USING INKJET TECHNOLOGY TO DEPOSIT FUNCTIONAL MATERIALS

Transcription

1 USING INKJET TECHNOLOGY TO DEPOSIT FUNCTIONAL MATERIALS Kasper J. Nossent Xennia Technology Ltd Presented at the SGIA Printed Electronics Conference San Jose, USA, June 2011

2 Talk outline Introduction to Xennia Inkjet printing Inkjet drivers & benefits Challenges Industrial solutions Application examples Conclusion

3 Section 1 INTRODUCTION TO XENNIA

4 Xennia helps customers lower operating costs, increase productivity and simplify mass customized production by revolutionizing manufacturing processes

5 Background Xennia is the world s leading industrial inkjet solutions provider 15 year history, over 300 customer development programs World class reputation underpinned by a strong IP portfolio Unique expertise in inkjet chemistry with strong engineering capability Headquartered in UK, offices in US and China Received the Queens Award in 2010 Offering reliable inkjet process solutions: Inkjet modules and inks for OEM partners with market access Printing systems and inks for end users

6 FROM INKJET IDEAS... TO PRODUCTION REALITY ink formulation & test evaluation tools system design production solutions

7 Xennia develops & supplies digital solutions based on inkjet modules, systems and inks for industrial applications

8 Section 2 INKJET PRINTING

9 Inkjet printing A mechanism for controlled ejection of discrete drops of fluid Examples of actuation mechanisms: Deformation of piezoelectric crystals Thermal expansion of bubbles Effectively analogous to a fountain pen, except much smaller! Drop volumes1-80 pl

10 Inkjet printing

11 Inkjet printing Ink channel Nozzle Ligament Satellite Pressure wave Substrate Ejecting ink Drop formation Drop ejection Drop travel Drop on substrate Drop formation controlled by: Rheology Surface tension Viscoelasticity Determined by a complex interplay of: Chemical functionalities Polymer structure Particle size and shape

12 Inkjet printing Ink behaviour on substrate Low surface tension Medium surface tension High surface tension Surface tension of ink relative to surface energy of substrate controls behaviour of ink drops on substrate Printed features are built-up drop by drop Ability to fine tune morphology of printed features by adjusting ink properties UV-cured ink on plastic UV-cured ink on copper

13 Inkjet printing Liquid carrier Surfactants Binders/ bulk matrix Adhesion promoters Rheology modifiers Other additives Functional materials Colorants

14 Inkjet printing Effect of particles Same size as nozzles Slightly smaller than nozzles Much smaller than nozzles Nozzles typically m in diameter Particles in inkjet inks typically sub-micron Development of inkjet inks has been reliant on the development of nanoparticulates Key area of experience is producing stable particle dispersions High density particles tend to settle and reduce reliability Settling prevention - ink formulation and/or recirculating printhead technology

15 Inkjet printing Substrate? End-user? Processing? Porous Non-porous Adhesion Line speed Paper Polymer Scratch resistance Temperature Polymer Metal Solvent resistance UV sensitivity Textile Glass Tensile properties Environmental Solvent-based Aqueous Ink Types UV-curable Oil-based Phase change

16 Inkjet printing Waveform and drive voltage Flow through the nozzle Droplet formation and jet stability Image quality and durability

17 Inkjet printing Adhesives Abrasive materials Aggressive acids and alkali materials Anti-scratch materials/clear coats Biomedical antibodies, reagents and enzymes Bronze, aluminium and molybdenum powders Ceramic pigments Colloidal and emulsion materials Conductive graphite Conductive metals Conductive polymers Decorative metallic pigments Electrochromic materials coating Inorganic pigments Inorganic phosphors and lanthanides Magnetic materials (MICR) Media coating materials Metal solutions and dispersions OLED and LEP materials Organic soluble and dispersed dyes Sintered metals and ceramics Textile pigments and dyes Titanium dioxide Ultra high purity materials UV cure pigment inks UV cure structural polymers UV clear

18 Section 3 INKJET DRIVERS & BENEFITS

19 Inkjet drivers & benefits Key market driver for inkjet technology Need for economic short print runs Faster and more frequent product upgrades Increased number of niche products Increased number of national/regional variations Increased demand for personalisation to added value

20 Inkjet drivers & benefits Reduced production costs Efficient use of consumables No requirement to produce new screens/pads Short runs are economic Cost per print same for 1, 10, 100, 1000, 10,000 No requirement for inventory Increased productivity No time for set-up printer is always printing Faster response Print on demand Just-in-time customisation/personalisation Ideal for all types of substrates

21 Section 4 CHALLENGES

22 Challenges critical areas Wetting, drying, curing Ink chemistry Fluid control Substrate Print heads Encoder accuracy Material handling Drive electronics, software

23 Challenges Challenges can be broken down into Ink/substrate Print Quality System

24 Challenges - ink Specific application requires specific ink PE applications require very specialised inks Vital requirements for ink Printed ink must display required functional performance Ink must print reliably under production conditions Second requirement often forgotten Ink development requires testing Extensive/integrated Functional performance Inkjet performance

25 Challenges - ink Need to overcome tendency to agglomerate Ionic or steric stabilisation chemical stability Dispersion process Mill particles with dispersing agent Breaks up agglomerates and coats with agent Stable Agglomeration Physical stability Balance between Brownian and gravitational motion Mixing versus settling Dense and/or large particles settling Overcome with agitation/recirculation

