IJFTR 28(4) 450-455

Indian Journal o f Fiore & Tex tile Research
Vol. 28. Dece mber 2003, pp. 450-455
Pseudo single-bath process for ambient temperature bleaching and
reactive dyeing of jute
S N C hattopadh yay, N C Pan & A Day"
Chemi cal & Biochemical Processing Division, National Institute of Research on Jute & Alli ed Fibre Technol ogy.
12 Regent Park , Ko lkata 700 040, Ind ia
Received 19 Jlllle 2002; accepted 10 September 2002
Grey j ute fi bre has been bleached at ambient temperature using hydrogen peroxide and th en co ld dyed with Proc ion
Red M8B and Remazo l Ye llow FG dyes by four di ffe rent process seq uences. name ly conve nti onal two-step process, trlle
si ngle-bath process , pseudo single-bath process and pseudo si ngle-bat h process using spe nt bleach bath . The e ffect of
process sequ ences o n colour yield of dyed j ute fi bre has been evaluated usi ng computer colour matching system. It is
obse rved th at the colour yield by pseudo si ngle-bath process is we ll co mparab le with that of th e co nventio nal two-step
ambi ent temperature bleach ing and cold reactive dye ing process. It is also observed that th e colour yield is max imum in case
of pseudo si ngle-bath process and mi nimum in case of true single-bath process. The process o f dyei ng has no effect on A """
value whi ch confi rms no alterati on in the hue and tone of any sample dyed wi th reactive dye by d ifferent sing le-bath
processes. The wash fas tn ess is satisfactory in all th e processes .
Keywords : Ambient temperature bleac hing, Jute fi bre, Pse udo single-bath process, Reacti ve dye in g
1 Introduction
Decreas ing trend in the use of jute fibre in the
traditional sector, like packaging, is being well
compensated by the increasing use of jute in the
di versified sectors. Jute is now finding its use in several
di versified applications like curtains, uphol stery, bags /
luggage, handicrafts and even in apparel sector. So, the
wet process ing of jute has occupied very important
pos iti on in jute industry as the diversifi ed use needs
attracti ve look where bleac hing, dyeing and fi ni shing
are must. But the processi ng of jute requires a lot of
energy, water, chemicals, etc. which not only increases
the cost of processing but also leads to environment
pollution through efflu ents. Several works have been
done in the recent past, like ambient temperature
bleac hing 1-4, foam application technology and singlebath bleaching-dyeing to combat the above problems.
Considering the energy problem, environment
pollution, ease of process ing in the rural sector, etc., the
present work has been devised in such a way that all
the process ings like bleaching and dyeing will be
can-ied out at ambient temperature. Moreover, the
attempts have also been made to carry out both the
processes in the same bath. Al so, the spent liquor after
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ambi ent temperature bleaching 5 has been re used for
another batch of ambi ent temperature bleac hing. Th is
is an integrated approach suitable spec ifica ll y for rural
small -scale sector where all the resources like thermal
energy, electrica l energy, skill ed manpower, adequa te
finance, easy ava il ability of chemica ls, water, etc. are
scare.
2 Materials and Methods
2.1 Materials
Grey jute fibre of TD-3 vari ety having f ineness of
2.4 tex was used fo r the ex peri ment.
The following chemi ca ls of anal yti ca l grade we re
used for the stud y : hydrogen peroxide, tri sodium
phosphate, sodium hydrox ide, sodium ca rbo nate .
sodium hydrosulphite , sodium persulph ate, sod ium
si li cate, magnes ium sulphate he ptahydrate, non-i oni c
detergent (Ultravon JU) and acetic aci d.
Reacti ve dyes Proc ion Red M 8B (n ucleoph ilic
substitution type) and Remazol Ye ll ow FG
(nucleoph ilic additi on type) were used fo r dye in g of
jute fibre.
