same or different depths.
RELATIVE HUMIDITY- The ratio of the actual vapor
pressure of moisture in air to the
saturation
vapor pressure at ambient temperature.
RELATIVE VISCOSITY- Ratio of the viscosity of the
polymer in solution to that of the solvent expressed
as time of efflux of the solution divided by the time of efflux of the solvent
at constant temperature.
RELAXED YARN- A yarn treated to reduce
tension and produce more uniform shrinkage or torque.
Relaxation produces more uniform dyeing characteristics in regular filament
yarns of nylon
or polyester.
.
RELSET® PROCESS- A process of Richen, Inc., for
continuous heat-setting of carpet or other heavy
yarns. Individual ends are continuously fed into a heat-setting chamber and
withdrawn into
take-up cans or fed to winders.
REPACK ORDER- 1. An order requiring special
packaging, as for export. 2. A small order for a
number of items requiring a breakdown of large cases.
REPEAT- The distance covered by a
single unit of a pattern that is duplicated over and over, measured
along the length of a fabric.
REPELLENCY- The ability to resist wetting
and staining by oils, water, soils, and other materials.
RESIDUAL SHRINKAGE- A term describing the amount of
shrinkage remaining in a fabric after
finishing, expressed as a percentage of the dimensions before finishing.
RESILIENCY- Ability of a fiber or fabric to
spring back when crushed or wrinkled.
RESIN- 1. A general term for solid or
semi-solid natural organic substances, usually of vegetable origin
and amorphous and yellowish to brown, transparent or translucent, and soluble
in alcohol or
ether but not in water. 2. Any of a large number of manufactured products made by polymerization
or other chemical processes and having the properties of natural resins.
RESIN-TREATED- Usually, a term descriptive of
a textile material that has received an external resin
application for stiffening or an internal fiber treatment (especially of cellulosics)
to give wrinkle
resistance or permanent press characteristics.
RESTRAINT SYSTEMS- An end use for textile fibers;
restraint systems are devices such as air bags,
seat belts, and shoulder harnesses for passenger protection in automobile,
trucks, airplanes, etc.
RETARDER- A chemical that, when added to
the dyebath, decreases the rate of dyeing but does not
affect the final exhaustion.
REVERSIBLE BONDED FABRIC- A
bonded structure in which two face fabrics are bonded together
so that the two sides may be used interchangeable. There are limitations to the
fabrics that
may be used because of increased fabric stiffness resulting from bonding.
REVOLVING SPINNING RING- A driven ring that rotates in
the direction of the traveler on a ring
spinning frame. Since both the ring and the yarn package turn when this ring
system is used, productivity
is increased.
RHEOLOGICAL PROPERTIES- The properties of viscous
substances including polymers that
deal with deformation and flow. Includes viscosity and flow rate measurements.
.
RIBBING- A corded effect in a woven
fabric that can be either lengthwise, crosswise, or diagonal.
RIBBON- Narrow fabric made in several
widths and a variety of weaves and used as a trimming.
RIB KNIT- A double-knit fabric in which
the wales or vertical rows of stitches
intermesh alternately on the face and the back. In other words, odd wales
intermesh on one side of the cloth and even wales on the other. Ribknit fabrics
of this type have good elasticity, especially in the width.
RICKRACK- Flat braid in zigzag formation.
It is produced by applying different
tensions to individual threads during manufacture.
RIDGY BEAM- A beam of yarn on which the
ends are not evenly distributed
across the barrel, causing a profile of peaks (ridges) and valleys.
A ridgy beam can give poor removal characteristics.
RING- 1. A narrow band around hosiery
appearing different from the rest of the hose. Principal causes-
variations in yarn size, dye, absorption, or luster. 2. The device that carries the
traveler up and
down the package in ring spinning.
RINGER- 1. On a section beam, ringer is a
term used for one or more filaments that have left the parent
end; as the beam revolves, the filaments continue to unwind, wrapping around
the beam (hence
the word “ringer”). The severity of a ringer is dependent upon the number of
filaments contained
therein at the time the filaments break. 2. In slashing, the term ringer is
often used when an
end breaks on the slasher can, adheres to the can, and continues to wrap around
it. This condition
should not be confused with ringers on the section beam.
