Floor Covering

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Fragmented carpetof the Hert type,17th century. 1.88 1.60 metres.

Axminster carpetfrom England,1765; in the HenryFrancis du PontWinterthurMuseum,Winterthur,

Axminster carpet, late 18th or early 19th century.

Introduction

material made from textiles, felts, resins, rubber, or other

natural or man-made substances applied or fastened to, or laid

upon, the level base surface of a room to provide comfort,

durability, safety, and decoration. Such materials include both

handmade and machine-made rugs and carpets and

smooth-surfaced floor coverings. Although the words carpet and rug are frequently used interchangeably in referring to textile

floor coverings, in modern usage carpets are fastened to the floor

and usually cover an entire floor area, and rugs are not fastened

and rarely cover the entire floor. Carpets and rugs may be classified as handmade or machine-made. Smooth-surfaced

coverings generally adhere to a subfloor and are manufactured as sheet goods or tiles.

Handmade carpets and rugs are usually made by knotting a

number of pile tufts to a backing structure so that the loose knotends form the pile. Mainly produced in Asia and the East, knotted

types are often given the general name of Oriental carpets and

may be classified according to the country of manufacture, suchas Persian (originating in Iran) or Chinese. Well-known districts or

towns may give their names to the carpets they produce; the

Persian Kermn (Kirman) is an example. Other hand-knotted rugsinclude the Savonnerie rugs of France and the modern rya rugs of

the Scandinavian countries. Handmade rugs woven by thetapestry method, often described as the Aubusson type, for the

French town in which the method was perfected, have a flat or slightly ribbed

surface instead of pile. Hooked rugs are made by drawing yarn or fabric strands

through a basic material so as to form a pile of loops that may be clipped or remain uncut.

Machine-made carpets include such woven types as Axminster

and Wilton, and also tufted, knitted, and flocked types.

Axminsters resemble hand-knotted carpets, but their pile yarn is mechanically inserted and bound and not knotted. Wilton types

may have looped (uncut) or cut pile, with designs formed by

bringing yarns of the desired colour to the surface and burying

the others beneath the surface. Velvet carpeting is made by

looping strands that form the pile over wire strips that are removed as each row of loops is completed. Chenille rugs have

soft, deep pile formed by long, furry strips. The pile of tufted

carpets is formed by tufts inserted into a backing with needles. In

knitted carpets, the backing, locking, and pile yarns are all

looped together. Flocked types are produced by systems in whichadhesives are used to bind fibres or yarns to the backing fabric.

Smooth-surfaced floor coverings include linoleum, rubber floor coverings, cork tile,

Encyclopdia Britannica Article

floor covering

Sandeep Kumar PatelHighlight





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asphalt tile, printed felt base, and the vinyl types. Most are available in varying

degrees of thickness, usually from 1/16 to

3/16 inch, and may have some form of

backing. Although flexible types are available in rolls at least six feet wide, square

tiles are increasingly popular in all types. The various materials differ in their ability to take colour or pattern, and mottled or spatter effects are often achieved by

blending in one or more mixes of the same general composition as the basic material.

History

Early floor coverings

Prehistoric man may have happened upon a method of forming thread from twisted

grass or hair. Evidence obtained from recent excavations near the Caspian Sea

indicates that the shearing of sheep and goats, and the spinning and weaving of the

fibres obtained, was practiced as early as 6000 BC. Before the development of

weaving, fibres were probably interlaced to produce a simple form of plaited basket-work matting, replacing still earlier crude mats made of strands of dry stalksand tendrils.

Findings in burial mounds at Pazyryk in southern Siberia, 2,400 years old, indicate

that furs, leather, woven textiles, and felts were used, not as floor coverings, but as wall hangings. The first true carpets, characterized by pile surfaces, were

probably rough cured skins that early hunters laid on the floors of their crude dwellings. Most carpets still retain the same tough flexible backings and upright

pile, affording protection from cold and hard floors, agreeable to the touch, and

serving a decorative function.

Smooth floorings also have ancient origins. In the Late Bronze Age (16001000 BC) water-worn pebbles were laid as flooring in Crete and also on the Greek mainland.

The Greeks refined the technique between the 6th and the 4th centuries BC, and

ancient decorative pebble mosaics have been found in Greece, Asia Minor, and

Sicily. Such mosaics were also made of marble, serpentine alabaster, some forms ofgranite, and other stones suitable for polishing. Timber flooring, originally used in

rough form for a strictly functional purpose, was eventually made into smooth

boards, and was later used decoratively in parquetry designs.

