Electrical properties of textile fiber

BGMEA University Of Fashion & Technology
Excellence Through Education
Assignment Submission
Course Code: TEX 2205
Course Title: Textile Testing & Quality Control-I
Assignment Topic: Electrical Properties of Textile Fibers.
Submitted To:
Mr. Md. Anwar Kamal
Lecturer,
Department of TE
Date of Submission: 4th
August, 2020
Topic No – 06
Submitted by:
Md. Nazmul Ahshan Sawon
Student
ID: 182-130-801
Batch: 182, Section: 02
Department of TE

Page I of III
Acknowledgement:
This is the first innovative Assignment topic which is not directly connected to our academic topics. Yes,
this is a part but this topic is too deep about thinking, its helps us to gather new knowledge, gives us the
opportunity for finding new information, to discuss about the details beyond our thinking capacity.
My Assignment topic was ''Electrical Properties of Textile Fiber" this research based content selection was
really so much praiseworthy. And for this reason we are hereby so much grateful to our honorable faculty
and our beloved Mr. Md. Anwar Kamal Sir. We are really so much thankful for giving us that
opportunity for guiding us a new era a new way.
From this group, after completing the experiment we feel proud that we got an extraordinary person like you
for this course (TEX 2205)
We apologies for our unwanted fault that could be occurred in our topics for our misunderstanding about the
topics. We all from our team tried a lot to submit a fruitful and informative Assignment that's said.
“Thank You Sir”

Page II of III
Course Code: TEX2205
Course Title: Textile testing & quality control-1
Assignment Topic NO: 06
Topic: Electrical Properties of Textile Fiber.

Page III of III
Index
Introduction
Textile Material
Fiber
Textile Fiber
Types of Textile Fiber
Natural Fiber
Man-Made fiber
Properties of Textile Fiber
Physical properties,
Chemical properties
Mechanical properties of Textile fiber.
Electrical Properties of Textile Fiber
Factors Affecting Dielectric Properties
Frequency
Moisture
Presence Of Impurities
ELECTRICAL CONDUCTIVITY AND RESISTIVITY
FACTORS AFFECTING FIBRE RESISTANCE:
Moisture
Effect Of Impurities
Effect of Temperature
Polarization and Related Effects:
FACTORS AFFECTING STATIC GENERATION:
Measuring the contact resistance between the electrode and the textile substrate
Measurements of surface resistance of textile sample
Conclusion
Reference

of 38
T o p i c : E l e c t r i c a l P r o p e r t i e s o f T e x t i l e F i b e r s.
S u b m i t t e d T o : M r . M d . A n w a r K a m a l S u b m i t t e d B y : M d . N a z m u l A h s h a n S a w o n
BGMEA University Of Fashion & TechnologyExcellence Through Education
Introduction:
Textile materials have the inherent ability to store electric charges. “Electrifiability” means the ability
of a clothing to generate and retain an electrostatic field of significant strength for a relative long time.
The interest for investigation of the electrical properties of the fibres was generated with the use of
fibres as insulating materials. Later, the resistance and capacity methods were used in instruments to
determine the moisture content and the irregularity of the fiber assemblies. Applications of conductive
textiles are more and more numerous in technical areas and cater to functions such as heating,
conduction, or EMI shielding, prevention of static charges build-up.
Most of the textile and plastic materials are electrical insulators. They accumulate electrostatic charge,
which causes problems such as severe shock, fire, dust accumulation, etc. during processing. The
electrical conductivity is required to dissipate the charges and use of fibres blended with conductive
type of fibres prevents such risk. Low and limiting electrical conduction is required in many practical
applications such as electromagnetic shielding, electrostatic elimination, conveyor belts, aviation/space
suits, dry filtration, carpets etc. For this purpose, various products having reasonably good electrical
conductivity are required.This can be obtained by incorporating metal fillers orcoatingwithsome agent.
The textile materials being flexible and easily workable are the most preferred one in such cases.

