Fiber or fibre (from la, fibra, links=no) is a
natural or
artificial
Artificiality (the state of being artificial or manmade) is the state of being the product of intentional human manufacture, rather than occurring naturally through processes not involving or requiring human activity.
Connotations
Artificiality ...
substance that is significantly longer than it is wide.
Fibers are often used in the manufacture of other materials. The strongest engineering materials often incorporate fibers, for example
carbon fiber
Carbon fiber-reinforced polymers (American English), carbon-fibre-reinforced polymers (Commonwealth English), carbon-fiber-reinforced plastics, carbon-fiber reinforced-thermoplastic (CFRP, CRP, CFRTP), also known as carbon fiber, carbon compo ...
and
ultra-high-molecular-weight polyethylene.
Synthetic fibers can often be produced very cheaply and in large amounts compared to natural fibers, but for clothing natural fibers can give some benefits, such as comfort, over their synthetic counterparts.
Natural fibers
Natural fibers develop or occur in the fiber shape, and include those produced by plants, animals, and geological processes.
They can be classified according to their origin:
*
Vegetable fiber
Fiber crops are field crops grown for their fibers, which are traditionally used to make paper, cloth, or rope.
Fiber crops are characterized by having a large concentration of cellulose, which is what gives them their strength. The fibers may b ...
s are generally based on arrangements of
cellulose
Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to many thousands of β(1→4) linked D-glucose units. Cellulose is an important structural component of the primary cell wall ...
, often with
lignin: examples include
cotton,
hemp,
jute,
flax
Flax, also known as common flax or linseed, is a flowering plant, ''Linum usitatissimum'', in the family Linaceae. It is cultivated as a food and fiber crop in regions of the world with temperate climates. Textiles made from flax are known in ...
,
abaca,
piña,
ramie
Ramie (pronounced: , ; from Malay ) is a flowering plant in the nettle family Urticaceae, native to eastern Asia. It is a herbaceous perennial growing to tall; ,
sisal,
bagasse
Bagasse ( ) is the dry pulpy fibrous material that remains after crushing sugarcane or sorghum stalks to extract their juice. It is used as a biofuel for the production of heat, energy, and electricity, and in the manufacture of pulp and building ...
, and
banana
A banana is an elongated, edible fruit – botanically a berry – produced by several kinds of large herbaceous flowering plants in the genus ''Musa''. In some countries, bananas used for cooking may be called "plantains", distinguis ...
. Plant fibers are employed in the manufacture of
paper and
textile (cloth), and
dietary fiber is an important component of human nutrition.
*
Wood fiber
Wood fibres (also spelled wood fibers, see spelling differences) are usually cellulosic elements that are extracted from trees and used to make materials including paper.
The end paper product (paper, paperboard, tissue, cardboard, etc.) dictate ...
, distinguished from vegetable fiber, is from tree sources. Forms include groundwood,
lacebark Lacebark is a common name for several plants, lacebark trees and may refer to:
* lacebark or lace-bark, a textile made from ''Lagetta lagetto'' species
* lacebark, a common name for species in the genus ''Brachychiton''
* lacebark, a common name f ...
, thermomechanical pulp (TMP), and bleached or unbleached
kraft
The second incarnation of Kraft Foods is an American food manufacturing and processing conglomerate, split from Kraft Foods Inc. in 2012 and headquartered in Chicago, Illinois. It became part of Kraft Heinz in 2015.
A merger with Heinz, arra ...
or sulfite pulps. Kraft and sulfite refer to the type of pulping process used to remove the lignin bonding the original wood structure, thus freeing the fibers for use in paper and
engineered wood products such as
fiberboard
Fiberboard (American English) or fibreboard (British English) is a type of engineered wood product that is made out of wood fibers. Types of fiberboard (in order of increasing density) include particle board or low-density fiberboard (LDF), medi ...
.
*
Animal fiber
Animal fibers are natural fibers that consist largely of certain proteins. Examples include silk, hair/fur (including wool) and feathers. The animal fibers used most commonly both in the manufacturing world as well as by the hand spinners a ...
s consist largely of particular proteins. Instances are
silkworm silk,
spider silk
Spider silk is a protein fibre spun by spiders. Spiders use their silk to make webs or other structures, which function as sticky nets to catch other animals, or as nests or cocoons to protect their offspring, or to wrap up prey. They can ...
