Get it right the first time: tips on maximizing efficiency in blister packaging

Posted by sere on March 11th, 2020

For technical products in many industries, small details are often modified without significant visual or functional changes perceived by customers.

Manufacturers of these products or equipment implement these changes to save costs, simplify the manufacturing process or make the product more reliable.

Often, these changes are relatively simple to introduce because there are no regulatory restrictions;

As long as the customer is happy, there will be no feathers wrinkles.

Of course, the pharmaceutical industry is a completely different industry. -

Not only is the change of the product closely watched, but it does not seem

Significant adjustments to product packaging require a lot of financial and human resources.

Generally, there must be sufficient proof that the modification has no negative impact on the product and/or the end consumer. This show-your-

Work validation on change effectiveness can add a lot of time and cost to the entire modification process.

The best way to avoid changing the packaging of a drug is simple: do it right the first time.

Of course, it\'s easier said than done.

However, a variety of best practices can be implemented to help shorten the development time before the introduction of the product and avoid subsequent costly modifications.

For example, it may be beneficial to create an internal virtual model

Development Package--

Can help the engineer to determine the preliminary steps of factors such as ideal packaging materials, which for avoiding deficiencies

Expensive packaging and unnecessarypackaging.

There are also tools that can help make appropriate decisions about processing performance, and those that take into account the efficacy factors of the \"if/then\" product that may have been overlooked in other ways.

Here are tips on how to use these tools to make packaging development a more efficient and rigorous process.

Barrier properties: for many years, choosing ideal materials has been a trend in which drugs are becoming more and more sensitive to moisture.

In order to fully protect the drug from moisture and reach the required shelf life, packaging materials that provide an appropriate moisture barrier must be selected.

For stability testing, specific packaging specifications are usually selected during the development phase;

This packaging specification can of course be used if the test is successful.

However, what this test will not reveal is whether you are really over-doing it.

In fact, the results of the stability test do not indicate whether the specification with a lower water vapor barrier is sufficient.

For example, even if the thin barrier foil is already sufficient, a thermoformed laminate with a relatively thick barrier foil can be specified.

The same is true for Poly diammonium (PVDC)

Coating and its coating weight.

If a material with insufficient water vapor barrier is selected for stability testing, the test will not pass.

When this happens, additional testing must be carried out to determine the appropriate packaging material, which will result in additional costs and delays.

For this reason, the reasonable trend is that packaging developers overcompensate by using protective barriers beyond what they think they need to pass the exam.

Here, fear of failure replaces strict optimization. -

Expensive overpackaging as an unfortunate side effect.

Fortunately, this guessing game can be largely marginalized by simulating the barrier properties of various packaging types to achieve the ideal material selection for stability testing.

This is a particularly attractive option when there is a fairly wide range of thermoforming blister film specifications to choose from.

For example, PVC/PVDC laminate with various coating weights or ACLAR/PVC laminate.

Simulation is particularly useful for thermoforming laminate because the barrier of the blister cavity they form can only be estimated to a limited extent using the barrier properties shown in the technical data sheet provided by the supplier.

This is because these data sheets refer to the barrier value of the unformed flat laminate, which can be misleading.

During cavity formation, the laminate becomes thinner and the barrier decreases accordingly.

This situation becomes more complicated due to uneven thickness of the laminated material, because some areas of the cavity are thinner than others.

In order to distinguish between truly reliable values, the degree of thinning and the resulting obstacles must be simulated.

In this regard, the aluminum laminate is generally superior and provides a \"trump card \".

This is because the aluminum in the laminate has a 100% blocking effect on water vapor (and oxygen).

In addition, the barrier property of aluminum has nothing to do with its thickness;

Cold foil provides the same barrier to water vapor and oxygen after deep stretch as before deep stretch.

Even with the choice of cold foil, this inspection still makes sense.

As mentioned earlier, cold foil provides the highest barrier against water vapor.

However, there is a big difference in cold-state blocking performance associated with cross-penetration effects.

That is, a very small amount of water vapor can enter the cavity from the perforated edge of the blister.

A suitable simulation can prove whether it is desirable to use a cold foil with polyethylene (PE)

Instead of PVC (PVC)

To reduce this possibility.

Another viable option may be the cold foil with desiccant to absorb moisture from the Crossmigration.

The forming performance of the base laminate is limited, which must be considered in the cavity design of the blister package.

If the laminate is over-stretched during deep stretching--

Whether it\'s thermoformed or cold-formed ---

There may be serious tears or fine holes that reduce or even completely eliminate protection.

Even if detected in these errors --

Lines, due to increased waste and reduced productivity, poor cavity design can lead to higher costs.

And worse

Case scenario: none of these defects were found-

Given that not all the holes are equal, this is a daunting prospect.

If a fine hole is formed due to the defective cavity design, the coldform foil provides the advantage that these defective blister packages can be packed with so-

Called \"bullet hole detector\"

\"This type of inspection does not exist for transparent thermoforming blisters.

Therefore, it is essential to have a comprehensive understanding of material limitations during the development phase, especially in terms of material limitations associated with cavity formation.

In most cases, FE-based (finite element)

Simulation can help experts make appropriate suggestions.

This simulation helps to compensate for inconsistency in the degree of material stretching that occurs during cavity formation.

Here, the area with the highest elongation cannot be predicted based on experience, but must be calculated (simulated)

Because there are a lot of parameters that work.

There are also some cases where the existing (forming)

Tool design must be used and there are no detailed technical drawings.

In this case, the maximum elongation can be checked by measuring.

This is done by deep stretching the laminate that has printed the \"high definition mesh.

By evaluating the grid after deep Flushing, it is possible to determine whether post-production must assume a high scrap rate.

If this is the case, the design of the forming tool should be modified.

The effect of temperature usually, the packaged product is affected by a certain temperature, because the lid foil and the substrate will be heated during the blister seal.

The degree of heating depends on many parameters, such as the thermal conductivity of the laminate being used, the melting and sealing temperature, and the sealing time. FE-

Simulation-based tools can be used to estimate the impact of temperature-

An important step, especially when packaging potential temperature-

Sensitive products.

The results will affect not only the selection of the laminate, but also the specific foil/laminate combination.

For example, due to the low sealing temperature of PE laminate, it may be beneficial to use PE\'s cold forming on cold forming of PVC.

Since small holes in aluminum are very rare, it is difficult to find test samples that can be used to measure the impact of small holes in aluminum.

Even if they do happen, the limits on the detection device bring it close-

It is not possible to measure the overall negative impact of the fine holes in the laminate and paint foil.

Here, the simulation can estimate the barrier reduction caused by pinholes and the results used to estimate the possible impact of moisture penetration caused by pinholes on a given product.

For example, this may help if it is necessary to determine the aluminum thickness of the packaging laminate, or the cover foil of the blister package.

After all, the lower the aluminum thickness, the higher the probability that it will produce small holes.

This simulation can be used to estimate whether thin aluminum foil poses a risk to the product.

Abstract simulation is a valuable tool to find ideal materials during packaging development.

In terms of material investment, the cost of inappropriate or excessive use of materials is not necessary;

Of course, the risk of insufficient materials is greater.

Identifying the right materials as early as possible and the production process of using them can avoid unnecessary accidents through the best packaging solution.

Thomas Schwartz is a development engineer in the pharmaceutical division of Constantia Flexibles, which provides the start of integration-to-finish, foil-

Packaging solutions for the pharmaceutical and nutrition industries in North America.