Carpet and rug weaving

Although the exact origins of carpet weaving have not been determined, it is known

that the Egyptians of the 3rd millennium BC wove carpets for the most part of linen ornamented by sewn on brightly coloured pieces of woollen cloth. Egyptian

influence apparently spread throughout the Middle East and then to Mongolia and

China. Some investigators credit Central Asia, Turkestan, and China with the origination of carpets, and in the early 1950s a rug dating back 2,400 years, made

with Turkish knots, was found in Siberia.

Early Chinese carpets were made of knotted silk pile with backings of wool or

cotton, but the pile of later carpets was made of wool. Wool pile was also used in

Central Asia by early nomadic tribes who acquired it easily in their wanderings.

Nomadic rugs were woven on simple horizontal frames that could be rolled up for






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travelling.

Early looms consisted of two forked branches joined by a crosspiece holding the

suspended warp, or lengthwise threads, through which the weft, or crosswise

threads, were woven. A wooden bar was used to flatten the binding weft threads,

allowing the loose warp ends to stand out to form the luxurious pile. The early weavers used wools in their natural gray, white, cream, fawn, brown, or black

colours, but eventually learned to produce fast colours with dyes made from

vegetable, flower, and insect materials.

During the Middle Ages, Italian merchants imported Oriental rugs to Europe, where

they were usually hung on the walls; Europeans continued to cover their floors with rushes and straw. Moorish weavers were probably taken from Spain in the 13th

century to set up the looms at Aubusson in France. Eleanor of Castile introduced

Spanish rugs to England in 1255, and carpets imported from Turkey in the 15th

century encouraged the development of an English rug-weaving industry.

By 1600 French carpet weavers had formed a strong guild, and in 1608 Henry IV set

up looms in the Louvre. During the reign of Louis XIV, carpet manufacture was

revived at Aubusson, where it had suffered from the religious wars of the 16th

century, and was established at Beauvais, in Normandy. The revocation of the Edictof Nantes, that had guaranteed religious and civil freedom to French Protestants,

drove French and Walloon Protestant artisans into England and Germany, where they contributed to the development of spinning and weaving techniques.

English carpet weavers were chartered at Wilton and Axminster in 1701, and in 1740

the Earl of Pembroke brought weavers from France to perform Brussels and Wilton weaving. At about the same time, carpet weaving was also established at

Kidderminster, and the trade extended to northern England and Scotland. In 1830 a

Parliamentary paper noted that carpet wool comprised one-twenty-eighth of the wool produced in the United Kingdom.

In the 18th century Richard Arkwright and others invented machinery that radically improved textile manufacture and together with the steam engine led to the

development of the power loom, first applied to carpet making in 1839. The

so-called Jacquard mechanism, which employed punched cards to control the warp yarns, gradually began to replace the complicated harness of the hand loom for the

production of designs. The tapestry process of printing patterned carpets was

evolved in Edinburgh in the 1830s, and in 1839 a chenille Axminster process, which

was patented by James Templeton of Glasgow, gave increased colour range to carpet designs.

The U.S. carpet industry began by adapting the British system on a modest scale.

Largely a cottage industry, it was organized by agents who marketed the small

amount produced, until the first half of the 19th century. By 1830, the use of

carpets had become popular throughout the eastern U.S., and factories were being

established in New England, New York, and Pennsylvania. The continued dominance of the U.S. market by British carpets led U.S. manufacturers to encourage the

development of power equipment, and a power loom first appeared in 1841. In 1876

an Axminster loom was invented. This development stimulated the carpet industry

by permitting an unlimited range of colour and design with an economy of pile.

Loom widths increased from the formerly conventional 18, 27, or 36 inches (46, 69, or 91 centimetres), to the broadloom, usually 12, 15, or 18 feet (4, 5, or 6 metres)










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Persian medallioncarpet fromTabrz, early 17th

wide, resulting in large economies in weaving costs and producing larger and more

convenient unseamed areas for laying. After World War II, needle tuftingdeveloped, employing a prewoven backing for the basic construction, and the major

portion of carpeting manufactured in the U.S. was produced by this system. Some

tufted carpet manufacturers even began to produce outdoor carpets and imitation

lawns.

