Encyclopedia of Global Resources part 131 pdf

Background All textiles are made through the use of fibers: thin strands of natural or artificial material.. All knitted and woven textiles are made from yarn, while fibers alone are use

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dioxide are added to extensively altered olivine- or

pyroxene-rich igneous rocks, and when water and

sil-ica are added to altered carbonate rocks, talc forms

Talc is also found in crystalline schists The mineral is

found mostly in mountainous regions, with China,

South Korea, and Japan as the chief sources

His-torically, the Pyrenees Mountains of France were a

major source of talc and contributed to the beginning

of the cosmetic’s industry in that country

History

Talc has been used since ancient times for carved and

engraved ornaments and utensils American Indians

used steatite for making bowls, pots, and stoves, and

Eskimos used it for sculptures Talc has become an

im-portant ingredient in many commercial products

Obtaining Talc

Generally, talc is obtained through open-pit mining

techniques In his book Functional Fillers for Plastics

(2005), Marino Xanthos outlines the

seven-to-eight-step process for obtaining talc through open-pit

min-ing First, the overburden is removed, thus exposing

the talc The talc is then shoveled out of the mine in order to be crushed Then it is categorized by bright-ness and content The talc is ground to break it down further For most talc this is the final procedure How-ever, high-grade talcs, such as those used in the phar-maceutical industry, require treatment with various chemical compounds

Uses of Talc

In the ceramics industry, talc is used in tableware, electrical porcelain, and glazed wall tiles In paints, talc is used as a extender and as a pigment It is used as

a filler in paper, rubber, insecticides, lubricants, and leather salves In cosmetics, it is used in toilet pow-ders, soaps, and creams, with its extreme softness lead-ing to its use as talcum powder and face powder (With revelations that talc in cosmetics might be linked to lung, ovarian, and skin cancers, many consumers be-gan to avoid talc-containing products.) Massive slabs

of talc are used for acid-proof laboratory tables, sinks, sanitary appliances, acid tanks, electrical switch-boards, mantels, and hearthstones Because it is a poor conductor of electricity and heat, it is used as in-sulation and as a roofing material

Alvin K Benson

See also: Ceramics; Hydrothermal solutions and mineralization; Japan; Magnesium; Metamorphic processes, rocks, and mineral deposits; Minerals, structure and physical properties of; Petrochemical products; Rubber, natural; Silicates; Silicon; United States

Ceramics 31%

Paint 19%

Paper 21%

Plastics 5%

Roofing

8%

Rubber 4%

Other 12%

Commodity Summaries, 2009

Note:

Data from the U.S Geological Survey,

U.S Government Printing Office, 2009.

“Other” includes cosmetics.

U.S End Uses of Talc

Talc is the softest mineral on the Mohs hardness scale (USGS)

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Category: Mineral and other nonliving resources

Where Found

Tantalum is moderately uncommon and is about as

abundant as uranium in the Earth’s crust It is almost

always found in minerals that also contain niobium

and is most commonly found in granite and minerals

derived from granite Tantalum ores are most

abun-dant in Africa and South America The world’s major

producers, in descending order, are Australia, Brazil,

Ethiopia, Canada, and Rwanda Other producers

in-clude Burundi, the Democratic Republic of the Congo,

Nigeria, Uganda, and Zimbabwe

Primary Uses

The most important uses for tantalum are in the

man-ufacturing of capacitors (accounting for more than

60 percent of use in the United States) and in making

corrosion-resistant equipment for chemistry

labora-tories Tantalum is also used in various electronic

devices and in surgical equipment

Technical Definition

Tantalum (abbreviated Ta), atomic number 73,

belongs to Group VB of the periodic table of the

elements and resembles niobium (also known

as columbium) in its chemical and physical

prop-erties It has one naturally occurring isotope

and an atomic weight of 180.95 Pure tantalum

is a hard, dense, silver-gray metal Its density is

16.65 grams per cubic centimeter; it has a melting

point of 2,996° Celsius and a boiling point of

5,427° Celsius

Description, Distribution, and Forms

Tantalum is a fairly rare element resembling

nio-bium It occurs as the oxide in minerals

contain-ing niobium A small amount of the free metal is

found in the former Soviet Union Tantalum is

used in capacitors and chemical equipment

History

Tantalum was discovered by the Swedish chemist

Anders Gustaf Ekeberg in 1802 Because

tanta-lum is so similar to niobium, the two elements

were thought to be identical until 1844, when the

German chemist Heinrich Rose proved they were

different Tantalum was briefly used for lightbulb fila-ments during the early twentieth century until it was replaced by tungsten