2.2 M ethods
2.2.1 Conventional Bleaching of G r ey Jute Fih re
Bleachin g of grey j ute fibre was carried ou t in a
closed vessel at 90°C fo r 2 h, keepi ng the ma terial- toli q uor rati o at 1: 20, us ing hydrogen perox ide ( I vo l).
CHATTOPADHYAY el al. : AMBIENT TEMPERATURE BLEACHING & REACTIV E DYEING OF JUTE
trisodium phosphate (5 gIL), sodium hydroxide (1
gIL), sodium silicate (10 gIL) and non-ionic detergent
(2 gIL). After bleaching, the fibre samples were
washed thoroughly in cold water, neutralized with
acetic acid (2mJlL), again cold washed and finally
dried in air.
2.2.2 Ambient Temperature Bleaching of Grey Jute Fibre
Jute fibre intended for ambient temperature
bleaching was dipped in a solution containing
hydrogen peroxide (10 vol), sodium silicate (20 gIL),
sodium hydroxide (20 gIL), trisodium phosphate
(5glL), sodium persulphate (lOglL), magnesium
sulphate heptahydrate(0.5 gIL) and Ultravon JU (10
gIL), keeping the material-to-liquor ratio at 1:3, and
queezed to give 100 % wet pick-up. The samples
were put in a plastic bag and kept as such for
overnight. The samples were then washed, neutralized
with acetic acid (2 mJlL) and washed again in cold
water before drying at room temperature.
2.2.3 Dyeing of Ambient Temperature Bleached Jute Fibre
Ambient temperature bleached jute fibres were
dyed with two different reactive dyes , namely Procion
Red M88 and Remazol Yellow FG, using the
following procedure :
Pracion Red M8B - Dye bath was made with dye
(4%) and Glauber' s salt (60 gIL), keeping the
material-to-liquor ratio at 1:20 . The bleached fibre
samples were dipped into the dye bath and kept for 1
h with stirring at 30°C. After this treatment, sodium
carbonate (20 gIL) was added in the same bath and
kept for 45 mjn under the same condition . Thereafter,
the samples were washed with cold water, soaped
with Ultravon JU (2 gIL) for 15 min at boil followed
by usual washing and drying in air.
Rernazo! Yellow FG - Dye bath was made with
dye (4%) and Glauber' s salt (80 gIL), keeping the
material-to-liquor ratio at 1:20 . The bleached fibre
samples were dipped into the dye bath and kept for 20
min with stilTing at 30°C. After this treatment, the
sodium hydroxide (4 gIL) was added in the same bath
and kept for Ih under the same condition. Thereafter,
the samples were washed with cold water, soaped
with Ultravon JU (2 gIL) for 15 min at boil followed
by usual washing and drying in air.
2.2.4 Single-Bath Bleaching - Dyeing of Jute Fibre
Ambient temperature bleaching and reactive
dyeing of jute fibre was carried out by using three
different process sequences, namely true single-bath
process, pseudo single-bath process and
single-bath process using spent bleach bath.
451
pse ud o
2.2.4.1 True Single-Bath Process
For ambient temperature bleaching, grey jute fibre
was dipped in a solution containing hydroge n
peroxide 00 vol), sodium silicate (20 giL ), sodium
hydroxide (20 gIL), tri sodium phosphate (5g/L ).
sodium persulphate (10 gIL), magnesium sulph ate
heptahydrate (0.5 gIL) and Ultra von JU ( 10 gi L ).
keeping the material-to-liquor ratio at 1:3 . After
keeping the bath as such for 2 h, sod ium
hydrosulphite ( 10 gIL) was added to it and the
solution was stirred for 15 min .
Procion Red M8B (4%) and Glauber ' s salt (60 giL )
were added to the above bleach bath and kept for I h
with stirring at 30°C. After this treatment , the sodium
carbonate (20 gIL) was added in the same bath and
kept for 45 min under the same condition . Thereafte r.
the samples were washed with cold water. soa ped
with Ultravon JU (2 giL) for 15 min at boil fo ll owed
by usual washing and drying in air.