Smooth-surfaced floor coverings

In 1860 Frederick Walton of Great Britain patented a process for making linoleum,

the first widely used smooth-surfaced floor covering. Plain linoleum, without

design, was popular until the mid-1930s, when decorative linoleum was developed. In the 1920s, dark-coloured asphalt sheet and tile materials were developed in the

U.S., made from mixtures of asbestos fibre, mineral fillers, and asphalt, and

although light-coloured resins, not containing asphalt, became available within the

next 10 years, the name asphalt tile persists in the U.S. for this type of flooring. In

the U.K. the term asphalt tile was used for a different product, and the somewhat misleading term thermo-plastic tile was applied to a similar British product. Vinyl

asbestos tiles, containing asbestos fibres, were developed next and introduced at the Chicago World's Fair in 1933, but resin shortages prevented quantity production

until 1948. Vinyl, a newer composition material with a high content of polyvinyl chloride resins, was eventually perfected. The number and variety of

smooth-surfaced floor coverings multiplied after World War II, and plastics had

considerable impact. Although traditional linoleum was still in use, such materials as asphalt, cork, rubber, vinyl asbestos, and the various types of vinyl were

achieving greater popularity. A new development in the 1960s was a type of flooring

applied directly to the area to be covered and allowed to harden; epoxy resins havegenerally been used.

Handmade carpets and rugs

Orientals

Major classifications of Orientals, based on place of origin, include Persians, the largest and most important group;

Turkomans, popular, vividly coloured carpets including

Turkoman, Afghan, and Baluchistan rugs made in Central Asia; bold, geometric patterned Caucasian carpets, from Caucasia

and Transcaucasia; the Turkish Anatolian group, less intricately designed than other Orientals; and the Indian, Pakistani, and

Chinese group, frequently less durable than the other types.








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century; in theTextile MuseumCollection in

Knots used in handmade carpets.

Materials

The availability of excellent materials is probably the factor most responsible for

the origin of carpets in the East. The nomads had access to fibres from their

camels, goats, and sheep; cotton was cultivated in Persia and China, and silk in

China. Nomadic carpet makers often used wool for the warp and weft of a rug foundation fabric, as well as for the pile. Although a variety of materials may be

used in making Oriental rugs, wool is the most important pile fibre, and cotton is

most often used as the base and binder material.

Knots

The pile surface of knotted rugs is formed entirely by the

ends of knotted tufts. The Ghiordes, or Turkish, knot brings both tuft ends to the surface together between two warp

yarns. It is common in the Middle East, especially in Turkey

and the Caucasus. The Sehna, or Persian, knot brings each end of the tuft to the surface separately. It predominates in

Central Asia and the Far East, mainly in Afghanistan, India, Pakistan, Turkestan, and China. In Iran either knot is used,

depending upon the origin or site of the tribe or town

producing the rug.

Looms

The loom employed is upright, consisting of two strong beams connected by two vertical posts to make a steady frame. It is often adjustable for the weaving of different sized carpets and rugs. The weaver is positioned conveniently in

relation to the row of knots being worked either by means of a seat that can be raised, moving him upward, or by winding each completed row of knots onto a

separate cloth beam. The warp, or lengthwise, threads stretched between the

two beams are evenly spaced and regularly spun, assuring that the pile forming

beneath the surface will also be even.

Weaving

The weaver ties his rows of knots forming the pattern, and when an entire row

of pile is knotted, the two, three, or four weft, or crosswise, threads are forced

down by a comb or knife, causing the pile to stand out. Density of pile is about 300 knots to the square inch and a weaver completes about 8,000 per day;

several weeks' work is needed to produce an ordinary carpet, and possibly

months for a more complex one. The weaving instructions required to produce

the desired pattern may be chanted by a Salim or may be provided on a coloured

chart of squared paper.



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Dyestuffs

In olden days, craftsmen used natural dyestuffs, obtaining reds from the roots of

the madder plant; carmine red from cochineal, the bodies of the female Coccus cacti; reddish browns from ox blood; yellow from the reseda plant or from

saffron crocus, vine leaves, and pomegranate skins; and blue from the indigo

plant. Mixtures of certain blues and yellows produced greens; and natural wool

shades produced greys and brown, although nutshells and bark were also used.

Oak apples were often used to produce black, but if their iron oxide content washigh the wool was likely to be damaged; some old carpets today show the most

wear in the black portions. Modern synthetic dyestuffs allow greater flexibility

than these traditional dyes.

Characteristics

Persian rugs have intricate all-over patterns, mainly floral, but sometimes including animal or human figures, often with a central medallion. Colours include soft pastels and muted reds, browns, and blues. The rugs are fringed at

both ends.

Turkoman rugs are woven in geometric designs, employing vivid reds, browns, and greens, and usually have webbed fringes at the ends. Caucasian rugs have

sharply outlined, bold, geometric patterns. Brilliant and strongly contrasting

colours are employed, frequently including reds, yellows, and blues. Turkish rugpatterns have precise, stylized geometric or floral designs, with bright, sharp,

contrasting colours. Indian rugs are made with botanical designs in a naturalistic style and are brilliant in colour. Chinese rug designs include religious symbols.

Designs are usually in blue, and background colours include dulled yellows,

browns, and roses.

