In this dataset, high-barrier film refers to layered or coated polymer films engineered to resist gas and moisture transmission, typically claimed under IPC classes like B32B (layered products) and C08J (polymer processing). Many of the most-cited records combine a base polymer layer with a deposited or coated barrier layer, such as a vapor-deposited SiN layer or a polysilazane coating. The term spans both conventional packaging film and the encapsulation layers used in flexible electronics, which is why the IPC mix includes semiconductor and OLED classes alongside packaging ones.

The tracked filing trend peaked in 2017 at 5 families and dropped to a single family by the 2022 midpoint, with no rebound visible through the most recent years. This pattern is typical of a niche where the core chemistry and test-method claims were staked out early, leaving later filers to pursue narrower variations rather than foundational ones. It’s also worth treating the final one to two years of any trend chart as undercounted, since patent publication normally lags the actual filing date by around 18 months.

The most-cited record in this landscape is a 2006 filing on multilayer polymeric barrier film for flexible packaging, cited 169 times within this corpus. Two considerably older filings from the mid-1980s covering heat-sealable moisture-barrier film and bag constructions are each cited over 100 times, showing that foundational multilayer barrier chemistry from decades ago still anchors newer work. High citation counts favour older records simply because they’ve had more time to be cited, so they signal influence rather than current state-of-the-art status.