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InPrint - Munich
10-12th November 2015
Hybrid UV - Aquacure™
What, Why, Where and When
2
Who are SunJet?
SunJet is the business unit responsible for digital within Sun Chemical globally
SunJet has stated aim to be the major supplier of ink to packaging, graphics, publication and industrial markets
SunJet has pioneered technology in UV inkjet since 1990’s
SunJet has been an OEM ink partner in wide format since 2000 / 2001
OEM channel is key to strategy
Technology and supply partnerships are the foundation
Integrity is key to partnership
3
What is our core technology?
UK based technical team specialising on the development of,
– Aqueous – Textiles, Publication, Packaging
– UV – Graphics, Packaging (flexible & direct to container) and Industrial
– Hybrid – Graphics, Packaging and Industrial
– Solvent – Graphics, Industrial and Edible
– Oil based – Coding and marking
– Hotmelt – Industrial and Edible
– Ceramic and glass inks – décor and Industrial
Strong links to core R&D teams across Sun and DIC – e.g. Polymer Chemistry, Packaging, Publications, Pigments
4
What is Hybrid UV?
Aquacure™
Aquacure™ is a functional aqueous technology, combining waterbased and UV curing technology.
The water component addresses,
– The feel, film weight and odour
– Health and safety and environmental profile
The UV component addresses,
– Durability
– Jetting reliability
– Media versatility
5
What is the background to Aquacure™?
Aquacure™ technology builds upon Sun Chemical’s leadership in aqueous energy curable inks – WetFlex
– WetFlex was developed for flexo printing of packaging and incorporated aqueous energy curable dispersion technology
– 10 years plus of technology development
Fundamental patented technology for liquid inks and inkjet inks well established
– Additional patenting of long wavelength sensitisation PI’s for aqueous inks now also established for inkjet to accommodate LED curing
Aquacure™ inks contain:
– 60-90% water
– Low level of co-solvent humectant
– UV curable resins/monomers
– Photoinitiators, sensitizers
– Pigment/dispersant
– Additives
6
What does this mean practically?
It’s a truly functional aqueous technology
It requires a dual cure system – both heat and UV / EB cure
Offers good head sustainability
Excellent re-solubility
Significant reduction in product hazard labelling
Low film weights
Very low print odour
7
So how do we cure it?
The new functional aqueous technology must be cured with the following mechanism to produce robust films:
If the functional aqueous ink is exposed to UV curing before it is fully dry then a robust ink film will not be produced.
8
Why dry before cure?
Media Media
IR Drying
Media
UV Cure
UV Reactive Molecules separated by large distances due to dilution with water
UV light exposure cause cross linking of molecules to occur
Removal of water causes UV reactive molecules to “coalesce” together
UV Reactive Molecules =
Cross-links formed by UV
reaction =
Media Media
UV Reactive Molecules =
Cross-links formed by UV
reaction =
9
So what does this all mean?
To produce quality images the hybrid ink must be thermally pinned. This prevents the ink droplets from combining and reticulating.
It is recommended that infrared lamps are installed on the moving carriage or shortly after the printheads in single pass in order to fix the drops as they land and prevent reticulation
Not thermally pinned Thermally pinned
10
So why Aquacure™ - how does it compare to UV?
Low build - it looks and feels like an analogue flexo or gravure print
Lower film weight on final print (10-30% of the thickness of a standard 100% solids UV-curing ink). Prints can thus be around 1-2 microns.
Very low odour
Improve the health and safety profile and product labelling, since materials of higher molecular weight can be used due to the diluting power of the water component
Extended colour gamut due to thinner films
Low migration capability
Better environmental profile than solvent or 100% solids UV due to low VOC and less consumption of material per square meter of print.
11
Aquacure™ offers a sustainable solution?
Ink Type Functional Aq UV-curing Solvent
VOC Content Low Low High
Non-renewable Resource Consumption
Low High High
Aquacure™ inks offer key environmental advantages
12
Aquacure™ offers a sustainable solution?
Aquacure™ inks offer key low VOC inks with high durability
Function Aq UV Solvent
13
Aquacure™ offers a sustainable solution?
SolventUV-Curing Functional Aq
100%
20-
30 %
100%
Aquacure™ inks offer a sustainable solution and key environmental advantages
Non-Renewable Resource consumption
14
Graphics
– Roll to Roll
– Hybrid
– Rigid
Printers and technology exists today
Drive toward more friendly ink solutions due to continuing complexity of chemical legislation
Primary packaging
– Flexible packaging
– Surface Print
– Reverse Print / Lamination
– Food & Personal Care
Packaging sector is keen for digital
Printheads, curing systems and single pass printers now meet packaging sectors needs
A must is the feel and odour of conventional solutions
Where will Aquacure™ be used?
15
Where will Aquacure™ be used?
Carton and corrugated board
– Ideally suited in some respects due to absorption reducing required evaporation
– Existing Flatbed machines can serve this market
– Ink build and general properties allow for improvement over existing UV chemistry with respect to, Odour
Feel
Resistance
Folding.
Aquacure™ the enabling functional aqueous inkjet
16
What could a system look like? Multi-pass
Head Scanning
Preheater for media, heated platen under heads and post print heaters (40-
50C)
Dry printed area entering UV exposure zone
CMYK Printheads
NIR Heaters
Take-up roller
Cured print to take-up roller
Ideally air movement drying (air knife) to accelerate drying
Hot Air Knife
Full Width UV Exposure
17
What could a system look like? Single pass
CMYK Printheads
Interstation IR Drying for spot control?
Print Direction
Drier(Air/IR)
UV Finishing
Water vapour to extraction
UV dose <200mJ/cm2
Print must be dry prior to UV exposure
18
What are the likely drying arrangements? Thermal
Heated platens at 40-55C (variable for media type)
– Pre-heater, under head platen and post print heating
– Pre-heating “opens” the media for better receptivity: wetting and adhesion
– Aids spot control by reducing spreading
– Starts drying of inks
NIR & IR lamps
– Pinning of spots and additional drying
– Suppliers include Adphos, IST, Heraeus and Honle
Adphos NIR Sources
19
What are the likely curing arrangements? UV / EB
UV-cure by full-width array
– On roll-to-roll machines relatively long exposure times will help cure
– LED array? e.g. 395nm stacked array
Instant on/off
Long life/low maintenance
Little heat generation
– EB unit where the additional benefits and security are required
– Multiple UV-lamps mercury or metal halide?
Fragile lamps with routine replacement required
Warm-up time
Cure-All™ Linear 100 ArraySunJet Test Arrangements
ebeam lamp
20
When will Aquacure™ be available?
Aquacure™ chemistry is available
Aqueous compatible printheads are available
Drying techniques are on the open market
Inkjet printer architecture available in graphics and narrow web
Inks are optimised for both scanning and single pass printer architecture
The target markets are ready for digital this technology, consumers like the idea of print being produced with waterbased inks.
Aquacure™ available for application and OEM equipment development now
Any Questions?
working for you.
InPrint - Munich
10-12th November 2015
Hybrid UV - Aquacure™
What, Why, Where and When
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