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Dyeing And Finishing






=Dyeing.= When a fabric or fiber is impregnated with a uniform color
over its whole surface, it is said to be "simply dyed." On the other
hand, if distinct patterns or designs in one or more colors have been
impressed upon a fabric, it is called printing.

Vegetable dyes were formerly used, but since the coal tar dyes have
been discovered the latter are used entirely. Over fourteen thousand
colors have been produced from coal tar. Different fibers and fabrics
attract dyestuffs with varying degrees of force. Wool and silk attract
better than cotton and linen.

=Wool Dyeing.= The methods of dyeing wool differ considerably from
those employed for cotton and other vegetable fibers. They may be
divided into three parts: piece dyed, cross dyed, and yarn dyed.

Piece goods are those woven with yarns in their gray or natural state,
and then cleansed and dyed in the piece to such colors as are
required. They are woven in plain weaves and in a great variety of
twills--in fact, in all styles of weaves--and are also made on the
Jacquard loom. The principal fabrics in this classification are all
wool serges, cheviots, hopsackings, suitings, satines, prunellas,
whipcords, melroses, Venetian broadcloths, zibelines, rainproof
cloths; nun's veiling, canvases, grenadines, albatrosses, crepes, and
French flannels; silk warp Henriettas, voiles, and sublimes. Whenever
it is possible, it is better to dye textile fabrics in the form of
woven pieces than in the yarn. During the process of weaving it is
impossible to avoid getting yarn dirty and somewhat greasy, and the
scouring necessary to remove this dirt impairs the color used in
weaving. Piece dyeing is the cheapest method of applying color to
textiles. The chief fault of piece dyeing is the danger of cloud
spots, stains, etc., which do not appear in the other two methods.
Then again in the case of thick, closely woven goods the dyestuff does
not penetrate into the fabric, and the interior remains nearly white.

The cloth is dyed by means of passing over a roller into a dye vat.
Small pieces or "swatches" are taken from the ends of the fabric, and
compared with the pattern. For it must be remembered that no two lots
of crude dyes are of equal strength, and the wools and cottons of
different growths and seasons vary greatly, so that the use of a fixed
quantity of dye to a given amount of goods will not always give the
exact shade. In comparing a sample with the pattern the two are placed
side by side below the eyes (reflected light), and then held up to the
light and the eye directed along the surface. A judgment must be
formed quickly, as a prolonged gaze fatigues the eye and renders it
unable to perceive fine shades of difference.

=Cross Dyed.= Cross-dyed goods may be described as fabrics woven with
black or colored cotton warps and wool or worsted filling and
afterwards dyed in the piece. Since cotton has not the same attraction
for dyestuffs as wool it is a difficult task to dye a fabric woven
with cotton and wool so that both fibers will be identical in depth of
color, tone, and brightness. In some cases it is possible to dye a
mixed fabric at a single operation, but the usual process is to dye
the wool in yarn state and then dye the warp a color as near the color
of the wool as possible. In the weaving operation the wool is thrown
to the surface. In another method the warp is dyed and woven with a
white wool or worsted filling, and dyed in the piece with a dyestuff
that will not affect the cotton. In this way the cotton does not take
the wool dye, but retains its original color. This class of work is
generally used in mohair, alpaca, and luster fabrics, because the
natural brilliancy of the luster wool, alpaca, or mohair in the
filling is not impaired as would be the case if the cotton in the
goods were subjected to a cotton-dye bath after being woven. The
principal cloths in this classification are cotton, warp figured
melroses, Florentines, glaces, brilliantines, lusters, alpacas, and
mohairs; rainproof cloths, and fancy waistings, and in these may be
found the same great variety of weaves and patterns that is to be
found in the piece-dyed goods already described.

=Yarn Dyed.= Yarn-dyed goods differ from those previously described in
that they are made of yarns that are dyed before being woven, or yarns
spun from dyed wool. Wool may be dyed in the raw state (fleece),
slubbing, or yarn. Fleece dyeing is preferable for goods intended to
stand friction, and that in spite of wear and tear must preserve their
color. It is preferred for dark colored goods where much friction is
to be encountered, but is seldom used for light colors, since these
would be soiled during subsequent processes of manufacture. In this
case every fiber is colored uniformly all over. The yarn from this
wool and the cloth woven from it are dyed through and through and do
not become grayish or whitish by wear and tear.