of 38
Textile material
Resistivity is a feature of the raw material. It is known the electrical resistivity of a material is an
intrinsic physical property, independent of the particular size or shape of the sample. Resistivity of flat
textilematerialcanbedifferent.Theelectricalresistanceoftextilematerialdepends onthearrangement
of fibres and yarns in textiles makes them, in the majority of cases, not homogeneous and anisotropic
products. It also depends on the geometrical dimensions of the sample and on its structure. Surface
resistance required to determine the surface resistivity of textile material depends on measurement
technique, in particular electrode arrangement on sample surface.
The fabric contains fibres with a coating such as nickel which is stable against corrosion and has a good
shielding value.Thewoven fabric contains 15 g of pure nickelpersquare meter. The technologycombines
highly conductive and corrosive resistant nickel with woven fabric provides to good surface resistance.
Moreover the manufactured electro conductive fabric is flexible and durable. The potential applications
of the textile material are: filters, shielding rooms, antennas, gaskets and components to medicine
applications. Microscopic image of woven fabric taken with Olympus microscope was captured at 7.5×
magnification.

of 38
Fiber
Fiber or fibre (from Latin: fibra) is a natural or man-made substance that is significantly longer than it
is wide. It is defined as one of the delicate, hair portions of the tissues of a plant or animal or other
substances that are very small in diameter in relation to their length. It is a material which is several
hundred times as long as it’s thick.
Fibers are often used in the manufacture of other materials. The strongest engineering materials often
incorporate fibers, for example carbon fiber 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.

of 38
Textile Fiber:
Textile fiber has some characteristics which differ between fibers to Textile fiber. Textile fiber can be
spun into a yarn or made into a fabric by various methods including weaving, knitting, and braiding,
felting, and twisting. The essential requirements for fibers to be spun into yarn include a length of at
least 5 millimeters, flexibility, cohesiveness, and sufficient strength. Other important properties include
elasticity, fineness, uniformity, durability, and luster.
Fig: Textile fiber
Banana fiber is one kind of fiber but it is not a textile fiber. Because it cannot fill up the above
properties. So we can say that all fiber are not textile fiber.
Types of Textile Fiber:
Generally two types of textile fiber:
 Natural fiber.
 Manmade fiber.

of 38

of 38
Natural Fiber:
Natural fibers include those produced by plants, animals, and geological processes. They are
biodegradable over time. They can be classified according to their origin.
A class name for various genera of fibers (including filaments) of:
 Animal (i.e., silk fiber and wool
fiber);
 Mineral (i.e., asbestos fiber);
 Vegetable origin (i.e., cotton
fiber, flax fiber, jute fiber, and
ramie fiber).

of 38
Manmade Fiber:
It is also known as manufactured fiber. Synthetic or man-made fibers generally come from synthetic
materials such as petrochemicals. But some types of synthetic fibers are manufactured from natural
cellulose; including rayon, modal, and the more recently developed Lyocell. A class name for various
genera of fibers (including filaments) produced from fiber-forming substances which may be:
 Polymers synthesized from chemical
compounds, e.g., acrylic fiber, nylon
fiber, polyester fiber, polyethylene fiber,
polyurethane fiber, and polyvinyl fibers;
 Modified or transformed natural
polymers,e.g., alginic and cellulose-based
fibers such as acetates fiber and rayon
fiber; and
 Minerals, e.g., glasses. The term
manufactured usually refers to all
chemically produced fibers to distinguish
them fromthe trulynaturalfibers suchas
cotton, wool, silk, flax, etc.e.g: Glass fiber.

of 38
Properties of textile fiber
We saw three types of properties according to the fiber properties for a textile fiber. There are a lot of
characteristic in the textile fibers. But it is characterized as three basic characterization.
They are
1. Physical properties,
2. Chemical properties
3. Mechanical properties of Textile fiber.
 Physical Properties :
i. Fiber length:
In physical properties the most important is the fiber length on which the quality of yarns depends. For
cotton if fiber length increases the quality of yarns will be good, but this is just opposite for wool. In jute
the fiber length is too long that sometimes the fibers are cut into small pieces.
If the fiber length is too small it is difficult to produce yarn. Yarn is impossible if the fiber length is less
than 0.5 inch. Thin fibers produce thin yarn and coarse yarn is produced from coarse fibers.