RING-SPINNING- A system of spinning using a
ring-and-traveler takeup wherein
the drafting of the roving and twisting and winding of the yarn
onto the bobbin proceed simultaneously and continuously. Ring
frames
are suitable for spinning all counts up to 150’s, and they usually give a
stronger yarn and are more productive than mule spinning frames. The
latest innovation in ring spinning involves the use of a revolving ring
(Also .
REVOLVING SPINNING RING) to increase productivity. Ring
spinning equipment is also widely used to take-up manufactured filament
yarns and insert producer-twist at extrusion.
RIPENING- Hydrolysis of cellulose acetate
after acetylation to obtain the desired acetyl value. This is
generally accomplished by heat and agitation of the acid cellulose acetate
solution under controlled
conditions of time, temperature, and acidity. Rapid ripening is accomplished by
using increased
temperature for the reaction.
.
RISER- In textile fabric designing, a
colored or darkened square on the design paper which indicates
that the warp end is over the filling pick at that point. The opposite of riser
is sinker.
ROLLED ENDS- 1. On a section beam, rolled ends
are adjacent ends that do not unwind parallel
to each
other. Rolled ends can be caused by such factors as uneven tension, ridgy
beams, and static.
2. The ends can also roll behind
the hook reed in slashing and can tangle with each other, resulting
in broken ends and ends doubling.
ROLLER CARD- Generally, any type of card in
which rollers do the carding. Usually this refers
to a woolen card with a main cylinder and four to seven stripper rolls and
worker rolls working
in pairs.
ROLL GOODS- Fabric rolled up on a core
after it has been produced. It is described in terms of weight
and width of the roll and length of the material on the roll.
ROLL LAPPING- A condition in which groups of
fibers attach themselves to the drafting rolls instead
of following the normal path through the drafting system. These fibers cause
the trailing fibers
to wind around the rolls and to bread the end down completely. Cleaning of the
rolls is required
to remove the accumulated fiber.
ROPE- 1. A heavy, strong cord, made from
either natural or manufactured
fibers or from wire, in a wide range of diameters.
Yarns are twisted together to form strands. These strands
are then twisted together in the opposite direction to form
the rope. The fact that the twist directions alternate at different
stages of rope assembly assures that the rope will be twist-stable
and will not kink during use. Also called cord. 2. Fabric in process without weft
tension, thus having the appearance
of a thick rope.
ROPE MARK- A fabric defect consisting of
long, irregular, longitudinal markings on dyed or finished goods. A principal cause is abrasion while wet processing the fabric in rope
form. Rope marks
are often related to overloading of the fabric during wet processing.
ROTOFLEX- A fatigue or endurance test
developed by Goodyear for industrial yarns or cords.
ROT RESISTANCE- The ability of textile
materials to resist physical deterioration resulting from
the action of bacteria and other destructive agents such as sunlight or sea
water.
ROUGH- A fabric condition in which the
surface resembles sandpaper. Principal causes are the shuttle
rebounding in the box, jerky or loose shuttle tension, an incorrectly timed harness,
and wild
twist in the filling.
ROVING- 1. In spun yarn production, an
intermediate state between
sliver and yarn. Roving is a condensed sliver that has
been drafted, twisted, doubled, and redoubled. The product
of the first roving operation is sometimes called slubbing.
2. The operation of producing
roving (. 1). 3. In the
manufacture of composites, continuous strands of parallel
filaments.
ROVING FRAME- A general name for all of the
machines used to
produce roving, different types of which are called slubber,
intermediate, fine, and jack. Roving frames draft the
stock by means of drafting rolls, twist it by means of a flyer,
and wind it onto a bobbin.
ROWS- In pile floor covering, the
average number of tufts or loops per inch in the warpwise direction.
RUBBER FILAMENT- A filament extruded from
natural or synthetic rubber and used as the core of
some elastic threads.
RUNNER- A break in the yarn of a knit
fabric that causes the stitch to “run” along the needle line
(wale) in a vertical direction. (Also . END OUT.)
RUNNER LENGTH- In knitting, the number of
inches of yarn from a warp to make one rack of fabric.
RUN-PROOF- A knitted construction in which
the loops are locked to prevent runs.
RUN-RESISTANT- A type of knitting stitch that
reduces runs.
.