Obtaining Tantalum The most difficult problem in obtaining tantalum is

in separating it from the very similar niobium found

in its ores The most common method is known as liquid-liquid extraction The ore is treated with hydro-fluoric acid, which dissolves the tantalum and nio-bium compounds This solution is then treated with

an organic solvent This solvent extracts the tantalum compound at a low level of acidity At a higher acidity the niobium compound is extracted

The tantalum compound obtained by this method may be electrolyzed in a solid form at about 900° Cel-sius to produce pure tantalum powder This powder may also be obtained by treating the tantalum com-pound with metallic sodium The powder may be transformed into tantalum metal by heating it in a vacuum

Electronic components 70%

Machinery 20%

Transportation 6%

Other 4%

Source:

Historical Statistics for Mineral and Material Commodities in the United States

U.S Geological Survey, 2005, tantalum statistics, in T D Kelly and G R Matos, comps.,

, U.S Geological Survey Data Series 140 Available online at

http://pubs.usgs.gov/ds/2005/140/.

U.S End Uses of Tantalum

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Uses of Tantalum

Tantalum is used to manufacture equipment for the

chemical industry because it is extremely strong and

does not react with most chemicals It has also been

used in surgical devices because it does not react with

body tissues Another use is in the manufacture of

ca-pacitors, electronic devices that store electric energy

Tantalum capacitors have a greater ability to store

energy than any other capacitors of the same size and

are thus used in miniaturized components Tantalum

compounds have also been used to manufacture tools

used to cut very hard metals, to manufacture special

kinds of glass, and as catalysts for various chemical

re-actions

Rose Secrest

Web Sites

Natural Resources Canada

Canadian Minerals Yearbook, 1994: Tantalum

http://www.nrcan.gc.ca/smm-mms/busi-indu/cmy-amc/content/1994/60.pdf

WebElements

Tantalum: The Essentials

http://www.webelements.com/tantalum/

See also: Granite; Metals and metallurgy; Niobium;

Oxides; Tungsten

Tar sands See Athabasca oil sands;

Oil shale and tar sands

Taylor Grazing Act

Categories: Laws and conventions; government

and resources

Date: 1934

In the early 1930’s, with much of the federal land in

the West suffering from overgrazing and drought, the

Taylor Grazing Act imposed regulations on the use of

the remaining public domain of the American West.

Background

With the United States in the throes of the Great

Depression, the public lands of the American West

suffered from severe drought and overgrazing As Congressman Edward Taylor of Colorado warned his colleagues, “We are rapidly permitting the creations

of small Sahara Deserts in every one of the Western states today.” Until 1934, Western stockmen grazed animals on federal lands without the need of permis-sion and regulation

In the laissez-faire economic atmosphere of the late 1920’s, President Herbert Hoover’s Commission

on the Conservation and Administration of the Public Domain had recommended that the remaining pub-lic domain be turned over to the states with the fed-eral government retaining title to minfed-eral lands Soon the Depression intervened, however, and concerned westerners channeled their energies into working with federal bureaucrats to shape an acceptable plan for managing those millions of acres of federal lands outside the purview of the National Park Service, Na-tional Forest Service, and other federal agencies The plan was named after Taylor, whose home dis-trict in western Colorado contained a high percentage

of federal land If a veteran congressman such as Taylor could see the benefit of federal regulation, most west-erners could also Even old stockmen who had previ-ously opposed the federal presence as a matter of prin-ciple gave grudging approval to Taylor’s legislation

Provisions The bill ended the free use of the public domain Homesteading would no longer be permitted Thirty-two million hectares of western land would be given to

a new federal agency, the U.S Grazing Service, under the Department of the Interior Local grazing districts were established, and policies would be set by the ranchers themselves Users would pay a nominal fee

to rent the land for ten-year periods, with a portion of the proceeds going to support conservation projects