,
sinew
A tendon or sinew is a tough, high-tensile-strength band of dense fibrous connective tissue that connects muscle to bone. It is able to transmit the mechanical forces of muscle contraction to the skeletal system without sacrificing its ability ...
,
catgut
Catgut (also known as gut) is a type of cord that is prepared from the natural fiber found in the walls of animal intestines. Catgut makers usually use sheep or goat intestines, but occasionally use the intestines of cattle, hogs, horses, mules, ...
,
wool,
sea silk
Sea silk is an extremely fine, rare, and valuable fabric that is made from the long silky filaments or byssus secreted by a gland in the foot of pen shells (in particular ''Pinna nobilis''). The byssus is used by the clam to attach itself to ...
and hair such as
cashmere wool
Cashmere wool, usually simply known as cashmere, is a fiber obtained from cashmere goats, pashmina goats, and some other breeds of goat. It has been used to make yarn, textiles and clothing for hundreds of years. Cashmere is closely associate ...
,
mohair and
angora, fur such as sheepskin, rabbit, mink, fox, beaver, etc.
*
Mineral fiber
Fiber or fibre (from la, fibra, links=no) is a natural or artificial substance that is significantly longer than it is wide. Fibers are often used in the manufacture of other materials. The strongest engineering materials often incorporate ...
s include the
asbestos
Asbestos () is a naturally occurring fibrous silicate mineral. There are six types, all of which are composed of long and thin fibrous crystals, each fibre being composed of many microscopic "fibrils" that can be released into the atmosphere ...
group. Asbestos is the only naturally occurring long
mineral fiber. Six minerals have been classified as "asbestos" including
chrysotile
Chrysotile or white asbestos is the most commonly encountered form of asbestos, accounting for approximately 95% of the asbestos in the United StatesOccupational Safety and Health Administration, U.S. Department of Labor (2007)29 C.F.R.&nbs ...
of the
serpentine class and those belonging to the
amphibole
Amphibole () is a group of inosilicate minerals, forming prism or needlelike crystals, composed of double chain tetrahedra, linked at the vertices and generally containing ions of iron and/or magnesium in their structures. Its IMA symbol is Am ...
class:
amosite
Grunerite is a mineral of the amphibole group of minerals with formula Fe7 Si8 O22( OH)2. It is the iron endmember of the grunerite-cummingtonite series. It forms as fibrous, columnar or massive aggregates of crystals. The crystals are monoclini ...
,
crocidolite
Riebeckite is a sodium-rich member of the amphibole group of silicate minerals, chemical formula Na2(Fe2+3Fe3+2)Si8O22(OH)2. It forms a solid solution series with magnesioriebeckite. It crystallizes in the monoclinic system, usually as long prism ...
,
tremolite,
anthophyllite
Anthophyllite is an orthorhombic amphibole mineral: ☐Mg2Mg5Si8O22(OH)2 (☐ is for a vacancy, a point defect in the crystal structure), magnesium iron inosilicate hydroxide. Anthophyllite is polymorphic with cummingtonite. Some forms of anthoph ...
and
actinolite
Actinolite is an amphibole silicate mineral with the chemical formula .
Etymology
The name ''actinolite'' is derived from the Greek word ''aktis'' (), meaning "beam" or "ray", because of the mineral's fibrous nature.
Mineralogy
Actinolite is ...
. Short, fiber-like minerals include
wollastonite and
palygorskite
Palygorskite or attapulgite is a magnesium aluminium phyllosilicate with the chemical formula ) that occurs in a type of clay soil common to the Southeastern United States. It is one of the types of fuller's earth. Some smaller deposits of this ...
.
*Biological fibers, also known as
fibrous proteins
In molecular biology, fibrous proteins or scleroproteins are one of the three main classifications of protein structure (alongside globular and membrane proteins). Fibrous proteins are made up of elongated or fibrous polypeptide chains which fo ...
or
protein filament
In biology, a protein filament is a long chain of protein monomers, such as those found in hair, muscle, or in flagella. Protein filaments form together to make the cytoskeleton of the cell. They are often bundled together to provide support, s ...
s, consist largely of biologically relevant and biologically very important proteins, in which mutations or other genetic defects can lead to
severe diseases. Instances include the
collagen family of proteins,
tendons,
muscle proteins
Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of muscle ...
like
actin
Actin is a family of globular multi-functional proteins that form microfilaments in the cytoskeleton, and the thin filaments in muscle fibrils. It is found in essentially all eukaryotic cells, where it may be present at a concentration of ov ...
