1. Various Methods for Analysis
of
Textiles-fibre Content, Yarn
and Fabric Structure
Presented By:
Mona Verma
Ph.d. Research Scholar
Deptt. of Textile and Apparel
Designing, CCSHAU,HISAR
mona.verma35057@gmail.com
2. Importance of analysis of fibre content ,yarn and fabric
content:
Fibre identification is an important first step in predicting the
behavior of a textile artifact in various environments.
Knowing the identity of the fibre is also helpful in planning
appropriate conservation treatment or storage methods.
The procedure of identification of the fibre content of a fabric
depends on the nature of the sample, the experience of the analyst,
and the facilities available. Because laws require the fibre content
information presented with the displayed material in the museum or
in the labeling done on the articals.
3. Several factors can complicate the identification of
fibres within a textile artifact:
The poor condition of a degraded historic textile may make it difficult
or even impossible to identify the characteristic diagnostic features of
fibres.
Yarns that are blends of two or more fibre types, including man-made
fibres, can complicate the interpretation of the results of burn tests.
Consequently, another test method such as microscopic examination
of fibres should be used to confirm the results of the burn test.
Neither a burn test nor a microscopic identification is regarded as
conclusive on its own, but either can be used as a confirmatory test.
4. Methods of Fibre Content Analysis:
Visual inspection method: by using appearance and feel
Burning test method
Solubility test method
Microscopic method
6. Visual inspection method
Visual inspection of fabric for appearance and hand is always the first step
in the fibre identification.
It is no longer the possible to make an identification of the fibre content by
the appearance and hand alone because other other man made fibres also
show the same feel and tough. So other test also used along with visual
inspection test to confirm the identity of the fibres.
This test only suits to the experienced analyst . But some times absence of
the other resources.
We use this method. However observation of the following characteristics is
helpful.
Length of the fibre: untwist the yarn to determine length. any fibre can be
made in staple length ,but not all fibres can be filament. for example, cotton
and wool are always staple.
Luster and lack of luster
Body , texture, hand-soft to hand ,rough to smooth, warm to cool or stiff to
flexible.
10. Fibres When Approaching
Flame
When In Flame After Removal
From Flame
Ash Odor
Cellulose
Cotton
Flax
Does not fuse or shrink
from flame
Burns Continues to
burn, afterglow
Gray feathery,
smooth edge
Burning paper
Protein
Silk
Wool
Curls away from flame Burns slowly Usually self
extinguishing
Crushable black ash Burning hair
Acetate Fuses away from flame Burns with
melting
Continues to burn
and melt
Brittle black
Hard bead
Acrid
Acrylic Fuses away from flame Burns with
melting
Continues to burn
and melt
Brittle black
Hard bead
-
Glass Does not burn
Modacrylic Fuses away from flame Burns very slowly
with melting
Self extinguishing
,white smoke
Brittle black
Hard bead
-
Nylon Fuses and shrinks away
from flame
Burns slowly with
melting
Usually self
extinguishing
Hard gray or tan
bead
Celery-like
Olefin Fuses and shrinks away
from flame
Burns with
melting
Usually self
extinguishing
Hard tan bead -
Polyester Fuses and shrinks away
from flame
Burns slowly with
melting; black
smoke
Usually self
extinguishing
Hard black bead Sweetish odor
Saran Fuses and shrinks away
from flame
Fuses and shrinks
away from flame
self extinguishing Hard black bead -
Spandex Fuses but does not
shrink from flame
Fuses but does not
shrink from flame
Continues to burn
and melting
Soft black ash -
14. Fiber Heat Age Sunlight Acids Alkalis Insects Micro
Organis
ms
Electrical
conductiv
ity
Cotton No effect upto
1200C. Starts
decomposing at
1500C
Little effect if
stored
properly
Gradual loss
of strength
turns yellow
Attacked by
hot, diluter or
cold conc.
Acids
Resistant.