Impact on Resource Use The Taylor Grazing Act firmly upheld the economic status quo in the public-land West by ordering that

“preference” be given in the issuance of grazing per-mits to “landowners engaged in the livestock busi-ness” and those living near or in the grazing district

In 1936, the act was amended, increasing the total acreage under its domain to 58 million hectares Be-cause the Taylor Grazing Act was founded and ad-ministered by westerners during an era of economic duress, its implementation was relatively free of con-troversy, but several critics of its authority soon

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peared Senator Pat McCarran, a Nevada Democrat,

tried to challenge the system of uniform grazing fees

In 1946, Wyoming Republican senator Edward V

Robertson harked back to the Hoover Commission by

calling for a “return” of all federal lands to the states, a

strategy echoed in the late 1970’s by the so-called

Sagebrush Rebellion McCarran and other western

critics of the Grazing Service succeeded in trimming

its budget during World War II and forcing its merger

with the General Land Office in 1946 The new agency,

the Bureau of Land Management, would administer

the public domain in the years ahead

Steven C Schulte

See also: Bureau of Land Management, U.S.; Dust

Bowl; Ickes, Harold; Public lands; Sagebrush

Rebel-lion

Tellurium

Category: Mineral and other nonliving resources

Where Found

Tellurium is uncommon but widely distributed in the

Earth’s crust It has been found in small amounts as an

uncombined element but is most often found in

vari-ous compounds These compounds occur in sulfide

deposits or in ores of gold, copper, and lead

Primary Uses

Tellurium is used in small amounts to improve the

properties of other metals Tellurium compounds are

used to manufacture thermoelectric devices

Technical Definition

Tellurium (abbreviated Te), atomic number 52,

be-longs to Group VIA of the periodic table of the

ele-ments and resembles selenium in its chemical and

physical properties It has eight stable isotopes and an

average atomic weight of 127.6 Pure tellurium exists

as brittle, silver-white crystals or as a dark gray or

brown powder Its density is 6.24 grams per cubic

cen-timeter; it has a melting point of 449.8° Celsius and a

boiling point of 989.9° Celsius

Description, Distribution, and Forms

Tellurium is a widely distributed element resembling

selenium It usually occurs in compounds with

cop-per, lead, silver, gold, iron, or bismuth The most im-portant sources of tellurium are ores mined for cop-per, lead, and gold The most important producers of tellurium are Canada, the western United States, and Peru Tellurium is nonrenewable, and investigations into the recovery of tellurium from gold and lead-zinc ores is ongoing

History Tellurium was discovered in 1782 by the Austrian min-ing inspector Franz Joseph Müller von Reichenstein

It was not isolated as a free element until 1798 and not used for practical purposes until the middle of the twentieth century

Obtaining Tellurium Tellurium is usually obtained as a by-product of cop-per production After copcop-per is removed from pro-cessed ore by electrolysis, the remaining material contains tellurium as well as silver, gold, and sele-nium The tellurium is separated out by treating the material with a base, then neutralizing it This pro-duces impure tellurium dioxide This compound can

be purified by repeatedly dissolving it and recrystalliz-ing it Free tellurium metal may be obtained by elec-trolysis

Uses of Tellurium Tellurium is added to steel to improve its machin-ability and added to copper to create an alloy with good machinability and high electrical and thermal conductivity It also increases the ductility of alumi-num alloys, the hardness and strength of tin alloys, and the resistance to corrosion of lead alloys Rubber may be treated with tellurium to improve its aging and mechanical properties Tellurium has also been used alone or with platinum as a catalyst for chemical reac-tions

Tellurium compounds are used in thermoelectric devices Lead telluride is used to make devices that produce electricity when heated Bismuth telluride is used to manufacture devices that transfer heat when electricity passes through them

Tellurium is most important as a steel additive and secondarily as an alloy in copper (to improve its machinability while maintaining conductivity), lead (to dampen vibration and lessen metal fatigue), and cast iron (to reduce depth of chill) It is also used in photoreceptors, in blasting caps, in thermal cooling devices, and as a catalyst in the production of