, cell proteins like
microtubules and many others, such as
spider silk
Spider silk is a protein fibre spun by spiders. Spiders use their silk to make webs or other structures, which function as sticky nets to catch other animals, or as nests or cocoons to protect their offspring, or to wrap up prey. They can ...
,
sinew
A tendon or sinew is a tough, high-tensile-strength band of dense fibrous connective tissue that connects muscle to bone. It is able to transmit the mechanical forces of muscle contraction to the skeletal system without sacrificing its ability ...
, and
hair.
Artificial fibers
Artificial or chemical fibers are fibers whose chemical composition, structure, and properties are significantly modified during the manufacturing process. In fashion, a fiber is a long and thin strand or thread of material that can be
knit
Knitting is a method by which yarn is manipulated to create a textile, or fabric. It is used to create many types of garments. Knitting may be done by hand or by machine.
Knitting creates stitches: loops of yarn in a row, either flat or i ...
or
woven into a fabric. Artificial fibers consist of regenerated fibers and synthetic fibers.
Semi-synthetic fibers
Semi-synthetic fibers are made from raw materials with naturally long-chain
polymer structure and are only modified and partially degraded by chemical processes, in contrast to completely synthetic fibers such as
nylon (polyamide) or
dacron
Polyethylene terephthalate (or poly(ethylene terephthalate), PET, PETE, or the obsolete PETP or PET-P), is the most common thermoplastic polymer resin of the polyester family and is used in fibres for clothing, containers for liquids and fo ...
(polyester), which the chemist synthesizes from low-molecular weight compounds by polymerization (chain-building) reactions. The earliest semi-synthetic fiber is the cellulose regenerated fiber,
rayon. Most semi-synthetic fibers are cellulose regenerated fibers.
Cellulose regenerated fibers
Cellulose fiber
Cellulose fibers () are fibers made with ethers or esters of cellulose, which can be obtained from the bark, wood or leaves of plants, or from other plant-based material. In addition to cellulose, the fibers may also contain hemicellulose and li ...
s are a subset of artificial fibers, regenerated from natural
cellulose
Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to many thousands of β(1→4) linked D-glucose units. Cellulose is an important structural component of the primary cell wall ...
. The cellulose comes from various sources: rayon from tree wood fiber,
bamboo fiber
Bamboo textile is any cloth, yarn or clothing made from bamboo fibres. While historically used only for structural elements, such as bustles and the ribs of corsets, in recent years different technologies have been developed that allow bamboo fib ...
from bamboo, seacell from
seaweed
Seaweed, or macroalgae, refers to thousands of species of macroscopic, multicellular, marine algae. The term includes some types of ''Rhodophyta'' (red), '' Phaeophyta'' (brown) and ''Chlorophyta'' (green) macroalgae. Seaweed species such a ...
, etc. In the production of these fibers, the cellulose is reduced to a fairly pure form as a viscous mass and formed into fibers by extrusion through spinnerets. Therefore, the manufacturing process leaves few characteristics distinctive of the natural source material in the finished products.
Some examples of this fiber type are:
*
rayon
*
Lyocell
Lyocell, originally trademarked in 1982 as Tencel, is a form of regenerated cellulose. It consists of cellulose fibers, made by dissolving pulp and then reconstituting it by dry jet-wet spinning. The fiber is used to make textiles for clothing a ...
, a brand of rayon
*
Modal
*
diacetate fiber
*
triacetate fiber.
Historically, cellulose diacetate and -triacetate were classified under the term rayon, but are now considered distinct materials.
