When it comes to retail packaging, clamshell packaging has the fastest growth rate of clear thermoformed packaging and has become one of the most recognized types of thermoformed package.
With the majority of clamshell packaging produced in ultra-clear PVC or PET material, customers are offered the best “billboard” for their product. The display and presentation of the product that clamshell packaging provides lends an added feature that other packages simply cannot match.
When looking at the design considerations for a clamshell, package designers must take into account a number of different aspects in order to create the right package.
The different components of clamshell packaging that need to be considered are the hinges, the flanges, the formed closing mechanism, and the product location within the package.
The hinge is typically the most critical part of the design process because it is affected by length, style, material distribution in the hinge area, and whether it is a male or female part.
Flanges are important because once the part is thermoformed, there needs to be an area for secondary sealing, or an area in which a consumer would be able to pull open the package.
The formed closing mechanism is based mostly on the customer’s information. Changes are made through prototyping and during the initial inspection run; however, the overall goal is to get a tight fit based on the customer’s requirements.
The location of the product within the thermoformed clamshell package is similarly very important when creating a design. Details such as front-to-back location within the package, displayability, hangability, and side-to-side location all dictate how a thermoformed package will be designed.
Material distribution is determined by plugs and process sequence.
Process sequence would be vacuum, form air, tool temperature, and the timing of all of those three. Undercuts make the parts difficult to remove from the tool, to de-nest from each other, and to process parts on a heat sealer. Plug design based on the material being used and the geometry of the part and tooling is also a critical component to ensuring appropriate material distribution on thermoformed parts.
Advantages and Disadvantages
- Customer only has to buy one tool
- Assembly line must have the necessary space for a clamshell lid
- Package security may require a secondary seal