Swells in
caustic soda
but not
damaged
Not
attacked by
moths or
beetles
Attacked
by fungi
and
bacteria
when damp
Good
insulator
when dry
Wool Becomes weak an
looses softness
decomposes at
1300C
Little
deterioration
if stored
carefully
Decompositi
on with loss
of strength
Attacked by
sulphuric acid.
Decomposes
completely
generally
resistant to
other mineral
acids
Dissolves in
caustic soda.
Soda and
soap have to
be used with
care
Attacked
by moths
and other
insects
Good
resistance
to mildew
and other
insects
Good
conductor of
heat and
electricity
Silk Unaffected upto
1400C.
Decomposes at
1750C
Suffers
gradual loss
of strength
Encourages
decompositio
n
Decomposed by
strong acids.
Mild acids have
not effect
Less readily
damaged
than wool
dissolves in
con caustic
alkali
May be
attacked by
moths
Not usually
attacked by
mildew
Poor
conductor of
electricity,
used for
insulation
Viscose Begins loosing
strength at 1500C.
Decomposes
above 1850C
Practically no
effect
Good
resistance
prolonged
exposure
causes
gradual loss
of strength
Attacked by
hot, dilute or
cold conc.
mineral acids
Resistant to
dilute alkalis
but strong
ones cause
swelling
with
strength loss
Resistant to
insects,
however
attacked by
silver fish
Not readily
attacked by
mildew.
Sever
attack
weaken
fibers
Poor
insulator
15. Fiber Heat Age Sunlight Acids Alkalis Insects Micro
Organisms
Electrical
conductiv
ity
Acetate Practically
unaffected upto
1200C Melts at
2320C
Slight fall
in strength
over
prolonged
exposure
Slight
deterioratio
n after
prolonged
exposure
Not affected
by weak
acids
Conc.
solutions of
strong acids
decomposes
the fiber
Dilute
alkalis
have no
effect.
Strong
ones
cause
saponifica
tion
Normally
not
attacked
by moths
and other
insects
High
resistance
bacteria may
cause
damage and
discoloration
Good
insulator
Triacetate
(Tricel)
Softens at 2250C
melts at 3000C
Highly
resistant
Highly
resistant
Good
resistance
Grater
resistance
to
saponifica
tion than
acetate
Not
attacked
by moths
and other
insects
Highly
resistant to
micro
organisms
Highly
electrical
resistance
Polymide
(Nylon)
Unaffected upto
1500C Melts at
2500C
Effect
negligible
Gradual
loss of
strength on
prolonged
exposure
Hot mineral
acids
decompose
nylon
Not
affected
by alkalis
Not
attacked
Not attacked Very good
insulator
16. Fiber Heat Age Sunlight Acids Alkalis Insects Micro
Organisms
Electrical
conductivi
ty
Polyester Excellent
resistance to
heat. Melts at
2600C
Practically
no effect
Good
resistance
Gradual
loss of
strength
after
prolonged
exposure
Not affected
by weak and
moderately
strong acids.
Conc.
sulphuric
acid
decomposes
the fiber
Good
resistance
to weak
alkalis,
but
decompos
ed by
strong, hot
alkalis
Not
attacked
Not attacked Excellent
insulator
Acrylic Excellent
resistance to
heat, starts
sticking at
2550C
Negligible
effect
Excellent
resistance
to sunlight
Good
resistance to
mineral
acids
Good
resistance
to weak
alkalis,
but
degraded
by hot
conc.
alkalis
Not
attacked
Not attacked Excellent
insulator
Poly-
propylene
Resistance good
upto 1100C.
Softens at 1600-
1700C
Little effect Stabilized
fiber has
excellent
resistance
Excellent
resistance
but affected
slowly by
conc.
sulphuric
and strong
nitric acids
Excellent
resistance
to conc.
hot alkalis
Complete
ly
resistant
Not attacked Excellent
insulator
23. Direction of Twist
Twist is defined as the spiral arrangement of the fibres around the axis
of the fibre. the direction of twist is described as s twist and z twist.