of 38
There are two types of fiber on the basis of length:
 Continuous / filament
 Staple fiber
 Continuous / filament
Long and continuous fibers are called filament. Filaments are continuous in length which can
be used as such form or cut into shorter staple fiber form. These fibers are collected from both
natural and artificial source. Any natural fiber can be made into a filament. When only one
filament is used in a yarn then it is called mono filament. When more than one filament are used
in yarn then it is called multi filament.
Mono filament → 1.5 holes in spinneret.
Multi filament → 10-100 holes.

of 38
 Staple fiber
When the length of fiber is short then it is called staple fiber. Stable fibers are manly shorter in
length and related to natural fiber. All natural fibers without silk can be collected as staple fiber.
Artificial fibers also collected as staple fiber.
Staple fibers are three types on the basis of length:
Short staple: Length is less than 2 inch.
Medium staple: Length is from 2-4 inch.
Long staple: Length is more than 4 inch.
ii. Strength
The capacity of a fiber to support a load is known as fiber strength. The strength is described as
tenacity.
Tenacity = Strength/ linear density.
It is expressed as CN/Tex or N/Tex. The tensile strength is commonly described as the force
required to reach break the increase in the length before breaking is known as extension.
iii. Elasticity
It is the property to recover from deformation. The fiber may be elastic or plastic which depends
upon fiber condition and surrounding environment.
iv. Flexibility
Flexibility is that property to resist repeated bending and folding.

of 38
v. Cohesiveness
It is the ability of the fibers to cling together during spinning depends on crimp and twist. In
natural fiber the property comes from nature but in artificial fiber this property is given by
crimping.
vi. Fineness
The term fineness describes the quality of a fiber. By this, we know how fine a fiber is. It is
expressed by the terms count, tex, denier, tex per unit length etc.
1 Tex = 1 gm/1000m.
1 denier = wt. in gm/900m.
Fineness affects some fiber properties. Such as yarn count, yarn strength, yarn regularity etc.
vii. Cross section
The cross section of a fiber determines the physical properties of fiber. It gives idea about
strength, fineness that varies from fiber to fiber. The cross section shape of a fiber is important
because it contributes to the surface appearance of the fiber. It helps to give properties of luster,
bulk and body of the fibers, yarn and fabrics. It has effect in twisting, bending or shunning.
viii. Crimp
It refers to the waves or bends that take place along the length of a fiber. It increases
cohesiveness and resilience, resistance to abortion and gives increased bulk or warmth to fabrics.
It also helps fabrics to maintain their softness or thickness, increase absorbency and show
contact comforts bid reduces luster. A fiber may have one of the three types of crimp. Namely
– Mechanical crimp, natural crimp or Inherent crimp and Chemical crimp.

of 38
ix. Resiliency
It is the property of a fiber, which enables it to recover from certain load or stretch over a period
of time.
x. Toughness
The ability of a fiber to endure large permanent deformations without rupture is called
toughness.
xi. Work of rupture
The area below the stress –strain curves provides a measure of the work required to break the
fiber. It is called work of rupture and it commonly expressed in CN/Tex.
xii. Appearance
It is expressed by length, fineness, cross-section cleanness and luster of a fabric. Generally short
fibers are bulky and loss lustrous.
xiii. Density
The density indicates the mass per unit volume. The specific gravity of a fiber indicates the
density relative to that of water at 4 degree Celsius.
xiv. Elongation
It is the ability to be stretched, extended or lengthened. Elongation vary at different temperatures
and when wet or dry.

of 38
 Mechanical Properties :
 Tensile Properties.
 Flexural Properties.
 Torsional Properties.
 Fictional Properties
 Electrical Properties
Tensile Properties
Tensile properties indicates how a material will react to the forces being applied in Tension. Fibers
usually experience tensile loads whether they are used for apparel or technical structures. Their form,
which is long and fine, makes them some of the strongest materials available as well as very flexible.
This book provides a concise and authoritative overview of tensile behavior of a wide range of both
natural and synthetic fibres used both in textiles and high performance materials.
Flexural Properties
Flexural properties is one of the mechanical properties of textile material. It is the property or
behavior shown by the fiber or material when we bend it. The importance of Flexural properties is
required when we wear cloth. The flexural test measures the force required to bend a beam under
three point loading conditions. The data is often used to select materials for parts that will support
loads without flexing. Flexural modulus is used as an indication of a material’s stiffness when flexed.

