Integrated lines used to improve efficiency

In the first article of a two-part investigation into blister packaging machinery and materials, Andrew Smith looks at the latest industry hardware trends and installations

The perceived and inherent value of blister packs continues to ensure their popularity with manufacturers, medics and consumers alike.

Indeed, blister packs have a growing 30% of the world market in primary pharmaceutical packs and have firmly secured their place as one of the sector's most popular presentation methods.

But are blisters the 'Holy Grail' pharmaceutical packaging technologists have long sought ; the perfect pack at bargain basement prices?

The answer, of course, is no; even packaging technologists have some way to go before they can walk on water.

Two factors prevent the blister's elevation to sainthood. On performance, it is the child resistance (CR) factor which, according to some, lets the blister down, but this point will be investigated more closely in next month's focus on blister packs and materials.

The incontrovertible factor is cost. Firstly, the material costs associated with blisters outweigh those of a simple plastic pot with a tamper-evident CR cap.

Moreover, while pots can, if needs be, go onto the shelf unadorned by secondary packaging, blisters must be cartoned or carded, which further adds to time and costs.

Blisters will, therefore, merely remain hugely successful as opposed to all conquering with their use 'restricted' to medium and high margin products, or those where the blister pack's superiority is crucial, such as calendar packs.

In response to the overall cost factors affecting the blister packaging operation, machinery suppliers are doing their best to ease the pain with faster, more versatile set-ups. One way of doing this is to provide blister lines with integrated cartoners under the control of one PLC, a route taken nowadays by a number of suppliers. The obvious logic being that if the pack invariably has to be cartoned, then make the cartoner a part of the set-up to ensure optimum feeding and, hence, overall control and compatibility.

Typically, this route dispenses with the need for blister magazines to transfer the blisters from the packer to the cartoner, which has a number of advantages. As blister feeding is continuous, higher speeds can be achieved and downtime is reduced as the task of manually re-stocking magazines is eliminated. The potential magazines have for being the source of misfeeds is also removed.

Kloeckner Medipak can supply a choice of three such integrated lines dependent on the size and output required. The company says a number of design factors has contributed towards a small footprint, ease of accessibility to all parts of the machine and reduced downtime.

The compact design of the machines, which are available in the UK through F.J. Pistol Machinery, is due to a split-level configuration with some stations mounted vertically and diagonally to reduce the machine length. Three separate zones are claimed to guarantee clear segregation of the functional areas of the blister machines, particularly the dosing area which can be maintained under negative pressure preventing dust contaminating the functional area, 'thus dramatically reducing clean down time', according to the company.

These latest models ; the CP200, 400 and 1200 blister machines and P1500 and 3000 cartoners ; also see the introduction of servo technology for Kloeckner. All drive units and mechanical and electronic controls are mounted to the rear of the machine for ease of access and segregation of products, materials and drives.

A reduction in downtime is achieved via the ability to change the base material without stopping production, coupled with low level mounting of the lidding material, which eases reel changes. All machines also have the option of roller sealing or platen sealing allowing flexibility on the range of films and foils which can be used.

Transfer of the blisters to cartons is achieved with direct stack formation and insertion, which avoids the need for conveyors and stacking magazines, thus eliminating a potential source of misfeed. High-speed cartoning of blisters has also been simplified by adopting a twin-feed mechanism on the P3000. Two carton blanks are drawn off and erected together and two blister stacks are inserted simultaneously, allowing the production of up to 300 cartons/min.

Operation is via a touch screen terminal, which stores and retrieves machine set-ups and collects and evaluates data from the line.

However, before the blister packing process can take place, the product must be fed correctly to the machine to ensure accurate placement while protecting the integrity of the tablet or capsule. One of the specialists in this field, Electro-mec, has now introduced a number of enhancements to its EMF line of feeders and the new EMFD range includes a series of design improvements, which are said to provide the machines with even greater GMP compliance.

In addition, to make the machines more user friendly several operator benefits have been incorporated, including a hinged guard, which gives easier access to the machine, and the re-siting of the control panel to the front of the machine.

But however accurate the feeding and the blister machine are, misfills, empty pockets and so on will still occur and the products will have to be removed from the blister. The latest in Sepha's line of automatic deblistering machines is claimed to be the world's first 'jam-free' model and ideal for peelable and 'problem' blisters. The Press-Out Universal deblister machine is said to be able to handle blisters of all shapes and designs ; including circular, diagonal or irregular layouts ; as well as curled blisters. Fragile tablets with break lines, and those that are very small or unusually shaped, can also be coped with.

The company says a new design uses minimum pressure to completely invert each pocket, which results in a 100% recovery yield. Capable of operating at speeds up to 50 packs/min, the Press Out Universal uses dedicated tooling for each design, ensuring full GMP compliance.

Tool-less changeover takes two to four minutes and the machine is sold as maintenance-free with a lifetime guarantee.

