Cotton is cheap and very plentiful. It has short, flat fibers, with
a spiral twist, thus giving elasticity and the possibility of being
spun into fine thread. Being in itself very useful and inexpensive and
capable of replacing, to a certain extent, any other fiber, it is used
in very large quantities the world over, and is manufactured into a
great variety of materials. The quality of these materials depends on
the strength of the fibers, the fineness or coarseness of material, the
weave, the color and design, and the adulterations.
Cotton, being cheapest, is not adulterated with any of the other
fibers mentioned, when the material is to be sold as cotton cloth, but
it can be made to appear heavier by the addition of mixtures called
sizing. Starches, gums, dextrine, glue, china clay, as well as other
ingredients in varying proportions, constitute this sizing which may
add a large percent to the weight of the cloth. The spaces between the
threads are filled up and a good finish is given to the cloth, although
the wearing quality is not increased. If present in large quantities
the cloth is greatly reduced in weight and firmness after the first
washing.
Adulterations of this kind can be detected by the feeling, a large
quantity imparting a harshness to the material. In very thin fabrics
the sizing may often be detected by holding the cloth up to the light
when the starch shows between the threads. Washing or thorough boiling
of a sample will show the amount of sizing present.
Another method of adulterating cotton is shown in certain kinds of
dotted swiss. A good swiss has thread dots woven or embroidered in the
cloth. Fig. 1A shows a piece of material sold at the price of a good
swiss, but in this case the dots are merely a heavy paste, printed on
the cloth. Fig. 1B shows the result of continued washing, where the
dots have disappeared, and Fig. 1C, the result of ironing with a hot
iron, which turned the spots brown before the cloth itself is harmed.
Mercerized cotton is a cloth produced by the action of a strong alkali
on cotton fiber rinsed under tension. It is a strong, attractive
material, with good wearing qualities. An imitation of this may be
made by the action of very heavy and very hot cylinders on ordinary
cotton cloth. The mercerized cloth has a high luster which it retains
after many washings while the imitation loses its luster with the first
washing.
Sometimes cotton cloth which has been on the market for some time is
weakened by the action of the chemicals used in bleaching, dyeing or in
the sizing. This may be easily detected by tearing the cloth.
Standard cotton materials such as muslins, organdies, percales,
calicoes and sheeting, differ only in the weight of the material,
fineness of thread, hardness of twist and method of finish. Ginghams
have the thread dyed before weaving and fancy weaves are frequently
used. Duck, denim and some other heavy materials have very hard twisted
threads and are frequently woven with a twill. Silkolene is a trade
name for a fine cotton cloth with a silky finish given after the cloth
is woven.
Mercerized cottons make lustrous materials as poplin, imitation pongee
and numerous attractive house furnishing materials.
India “linon” is entirely cotton, with a fleecy surface on the wrong
side, as is “outing flannel” and “canton flannel”.
Many “tussahs,” “voiles” and “economy linens” and other materials with
rather deceptive names are cotton materials made to imitate silk, wool
or linen.