of 38
Torsional Properties
The behaviors which are shown by a textile material when it is subjected to a torsional force is called
torsional property. It is the property of fibre or material when a Torsional force is applied on it. Here
Torsional force is a twisting force that is applied on the two ends of the material in two opposite
direction.
Fictional Properties
Frictional properties is due to the friction between the fibres. This properties are shown during
processing. Too high friction and too low friction is not good for yarn. Therefore it is an important
property when yarn manufacturing and processing.
Electrical Properties
 Electrical conductivity or specific conductance is a measure of a material's ability to conduct
an electric current
 Conductivity is the reciprocal (inverse) of electrical resistivity, ρ (Greek: rho), and has the SI
units of Siemens per meter (S·m-1)
 Resistance –Ohms (e.g. Resistance of Dynamo is > 1014 Ohm)

of 38
Chemical Properties:
Solubility in acquis and organic solvent. Useful properties of another hind desired in a textile fiber are
indicated below.
 Behavior towards dyes.
 Ability to moisture absorption
 Resistance to deteriorating influence including; light, thermal stability, resistance to bacteria,
mildew moth and other destructive insect, corrosive chemicals.
o Water:
Hydrophobic and Hydrophilic are the two classification of fiber according to the interaction of fiber
with water. The fiber which has no joint for water that means less absorbency is called hydrophobic.
o Absorbency:
Absorbency means the ability of the fiber to retain the water which depends on the ratio of fiber’s
amorphous and crystalline region because this ration determines the polarity of the polymers.
o Acid:
Interaction of different fiber with acid variable. To avoid the harmful effect on fiber different acid
should be chosen carefully which will not harm fiber but bring the required change during the
manufacturing process.
o Alkali:
Like acid interaction of fiber varies with the different alkalis. Such as mild alkali don’t have any harmful
effect on wool but high concentration of caustic soda has harmful effect on wool.

of 38
Without above that properties, fiber has also
 Thermal Properties
 Torsional Properties
Electrical properties of Textile Fiber:
The electrical properties (conduction, resistance, etc.) are used in numerous solid materials, which
are for the most part metal or metal derivate. In the textile field these properties are more difficult to
highlight or engineer due to the various other requirements in suppleness, handle and care properties
of such materials.
The electrical properties of fibres are interrelated, for e.g. The liability of materials to develop static
charges is directly related to its electrical resistance, which in turn mainly determined by the
permittivity of the material.
Hence we will concern our discussion to the three major properties i.e.
 Dielectric Properties
 Electrical resistance
 Static Properties.
The permittivity ε of a material may be defined either in terms of capacitance C, of a condenser with
the material between parallel plates of area “A” and separation “d” or in terms of the force “F”
between two charges Q1 and Q2 at a distance “r” in the material. Expressed in SI units, the relation
contains no arbitrary numerical factors and is represented as:

of 38
Here ε0 is the permittivity of a vacuum and has the value of 8.854 X 10-12 farad/metre
For many purposes the term relative permittivity is used which is expressed as:
εr = ε/ ε0, and this quantity is called the dielectric constant.
Dielectric effects are caused due to the polarization in the medium and these results in a reverse field,
which tends to reduce the potential difference between the charged plates of a condenser, which thus
increases the capacitance which is generally calculated as the value of charge/potential difference.
This polarization is due to:
o The alignment of the permanent dipoles such as water molecules.
o Due to the separation of charge forming induced dipoles
C = εA/d -------------------- (1)
F = Q1Q2/4Пεr2 ------------------------- (2)
In vacuum the equation becomes:
C = ε0 A/d -------------------- (3)
F = Q1Q2/4Пε0r2 --------------- (4)

