Flexible Packaging Printing Processes Overview

1 2009 Consumer Packaging solutions for Barrier Performance CourseFlexible Packaging Flexible Packaging Printing Processes Printing Processes OverviewOverviewPresented by:Warren E. DurlingAssociate Research FellowThe Clorox Company (GLAD) Flexible Packaging Printing Processes OverviewSlide 22009 Consumer Packaging solutions For Barrier Performance CourseFlexible Packaging Printing Processes OverviewSlide 32009 Consumer Packaging solutions For Barrier Performance CourseThe Basics of Flexible Packaging PrintingDEFINITION:Applying ink to a substrate to produce an image or textPRINTING METHODS:Flexography and Rotogravurethe two most widely utilized methods for Flexible PackagingFOCUS:Design to Substrate; the process describedStructures and Print locationUnderstanding InkSubstrate Surface PreparationMethods and Equipment in detailReproduction Basics.

2 Line and process printingFlexible Packaging Printing Processes OverviewSlide 42009 Consumer Packaging solutions For Barrier Performance CourseDesign to SubstratePreproduction Design CreationSubstrate ManagementImage Preparation Color SeparationInk ManagementCylinder or Plate MakingConverting Press Cleaning and MaintenancePrintingPrintingPress Make ReadyFlexible Packaging Printing Processes OverviewSlide 52009 Consumer Packaging solutions For Barrier Performance CourseSURFACE PrintingFlexible Packaging Printing Processes OverviewSlide 62009 Consumer Packaging solutions For Barrier Performance CourseREVERSE Printing 2 Layer StructuresFlexible Packaging Printing Processes OverviewSlide 72009 Consumer Packaging solutions For Barrier Performance CourseREVERSE Printing 3 Layer StructuresFlexible Packaging Printing Processes OverviewSlide 82009 Consumer Packaging solutions For Barrier Performance CoursePRINTING INK, form & chemistryyPhysical form Liquid free flowing 30% to 60% solids and 100% solids UV/EB Relatively low viscosity (closer to water than heavy syrup)yChemistry Solvent based gravure, flexographic Water based flexographic, (gravure) Radiation (UV/EB) cured flexo, (gravure) Flexible Packaging Printing Processes OverviewSlide 92009 Consumer Packaging solutions For Barrier Performance CourseRESINS Used in Packaging Printing InksyCommon Nitrocellulose Cellulose (cotton linters) Polyamide Rosin (crude tall oil) Acrylic Petrochemical (styrene and acrylic acid) Phenolic Rosin (gum derived)

3 YSpecialty Acrylate used in UV/EB inks & coatings Epoxy used in UV/EB inks & coatings Urethane used in solvent and UV/EB inks and coatingFlexible Packaging Printing Processes OverviewSlide 102009 Consumer Packaging solutions For Barrier Performance CourseTypical PIGMENTS in Packaging InksOrganics: Carbonblack Diarylideyellow Pyrazoleneorange / red Disazogreen shade yellow, red, orange Naphtholred, brown, violets Pthalocyanine green, blue Quinacridone redInorganics: Titanium Dioxidewhite Iron Oxidesyellow, red, brown Metallic (Aluminum) silver, gold Claygreen, red, yellow, brownFlexible Packaging Printing Processes OverviewSlide 112009 Consumer Packaging solutions For Barrier Performance CourseBasic INK Formulation ExamplesWATER65%SOLUTIONRESIN 10%EMULSIONRESIN 10%SOLVENT65%POLYAMIDERESIN 10%NITROCELLULOSERESIN 10%Reactive DiluentsUp to 30%ACRYLATEMONOMERACRYLATEPREPOLYMER55%C ontent provided by theWaterSolventRadcure80% ALCOHOL20% ACETATEADDITIVES 5%ADDITIVES 5%ADDITIVES 5%PIGMENT10%PIGMENT10%PIGMENT20% - 25%Dry InkDry InkWet InkWet InkDry Ink&Wet InkFlexible Packaging Printing Processes OverviewSlide 122009 Consumer Packaging solutions For Barrier Performance Course161-140110-60579-78410-60464 to 596 12-60319 to 156 20-60 210-3640-601 Centistokes Range Seconds Efflux TimeCup NumberPRINTING INK.

4 Viscosity measurementZAHN Cup conversionsSHELL CupCENTISTOKE is the unit of reference in all viscosity cup measurementsSECONDS (time) is the Operator press side measurementPOISE is the fundamental unit of viscosity defined as the resistance of a liquid to flow where gravity is not a CENTIPOISE = 1 POISE. Gravity is the driving force causing liquid in a viscosity cup to flow through the orifice so a high density material will flow from a cup in a shorter time than a low density material of the same is defined as the POISE divided by density. 100 CENTISTOKES = 1 STOKE. ZAHN CupFlexible Packaging Printing Processes OverviewSlide 132009 Consumer Packaging solutions For Barrier Performance CoursePRESS SIDE Ink Management1) PUMP & MOTOR2) INK TANK3) FILTER4) Printing STATION5) AUTOMATIC VISCOSITY CONTROLF lexible Packaging Printing Processes OverviewSlide 142009 Consumer Packaging solutions For Barrier Performance CourseTREATMENT - Substrate Surface Preparation Most plastics such as polyethylene, polypropylene and polyester have chemically inert and nonporous surfaces with low surface tensions causing them to be non-receptive to bonding with Printing inks, coatings and Treatment Systems increase surface energy to promote adhesion for Printing , coating, laminating and other converting Processes .