Other handmade carpets and rugs

Tapestry weave

Another kind of hand weaving is the tapestry method, wherein the coloured weft

threads, wound upon wooden needles, are threaded around and between the

warp ends, leaving a flat or slightly ribbed surface. Since a tapestry carpet lacks

a tufted pile, it does not have a luxurious texture, even though a fine pitch, the number of warps per inch, can be employed, and the richest and most delicate

effects of design and colour obtained. Carpets of this type have long been made

at Les Gobelins, Paris, Aubusson, and Beauvais in France, and Tournai in

Belgium. The work involved in producing tapestry carpet is slow and requires

great skill; the product therefore is expensive.

Hooked rugs

The origin of the hooked rug is obscure. A rug of this type is made by pulling

narrow strips of wool or cotton cloth or wool yarn, with a tool roughly


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resembling a buttonhook, up through a basic material of coarse linen or burlap.

The loops, approximately 1/2 inch high and the width of from two to four of the

mesh openings in the basic material, are often clipped. Frames of various

designs hold the basic material taut. Frequently the rug is made by pushing, instead of pulling, the loop through the basic material, usually employing a large

threaded needle.

Modern handweaving

It is possible to weave rugs, with or without a pile surface, on hand looms.

Almost any material can be used for hand-weaving, including plastic strips and

some forms of rope. Weaving speed can be increased by the use of a

chain-and-pedal drive similar to that used on bicycles. In modern times, handweaving is mainly limited to design development and study in educational

institutions and to the most costly floor coverings, frequently made to order and

considered fine works of art.

Machine-made carpets and rugs

Early machine processes employed hand or water power to duplicate processes

originally performed completely by hand. The invention of the power loom greatly

reduced the amount of time and labour, and therefore the cost, of carpet manufacture.

Nomenclature and types

Machine-made rugs and carpets take their names from the looms employedWilton,for exampleor the construction method, such as ingrain or Brussels.

Ingrain

After 200 years of use, the ingrain became almost obsolete during the 1930s because of its relatively poor wearing qualities. Also called Kidderminster or

Scotch, it is flat ribbed, reversible, and completely without pile, and usually

could be made with two- or three-ply warp and weft yarns, dyed before

weaving.

Design on the surface of the carpet was easily produced by bringing to the

surface, at the chosen area, the desired colour of the weft; the latter almost

completely formed the surface colouring. Although the warp intruded into the

design, its colour was carefully chosen to blend satisfactorily. The term Venetian

has been applied to lesser grades of ingrain carpet.

Wire-formed piles

Brussels carpet, with uncut looped pile formed by round wires, was first


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introduced about the mid-18th century. Shortly after, Wilton followed with the

development of bladed wires producing a cut pile. Both were capable of producing elaborate pile designs, and the Jacquard device was used with them

from about the 1820s, when it replaced hand selection of coloured pile threads.

Bigelow's power principles were applied to the loom from about 1849. Pile not

used for surface design is woven longitudinally into the body of the backing

fabric. Brussels carpets, woven on the Wilton loom, but with their pile remaininguncut, are no longer sold in large quantities.

Tapestry is a printed pile yarn carpet that may be cut or uncut but must, by its

nature, normally be one pile thread per dent. In order to make a design by a method other than printing yarn, more than one pile yarn per dent (five or six

usually) is used with a jacquard. The term velvet, more common in the United

States, is used to mean cut pile single frame; that is, plain carpet for which

tapestry technique is not used. A velvet carpet is basically one of Wilton type.

The term frame is often used instead of pile thread per dent, and a single frame carpet is therefore a plain carpet with one thread per dent.

Tapestry carpets were invented in Scotland in 1830 but are now virtually

obsolete. Few of them were produced in the main carpet centres

(Kidderminster, West Riding of Yorkshire, and Scotland) after World War II.

Typical high quality Wilton and Brussels carpets contain about 120 tufts per square inch with up to 13 rows per inch. Tapestry, generally up to about 80 tufts

per square inch, but as low as 50, is possible. Velvet may be similar in density to

tapestry, but not necessarily so; it can be made with pile as dense as Wilton if desired.

Wilton carpet can be produced on the face-to-face principle. Two carpets are

simultaneously woven sandwiched one above the other, and the two are then cutapart by a reciprocating blade traversing the loom width. The linear rate of

production is thus almost doubled; Jacquard designs can be produced by this

method.

Loom-formed pile

Axminster carpets, in which all of the pile yarn is effectively used for design(unlike Wilton and Brussels that waste some dead pile yarn by hiding it in the

body of the carpet) include spool, gripper, and chenille.

