Inkjet Printing Inkjet Technology Fundamentals Rafi Bronstein Rafi
Inkjet Printing Inkjet Technology Fundamentals Rafi Bronstein Rafi. Bronstein@HP. com Mobile: 054 -531 -3760 July, 2008 Rafi Bronstein
Inkjet Technology and Inkjet Printing Rafi Bronstein Rafi. Bronstein@HP. com 2008 July, 2008 Rafi Bronstein
Course Syllabus n Inkjet technology history and fundamentals u Types on inkjet technologies u History of inkjet printing u Industrial applications n Most successful inkjet printing technologies u Continuous inkjet technologies u Drop-on-Demand inkjet technologies l Thermal inkjet l Piezo inkjet l Novel ink ejection technologies July, 2008 Rafi Bronstein
Course Syllabus n Print head fabrication materials and processes n Print head designs and key vendors u Thermal inkjet u Piezo inkjet u Direct ink ejection n Piezo print head design parameters u Frequency, crosstalk, drop placement accuracy … July, 2008 Rafi Bronstein
Course Syllabus n Printing inks and their composition u Ink types and properties n Inkjet printing substrates u Paper and coatings u Non-paper media n Basics of radiometry and basic color theory u Radiometry u Color systems and color management July, 2008 Rafi Bronstein
Course Syllabus n Ink drying and curing technologies u Drying u Curing n Drop-on-demand ink droplet deflection techniques u Sony u Kodak u Others July, 2008 Rafi Bronstein
Course Syllabus n Inkjet printing systems design n The printing industry n Digital printing and inkjet printing July, 2008 Rafi Bronstein
Ink Jet Printing Methods Classification July, 2008 Rafi Bronstein
Ink Jet Printing History (I) n 1878 – Lord Rayleigh n 1929 – Hansell, USP #1, 941, 001 Electrostatic Deflection Recorder n 1938 – Genschmer, USP #2, 151, 683 Spark Type Ink Ejector n 1946 – Hansell, USP #2, 512, 743 Jet Sprayer Actuated by n n n Piezoelectric 1958 – Winston, USP #3, 060, 429 Drop Jetting by Electrostatic Attraction 1962 – Naiman, USP #3, 179, 042 Sudden Steam Printer 1964 – Sweet, USP #3, 596, 275 Continuous Inkjet Printing 1966 – Hertz et al. USP #3, 416, 153 Modulation by Electrostatic Dispersion 1967 – Sweet et al. USP #3, 373, 437 Array of Continuous Ink Jets July, 2008 Rafi Bronstein
Ink Jet Printing History (II) n 1970 – Kyser et al. USP #3, 946, 398 Drop-on-Demand Bend Mode n n n n Inkjet Apparatus 1970 – Zoltan, USP #3, 683, 212 Squeeze Tube Piezoelectric Inkjet 1972 - Stemme – USP #3, 747, 120 Bend Mode with Metal Diaphragm 1979 – Endo et al. GBP #2, 007, 162 Electrothermal Transducer (Bubble jet) 1982 – Howkins, USP #4, 459, 601 Piezoelectric Push Mode 1982 – Vaught et al. USP #4, 490, 728 Electrothermal Transducer (Thermal Inkjet) 1979 - 1985 – Fishbeck, USP #4, 032, 929 - USP #4, 584, 590 Shear Mode Transducer 1989 – Bartky et al. USP #4, 879, 568 Droplet Deposition Apparatus July, 2008 Rafi Bronstein
Ink Jet Printing n Continuous n Drop-On-Demand (DOD) u Piezoelectric u Thermal (Bubble) inkjet n Others July, 2008 Rafi Bronstein
Lord Rayleigh – Drop Formation Law (I) d P V L λ Emerging from an orifice liquid jet breaks-up into droplets. Because of the surface tension: • Droplets have random size • Droplets have random spacing July, 2008 Rafi Bronstein
Lord Rayleigh – Drop Formation Law (II) d P L = K*ln(d/2α 0)V(ρd 3/σ)0. 5 V L λ = 4. 51 d; fs = V/4. 51 d λ α 0 – the initial disturbance ρ - the density of the fluid σ – the surface tension of the fluid L – break-up length fs – the frequency of spontaneous drop formation λ – wave length July, 2008 Rafi Bronstein
Drop Formation – Ink Jet Basics n Can the drop size be controlled? n Can the spatial spacing of the drops be controlled? n Can the break-up length be controlled? n What would be the drop selection method? July, 2008 Rafi Bronstein
Sweet-type Continuous Ink Jet Deflection Plates Pressure Charge Electrodes Gutter Substrate July, 2008 Rafi Bronstein
Binary Continuous Ink Jet Deflection Plates Pressure Charge Electrodes Gutter Substrate July, 2008 Rafi Bronstein
Is It So Simple? Viscosity Density Change in Viscosity with pressure July, 2008 Rafi Bronstein
Drop Charging Methods Plate Charging (Sweet) Tunnel Charging (S. Bahl? ) Plate Face Charging (S. Bahl? ) July, 2008 Rafi Bronstein
Drop Charge Requirements and Limits Drop charge limits: (Rayleigh limit) • Electric field between the electrodes • Conductive ink • Inductive charging • Charging voltage • Charging electrode shape • Jet break-up parameters Q = Sq. Rt. (64π2ε 0 r 3σ); ε – free space permittivity σ – surface tension r – drop radius July, 2008 Rafi Bronstein