Remazol Yellow FG (4 %) and Glauber 's salt
(80 gIL) were added to the above bleach bath and ke pt
for 20 min with stirring at 30°C. After this trea tme nt.
the sodium hydroxide (4 gIL) was added in the sa me
bath and kept for 1 h under the same conditi on.
Thereafter, the samples were washed with cold water.
soaped with Ultravon JU (2 gIL) for 15 min at bo il
followed by usual washing and drying in air.
2.2.4.2 Pseudo Single-Bath Process
For ambient temperature bleaching, grey jute fi bre
was dipped in a solution containing hydrogen perox ide
(10 vol), sodium silicate (20 gIL), sodium hyd rox ide
(20 gIL), trisodium phosphate (5glL), sodium
persulphate (10 gIL), magnesium sulphate heptahydrate
(0.5 gIL) and Ultravon JU (10 gIL), keeping the
material- to- liquor ratio at 1:3, and squeezed to give
100% wet pick-up. The samples were put in a pl asti c
bag and kept for 2 h .The bleached fibre (with out
washing) was then put in a separate bath containing ten
times its volume of water (M:L :: 1:10). Sodium
hydrosulphite (3 gIL) was added to the bath and kept
for 15 min with continuous stirring.
Procion Red M8B dye (4 %) and Glauber's sa lt (60
giL) were added to the above bath and kept for I h
with stirring at 30°C. After this treatment, the sodium
carbonate (20 gIL) was added in the same bath and
kept for 45 min under the same condition. Thereafter.
the samples were washed with cold water, soaped
IND IAN J. FIBRE TEXT. RES., DECEMBER 2003
452
with Ultravon JU (2 gIL) for 15 min at boi l fo llowed
by usual washing and drying in air.
Re mazol Ye ll ow FG dye (4 %) and G lauber's salt
(80 giL ) were added to the above bath and ke pt for 20
min w ith stirring at 30°C. After thi s treatment , the
sodium hydrox ide (4 gIL) was added in the same bath
and ke pt for 1 h under the same condition. Thereafter,
the sa mples were washed with cold wate r, soaped
w ith U ltravon JU (2 gIL) for 15 min at boil fo ll owed
by usua l washing and drying in air.
2.3.2 A 1IIax> Reflectance and KIS Values
Spectrascan-5100 (R) computer colour matc hing
system was also used to measure A. max> re fl ectance and
KIS va lues of different types of reacti ve dyed jute fib re
samples using relevant softwares and following formula:
K I S = l (J -R) 2 I 2R ]
DC
C
where K is the coeffi c ie nt of absorption ; S. the
coefficient of sca tte ring ; R, the re fl ecta nce of
substrate at A. max; and C, the concentration of dye. T he
K I S value is viewed as an index of d ye upt ake.
2.2.4.3 Pseudo Single-Bath Process using Spent Bleach Bath
The liquor left out after ambient tempe rature
bleaching, as described in sec tion 2.2.2, was re used fo r
the preparation of second batch of the sa mpl e. Grey
jute fibre intended for ambient temperature bleaching
using spe nt liquor was dipped in the above liquor and
squeezed to give 100% wet pick-up. The samples
we re put in a plastic bag and ke pt for 2 h. The
bleac hed fibre (without washing) ·was the n pu t in a
sepa rate bath containing ten times its volume of wate r
(M:L:: I: 10). Sodium hyd ros ul phite (2 gIL) was added
to the bath and kept for 15 min with continuous
stirring. The dyeing was carried out in the same way
as me ntioned in sec tion 2.2.4.2.
2.3.3 Wash Fastness
All the reac tive dyed jute fibre sa mpl es we re
subjected to wash fastness tes ts in a launder-O-meter
as per IS:3361-1979 (ref.6) . Wash fastness ratin gs of
a ll the dyed jute fibre samples were eva lu ated w ith the
help of computer colour matching system.
