Functional and Energy
Efficient Textile Coating
Systems
F. Terzioglu, E. Rohleder, M. Rabe
Research Institute for Textile and Clothing (FTB), Hochschule Niederrhein
Functional and Energy
Efficient Textile Coating
Systems
Content
I. Conventional textile coatings vs. UV coatings
• UV curing vs. thermal curing
• UV coating technology I. Research Projects
• Development of textile coatings based on UV curing
• Development of energy and resource efficient NIR sensitized textile
Content
I. Conventional textile coatings vs. UV coatings
• UV curing vs. thermal curing
• UV coating technology
I. Research Projects
• Development of textile coatings based on UV curing
• Development of energy and resource efficient NIR sensitized textile
Introduction
Motivation for new technologies in the field of textile coating
make textiles more suitable save energy and time accentuate or inhibit
natural characteristics impart new characteristics
improving standard wet processes
water-free technologies
• textile coatings are generally solvent based or aqueous
• crosslinking induced by thermal energy
• radiation-curable coatings based on acrylates
• crosslinking by radical or cationic polymerization
UV coatings – 100%-systems
• radiation-curable coatings based on acrylates
• crosslinking by radical or cationic polymerization
UV coatings – aqueous dispersions
UV curing vs. thermal curing
Content
I. Conventional textile coatings vs. UV coatings
• UV curing vs. thermal curing
• UV coating technology
I. Research Projects
• Development of textile coatings based on UV curing
• Development of energy and resource efficient NIR sensitized textile
Requirements for UV coatings
UV radiation reactive C=C UV/NIR coating bondenergy dH 613 kJ/mol = 201 nm UV A – C = 200nm – 380nm energy photoinitiatorsLight sources
• Lamps • LEDs • Lasers
UV initiated radical polymerization
+
+
UV/NIR radiation radicals polymerization cured film initiation propagation resin photoinitiator terminationFormulation for UV coatings
resin/oligomer monomer (reactive diluent or water) photoinitiator additives • film properties • scratch resistance • abrasion resistance • elasticity • reactivity • viscostiy • crosslink density • reactivity • UV-dose • levelling • deaeration • gloss degree• thickener (for waterb.)
Content
I. Conventional textile coatings vs. UV coatings
• UV curing vs. thermal curing
• UV coating technology
I. Research Projects
• Development of textile coatings based on UV curing
• Development of energy and resource efficient NIR sensitized textile
Research projects
1. Development of new energy saving textile finishing methods for technical applications, based on UV curing
2. Photoinitiators for resource efficient and energy saving polymerzations
The projects were funded by German Federal Ministry of Economics and Technology (BMWi) via „Zentrales Innovationsprogramm Mittelstand“ (ZIM), under grant number KF 2914003BN2 and KF 2233809MF3.
NIR-coating-system
• NIR-radiation well known as thermal energy source
• also usable for sensitized photopolymerization processes • initiator system consists of two components
NIR – LED arrays I
Research HS-Niederrhein:
NIR-Photopolymerization and New Light Sources
NIR-LED arrays
- small range of emission suitable to
the sensitizer
- low intensity
- requires development of more
intensive LEDs in different
wavelengths including UV, visible
and NIR
IR-radiant heater
- wide range of emission
- small amount of usable emission
Research HS-Niederrhein:
NIR-Photopolymerization and New Light Sources
NIR-LED arrays
- small range of emission suitable to
the sensitizer
- low intensity
- requires development of more
intensive LEDs in different
wavelengths including UV, visible
and NIR
IR-radiant heater
- wide range of emission
- small amount of usable emission
• small range of emission suitable to the sensitizer
• low intensity
• requires development of more intensive LEDs in different wavelengths including UV, visible and NIR
NIR-LED arrays II
• atmospheric curing process with 6 LEDs
• solubilty problems of the coinitiator => solution = three roll mill
• oxygen inhibition results in non
completely cured surface => solution = inertisation
NIR-LED arrays III
• experimental setup with an inertbox
• coating with a wire-bar applicator • purging with nitrogen
• curing with 6 NIR-LED arrays
good curing in depth and surface
good reactivity
FT-IR analysis shows a conversion
NIR – Laser
• laser: 808 nm, focus 0.6 mm, 135 W
• high energy output = shrinking and melting • less energy output = no surface curing
UV vs. NIR
UV• high sensitivity
• established curing system
• problematic with pigments or
light stabilizers
• harmful UV light
• requires safety light shielding
NIR
• less sensitive than UV systems
• unknown to coating-technology
• yellow, red and blue pigmented
coatings
• curing of layers upto several mm in just one step
Summary
+ reduced energy consumption and environmental impact + fast drying/curing
+ no solvents (VOC)
+ high production speeds + little space required + low equipment cost
+ suitable for themosensitive fibres
+ high chemical and mechanical resistant
ozone generation (only for UV; not for NIR) monomers/oligomers
Acknowledgement
We wish to thank A. Joßen, C. Schmitz, M. Schläpfer, T. Brömme, B. Strehmel, for their work and ideas promoting these research results.
Contact
Research Institute for Textile and Clothing (FTB) Hochschule Niederrhein Webschulstraße 31 41065 Mönchengladbach Fikret Terzioglu Tel.: +49 2161 – 186 6029 [email protected]