of 38
FACTORS AFFECTING DIELECTRIC PROPERTIES:
Frequency:
The frequency of the applied voltage has an important effect on the dielectric properties. At low
frequencies the dipoles line up in the field, reverse direction when the field reverses and so contribute
to a high permittivity. But owing to their inertia and due to the restraints in the structure, the dipoles
take a certain time to reverse direction, and this is characterized as their relaxation time. With increase
in frequency the field reversals becomes so rapid that the reversals of fields take place at intervals
comparable to the relaxation time, and at that point the dipoles cease to follow the changes in the field
completely and the permittivity will decrease. At further higher frequencies the dipoles will not follow
the changes at all and there will be no contribution to the permittivity. The reversing of the dipoles in the
electric field leads to loss of energy owing to internal friction. At low frequencies the time taken in
reversing is only a small part of the whole cycle, and hence the energy loss and consequently the power
factor are low. At very high frequencies the movement of the dipoles being negligible, the energy loss
and power factor is again low, but near the frequencies corresponding to a relaxation time the dipoles
are moving throughout the cycle and so corresponds to a high energy loss and power factor.
Moisture:
At higher frequencies the dielectric properties of the cellulosic fibres are consistent with the
assumption that the water molecules are restrained in a manner similar to that in ice. For wool the
permittivity is lowerwhich indicates that the absorbed watermolecules are more tightly held and cannot
line up in the field and the behavior is marked at low moisture content and is consistent with the theory
that the water first absorbed by wool is firmly bond to the hydrophilic groups in the side chains of the
keratin molecule

of 38
The permittivity for wool at high frequencies has been explained by Shaw and Windle with a three phase
theory of moisture absorption. The components of the system were regarded as dry wool, with
experimentally determined properties, localized absorbed water in which the molecules cannot rotate,
intermediate absorbed water in which the molecules are very little restricted and mobile absorbed
water in which the molecules are as free as in liquid water.
The non-absorbing fibres like Saran and Dacron show no variation in dielectric constant and only a
small change in power factor between 0 and 65% RH.
The effect of temperature: Arise in temperature reduces the restraints on the dipoles causing an
increase in the permittivity in solid materials. In case of liquids and gases where the intermolecular
restraints are small an increase in temperature causes a greater disorganization, a less regular
alignment of the dipoles and thus a lower permittivity.
Direction of applied current: In case of an anisotropic material such as fiber the permittivity varies
with the direction in which the electric field is applied. For cotton fiber it was seen that the axial
permittivity is about twice the transverse permittivity, while Shaw and Windle found that the relative
permittivity of dry wool fibres was 3.88 +(-) 0.15 with the electric field parallel to the fiber axis and
4.41+(-) 0.11 with the electric field perpendicular to the fiber axis.

of 38
Presence of Impurities:
The presence of impurities have a considerable effect on the permittivity of the fibres, ionic impurities
in particular would have considerable effect at low frequencies.

of 38
ELECTRICAL CONDUCTIVITY AND RESISTIVITY
Electrical conductivity is the capacity of a material to allow the passage of an electrical current.
Resistivity is the inverse of conductivity. One must distinguish the resistance (R) which characterizes a
physical element and the resistivity which defines the intrinsic nature of the material constituting the
element as two objects may be constituted of materials with different resistivity but share the same
electrical resistance value in ohms.
Ohm’s law defines the resistance (R) as the relation of the potential difference (V) applied to this
element on the current (I) traversing it:
R = V/I ----------------------------- (5)
There are three types of resistivity according to whether the material is presented in a linear, surface
or volume format.
 The linear resistivity Rl of a uniform linear element is characterized by the measure of
the resistance compared to its length and is expressed in ohm/centimeter (O/cm):
Rl = R/L ------------------------------ (6)
With R = resistance in ohms, L = the length of the sample.

of 38
 The surface resistivity Rs characterizes flat materials of little thickness such as fabrics,
and it is expressed in ohm (O) or in ohm/Sq(O/¨Sq)
Rs = R x L/D ------------------------- (7)
With R = the resistance in ohms, L = the length of the electrode, D = the distance between the
electrodes.
 The volume resistivity Rv characterizes the three dimensional materials by the measure
of the resistance R compared to the surface S, and to the length L. It is expressed in
ohm. centimeter (O.cm):
Rv = R x S/L --------------------------- (8)
Here, R = resistance in ohms, S = the surface area of the electrodes, L = the length of the sample.
FACTORS AFFECTING FIBRE RESISTANCE:
Moisture:
It is the most important factor which determines the resistance of textile materials and causes a
variation over a range of at least 1010 times the difference in 10 and 90 % r.h. causes a million fold
difference of resistance.
For most hygroscopic materials textile fibres between 30 and 90% r.h, relations of the following form
hold:
Log Rs = -n Log M +Log K -------------------- - - (9)
Rs. Mn = K,
Here M = moisture content (%), and n and K are constants
At low moisture contents the following form fits:
Log Rs = -n’ Log M +Log K’ ---------------------- (10)
Here n’ and K’ are constants

