Yellowing of Cotton Because of Softeners

LABEESH KUMAR(2015TTF2388)

Hypothesis:In LNJ Denim where I was working previous year, there was a huge problem of Shade defects

due to softeners. So I decide to couple my colour knowledge with my work experience and design this experiment.

Here I divide my experiment in two parts-1. To study the yellowing effect of different kinds of softeners on cotton fabric

2. To study the softening and yellowing effect of different cationic softener concentration on cotton fabric, by measuring Bending length, absorbency time (Drop test), Whiteness index(CIE WI) and Yellowing Index (YI E313).

Further Scope:We can optimize the softening process by CCD (Central composite design) technique by taking the various parameters like pH, Concentration, Temperature etc.

AIM-1 • To study the yellowing effect of different kinds of softeners on cotton fabric.

SOFTENING • MECHANISM

CAUSES OF YELLOWNES

S

INSTRUMENTAL GENERAL

INFORMATION

RESULTS & DISSCUSSION

• EFFECT ON YELLOWNESS• EFFECT ON WHITENESS

INFERENCES

Aim-1:

• To study the yellowing effect of different kinds of softeners on cotton fabric.

FABRIC SUBSTRATE

Why softener…?

Softness ↑Handle ↑Drape ↑Cutting qualities ↑Sewing qualities ↑static build-up ↓

FABRIC SUBSTRATE

MECHANISMS OF SOFTENING: Orientation and

bonding

It’s a surface effect.

New surface of Mol. Chains,

Provide Softening

Reduce inter fibre friction

We touch the tail of the molecule

Hydrophobic tail

Cationic softener

-ve zeta potential on cotton surface

Cationic softeners

Non-ionic softener

Anionic softener

Silicone softeners

1. FIBER AGEING:Continuous exposure and photo oxidation causes yellowness increase

2. ENVIRONMENTAL POLLUTANTSYellowing by ozone -Earth surface Ozone oxidizes the Indigo dye into Isatin and Antranalic

acid, which are yellow in colourOxides of nitrogen-Nitrogen oxides react with the residues present on the surface of the

fabric and cause yellowness of Nylons

3. CHEMICAL ADDITIVESSoftenersOptical brightening agent- Over usage, High heat or high humidity

CAUSES OF FABRIC YELLOWING:

YELLOWING DUE TO SOFTENERS

• Most commonly used softeners are the amine based (N-H) cationic and silicone softeners

• Reacts with free Cl, and form chloramines (yellow in colour)

• These Amines oxidise at higher temperature to form oxides of nitrogen (yellow in colour)

General information about Instruments:

Whiteness Index-CIE

RECIPE & PROCEDURESample Chemicals Concentration(%)

1 Cationic 10

2 Cationic 20

3 Non-ionic 10

4 Non-ionic 20

5 Silicon 10

6 Silicon 20

Weigh the samplesPrepare the softener

solutions with M:L = 1:40

Pad the samples by padding mangle

Dry the samples at 105 C for 2 min.⁰

Testing the treated and untreated samples at Spectrophotometer .

Sample name L* a* b* WI-CIE YI-E313 DL* Da* Db* DE*

Untreated 83.4 -0.11 0.46 60.61 0.89

Cationic 10% 83.61 -0.19 1.05 58.01 2.09 0.21 L -0.08 G 0.59 Y 0.63

Cationic 20% 83.05 -0.22 1.12 56.58 2.21 -0.35 D -0.11 G 0.66 Y 0.76

Non-ionic 10% 83.48 -0.14 0.67 59.68 1.32 0.07 L -0.02 G 0.21 Y 0.22

Non-ionic 20% 82.64 -0.11 0.49 58.99 0.96 -0.76 D 0 0.03Y 0.77

Silicon 10% 83.69 -0.13 0.82 59.31 1.65 0.29 L -0.02 G 0.42 Y 0.44

Silicon 20% 83.27 -0.14 0.88 58.21 1.78 -0.13 D -0.02 G 0.42 Y 0.44

Experimental results:

Sample name YI-E313Untreated 0.89

Cationic 10% 2.09Cationic 20% 2.21

Untreated 10 200

0.5

1

1.5

2

2.5

0.89

2.092.21

Cationic softener % ‘vs’ Yellowness index

Cationic softener %

Yel

low

ness

inde

x

Observations:

Untreated Silicon 10% Silicon 20%0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

