2. 2
You can not assume that to dye any
piece of fabric to a given colour, all you
need to do is use a dye of that
particular colour.
No dye will dye all textile fabrics
satisfactorily.
This means, simply, that you must
choose a dye that will suit the material
(or a material that will suit the dye).
3. 3
Classification of Dyes
• No single class of dye can dye all fibres.
• A specific class of dye can only be applied
to a given type of textile fibre.
5. 5
C lassification of dyes
M a in
D ye G e ne ra l
a p p lic a t io
C la s s d e s c r ip t io n
n
Direct Simple application; Mainly used for
cheap; complete colour cellulosic fibres;
range; moderate colour can also be
fastness but can be applied on rayon,
improved by after- silk & wool.
treatment with copper
salts & cationic.
6. 6
DIRECT DYES
• Direct dyes for Cotton, Viscose, Silk & Nylon
• Easy to dye - require only cooking salt & very
hot to boiling water.
• Dyes have a good light fastness but only
moderate wash fastness .
• It is possible to improve on wash fastness by
after-treatment of dyed article with dye-fixing
agent.
• These dyes are principally used for “not so
expansive” products or product with fewer
washes such as T-shirts, curtains & theatre
productions.
7. 7
DIRECT DYES
Yellow Pink Brown Turquoise
Orange Red Violet Black
Forrest
Fushia Grey Green
Green
Scarlet Blue Wine China Blue
8. C lassification of dyes
8
M a in
D ye G e ne ra l
a p p lic a
C la s s d e s c r ip t io n
t io n
Azoic Complicated application; limited Mainly
(Naphthol) colour range (red, orange, navy applied on
among the best); bright shade at cellulosic
moderate cost; generally good fibres,
wet fastness but moderate to especially on
poor dry cleaning & rubbing brilliant red
fastness; also called naphthol shade.
dye due to the use of naphthol,
or ice colour because of the
usage of ice during application.
Introduction to Coloration & Finishing
9. 9
Azo Dye Synthesis
Coupling
• Blue component can be
coupled with yellow or
green component to form
two different dyestuffs.
10. 10
AZOIC DYES
• The word 'Azoic' is the distinguishing name
given to insoluble azo dyes that are not applied
directly as dyes, but are actually produced
within the fibre itself.
• This is done with impregnating the fiber with
one component of the dye, followed by
treatment in another component, thus forming
the dye within the fiber.
O
HO C NH
NH2
CH3 NO 2
11. 11
AZOIC DYES
• The formation of this insoluble dye within
the fabric makes it very fast to washing.
• The deposition of the dye on the surface
of the fibre produces poor rub fastness,
but once the loose dye is removed by
boiling the fabric in soap, the dyeing
becomes one of the fastest available.
12. 12
AZOIC DYES
• Normally it is dyed in cold for all natural
fibers
• Naphtol dyes are not sold in the form of a
"finished dye" but in form of their
components (Insoluble azo base & fast
colour coupling compound) which
combine on the fibre to produce a water
insoluble azo dye of exceptional fastness
properties.
13. The following chart of basic range shows only a very limited number of colours13
that can be obtained by using combinations of Naphtol & Diazo.
DIAZO SALT NAPHTOL
G D or AS BO BT GR
CHROME PALE
ORANGE GC ORANGE RED ORANGE APRICOT
YELLOW BROWN
CADMIUM
RED RC BRILLIANT RED DEEP RED
YELLOW
YELLOW CRIMSON
RED B CRIMSON
OCHRE LAKE
REDDISH
BORDEAUX GP CLARET BORDEAUX
YELLOW
CHROME
VIOLET B VIOLET DARK VIOLET
YELLOW
GOLDEN DARK
BLUE BB OR 3B BLUE NAVY BLUE GREEN
YELLOW BROWN
GREEN BB RED RUST BLUE GREEN DARK GREEN
GREEN GT LEAF GREEN BLUE GREEN
Introduction to Coloration & Finishing
BLACK B BLACK BLACK BLACK
14. C lassification of dyes
14
D ye M a in
C la G e n e r a l d e s c r ip t io n a p p lic a t i
ss on
Vat Difficult to apply (requires reduction Commonly
treatment to make soluble in water & used for high
oxidation to resume insoluble state quality cotton
after dyeing); most expensive; goods, e.g.
incomplete colour range (strong in towel; specially
blue & green but weak in brilliant used in the
red); good all round fastness except dyeing of
indigo & sulphurised vat species; denim fabric.
tending to decrease in popularity due
to increasing use of reactive dyes.
Introduction to Coloration & Finishing
15. 2004 15
VAT DYES
• INDIGO, probably the oldest dye
known to man, is one of the most
important members of this group.