Slubbing dyeing is preferred to yarn dyeing, for the dyestuff
penetrates the loosely twisted roving, and if unevenly dyed, the
subsequent operations equalize most thoroughly the irregularities in
color.

Yarn dyeing is especially applicable to checks, plaids, and suitings,
and in their manufacture the drop box loom (a loom with two or more
shuttles) is used. Goods manufactured under this classification
include cotton warp checks and mixtures; all wool homespuns, mixture
coatings and suitings, storm skirtings, rainproof cloths. These goods
are made in a great variety of weaves, the effect in each being
secured by the color and the weave.

Piece-dyed fabrics may be distinguished from yarn-dyed fabrics by
unraveling threads of each kind. In the case of yarn-dyed fabrics the
dyestuff has penetrated through the yarn, while in the case of
piece-dyed fabrics the dyestuff has no chance to penetrate as
completely as the yarn-dyed fabric.

=Textile Printing.= Printed fabrics such as print cloths can generally
be distinguished by observing the back side of the cloth. If the
figure or pattern on the face of the cloth does not penetrate through
to the back but only shows the outline, the fabric has been printed.
Fabrics are printed by coming into contact with rotating rollers on
which the pattern is engraved.

The attraction of cotton for coloring is generally feebler than that
of wool or silk. Few of the natural dyestuffs attach themselves
permanently without use of a mordant. A mordant is a substance which
has an affinity for, or which can penetrate, the fiber to be colored,
and which possesses the power of combining with the dyestuff and thus
forming an insoluble compound upon the fiber. Cotton is dyed in an
unspun state, and also as yarn or spun thread, either in the hank or
skein. Silk is dyed in unspun skeins, although to a considerable
extent it is also dyed in the piece.

=Styles.= Since styles and designs are constantly changing it is
necessary for the mills to meet this demand by producing new styles.
Some of the patterns which are at this time considered to be in the
best style would have appeared much out of date two or three years
ago, while perhaps a few years hence, the patterns which are now
almost obsolete will, with some changes, become the most popular
sellers of the season. As the mill officials or designers are not out
among the trade, they are not in a position to judge what lines or
patterns would most likely appeal to the market. This information is
obtained by the "styler" of the selling house. The styler receives all
the latest foreign samples and fashion papers from abroad, and often
goes or sends his representative to Europe to ascertain what goods,
designs, and colors are taking well over there. The selling agent or
styler then supplies the designing department of the mill with all the
samples, information, and suggestions necessary in getting out the
samples.

=Construction of Cloth.= In reproducing a sample of cloth in the mill
it is necessary that the construction of the cloth be first known,
that is, there must be ascertained the width, warp ends, and picks per
inch, the number or size of the yarn used for the warp, the number
that is used for the filling, and the number of ounces per yard or
yards per pound. Then the interlacings of the threads in the sample
must be picked out in order to get the design or weave on the design
paper, from which the data are obtained for regulating the movement of
the harness or heddles. Design paper is paper ruled by lines into a
number of squares. An imitation of the cloth can be produced on this
paper by showing the interlacings of the warp and filling. This is
done by filling in certain squares with paint, or pencil marks, while
the others are left empty. In practical work it is the general custom
to make a cross with a pencil to indicate the squares that are to be
filled in, thus showing that the warp thread is over the filling
thread at this point. When a square is left blank it shows that the
warp thread is under the filling at this point. When a warp thread is
up on a certain pick, the harness which controls this thread must be
raised on this pick.

=Finishing.= The fabric as it comes from the loom is in an imperfect
condition for use. When worsted fabrics leave the loom they require
but few and simple finishing operations, and in this respect differ
much from woolen cloths, which require elaborate finishing operations.
The finishing processes of woolen and worsted cloths are similar. The
following description of processes and machines gives a clear idea of
the necessary finishing processes for a standard woolen or worsted
cloth; for particular styles of finish the processes must be varied in
accordance with the particular requirements of the style of fabric in
hand.