of 38
At a constant temperature the resistance has been found to be a single valued function of moisture
content, with no hysteresis being detected.
Effect of Impurities:
The resistance of the hygroscopic fibres depend on their electrolyte content. The addition of a salt
such as potassium chloride lowers the resistance. At low salt contents, the evidence indicates that the
conductivity is approximately proportional to the electrolyte content, but, at high salt contents the
resistance of the cellulose film at given moisture content was independent of the nature or amount of
salt present.
Washing in distilled water increases the resistance and washing in calcium sulphate increases the
resistance even further.
The calcium sulphate solution replaces the monovalent ions left behind after washing in distilled water
and replaces it with less conducting bivalent ions. The residual ions associate with the remaining groups
in the fiber molecule for example carboxyl groups present as impurities in cellulose molecules. It was
found by church that when hydrogen ions were replaced by calcium ions in paper the resistance
increased by six times.
Effect of Temperature:
The resistance of fibres decreases as the temperature increases, a rise of 10°C causes a fall of the
order of five times.
For cotton, viscose rayon, and wool, Hearle found that the rate of change of log R with temperature
varied separately with moisture content, M and temperature Ө°C
Log R = (Log R) Ө°C, M=0 - (a-bM) Ө + C/2 Ө2
Here a, b, c are constant for a given material.

of 38
The value of ‘a’ gives the rate of change of log R with temperature under dry conditions at 0°C and the
value of ‘b’ and ‘c’ give the change of d(log R)/d Ө, with moisture content and temperature respectively.
Polarization and Related Effects:
If polarization occurs by electrolytic or due to electrostatic charges occur, it will cause back e.m.f.s
which is detectable in three ways:
The resistance ill increase with time as the back e.m.f develops.
The resistance will decrease with voltage
The back emf will be present and will die away as the applied voltage has been applied.
It was found by several researchers that there is a negligible variation of resistance with time, except
at low and high humidity.
The first understanding of the nature of electricity came from the study of the phenomenon of static
electricity in the eighteenth century. Later the increased amount of trouble caused in the textile industry
due to the introduction of the new fibres renewed and revived interest in understanding of this
phenomenon.
Similar charges repelone another. This causes difficulty in handling materials, the filaments in a charged
warp will bow out away from one another, there will be ballooning of a bundle of slivers, cloth will not
fold down neatly after coming out of a folding machine. Similarly, unlike charges attract one another.

of 38
This phenomenon has caused difficulty in opening of parachutes. It will also cause two garments which
are oppositely charged to stick to one another causing embarrassment to the wearer. Another
consequence is the attraction to a chargedmaterial ofoppositely charged particles of dirt and dust from
the atmosphere. When the fabric is positively charged the soiling is worse owing to the preponderance
of negatively charged dirt particles in the atmosphere. This fine dirt adheres so firmly that it is difficult
to remove and causes serious soiling. This is the reason for fog marking which occurs on the portion of
the cloth in a loom that is left exposed overnight.
Formation of static: Most textile fibres do not conduct electricity efficiently and can be classified as
dielectric material, demonstrating insulating properties when dry. Whenever two surfaces come into
contact, electrons can flow from one to the other. Conducting materials allow this electron flow to be
equalized instantly when the surfaces are separated. Insulating materials like textile fibres can retain
the electrical charge difference for some time. It was initially opined that the two necessary conditions
for a charge to appear are:
 Difference between the nature of the surfaces
 Rubbing between them
Pioneering work by different researchers has established that either of these conditions in itself is
sufficient to generate charges. Rubbing though not necessary increases the amount of charge produced
significantly. Triboelectrification is the term used for electrical charges generated by frictional forces.
Fibres can be ordered in a triboelectric series such that each fiber type becomes positively charged
when rubbed with fibres below it in the series and vice-versa

