ebeam technologies - university of manchester

29/05/18Daresbury ebeam Seminar : Curing 1

ebeam Technologies

Curing with ElectronBeam2-Week Training School for the CI programme onAccelerators for Security, Health and Environment(ASHE)

List of Contents

§ EB Curing – some history and applications

§ Drying methods and where EB stands in the landscape

§ Curing Chemistry and Basics

§ EB Curing Printing and Coating Methods


Disclaimer

All Illustrations, Pictures, Products and Companies mentioned arefor the sole purpose of supporting the content and crediting theillustrations used

It is not intended to promote any specific company, brand, productor service


Some(personal)Definition


Curing is the polymerization of a (EB)reactive coating to a solid polymer film

EB CuringSome history and applications


How ebeam works

The 3 effectsGet radicalBreak a bondand then …


ebeam creates radicals

in any organic material

Cut

Link

Paste

… leave it broken

Example: Sterilization

… let it bond to itself

Example: cross-linking ofpackaging material andcables

… let it bond tosomething else

Example: Reactivecompounding, grafting ofbiocompatible materialson membranes

Industrialhistory ofElectronBeam


(Raychem - 1950ies)

Raychem Corp.now Tyco (cable and wire)

Ethiconnow J&J (Sterilization)

WL Grace / CryovacNow Sealed Air (Heat shrink)

3M (Solventless PSA)

Sekisui (PE Foams)

Firestone (Tires)

Others (XL- PVC)

Tetra Pak (Printing)

Ford (Dashboard Coatings)

Microporous (Battery Separator)

1957 70ies 80ies 90ies 2000 2010

Tetra Pak(Sterilization)Manhattan

Project

40ies

History


First Investigation : 60ies

ebeam Applications

Hall of Fame Hydrogels

Structure andPattern Surfaces Furniture Foil

(Past)Magnetic Media


Inks Curing

Lamination

Varnishing

Adhesives

ebeam Printing

PrintingApplications


Juice/milk Detergent In mold Pouches

Shrink sleeve Wrappers Pet food Other

Inks Lamination Adhesives Varnishes and Coatings

MainApplicationsof Curing


More than inks/coatings

The differentmodes ofebeam inConverting


Film Crosslinking Direct Coating/Printing

Adhesives Lamination


The differentmodes ofebeam inConverting


Transfer Coating Backside Embossing / Pattern Transfer

Linear Cathode «Curtain Type» Beam(<300kV)

Scanning Beam(mainly <500kV)


• Widths from 0.25m to 3m• Voltage from 80-300kV

(Printing / Curing typical 80-125kV)• Current from 20mA to 2000mA (typical ~800mA)• Uniformity +-8% typical

• Widths from 0.25m to 2 m• Voltage from 80-300kV

(Scanners not used in Printing)• Current from 20mA to 200mA• Uniformity better than 5% (better possible)

Mainly used in high throughputMainly used in wood panels andhigh uniformity requirements(Adhesives)

Drying Methods and where EB stands in thatlandscape


Introduction

What is electronbeamtechnology?


Thermal UV / UV-LED Electron Beam

Water Based 100% Solid 100% Solid

«Drying»Methods


Solvent Based Hybrid Hybrid

Energy CuringTraditional Drying Methods

Steam / Oxid. (Textiles)

Thermal UV / UV-LED EB

DryingMethods (2)


solvent evaporation

heat

Liqu

idSol

id

VOC

wet weight < dry weight

monomers and oligomers

polymerized coating

no solvent, no PI

wet weight = dry weight

monomers/oligomers/photoinitiator

no solvent

polymerized coating

wet weight = dry weight

Photons Particles

UV / UV-LED EB

DryingMethods (3)

UV vs. EBnumbers


• Energy in the form of photons

• Wavelength determinesenergy; typically 250 to 450nm

• Energy unit conversion; 350nm photon = 3.5 eV

• Total applied energy typically0.1 to 0.5 J/cm2

• Energy in the form of acceleratedelectrons

• Accelerating voltage determinesenergy; typically 80 to 180 kV

• Typical electron energy atsubstrate; >70 keV

• Total applied energy typically 20 to40 kGy

• 1 kGy = 1 J/gram

• For 50 gram/meter2 layer =

0.1 to 0.2 J/cm2

UV / UV-LED EB

DryingMethods (3)

UV vs. EBPenetration


• Penetration depends on theoptical density of the material

• Penetration is controlled bythe peak irradiance (powerand focus) of the UV source

• Good penetration into clearmaterials

• Limited penetration intopigmented, filled, and opaquematerials

• Effective curing of thin inkfilms

• Effective curing of thickcoatings with low pigmentloading

• Lamination of clear materials

• Penetration depends on the massdensity of the material

• Penetration is controlled byacceleration potential (voltage) ofthe beam

• Easily penetrates into clear,pigmented, filled, and opaquematerials

• Can cure thick and/or heavilypigmented or filled inks andcoatings

• Enables lamination of opaquematerials

Thermal UV / UV-LED EB

DryingMethods (2)


Floo

r S

pac

eEn

erg

y R

eq

.