3 Resul ts and Discussion
Table 1 shows that both the white ness and
brightness indices are poor in case of grey jute fibre
but after bleaching both the indices improve
cons ide rably . There is a substa nti al dec rease in
ye llowness index after bleaching. Co nve nti onal
bleaching process prod uces bette r bleaching e ffect
compa red to ambient te mpe rature bleach ing process.
The whiteness a nd brightness ac hi eved after amb ien t
te mperature bl eac hing are sa ti sfac tory enou gh fo r
subsequent dyeing operation.
Table 2 shows that the ambient temperature bl eac hed
jute fibre produces higher KIS value as compared to
conventiona l bleached jute fibre, indicating that the
2.3 Determination of Physico-chemical Propert ies
2.3.1 Whiteness, Yellowness and Brightness Indices
Whiteness index (HUNTER sca le), ye llowness
ind ex (ASTM D 1925 sca le) and bri ghtn ess index
(TAPPI 45 sca le) of grey, conventional b leac hed and
amb ien t te mpe rature bleac hed jute fibre samp les were
mea sured by the Spectrascan-5100 (R) computer
co lour matching syste m using re levant softwares.
Table I Bleaching
age nt uscd
Bleach ing
process
Nil
Hydrogen peroxide
Nil
Conventional
Hydrogen peroxide
Ambient temperatu re
76.27
Sample
Grey
Bl eached
Bl eached
Evaluati on of fibre quality
Table 2 Parameter
Wh iteness
index
(HUNTER)
Yellowness
index
(ASTM 0 1925)
Bright ness
index
(TA PPI45)
53 .99
46.21
23.96
83 17
18.82
64.59
2 1.9 1
53.99
Effect of different bleaching processes on dyeing behav iou r of jute fibre
Procion Red M8B
Ambie nt
Conventional
temperature
bleaching
bl eaching
Remazol Yellow FG
Conventional
Amoi ent
bleaching
temperature
bleaching
A Illax , nm
550
550
420
420
Refl ectance
5.5 1
14. 14
13 .3 I
KIS value
8. I I
3-4
4.93
9. 16
2.6 1
4
3-4
2.91
3-4
Wash fastness
453
CHATTOPADHYAY el at.: AMBIENT TEMPERATURE BLEACHING & REACT IVE DYEING OF JUTE
colour yield is more in case of ambient temperature
bleached jute fibre. This finding is true for both Procion
Red M8B ( substitution type of reactive dye) and
Remazol Yell ow FG ( addition type of reactive dye).
The higher dye uptake may be due to the high alka line
condition used during ambient temperature bleaching.
Wash fastness property is found to be good in all the
cases.
In true single-bath process (Table 3), the colour
yield is very poor when sodium hydrosu lphite is not
added for counteracting the oxidising effect of
hydrogen peroxide bleached bath and alka li is not
added during the fixation stage of reactive dye. Some
minor improvement in colour yield is observed when
sodium hydrosulphite or alkali is added alone. But
more improvement in colour yi e ld is observed whe n
both sodium hydrosulphite and alkali are added in the
bath . This finding is true for both the reactive dyes
studied . In all the cases, the colour yield is very poor
when true single-bath process is followed. Wash
fastness of all the samp les is moderate. Low liquor
ratio, high alkali concentration and very hi gh
oxidising agent concentration may be respon s ibl e fo r
poor colour yield. Hence, it was decided that the tru e
single-bath process wi ll not serve the purpose and the
idea of pseudo single-bath process was emerged .
In pseudo single-bath process, as the fibre wa s not
washed after bleaching, it carried a portion of excess
alkali to the dye bath. So, alkali was not add ed in the
bath during fixation stage of react ive dyes . The
colour yield of dyed samples was found to be poo r in
both types of p seudo single-bath processes. For the
improvement in fixation of dyes, the alkali wa s added
to the dye bath during fixation stage and the colour
yield was found to be sati sfactory in all the cases
whether it is pseudo sing le-bath process or pse ud o
single-bath process using spent bleach bath (Table 4 ).
