27/12/2023 Corporate news

What is paneling in a plastic container?

“Paneling” in a plastic container is the phenomenon in which the walls of the container deform or collapse, generating visible ripples or wrinkles. Paneling is the deformation of the sides of the plastic container when it is subjected to external/internal pressure. This can happen during the storage, transportation, or handling of the products.

Paneling can have a negative impact on the appearance of the packaging and, in some cases, can affect the integrity of the packaged product and, of course, the image of the manufacturer brand of that packaged product.

We will talk about…

  1. Paneling phenomenon: Why does a plastic container with chemical formulations inside collapse?
  2. Paneling in a plastic container: What factors cause the paneling of a package and how to avoid it?
  3. Compatibility testing packaging vs Packaged product


Paneling phenomenon: Why does a plastic container with chemical formulations inside collapse?

There are several reasons why a plastic container with chemical formulations inside could collapse.

  1. Internal pressure: Some chemical formulations release gases or generate pressure variations within the container itself due to chemical reactions, but the internal pressure can also be altered by external factors such as temperature, atmospheric pressure, or improper handling of the container. If the container is not strong enough to withstand this pressure, it can collapse.
  2. Chemical reaction with the plastic material of the container: Certain chemical formulations can react with the plastic material of the container, weakening its structure and causing it to collapse.
  3. Temperature: Certain chemical formulations may be sensitive to temperature changes. If the container cannot withstand high or low temperatures, it may collapse when exposed to them.
  4. Wear or damage to the container: If the container has cracks, deformations or damage to its structure, it could collapse when a variation in internal pressure is generated due to the reactions of the chemical formulation.


Keep reading: How to ensure the preservation of the agrochemical


Paneling in a plastic container: What factors cause the paneling of a package and how to avoid it?

Some of the factors that can cause paneling are the following:

  1. Pressure of the contents: If the container is filled with a product with high internal pressure, or that can generate gas inside, the force of the contents can deform the walls of the container.
  2. Packaging design: The design and construction of the packaging can be an important factor. If the material used is weak or does not have adequate structural strength, paneling is more likely to occur.
  3. Improper handling: If the container is subjected to shocks, excessive stacking or irregular pressure during storage or transport, it can lead to deformation of the walls of the container.

However, to avoid paneling a container, we recommend selecting the right plastic container. Use packaging with the optimal structural composition (monolayer or with co-extruded barrier layer or plasma fluorination) and weight, of quality and resistance, which is capable of withstanding the external forces to which it will be subjected during its shelf life, as well as internal pressures due to possible alterations and internal reactions of the packaged formulation.

In addition, correct handling must be carried out, ensuring that the containers are handled correctly, avoiding bumps, excessive stacking or irregular pressures, and using appropriate packaging or palletizing systems to protect the containers during transport and storage.

On our side, from the point of view of the construction and design of our plastic packaging, APS takes into account:

  1. Structural reinforcement: We design the container with structural reinforcements, such as internal ribs, reinforcements at corners or at points of greatest stress, to increase its resistance and prevent deformation.
  2. Resistance tests and analyses: We carry out resistance tests and analyses to determine the capabilities of the packaging against different external forces by adjusting its design accordingly.

By following these measures, the likelihood of paneling on packaging can be minimized, ensuring product integrity and consumer satisfaction.

In short, a plastic container containing chemical formulations can collapse due to the internal pressure generated, the chemical reaction with the plastic, changes in temperature or external pressure, or damage to the structure of the container. It is important to use suitable and resistant packaging to store and transport these types of chemical formulations, which generally require approval according to ADR (European Agreement on the International Carriage of Dangerous Goods by Road) and marked with their respective identification number.


Compatibility testing packaging vs Packaged product

How to perform product packaging compatibility tests for packaging chemicals

Carrying out packaging-product compatibility tests for packaging chemicals is important in order to ensure that the packaging and the chemical are compatible and that there are no negative interactions that could compromise the quality of the packaged product or the safety of the user.

