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The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
Cleveland,Ohio
Headquarters &
Instrument Division
Bolton, England
Q-Lab Europe
Founded in 1956
Specialize in material durability testing equipment
and services
Shanghai, China
Q-Lab China
Saarbrücken Germany
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
Miami, Florida Phoenix, AZ
Q-Lab Weathering Research Services
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
Case Study
Large manufacturer of full product line of pressure sensitive tapes
Concerned about degradation of adhesive, backing, and, in some products, color
Various adhesive chemistries
Tests both outdoor “durable” and general use tapes
Testing is performed for R&D
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
Know Your Enemy
Sunlight
Temperature
Moisture
Other factors
Irradiance:
The rate at which light energy falls on a
surface, per unit area; W/m2
ASTM G113 -Terminology
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
Summer Sunlight Standard
250 350 450 550 650
0.0
0.5
1.0
1.5
2.0
Wav elength (nanometers)
Irra
dia
nc
e
W/m
2/n
m
Visible LightUV Region
UV
-A
UV
-B
UV
-C
0.68 W/m2 at 340 nm
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
Short Wavelengths - Polymer
Degradation
Long Wavelengths - Fading &
Color Change
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
Seasonal Variation
Intensity changes 8:1 @ 320 nm
Cut-off shifts from 295 to 310 nm
Summer
Winter
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
Thermal Cycling Effects
Physical stress
Coatings on plastics
Assemblies
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
Q-Lab’s TOW Research
Things Are Wet Outdoors Longer Than You Think
Don’t Underestimate the Effect
of Moisture
Changes The Rate
Changes Mode Of Degradation
Difficult To Accelerate
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
Exposure Locations
Florida subtropical
Arizona desert sunshine
Others
(www.q-lab.com for climate data)
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
0
2
4
6
8
10
12
250 350 450 550 650 750
Wavelength (nm)
Irra
dia
nce
(W
/m²/
nm
)
Summer Sunlight
Q-Trac
Summer Sunlight vs. Q-Trac
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
Outdoor Techniques Offer The Closest
Simulation to Your Service Environment
But remember:
Weather varies greatly
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
Xenon Arc Spectra
filtering
irradiance level
control point
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
SPD's of Q-Sun and UVA-340 Lamps vs. Sunlight
0.0
0.5
1.0
1.5
2.0
2.5
3.0
250 300 350 400 450 500 550 600 650 700 750 800
Wavelength (nm)
Irra
dia
nc
e (
W/m
²/n
m)
Xenon With Daylight Filters
Sunlight
Xenon with
Daylight Filters
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
0.0
0.2
0.4
0.6
0.8
1.0
1.2
260 280 300 320 340 360 380 400
Wavelength (nm)
Irra
dia
nc
e (
W/m
²/n
m)
Xenon with Daylight Filters
Xenon with
Daylight Filters
Sunlight
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
0.0
0.5
1.0
1.5
2.0
2.5
3.0
250 300 350 400 450 500 550 600 650 700 750 800
Wavelength (nm)
Irra
dia
nc
e (
W/m
²/n
m)
Xenon with Window Glass Filters
Xenon with Window
Glass Filters
Sunlight
Through
Window Glass
Sunlight
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
0.0
0.2
0.4
0.6
0.8
1.0
1.2
260 280 300 320 340 360 380 400
Wavelength (nm)
Irra
dia
nc
e (
W/m
²/n
m)
Xenon with Window Glass Filters
SunlightSunlight Through
Window Glass
Xenon with
Window
Glass Filters
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
Xenon Arc Summary
full spectrum - UV, Visible, IR
best simulation of long wave
UV & visible
calibration
water spray
relative humidity control
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
UV Fluorescent
Weathering
TesterIntroduced 1970
model QUV/spray
ASTM G154
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
0.0
0.2
0.4
0.6
0.8
1.0
1.2
270 290 310 330 350 370 390
Wavelength (nm)
Irra
dia
nc
e W
/m²/
nm
UV-B Lamps
FS-40 Lamps
UVB-313 Lamps
Sunlight
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
UVA-340 Lamps
0.0
0.2
0.4
0.6
0.8
1.0
1.2
260 280 300 320 340 360 380 400
Wavelength (nm)
Irra
dia
nc
e (
W/m
²/n
m)
Sunlight
air mass=1.0