20-100 5-10 1

Sp

ecia

l Req

.

SolventEX-Proof & InsuranceVOC & Incinerator

Water-basedVery long dryers and veryhigh power requirements

InertingLimitiations in Shape of producthigh throughput preferrableEnd-of-line drying

Photoinitiator neededSpecial PI for UV-LEDLimitations for high pigmentationEnd-of-line and Interstation drying

Printing / Coating methods and what drying method can beapplied (excl. Textile)


EB CuringCuring Chemistry and Process


energy cureablechemistriesUV vs. EB basic formulation buildingblocks


Photoinitiator

Additives(functionalproperties)

Monomers(reactive dilution)

Oligomers(base polymer

properties)

Additives

Monomers

Oligomers

UV EB

UV

• Mostly free-radical curing chemistry• Some cationic chemistry• Curing in air or nitrogen atmosphere• PI concentration ~5% (air), <1%(Nitrogen)• PI is a mayor cost component• PI are low molecular weight, PI migration is a

concern in Food Packaging• PI can cause yellowing over time

EB

• (Almost) exclusively free-radical curingchemistry

• Exclusively in inerted atmosphere• No PI needed, direct initiation of

polymerization• High conversion rates typical, high gloss, high

hardness, high chemical resistance

ReacticeOligomer Types

Acrylated Type Characteristics

Epoxies fast curing, hard, solvent resistant, low cost

Aliphatic Urethanes flexibility, tough, non-yellowing, resist to weather

Aromatic Urethanes flexible, tough, lower cost than aliphatic

Polyesters low viscosity, good wetting properties

Acrylics good weathering properties, low Tg

Speciality Resins adhesion, special applications


Tri-functional and higher

Di-functional

Monofunctional

ReactiveMonomerselectrion


Cure Speed Low Viscosity Flexibility Adhesion Residualuncured

Non-ReacticeAdditives

• Pigments

• Fillers

• Deformers

• Flatting Agents

• Wetting Agents

• Foaming inhibitors

• Slip Aids


This energy transfer causesbonds to break in thesemolecules (acrylatefunctionality)

Electrons transfer theirenergy to the monomers/oligomers/ polymers

electrons are acceleratedtowards the print/coating

The result: a liquid to solidfilm within milliseconds

Polymerization occurbetween different molecules

Reactive free radicals aregenerated

How does it work?

How doeselectronbeamtechnologycure inks andcoatings?


- --

--

-- --

--

-

-

✁E

Acrylate chemistry is

proven to work

However themechanism/propagation/film

morphology is less well studiedthan in UV

??????

How does it work?

What is thechemistrybehind this?


H-C=C-C-O-R

H│

H│

O││

Dose

Dose Rate

Speed

Dose 20-60kGy (25-45kGy typical)

Dose Rate up to 12’000kGy m/min

Speed 25-400m/min (100-300m/min typical)

InertingResidual oxygen < 200ppm typical

<50ppm for special applications (Siliconization)

TypicalConditionsfor Curingwith EB


Why choose ebeam?

Benefits ofebeam inprintingand foodpackaging


Consistent Depthof Cure

+High Performance

Colour Blind+

Better Adhesion

Heat-SensitiveSubstrates

Energy Efficiency+

No Heat

Thorough Curing+

Consistent Curing

High Performance+

Constant in Time

No PI Migration+

No Taint/Yellowing

No Photoinitiators+

No PI Odour

EB CuringPrinting Methods


The known slides from many presentations

ebeam for printing applications

5/29/2018Packaging Printing – Industry Overview 33

Printing Technologies

Analog

Offset Flexo Electrophotography Inkjet

Digital

ebeam Printing

Drying processesused in printing


EB UV Oxyd./IR H2O Heat SolventHeat

Sheet-Offset

Web-Offset

CI-Offset

In-Line Flexo

CI-Flexo

Gravure

Inkjet

EB is always End-of-line drying, hence not well suited ifInterstation drying is needed. Printing is wet-on-wet


4 in 1 usingebeamtechnologyenablesfurtherbrand-building andcustomdesigns


Roll Roll

RollRoll

Printing technologies

Offsetprinting withebeam


Innovation:

