Retro engineering approach for

consumer-based quality calculation

08/11/2018

Author : Romain BENKIRANE

Co-authors : Sébastien THOMASSEY

Co-authors : Ludovic KOEHL

Co-authors : Anne PERWUELZ

Funding : Région Hauts-de-France, ECO TLC

Overview

❖ Context

❖ Objectives

❖ Application on T-shirts

❖ Characterization & testing

❖ Yarn Characterization

❖ Fabric Characterization

❖ Performances tests & Results

❖ Consumer-based quality calculation

❖ Quality main contributors

❖ Limits and perspectives

❖ Conclusion

Context

2

Lifetime

ConsumerInherent

quality

Use phase Sensitivity to

tear of clothing

Raw

material Process

Environmental impact

LCA

Assumptions

Envionmental

labelling

Recycling fee

adjustment

Avnir 2017

Objectives

Current proposal (ADEME):

❖ Useful life (not measurable)

❖ Normative lifetime (measurable) = average lifetime measured in specifics tests

conditions

Our proposal:

❖ Evaluation of lifetime (as close as possible to useful life)

❖ Calculation of the consumer-based Quality (CQ)

𝐶𝑄 = 𝑓 𝑐𝑙𝑜𝑡ℎ𝑒, 𝑐𝑜𝑛𝑠𝑢𝑚𝑒𝑟

3

Methodology

4

Co

nsu

mer

s Survey

End of

Life

Decision

-support

system

…

…

…

…

…

…

…

…

…

…

…

…

Consume

r-based

Quality

Lifetime

Consumer

sensitivity to wear

and tear of clothing

Possible end of life

causes / product

Standards

tests

Tests

results

Structure

31 T-shirts tested

Source : national & international textile retailers

Application on Tshirts

5

31 Tshirts

26« casual »

5« Sports »

17Cotton

6Polyester

5Flax

3Blend

13

Black

3

White

5Grey

7

Dark blue

1

Beige

2

Red

Characterization & testing

6

Structure

Characterization« Performances »

Loss of colour

Loss of shape

Opened / Torn seam

Hole(s)

Pilling

Yarn Fabric

Count

Twist

Tenacity

Process

Construction

Yarn consumption

Thickness

Area density

Seam …

31 T-shirts tested

Source : national & international retailers textile

Yarn characterization

7

Yarn

Process

Ring Spinning

Wet Spinning

Rotor

MTFT

Count

(Nm)

[24 ; 85]

Twist level

Twist/m

[430 ; 950]

TenacitycN/Tex

[0,30 ; 22]

Fabric characterization

8

Fabric

Process

Weft knitting

Warp knitting

Construction

Jersey

Ribs 1*1

Thickness(mm)

[0,4 ; 0,8]

Area density(g/m²)

[115 ; 230]

Nb of Stitches / inch

[3 ; 6]

Performances tests results

9

Min Max

Colour Colour Fastness

Light -

Washing 2 5

Water 3 5

Perspiration -

Ironing (4h) 4,5 5

Rubbing dry 3,5 5

Rubbing wet 2,5 5

Shape

Dimensional stability (%)

10 wash

Column -15 3

Row -6 8

Spirality (%) 10 wash 0,5 15

Appearance -

Elasticity -

All tests have been led at Gemtex Laboratory according to ISO standards

Performances tests results

10

Min Max

Seam Seam tensile properties (N)Column 70 250

Row 50 270

Hole(s)

Bursting In progress

Fraying resistance In progress

Abrasion resistance

(martindale)In progress

Pilling

PillingBox (14000 cycles)Mass loss (%) 0 3

Gradation (/5) 3 5

Martindale (8000 cycles)Mass loss (%) -1,5 16

Gradation (/5) 1,5 5

All tests have been led at Gemtex Laboratory according to ISO standards

Consumer-based quality calculation

11

Consumer

-based

Quality

α Colour

α Shape

α Seam

α Hole(s)

α Pilling

Consumer sensitivity

to wear and tear of

clothing

Average colour results

Average shape results

Average seam results

Average hole(s) results

Average pilling results

Tests

results

Consumer sensitivity

12

Co

nsu

mer

s Survey

End of

Life

Decision

-support

system

…

…

…

…

…

…

Consumer sensitivity

to wear and tear of

clothing

Possible end of life

causes / product

850

survey

responses

Fuzzy

AHP

α Colour

15%

α Pilling

14%

α Shape

26%

α Seam

18%

α Hole(s)

27%

0,00

0,10

0,20

0,30

0,40

0,50

0,60

0,70

0,80

0,90

1,00T

S12

TS

14

TS

24

TS

28

TS

6

TS

7

TS

26

TS

25

TS

1

TS

27

TS

4

TS

10

TS

8

TS

5

TS

13

TS

30

TS

9

TS

21

TS

16

TS

29

TS

17

TS

3

TS

11

TS

22

TS

23

TS

20

TS

15

TS

2

TS

18

TS

19

TS

31

Consumer-based quality score

Tshirts comparison

Consumer-based quality score

13

! Hole(s) ( = 27% consumer sensitivity) are not taken into account yet

Bet

ter

Qual

ity

Consumer-based quality calculation

14

Consumer-

based

Quality

α Colour

α Shape

α Seam

α Hole(s)

α Pilling

Consumer sensitivity

to wear and tear of

clothing

Average colour results

Average shape results

Average seam results

Average hole(s) results

Average pilling results

Tests

results

Yarn & Fabric

Characteristics

Quality

contributors

Use of Principal component Analysis (PCA) - Analysis for 24 Tshirts

Results are exclusively valid for studied Tshirts

Quality contributors

15

Higher Quality Score

=

Thiner yarn

High nb of stitches/inch

Lower thickness & area

density

! Hole(s) are not taken

into account yet

Use of Principal component Analysis (PCA) - Analysis for Coton Tshirts (17)

Results are exclusively valid for studied Tshirts

Quality contributors

16

Higher Quality Score

=

High yarn tenacity

High nb of stitches

! Hole(s) are not taken

into account yet

Limits

❖ ~ 30 T-shirts tested➔ representativeness (material, process)

❖ Is there a need of a standard Tshirt with a standardized lifetime ?

Perspectives

❖ Short & mid term

❖ Evaluate lifetime through repeated washing cycles (in progress)

❖ Model a consumer-based quality / lifetime relation to predict lifetime

❖ Incorporate into LCA assumptions

❖ Long term

❖ Improve the methodology

❖ Wider consumer focus (fashion, emotionnal attachment, physiological tests)

Limits & perspectives

17

❖ Methodology to evaluate the lifetime

❖ Based on the consumer-based quality

❖ Depend on the manufacturing process and on the consumer

❖ Better evaluation of the lifetime to reduce the LCA assumptions

❖ Highlight of ecodesign strategies through retro engineering approach

❖ Quality contributors using the Tshirts characteristics and the calculated quality

score and data mining technique (PCA)

Conclusion

18

Thanks for your attention

Any questions ?

19