26 Challenges ink & substrate

27 Challenges ink & substrate

28 Challenges ink & substrate

29 Challenges quality Original (256 levels) Binary Head 7 Level Greyscale

30 Challenges quality Output from greyscale printhead Viewed close individual dot sizes visible Perceived by human eye from a distance

31 Challenges quality Digital halftoning Variable no. of drops Different ink densities Directly vary drop volume Regular screen, dither, stochastic Needs very small dot size and high resolution to give good results Same ink density, small drops Reduces throughput as multiple drops/pixel Multiple ink densities Requires multiple nozzles - extra cost Extra ink tanks Variable drop volume requires Close printhead manufacturing tolerances Excellent temperature control Well behaved and consistent inks Vary waveform according to drop size Increases head complexity No loss of pixel frequency

32 Challenges quality Why graphics printing DPI is a myth Higher is better (the myth) Grey scaling allows higher perceived DPI with lower native DPI 100% coverage is the max In printed electronics DPI is a key driver Need for discrete drops (binary) High drop density (material density) High drop accuracy

33 Challenges quality

34 Challenges quality

35 Challenges - quality

36 Challenges system Understanding failure modes is key in designing industrial inkjet solutions Typical failure modes for inkjet are: Nozzle blockages Nozzle plate contamination Air inclusion Drop substrate interaction fails Consumable failures (filters, dampers) Failure modes to take into account that are non inkjet: Mechanical shocks Standing waves in piping/beams Vibrations (Eigen Frequency) Influence of temperature/moisture Mechanical deformation/expansion

37 Challenges - system

38 Challenges system Typical options to increase reliability of print process Spitting nozzles Purging In process Wiping nozzle plate Capping printheads Optimizing ink for the printhead and process and substrate Optical systems to detect nozzle failure Camera s to inspect printed product Nozzle redundancy Modular approach Redundancy Design

39 Section 5 INDUSTRIAL SOLUTIONS

40 Industrial solutions Balance between Quality Productivity Cost Size Reliability Systems covering a broad range of configurations Batch production Continuous/web production 3D printing Development/materials deposition

41 Resolution (dpi) Industrial solutions 600+ Desk top thermal and piezo DOD inkjet Industrial piezo DOD inkjet The best compromise of speed and resolution for most industrial applications Raster continuous inkjet Binary continuous inkjet Speed (m / min)

42 Industrial solutions Fail and act 100% Redundant Low System Cost High Low Efficiency High The optimal solution should be determined based on the final specification of the process Understanding the failure modes of the system and the jetting process is a key element in the pilot setups

43 Industrial solutions Print engine Software Fluid controllers

44 Industrial solutions

45 Industrial solutions Printing system/ modules Ink Substrate Reliability is a function of ALL parts of the process Need to ensure ALL parts of the process work together

46 Industrial solutions Printed Electronic Solutions Range of requirements for PE inkjet printing systems Development systems Ink and process development/testing Batch processing systems Testing, prototyping, pilot production, batch production, high accuracy Continuous production systems High throughput production (rigid and flexible substrates) 3D surfaces?

47 Industrial solutions Xennia Carnelian Lab scale and development system High precision 3-axis A4 printer for accurate materials dispensing All major piezo printheads Fully programmable XYZ motion stage with sub-micron resolution Options: UV lamp, vacuum stage, fiducial alignment camera Repeatability of ±5µm over printable area Flexible platform can be customized for specific requirements Integrated printing software Technology scalable for production

48 Industrial solutions Xennia Carnelian CARNELIAN MOVIE

49 Industrial solutions Jetxpert Measure: Drop volume (down to 1pl) Ligament volume Velocity Trajectory Visualize: Ejection Formation Misting Face plate wetting Optimize: Print parameters Drive wave forms Driving voltage

50 Industrial solutions Xennia Sinopia High precision development and batch production system Substrate sizes from 350mm x 350mm through to 1600mm x 1200mm Granite base, air bearings and linear motors giving repeatability of ±1µm Up to 8 printheads (all major piezo supported) Print speeds up to 300mm/s Options Z axis, vacuum and heated stage UV and IR lamps, alignment camera Class 100 cleanroom compliance Integrated print software

51 Industrial solutions Xennia Sinopia SINOPIA MOVIE

52 Industrial solutions Xennia Viridian 280 mm wide reel-to-reel printer Multi-fluid fixed array print unit Over 1000dpi resolution 24m/min at full resolution Printing onto flexible substrates Polymers Paper Metal foils

53 Industrial solutions Printing onto 3D Substrates 3D printing onto a general surface First application safety helmets Multi-stage process Flame treatment White+cure CMYK+cure

54 Section 6 APPLICATION EXAMPLES

55 Application examples

56 Section 7 CONCLUSION

57 Conclusion Biggest challenge is to get the applications out of the lab into industry Biggest implementation barriers High development costs, no economy of scale All applications are bespoke No or few commercial inks Generic print systems don t exist Industrial inkjet is proven Systems proven Modular components proven Software is proven

58 Conclusion Ink technology is proven in lab environments Needs to be optimized for the application Needs industrial up scaling Growing rate of industrial implementation in niche applications Stand alone systems Integrated systems Replacement of analogue systems

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