Drop Deflection Plates Pressure L Charge Electrodes Gutter Substrate • Electrostatic deflection field • Aerodynamic drag force • Neighboring drops repulsion Deflection on paper X = (q. E/m. V 2)L(D-(L/2)) Where q, m, and V are charge, mass and drop velocity. L- length of the deflection plate. D – distance from the plate edge to the substrate. July, 2008 Rafi Bronstein
Density modulation (W. Lloyd & H. Taub) Substrate Mask Charge electrode Substrate Nozzle Charge electrode Mask V V Charge electrode Drop dispersion on mask/aperture V July, 2008 Rafi Bronstein
Density modulation (H. Hertz) Deflection Plates Pressure Charge Electrodes Gutter Substrate • Variable number of drops per pixel July, 2008 Rafi Bronstein
Key Inkjet Patents (I) July, 2008 Rafi Bronstein
Key Inkjet Patents (II) Zoltan July, 2008 Rafi Bronstein
Piezoelectric Materials Ceramics poling July, 2008 Rafi Bronstein
Piezo effect and Piezoelectric Deformation 0 - 0 + + - July, 2008 Rafi Bronstein
Piezoelectric Materials (I) July, 2008 Rafi Bronstein
Piezo effect and Piezoelectric Deformation 0 0 - + + - July, 2008 Rafi Bronstein
Elements of Piezoelectric Inkjet technology Source: S. Negro and E. Smouse, Hewlett-Packard Inkjet Printing Technology: The State of the Art, 1999 July, 2008 Rafi Bronstein
Key Inkjet Patents (III) July, 2008 Rafi Bronstein
Drop-on-Demand Piezoelectric Inkjet Piezoceramic Membrane Manifold Pressure chamber Orifice Inlet Orifice plate July, 2008 Rafi Bronstein
Drop Ejection Process: • Push-on • Draw-push July, 2008 Rafi Bronstein
Forces Acting on Ink Drop VCarriage • Drop charge • Electric field of the substrate • Ejection frequency • Nozzle plate state • … VDrop Windspeed H Drug d daero July, 2008 Rafi Bronstein
Elements of Thermal Inkjet (print head structure) Source: S. Negro and E. Smouse, Hewlett-Packard Inkjet Printing Technology: The State of the Art, 1999 July, 2008 Rafi Bronstein
Elements of Thermal Inkjet (how it works) Source: S. Negro and E. Smouse, Hewlett-Packard Inkjet Printing Technology: The State of the Art, 1999 July, 2008 Rafi Bronstein
Elements of Thermal Inkjet (drop ejection process) Source: S. Negro and E. Smouse, Hewlett-Packard Inkjet Printing Technology: The State of the Art, 1999 July, 2008 Rafi Bronstein
Thermal Inkjet Configurations Source: S. Negro and E. Smouse, Hewlett-Packard Inkjet Printing Technology: The State of the Art, 1999 July, 2008 Rafi Bronstein
Key Inkjet Patents (IV) Canon 1977 - 1988 July, 2008 Rafi Bronstein
Key Inkjet Patents (V) HP July, 2008 Rafi Bronstein
Key Inkjet Patents (VI) Fishbeck July, 2008 Rafi Bronstein
Key Inkjet Patents (VI) Fishbeck July, 2008 Rafi Bronstein
Key Inkjet Patents (VII) July, 2008 Rafi Bronstein
Key Inkjet Patents (VIII) Bibl Micro. Fab July, 2008 Rafi Bronstein
Key Print Head Characteristics n Resolution n Drop ejection frequency n Drop volume n Drop speed u Array pitch u Drop speed uniformity across the array u Operating temperature range u Physical size and weight July, 2008 Rafi Bronstein
Print Head Resolution – Print Resolution n Pitch between two neighboring nozzles u Actual resolution u Linear array u Two dimensional array n Electronic resolution u Minimal printable distance between two successive dots July, 2008 Rafi Bronstein
Drop Ejection Frequency n Minimal time between two successive drop ejection cycles u System resonance u Fixed frequency u Plurality of ink ejection frequencies n Defines throughput July, 2008 Rafi Bronstein
Drop Speed n The speed at which the drop leaves the orifice u Aerodynamic resistance u Multi drop grey scale printing u Ejection force u Ink parameters n Defines printing speed n Drop speed variations July, 2008 Rafi Bronstein
Effect of Drop Speed Variations July, 2008 Rafi Bronstein
Drop Volume n The volume of the ejected drop (picoliter; nanogram) u u Drop volume variation as function of ejection frequency n Defines amount of ink on the substrate and accordingly image color gamut July, 2008 Rafi Bronstein
Tektronix Print head US Pat. No. 5, 155, 498 July, 2008 Rafi Bronstein
Drive Signal Form US Pat. No. 5, 155, 498 July, 2008 Rafi Bronstein
Various Drop Formation Wait Periods. Signal of Fig. 2. US Pat. No. 5, 155, 498 July, 2008 Rafi Bronstein
Drop Flight Speed with Signal of Fig. 2. US Pat. No. 5, 155, 498 July, 2008 Rafi Bronstein
Another Form of Drive Signal US Pat. No. 5, 155, 498 July, 2008 Rafi Bronstein
Print Head Pressure Changes with Drive Signals of Figs. 6 -7. US Pat. No. 5, 155, 498 July, 2008 Rafi Bronstein
Crosstalk Between the Channels July, 2008 Rafi Bronstein
Drop Volume as Function of Ejection frequency US 5, 274, 400 (HP) July, 2008 Rafi Bronstein
XAAR XJ 500/360. VEEjet. July, 2008 Rafi Bronstein
Q&A n Do you have any questions? July, 2008 Rafi Bronstein
Thank you July, 2008 Rafi Bronstein
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