j.m. lucas, r.a.l. miguel, p.t. fiadeiro, m.j.s. silva, m.l.a.g. carvalho [email protected] university...
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J.M. Lucas, R.A.L. Miguel, P.T. Fiadeiro, M.J.S. Silva, M.L.A.G. Carvalho
University of Beira Interior
R&D Unit of Textile and Paper Materials – Dep. of Textiles
Covilhã - PORTUGAL
Innovative Optical Device for Gloss Evaluation of Worn Garments
17th IMACS World CongressScientific Computation, Applied Mathematics and Simulation
Paris, France July 11 - 15, 2005
J. M. Lucas University of Beira Interior - PORTUGAL
Innovative Optical Device for Gloss Evaluation of Worn Garments
The abrasion resistance is one of the most important properties of garment fabrics.
During wear, clothes are permanently subjected to friction, either between them or against common objects.
Abrasion usually causes:
Introduction
loss of weight
yarn breakage
change of colour
pilling formation
gloss
J. M. Lucas University of Beira Interior - PORTUGAL
Innovative Optical Device for Gloss Evaluation of Worn Garments
Introduction
One of the main reasons to reject a worsted fabric is due to the level of gloss caused by wear, this being possible without having a significant weight loss.
Rejection point of a garment:
Excessive surface gloss
Small physical fibre degradation
J. M. Lucas University of Beira Interior - PORTUGAL
Innovative Optical Device for Gloss Evaluation of Worn Garments
Given the multiplicity of parameters that influence the abrasion procedure and the difficulty to quantify the fabric abrasion resistance, no analytic method is yet available which is accepted without constrains by the different textile organisations.
The classical methods to evaluate abrasion resistance do not include the assessment of gloss.
Introduction
J. M. Lucas University of Beira Interior - PORTUGAL
Innovative Optical Device for Gloss Evaluation of Worn Garments
Testing methods based on the Martindale Wear & Abrasion Tester simulate abrasion undergone by fabrics during wear, the test being carried out up to the breakage of two yarns in the specimens subjected to friction.
This is an objective method that does not translate the useful life of fabrics, since well before the physical degradation takes place, fabrics may already have lost wear properties due to the change of their surface appearance. I
ntroduction
J. M. Lucas University of Beira Interior - PORTUGAL
Innovative Optical Device for Gloss Evaluation of Worn Garments
The testing methodology simulates the abrasion of fabrics against frequent contact materials which enable gloss formation.
The Martindale abrasion procedure was changed, the standard abrasion fabric being substituted by a common material that easily allows an increase of gloss.
All fabrics tested were subjected to a given set of abrasion stages.
Introduction
J. M. Lucas University of Beira Interior - PORTUGAL
Innovative Optical Device for Gloss Evaluation of Worn Garments
Optimistic results have been achieved using three different techniques:
Measurement of colour parameters using spectrophotometer, the evaluation of gloss being made using luminance and total colour difference;
Assessment of lightness of abraded samples using an image analysis system;
Measurement of gloss using an optical set up using a collimated laser beam.
Introduction
J. M. Lucas University of Beira Interior - PORTUGAL
Innovative Optical Device for Gloss Evaluation of Worn Garments
Establishment of a gloss measuring quality control method to evaluate loss of appearance of fabrics subjected to abrasion.
Establishment of a scientific and technological basis to develop an apparatus for the evaluation of gloss on worn garments. Introduction
Objectives
J. M. Lucas University of Beira Interior - PORTUGAL
Innovative Optical Device for Gloss Evaluation of Worn Garments
Materials and Methods 10 fabrics
100% wool10 fabrics
polyester/wool
Gloss formation of fabrics
Woolmark Company IWS TM112 test
method
Behaviour
Recommendations
Useful life Limit
20000 abrasion cycles
Abrasion Stages
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15000
20000
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15000
20000
J. M. Lucas University of Beira Interior - PORTUGAL
Innovative Optical Device for Gloss Evaluation of Worn Garments
Materials and Methods
1000
5000
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15000
20000
Image Analysis System
All fabrics
100
200
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1000
1500
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10000
15000
20000
Laser Setup
2 WO
2 PES/WO
fabrics
Panel of Users:
Wear Limit
J. M. Lucas University of Beira Interior - PORTUGAL
Innovative Optical Device for Gloss Evaluation of Worn Garments
Results and Discussion
Recent work
In the most recent works, the Differential Gloss Gradient (DGG) at 20000 cycles was evaluated for each fabric.