(CIE 85 table 4)
QUV with UVA-340 lamps
0.68 W/m2 @ 340 nm
UVB-313 Lamps QUV/se
0.0
0.2
0.4
0.6
260 280 300 320 340 360 380 400
Wavelength (nm)
Irra
dia
nce (
W/m
²/n
m) 5,600-hour lamps
2-hour lamps
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
0.0
0.5
1.0
1.5
270 290 310 330 350 370 390
Wavelength (nm)
Irra
dia
nce
(W
/m²/
nm
)
Effect of Intensity UVA-340
Intensified 75%
Typical Intensity
Sunlight
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
Fluorescent Lamp Advantages
fast results
very stable spectrum
minimal maintenance
simple calibration
low cost
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
QUV Moisture
condensing humidity
water spray
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
Condensation Advantages
identical to natural wetness
elevated temperature
pure water
easy to use
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
QUV vs. Q-Sun
UVA-340 best simulation
of shortwave UV
UVB-313 might be too severe
no visible light
stable spectrum
irradiance control
no RH control
water spray or condensation
full spectrum
best simulation of long wave
UV & visible light
spectrum changes
irradiance control
relative humidity control
water spray
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
QUV, Xenon, Sunlight...
0.0
0.5
1.0
1.5
2.0
2.5
3.0
250 300 350 400 450 500 550 600 650 700 750 800
Wavelength (nm)
Irra
dia
nc
e (
W/m
²/n
m)
Q-Sun with Daylight Filters0.68 W/m2 @ 340 nm
Sunlightair mass=1.0 (CIE 85 table 4)
QUV with UVA-340 lamps0.68 W/m2 @ 340 nm
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
Xenon arc is Best For Testing
Lightfastness / Color
Degradation
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
QUV Is The Best For Polymer
Degradation
gloss loss
yellowing
chalking
checking
adhesion
cracking
tensile
strength
loss
Impact
resistance
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
UVA-340 Is the Best Available
Simulation of Short-Wave UV
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
Case Study
QUV
Tests adhesive and also the backing facing the light
Uses 12” x 9” glass substrates
5 pull-downs per specimen
1 pull down per time interval
Generates time degradation curves
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
Case Study
QUV material failure modes
Adhesive residue left on glass
Tape locks down on glass, falls apart when removed
QUV Test Cycles
72 to 96 hours is usually enough to tell a good material from a bad one
Uses various custom cycles
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
Case Study
Q-Sun Xenon Test Chamber
Used when color is a concern, usually for duct
tapes
Sometimes used to test adhesives of less durable
materials; similar results to QUV
Results typically take longer than QUV for
adhesive and backing tests
Custom cycles, plus ASTM D6551
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
Case Study-- Conclusions
Results are comparative
Degradation modes are correlated to
outdoor testing
Acceleration factors are not considered
accurate “because weather varies so
much”
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
Case Study-- Conclusions
Benefits of Test Program
Data is used to make good decisions
Materials
Processes
Question: any stories to tell about product
failures or catastrophes avoided?
“We haven’t had any as far as I know.”
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
Case Study – Lessons Learned
Define modes of degradation and test for each (color change, adhesive degradation, backing degradation)
Define failure end-point
UV fluorescent and xenon each have strengths
Comparisons using rank order are very powerful!
Must use outdoor testing to validate lab results
Faster than you think!
Inexpensive!
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
Case Study – Opportunities
Use control specimens
Use a well-understood good performer
Learn from failures, retain a well-
understood poor performer
Develop time degradation curves for each
control
Laboratory AND outdoor
The Most Trusted Name In Weathering
© 2007 Q-Lab Corporation
Ideal Test Program
Outdoor weathering in FL, AZ, or both
Real world data
Correlation
Accelerated weathering in UV fluorescent, Xenon, or Fresnel
Concentrator or a combination
Fast results
Formulation changes
QC