“The simple structure of a single-layer film is directly influenced by the properties of the resin used, making its strengths and weaknesses very apparent in the final product. On the other hand, multi-layer films such as Mitsubishi Chemical’s DIAMIRON™ layer multiple resins which enables the creation of high value-added films by leveraging the advantages of the respective materials while compensating for their disadvantages.” (Mr. Okada)

“Clients consulted us saying that, once the package is opened, the contents dry out, and using plastic wrap to preserve them takes time and effort, so there was a need for something that could be repeatedly opened and resealed. That was when we started to investigate applying resealability. Recently we have been receiving an increasing number of requests for DIAMIRON™ from the perspective of its potential to reduce plastic.” (Mr. Hanari)

“The design was very challenging. In particular, we had to find ways to make the first peel smooth so as to cleanly expose only the sticky layer of the multi-layer film when opening the sealed package, while also maintaining adhesive strength from the second time onwards” (Mr. Okada).

“The resin to be used in the resealable layer was a material our manufacturing division had never handled before. When we began processing it, we faced a significant challenge: maintaining a stable extrusion during the film-casting process.
Moreover, when we changed the overall film design, we encountered various problems during storage such as the film layers sticking to each other, and the appearance becoming slightly cloudy.
There was no choice but to overcome each of these problems one at a time while having repeated discussions with our customers.” (Mr. Hirano)

“I believe that the driving force behind speedily developing an optimal film that met customer needs is the close information sharing between the sales, R&D and manufacturing divisions. For example, if issues and problems are discovered during the manufacturing process, the R&D team makes suggestions about what film would be best to change, and how to change the raw material formulation. Then conversely, if there is a technology that the R&D team wants to try out, the manufacturing team responds to that flexibly.
And then, sales carefully collect client requests and give us detailed feedback. I believe that all of this accelerated development allowed us to achieve the resealability that the customer requested.” (Mr. Hirano)

“While sausage and ham are the main applications at the moment, we anticipate growing demand for resealable packaging in a variety of fields. Our future development will focus on addressing new challenges, such as preventing film from fogging in high-moisture products and thinning the current 60μm standard to support plastic waste reduction. We will continue to develop and make improvements.” (Mr. Okada)

“For the manufacturing division, waste reduction is a major challenge, and we will continue to engage with it. We want to further refine our manufacturing technology so we can respond quickly to proposals from the R&D side for a new raw material.” (Mr. Hirano)

“It is likely that there are no examples of using resealable film for a yoghurt lid anywhere in the world. I do believe that this is something we cannot achieve without the cooperation of food manufacturers and product end users, but I want to see a world in 10 years’ time where people can say, ‘Resealable films are the norm, right?’ This will also contribute to reduced plastic use, and I believe it is the very embodiment of Mitsubishi Chemical's KAITEKI.” (Mr. Hanari)