Spool looms were invented in the United States in 1876, and the gripper

Axminster loom was developed about 1890. The chenille two-stage process was

invented in Glasgow about 1830.

With the first loom, each row of pile is drawn from an individual spool, and two

blades cut away the tufts when woven. On the gripper loom, each tuft is held by

its beak-like gripper and taken from its yarn carrier to the fell of the carpet, the

point at which the warp and weft intersect, after being precisely cut away by a

traversing knife blade. One type of spool-gripper Axminster loom employs spools instead of a jacquard; the tufts are taken from them and woven on the gripper

principle. Chenille pile (from the French word for caterpillar) is formed on the

carpet loom by weaving the fur, or pile yarn, as a weft. The tufts are usually

bound by cotton threads forming a long strand. The fur is woven in the first


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weaving process on normal cloth looms and cut longitudinally into the requisite

patterned strips; pile yarn is woven as weft, and the warp is the cotton bindingthreads. A simple gauze or the lacelike leno weave is used to bind the weft pile

yarn so that the pile does not fall away when the strips are cut, before they can

be woven into the carpet.

Jute weft and cotton warp are common materials for Axminster carpets.

All-wool pile is popular, although nylonwool mixtures and various combinations

of natural and man-made fibres are becoming common. Carpets made of 100

percent man-made fibres are increasing in popularity. Spool and gripper qualities

average about 40 to 50 tufts per square inch, the two extremes being about 30and 60.

Unconventional carpets: tufted, knitted, and bonded

In tufted carpets, the tufts are inserted by means of vertically reciprocating

needles pushing through prewoven backing and are held below the carpet

backing by loopers. The loop pile slips off the loopers, or is severed when cut

pile is desired, as the formed carpet moves away from the looping elements. The rate of pile yarn feed from the creel governs pile height. The variation of

this rate for groups of pile threads is the basis for certain patterned effects

resulting from the inclusion of both high and low pile areas or achieved by alternating two different coloured threads across the full width, emphasizing the

pattern in one colour by hiding the other low-pile colour with higher adjacent loops. Different rates of feed can be obtained by electrical or mechanical

means. In the former, the pattern, in small scale, is placed on a pattern drum,

and feelers touching the pattern areas change the delivery rate of the pile feed roller. Photoelectric means of influencing the delivery rate have also been

devised. The mechanical device pushes down the required pile lengths by means

of a castellated metal plate cut to the required pattern. Other effects can be obtained from fancy or printed yarns, and some tufting machines reciprocate thecarpet widthwise to obtain a longitudinal zigzag effect. Designs including up to

eight colours are possible, with quality almost as satisfactory as in traditional carpets having an equal number of colours.

Quality ranges now vary as much as for traditional carpets, since needle spacingsmay be as close as 12 to the inch, giving the same number of tufts per square

inch as in Wilton. Traditional pile materials are employed, but polypropylene, a

synthetic fibre, is commonly used on prewoven backing. There has also been

some development of nonwoven backings.

Production rates can be many times greater than that of Axminster looms; one

machinery manufacturer has developed a yarn looping technique whereby the

backing is pierced by a needle and the pile is then blown through the resulting

opening. This method increases the rate of production up to about 1,200 rows of

pile per minute. Patterned carpets have been produced mainly in the United States with either cut or loop pile or a combination of both. In warp knitting,

beams are used to feed in the yarn supply; in weft knitting, the yarns are fed

from smaller packages.

A Czechoslovakian Arachne stitch-bonding machine achieves high production

rates with low pile costs, employing a fibrous web stitched on the knitting


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principle with yarns drawn from beams. A German Malipol machine uses knitting

principles to bind pile to a backing fabric, although a later model uses unknitted weft threads instead of backing. Production rates for knitting are higher than for

traditional looms but do not reach the high speeds of modern tufting. The

quality of the materials used and the finished carpet are much like that of the

middle range of traditional carpets. No spectacular growth, however, in the

sales of such carpets has occurred, since there are currently limitations in design, although development work is progressing. Several methods use the

principle of bonding fibres, fibrous webs, or yarns with various adhesives. The

technique imposes design limitations, but the less complicated pile forming

method results in high production rates. The needle loom principle involves a

fibrous lap attached to a base fabric, and another method forms a lap into a loop pile sheet and sticks it to a base fabric. A special finishing operation can

convert the loops into cut pile.

A German device projects positively charged fibres toward a negative pole; the fibres are then stuck to an adhesive-coated backing fabric. A Czechoslovakian

technique makes double, or face-to-face, carpet by looping and bonding a

fibrous web to two backing fabrics; the full layer is then cut into two separate

carpets. A French machine cuts fibres from a sheet and then binds them to a fabric backing, with electrostatic means used to keep the fibres vertical.

