Packing is an integral part of the pharmaceutical industry. The packing is again of different kinds namely bottles, bags, pre-filled syringes, sachets, blister packs, etc.
The blister packs have many advantages because which is popular choice for tablets and capsules by the manufacturers. Some of them include:
- They protect the medicines from moisture and gas to guarantee long shelf life.
- It is very reasonable in price and high volumes can be easily produced.
- They are very easy for usage and are available in a variety of colours.
And the biggest disadvantage of it is that it needs a sealing process to fix to the plastic. In this article we will discuss about the tips can help make sure that there is successful forming, filling, and sealing experience. So, below are the steps:
- Getting Familiar with the Materials:
Various lidding structures need different machine settings and it is always better to use shorter dwell times. Because it promotes high line speeds and also prevents unwanted exposure of drug to the heat.
The consistency of the heat-seal layer must also be checked for. It i.e. the heat-seal layer should be clear, glossy, and resilient to abrasion. When packaging moisture-sensitive products, the heat-seal area is where moisture sooner or later may slip into the package. One can minimize it by keeping away from overly thick heat-seal coatings.
- Sealing Tools:
Sealing expires for solid oral dose drugs particularly those for moisture-sensitive products. They should be designed with at least of 3-mm area between the product-containing cavities, to the outer edge of the blister, date stamps, or perforations. It will minimize moisture entrance through the sides of the package and regulate the impact of micro-channeling. Sealing tools have an effect on the material
- Platen v/s Rotary Sealing:
Platen sealing works best on wide web widths where sealing temperatures are usually lower and dwell times are higher. It presents uniform seal pressure which is particularly significant on the paper-backed structures. Platen sealing machines a lot mean a massive mechanical system which mechanically challenges the foil.
Blister machines with rotary sealing systems are high-speed equipment which operates with narrow webs. Sealing by means of a rotating drum naturally means short dwell time i.e. the sealing area is a thin line. Because the heat-seal coating requires a specific temperature to bond, it takes higher pressure, temperature, and a foil pre-heating station to get a satisfactory seal.
- Processing Conditions:
Stress forming in the bottom web should be avoided. An easy way to check “stress” in sealed blisters is with the help of polarized PET. When held at a 45ºangle, a separate coloration of the formed web will point out stressed areas.
- Sealing Temperature:
Sealing should be done at lower temperatures for minimizing heat i.e. less amount of heat exposure to the drug. It is significant when packaging drugs which consist of large-molecule APIs (e.g., proteins), heat-sensitive excipients, or new drug delivery systems. Additionally, applying less heat to paper-backed structures also helps in avoiding “scorching” of the paper.
Even more less heat in the sealing process may help in reducing blister curl that is introduced while the forming process and is shown when the forming material’s memory effect is stirred up by using heat for a second time. At last, a lower sealing temperature means lower energy consumption which is one-step toward a more sustainable, environmentally friendly manufacturing process.
- Cooling Systems:
During a production day, the cooling systems have varying temperatures and to lessen the difference in the sealing parameters and increase the control of the process, it is best to offer discrete cooling for the forming and sealing stations.
- Test for Leakage:
Leak tests should be done at any cost. It can be divided into two groups namely destructive and nondestructive. Till now, the most general and reasonable destructive blister leakage test is the vacuum test using methylene blue.