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thetic fibers Tellurium has been added to glass and

ceramics to alter the pigments of these products An

increasingly important application is in the

manufac-ture of solar cells, accounting for an increased

de-mand for high-grade tellurium

Although tellurium is a toxic substance, serious

poisonings are rare Symptoms caused by tellurium

include nausea, headache, sleepiness, and dry mouth

The most distinctive feature of tellurium ingestion is a

strong garlic breath odor, which may persist for

sev-eral days Tellurium toxicity rarely requires treatment

Vitamin C has been used to treat the breath odor

Rose Secrest

Web Sites

Natural Resources Canada

Canadian Minerals Yearbook, 2005: Selenium and

Tellurium

http://www.nrcan.gc.ca/smm-mms/busi-indu/cmy-amc/content/2005/50.pdf

U.S Geological Survey

Mineral Information: Selenium and Tellurium

Statistics and Information

http://minerals.usgs.gov/minerals/pubs/

commodity/selenium/

See also: Alloys; Metals and metallurgy; Selenium;

Sulfur

Tennessee Valley Authority

Category: Organizations, agencies, and programs

Date: Established May 18, 1933

The Tennessee Valley Authority, created primarily for

navigation and flood control of the Tennessee River,

soon became the major producer of electricity for, and

spurred the economic growth of, a seven-state area.

Background

The Tennessee Valley Authority (TVA) is an

indepen-dent agency of the executive department of the United

States government Three directors are appointed by

the president for staggered nine-year terms to

admin-ister the agency and its nineteen thousand employees

The main offices are in Knoxville and Chattanooga,

Tennessee

The concept of encouraging economic growth in the southeastern portion of the United States by mak-ing the Tennessee River more navigable began in

1827, more than one hundred years before the estab-lishment of the Tennessee Valley Authority, when Congress appropriated funds to help survey Muscle Shoals on the Tennessee River in northern Alabama Although the canal project that resulted from that survey was a failure, the idea of taming the river was permanently implanted in the minds of southern leaders Almost a century later, in 1913, the next step was taken when Hale’s Bar Dam was completed on the river near Chattanooga, Tennessee This dam tamed a turbulent section of the river nicknamed the Suck When Wilson Dam made Muscle Shoals passable in

1926, the way was prepared for major development of the entire Tennessee Valley The beginning of the Great Depression in 1929 made the need for that de-velopment more acute

George W Norris, a progressive Republican sena-tor from Nebraska, led the drive for public develop-ment of the Tennessee Valley and earned the infor-mal title “father of TVA.” The bill to establish the Tennessee Valley Authority was one of the first prod-ucts of President Franklin D Roosevelt’s New Deal It was passed and signed in May, 1933 The first dam built by the TVA was a storage dam on the Clinch River It was completed in 1936 and named for Sena-tor Norris Charges by private industry that the TVA was unconstitutional were rejected by the Supreme Court in 1939 During World War II, electricity pro-duced by the TVA played a crucial role in manufactur-ing for national defense Facilities at Oak Ridge, Ten-nessee, were a major component of the Manhattan Project, which produced the atomic bomb The facili-ties operated primarily on TVA electricity

Impact on Resource Use The fifty dams operated directly by the TVA have been instrumental in flood control in the Tennessee Valley and in the larger Ohio River and Mississippi River sys-tem The nine dams on the main stream of the Tennes-see River also created a 1,046-kilometer-long naviga-tion channel from Knoxville, Tennessee, to Paducah, Kentucky Electricity is produced by twenty-nine of the dams and by eleven coal-burning steam plants and two nuclear plants operated by the TVA The power is distributed over an area of about 207,000 square kilo-meters TVA lakes provide recreational facilities for about sixty million people each year Fertilizer

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opment, nuclear energy research, conservation of

natural resources, and many other projects have been

part of the work of the Tennessee Valley Authority

Glenn L Swygart

Web Site

Tennessee Valley Authority

http://www.tva.gov/

See also: Coal; Conservation; Electrical power; Floods

and flood control; Hydroenergy; Nuclear energy;

Nu-clear Regulatory Commission; Roosevelt, Franklin D

Textiles and fabrics

Category: Products from resources

The term “textile” is normally used interchangeably

with the terms “cloth” and “fabric.” A textile is a

knit-ted, woven, or nonwoven cloth material The term is

also applied to fiber and yarn intended for fabric

pro-duction Textiles typically use cotton, flax, ramie,

hemp, jute, and other sources of cellulosic plant fiber;

the fur of sheep, goats, llamas, and several other

ani-mals; and fiber from silkworms, gold, silver, and

rub-ber trees.