To optimize the concentration of reducin g agenl
after bleachin g both in case of pseudo sin gle-ba th
process (Table 5) and pseudo single-bath process
Table 3 - Effect of intermediate addition o f reducin g agent after bleaching and alkali during fixation stage of reacti ve d ye in g o n dyc ing
behaviour o f jute fibre using true single-bath process at ambi ent temperature
Addition
of sodium
hydrosulphite
RFL -
Addition
of alkali
A.
ma"
Procion Red MSB
RFL
KI S
nm
Wash
fastness
A IIll'
Remazol Yell o w FG
RFL
KIS
No
No
550
37 .34
0.53
3
420
47 .39
0 .29
3-4
No
Yes
550
33 .76
0 .65
2-3
420
43.47
0 .37
:1
Yes
No
550
32 .SS
0.69
3
420
43.42
0 .3 7
2-3
Yes
Yes
550
26.46
1.02
3-4
420
3 1.24
0 .76
3-4
Reflectance
Table 4 - Effect of alkali during fixation stage of reactive dye in pse udo single- bath process and pseudo singlc-bath
process usin g spent bleach bath at ambient tempcrature
<-
W a~h
ras t nc s~
nm
Parameter
Pseudo sin gle-bath process
Procion
Remazol
Yellow FG
Red MSB
With
Without
With
Without
alkali
alkali
alkali
alkali
Pscudo sin gle-bath process usi ng spent bleach hath
Remazo l
Procio n
Red MSB
Yellow FG
With
Withou t
With
Without
alk ali
alk ali
alkali
alk ali
A max , nm
550
6.19
7. 11
550
S.44
4 .97
Rcl1 ectancc
KIS
550
23 .S2
1.22
420
10.05
4 .02
420
27 .02
0.99
550
34 . 17
0 .63
420
420
13.07
2 .S9
4645
0 .3 1
Table 5 - Effect o f reducing agent after bleachin g on dyein g behav io ur o f reacti ve d yes using
pseudo single-bath process at ambi ent temperature
Parameter
0"
A max' nln
Refl ectance
KIS
a Sodium
Procion Red MSB
2 .0"
3.0"
Rcmazo l Yellow FG
2 .0"
3 .0"
5.0"
0"
550
420
420
420
420
5 .0"
550
550
550
23 .S2
12 . 11
6 . 19
6.97
34.42
2609
10.05
12. 13
1.22
3. 19
7. 11
6 .21
0.62
1.05
4 .02
3. IS
hydrosulphite concentration in giL
INDIAN 1. FIBR E TEXT. RES ., DECEMBER 2003
454
Table 6 - Effect of redu cing age nt after bleachi ng on dyeing behaviour of reactive dyes followin g
pseudo single-bath process using spent bleach bath at ambie nt temperature
Parameter
Procion Red M8B
2.0"
1.5"
0"
nm
Re Oectance
Am;.t.'(.
KIS
a
550
30.82
0.79
550
9.61
4.25
550
8.44
4.97
3.0"
0"
550
8.73
4 .76
420
43.44
0.37
Remazo l Yellow FG
2.0"
1.5"
420
14.24
2.58
3.0"
420
13.68
2.69
420
13.07
2.89
Sodium hydrosulphite co ncentration in giL
Table 7 - Effect of differen t single-bath bleaching-dyeing processes at ambient temperature on colour
yield usin g two reactive dyes
Process
A",,,
nm
True single- bath
process
Pseudo single-bath
process
Pseudo single-bath
process using spent
bleach bath
Procion Red M8B
KIS
RFL
fastness
Wash
A max
nm
Remazol Yell ow FG
RFL
KIS
Wash
fastness
550
26.46
1.02
4
420
31 .24
0.76
3-4
550
6.19
7.11
4
420
10.05
4.02
4
550
8.44
4.97
3-4
420
13.07
2.89
3-4
uSing spent bleach bath (Table 6), different
concentrations of sodium hydrosulphite (0,1.5, 2.0,
3.0 , and 5.0 gIL) were used. The colour yield
increased with the increase in sodium hydrosulphite
concentration up to 3 giL in pseudo single-bath
process and up to 2 gIL in pseudo single-bath process
using spent bleach bath . Thereafter, a decreasing trend
in co lour yie ld was observed . Sodium hydrosulphite
reacts with the active hydrogen peroxide remaining
ins ide the fibre and in the bath up to the optimized
concentration . The higher concentration, than the
optimized one, acts on the dyestuff in addition to its
action with oxidising agent , thereby reducing the
colour yield.