=Perching.= The fabric as it comes from the loom receives a perching
and measuring inspection at the weave room before leaving for the
finishing room. This examination is to detect quickly such
imperfections as require prompt attention at the loom.

=Burling.= Every knot that has been tied in the threads during
winding, dressing, beaming, and weaving, must be looked for and felt
for during burling, carefully drawn to the surface of the cloth, and
then clipped off with the scissors, leaving the ends long enough so
that no space without a thread will occur. Threads which are found
loose on the face or back of cloth, caused by the weaver having tied
in a broken end, should be cut off and not pulled off. All places
where threads are not woven in are marked so that the sewing-in girl
(mender) can adjust such places. The cloth is subjected to perching
again. It is examined for imperfections, and when these are found,
they are marked with chalk to call the attention of the menders to
such places.

=Mending.= The object of darning or mending is to make all repairs in
the structure of the cloth before the process of fulling. The mender
must have a good eye for colors necessary to produce various effects
and for the interlacing of the threads. More exact work is required
for threadbare fabrics that require little if any finishing afterward,
than in dealing with a face finish fabric, where the nap is to be
raised and will cover many imperfections so that they will never be
noticed in the finished cloth.

=Fulling.= The object of fulling is to render woolen and worsted
goods stronger and firmer in body. Fulling is similar to felting, the
principal object of each being to condense the fibers, thereby
increasing the firmness. Certain varieties of woolens are fulled
nearly one-half their original width and length. The process of
fulling includes three steps: cleansing, scouring, and condensing the
fibers of the cloth. The object of scouring is to get rid of oil used
preparatory to spinning, and to remove from the cloth stains and the
sizing used in dressing the warp. The cloth is first saturated with
hot water and soap, and is then scoured and rubbed between the
slow-revolving rollers of the machine from two to eighteen hours,
according to the character of goods and the amount of shrinkage
desired. The more prolonged the operation, the more the material
shrinks. When sufficiently fulled, the length of cloth is scoured to
free it from soap. This is done with water, warmed at first, but
gradually cooled, until at the end the cloth is worked in cold water.
Next the cloth is stretched uniformly in all directions, so that it
may dry evenly without wrinkles or curls. Sometimes the cloth is
placed in a hot-air chamber to hasten the drying. The fulling or
shrinking is effected by the application of moisture, heat, and
pressure. Every one is familiar with the fact that woolen blankets,
flannels, and hosiery tend to contract with frequent washings, gaining
in thickness and solidity what they lose in elasticity. Such shrinkage
is greatly hastened when they are rubbed vigorously in hot water and
then allowed to cool suddenly. This change is due to the physical
properties of the wool fiber.

Such goods as beavers, kerseys, meltons, and fancy cassimeres are
seldom fulled more than one-sixth of their woven width, while worsted
goods are shrunk but a small fraction of their woven width. The amount
of fulling received is the distinguishing feature of many varieties of
cloth. In the treatment of broadcloth, doeskin, and all nap finished
woolens, the fulling is carried to a point where the fibers become
densely matted, obliterating all traces of the weave and giving the
cloth the appearance of felt.

=Crabbing.= After the cloth has been dried in the hydro extractor,
where it throws off superfluous moisture, it must be stretched full
width for the future finishing processes, and "set" at this width.

Crabbing consists of two operations, first the loosening process, then
the setting process. Goods are run on a cylinder, then passed over
several rolls, and are kept tight so as to avoid wrinkles. The
cylinders are immersed in hot water and the goods are allowed to
rotate in this water for about twenty minutes, after which they are
taken out for one or two hours. They are then returned to the machine
for about twenty-five minutes and are subjected to boiling and also to
additional pressure. The boiling water sets the fabric and the
additional pressure gives the desired finish.

=Tentering.= The object of tentering[14] is to straighten and level
the fabric. After the cloth leaves the tentering machine it has lost
its natural moisture, and is not at all fitted, as far as fiber
condition is concerned, for the napping. To bring it into a fit state
for this operation it is passed through a trough containing a brush
which gives it the desired moisture. It is then ready for napping.