Manufacturing methods

Raw material preparation

The warp and weft backing structures of carpets, and the pile yarn

superimposed upon it, made originally from natural fibres, are now mostly synthetic. Backing yarns are frequently made from the lower priced cut-staple

normal or high-tenacity viscose rayons. Selvages of synthetic filaments and pile

yarns are produced from mixtures of cut-staple man-made and natural fibres, the latter primarily wool. Pile yarns composed of the more expensive synthetic

materials are increasingly used, and viscose rayon has been used extensively for less costly carpets. As the use of man-made filament pile yarns has increased,

traditional processing of natural and staple man-made fibres has decreased in

importance.

The preparation of natural fibres for backing and pile yarns involved many labour-consuming operations. Fibres had to be cleansed, often by mechanical

means and a wet treatment. Pile-yarn wools had to be thoroughly scoured, and

cotton fibres also needed special cleaning treatment. Straightening of fibres

prior to spinning was a long-drawn-out process, with spinning often followed by

additional single twisting operations to form ply or cable yarns. In contrast, man-made filament yarns are extruded in clean, continuous, and parallel form,

and the twisting operation is uncomplicated. Backing fabrics are currently made

from fibrilated yarns, consisting of small fibres twisted together, and sliced

narrow tapes are made from sheets of synthetic film.

Selection and preparation of design


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Design creation or selection involves consideration of the range or limitations of

the various methods of carpet manufacture. The number of colours that can be used for Jacquard Wilton and gripper Axminster are limited; spool and chenille

Axminster allow unlimited colour range. Density tends to be greatest for Wilton

carpet, sometimes reaching as high as 130 per square inch.

Spool Axminster designs are made from a chain of spools, with one spool to each

row of pile. There are usually seven threads to the inch across the width, with a

pile yarn length per thread of about 35 feet (11 metres). Spool width varies

according to the loom, the smallest is usually 18 inches (46 centimetres) wide.

The person operating the machine creels all necessary colours for the tufts in a row and winds the full spool, repeating the process until the full set for the

design is made.

Gripper Axminster and Wilton Jacquard looms utilize a perforated card system to

select the required combination of different coloured threads per row of pile.

There is one card per row, punched according to the predetermined design, and

the possible colour choice for each tuft is usually one in five for Wilton and onein eight for gripper Axminster. Planting of several additional colours in the

pile-yarn creel may increase the number of different colours possible in a

design. High- and low-cut and uncut effects are also possible in Wilton carpets.

Normally employed on tufted carpets, the process can be applied to all types.Different pile height effects are produced in tufted carpets by using different

rates of yarn feed, and are sometimes emphasized by alternating the colours andhiding the colour of low pile under adjacent high pile. Mechanical and

photoelectric devices are used to regulate the rate of yarn feed to the tufting

needles.

Construction

The basic structure of traditionally manufactured carpets consists of the backingfabric and the pile, which is bound under and between the weft. Pile is formed

on Axminster looms by inserting weft, with reciprocating needles, across the

warp chain yarns. A central stuffer warp usually separates top from bottom weft. In Jacquard Wilton and Brussels carpet, the pile not used for surface

design effect is concealed between top and bottom weft; Axminster carpet uses all pile yarn for surface effect. Wilton pile is formed by looping the yarn over

wires that project it mechanically across the width of the loom and beneath the

decorative pile yarns. When the wires are withdrawn, they either cut the pile,

forming Wilton, or leave it uncut to form Brussels carpet.

In spool Axminster carpets each row of tufts is inserted and cut away from the

spools. On gripper Axminster looms each tuft is inserted by its individual

beaklike gripper, after being cut away from the carrier. Backing fabrics have

warps held on flanged beams; in Wilton weaving, weft threads wound on cops

are shuttled across the loom. Axminster weft is drawn from large stationary cones at the side of the loom.

Tufted carpets differ basically from traditional types because they have a

prewoven backing into which the tufts are inserted. One unconventional method

of making carpet involves the forming of pile on knitted structures. Another

method involves the application of pile yarns or even undulating webs of fibres


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to backing fabric by means of adhesives. These methods often lack the means

for controlling design.

Finishing

After weaving, carpeting may require machine brushing to remove loose fibre or

yarn, before any correction of processing faults. Traditional carpets have a

separate reparation process, but on tufted carpets, missing pile, the most

common fault, is stitched in by a portable gun operating a reciprocatingneedle. The carpet pile is then sheared to uniform level with cutting blades

similar to those of a wide lawn mower. Steaming of the pile causes it to expand

or burst into an aesthetically enhanced state. Natural back-sizings were

formerly applied to Axminster carpets, and Wilton and Brussels weft threads on

their cops were soaked in sizing. Increasing use of such synthetic backing compounds as polyvinylacetate and different kinds of lattice backings now

produces excellent tuft bind and stiffness.