of 38
Owing to the slight differences in the surface or the asymmetry in the rubbing, charges may easily be
generated by inter-fiber contact between apparently identical fibres.
FACTORS AFFECTING STATIC GENERATION:
Conductivity: The increase in conductivity or the lowering of resistivity reduces the static charges
generated in the fiber. The resistivity as discussed earlier is the resistance of the fiber to electrical flow.
Increasing the conductivity produces a lower charge build up and a more rapid dissipation.
Frictional forces: Lowering of the frictional forces between the fibres by enhancing its lubricity helps to
reduce static generation by decreasing the initial charge build up.
Moisture:As discussedearlier thepresence ofmoisture in thefiberincreases theconductivity andhence
the dissipation of charges from the fiber is faster, resulting in lowering of the static charges.

of 38
Measuring the contact resistance between the
electrode and the textile substrate:
The surface resistance of flat textile products is substitute resistance resulting from the yarns
resistance and contact resistance occurring between the yarns forming a fibrous structure. Due to the
new useofelectricallyconductive textiles,e.g.electrodes to muscle electricalstimulation, it is important
to uniform distribution of the resistance measured between any points on the surface of the sample. The
authors have proposed a new approach for measuring the resistance of the flat textile of electro
conductive properties. The measurement method is based on multi-variant testing of the electro
conductive properties using four cylindrical electrodes placed on the sample surface. At some scale the
electrode contact area is never completely flat. There are non-conducting and conducting regions
between contact area of an electrode and a sample. This is due to the porous structure of textile
materials and pressure force of the electrode. The measuring electrodes were made of brass and silver
plated. The electrode contact diameter is 8 mm. The mass of a single electrode is 24 g, which means that
its pressure force equals to 0.24 N. The electrodes have a comparatively small contact area with the
textile substrate relative to the sample surface. The contact area of the electrode was selected so that
it covers the fabric repeat. It is very important to ensure that the all yarns are contacted during
measurements.
In order to determine the contact resistance between the electrode and the textile sample measuring
stand was built. The scheme of the stand is shown in Fig.

of 38
Measurement system for determination of a contact resistance
The contact resistance measurementwas conducted using the indirect method. DC Power Supply Agilent
E3644A meter as voltage source was used. The current I was forced between the upper end of the
electrode and a point on the thin copper measurement probe introduced into the electrically conductive
sample. The probe was located in the immediate vicinity of the electrode and does not touch with the
electrode. Using an Agilent 34410A ammeter the current value was recorded. Using an Agilent 34410A
voltmeter voltage drop between the upper end of the electrode and a point on the wire was measured.
Equivalent resistance scheme of measuring system is shown in Fig.

of 38
Equivalent resistance scheme: I—the current; U—the voltage source; U c —the voltage; Re—the
electrode resistance with the connecting wire; Ue—the voltage drop in the electrode; Rc—the contact
resistance
The equation resulting from the above connections (Fig. ) is given by the following formula:
U−ReI−RcI=0U−ReI−RcI=0 (1)
Here: U—the voltage source; I—the current; R e —the electrode resistance with the connecting
wire; R c —the contact resistance.
The contact resistance is given by the formula:
Rc=UcIRc=UcI (2)
Here: U c —the voltage source; I—the current.
The measurements of the contact resistance were repeated five times. The average contact resistance
value calculated from the formula (2) is equal to 0.049 Ω. Because the value is small so it is expected
that the power loss under the electrode will be small. Therefore the contact resistance has no significant
impact on surface resistance of the textile sample.

of 38
Measurements of surface resistance of textile
sample
The purpose of the study was to determine the resistance R of the textile sample and comparison of the
received measurements results. The qualitative model of the research object, the woven fabric sample,
is shown in Fig. 4.
Fig. 4
The qualitative model of the research object
The measurement model was defined as follows:
R=f(I,Um)=UmIR=f(I,Um)=UmI (3)

of 38
Here: I—the current flowing between one pair of electrodes; U m —the voltage drop measured between
the other pair of electrodes.
It is assumed the estimates of quantities I and U m are uncorrelated.
The measuring stand designed for conducting multi-variant study of the electro conductive properties
of textile sample was built (Fig. 5). The measuring stand consists of the following elements:
Fig. 5
The measuring stand for multi-variant textile resistance measurements
Full size image
An Agilent 34410A multi-meter;
a DC Power Supply Agilent E3644A meter;
a table (A) (Fig. 5) or, alternatively, table (B) (Fig. 6);