• Natural indigo extracted from the
plant 'Indigofera tinctorie' was
used by the Egyptians in 200 BC.
• The first synthetic indigo was
introduced to the textile trade in
1897 & had the effect of
completely replacing the natural
product.
16. 16
VAT DYES
• Although the vat dyes may be divided into 3
chemical groups, they are similar in that they are
insoluble in water & become water soluble
when reduced in the presence of an alkali.
• After dyeing, the fabric is oxidized & the dye
again becomes water insoluble.
• Because of the time consuming & costly
procedure in reducing vat dye into a water-
soluble complex, dye manufacturers have
produced a stabilized water-soluble vat dye.
17. 17
VAT DYES
• This dye can be applied to
cotton & viscose rayon by
the methods used by
applying direct cotton
dyes.
• After the dyeing, a simple
treatment restores the vat
dye to its normal insoluble
state.
18. 18
VAT DYES - USE:
• Vat dyes are used in cotton dyeing where high
wash & boil fastness required.
• Because of the high alkali concentration in the dye
bath, pure vat dyes cannot be used on animal
fibres, (wool, natural silk, & various hairs).
• Solubilized vat dyes, not requiring the presence of
alkali, can be used for dyeing on animal fibres.
• Bright red is absent in vat dye range.
• Because they are dyed at low temperatures, they
are used in Indonesian batik dyeing for green
shades.
19. 19
VAT DYES
• When the ultimate in wash & boil fastness
is required.
• Also used to dye over fibre reactive dyes for
multi-layered dyeing.
YELLOW GREEN
ORANGE OLIVE B
RED BROWN
BLUE NAVY
VIOLET BLACK
Introduction to Coloration & Finishing
20. C lassification of dyes
20
M a in
D ye G e ne ra l
a p p lic a t io
C la s s d e s c r ip t io n
n
Sulphur Difficult to apply (application Mostly used for
similar to vat dyes); cheap heavy cellulosic
particularly for dark shade; goods in dark
incomplete black, navy, khaki shades.
& colour range (strong in
brown but no bright shade);
poor washing & rubbing
fastness & sensitive to
chlorine; may cause fabric
rendering of cellulose upon
storage (aging). to Coloration & Finishing
Introduction
21. 21
SULPHUR DYES
• The first Sulphur dye was discovered in France
in 1873, & further work done by Raymond Videl
enabled the manufacture of 'Videl black".
• Its outstanding fastness to light, washing &
boiling far surpassed any cotton black known at
that time.
• The general disadvantage of the Sulphur dyes
that they produce dull shades & lack a red.
22. 22
SULPHUR DYES
• The main advantage lays in their
cheapness, ease of application & good
wash-fastness.
• In their normal state, Sulphur dyes are
insoluble in water but are readily soluble in
the solution of Sodium Sulphide.
• In this form they have high affinity to the
all cellulose fibres.
23. 23
SULPHUR DYES - USE:
• The use of Sulphur dyes is restricted to
dull brown, Khaki & Navy shades,
where a good wash but not boil-fastness
is required.
• Most Khaki & Navy overalls are dyed
with Sulphur dyes.
24. 24
SULPHUR DYES - USE:
• An outstanding member of this family is
Sulphur black.
• It dyes all cellulose fibres, but particularly linen &
jute, to a lustrous & deep black with excellent
wash & light fastness.
• Sulphur dyes are dyed from a dye bath
containing Sodium Sulphide & common or
Glaubers Salt, & are oxidized by airing or with
some oxidizing agents (Sodium Bichromate or
Hydrogen Peroxide) in a fresh bath.
25. 25
C lassification of dyes
D ye G e ne ra l M a in
C la s s d e s c r ip t io n a p p lic a t io n
Reactive Easy application; Commonly used for all
moderate price; complete cellulosic goods
colour range; good especially in knitted
fastness due to direct fabric batchwise
reaction with fibres. dyeing; selective dyes
can also be applied on
wool, silk & rayon;
increasingly used in
printing due to good
fastness.
26. 26
REACTIVE DYES
• This is an entirely class of dye introduced
to the market in 1956.
• They react chemically with the fibre being
dyed & if correctly applied, cannot be
removed by washing or boiling.
27. 27
REACTIVE DYES
• The main feature of the
dyestuff is its low affinity
to cellulose; therefore
large amounts of salt are
required to force its
deposition on he fabric.
29. 29
REACTIVE DYES - USE:
• Reactive dyes are used
where bright dyeing with
high light & wash fastness
is required.
• Cold dyeing is used
extensively in batik work.
• Although some reactive
dyestuffs have been
specially modified to dye
wool, their main usage is
in dyeing cotton linen &
viscose rayon.