Other modern finishing processes include mothproofing of wool, often performed

in the dyeing sequence, and application of soil-resistant finishes to man-made pile, rot-proofing, and antistatic treatment.

Reinforcement or screening, particularly used for tufted backing, may employ

adhesives on open structure woven materials, and the use of such cushioning materials as synthetic rubber foam is increasing.

Smooth-surfaced floor coverings

Linoleum

Linoleum is produced by pressing a sheet containing oxidized linseed oil, gums andresins, ground cork or wood flour, and pigments on to a backing, and it is hung in

huge curing stoves to toughen.

Two general types, plain and printed, or inlaid, linoleum, are produced; the latter has a constant pattern throughout its thickness. Different methods are employed to

create various design effects. Thickness ranges from about 1.6 to 4.5 millimetres,

depending upon the traffic expected; a standard width is six feet (two metres), andthe weight in 3.2 millimetres gauge is about 7.6 pounds per square yard (3.5

kilograms per square metre).

Recently developed products are specially hardened to resist indentation. Certain

alkalies and organic solvents, however, will attack linoleum if left in prolonged

contact; staining and discoloration can arise from certain anti-oxidants in tires,

rubber castors, or rubber heels. Linoleum is resilient, warm, unaffected by reasonable floor temperatures, and does not readily support combustion.

Printed felt base

Printed felt base is formed by applying a heavy film of paint to felt saturated with


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asphalt; the felt is sealed at both the top and bottom with one or more layers of

coating before application of paint, preventing discoloration from the paint and leveling the surface. The paint used has low volatility and little flow, dries quickly

in thick layers, and gives high gloss with good wearing properties. Wooden blocks

are used to apply the paint on the base, with several colours being printed

separately. The material is next dried in an oven, with the product hanging from

racks or festooned, and this maturing process requires several days. Rugs or rolls are available in several thicknesses and sizes.

Asphalt tile

The tiles are made from asphalts (25 percent) or synthetic resins, asbestos fibres (25 percent), pigments, and mineral fillers (50 percent). If asphaltic binder is used,

colour is restricted to black, brown, and dark reds. The plasticised resin-based tiles

are much lighter in colour, including blues, reds, yellows, and greens, and some

recently developed tiles have a small amount of vinyl binder, giving brighter,

clearer colours and improved grease resistance. The ingredients are mixed at relatively high controlled temperatures to form a dough, that is then forced through

successive calenders until the required thickness and finish is obtained. The sheet isdie cut when cool, ensuring dimensional stability. Common sizes are nine inches (22

centimetres) by nine inches by 1/8 inch or

1/10 inch (three or two millimetres). The

tiles are resistant to fungal attack, mild acids and alkalies, and oils and grease; and they are suitable for use where floor heat is less than 80 F (27 C). Sweeping and

washing with warm water and soap or detergent keeps them clean; wax or resin emulsion polishes improve their appearance and prolong life.

Vinyl floor coverings

Vinyl asbestos tiles were developed from asphalt tiles. Asbestos fibres, mineral

fillers, and pigments are all bonded together with copolymers of vinyl chloride, or with vinyl acetate. Vinyl resin binders have greater flexibility without requiring

heat treatment prior to installation.

Vinyl sheet coverings are made by calendering from various combinations of vinyl chloride resins, pigments, stabilizers, and fillers. Tiles 9 inches, 12 inches, or 18

inches (23, 30, or 46 centimetres) square can be cut from these sheets; widths vary

from 3 to 6 feet (1 to 2 metres). Sheets can be unbacked or backed with felt, hessian, plastic foam, cork, or fabric. One method adds a coat of vinyl to a backing,

and the surface appearance is influenced by the nature of the backing. Jointless seam welding can usually be applied to vinyl sheeting. A blowing agent can be

added to vinyl paste, producing a foamed back and fully bonded vinyl floor

covering. A thin layer of the paste and agent is spread on the back of a

premanufactured vinyl sheet; these are passed through a heated tunnel causing the

release of a gas from the agent, forming the foam.

An all through flushing in the mix can be used for secondary colour effects. Some

laminated sheets have rotogravure pattern printed with vinyl inks and covered by a

protective layer of transparent vinyl. Backed vinyl sheets can have added coloured

chips, with a final clear coating producing a three-dimensional effect. Embossingallows the addition of a second colour into the resultant depressions, producing an


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inlaid effect.