0.89

1.651.78

Silicon softener % ‘vs’ Yellowness index

Yellowness index

Silicon softener %Ye

llow

ness

inde

x

Sample name YI-E313

Untreated 0.89

Silicon 10% 1.65

Silicon 20%1.78

Untreated Nonionic 10% Nonionic 20%0

0.2

0.4

0.6

0.8

1

1.2

1.4

0.89

1.32

0.96

Non-ionic softener % ‘vs’ Yellowness index

YI-E313

Nonionic softener %Ye

llow

ness

inde

x

Sample name YI-E313

Untreated 0.89

Nonionic 10% 1.32

Nonionic 20% 0.96

Sample name YI-E313

Untreated 0.89

Cationic 10% 2.09

Cationic 20% 2.21

Non-ionic 10% 1.32

Non-ionic 20% 0.96

Silicon 10% 1.65

Silicon 20% 1.78

untreated 10% 20%0

0.5

1

1.5

2

2.5

untreated; 0.89

10%; 2.09 20%; 2.21

untreated; 0.89

10%; 1.6520%; 1.78

10%; 1.32

20%; 0.96

cationic silicon non ionic

Silicon softener %

Yello

wne

ss in

dex

The order of yellowing tendency of softeners- Cationic softener > Silicon softener > Non-ionic softener

Concentration Cationic Silicon Nonionic

Untreated 60.61 60.61 60.61

10% 58.01 59.31 59.68

20% 56.58 58.21 58.99

Untreated 10% 20%54

55

56

57

58

59

60

61Untreated; 60.61

10%; 58.01

20%; 56.58

Untreated; 60.61

10%; 59.31

20%; 58.21

Untreated; 60.6110%; 59.68

20%; 58.99

Whiteness index v/s softner concentration(%)

Cationic silicon Nonionic

Softner conc.(%)W

hite

ness

inde

xThe order of Whitening tendency because of softeners- Cationic softener < Silicon softener < Non-ionic softener

INFERENCES:• Among three kinds of softeners, cationic softener is showing highest

yellowness and least whiteness- Because it’s the only one which is having amine groups.

• On increasing concentration of softener yellowness is increasing in cationic, and silicon softeners but there is no specific trend for non-ionic softener.

• We can’t infer the trend from these three values, So more number of experimental analysis is required.

• Because in cationic softeners quaternary ammonium group may present, hence it’s imparting yellowness to cotton fabric.

AIM-2• To study the softening and yellowing effect of

different cationic softener concentration on cotton fabric.

CATIONIC SOFTENER

RECIPE AND PROCEDURE

RESULT AND DISSCUSSION

• EFFECT ON BENDING LENGTH• EFFECT ON YELLOWNESS• EFFECT ON ABSORBENCY

INFERENCES

AIM-2

To study the softening and yellowing effect of different cationic softener concentration on cotton fabric, by measuring Bending length, absorbency time (Drop test), Whiteness index(CIE WI) and Yellowing Index (YI E313).

CATIONIC SOFTENERDefined as materials which dissolve or disperse in water, concentrate and orient at interfaces and ionize in such a way that the cation includes a hydrocarbon chain, which is hydrophobic and contains from 8 to 25 carbon atoms.

Shows the best soft handle.

Have affinity to almost all fibres and are usually applied by the exhaust method

Only problem is incompatibility with anionic auxiliaries (optical brighteners, dyeing auxiliaries) as well as their tendency to yellow in comparison with non-ionic products.

Cationic softeners are mainly used for coloured textile substrates .

Chemicals Recipe 1 Recipe 2 Recipe 3 Recipe 4

Cationic softener (%)

5 10 15 20

Following tests are done -• Bending length• Absorbency • CIE L a b testingWith change in softener concentration

• Softener Concentration (%) - 5, 10, 15, 20

• M:L - 1:40

• Process- Pad - Dry

RECIPE & PROCEDURE

EFFECT ON BENDING LENGTH

Softener Concentration (%)

Bending Length (cm)Warp Weft

UT 2.75 2.725 2.65 2.3

10 2.55 2.2515 2.35 2.2420 2.23 2.1

RESULT & DISCUSSION:

Control 5 10 15 200

0.5

1

1.5

2

2.5

3 2.75 2.65 2.552.35 2.23

2.72 2.3 2.25 2.24 2.1

Bending length Vs softener conc.

Warp Weft

Softener Concentration (%)

Bend

ing

Leng

th (c

m)

Inference#1• On increasing the softener concentration bending length decreases.Softness inter fibre friction That’s why fibre bends more easily.Inference#2• Warp-way bending length > Weft-way bending length .

May be because • generally EPI >PPI• On warp we applied

size during weaving so residual starch is giving the higher bending length.

For Weftway bending length

For Warpway bending length

EFFECT ON ABSORBENCYSoften

er Conc.

(%)

Absorbency (..m ..sec)

5 4 min10 5min 30 sec15 5 min 55 sec20 9 min

5 10 15 200

100

200

300

400

500

600

240

330 355

540

Abosrbancy time (sec)Abosrbancy (sec)

Softener Conc.(%)

Abso

rben

cy ti

me

(sec

)

On adding cationic softener absorbency reduces drastically-“Because by definition a cationic softener includes a hydrocarbon chain, which is hydrophobic and contains from 8 to 25 carbon atoms.”