From APS we recommend our customers to carry out the following steps to check the compatibility of the product with the packaging seen as a set (container + cap):

  1. Select containers by choosing different types of packaging that are commonly used to store these products, such as HDPE bottles of various weights and plastic containers with barrier layers, either co-extruded or with a plasma-generated chemical barrier. The sensitivity of some plastic materials to certain components of the formulation must be taken into account, as, for example, PA (Polyamide) is sensitive to water.
  2. Also select the most suitable type of cap, since, if it is presumed that the formulation to be packaged can react inside the container and generate gases, these must be recirculated or even be able to be evacuated to the outside by means of the most appropriate closure system.

APS has a specific department that is responsible for supplying small series of its containers and/or caps duly identified so that our customers can carry out the relevant tests.

  1. Our client, on the other hand, must prepare the samples of the formulation, filling and storage in the supplied containers, controlling the parameters of their product, making periodic observations at predefined intervals to evaluate possible changes in the packaging or in the stored product. Some of the aspects to look out for include leaks, warping, changes in color or texture, and any other signs of spoilage of the packaging. At the same time, keep a record of the results of the observations made, including any changes or deterioration observed in the packaging or in the stored product.
  2. Analysis and interpretation: Analyze the results recorded together with the PHC team in order to make a correct interpretation of them. If changes or deterioration are observed in the packaging or the product, there may be some kind of incompatibility between the two. In such a case, further research should be done and consideration should be given to changing parameters of the type of cap type used.

It is important to note that these packaging-product compatibility tests are only one part of the evaluation of the safety and quality of the packaging for the storage of chemicals. Other aspects, such as local regulations and labeling requirements, must also be taken into account to ensure the proper storage and handling of these chemicals. For this reason, we always recommend consulting the regulations and recommendations of the country where the product is going to be marketed beforehand.

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How to know that a plastic container complies with ADR and legislation for the transport of dangerous goods

In general, the transport and handling of these chemicals normally requires compliance with the ADR (European Agreement on the International Carriage of Dangerous Goods by Road). To determine if a plastic container complies with ADR and the legislation for the transport of dangerous goods, at APS we verify that it complies with characteristics such as:

  1. Resistance conditions: The container must be able to withstand the conditions of transport and handling without suffering damage that could compromise its integrity and the safety of the cargo.
  2. Airtightness: The container must be able to safely and watertightly contain the hazardous substance during transport, preventing leaks or spills.

In addition, we provide our customers with information on the materials used in their manufacture and their resistance to hazardous substances, as well as the temperature and pressure limits to which they may be subjected.


Keep reading: Product Counterfeiting – APS Solutions


Based on all the tests and parameters tested, the packaging will be certified according to ADR (UN mark) by an authorized body to ensure that it complies with the safety standards established by current legislation.

In case of doubt, it is advisable to consult the specific regulations of each country and, in the case of international transport, the ADR, for precise and up-to-date information on the requirements that plastic packaging must meet for the transport of dangerous goods.


What information is contained on the license plate of an ADR-certified plastic container?

The registration number of a plastic container certified according to ADR (European Agreement on the International Carriage of Dangerous Goods by Road) contains the following information:


An UN symbol followed by a nomenclature that indicates:

  1. Type of packaging (jerrycan, jerrycan…)
  2. Material (plastic…)
  3. Category 1 or 2 depending on your fixed or movable lid
  4. Packaging group (I,II,III depending on the hazard of the packaged product)
  5. Density
  6. Hydraulic Pressure Test
  7. Year of manufacture
  8. Country of Manufacture
  9. Approval number: This is a unique code assigned to the certified packaging, indicating that it meets the requirements and is authorized for the transport of dangerous goods.
  10. Manufacturer’s Identification

Marking example:

UN 3H1/Y1.4/140/23/E/J-10033/APS

This marking means the following, as explained:


  • Packaging regulated according to United Nations international standards
  • 3H1 Container Type (Jerrican or Fixed Lid Plastic Bucket)
  • Y Packing Groups II & lll
  • 1.4 Maximum density of the product to be conveyed in gr/cm3
  • 140 Test Gauge Pressure in KPa*
  • 23 Year of manufacture.
  • E Country granting approval (Spain)
  • J-10033 Approval or registration number
  • APS Manufacturer’s Anagram


Do you need more information? Contact us!