Synthetic fibers
Synthetic Synthetic things are composed of multiple parts, often with the implication that they are artificial. In particular, 'synthetic' may refer to:
Science
* Synthetic chemical or compound, produced by the process of chemical synthesis
* Synthetic ...
come entirely from synthetic materials such as
petrochemical
Petrochemicals (sometimes abbreviated as petchems) are the chemical products obtained from petroleum by refining. Some chemical compounds made from petroleum are also obtained from other fossil fuels, such as coal or natural gas, or renewable so ...
s, unlike those artificial fibers derived from such natural substances as cellulose or protein.
Fiber classification in reinforced plastics falls into two classes: (i) short fibers, also known as discontinuous fibers, with a general aspect ratio (defined as the ratio of fiber length to diameter) between 20 and 60, and (ii) long fibers, also known as continuous fibers, the general aspect ratio is between 200 and 500.
Metallic fibers
Metallic fibers can be drawn from ductile metals such as copper, gold or silver and extruded or deposited from more brittle ones, such as nickel, aluminum or iron.
Carbon fiber
Carbon fibers
Carbon fibers or carbon fibres (alternatively CF, graphite fiber or graphite fibre) are fibers about in diameter and composed mostly of carbon atoms. Carbon fibers have several advantages: high stiffness, high tensile strength, high stren ...
are often based on oxidized and via
pyrolysis carbonized polymers like
PAN, but the end product is almost pure carbon.
Silicon carbide fiber
Silicon carbide
Silicon carbide (SiC), also known as carborundum (), is a hard chemical compound containing silicon and carbon. A semiconductor, it occurs in nature as the extremely rare mineral moissanite, but has been mass-produced as a powder and crystal si ...
fibers, where the basic polymers are not
hydrocarbons but polymers, where about 50% of the carbon atoms are replaced by silicon atoms, so-called poly-carbo-
silane
Silane is an inorganic compound with chemical formula, . It is a colourless, pyrophoric, toxic gas with a sharp, repulsive smell, somewhat similar to that of acetic acid. Silane is of practical interest as a precursor to elemental silicon. Sila ...
s. The pyrolysis yields an amorphous silicon carbide, including mostly other elements like oxygen, titanium, or aluminium, but with mechanical properties very similar to those of carbon fibers.
Fiberglass
Fiberglass, made from specific glass, and
optical fiber
An optical fiber, or optical fibre in Commonwealth English, is a flexible, transparent fiber made by drawing glass (silica) or plastic to a diameter slightly thicker than that of a human hair. Optical fibers are used most often as a means t ...
, made from purified natural
quartz, are also artificial fibers that come from natural raw materials,
silica fiber
Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula , most commonly found in nature as quartz and in various living organisms. In many parts of the world, silica is the major constituent of sand. Silica is one ...
, made from
sodium silicate
Sodium silicate is a generic name for chemical compounds with the formula or ·, such as sodium metasilicate , sodium orthosilicate , and sodium pyrosilicate . The anions are often polymeric. These compounds are generally colorless transparent ...
(water glass) and
basalt fiber
Basalt fibers are produced from basalt rocks by melting them and converting the melt into fibers.
Basalts are rocks of igneous origin. The main energy consumption for the preparation of basalt raw materials to produce of fibers is made in natural ...
made from melted basalt.
Mineral fibers
Mineral fibers can be particularly strong because they are formed with a low number of surface defects,
asbestos
Asbestos () is a naturally occurring fibrous silicate mineral. There are six types, all of which are composed of long and thin fibrous crystals, each fibre being composed of many microscopic "fibrils" that can be released into the atmosphere ...
is a common one.
Polymer fibers
* Polymer fibers are a subset of artificial fibers, which are based on synthetic chemicals (often from
petrochemical
Petrochemicals (sometimes abbreviated as petchems) are the chemical products obtained from petroleum by refining. Some chemical compounds made from petroleum are also obtained from other fossil fuels, such as coal or natural gas, or renewable so ...
sources) rather than arising from natural materials by a purely physical process. These fibers are made from:
** polyamide
nylon
** PET or PBT
polyester
** phenol-formaldehyde (PF)
** polyvinyl chloride fiber (PVC)
vinyon
Vinyon is a synthetic fiber made from polyvinyl chloride. In some countries other than the United States, vinyon fibers are referred to as polyvinyl chloride fibers. It can bind non-woven fibers and fabrics. It was invented in 1939.
It has t ...