=Napping.= Most cloths at this stage of finishing are more or less
unsightly on account of long and irregular fibers on the surface. A
nap may be raised on the surface of a fabric for various reasons: in
order to render the material warmer, softer, or more pleasant to the
touch, as in the case of blankets and flannels intended to be worn
next to the body; or for the purposes of increasing the durability of
the fabric, as in the case of melton, kersey, broadcloth, and similar
goods; or a nap may be raised with a view to removing all the fiber
from the underlying structure in order to leave the pattern of the
cloth well defined and free from hairiness. The covering of nap over
the surface of the fabric tends to conceal many defects caused by
imperfect yarns and faulty weaving. Coarse, inferior yarns at best
produce an unsightly fabric, but when the cloth constructed of such
threads is finished with a fine, delicate nap the surface takes on a
softer and richer appearance. Not only are the defects in the
structure concealed, but the material is rendered more sightly and
desirable and appears to be more expensive than it really is.

The operation of napping is performed by passing the cloth in a
tightly stretched condition over a revolving cylinder covered with
teasels or steel hooks. These thousands of little hooks scratch the
entire surface of the cloth, opening up the short fibers and covering
the whole with a nap. Since the fibers are of different lengths it is
necessary to brush the fabric vigorously and then pass it through the
shearing machine in order to make an even and uniform length. The
shearing machine acts on the principle of the lawn mower and either
cuts the nap completely or leaves a pile surface. The cloth is cleaned
by passing through a brushing machine.

=Pressing Machine.= The fabric now requires consolidating and lustering,
or "smarting up" in appearance--practically pressing--before it is
forwarded to the warehouse. This is done by passing the cloth over a
pressing roll heated to a high temperature. Having obtained a
satisfactory luster, it is necessary to fix this by winding the cloth on
rollers and allowing dry steam to pass through the piece. This fixes a
permanent luster and finish on the piece and sets it so as to prevent
shrinkage. The cloth is now packed and sent to the jobbers or tailors to
be cut up into suits.

=Theories of Coloring in Textile Design.= The three primary elements
of textile design are weave, combination of form, and blend of colors.
They enter either separately or in connection with each other into
every species of loom effect. Weave relates specifically to the build
or structure of the cloth and is an indispensable factor in any type
of cloth. Schemes of weaves will produce in one operation an even and
firm cloth, decorated with a type of pattern that usually consists of
minute parts but which is pronounced and decided in combination.
Combination of forms is a surface decoration obtained by uniting
straight and curved lines. Color brightens and improves the qualities
of the design. In fact, the discarding of color shades would diminish
the elegance of the design and impoverish its appearance and would
practically destroy the woolen industry. Whether the pattern be
stripe, check, figure, or intermingled effect, it obtains its outline
and detail from methods of coloring adopted. In worsted there is a
larger diversity of weave design than in woolen; but still colors are
very extensively employed to develop effects due to weave and form,
and also to impart a cheerful and lustrous appearance to cloth.

Patterns in dress fabrics, shirtings, and other articles made entirely
of cotton are frequently mere combinations of fancy shades, while
fabrics composed of silk and jute materials, including silk ties,
handkerchiefs, etc.--in fact the cloths in which fancy shades are
used--show that coloring and its combinations in all woven product
embellished with design, are elements which give tone and character to
the styles. Though the cloth may be soft to the touch, substantially
made, of uniform structure, and skilfully finished, yet a lack of
brightness and elegance in coloring so powerfully detracts from the
appearance of the pattern that these qualities alone are not
sufficient.

On subjecting cotton, silk, wool, and worsted goods to inspection,
color is found to have a different tone or cast in each fabric. Fancy
colors in cotton, while decidedly firm and clear in effect, are
non-lustrous, raw, and dull in toning. Silk colorings, on the
contrary, possess both compactness and brilliancy; woolen colorings
have a unique depth and saturation of hue characteristic of the
material employed in the manufacture of woolen goods; while worsted
colorings are bright, definite, and smart in appearance.

