Induction Sealing

A change in or addition of a seal (e.g., heat induction seal). 

In high-frequency induction sealing a metallic component is located at the point of joining in such a manner as not to inhibit the flow of molten material the inset is designed to ensure a flow of material sufficient to give a seal of the strength required. The method is used mainly for the assembly of moulded components, or for the sealing of plastic bottles in instances where a tamper-evident hermetic seal is needed. 

The next study was conducted in a fashion identical to the initial study in HDPE bottles, except the tablet was placed inside the capsule (overencapsulated tablet) with the tablets as a control experiment. Sure enough, the tablets that were not over-capsulated showed a mass balance issue, while the same batch of tablets inside a capsule showed no mass balance issue. This is very interesting, since the capsule is preventing the loss of assay value. The next obvious experiment was to study the packaging material. The experiment was set up such that tablets were stored in an amber glass bottle and HDPE induction seal bottles for 6 weeks at 40°C/75% RH. In addition, over-encapsulated tablets were stored in HDPE induction seal bottles for 6 weeks at 40°C/75% RH. Results are shown in Figure 15-17. It can be concluded from the data presented in Figure 15-17 that the active was possibly adsorbed to the... 

One packaging (HDPE bottle with induction seal) Multiple packaging Multiple packaging (multiple count bottles, and multiple material blisters) Consumption test (for bottles) Light test (1200 K lux hours) Micro-testing at annual time points (to test the entire packaging operation and to track the changes over time)... 

Finally, containers can be diaphragm sealed using heat (including induction sealing) or adhesive either as the sole closuring means (i.e. peelable tops for unit dose preparations) or in conjunction with any of the other closures previously mentioned. Diaphragms can be a useful means of forming a tamper-evident seal, e.g. used in conjunction with a child-resistant closure. 

Using effective controls, controlled conditions and well-controlled tests constitutes an important part of all investigational experimentation. It is an often neglected subject. Equally such experimentation should be supported by adequate statistical control. Take a situation where a wadded and a wadless (no liner) closure are to be placed on an HDPE bottle and then stored over a 6 month period in a cycling cabinet which cycles between 15°C 50% RH and 37°C 90% RH each 24 h. Question— devise a statisically controlled experiment to check any torque changes, indicating the number of samples required. Personally I would suggest the use of an induction sealed closure as the experimentation could be complex and costly for the information achieved. 

Diaphragms can be applied by adhesive, heat seal or induction sealing after product filling. 

Electrical, e.g. ultrasonic, high-frequency/radio frequency, impulse, induction sealing. Basically a modification of the heat seal process. 

Changes in bottle filler (e.g., change in weight of cotton or amount used) without changes in the type of filler (e.g., cotton to rayon) Increasing the wall thickness of the container A change in or addition of a cap liner A change in or addition of a seal (e.g., heat induction seal)... 

Figure 6.8 Induction sealing (reprinted with permission from [6])...

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