** polyolefins (PP and PE)
olefin fiber
Olefin fiber is a synthetic fiber made from a polyolefin, such as polypropylene or polyethylene. It is used in wallpaper, carpeting, ropes, and vehicle interiors.
Olefin's advantages are its strength, colorfastness and comfort, its resistan ...
**
acrylic
Acrylic may refer to:
Chemicals and materials
* Acrylic acid, the simplest acrylic compound
* Acrylate polymer, a group of polymers (plastics) noted for transparency and elasticity
* Acrylic resin, a group of related thermoplastic or thermosett ...
polyesters, pure
polyester PAN fibers are used to make
carbon fiber
Carbon fiber-reinforced polymers (American English), carbon-fibre-reinforced polymers (Commonwealth English), carbon-fiber-reinforced plastics, carbon-fiber reinforced-thermoplastic (CFRP, CRP, CFRTP), also known as carbon fiber, carbon compo ...
by roasting them in a low oxygen environment. Traditional acrylic fiber is used more often as a synthetic replacement for wool. Carbon fibers and PF fibers are noted as two resin-based fibers that are not
thermoplastic, most others can be melted.
**
aromatic polyamids (aramids) such as
Twaron,
Kevlar
Kevlar (para-aramid) is a strong, heat-resistant synthetic fiber, related to other aramids such as Nomex and Technora. Developed by Stephanie Kwolek at DuPont in 1965, the high-strength material was first used commercially in the early 1970s ...
and
Nomex
Nomex is a flame-resistant meta- aramid material developed in the early 1960s by DuPont and first marketed in 1967.
Properties
Nomex and related aramid polymers are related to nylon, but have aromatic backbones, and hence are more rigid and m ...
thermally degrade at high temperatures and do not melt. These fibers have strong bonding between polymer chains
**
polyethylene (PE), eventually with extremely long chains /
HMPE (e.g. Dyneema or Spectra).
**
Elastomers can even be used, e.g.
spandex although urethane fibers are starting to replace spandex technology.
**
polyurethane fiber
**
Elastolefin
Elastolefin is a fiber composed of at least 95% (by weight) of macromolecules partially cross-linked, made of ethylene and at least one other olefin
In organic chemistry, an alkene is a hydrocarbon containing a carbon–carbon double bond ...
* Coextruded fibers have two distinct polymers forming the fiber, usually as a core-sheath or side by side. Coated fibers exist such as nickel-coated to provide static elimination, silver-coated to provide anti-bacterial properties and aluminum-coated to provide RF deflection for
radar chaff. Radar chaff is actually a spool of continuous glass tow that has been aluminum coated. An aircraft-mounted high speed cutter chops it up as it spews from a moving aircraft to confuse radar signals.
Microfibers
Invented in Japan in the early 1980s, microfibers are also known as microdenier fibers. Acrylic, nylon, polyester, lyocell and rayon can be produced as microfibers. In 1986, Hoechst A.G. of Germany produced microfiber in Europe. This fiber made it way into the United States in 1990 by DuPont.
Microfiber
Microfiber (or microfibre) is synthetic fiber finer than one denier or decitex/thread, having a diameter of less than ten micrometers. A strand of silk is about one denier and about a fifth of the diameter of a human hair.
The most common ...
s in
textiles refer to sub-denier fiber (such as
polyester drawn to 0.5 denier).
Denier and
Dtex
Textile fibers, threads, yarns and fabrics are measured in a multiplicity of units.
* A fiber, a single filament of natural material, such as cotton, linen or wool, or artificial material such as nylon, polyester, metal or mineral fiber, ...
are two measurements of fiber yield based on weight and length. If the fiber density is known, you also have a fiber diameter, otherwise it is simpler to measure diameters in micrometers. Microfibers in technical fibers refer to ultra-fine fibers (glass or meltblown
thermoplastics) often used in filtration. Newer fiber designs include extruding fiber that splits into multiple finer fibers. Most synthetic fibers are round in cross-section, but special designs can be hollow, oval, star-shaped or
trilobal
In fibers, trilobal is a cross-section shape with three distinct sides. The shape is advantageous for optical reflective properties and is used in textile fibers. Silk fibers' rounded edges and triangular cross section contribute to their luste ...