of 38
Fig. 6
Table (B) for the square-shape arrangement of electrodes on a sample—top view
Full size image
sets consisting of four cylindrical measuring electrodes.
Table (A) enables the resistance measurement bythe four electrode method (Fig. 5).An identicalspacing
between electrode mounting holes are assumed. The distance between the two outermost holes
corresponds to the longest square side that can be achieved when arranging the electrodes using table
(B) (Fig. 6). This table allows electrodes to be arranged in the shape of a square with a side of 70, 50
and 30 mm, respectively. The drilled holes allows the electrode to fall freely under its weight onto the
fibrous substrate, while retaining the perpendicular direction of the electrode relative to the substrate.
In the case of table (A) the two outermost electrodes are connected to a current source (the DC Power
Supply Agilent E3644A meter). To measure the voltage drop, the two inner electrodes are connected to
the Agilent 34410A mustimeters. In the case of using table (B), two adjacent electrodes are connected
to a current source (the DC Power Supply Agilent E3644A meter). To measure the voltage drop, the two
remaining electrodes are connected to the Agilent 34410A mustimeters. For determining the resistance
of the woven fabric sample 10 variants of electrode arrangement on the sample surface were selected
which were denoted as A1, A2, B1, B2, C1, C2, D1, D2, E1, E2. The manner of electrode arrangement together
with electrical circuit of the resistance measurement are shown in Figs. 7 and 8.

of 38
Fig. 7
Arrangement of electrodes in the four corners of the electro conductive sample (variants: A and B)

of 38
Fig. 8
Coaxial arrangement of electrodes on the surface of the electro conductive sample (variants: C, D and
E)
For the coaxial electrode arrangement, table (A) was used. For arranging the electrodes in the corners,
on the other hand, table (B) was used.

of 38
Conclusion:
From the above discussion it is clear that the electrical properties of fiber is dependent on the moisture
content, relative humidity, frequency of the applied voltage and the intrinsic properties of the material
itself.
A variety of mechanism can cause a transfer of charge to occur at the surfaces in contact. Large
charges develop at thesurface ofcontactbut these leaks awaythrough theair, ormaterial and observed
charges are much lower.
The limiting condition forhighstatic charges,and hence thesusceptibility to troubles in use, is dependent
on the resistance of the material. Low resistance materials like cotton, viscose rarely give any static
problem while high resistance material like wool and silk and synthetic fiber will cause a tremendous
amount of static generation.

of 38
Reference:
1. https://textilelearner.blogspot.com/2012/02/what-is-textile-fiber-types-of-textile.html
2. https://www.academia.edu/19491963/Electrical_and_Electronic_Properties_of_Fibers?auto=download
3. https://textilelearner.blogspot.com/2011/07/textile-fiber-properties-of-textile.html
4. https://textilemerchandising.com/properties-of-textile-fibers/
5. https://textilelearner.blogspot.com/2013/properties-of-fiber-properties-of.html
6. https://www.technicaltextile.net/articles/electrical-properties-of-fibres-6699
7. M. Pacelli, G. Loriga, N. Taccini, R. Paradiso, in IEEE/EMBS International Summer School on Proceedings of
International Summer School and Symposium on Medical Devices and Biosensors (ISSS-MBDS 2006), Boston,
USA, 4–6 September 2006, pp. 1–4
8. V.K. Mukhopadhyay, J. Midha, J. Ind. Text. 37, 225 (2008)
9. S.L.P. Tang, Trans. Inst. Meas. Control 29, 283 (2007)
10. B. Karaguzel, C.R. Merritt, T. Kang, J.M. Wilson, H.T. Nagle, E. Grant, B. Pourdeyhimi, J. Text. Inst. 100, 1 (2009)

of 38
THANK you SirTHANK you SirTHANK you Sir
THANK you Sir

Electrical properties of textile fiber

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Similar to Electrical properties of textile fiber

Similar to Electrical properties of textile fiber (20)

Recently uploaded

Recently uploaded (20)

Electrical properties of textile fiber