Blister packs sealing

Feeding of products into the blister pockets Fill control system Sealing of the blister pack Application of blister code... 

There are two types of lidding push through and peel and push. Lidding material may be of aluminum foil, paper, or plastic that is coated or laminated to enable sealing to the material of the blister pack. 

Blister Packs. This type of pack can be produced by heat-sealing rigid transparent or translucent film to pre-coated card but vinyl thermoformings can be welded more quickly and the welding technique is more versatile. 

Medicine containers. Reclosable child-resistant containers and blister packs are increasingly used, as is dispensing in manufacturers original sealed packs containing a patient information leaflet. These add to immediate cost but may save money in the end (increased efficiency of use, and safety). 

PP is often combined with PE to achieve desirable properties from both compounds. Commonly selected for its strength, resiliency, and gas/water impermeability, PP commonly constitutes closures and seals. Bags for packaging intravenous fluids are often manufactured from PP stock. Although not commonly utilized in the U.S.A., PP can also be used as a moisture barrier as one layer of a blister pack film. As with all plastics, though, manufacturers of PP should assure users that no additives leach out of the PP resin into the pharmaceutical preparation and quality testing specifications are contained in the USPp ... 

The round, bioconvex, white to off-white NAPS tablets are marked L1A1 and are in a blister pack in a plastic sleeve, each sleeve contains 21 tablets and is sealed in an aluminium foil sachet Ten loil sachets are packaged in one cardboard box. 

All the above processes can also be used in a form fill seal process with, for example, thermoforming and cold forming blister packs. Rommelag type bottle pack systems use an extrusion process where the container is formed by either blowing or vacuum (smaller sizes). Immediately after this, containers are filled, and the pack is sealed (welded) by using the residual heat in an extension to the main body of the container. 

Flexible packaging foil is usually coated with heat sealing material or laminated to other plies that include a heat sealable layer. Lacquered, sometimes embossed, foil is used to lid containers, e.g. blister packs. Foil is used in a wide variety of laminates. However, it cannot be used in any coextrusions, hence alternative barrier materials have to be used. 

Some typical blister packs are shown in Figure 13.12. Various assembly and sealing methods can be used, e.g. ... 

The filling and packaging operations may take place on one piece of machinery or be split across several machines, namely form fill and seal—e.g. blister packs where the product is filled, closed and identified on one machine—whereas a bottle of liquid... 

The types of pack that are sealed straight away on the filling line include blister packs, strip packs, pillow packs, ampoule filling and Rommelag/ALP form fill and seal systems. 

The content of sealed vials and bottles can be qualified using transmission NIR, and non-invasive Raman and NIR cameras have been used to identify the correct filling of blister packs. 

Many tablet medications intended for unit dose applications are protected by the familiar blister packs, an example of which is shown in Figure 10-26. These are typically manufactured with laminated materials that consist of a transparent polymer, an aluminum foil, and an interfacial adhesive. There are many variations of this construction. The transparent polymer layer is first dimpled with a heated die to produce the tablet cavities. The web material, consisting of the aluminum foil and adhesive, is thermally bonded under pressure to the perimeter of the cavities after the tablet is inserted. This is a continuous process in which the line speed, compression force, and temperature must be controlled to assure a hermetically sealed package. 

Instant tack labels find special usage on seals, pleated overwraps, and various header labels. They are not used for bottle or can labeling. Blister and strip packs are classified as part of this category, as we require the temperature of the lacquer to be raised high enough to obtain a permanent bond with the inner surface of the base material. Pressure needs to be applied as well, and usually there will be a knurling implanted onto the mating surfaces. 

Seal width may be as low as 3 mm (small blisters), with 5 mm an advised minimum for sachets and strip packs. Width depends on web wander (a 10 mm width may be used where web wander may be 5 mm, i.e. seal can be 5-15 mm.)... 

Strip packs present an alternative form of pack for a unit dosage. Strips can be produced from single or multi-ply materials, provided the two inner plies can be sealed by heat or pressure (e.g. cold self-adhesive seal). Materials can range from relatively permeable plies to those which incorporate a foil ply of sufficient thickness (and effectiveness of seal) that an individual hermetic seal is produced for each dosage. To date strip packs are usually produced at lower speeds and also occupy greater volume than blisters. The break-even cost with glass containers largely depends on the material used, output speed, and item size. 

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