This article introduces a new technology for producing high oxygen barrier BOPET films. The film consists of a BOPET base film with a PVA coating on one side. The crystallinity of the PVA coating is 60% to 80%, and the orientation degree is 10% to 15%. This production method adds a coating step between the longitudinal and transverse stretching processes in the BOPET film production process.
1. Why high oxygen resistance BOPET film is needed
This is mainly used in fields such as food and pharmaceutical packaging. Because they need films with good barrier properties. This ensures safe long-term storage.
Existing PVA materials use an offline method to prepare barrier films. This method is complex and inefficient.
2. How to produce
To solve these problems, a new method for producing high oxygen barrier BOPET films was proposed.
This method is to add a PVA coating to one side of the BOPET base film during the production process. But there are specific crystallinity and orientation requirements for PVA coatings.
3. Technical realization
The process begins with resin slicing, followed by squeeze casting.
In the production process of BOPET films, a coating step is added between the longitudinal and transverse stretching processes. It applies PVA coating to one side of the film.
The coating liquid used for online coating consists of 12 to 15 parts of PVA17-99, 6 to 8 parts of plasticizer, 4 to 5 parts of OMMT, 2 to 3 parts of defoaming agent, and 3 to 5 parts of aminoformaldehyde resin cross-linking agent, and 64 to 73 parts deionized water.
The oxygen transmission rate of the obtained high oxygen barrier BOPET film is 0.65 to 0.75 cm3/m²·24hr·atm (23°C). The water vapor transmission rate is 5 to 10 g/m²·24hr·atm (23°C).
The development of high oxygen barrier BOPET films and their production methods represents a major advancement in packaging technology. This innovation is achieved by improving barrier properties and production efficiency. This meets the growing demand for safe and reliable packaging solutions.