Dye ing properties of jute fibre dyed with Procion
Red M8B and Remazol Yellow FG at optimized
condition using different processes are given in
Table 7. It is evident that the colour yield is maximum
in case of pseudo single-bath process and minimum in
case of true single-bath process . By comparing the
colour yie ld s from Table 2 and Table 7 , it is revealed
that the pseudo single-bath process is well comparable
with the conventional two-step process using ambient
temperature bleaching and cold reactive dyeing.
Pse udo single-bath process using spent bleach liquor
produces higher colour yield than that produced by
true sing le-bath process but lower than that produced
by pseudo single-bath process.
4 Conclusions
4.1 Whiteness index produced by ambient te mpera-
ture process is slightly lower than th at produced by
conventional hot bleaching process . The whiten ess
and brightness achieved after ambient temperature
bleaching is satisfactory enough for subseq uent dyeing operation.
4.2 Dyeing of ambient temperature bleached jute fibre produces higher colour yield as compared to conventional bleached jute fibre. This finding is true for
both Procion Red M8B (substitution type) and Remazol Yellow FG (addition type) dyes. High alkaline
condition during ambient temperature bleaching results in swelling of fibre which ult imately g ives better
colour yield.
4.3 In true single-bath process , the addition of redu cing agent (sodium hydrosulphite) after bleaching and
that of alkali during fixation stage is must. But the
colour yield is very poor when true si ngle-bath process is followed for ambient temperature bleaching and
cold reactive dyeing. Low liquor ratio, high alka li
concentration and very high oxidizing agent concentration may be responsible for poor colour yield. So.
the true single-bath process was not found to serve the
purpose and the idea of pseudo single-bath process
was emerged.
4.4 In pseudo sing le-bath process, the addi ti on of
3 gIL sodium hydrosulphite after bleaching and the
..
CHATTOPADHYAY
el
455
al.: AM BIENT TEMPERATURE BLEACHING & REACTIVE DYEI NG OF JUTE
required amount of alkali for fixation of reactive dye
is must. Colour yield produced by pseudo single-bath
process is well comparable with that produced by
conventional two-step process using ambient temperature bleac hing and cold reactive dyeing.
4.5 Pseudo single-bath process using spent bleach
bath produced higher colour yield than that produced
by true single-bath process but it is lower than that
produced by pseudo single-bath process. In this case,
the optimized concentration of sodium hydrosulphite
is 2 giL to achieve maximum colour yield. As the
spent bleach bath can be reused , thi s process becomes
simple and economic with minimum effluent disposal
problem as after spent liquor bleaching there is hardl y
any liquor left out in the bath for disposa l.
4.6 Wash fastness ratings are sati sfactory
In
a ll the
processes .
References
I Pandey S N, Chattopadh yay S N & Bas u G. Indian .I Fibre
Text Res, 20 ( 1995) 102.
2 Basu G & Chattopadhyay S N, Indian J Fibre TexT Res. 2 1
( 1996) 2 17.
3 Chattopadhyay S N , Pan N C & Day A. TexT Trends.
XLlII(200 I) 23.
4 Pan N C. Chattopadhyay S N & Day A. TeXT Asia.
XXXII (2001 ) 40.
5 Pan N C, Chattopadhyay S N & Day A, TexT Ind Trade .I.
39(200 I )37.
6 IS: 3361-1979, lSI Handbook oj TeXTile TeSTing ( Bureau of
Indi an Standards, New Delhi ), 1982.

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