A yarn has s twist ,if when held in vertical position, the spirals
conform to the direction of slope of the central portion of the letter
“s”.
It is called z-twist if the direction of the spirals conforms to the slope
of the central portion of the letter “z”. Z twist is standard twist used
for weaving yarns.
24. Yarns are twisted either to the right (Z-twist) at to the left (S-
twist).the amount of twist is measured by the number of twist per
inch( t.p.i.).
Low twist -0-3 tpi
Medium twist -3-7 tpi
High twist-7-12 tpi
Twist count
The amount of twist depends on the size of the yarn, the use to
which it will be put and the length of fibres from which it is made.
Fine yarns requires more twist than coarse yarns.
25. The amount of twist in a yarn determines many of the characteristics.
As yarn is twisted, it shortens and takes on potential strength .
High twist in crepes and georgettes produces much shortening of the
yarn and gives possibilities of much stretchiness.
High twist also reduce luster.
27. Types of fabric: based on the method of construction
the fabric is divided into various categories.
Woven fabric: a woven fabric consists of two sets of yarns which
are interlaced at right angles to each other to produce a compact
construction.
Knitted fabric: in the knitted fabric the yarn is interloped.
Only one thread is used in the knitting process. Wales and
Courses are formed.
Nets : these nets are usually of nylon and are open mesh fabrics
with large geometrics interstices between the yarns.
Laces: it is an openwork fabric consisting of a network of
theads or yarns formed into intricate design.
28. Braided fabric: these have a diagonal effect ,made by plaiting 3 or more
yarns that originate from a single location and lie parallel before the
interlacing occurs.
29. Bonded fabrics : these have layered fabric structure in which a face or
surface fabric is joined to a combined fabrics use as a shacking fabric.
Film fabrics : these drive from some chemicals as some of the manmade
fibers , extruded in sheets instead of filaments.
30. Laminated fabrics: these have a layer of fabric joined to a sheet of
material, frequently polyethylene foam adds warmth and stability.
31. Tufted fabrics: tufting is a process of manufacturing pile fabrics by inserting
loops into an already woven ground fabric.
Non woven fabrics: these are the material made of textile fibers held together
by an applied bonding or adhesive agents or by the fussing of self contained
thermoplastic fibers. Nonwoven fabrics are broadly defined as sheet or web
structures bonded together by entangling fiber or filaments (and by
perforating films) mechanically, thermally or chemically.
33. This is a simplest form of weaving.
The weft yarn passes over one warp yarn and
under the next alternately across the entire
width of the fabric.
Plain weave has no wrong side unless
coloured finish is applied to differentiate right
or wrong side.
Attractive fabrics can be obtained by varying
the number of warp yarns and filling yarns.
Most fabrics are made using plain weave. It
produces strong and durable fabrics.
Plain weave:
34. Twill weave
The second basic weave pattern is the twill
weave. A twill weave always shows diagonal
ridges across the fabric.
The twill or diagonal weave may run from
left to right, or from right to left, both on the
face and back of the cloth.
The simplest twill weave uses three warp
yarns and three weft.
Twill weave has increased strength and
warmth but more easily torn by abrasion.
Examples are denim, drill, jean, some
flannel and suitings.
35. Twill-weaves are also classified based on
the yarns that form floats and wales on the
right side of the fabric.
If warp floats are present or prominently
seen, it is called warp-face twill-weave .
Warp-faced twill-weaves are stronger
because of the higher strength and increased
resistance to abrasion of warp.
Warp or weft-faced twill weave
36. Sateen weave
This weave makes use of low-twist floating warp yarns of
lustrous man-made or silk filaments.
The warp yarns pass over a number of weft yarns and under
one alternately, so that the warp floats are on the surface
along the length of the fabric.