30. Yellow 2GL 30
Golden Yellow 2RL
REACTIVE DYES Orange 2R
Scarlet
• Cold water fibre Red BG (primary)
reactive dyes, suitable Red 4B (bluish red)
for dyeing on cotton, Red 8B (magenta)
silk, jute, rayon & Rubinole 5B
hessian. Brilliant Blue 2R
Brilliant Blue BL
• Cannot be used on
Violet 2R
synthetics or fabric Turquoise 2G
that has been coated Navy GRL
with resin or drip-dry Brown 2R
finish. Brilliant Green BL
Black B (blue base)
Black 2B (green base)
31. 31
Dye for Protein Fibres:
• Acid Dyes
• Metal-
complex Dyes
• Chrome Dyes
32. 32
C lassification of dyes
M a in
D ye G e ne ra l
a p p lic a t i
C la s s d e s c r ip t io n
on
Acid Easy application; Commonly used
complete colour for wool, silk &
range with very nylon.
good bright shades;
fastness properties
may vary among
individual dyes.
33. 33
ACID DYES
• These dyes comprise a large number of dyes used
for the dyeing of wool, silk & nylon.
• They vary considerably in their basic chemical
structure, but have one common feature - they dye
from an acid dye bath.
• All acid dyes can be grouped in 3 sub groups:
a. Level dyeing acid dyes
b. Acid milling dyes
c. Pre-metalized dyes
34. 34
ACID DYES
a. Level dyeing acid dyes:
• These dyes produce bright dyeing.
• The main feature is their good leveling
properties.
• They are dyed from a dye bath containing
strong acids (Sulphuric or Formic acid).
• These dyes exhibit low wash & light
fastness.
35. 35
ACID DYES
b. Acid milling dyes:
• Selected because of their high & light fastness & are
extensively used for dyeing woolen fabrics that are
subsequently milled.
• These dyes require great care in application because
uneven dyeings are difficult or impossible to rectify.
• The dye bath requires the presence of weak acid
(acetic acid) or acid releasing salts (ammonium
sulphate or ammonium acetate) from which acid is
liberated during dyeing.
Introduction to Coloration & Finishing
36. 36
ACID DYES
c. Pre-metalized dyes
• These dyes represent an extension of
mordant dyes.
• The metal component being already
incorporated in the dye during manufacturing
process.
• Very good light fastness even in pale shades
Introduction to Coloration & Finishing
37. 37
ACID DYES - USE:
• The family of acid dyes is very large & diverse,
varying widely in their methods of dyeing,
application & end use of the dyed fabric.
• A choice of dyes should be made considering
sometimes-incompatible factors: - level dyeing,
fastness, brightness & ease of application.
• Care must be taken to use the appropriate method
as prescribed for a given dye.
• A number of acid dyes are also used to dye nylon.
38. 38
ACID DYES for Wool, Nylon & Silk
• Selection of milling & pre-metallised
dyes. Dyeing at boil with addition of
Acetic Acid. Bright strong colours.
Mixes of primary colours (*) produce
large range of tertiary colours. Dyes
have very high light & wash fastness.
39. 39
C lassification of dyes
M a in
D ye G e ne ra l
a p p lic a t i
C la s s d e s c r ip t io n
on
Metal- Relatively difficult to apply; Mainly used
complex expensive; complete colour for wool &
range but duller shade than Nylon.
acid dyes; good fastness due
to high molecular size &
metal complex structure.
40. 40
C lassification of dyes
M a in
D ye G e ne ra l
a p p lic a t io
C la s s d e s c r ip t io n
n
Chrome Complicated Mainly used for
Mordant application; expensive; wool products
complete especially for the
colour range but very end use of carpet.
dull shade; good all
round fastness.
41. 41
Dye for Other Fibres:
• Disperse
Dyes for
Polyester,
Acetate
• Cationic Dyes
for Acrylic
42. 42
C lassification of dyes
M a in
D ye
G e n e r a l d e s c r ip t io n a p p lic a t i
C la s s
on
Disperse Require skill in application (either Mostly used
by carrier or under high for polyester
temperature); moderate price; & acetate; can
complete colour range; limited also be applied
solubility in water (normally on nylon &
dispersed in water for Acrylic.
application); good fastness
after reduction clearing treatment;
sublimation property.
Introduction to Coloration & Finishing
43. 43
DISPERSE DYES
• The introduction of a new regenerated cellulose acetate
fibre in 1920 led to the necessity to develop an entirely new
range of dyes.
• It was found that acetate (or Celanese) fibre had hardly any
affinity for water-soluble dyes.
• A new dyeing principle was introduced: dyeing with water
dispersed coloured organic substances.
• These finely coloured particles are applied in aqueous
dispersion to the acetate material & actually dissolved in the
fibres.