5 Most all substrates including paper and foil will exhibit increased adhesion to inks, adhesives and extrusion coatings after surface Packaging Printing Processes OverviewSlide 152009 Consumer Packaging solutions For Barrier Performance CourseAn electrical process that uses ionized air to increase the surface tension of , corona treatingsystems operate at an electrical voltage of 10 kV. The high voltage is applied across an electrode which ionizes the air in the electrode/web gap, creating a highly energized corona. CORONA Treatment Flexible Packaging Printing Processes OverviewSlide 162009 Consumer Packaging solutions For Barrier Performance CourseLike corona, plasma is the electrical ionization of a gas. Unlike corona, plasma is created at much lower voltage levels and the rate at which electron bombardment occurs is up to 100 times greater.

6 Plasma facilitates the use of chemical gases which can produce controlled chemical reactions to functionalize surfaces. PLASMA TreatmentContent provided byFlexible Packaging Printing Processes OverviewSlide 172009 Consumer Packaging solutions For Barrier Performance CourseThe process of burning away surface contaminants by forciblyspraying a flame onto a substrate surface. This is accomplishedby burning an ultra-lean gas mixture, whose excess oxygen is rendered reactive by the high TreatmentFlexible Packaging Printing Processes OverviewSlide 182009 Consumer Packaging solutions For Barrier Performance CourseTREATMENT - determining the treatment level DYNE Test solutions of various percentages of Ethyl Cellosolve, Formamide and Water Dyne solution levels range from 30 to 60+ The treatment level is based upon the specific solution number that wets out the surface vs.

7 The next level up that beads up Easy and cheap test method well suited for use on the shop floor Procedure can be subjective but is reasonably accurate ifadequate care is taken and the solutions are kept freshReference ASTM D257850+42 PET38-4531 OPP38-4531 LDPET reatedUntreatedFlexible Packaging Printing Processes OverviewSlide 192009 Consumer Packaging solutions For Barrier Performance CourseTREATMENT - determining the treatment level CONTACT ANGLE Contact angle is the angle formed by a liquid at the three phaseboundary where a liquid, gas and solid (substrate) intersect Very precise measurement with high repeatability Requires a relatively expensive test instrument that is not wellsuited for shop floor use The lower the contact angle, the higher the treatment levelReference ASTM D5946-04 GoniometerFlexible Packaging Printing Processes OverviewSlide 202009 Consumer Packaging solutions For Barrier Performance CourseFLEXOGRAPHY PrintingFlexography.

8 (often abbreviated to Flexo) A form of relief Printing where ink is applied to a rubber or polymer plate on which the Printing image is raised above the rest of the surface as a 3-D positive mirrored Packaging Printing Processes OverviewSlide 212009 Consumer Packaging solutions For Barrier Performance CourseFLEXOGRAPHY Printing - processFlexible Packaging Printing Processes OverviewSlide 222009 Consumer Packaging solutions For Barrier Performance CourseFLEXOGRAPHY Printing - plate structureFlexible Packaging Printing Processes OverviewSlide 232009 Consumer Packaging solutions For Barrier Performance CourseFLEXOGRAPHY Printing - anilox rollsThe anilox roll is a steel or aluminum core cylinder with a ceramic surface that contains millions of very fine cells. They are specified by their "line screen", or the number of cells per linear inch ranging from below 250 to above 1500.

9 Lower line screens are used to print a heavy layer of ink such as block lettering. The highest line screens produce fine detail for four-color process work such as reproducing Packaging Printing Processes OverviewSlide 242009 Consumer Packaging solutions For Barrier Performance CourseFLEXOGRAPHY Printing - pressesFlexible Packaging Printing Processes OverviewSlide 252009 Consumer Packaging solutions For Barrier Performance CourseROTOGRAVURE PrintingRotogravure: (typically referred to as Gravure) An intaglio process (in-tal-yo means engraved or cut in)in which a negative image is etched into the surface of a copper Printing cylinder as tiny cells or dots of various sizes and depths. The copper is chrome plated for durability. Ink is applied to the surface and a Flexible metal blade called a doctor blade removes excess ink, leaving the surface clean, with ink only in the Packaging Printing Processes OverviewSlide 262009 Consumer Packaging solutions For Barrier Performance CourseGRAVURE Printing - processFlexible Packaging Printing Processes OverviewSlide 272009 Consumer Packaging solutions For Barrier Performance CourseGRAVURE Printing - cell structureFlexible Packaging Printing Processes OverviewSlide 282009 Consumer Packaging solutions For Barrier Performance CourseAcid Etching ( diffusion -Etching and Direct-Transfer) Light sensitive gelatins or photopolymers on the coper surface are exposed through a film positive of the image resulting in varying levels of acid resistance.

10 The surface is exposed to acid, resulting in cells of the same size and cell wall thickness but varying Engraving -The original copy is scanned into a computer and digitized. The computer then controls a diamond stylus that cuts the cells into the surface of the gravure cylinder. Cell depth and cell area are varied simultanously by using a tapered engraving head. Laser Engraving The method of choice to produce Flexo anilox rolls with some applications in gravure Printing . An original is scanned into a computer, the various image densities are determined, and lasers etch the cylinder. Highly reflective copper is a poor material choice so alternative special alloys, plastics and ceramics are used. GRAVURE Printing - cylinder engravingFlexible Packaging Printing Processes OverviewSlide 292009 Consumer Packaging solutions For Barrier Performance CourseGRAVURE Printing - electrostatic discharge ESAF lexible Packaging Printing Processes OverviewSlide 302009 Consumer Packaging solutions For Barrier Performance CourseGRAVURE & FLEXO Printing - doctor blade designFlexible Packaging Printing Processes OverviewSlide 312009 Consumer Packaging solutions For Barrier Performance CourseGRAVURE Printing - pressesFlexible Packaging Printing Processes OverviewSlide 322009 Consumer Packaging solutions For Barrier Performance CourseLINE PrintingSingle colors are printed at varying densitiesIndividual colors do notoverlap or