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57 Cards in this Set
- Front
- Back
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Tensile Properties |
ability to resist a direct pulling force Modulus of elasticity Elastic elongation Resilience Tensile strength Toughness |
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Modulus of elasticity |
resistance to elastic deformation |
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Elastic elongation |
farthest a material can be stretched without permanent deformation |
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Resilience |
ability of material to absorb energy and return to original dimensions |
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Tensile Strenght |
maximum tensile stress material can sustain |
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Toughness |
energy material can absorb before rupturing |
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Tensile Properties |
Converting and packaging machinery Stretch Films Personal care packaging |
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Dimensional Stability |
ability of a material to maintain its dimensions when exposed to environmental changes temperature, humidity, MD, TD |
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Dimensional Stability Application & Test Methods |
during converting, filling, distribution match of materials and processing conditions ASTM D 1204 - linear dimensional changes of flexible thermoplastic films and sheets at elevated temperatures |
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Optical Properties |
visual appearance of film App. - marketing, shiny vs matte, visibility vs hiding Test ASTM D 2457 - gloss ASTM D 1003 - haze, transmittance |
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Coefficient of Friction |
measure of friction between two surfaces resistance to moving a film in surface to surface contact with itself or another material To high - difficult to move material To low - too slippery Static CoF - force need to start Kinetic CoF - force need to sustian |
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CoF App. and Test Methods |
Machinability Stability Ease of package handling Test - Static CoF TAPPI T503 ASTM D 1894 |
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Barrier Properties |
resistance to permeation oxygen & water/ moisture carbon dioxide, flavor/aroma, crispness desired and undesired chemicals Product protection and shelf life ASTM E96 - water vapor transmission rate ASTM D 1434 - oxygen permeability |
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Heat Seal Characteristics |
ability to heat welded to itself or another material Temperature, Pressure, Time run speed, compatibility with seal maintain desire seal strength seal peel-ability |
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Surface Tension/ Energy |
ability of a film's surface to be wetted by calibrated solutions adhesion, wetting, printing, surface treatment laminate, adhesive, inks ASTM D2578 -surface tension by contact angle |
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Hydrophillic Surface |
Good for surface tension low contact angle good adhesiveness good wettability high solid surface free energy |
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Puncture, Impact and Burst Strength |
resist fractures pressure required to produce rupture withstand distribution stress ASTM D1709 - determine weight of dart which rupture film ASTM D3272 - determine kinetic energy lost by a dart as it passed thrus film ASTM D3420 - pendulum impact test ASTM D256 - notched Ixod impact strength STM D774 - bursting strength |
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Tear Strenght |
resist tearing withstand stressed during distribution Ease of opening ASTM D1004 - force required to initiate tearing ASTM D1922 - energy required for propagation of a tear after it is initiated by small hole ASTM D1938 - standard procedure to evaluate tear strength of film along MD and TD |
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Aluminum Foil Basics |
most widely used non-ferrous metal absolute barrier to protect foods shelf, cooler, freezer lightweight, easy and economical form-able, shape, size printed coated or embossed recyclable |
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Aluminium Foil History |
1940s - bakery product 1960- aluminum containers now - 12 B containers, 400 M lbs |
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AFCMA |
Aluminum Foil Container Manufacturers Association |
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Alumimun Properties |
impermeability and barrier properties mechanical and air pressure to force light-gauge aluminium foil into a shaped die cavity variety of colors and special coatings prepare, freeze, store, transport, cook, serve microwave conventional convection and boiler |
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Aluminium Package |
packaging and food service industry consumer friendliness, tri-oven-able, recyclable, comparison of aluminum foil containers microwave ovens |
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Aluminium Future |
consumer convenience and fresh and fresh-like foods stronger growth in the US markets |
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Aluiminium Background |
abundant metallic element 8% of the earth's crust aluminum ore, bauxite 50-60% aluminum oxide last of common metallic elements 1886 discovered the electrolytic reduction process that frees an aluminum from oxygen |
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Aluminium Production |
molten salt (cryolite - Na3AIF6) at temperatures of 900 to 1000 C oxygen being released at the carbon anodes pure metal reduction cell and cast |
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Rolling Aluminium Metal |
continuous cast metal received hot metal billet form meet desire foil specifications and cast into sheet metal that may be from 0.2" to 0.04" reroll stock gauge and shipped to a foil plant rolls next to metal = work roll higher or variable loads to be absorbed mill with two back-up rolls is 4 high mill thicker at the middle than edges slightly reducing oil spray on a part of a mill rill with in cause it to heat slightly at the spot and increase pressure on the metal 75% gauge reduction coil form in annealed resulting metal is softened and rolling oil are removed |
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Aluminum Coating and printing |