Sepha has also introduced Blisterscan, which it describes as 'the new affordable and non-destructive leak tester'. Using sensor technology, the tester replaces the 'blue dye' test, but is clean, dry and non-destructive, thus reducing wastage by allowing the return of 'passed' blisters to the line.

The test cycle takes 30 seconds and it will detect leaks and weak seals as small as five microns across a full cross-section of the blister web. Product changeover takes two minutes, with two low-cost plates required for each different blister format.

Tablet recovery system helps boost productivity

Generic drug manufacturer Alpharma of Barnstaple in Devon has just installed a fifth blister packing line based on an IMA C90 blister packer/cartoner, feeding finished product directly onto a BFB Compact Palletiser. While similar to the previous four lines, on this latest C90 the blister packing section has been configured to maximise production and minimise waste. To achieve this the C90 is equipped with a tablet recovery system that not only makes it easier to re-use any tablets removed from incomplete or rejected blisters but also ensures that any waste material is ready for recycling. Once a blister is formed and tablets fed into the pockets, a colour camera is used to check that every pocket is full. If an empty pocket is detected but all the other pockets contain complete tablets, all the good tablets are sucked out of the pockets at the first reject station and fed directly back to the product infeed station to be repacked immediately. If the camera detects chipped tablets or particles within a pocket, the blister passes on to a second reject station where the contents are recovered for sorting prior to re-use. Further along the line, a second, black and white camera is used to check that all blisters being rejected are completely empty before they are fed to the waste collection station, so ensuring that all the material collected is free from contamination and ready for recycling. The C90 employs IMA's rotary forming system that allows all types of blister materials to be used including combinations of aluminium foil and PVC, as well as alu/pp, pp/pp and alu/alu.

Noack builds reputation for reliability

Reliability and reduced downtime are two of the most sought after attributes when it comes to choosing machinery and the Noack 623 is steadily building a reputation as one of the most robust packers on the market. Pharmapac UK took delivery of the first 623 to be installed in the UK less than a year ago and it has now produced several million packs at efficiencies in excess of 90% with no technical problems experienced. ‘Indeed," says Pharmapac operations director, Andrew Sampson, ‘the only parts we have replaced have been four springs on the stamping out plate, which could well be regarded as consumables." Pharmapac's machine was the first of seven 623s now operating in the UK market, where it has been particularly successful in the generic and contract packing sectors. The supplier of the Noack range, Romaco, says the key to success is the simplicity of the machine's design ; based on a single shaft drive ; which assures ease of maintenance and low manufacturing costs. As a result, ‘it is considerably less expensive than its competitors, yet offers significant outputs of up to 450 blisters per minute". ‘The operating efficiencies," says Sampson, ‘are extremely high compared with the industry norm of 70%. The 623 runs day in, day out, producing 30,000 completed packs per day." Another highly successful contract packer, Swindon-based TD Packaging ; which has expanded its turnover to an estimated £4.5 million in just five years of operation ; has backed Noack with the installation of a further two blister packaging lines to complement the existing three in operation. The first line is fully automatic and comprises a rotary sealing Noack 920 blister packer plus Promatic P150 cartoner and Sollas overwrapper and the second consists of a platen sealing Noack DPN 760 blister packer and Promatic BIPAK cartoner, both featuring extended beds for improved access. The new lines represent a significant increase in TDP's blister packing capacity. However, such is the demand for blister-packed products, that director and co-founder Martin Tedham is confident that the new lines will give rapid payback. TDP says being at the forefront of new trends in the market is essential and it has therefore been working closely with capsule manufacturers in conducting stability trials on new, non-gelatine soft gel capsule formulations. New blister packaging substrates, such as Kloeckner Pentaplast's Pentapharm COC, have also been tested successfully by TDP on the Noack 920, thus ensuring that it can handle the requirements of any job, whatever the specifications.

Aventis chooses EMF for chevron pack

With a requirement for accurate and flexible blister pack filling across a variety of different products and pack formats, Aventis Pharma has installed two EMF3 tablet and capsule blister pack feeders from Electro-mec at its Dagenham site. The first EMF3 has been installed to enable the company to pack capsules into blisters laid out in an already produced chevron format which are difficult to pack effectively because the forms are at an angle. This requires a definite placement of each capsule into a form to ensure accurate filling as the capsules will not drop naturally, making traditional methods such as brush box feeding inappropriate. As the EMF 3 has individual feed tubes positioned over each blister, it was ideally suited to the job. Aventis has also now installed a second EMF3 to be used in conjunction with another blister packer to pack standard tablets. In addition to the two feeders, the company has three interchangeable feed bowls ; two for capsules and one for tablets ; which offer the flexibility to pack capsules on both machines when required. A similar problem has been solved by the installation of an EMF1 feeder at Dutch contract packer Tjoapack, which had a requirement to pack an awkward, flat shaped tablet into a chevron blister. Previously tablets had to be hand fed into the blisters and the new feeder has now substantially increased packing speed.