On the basis of a 0 to 10 scale, the user’s panel classified fabrics concerning the amount of gloss formed.
0123456789
10
Same appearance as original fabric
Highest amount of gloss
J. M. Lucas University of Beira Interior - PORTUGAL
Innovative Optical Device for Gloss Evaluation of Worn Garments
Results and Discussion
Recent work
The correlation between the objective evaluation (image analysis system) and the subjective one (user’s panel) has regression coefficient R2 of 73%.
From this value it may be considered quite promising to consider a valid objective method, considering the experience of the user’s panel.
J. M. Lucas University of Beira Interior - PORTUGAL
Innovative Optical Device for Gloss Evaluation of Worn Garments
Results and Discussion
Recent work
Wool Fabrics Polyester/Wool Fabrics
Fabric DGG(20000 cycles)
User´s Panel Evaluation
Fabric DGG(20000 cycles)
User´s Panel Evaluation
LAL1 35 4 PLL1 3,6 3
LAL2 53,8 1 PLL2 37,7 7
LAL3 98,5 7 PLL3 17,4 8
LAL4 70,3 8 PLL4 58,5 10
LAL5 14,4 1 PLL5 8,5 1
LAL6 33,4 5 PLL6 24,2 7
LAL7 4,6 1 PLL7 43,7 7
LAL8 159,6 10 PLL8 13,8 5
LAL9 57,5 5 PLL9 3,5 1
LAL10 29,3 3 PLL10 42,3 8
Regression CoeficienR2 = 73%
Regression CoeficienR2 = 71%
CORRELATION BETWEEN OBJECTIVE AND SUBJECTIVE GLOSS EVALUATION FOR WOOL AND POLYESTER/WOOL FABRICS
J. M. Lucas University of Beira Interior - PORTUGAL
Innovative Optical Device for Gloss Evaluation of Worn Garments
Conclusions
The low correlation values (1) have been achieved for fabrics which present at least one of the following characteristics:
- Polyester fibres in its composition;
- Blend effects with a marked contrast;
- Yarn unevenness when warp and weft have different colours.
For fabrics having these characteristics, the followed method is not the most suitable to evaluate gloss formation.
J. M. Lucas University of Beira Interior - PORTUGAL
Innovative Optical Device for Gloss Evaluation of Worn Garments
Conclusions
Comparing the obtained results by both methods to evaluate the gloss formation in fabrics, it can be said that the R2 values for regressions between DGG and the abrasion stages are of the same order for 100% wool fabrics.
In polyester/wool fabrics the R2 values between the abrasion stages and DGG obtained using the optical laser set up seem to be much better than those used the other measuring technique.
J. M. Lucas University of Beira Interior - PORTUGAL
Innovative Optical Device for Gloss Evaluation of Worn Garments
Conclusions
Based on the experience, the user’s panel may define, as a function of the fabric end use, a limit value on the subjective scale.
This value represents the point from which the fabric is no longer suitable for use, due to the high amount of gloss. Through the regression curve, the limit DGG can be found.
J. M. Lucas University of Beira Interior - PORTUGAL
Innovative Optical Device for Gloss Evaluation of Worn Garments
Conclusions
Thus, conditions are met to establish a new objective method of quality control concerning the tendency of fabrics to form gloss and, thus, to evaluate the useful life respecting to this characteristic.
For this, it is enough to submit the fabric to the abrasion process in the Martindale apparatus, using a proper abrasion surface during 20000 cycles.
After, the amount of gloss should be measured in both fabric samples, before and after abrasion using the image analysis system, and then calculate the DGG of fabric and compare it with limit DGG defined by the user’s panel.