The weft yarns are hardly noticeable. A variation of the satin
weave in which the filling yarns float on the surface of the
fabric is satin weave. Example damask, sateen,ticking and
Venetian
37. The smooth shiny surface of a satin weave is
created by the large surface area of exposed warp
threads which are intermittently bound on only
every fourth cross of the weft (four under, one
over).
This sequence can be reversed so that the weft
threads form the dominant surface area of the
fabric (four over, one under) though this type of
weave is called “sateen”.
Satin weaves are frequently used in combination
with other weaves to form “figured” cloths.
Figured cloths are woven in one colour with
pattern created solely by the use of different
textured weaves, for example damask.
38. The weave uses doubled warp and weft
yarns to produce design that resembles
familiar pattern of a basket.
Two or more weft yarns pass alternately
over and under two or more warp yarns.
In this, two or more filling yarns with little or no twist are interlaced
with a corresponding number of warp yarns; they are woven in a
pattern of 2 ×2, 3 × 3 or 4 × 4 instead of 1 × 1, which is the plain
weave.
In this construction the fabrics are not durable, but are more
decorative. Examples are coat and suit fabrics, hopsock.
Basket weave
39. Ribbed-weave fabric is an unbalanced weave.
Raised effect is produced along the warp or
weft direction by using thicker warp or weft
yarns or by allowing warp or weft to pass over a
set of weft or warp yarns while interlacing.
Warp-faced rib fabrics are usually termed
corded weaves.
The rib appearance is made by using heavy
yarns in the warp or filling direction, by
grouping yarns in specific areas, or by having
more number of yarns in warp than filling.
Examples are poplin, broadcloth and
grosgrain.
Ribbed weave
40. Ottoman
An ottoman structure has to have a
horizontal ribbed weave, a filler yarn is used
to produce the raised cording effect. The
structure comprises of two warps and a thick
filler yarn for the cording. The second warp
catches the corded rib here shown by the use
of the black thread.
Corduroy
A strong and hardwearing cut pile cotton cloth
identifiable by its characteristically ribbed
surface, the ribs may vary in width. Woven in a
similar manner to velvet with the pile formed
by the weft threads.
41. Dobby Weave
Dobby designs have small figures such as dots, geometric
designs and floral patterns woven into the fabric.
The design is produced by a combination of two or more
basic weaves and the loom may have upto thirty two
harnesses.
Examples of dobby weave are shirting madras, pique, huck
towelling.
Novelty Weaves
Novelty Weaves are also called as decorative, fancy, figure and design weaves.
They are formed by predetermined changes in the interlacing of warp and filling
yarns. The different weaves include:
Dobby
Jacquard
Leno
pile
and double cloth.
42. This weave is also known as gauze or doup weave. Leno
weave produces open-textured fabric that may be sheer or
heavy.
In this weave the ‘doup’ facilitates twisting one warp
against the neighboring warp before the shed is formed, so
that filling is held between such intertwined warps.
This unusual twisting of the warps like the figure of ‘8’
holds each filling firmly in place, thereby preventing any
possible weft slippage.
This increases weave’s stability, strength and durability of
the sheer fabrics, which are also crisp in texture.
Leno weave
43. Jacquard weave is the one characterized by
large designs woven in intricate details.
The Major advantage of the jacquard
machine is its ability to control each
individual warp thread instead of threads as
in harness looms.
The control over individual warp offers
greater freedom for the designer in evolving
large and intricate woven motifs on fabrics.
Jacquard weave
44. This cloth comprises of two fabrics, each with
its own warp and weft, these warps can be
combined together, but are more usually crossed
over to produce a pattern.
The primary object is to produce a heavier
cloth than could be done in a single texture,
without spoiling the fineness and the weave of the
face cloth.
Double cloths are reversible with the different
colours alternating from the front to the back.
They can also be referred to as compound cloths.
Double cloth
45. Extra warp or filling yarns can be interlaced on the basic
weaves to produce different designs.