• EB curing – ebeam Core• easy-to-change rolls• substrates as thin as 12 µm


Flexoprinting withebeam


4-in-1 concept:

• EB curing – ebeam Core• EB lamination in-line• slitting• automatic unloading system


Digitalprinting withebeam


ebeam Compact:

the world’s most compact ebeam


Digitaltechnologyfor customprinting:GAIA

29/05/2018the ebeam (r)evolution 39

• 25m/min (XAAR 1003)

• Aluminium, paper, plastic films

• Food-packaging grade EB CMYK

inks

• Xaar 1003 / Samba printheads

• Variable data

• 350 mm cure width

2.7kW

HP Indigo

• Electrophotographic printing

• Used in a variety of applicationsincluding food packaging

HP Indigo ElectroInk

• Polyethylene-based

• Dried ink is soft and susceptible toabrasion

• Heat sensitiveà melts when heat-sealing even when laminated

HP Indigo Finishing Effects

HP Indigo


Solventless/WB/SB Lamination

• Takes time for adhesive to dryà heat-sealing and slitting delayed

• Reduced depth of image

EB OPV & Lamination

• Instantaneous dryingà immediate heat-sealing & slitting

EB OPV

• Maintained depth of image• Effects: gloss, matte, soft touch• Scratch resistance• Demonstrated food compliance


HP Indigowith EB OPVand EBLamination



HP Indigowith EB SpotEmbellish-ment


Printed varnish on spot areas

• Wet-look and other effects

• Luxury branding

CORE 100Build for Indigo Finishing


Solvent LaminationSolvent-less lamination

EB Lamination

EBLaminationThe natural fit for digitalprinting


• From hours to days betweenlamination and shipment

• Large warehouses needed forprinted product

• Pouching and/or slitting need ahigh level of cure before theprocess

• EB Laminating adhesives cureinstantly

• Slitting can be performed ON THEPRESS right after printing

• Pouching can be performedimmediately after lamination

• No warehousing of goods – shipsdirectly off the press

• Laminating adhesives are stable. Nounnecessary cleaning of coaters

Not ideal for digitalworkflow

Ideal for digitalworkflow

Walking onElectrons:Pattern transferand highresistanceflooring


Cleveland Steel Case

Example:EB/UVHybrid CoilCoating vsSolventbased CoilCoating


18-25 Sec.

8-12 Sec.

3-6 Sec.

Hot Air Convection

Induction Curing or Medium Wave InfraRed

Short Wave or Near InfraRed Oven

UV-Curing2 s.

EB-Curing< 1 s




ELECTRONBEAM

CLEANING

BACKERAPPLICATION

REWINDUNWIND

PRIMERAPPLICATION

TOP COATUV GLOSSCONTROL

TOP COATAPPLICATIONPRIMER

UV CURE

BACKERUV CURE

Before

After




Energy Consumption

Power [MW] Rel.Consumption

Energy Cost[$/year]

Convection (Gas) 15.6 100% 2.5M

IR 9.2 59% 2.5M

EB + UV 0.59 < 4% < 0.2M

EB 0.15UV 0.44

..but functional chemistry has higher baseline cost

Business case is a mix from Energy, Raw Materials, floor space,Insurance cost, Environmental cost

Patent WO2016164220A1

The next stepin ebeamdigitalprinting:

Water-basedEB-curableinkjet ink


b) Soluble dyes and/ordispersed pigments

a) Acrylate functional- monomer- oligomer- or polymer

An electron beamcurable waterbased inkjet inkcomprising:

e) 20-90% waterd) optional non-reactivewater-soluble ordispersible polymers

c) optional additivesPatent WO2016164220A1

Theformulation


< 1cP at 25oC

More scope for formulating to a

jettable viscosity


What is theadvantage ofusing water-based EB-curableinkjet inks?


< 1cP at 25oC

Reduce potential migration:

- Higher molecular weight monomers

- Oligomers

- Polymers


What is theadvantage ofusing water-based EB-curableinkjet inks?


Run yourtests at ourtrial sites


EB provides many benefits:- high performance inks/coatings- environmental

advantages

Proven curing option for safe foodpackaging

Digital printing + EB curingenables brand-building andcustomization:- printing/curing- 4 in 1 technology

Water-based EB-curable inkjetinks:- dry/cure without heat- reduce migration- potential

Conclusions



Get in touch

ContactsMikala [email protected]

Comet AGebeam TechnologiesHerrengasse 103175 Flamatt Switzerland

www.ebeamtechnologies.com

ebeam technologies - university of manchester

Documents