Rubber floorings

Production figures for this material are comparatively small. Previously made with

natural rubber, it is now produced with synthetic rubber mixed with pigments,

fillers, resins and curing materials, and when sheeted is heat cured. Mottled effectsare available, and thicknesses around two- and three-sixteenths of an inch (three to

four millimetres) are available in tiles up to one foot square or in rolls. It is a

comparatively expensive, excellent wearing flooring, although somewhat

susceptible to grease damage, and is appropriate for use in public buildings where

traffic is heavy.

Cork tiles and carpet

When ground cork is heated, either for long periods or by rapid high-frequency

heating, the granules adhere, creating a resilient mixture that can be formed into

tiles, usually two- to five-sixteenths of an inch thick, and six or nine inches square.

This tile has a comfortable resilient feel and absorbs sound, but appearance and wear properties are only fair.

Cork carpet, although limited in use, can be produced from graded cork granules

and polymerized linseed oil, homogeneously pigmented and calendered on a jute canvas backing.

Epoxy resins

Flooring compositions based on epoxy resins have developed steadily, giving a hard,

chemical-resistant, seamless, and firmly adherent floor covering. The resin and

curing agent must be blended immediately before use; colours and fillers can be added. The comparatively high cost of epoxy-resin systems restricts them

principally to repairing or surfacing existing flooring substrates; e.g., concrete. They frequently employ composition based on a cement aggregate and natural

rubber latex. Polyvinyl acetate may be substituted for rubber latex, and such resinsas acrylic, polystyrene, and styrene-butadiene have also been employed.

Economic aspects

Modern research and development have resulted in improved equipment, processes,

and materials contributing both to increased production and greater product

durability. Although per capita use has increased, greater competition exists. Larger

companies usually have larger facilities for development and expansion than smaller

companies and are more likely to survive any large decrease in profit margins. The heavy capital expenditure required for increasingly sophisticated processes, and the

equipment they require, may accelerate the trend in the developed countries toward

larger groups of floor-covering manufacturers and their suppliers.

Peter Ellis


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MLA Style: "floor covering." Encyclopdia Britannica. Encyclopdia Britannica

Ultimate Reference Suite. Chicago: Encyclopdia Britannica, 2012.

APA Style: floor covering. (2012). Encyclopdia Britannica. Encyclopdia Britannica

Ultimate Reference Suite. Chicago: Encyclopdia Britannica.

To cite this page:

Additional Reading

R.S. BRINTON, Carpets, 2nd ed. (1932), traditional carpet structures and processes described at a basic technical level, including some that are obsolete or obsolescent;

A. CROSSLAND, Modern Carpet Manufacture (1958), a description of carpet processes and

structures, including nonwoven types, with helpful diagrams; B. JACOBS, The Story of

British Carpets (1968), a history of the British carpet industry; P. LIEBETRAU, Orientalske

Taepper i farver (1962; Eng. trans., Oriental Rugs in Colour, 1963), an illustrated treatment of the making and nature of Oriental rugs; G. ROBINSON, Carpets and Other

Textile Floorcoverings, 2nd rev. ed. (1972); short sections on nonwoven carpets; F.

WALTON, The Infancy and Development of Linoleum Floorcloth (1925), a history of

linoleum by its inventor; D.T. WARD, Tufting: An Introduction (1969), on the

development of the tufting process; HEDLEY POINTON (ed.), Carpet Surfaces (1975); E.W.

ALLEN, Adhesives for Flooring, R.F. BRIGGS, Contract Flooring: Its Use, Misuse, andAbuse, W.J. WARLOW, Plastics for Flooring, Their Use and Assessment, and J.G.

BRAMLEY and W.V. WILKINSON, Epoxy Floor Coatings, in Floorcovering Symposium (1965),

papers on major developments and problems in hard floorcovering industry; R.

BEAUMONT, Carpets and Rugs (1924), on the design and manufacture of carpets and rugs, not new but has some relevancy; S.R. COCKETT, An Introduction to Man-Made

Fibres (1966), a general treatment of man-made fibres and their production; R.B.HOLT, Rugs, Oriental and Occidental, Antique and Modern (1901), rug making outlined

in a brief and straightforward manner; E. KORNREICH, Introduction to Fibres and Fabrics,

2nd ed. (1966), a quick introduction to several important basic ideas in textiles; F.J.MAYERS, Carpet Design and Designing (1934), on various aspects of carpet designing;

HENRI MUCHERIE, Du Tapis de Roi au Tapis pour Tous (1966), an illustrated descriptive outline of carpet structures (in French); H. OSSWALD, Die Teppichindustrie, 3rd ed.

(1965), detailed technical coverage of main fields of carpet manufacture (in

German).

Floor Covering

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