Innovative Optical Device for Gloss Evaluation of Worn Garments
J.M. Lucas, R.A.L. Miguel, P.T. Fiadeiro, M.J.S. Silva, M.L.A.G. Carvalho
University of Beira Interior
R&D Unit of Textile and Paper Materials – Dep. of Textiles
Covilhã - PORTUGAL
J. M. Lucas University of Beira Interior - PORTUGAL
Innovative Optical Device for Gloss Evaluation of Worn Garments
100% wool fabrics
Characteristics of fabrics studied
Fabric Weight
(gr/m2)
Weave Kind of Finish
Colour Effect
LAL1 174 Plain Clear Single colour
LAL2 184 Plain Clear Blend
LAL3 146 Plain Clear Blend
LAL4 174 Plain Clear Single colour
LAL5 203 Twill 3 Soft Milled Blend
LAL6 147 Plain Clear Different colours of warp
and weft
LAL7 181 Twill 3 Soft Milled Blend
LAL8 174 Twill 3 Clear Single colour
LAL9 161 Twill 2/2 Clear Blend
LAL10 225 Fantasy Clear Single colour
Fabric Weight
(gr/m2)
Weave Kind of Finish
Colour Effect
PLL1 243 Twill 3 Clear Single colour
PLL2 188 Fantasy Clear Single colour
PLL3 161 Plain Clear Single colour
PLL4 177 Fantasy Clear Different colours of warp
and weft
PLL5 177 Plain Clear Blend
PLL6 218 Twill 2/2 Clear Single colour
PLL7 176 Plain Clear Single colour
PLL8 196 Fantasy Clear Single colour
PLL9 184 Plain Clear Blend
PLL10 224 Plain Clear Single colour
polyester/ wool fabrics
J. M. Lucas University of Beira Interior - PORTUGAL
Innovative Optical Device for Gloss Evaluation of Worn Garments
Differential Gloss Gradient values for each abrasion stage of 100% wool fabrics, using the image analysis
system
Results and Discussion
Previous work
0,0
20,0
40,0
60,0
80,0
100,0
120,0
140,0
160,0
180,0
1000 5000 10000 15000 20000
Abrasion Stage (cycles)
Dif
fere
nti
al G
los
s G
rad
ien
t (%
)
LAL1 LAL2 LAL3 LAL4 LAL5 LAL6 LAL7 LAL8 LAL9 LAL10
J. M. Lucas University of Beira Interior - PORTUGAL
Innovative Optical Device for Gloss Evaluation of Worn Garments
0,0
10,0
20,0
30,0
40,0
50,0
60,0
70,0
1000 5000 10000 15000 20000
Abrasion Stage (cycles)
Diff
eren
tial G
loss
Gra
dien
t (%
)
PLL1 PLL2 PLL3 PLL4 PLL5 PLL6 PLL7 PLL8 PLL9 PLL10
Differential Gloss Gradient values for each abrasion stage of polyester/wool fabrics, using the image
analysis system
Results and Discussion
Previous work
J. M. Lucas University of Beira Interior - PORTUGAL
Innovative Optical Device for Gloss Evaluation of Worn Garments
Number of limit abrasion cycles for a limit DGG (wool fabrics).
Fabric Image Analysis System
R2 (%) Number of limit cycles
LAL1 91.26 67784
LAL2 91.40 17713
LAL3 98.97 13046
LAL4 99.25 12324
LAL5 94.27 (3)
LAL6 78.74 (1)
LAL7 93.72 78543
LAL8 98.41 8448
LAL9 98.94 15001
LAL10 95.71 26449
Number of limit abrasion cycles for a limit DGG (polyester/wool fabrics).
Fabric Image Analysis System
R2 (%) Number of limit cycles
PLL1 11.84 (1)
PLL2 89.88 20239
PLL3 96.80 (2)
PLL4 97.66 12270
PLL5 98.44 102390
PLL6 60.16 (1)
PLL7 99.82 16713
PLL8 73.70 (1)
PLL9 5.07 (1)
PLL10 99.91 18402
Relationship between differential gloss gradient and number of abrasion cycles
(1) Low correlation values
(2) Light colour fabric
(3) Surface pile fabric
Results and Discussion
Previous work
J. M. Lucas University of Beira Interior - PORTUGAL
Innovative Optical Device for Gloss Evaluation of Worn Garments
Differential Gloss Gradient values for each abrasion stage of 100% wool and polyester/wool fabrics,
using the optical laser set up
Results and Discussion
Previous work
-50
0
50
100
150
200
250
300
100 200 400 600 1000 1500 2000 3000 5000 10000 15000 20000
Abrasion Stage (cycles)
Dif
fere
nti
al
Glo
ss
Gra
die
nt
(%)
LAL1 LAL4 LAL8 LAL9
J. M. Lucas University of Beira Interior - PORTUGAL
Innovative Optical Device for Gloss Evaluation of Worn Garments
UNIVERSITY OF BEIRA INTERIOR UNIVERSITY OF BEIRA INTERIOR R&D Unit of Textile and Paper Materials – R&D Unit of Textile and Paper Materials –
Textile DepartmentTextile Department
1717thth IMACS WORLD CONGRESS SCIENTIFIC IMACS WORLD CONGRESS SCIENTIFIC COMPUTATION, APPLIED MATHEMATICS AND COMPUTATION, APPLIED MATHEMATICS AND
SIMULATIONSIMULATION
Paris, France July 11-15, 2005Paris, France July 11-15, 2005
A NEW EQUIPMENT FOR PILLING EVALUATION ON A NEW EQUIPMENT FOR PILLING EVALUATION ON WOOL FABRICS BASED ON OPTICAL ANALYSISWOOL FABRICS BASED ON OPTICAL ANALYSIS
M.L.Carvalho, R.A.L.Miguel, J.M.Lucas, P.T.Fiadeiro, M.J.S. Silva
Pilling formationPilling formation
Is the result of abrasion fabric that mostly affects its surface appearance.