These include:
Lappet weave
Swivel weave
Pile weave
Spot weave
Double weave
Surface Figure Weaves
46. This weave is used to superimpose a small design on
the face of the fabric as it is being woven.
Though it is referred to as a weave, the design is
stitched into the fabric by needles that operate at right
angles to construction. Thus the effect produced is very
similar to embroidery.
The design is made with one continuous additional
yarn carried on the back of the fabric from one design to
the next.
The floating threads in between the designs are cut if
they are long; otherwise they are left uncut, which at
times may result in snagging.
Lappet weave
47. This weave is made with extra-filling threads.
This is at times referred to as tabby, home-spun or taffeta-weave.
It is the simplest to produce and consequently inexpensive; this is a
weave in which each warp goes over one weft, and on return it alternates
pattern of interlacing.
Therefore it is called 1/1 weave; numerator indicates number of
harnesses raised and denominator of lowered while shedding.
Swivel weave
Separate shuttles are placed at each point where the
design has to be made.
The shed is formed by the pattern, where the shuttle
carries the yarn through the shed, the distance of the
pattern.
The extra filling floats on the back of the fabric, the
long floats is cut away after weaving is completed.
Example : silk sarees.
48. Spot designs are formed by extra warp or filling yarns.
The yarns are inserted the entire length or width of the
fabric, spots or dot designs are formed.
The long floats on the back side are cut away, leaving
the dots.
The threads can be pulled easily. Filling threads are
easy to cut but warp floats are difficult.
Example : dotted swiss.
Spot Weave
49. Pile fabrics are formed by having the basic plain or
twill weave as a backing and a third yarn is woven to
yield a surface pile.
The pile may be warp pile or weft pile. For making
ground fabric, plain or twill weave is used, the extra set
of filling yarn floats over three or more warp yarns.
The floats are cut and brushed up to form pile. This is
called filling pile.
Examples are velveteen and corduroy fabrics.
If an extra warp yarn floats over the filling yarn, it is
called warp
pile. Examples are velvet, velour and rug velvet.
Pile weave
50. Double weave fabrics are obtained by using five or more set of yarns.
The most common types of double cloth have two set of warp and
two set of weft yarns with an extra yarn interlacing both the cloth.
The double cloth has additional bulk, strength and warmth. Examples
are coatings, blankets, double brocade.
Double weave
52. The fabric count is the number of warp yarns (ends) and filling
yarns (picks) per inch in a woven fabric.
Pick glass with pointer was used to determine fabric count using
standard test method.
It was determined by counting the number of threads per square
inch in the warp and weft directions at five different places in the
fabric. An average of five readings was taken.
Fabric Count
53. The weight of fabric is defined as weight of a known area of the
material and then computing the weight per unit area.
Samples were cut at random from fabric with the help of round
cutter for GSM. The samples were weighed separately on the
Paramount Precision Scale for GSM (grams per square meter)
using standard test method.
Fabric Weight (weight per unit area)
54. Fabric thickness is defined as the distance between two parallel
surfaces while exerting a specified pressure on the material.
Thickness tester was used to determine the thickness of fabrics.
A specimen was placed on flat surface below pressure foot of the
instrument without any folds and wrinkles.
The pressure foot was lowered upon the specimen gently until
the pointer of the dial meter stopped moving further and the
reading on the dial gauge was recorded in mm.
Fabric Thickness
55. Tensile strength is the ability of the fabric to withstand the load of
force usually expresses as kilogram and percent elongation of fabric
corresponding to the tensile strength is the original length of the
sample at breaking point.
The sample of size 6×4 ± 0.05 inches were cut out from warp and weft
direction of the fabric with the help of template. The samples were
mounted between the jaws with approximately 1.5 inch of fabric
protruding from each side of the jaws at a distance of 3 inches .The
speed of upper jaw was adjusted at 300±10mm/min. The machine
was started and the upper jaw moved in upward direction. The
readings were taken from the digital display at sample break.
