Christian Ballabio, Product Manager, Pharmaceuticals, ILAPAK
Flow wrapping pharmaceuticals and medical products is a highly specialized area, owing to the production environment, legislative demands and level of seal integrity required. Many considerations have to be taken into account, from hygiene, through to quality control and product tracking.
Today, flow wrapping is increasingly used in the pharmaceutical and medical industries to create an overwrap that provides additional barrier protection, in some cases, allowing the use of cheaper materials in the primary pack. For example, packaging blisters in a flow wrap enables the use of blisters made from ALU-PVC combinations instead of more expensive ALU-ALU. Typically, the wrapping material will incorporate an aluminum layer, to provide a barrier to light, moisture and oxygen. This material presents a number of challenges when creating hermetic seals, owing to its thickness and rigidity.
Here, in this guide to flow wrapping pharmaceuticals and medical devices, we examine some of these challenges as well as the factors manufacturers and contract packers in these industries may wish to consider when selecting flow wrapping equipment.
There are various sealing techniques to choose from: conventional heat sealing, ultrasonics and hot air sealing; each has its strengths for specific applications. Ultrasonic sealing is finding increasing favour in the pharmaceutical industry because it is a cold sealing technique, eliminating challenges around temperature. Ultrasonics is particularly popular with contract manufacturers, as it is capable of switching easily between different wrapping materials. Whereas with heat sealing, operators need to find the right combination of temperature, time and pressure for each different material, with ultrasonics, set-up simply involves changing the frequency via the HMI. The higher capital cost of an ultrasonic sealing unit can be justified by superior performance – high speeds can be achieved regardless of substrate.
That’s not to discount other sealing methods such as hot air sealing, which is often the method of choice for monolayer films. Conventional heat technology relies on the thin layer of sealant on the internal face of the film, usually just a few microns thick, to allow the heat seal, while the outer layers are made with other materials (PET, NYLON, etc) capable to resist to direct heat without melting / sticking. In monolayer materials that is not possible and the heat inertia is higher therefore to reach sealing point all the material (inside and outside faces) has to be melted, with all relative risks of sticking , leaking etc. To overcome this issues, hot air is used, blown from outside on the film to melt the sealant, creating a hermetic seal but without making direct contact with the substrate itself. This technique is preferable and better performing to heat sealing when producing IV bags from 130 micron thickness cast PP at high speed, for example.
Hermetic seal integrity at speed
Pharmaceutical lines typically operate at higher speeds than other industries – 400 ppm is not uncommon for blister lines. This creates a challenge for producing hermetic seals, particularly when sealing thicker substrates, as they require high pressure and high temperatures which usually go hand in hand with long contact times and precise control. ILAPAK surmounts this issue through its dedicated roller and jaw configuration: multiple roller modules in sequence (use of up to five) combined with a transversal sealing solution with modular multiple jaws. This roller arrangement allows temperature sealing management through progressive application of heat (with overall/average lower temperatures), whilst using multiple jaws to create the transversal seal enables prolonged dwell time without compromising production speed. ILAPAK’s top-of-the-range Delta 6000 flow wrapper can comfortably pack at speeds of up to 400ppm, keeping pace with even high speed blister lines.
Temperatures of up to 250 deg C are needed to create the high integrity hermetic seals required by the pharmaceutical industry. This is considerably higher than the temperatures required by other industries. Food industry flow wrappers, for example, rarely seal at temperatures of higher than 170 deg C. Such extreme temperature sealing introduces the risk of substrates melting and sticking to the jaws. On ILAPAK’s flow wrappers, all heated parts are coated with a special treatments that enables a high quality seal to be achieved, without sticking effects and/or any aesthetic impact on finished packs.
The flow wrapper will need often to be designed to comply within the relevant clean room classification/specifications, ISO 5, 6, 7 or 8, for example. For this type of environments, a flow wrapper that won’t generate any dust particles or exhaust air is actually a must. Ensure your flow wrapper supplier uses FDA-rated lubricants, that compressed air systems are fitted with filters that are fine enough to trap particles and that parts that create mechanical friction are enclosed in guards with gaskets to avoid dust particles escaping into the environment.
Any flow wrapper destined for a pharmaceutical or medical device environment must also be able to withstand rigorous cleaning and hygiene regimes. Look for machines on which all product contact parts are constructed from high grade 316 stainless steel or FDA-rated plastic only.
A device that can generate and print 2D datamatrix, barcodes,pharmacodes (usually a thermal transfer printer or laser coder) will be needed for products that fall within the remit of the EU Falsified Medicines Directive (FMD). Compliance with this regulation also requires a vision system that checks data and is capable of OCR/OCV functions. All of these quality control options can be integrated within a flow wrapping line.
Any flow wrapper will also need to comply with 21 CFR Part 11, which means it should have the capabilities to generate electronic records such as complete audit trails, electronic signatures and batch reports necessary for system validation.
Think about the level of validation documentation & support you require from your flow wrapper supplier; do you want to manage your own validation or do you want support in carrying out this procedure?
A joined up approach?
If the flow wrapper is to form part of an automatic line, product handling and feeding will need to be considered. If the flow wrapper is to be integrated with other operations such as blister packaging and cartoning in an automated workflow, there is the question of whether to source the complete line from a single supplier or purchase various machines from different suppliers. The advantages of single supplier sourcing include commonality of spares, a single point of contact for engineering , project management ,servicing and repairs, one supplier taking overall ‘ownership’ for the performance of the line and facilitated communication between different parts of the line. As part of the IMA Group, ILAPAK is the only manufacturer to offer its flow wrappers as a complete line solution, from processing through to distribution and including automated feeding systems, primary and secondary packaging systems. Modularity and quick size change operation is another important consideration if a flow wrapper is to match the multi-format flexibility required by most pharmaceutical producers and packers today.
Make sure you choose an equipment supplier who knows the industry. ILAPAK has vast experience in supplying flow wrappers to the pharmaceutical and medical industries, with an extensive client list that includes Pfizer, Boehringer Ingelheim, Baxter, Mylan, Fresenius, GSK, and many other big names. We have tackled 170 different applications, producing hermetically sealed flow wraps for tablet and capsule blister packs, single dose liquids, ampoules, syringes, inhalers, IV bags and more. Our technical lab in Lugano, Switzerland, offers testing and demonstration services that are key for our pharmaceutical customers. We draw on our library of experience, collated from over 400 installations, perform materials testing and create a unique fingerprint of each customer’s substrate, so that we can predict in advance how it will behave on our machines.