Background

All textiles are made through the use of fibers: thin

strands of natural or artificial material A fiber is a

threadlike strand, usually flexible, and is capable of

being spun into yarn About forty different fibers are

of commercial importance While textiles are

primar-ily made from yarn, they are also made by felting,

which is the process of pressing steamed fibers

to-gether to make cloth All knitted and woven textiles

are made from yarn, while fibers alone are used

to produce nonwoven cloth The invention of

spin-ning machines and weaving machines during the

In-dustrial Revolution greatly increased production and

boosted the demand for fibers

The textile industry has created a tremendous

di-versity of products available for use in clothes, home

furnishings, and industrial applications These

prod-ucts are fabricated from natural resources, such as

an-imals, plants, and minerals, as well as from synthetic

compounds The major classifications of fibers by

source are natural and artificial Natural fibers are

those fibers found in nature, such as those from ani-mals and plants; textiles represent a major use of the world’s plant and animal resources Artificial fibers are those fibers manufactured in a laboratory

History About 5000 b.c.e., in Egypt’s Nile Valley, the flax plant was grown and processed into a cloth that was used to wrap mummies of Egyptian rulers At this same time

in Iraq, textiles were made from the wool of sheep By about 3000 b.c.e., other areas of early cotton use were Switzerland, India, and Peru China developed silkmaking by using silkworms at this time Textiles

as a commodity used in trade with other countries started around 1700 b.c.e as this product became more developed in Asia, the Middle East, and Africa

In more recent history, the Industrial Revolution had

a profound effect on the making of textiles, and tex-tile manufacturing was established by the early 1900’s

as an industry in many countries of the world

Animal Fibers Examples of animal fibers are the hair of animals such

as sheep, goat, rabbit, fox, deer, llama, alpaca, vicuña, horse, beaver, hog, badger, sable, and camel These are protein fibers The silkworm also produces a pro-tein fiber Sheep’s wool is the major animal fiber This soft, curly hair is usually called wool, or fleece, instead

of hair A layer of wool can be periodically sheared from the animal without ill effect

Plant Fibers

A major plant fiber source is the cellulose from plants Cellulosic fiber can be found in a plant’s leaf, stem/ stalk, seed pod, or fruit, as applicable Piña, from the pineapple plant, is an example of a leaf fiber Flax, jute, ramie, and hemp are fibers taken from a plant’s stem or stalk, also known as bast fibers Cotton and ka-pok are examples of seed pod and fruit fibers Azlon fibers are produced from proteins found in soybeans and corn Cotton and flax are the major plant fibers One plant source that is not cellulosic is sap from the rubber tree, which can be processed into yarn

Mineral Fibers Asbestos is a somewhat minor natural source of fiber material Found in rock deposits, it has been used

to manufacture products such as fire-resistant cloth With the identification of asbestos as a carcinogen, U.S production ceased, and several other nations placed

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similar restrictions on this mineral Examples of

other minerals and materials used to make

fi-bers are gold, silver, iron (in steel), and glass

These materials can be drawn into thin threads

and then used as decoration in garments and

for support (steel mesh in tires, for example)