Tensile Strength
56. Bending length is the length of fabric that will bend under its own weight
to a definite extent. The bending length of the samples were determined
by the paramount stiffness tester.
Samples of size 25×200 mm were cut from warp and weft direction with
the aid of template and conditioned.
Both template and samples were transferred to the platform with the
fabric underneath, coinciding the zero mark of the scale and zero line
engraved on the side of the plate form. The template was moved slowly
over the 41.50 slope along with the strip till the top of the specimen
viewed in the mirror cut in between both index lines. The bending length
was read from the scale, which coincided with the front edge of the top
plate.
Bending Length
57. Pills are the balls or bunches of tangled fibres that are held on to the surface of a
fabric by one or more fibres. Pilling resistance is the resistance to form pills on a
textile fabric.
This method covers the determination of resistance to the formation of pills and
other related surface changes on textile fabrics.
The fabric sample measuring 5X5sq inch was sewn so as to fit firmly when
placed around a rubber tube of 5 inch length, 1 ¼ inch outside and 1/8 inch thick,
which was then rotated for 5 hours to complete 18,000 revolutions at the rate of 60
revolutions/min.
After tumbling, the extent of pilling was assessed visually by comparing with the
arbitrary standards – 1,2,3,4 and 5.
Rating Scale
1 – No pilling
2 – Slight pilling
3 – Moderate pilling
4 – severe pilling
5 – Very sever pilling
Pilling Test
58. Design is classified into two types:
Structural Designs
Decorative Designs
Structural design is a form of construction that is built into the cloth during the
process of its manufacturing. Simplicity is a feature of structural design because
the design is an integral part of its form rather than an embellishment. In textile
design weaving is the most common method of producing structural
design. Non-woven methods like knitting, lace making can also be included in
this category.
Decorative design is applied to the surface of the cloth to ornament it. The
common method of producing decorative design in the field of textiles includes
printing, dyeing, embroidery, appliqué and painting in addition to trimmings
and certain finishing methods.
Identification of Design on Fabric
59. Naturalistic designs/ conversational
This depicts real objects in a natural manner. Flowers, animals, plant forms,
human figure of any other object may be selected for representation certain
traditional patterns. They also called novelty patterns. Examples are Animals,
animal skins, cartoons, fruit, games, toys, mythological designs, vegetables,
shells, sports and jungle etc.
60. Stylized designs/ Floral designs
These distort real objects. In this natural designs are simplified, exaggerated,
rearranged or even distorted to achieve the purpose of the design. In textile
industry, patterns of richly coloured, delicately petaled roses and patterns of
rose’s sharp thorns are both referred to as floral.
The floral category includes all the gatherings of the flower garden, in fact
including grasses, but agricultural produce like fruit and vegetables is
considered a conversational subject. Floral motifs are more common in
women’s clothes and furnishing materials. Examples of floral patterns are
ambi motif ,peacock motif.
61. Geometric Designs
geometric is to use the vocabulary of the textile industry, but it also makes
them round rather like the subject of a mathematics Class.
These are based on pure forms of the circle, rectangle and triangles etc.
Geometric motifs include stripes, dots, checks, and plaids as well as many less
usual forms.
A geometric is an abstract or non-representational motif, a shape that is not a
picture of something out in the real world. Examples of geometric designs are
basket weave design, check board, chevron and herringbone weave, diagonal
stripes, diaper pattern, ogee pattern, plaids and polka dots.
62. Abstract Designs
These have little or no reference to real object. Abstract implies
an element of impression and a greater freedom than is found in
most geometric designs. This type of design is used in modern art.
64. STRAIGHT/
block
REPEAT
A straight repeat can
be produced by
repeating your motif
at measured
intervals, placing
each motif directly
under or alongside
the previous one.
65. BRICK
REPEAT
A brick repeat is
produced by
repeating the
motif at the
sides as before,
but moving the
second row
sideways as
shown, like the
pattern formed
in for example a
brick wall.