Is the consequence of abrasion of garments, either between them, or against common objects of day life.
UNIVERSITY OF BEIRA INTERIOR UNIVERSITY OF BEIRA INTERIOR R&D Unit of Textile and Paper Materials – R&D Unit of Textile and Paper Materials –
Textile DepartmentTextile Department
UNIVERSITY OF BEIRA INTERIOR UNIVERSITY OF BEIRA INTERIOR R&D Unit of Textile and Paper Materials – R&D Unit of Textile and Paper Materials –
Textile Department Textile Department
PillingPilling is the formation of fuzzy balls on the surface of a fabric.
PillingPilling occurs when loose fibres in the fabric are worked to the surface after the fabric is subjected to abrasion.
PillingPilling phenomenonphenomenon is highly revealed on fabrics made of synthetics fibres.
UNIVERSITY OF BEIRA INTERIOR UNIVERSITY OF BEIRA INTERIOR R&D Unit of Textile and Paper Materials – R&D Unit of Textile and Paper Materials –
Textile Department Textile Department
Evaluation of fabric ability for pilling formation:Evaluation of fabric ability for pilling formation:
Comparison of fabric appearance with photographic standards;Counting or weighting the neps on a given surface area of the fabric;Image analysis techniques;Laser triangulation techniques.
The accuracy of the results not The accuracy of the results not always is the best onealways is the best one
UNIVERSITY OF BEIRA INTERIOR UNIVERSITY OF BEIRA INTERIOR R&D Unit of Textile and Paper Materials – R&D Unit of Textile and Paper Materials –
Textile Department Textile Department
EVALUATIONEVALUATIONThe comparison of the abraded fabric appearance with photographic standards is the most current evaluation method for pilling formation, but this method is highly subjective, and the photographic standard cannot represent all the kind of fabrics.
For this reason, it becomes important the definition of an objective method to evaluate pilling formation.
UNIVERSITY OF BEIRA INTERIOR UNIVERSITY OF BEIRA INTERIOR R&D Unit of Textile and Paper Materials – R&D Unit of Textile and Paper Materials –
Textile Department Textile Department
EVALUATIONEVALUATION In this study, we propose a method for pilling evaluation, objective,, objective, based on the optical profile analysis, using a collimated light beam. The optical profiles are measured using a CCD detector along fabric sample, the untreated one and those subjected to pilling.
The pilling simulation was made using Martindale Wear & Abrasion Tester, according to Woolmark TM 196 (2000) Test method.
UNIVERSITY OF BEIRA INTERIOR UNIVERSITY OF BEIRA INTERIOR R&D Unit of Textile and Paper Materials – R&D Unit of Textile and Paper Materials –
Textile Department Textile Department
Optical profile analysisOptical profile analysis
The proposed method is based on the shade generated by the pilling developed along the sample optical profile..
Original sample Sample with pilling
UNIVERSITY OF BEIRA INTERIOR UNIVERSITY OF BEIRA INTERIOR R&D Unit of Textile and Paper Materials – R&D Unit of Textile and Paper Materials –
Textile Department Textile Department
Experimental mountingExperimental mounting
UNIVERSITY OF BEIRA INTERIOR UNIVERSITY OF BEIRA INTERIOR R&D Unit of Textile and Paper Materials – R&D Unit of Textile and Paper Materials –
Textile Department Textile Department
It is possible to quantify the variation of the illuminated area L
L = Lp – LaL = Lp – La
Lp- illuminated area of original sample
La- illuminated area of the sample subjected to abrasion
Pilling Index IP:Pilling Index IP:
IP = IP = ( (L / Lp)x100L / Lp)x100
UNIVERSITY OF BEIRA INTERIOR UNIVERSITY OF BEIRA INTERIOR R&D Unit of Textile and Paper Materials – R&D Unit of Textile and Paper Materials –
Textile Department Textile Department
RESULTS AND DISCUSSIONRESULTS AND DISCUSSION
The variation of the illuminates area L increases with the amount of pilling formed.