Fiber Makeup

The textile fabric that one can see and touch is

composed of many individual fibers The

differ-ences between fibers are determined by their

chemical composition and individual unique

structure Molecular combinations of different

elements are called compounds Any particular

(molecular) compound always contains the same

type and number of elements and their atoms

This gives each compound unique

characteris-tics that determine its particular end use as a

tex-tile When many molecules making up a

com-pound are connected to one another in a line,

they form a linear molecule If this linear

mole-cule is very long, it is called a polymer Animal

hair, the living matter of plants, and some

syn-thetic compounds all contain polymers These

long-string linear molecular compounds are the

building blocks of fibers, which can then be

made into fabrics When polymers are formed

synthetically, the process is called

polymeriza-tion

Only a few elements, in different

combina-tions, make up all the natural and artificial fibers in

textiles For example, carbon, hydrogen, and oxygen,

in various combinations, make up all the plant

cellu-losic fibers The protein fibers contain nitrogen as

well Chlorine, fluorine, silicon, and sulfur are other

elements found in some fibers Artificial fibers may be

constructed from natural polymers that have been

re-shaped or from synthesized polymers made through

chemical processes

All fabric fibers have a characteristic length; these

range from less than 1 centimeter to more than 36

me-ters A relatively short fiber ranging from fractions of a

centimeter to a few centimeters is known as a staple

fi-ber A relatively long fiber, measured in meters, is

known as a filament fiber A natural fiber is always

used in the length in which it has grown Artificial

fi-bers, on the other hand, can be made in any length,

regardless of whether they are reshaped or

synthe-sized The end-use application of the artificial fiber

will determine what its optimum length should be

Artificial Fibers After the invention of artificial fibers in the late 1800’s, there was wide-ranging development of artificial fibers

in the 1900’s There are two subgroups of artificial fi-bers: reconstituted or altered fibers made from natural sources and fibers made from chemical compounds Artificial fibers are produced from compounds hav-ing a wide range of chemical composition and inter-nal structure However, this range of products can be broken down into groups of fibers that have similar composition and structure A generic name is given to each of these groups For naturally occurring materials there are six generic families: acetate/triacetate, azlon, glass fiber, metallics, rayon, and rubber For chemi-cally synthesized fibers there are eleven generic fami-lies: acrylic, anidex, modacrylic, nylon, nytril, olefin, polyester, saran, spandex, vinal, and vinyon All these families are legally defined and identified Manufac-turers making any of these products register a trade-mark name (or trade name) for their particular fiber

Julian Hill, a research chemist with DuPont, reenacts the mid-1930’s dis-covery of nylon (Hagley Museum and Library)

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Artificial Fibers from Natural Sources

De-veloped as a substitute for silk, the first artificial fiber

was named rayon around 1925 Wood pulp is the major

cellulose source of raw material used to produce rayon

fiber Cotton linters (a by-product of cotton

produc-tion) are another source These sources are chemically

processed to extract and purify the cellulose In

regen-erating cellulose into rayon, the purified cellulose

un-dergoes several chemical and mechanical treatments

before being forced through a spinneret machine

Ac-etate and triacAc-etate are two other artificial fibers that

are based on cellulose as a raw material

Artificial Fibers from Chemicals Chemically

created fibers are known as synthetic fibers The first

step in synthesis is polymerization Certain general

production techniques are similar for fibers made

from synthesized polymers Initially, chemical

com-pounds are combined in a closed vat called an

auto-clave Solvents are added, or heat and/or pressure is

applied, to melt and polymerize the compounds Next,

this solution is forced through holes in a spinneret, a

device that contains a nozzle similar to a shower

noz-zle Blowing air on the solution as it exits the nozzle,

or directing the spray through chemically altered

water, hardens the solution into filaments This

pro-cess is called spinning

After spinning, the hardened fibers are stretched

by being wound on rollers while under tension This

reduces the diameter of the fiber, simultaneously

making it uniform and stronger Variations of this

general process are made for different materials and

end uses There are differences in the number of

steps taken, the types of raw materials used, the

spin-neret nozzle hole size and shape, and the manner in

which the filaments are hardened

Yarn

Yarn is generally defined as a continuous strand of

fi-bers spun together as a group, which can then be used

to make fabrics In practice, the majority of yarns are

made in one of four ways: twisting a number of (short)

fibers together, twisting a number of (long) filaments

together, laying a number of (long) filaments

to-gether without twist, or twisting or not twisting a single

(long) filament to produce a monofilament (thread)

Yarn should be strong, flexible, and elastic so that it

can be braided, knotted, interlaced, or looped as it is

processed by various methods into a fabric A system

of producing tightly twisted yarns results in worsted

yarn that is firmer and smoother than regular yarn

Yarns are often made by blending two or more differ-ent fibers to combine the strong points of each When

a manufactured yarn is texturized the long, plain, uni-form yarn is changed to exhibit bulk, loft, and three-dimensional appearance Stretchability may also be included Yarns are curled, crimped, and twisted when texturized