For Untreated= 2-3 sec

EFFECT ON YELLOWNESS:1st sample set

Sample name L* a* b* WI-CIE YI-E313 DL* Da* Db* DE*

Untreated 83.25 -0.13 0.48 60.2 0.92        

Cationic 5%(F) 84.04 -0.17 0.57 61.28 1.07 0.79L -0.03G 0.09Y 0.8

Cationic 10%(F) 83.56 -0.18 0.58 60.27 1.09 0.30L -0.05G 0.10Y 0.32

Cationic 15%(F) 84.23 -0.21 0.63 61.35 1.16 0.98L -0.07G 0.15Y 0.99

Cationic 20%(F) 84.1 -0.19 0.71 60.68 1.35 0.85L -0.06G 0.23Y 0.88

Concentration(%) YI-E313-1 Db*-1

0 0.92  

5 1.07 0.09Y

10 1.09 0.10Y

15 1.16 0.15Y

20 1.35 0.23Y

2nd sample set

Sample name L* a* b* WI-CIE YI-E313 DL* Da* Db* DE*

Untreated 83.25 -0.13 0.48 60.2 0.92        

Cationic 5%(B) 83.62 -0.2 0.61 60.27 1.13 0.37L -0.07G 0.13Y 0.4

Cationic 10%(B) 84.1 -0.2 0.63 61.08 1.18 0.85L -0.06G 0.15Y 0.86

Cationic 15%(B) 84.12 -0.19 0.66 60.97 1.25 0.86L -0.05G 0.18Y 0.88

Cationic 20%(B) 84.36 -0.22 0.7 61.27 1.3 1.11L -0.09G 0.22Y 1.14

Concentration(%) YI-E313-2 Db*-2

0 0.92  

5 1.13 0.13Y

10 1.18 0.15Y

15 1.25 0.18Y

20 1.3 0.22Y

Conc. (%)

YI-E313(For 1st

sample set)

YI-E313(For 2nd

sample set)0 0.92 0.92

5 1.07 1.13

10 1.09 1.18

15 1.16 1.25

20 1.35 1.30 5 10 15 20

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

0; 0.92

5; 1.0710; 1.09

15; 1.16

20; 1.35

0; 0.92

5; 1.1310; 1.18

15; 1.25

20; 1.3

YI-E313-1 YI-E313-2

Cationic softener Concentration (%)

Yello

wne

ss in

dex

YI-E

313

Concentration(%)

Db* (For 1st sample set)

Db* (For 2nd sample set)

5 0.09Y 0.13Y

10 0.10Y 0.15Y

15 0.15Y 0.18Y

20 0.23Y 0.22Y

5 10 15 200

0.05

0.1

0.15

0.2

0.25

5; 0.09 10; 0.1

15; 0.15

20; 0.23

5; 0.13

10; 0.15 15; 0.1820; 0.22

Db* value v/s Concentration(%)

Db* (For 1st sample set) Db* (For 2nd sample set)

Concentration(%)

Db*

valu

e

Conclusion: Among all type of softeners cationic softeners are showing the more yellowing for cotton

fabric.

Higher the concentration of cationic softener, more will be the –• Yellowing effect• Softening effect• And lesser absorbency.

For minimizing the yellowness of cotton we will prefer lesser concentration of softener.

REFERENCES:• Handbook of fiber science and technology. Vol. II; Functional finishes: Part B. Menachem Lewin und

Stephen B. Sello.• GUPTA, D. "Softening treatments for technical textiles." Advances in the Dyeing and Finishing of Technical

Textiles (2013): 154.• Boethling, R. S., Elizabeth Sommer, and David DiFiore. "Designing small molecules for

biodegradability." Chemical reviews 107, no. 6 (2007): 2207-2227.• Bakhtyar, S.; Nguyen, K.; Rabke, S.; Gagnon, M. M. Closed Bottle Biodegradation Test for Drilling Fluids.

Presented at the 27th Annual Meeting, Society of Environmental Toxicology and Chemistry (SETAC) North America, Montreal, Canada, 5-9 Nov, 2006. 

• Ajayi, Joseph O. "Fabric smoothness, friction, and handle." Textile research journal 62, no. 1 (1992): 52-59.• Ali, S. I., and Shahida Begum. "Fabric softeners and softness perception."Ergonomics 37, no. 5 (1994): 801-

806.• Czech, A. M., J. Pavlenyi, and A. J. Sabia. "Modified Silicone Softeners for Fluorocarbon Soil Release

Treatments." Textile Chemist & Colorist 29, no. 9 (1997).• Almeida, Luís de, and Artur Cavaco Paulo. "Softening of cotton by enzymatic hydrolysis." (1993).

Thank you…