These differences are due to the physical properties of the several
fibers. Thus a filament of silk is transparent and shines like smooth
glass when light falls upon it; that of wool is solid and opaque in
the center, but its exterior consists of a multitude of
semi-transparent scales which, when of large dimensions and uniformly
arranged--as in the best qualities of wool--reflect light with a small
amount of dispersion and impart to the woven material a lustrous
aspect. Cotton has no such partially transparent sheath. What light is
reflected is so broken up that the color is poor. Compare three plain
woven crimson textures made of silk, wool, and cotton respectively.
The first literally shines; luster, brilliance, and richness are the
elements of its coloring. Though bright, it lacks that fulness and
depth of color which belongs to the wool product, whose millions of
filaments, closely compounded, all tinted alike, possess a peculiar
bloom and weight of color not to be found either in the silk or cotton
article. Lastly, take the crimson calico. How deficient in warmth and
richness it seems to be, after examining the woolen and silk texture!
It is dull and has a raw and deficient character.

The various methods of employing fancy shades in patterns obtained in
the loom may be briefly summarized:

I. In mixture cloths, for suitings, coatings, etc.

a. By combining or blending various colors of
materials.

b. By combining several classes of twist threads.

II. In plain, twilled, mat, and fancy weave designs for trouserings,
coatings, suitings, jackets, dresses, costumes, flannels, shirtings,
etc.

a. By introducing colors into the warp, forming
stripes.

b. By introducing colors into the filling, producing
spotted patterns.

c. By introducing colors into both warp and filling,
giving checks, broken styles, etc.

III. In figured designs for dresses, vestings, etc.

a. By using one or several series of extra warp yarn.

b. By using one or several series of extra filling.

Dress goods fall naturally into two distinct classes when regarded
from the standpoint of fashion--staples and fancies. Staples are those
fabrics which are made of the same construction year in and year out.
They vary only in coloring to meet the changes of fashion.

The Staples are:

Brilliantines,
Sicilians,
Mohairs,
Imperial Serges,
Storm Serge,
Cheviots,
Panamas,
Batistes,
Taffetas,
Voile,
Nun's Veiling,
Cashmere,
Shepherd Checks.

The Fancies are:

Produced through
Variation of weave,
Variation of color,
Variation of color and weave:
Brocades,
Cuspettes,
Meliores,
Hopsacking, etc.
Coloring includes:
Stripes,
Checks,
Plaids,
Malenges,
Mixtures.

Prior to the factory era our fathers and mothers made homespun clothes
and wore them till they had passed their period of usefulness. The
average consumption of wool at that time averaged not more than three
pounds per capita. As wealth increased the home loom and
spinning-wheel were slowly supplanted by the mill and factory. The
different textile manufacturers at length found that competition was
so keen that it was necessary to adulterate, particularly any fabric
that was popular. The classes of goods that are most adulterated are
the expensive fabrics, those of wool and silk. There are such changes
of fashion in dress at the present day that garments composed of
materials formerly considered good enough are often thrown aside as
old-fashioned when only half worn. Manufacturers cater to the whims
and fancies of people and import to this country foreign styles. The
rapidly changing styles cause people to throw upon the market a great
amount of cast-off clothing only partially worn.

The result is that there is not wool enough to provide the public
with clothing made of new wool. The requirement per capita has risen
to six pounds. The immense amount of fiber in cast-off clothing does
not find its way into the paper mills, but rather into the shoddy
mill, where it is remanufactured into cloth again, or where part of
the fiber is mixed with good wool to make "pure wool" cloth. In other
words, the rapidly changing styles of to-day and the limited supply of
wool are responsible for the wholesale adulteration which is being
practised in modern cloth manufacture. This adulteration furthermore
is becoming more and more difficult to detect by reason of the rapid
improvements made in the finishing processes of cloth manufacture.
Hence the necessity for people to know how and why adulteration
occurs, how it affects prices, and what are the means of detecting it.
Shoddy is considered a legitimate adulteration in woolen and worsted
goods. The following adulterations are not legitimate unless sold as
such:

1. Cotton combed with wool.

2. Thin cotton threads twisted in with worsted during the process of
drawing.

3. Cotton threads of the same color as the wool or worsted used as
filling or warp.

4. Cotton veneered with wool.

5. Cotton threads of the same color as wool used in weaving.





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