BOPET and Polyester Films Patents: Top Companies & Trends 2026
- 62.8% concentration. The top 5 assignees hold 206 of 328 records in scope, so most of the claim space around thickness uniformity, coating adhesion and hydrolytic stability is already occupied by a small group.
- Filing has flattened, not grown. Volume peaked at 20 records in 2017; the 2022 midpoint sits at 15, and the trend has not recovered since, even allowing for publication lag on the most recent years.
- Processing dominates the IPC mix. C08J (polymer processing) and B29C (shaping of plastics) each cover more than two-thirds of the 328 records, while B29D (specific plastic articles) sits at just 14.6% — the smallest of the eight tracked classes.
What the BOPET and polyester film patent record actually shows
Biaxially oriented PET film sits at the intersection of bulk polymer processing and specialised end-use requirements — thickness uniformity, surface treatment for coating adhesion, hydrolytic stability for PV backsheets, and optical film substrate grade control are the claim anchors this search was built around. The 328 records in scope span 2015 through the 2026 data cut-off, filed under IPC classes covering polymer processing (C08J), plastics shaping (B29C) and condensation polymer chemistry (C08G).
Filing activity is not evenly spread. A small set of assignees accounts for most of the volume, receiving-office activity clusters around Europe, Japan, Korea and the United States, and the most-cited records in the set date back to the 1980s and 1990s film-forming patents that still anchor prior art searches today.
Filing trend and technology composition
Two views of the same 328 records: how filing volume has moved year over year, and how the record set breaks down across IPC subclasses. Because a single record can carry several IPC codes, the composition shares add up to more than 100%.
A peak in 2017, no clear recovery since
Filings hit their tracked high of 20 in 2017 and had fallen back to 15 by the 2022 midpoint. The line does not show a rebound afterward — read the final one to two years as understated, since publication typically lags filing by around 18 months, but the multi-year plateau through the middle of the window is a real signal, not an artefact of lag.
Processing classes carry the bulk of the filing weight
C08J (polymer processing and solutions) touches 78.0% of the 328 records and B29C (shaping of plastics) touches 66.5%, confirming that most claims in this set are process- and formation-focused rather than end-article-specific. B29D (specific plastic articles), the narrowest tracked class at 14.6%, is the closest thing to a gap in the composition, though it is still tens of records deep rather than empty.
Shares are the percentage of the 328 records in scope. A patent can carry several IPC classes, so the shares add up to more than 100%.
Go deeper on BOPET and Polyester Films with Eureka
This page is one run against one query. Ask Eureka your own question about bopet and polyester films and every answer comes back with the patent numbers behind it.
Try EurekaThe patents still shaping freedom-to-operate
Thermo-shrinkable polyester film (US20100331513A1)
Discloses a thermo-shrinkable polyester film with strength of 3.5-6.5 kg/mm2 perpendicular to the main shrinking direction at under 10% initial elongation, elongation at rupture of 50-700% in that same direction, thickness uniformity (ΔR) of 4 or less, and shrinkage ratio of 5% or less — combining process stability with resistance to rupture during rolling.Filed by Microworks Co., Ltd., published 2010-12-30.
| # | Publication no. | Patent title | Citations |
|---|---|---|---|
| 1 | JP1984005216B2 | Polyester film | 101 |
| 2 | US5429785A | Method of making biaxially oriented thermoplastic films | 72 |
| 3 | GB2134442A | Polyester film for magnetic recording media | 53 |
| 4 | US5409657A | Process for making oriented semicrystalline polyester films | 51 |
| 5 | US4677188A | Transparent slippery biaxially stretched polyester film | 45 |
| 6 | JP1990180933A | White surface-roughened polyester film and its production | 33 |
| 7 | US20040028925A1 | Biaxially oriented polyester film | 28 |
| 8 | US20050239929A1 | Polyester resin compositions, catalyst for polyester production, polyester film, and magnetic recording medium | 27 |
| 9 | JP1990163155A | Polyester film | 24 |
| 10 | US6048626A | Polyester composition and film made therefrom | 23 |
Citation counts inside a searched corpus favour older filings — treat this table as a map of influential prior art, not a ranking of current relevance.
Each row carries its publication number; clicking a row searches Eureka by that number.
Put your own technology through the same analysis
Eureka on the web
When you want the answer in the next five minutes.
The agent works the prompt against patents and technical literature, citing every source.
Run your analysis now →MCP server & REST API
When it has to run inside your own pipeline.
Patent search, landscape analysis and assignee resolution as MCP tools. Drop them into any agent framework, or call REST directly.
Browse MCP servers →What the pattern means for a filing decision
Three read-outs from the concentration, trend and citation data that matter more than the raw counts on their own.
The top of the field is dense, not open
With 206 of 328 records held by five assignees, new entrants filing broad claims on core BOPET processing or surface-treatment steps are filing into territory that is already crowded. Differentiated claims — specific additive chemistries, narrow process windows, or application-specific film grades — have more room than general film-forming claims.
Growth has stalled since the 2017 peak
The filing trend peaked at 20 records in 2017 and had eased to 15 by 2022, with no recovery visible through the tracked window. Recent-year figures understate true activity because of publication lag, but the multi-year plateau predates that effect and points to a maturing rather than expanding claim space.
Old film-forming patents still anchor searches
The most-cited record in the set is a polyester film patent dating to the 1980s, followed by biaxial orientation and film-forming processes from the mid-1990s. Any new filing on core stretching or forming steps should expect examiners to cite this older body of art first.