. The latter design provides more optically reflective properties. Synthetic textile fibers are often crimped to provide bulk in a woven, non woven or knitted structure. Fiber surfaces can also be dull or bright. Dull surfaces reflect more light while bright tends to transmit light and make the fiber more transparent.
Very short and/or irregular fibers have been called fibrils. Natural
cellulose
Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to many thousands of β(1→4) linked D-glucose units. Cellulose is an important structural component of the primary cell wall ...
, such as
cotton or bleached
kraft
The second incarnation of Kraft Foods is an American food manufacturing and processing conglomerate, split from Kraft Foods Inc. in 2012 and headquartered in Chicago, Illinois. It became part of Kraft Heinz in 2015.
A merger with Heinz, arra ...
, show smaller fibrils jutting out and away from the main fiber structure.
[Hans-J. Koslowski. "Man-Made Fibers Dictionary". Second edition. Deutscher Fachverlag. 2009 ]
Typical properties of selected fibers
Fibers can be divided into natural and artificial (synthetic) substance, their properties can affect their performance in many applications. Synthetic fiber materials are increasingly replacing other conventional materials like glass and wood in a number of applications. This is because artificial fibers can be engineered chemically, physically, and mechanically to suit particular technical engineering.
In choosing a fiber type, a manufacturer would balance their properties with the technical requirements of the applications. Various fibers are available to select for manufacturing. Here are typical properties of the sample natural fibers as compared to the properties of artificial fibers.
The tables above just show typical properties of fibers, in fact there are more properties which could be referred as follows (from a to z):
Arc Resistance,
Biodegradable
Biodegradation is the breakdown of organic matter by microorganisms, such as bacteria and fungi. It is generally assumed to be a natural process, which differentiates it from composting. Composting is a human-driven process in which biodegradat ...
, Coefficient of Linear
Thermal Expansion, Continuous Service Temperature,
Density of Plastics,
Ductile
Ductility is a mechanical property commonly described as a material's amenability to drawing (e.g. into wire). In materials science, ductility is defined by the degree to which a material can sustain plastic deformation under tensile stres ...
/
Brittle
A material is brittle if, when subjected to stress, it fractures with little elastic deformation and without significant plastic deformation. Brittle materials absorb relatively little energy prior to fracture, even those of high strength. Bre ...
Transition Temperature, Elongation at Break, Elongation at Yield, Fire Resistance, Flexibility, Gamma Radiation Resistance, Gloss,
Glass Transition Temperature,
Hardness,
Heat Deflection Temperature
The heat deflection temperature or heat distortion temperature (HDT, HDTUL, or DTUL) is the temperature at which a polymer or plastic sample deforms under a specified load. This property of a given plastic material is applied in many aspects of pr ...
, Shrinkage,
Stiffness,
Ultimate tensile strength,
Thermal Insulation,
Toughness,
Transparency, UV Light Resistance, Volume
Resistivity
Electrical resistivity (also called specific electrical resistance or volume resistivity) is a fundamental property of a material that measures how strongly it resists electric current. A low resistivity indicates a material that readily allows ...
, Water absorption,
Young's Modulus
See also
*
Ceramic matrix composite
In materials science, ceramic matrix composites (CMCs) are a subgroup of composite materials and a subgroup of ceramics. They consist of ceramic fibers embedded in a ceramic matrix. The fibers and the matrix both can consist of any ceramic mate ...
*
Dietary fiber
*
Fiber crop
Fiber crops are field crops grown for their fibers, which are traditionally used to make paper, cloth, or rope.
Fiber crops are characterized by having a large concentration of cellulose, which is what gives them their strength. The fibers may b ...
*
Fiber simulation
Fiber simulation is a branch of mechanics that deals with modeling the dynamics and rheology of fibers, i.e. particles of large aspect ratio length to diameter. Fiber simulations are used to gain a better understanding of production processes i ...
*
Fibers in Differential Geometry
*
Molded fiber
*
Nerve fiber
*
Optical fiber
An optical fiber, or optical fibre in Commonwealth English, is a flexible, transparent fiber made by drawing glass (silica) or plastic to a diameter slightly thicker than that of a human hair. Optical fibers are used most often as a means t ...
References
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Materials
Textiles