protect the container from corrosive food, products or add color for both aesthetic and functional purposes |
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Aluminium Slitting |
slit to the appropriate width to transfer to the aluminum foil container manufacturer lubricant transferred in coil form to the final forming operation |
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Aluminum Foil Container Formation |
presses that are fed from coil of feed stock single or multiple container single operation chopped and bale for recycling back into new container feed stock number of shapes and sizes |
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Advantages of Aluminum Containers |
perfect package for numerous food packaging application consumer friendly - not change containers, little space, leak-resistant, fresher, clean up easy, versatile, speed up baking.freezing Tri-ovenable - regular, toaster, microwave Recyclable |
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Alumium Foil Design and Application |
number of markets retail markets oven and burner liners Distribution 35%, bakery 25%, packer 15%, retail 15%, supermarkets 10%, nonfood small% |
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Adhesion |
process where two initially separate substrates are held together by inter-molecular forces solvents to dissolve the interface allowing intermingle at molecular level inter-molecular forces and physical entanglements adhere any combination - paper, glass, metal, plastic, ceramics |
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Adhesive Example |
Paper & Aluminum - solvent based liquid adhesive (Paper/adhesives/Foil) 2 sheets of Plexiglas - dichloromethane, molecular entanglement heat sealing, LDPE intermingles with itself then adheres when cooled |
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Adhesive Applications |
forming and sealing paper-bags cores cans and drums paper and plastic labels lamination pressure sensitive tapes and labels |
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Adhesive Zones |
Substrate #1 Interface between 1st substrate and adhesive adhesive interface between 2nd substrate and adhesive Substrate #2 |
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Adhesive Bond Types |
adhesive bond strength - adhesive to surface of substrate cohesive bond strength - strength within the adhesive |
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Adhesive Force |
interface between the substrate and adhesive interface - inter facial forces hold substrate together complex - controlled by surface tension (wettability) solubility parameter and viscosity |
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Cohesive forces |
intermolecular attraction within a material secondary forces within material chemical nature and physical state temperature and molecular weight M. WT, Cohesive strength, viscosity increase Wettability decrease |
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Adhesive Treatments |
Corona Discharge Flame Treatment Plasma Treatment |
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Types of Adhesives |
Hot Melt Adhesives Solvent Based Adhesives Water based Adhesives Re-moist-enable adhesives pressure sensitive cold seal adhesives |
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Hot Melt Adhesives |
100% solid - no solvents needed hot to wet surface, cools to solid Adv. quick set, no chemicals and solvent emissions Disadv. - poor performance at elevated temps Ex. - adhesives based on EVA |
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Solvent Based Adhesive |
based polymer dissolved in an organic solvent strength develops as solvent evaporates Emiisions - VOCs ex. - polyurethanes, EVA system |
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Water Based Adhesives |
base polymer suspended in water develops as water evaporates Natural - starch, animal glue, casein Synthetic - base polymer in water (colloids, plasticizes, fillers, preservatives) Adv. - no solvent emissions Ex. - EVA system, acrylics, polyurethanes, syn. rubbers |
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Re-moistenable Adhesvies |
affixed to another substrate at a later time water based |
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Pressure Sensitive Adhesive |
retain tack when cool or dry carrier web recloseable openings |
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Cold SEal Adhesives |
natural rubber stick to themselves but not to much else two parts of wrap s activated no heat heat sensitive products (ice cream, candy) dressing applications |
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Multilater Film Processes |
Co-extrusion Lamination and Coating Extrusion (lamination) adhesive lamination Wet or dry bonding |
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Laminations |
bonds two or more webs to crate a single web paper,plastic films, surface coating, aluminum foils, metallized films, metallized paper held together by - adhesives, polymers, tie layers |
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Coating |
at least one web of material thinner and lighter than lamination less costly |
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Extrusion Coating |
overcoats heat seal and barrier coatings, laminating adhesives waterproofing, dying and preservative functions 1st web |
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Extrusion Lamination |
2nd web is added combined by the adhesive action of the extruded thermoplastic material |
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Adhesive Lamination |
coating onto surface of one web before joining the second web Dry bond Wet bond Glue |
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Dry Bond Lamination |
applied to 1st substrate then dried 2nd substrate joined by a heated nip against the first |
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Wet Bond Lamination |
applied to one substrate the two substrates are nipped together while wet sent though an oven one web must be porous to allow the adhesive solvent or water to excape |
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Example Chip Bag |
EPB Co-polymer -sealing Polypropylene - clarity Print -Graphics LDPE - inter-later adhesion Metal Layer - barrier Polypropylene - stiffness EPB Co-polymer -Sealing |
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Exmples Layer |
Opp 17/print/dry laination/OPP 22 OPET12/print/pex12/Al-9/pex15-lpex60 OPET12/print/dry lamination/OPET 12/pex20-ipex40 |
