Cellulosic Barrier Structure for Recyclable Oxygen-Sealed Containers

The patent applies composite materials by combining cellulosic board substrate with polymer barrier films (such as EVOH, PVDC, or nylon) and metal oxide coatings (such as aluminum oxide, silicon oxide, or titanium oxide). This composite structure achieves high barrier performance against oxygen, moisture, and light penetration while maintaining recyclability, as the polymer and metal oxide layers can be separated from the cellulosic substrate during recycling processes, unlike traditional metallic barrier layers

The patent changes the material parameters by replacing metallic barrier layers with polymer-based barrier films and metal oxide coatings. Specifically, it uses polymers with inherent barrier properties (such as EVOH with oxygen transmission rate < 1 cc/m2/day) and applies metal oxide coatings through processes like atomic layer deposition (ALD) or plasma-enhanced chemical vapor deposition (PECVD) to achieve the desired barrier performance without compromising recyclability

The patent applies local quality by providing barrier protection only where needed - applying polymer barrier films and metal oxide coatings specifically on the inner surface of the cellulosic board substrate that contacts the packaged content. This localized approach ensures high barrier performance at the critical interface while maintaining the overall recyclability of the container structure

The patent uses polymer barrier films as intermediary layers between the cellulosic board substrate and the packaged content. These polymer intermediaries (such as EVOH or PVDC layers) provide the necessary barrier performance against oxygen, moisture, and light penetration, while their organic composition allows for better recyclability compared to metallic barrier layers. The metal oxide coatings serve as additional intermediary protective layers