Eureka can read the same corpus for gaps instead of for coverage: under-claimed branches adjacent to bopet and polyester films, with the prior art for and against each one.
Who holds the claim space, and where activity has gone quiet
The ranked leader holds 56 records; by fifth place that falls to 27, and by tenth place to 7 — a steep drop-off consistent with the 62.8% and 85.7% concentration figures for the top 5 and top 10 respectively.
One filer sets the pace
The leading assignee's record count is double that of the fifth-placed company, a gap wide enough that its claim scope is worth reviewing first in any freedom-to-operate check on core BOPET processing.
A workable second tier
Positions two through five hold enough volume individually to represent real competitive filing programmes rather than opportunistic single filings, and together with the leader they account for 206 of the 328 records in scope.
Even top filers show no latest-year activity
Several of the most active historical assignees show zero filings in the most recent tracked year. Given the roughly 18-month publication lag, this understates true activity, but it also means recent competitive moves by these firms are not yet visible in the public record.
| Assignee | Recent year | YoY |
|---|---|---|
| SKC Co., Ltd. | 0 | — |
| Toyobo Co., Ltd. | 0 | — |
| DIALFONE CO LTD | 0 | — |
| Toray Industries, Inc. | 0 | — |
| Teijin Limited | 0 | — |
| Unitika Ltd. | 0 | — |
| Kolon Industries, Inc. | 0 | — |
| FUJIFILM Corporation | 0 | — |
Where to take this analysis
The concentration and composition figures point to specific next questions rather than a general conclusion.
Check claim scope against the top 5
Before filing on core film-forming or surface-treatment steps, review the claim language of the top 5 assignees, who together hold 62.8% of the 328 records in scope.
Run a claim comparison in EurekaTest the under-claimed branches
Recycled-content substrates and PV-grade hydrolytic stability sit inside the tracked IPC classes but carry lower record density than core processing claims — worth a targeted search before assuming the space is open.
Explore white space in EurekaWatch for lagging disclosures
Several leading assignees show no latest-year filings in this dataset; given the typical 18-month publication lag, monitor these firms for filings that have not yet published.
Set up assignee monitoring in EurekaCommon questions on BOPET and polyester film patents
The ranked leader in this dataset holds 56 of the 328 records in scope, roughly double the count of the fifth-placed assignee at 27. The top 5 assignees combined hold 206 records, or 62.8% of the total, and the top 10 hold 85.7%. This is a concentrated field: most of the active claim space sits with a small number of established film producers rather than being spread across many independent filers.
Not clearly. Filing volume peaked at 20 records in 2017 and had eased to 15 by the 2022 midpoint, with no recovery visible through the rest of the tracked window. Recent years always look lower than they will eventually be, since publication typically lags filing by about 18 months, but the multi-year plateau through the middle of the period suggests a maturing rather than an expanding field.
Polymer processing (IPC class C08J) touches 78.0% of the 328 records and plastics shaping (B29C) touches 66.5%, making process- and formation-related claims the densest part of the field. Layered products and laminates (B32B) and polymer compositions (C08L) follow at lower shares. Specific plastic articles (B29D), at 14.6%, is the narrowest of the eight tracked classes and the closest thing to relative white space.
US20100331513A1, assigned to Microworks Co., Ltd. and published in December 2010, claims a thermo-shrinkable polyester film defined by specific mechanical and dimensional parameters: strength of 3.5 to 6.5 kg/mm2 perpendicular to the main shrinking direction, elongation at rupture of 50 to 700% in that direction, a thickness uniformity (ΔR) of 4 or less, and a shrinkage ratio of 5% or less. Anyone developing a thermo-shrinkable film with overlapping parameter ranges should review this claim set closely, since it is defined by numeric process windows rather than broad material composition.
Based on relative record density, recycled-content BOPET substrates, PV-grade hydrolytic stability, and low-migration surface treatments for coating adhesion carry fewer records than the dominant processing and shaping classes. These branches sit inside the existing IPC footprint of the field, so they are not unclaimed territory, but they are less crowded than core film-forming and stretching claims where 62.8% of records already concentrate among five assignees.
Research BOPET and Polyester Films in depth with Eureka
Go past this page: query the whole bopet and polyester films corpus yourself, in your own scope.
Every answer comes back with patent numbers you can open.
Disclaimer. This page is generated from Patsnap Eureka data drawn from a limited snapshot of global patent and scientific-literature records, and is provided for general information and reference only.
Patent data carries inherent limitations: recent filings (typically the most recent 18–24 months) are under-counted due to standard publication lag; counts may be reported at either a patent-family or a patent-record basis and are not always directly comparable; classification, applicant-name, and citation data may contain errors, duplicates, or omissions; and the underlying search query defines and constrains the scope shown. As a result, the analysis may be incomplete or inaccurate and may not reflect the full technology landscape.
Nothing on this page constitutes an exhaustive prior-art, novelty, freedom-to-operate, or validity search, nor does it constitute legal, financial, investment, or professional advice, and it should not be relied upon as such. Any patent, commercial, or strategic decision should be verified independently and reviewed with qualified patent, legal, and domain professionals. Patsnap makes no warranties, express or implied, as to the accuracy, completeness, or fitness for any particular purpose of the information presented.
Machine translation. Assignee and organisation names originally recorded in Chinese, Japanese or Korean have been rendered into English by an AI translation step so that the tables stay readable. These renderings are best-effort and may not match a company’s registered English name; the original name is what the underlying patent record carries, and it is what any Eureka query launched from this page uses.