Pilling Degree PD
Standard illuminated area
Lp
Sample illuminated area after abrasion
La
Difference of illuminated area
L
Pilling Index IP
1
1-2
2
2-3
3
3-5
4
4-5
5
98.624
97.997
97.951
98.887
99.071
99.048
99.077
99.049
99.326
94.644
94.756
95.049
97.129
97.758
97.657
98.616
98.445
99.300
3.977
3.241
2.902
1.758
1.313
1.391
0.461
0.634
0.026
4.033
3.308
2.963
1.778
1.32 5
1.404
0.465
0.640
0.026
UNIVERSITY OF BEIRA INTERIOR UNIVERSITY OF BEIRA INTERIOR R&D Unit of Textile and Paper Materials – R&D Unit of Textile and Paper Materials –
Textile Department Textile Department
Relationship between the conventional degree of pilling PD and the pilling index IP (average values)
-1
0
1
2
3
4
5
1 1.5 2 2.5 3 3.5 4 4.5 5
Pilling Degree PD
Pill
ing
Inde
x IP
1,5 corresponds to 1-2 degree 2,5 corresponds to 2-3 degree3,5 corresponds to 3-4 degree 4,5 corresponds to 4-5 degree
UNIVERSITY OF BEIRA INTERIOR UNIVERSITY OF BEIRA INTERIOR R&D Unit of Textile and Paper Materials – R&D Unit of Textile and Paper Materials –
Textile Department Textile Department
Relationship between the conventional degree of pilling DP and the pilling index IP
(measured values)
1,5 corresponds to 1-2 degree 2,5 corresponds to 2-3 degree3,5 corresponds to 3-4 degree 4,5 corresponds to 4-5 degree
UNIVERSITY OF BEIRA INTERIOR UNIVERSITY OF BEIRA INTERIOR R&D Unit of Textile and Paper Materials – R&D Unit of Textile and Paper Materials –
Textile Department Textile Department
RESULTS AND DISCUSSIONRESULTS AND DISCUSSION
The correlation between objective evaluation of pilling formation, given by IP (Pilling Index) and the subjective evaluation of the same property based
on photographic scale of standard PD (Pilling Degree) is given by the following mathematics
equation:
IP = 4.75 – 0.96 PDIP = 4.75 – 0.96 PD
This equation has an interesting correlation coefficient R2 of 89.8%
UNIVERSITY OF BEIRA INTERIOR UNIVERSITY OF BEIRA INTERIOR R&D Unit of Textile and Paper Materials – R&D Unit of Textile and Paper Materials –
Textile Department Textile Department
CONCLUSIONSCONCLUSIONS
The existing methods to evaluate pilling formation are visual and thus subjective.
The proposed method allows an objective evaluation of this characteristic. It is based on the relationship between the illuminated area of the optical profiles of fabric with pilling and of original sample (standard). The variation of illuminated area relates directly to the pilling index IP.
UNIVERSITY OF BEIRA INTERIOR UNIVERSITY OF BEIRA INTERIOR R&D Unit of Textile and Paper Materials – R&D Unit of Textile and Paper Materials –
Textile Department Textile Department
CONCLUSIONSCONCLUSIONS
The next steps will comprise the definition of an equation that better correlates the pilling index IP and the degree of pilling determined by the subjective evaluation.
Using a properly designed computer application, the optical system for pilling formation evaluation may convert the optical reading to pilling degree well known in the textile area.
UNIVERSITY OF BEIRA INTERIOR UNIVERSITY OF BEIRA INTERIOR R&D Unit of Textile and Paper Materials – R&D Unit of Textile and Paper Materials –
Textile Department Textile Department
CONCLUSIONSCONCLUSIONS
The correlation found has an R2 of 89.9%, this value being quite hopeful to keep increasing the number of tests, in order to achieve a more accurate tendency of the relationship between objective and subjective evaluations.