Textile Production The major textile production methods are weaving and knitting Minor methods produce braids, nets, lace, tufted carpets, and other products The only fab-rics made which do not use yarn are those nonwoven fabrics made directly from fibers before they are pro-cessed into yarn Felt is the traditional nonwoven product

Textiles can be classified by their weave or struc-ture The value of a textile depends on many factors, primarily the quality of the raw material; the charac-teristics of the fiber/yarn; smoothness, hardness, and texture; fine, medium, or coarse fibers/yarn; density

of yarn twist and density of weave; dyes/colors and pattern; and finishing processes

Woven Fabric

A major method for producing fabrics is weaving, in which yarns are interlaced at right angles to each other This method was used by the ancient Egyptians Weaving continued to be done by hand as a manual la-bor task until machines were developed during the In-dustrial Revolution The invention of the flying shut-tle and the steam-powered loom in the 1700’s were major contributors to automating the weaving pro-cess

Three basic types of weaves are plain, twill, and satin There can be variations within each of these three weaves Besides the type of weave and the yarn types used, another variation of the weaving process is how close together the yarns are interlaced

Knitted Fabric Knitted fabrics are formed by continuously inter-looping one or more yarns The knitting process may have been used to make fabrics as early as the first cen-tury Knitting remained a hand labor skill until the eighteenth century, when powered knitting machines were developed

Various knitting processes within the basic weft knit type include plain knit, purl knit, rib knit, and in-terlock stitch Weft knits are produced by machine

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and by hand The warp knitting process uses a

ma-chine in which many parallel yarns are interconnected

simultaneously to form loops in the lengthwise

direc-tion Within the basic warp type process, tricot

knit-ting and raschel knitknit-ting are two methods used

Spe-cial processes that are variations of the two basic

methods, sometimes in combination with special

yarns, produce double knits, high pile knits, Jacquard

knits, full-fashioned knits, textured knits, stretch knits,

and bonded knits

Finishes

Finishes are the treatments given to fibers, yarns, or

fabrics to improve their basic characteristics The

three types of finishes employed are mechanical

treat-ments, heat treattreat-ments, and chemical treatments It

is common for one or more of these treatments to be

applied to practically every fabric produced They

change the appearance of the product, as in its look

or feel, and/or add a functional characteristic such

as waterproofing or flameproofing Brushes, rollers,

and hammers may be used in mechanical treatments

Heat-setting of thermoplastic material is a common

heat treatment Chemicals such as acids, bases,

bleaches, polymers, and reactive resins are used to

chemically change the characteristics of a material

The aesthetic finishes, by process name, include

bleaching, brushing and shearing, calendering,

car-bonizing, crabbing, decating, fulling, glazing,

mer-cerizing, napping and shearing, scouring, singeing or

gassing, sizing, and tentering The functional-type

fin-ishes make textiles abrasion resistant, antibacterial,

antisoil and antistain, antistatic, durable press

(per-manent press), flame/fire retardant/resistant, moth

repellent, permanently crisp, shrink resistant,

water-proof, water repellent, or wrinkle resistant

Fabric Design

The major elements of fabric design are the visual

(how it looks) and the tactile (how it feels) All colors

can be applied in an unending combination of

pat-terns and designs The feel of the fabric can be varied

by the types of yarn used, the fabrication method, how

the color pattern is applied, and the types of finishes

used Dyeing and printing are two major methods of

applying a pattern, color, or both, to a fabric Dyes can

be applied to fiber, yarn, or fabric Color can be

ap-plied by at least three methods: directly, the discharge

method, and the resist or reserve method Printing is

typically done by methods such as roller printing,

block printing, toiles de Jouy, stencil, screen printing, spray printing, electroplating, and by hand

The Textile Industry The textile industry is dynamic, with new processes, techniques, and methods constantly being developed Sometimes they add to, and sometimes they replace, previous ways of operating The idea of evolution and change can be applied to all parts of the industry, such

as raw material and fiber development; yarn produc-tion technique; fabricaproduc-tion method; finishing technol-ogy; and the printing, dyeing, and design processes The primary goal of all research and development is

to sell a product attractive to consumers Consumer research is an important factor in determining what the public wants, thereby helping to drive and focus the technology in particular directions Federal laws govern textile labeling and product advertising, and the industry has developed voluntary self-regulating product quality and testing standards

Robert J Wells

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