WE like to understand what is happening inside the material So YOU do not have any problems from the outside 1
Numerische Simulation zur Entwicklung innovativer Verpackungen in Pharma und Medizintechnik Packaging Innovations Science meets Industry 28.03.2014 Matthias Schellenberg, Neuhausen am Rheinfall
About Suisse Technology Partners An independent development service provider with long term experience Engineering Physical & chem. analytics Polymer lab Material testing 1888 2000 2009 2011 3
Diffusion physics Barrier is inversely proportional to film thickness! 0 WVTR P d 1 g/day d ½ d 1 g/day 2 g/day 4
Thickness distribution Barrier is inversely proportional to film thickness! Film thickness varies due to forming process (e.g. thermoforming) WVTR 3 g/day 2 g/day 1 g/day ½ d d film thickness d 5
Thermoforming simulation What is the best packaging design for your product? Polymer lab Simulation of the thermoforming process Thickness distribution Prediction of barrier properties Geometry optimization Process optimization Structural analysis Blister: Medipack AG 6
WVTR [g/day/cavity] Thermoforming simulation How do different materials perform? Film thickness distribution Comparison of different film materials (WVTR / OXTR) 1.2E-04 1.0E-04 8.0E-05 6.0E-05 4.0E-05 2.0E-05 0.0E+00 Film 1 Film 2 Film 3 7
Plug assisted Thermoforming 8
Thickness [mm] Simulation needs material testing & validation Material testing & characterization Simulation Validation 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Measurement Simulation 0 2 4 6 8 X-Coordinate [mm] 9
So, how can numerical simulation help? Is numerical simulation too complicated? Material data? Why not only testing? The simulation allows to understand the issue without extensive testing View into the material helps to learn about cause and effect: What is happening? Product & process optimization (no fabrication of tools etc.) Prediction of barrier, shelf life, failure, process parameters, etc. Quicker to the market Reduced risk of product recall Is testing easier? 10
Laboratory is important! Investigation of blister sealing pattern quality Sealing pattern investigated by scanning electron microscope (SEM) Sealing pattern by computer tomography (nondestructive) 11
Laboratory is important! Investigation of blister sealing pattern quality Micro section of coldform foil Voids section Sealing pattern investigated by scanning electron microscope (SEM) Indentations of sealing tool 12
Barrier properties of CFF Where and why does cross diffusion occur? Lid foil Sealing Layer Cross diffusion Base foil Lid Top layer Aluminum Heat seal lacquer Main polymer Adhesive Base Aluminum Bottom layer Diffusion distance Relevant layers for cross diffusion 13
Barrier properties of CFF Humidity concentration Humidity flow 14
Barrier properties of CFF CFF blister Corner cavity, no perforation Mid-strip cavity, no perforation Mid-strip cavity, perforated Mid-strip cavity, perforated & lateral offset 2mm Humidity flow 100 % 55 % 180 % 190 % 15
WVTR [g/d/cavity] Influence of lateral offset in production How does a lateral offset influence cross diffusion? 1.2E-06 1.0E-06 170 % 8.0E-07 6.0E-07 100 % 4.0E-07 x 2.0E-07 0.0E+00 0 1 2 3 4 5 6 7 X [mm] 16
Relative WVTR [%] Barrier properties of CFF How do different materials perform? 120% 100% 80% 100% 72% 60% 40% 41% 20% 0% CFF Material 1 CFF Material 2 CFF Material 3 Aluminum HSL Aluminum HSL Aluminum HSL Polymer 1 Polymer 2 Polymer 3 Adhesive Adhesive Adhesive Aluminum Aluminum Aluminum 17
Relative humidity inside [-] Water absorption [g] Transient cross diffusion simulation How long does it take to reach a certain humidity? Humidity increase in (empty) cavity Water absorption of content (e.g. tablet) 0.8 0.7 0.6 0.5 0.4 Perforated cavity Corner cavity @ 40 C, 75 %RH 5.5E-03 5.0E-03 4.5E-03 Perforated cavity Corner cavity @ 40 C, 75 %RH 0.3 4.0E-03 0.2 0.1 3.5E-03 0 3.0E-03 0 500 1000 1500 2000 time [days] 0 500 1000 1500 2000 time [days] % RH g 18
Transient cross diffusion simulation 19
Water Ingress [g] WVTR [g/d] CFF with Desiccant Development of a diffusion model for CFF with desiccant to predict the shelf life of high moisture sensitive products 3.0E-06 WVTR [g/d] Total water ingress [g] 2.5E-06 2.0E-06 1.5E-06 1.0E-06 5.0E-07 0.0E+00 3.0E-03 2.5E-03 2.0E-03 1.5E-03 1.0E-03 5.0E-04 0.0E+00 Standard CFF Blister CFF Blister with Desiccant 0 1000 2000 3000 4000 5000 6000 7000 time [d] Standard CFF Blister CFF Blister with Desiccant 0 1000 2000 3000 4000 5000 6000 7000 time [d] 20
The combination of ANALYSIS, MATERIAL CHARACTERIZATION & SIMULATION is the key to success for the solution of complex issues 21
Matthias Schellenberg Suisse Technology Partners Ltd. RhyTech Areal Bad. Bahnhofstrasse 16 CH-8212 Neuhausen am Rheinfall web: http://www.suisse-tp.ch Email: matthias.schellenberg@suisse-tp.ch Tel: +41 52 551 1188 22