44. 44
DISPERSE DYES - USE:
• Basically developed for dyeing of acetate
fibres, Disperse dyes are also used for
dyeing of polyamide (Nylon) & acrylic
(Orlon & Acrylan) fibres.
• With the addition of 'carriers' or swelling
agents these dyes are also used in dyeing
of Polyester (Terylene, Dacron, etc.)
45. 45
C lassification of dyes
M a in
D ye G e ne ra l
a p p lic a t i
C la s s d e s c r ip t io n
on
Basic Careful application required Mainly used for
(Cationic) to prevent unlevel dyeing & acrylic.
adverse effect in hand-feel;
complete colour range with
very good brilliant shades.
46. 46
CATIONIC & BASIC DYES
• MAUVENE, the first to be discovered by Perkin,
was a basic dye & most of the dyes which
followed, including magenta, malachite green
& crystal violet, were of the same type.
• “Basic dyes” dye wool & silk from a dye bath
containing acid but dye cotton fibres only in the
presence of a mordant usually a metallic salt
that increases affinity of the fabric for the dye.
• Basic dyes include the most brilliant of all the
synthetic dyes known, but unfortunately they
have very poor light & wash fastness.
47. 47
CATIONIC & BASIC DYES - USE:
Basic dyes will dye wool & silk from an acid bath &
are used where brightness is of prime
consideration.
With the introduction of cotton dyes possessing
higher fastness properties their use for dyeing
cotton has diminished.
Basic dyes are used extensively for dyeing cut
flowers, dried flowers, also dyeing jute sisal, coir
& wood (toys).
With the introduction of acrylic fibre a new range of
'modified' basic dyes – “cationic dyes” were
perfected for dyeing of this material.
48. 48
Cationic dyes
• Cationic dyes for dyeing acrylic (Acrilan, Courtelle, Orlon)
paper, wood & dried flowers.
Also used for dyeing silk & silk flowers in very brilliant
colours.
YELLOW BLUE
ORANGE TURQUOISE
RED VIOLET
PINK GREEN
RHODAMINE to Coloration & Finishing
Introduction BLACK
49. 49
Chronology of Dye Companies
ICI Zeneca BASF
Mobay Miles Bayer
DyStar
DyStar
Sumitomo
Hoechst
Sodyeco
Sandoz Sandoz Clariant
Ciba + Geigy Ciba-Geigy Ciba
Crompton and Knowles Yorkshire
50. 50
Colour Formulation
• The choice of a specific colour for a particular material is
the responsibility of the textile designer or colourist who
perceives the colour to be in conformity with the fashion
requirement.
• It is the job of the textile dyer to match the designer ’s
colour with the proper dyes or pigments as well as to meet
the colour fastness requirements for the specific end-use of
the material.
• In brief,the designer ’s role is part of the world of artistry &
creativity, while the dyer ’s role is in the world of science &
technology.
51. 51
Colour Formulation
• Matching of colour shades by
the dyer requires the skilful
blending & formulation of
different dyes & pigments, as
well as an understanding of
the nature of fibres & the
numerous chemicals needed
to carry the dyeing process.
52. 2004 52
Colour
Formulation
• Colour match recipes are first developed on a small
laboratory basis.
• Once the dyer has formulated a colour match &
achieved a satisfactory sampling (often known as the
lab-dip), this becomes the standard which all future
dye lots or batches must follow.
53. 53
Colour Formulation
• In actual production, however, each dye lot is
more or less different in shade from all other
lots.
• This lot-to-lot shade variation is caused by
several factors such as differences in dyes /
auxiliaries concentration, fabric lots & different
dyeing machine settings, etc.
54. 54
Colour Fastness
• A good dye must withstand the subsequent treatment (e.g.
laundering, dry cleaning, etc.) or environmental wearing
(e.g.rubbing,light exposure, etc.).
• The degree to which a dyed material can withstand such
treatments & wearing is called colour fastness.
• No dye or pigment is fast in all colour fastness.
• Only a careful selection & formulation of dyes &
auxiliaries can result in a desirable dyeing, & conform with
the colour fastness requirements.
56. 56
Principle of using Grey Scale
• The result of a colorfastness test is rated
by visually comparing the difference in
color or the contrast between the un-
treated & treated specimens with the
differences represented by the Scale.
• The colorfastness grade is equal to the
gray scale step which is judged to have
the same color or contrast difference.
59. D ye classes’ colour fastness 59
properties
Introduction to Coloration & Finishing
60. 60
Application of
Pigments
Popular especially in printing.
Advantages :
• easy to apply with good shade matching from
lot to lot;
• full colour range; &
• can be applied on all textile fibres & their
blends.
