B01D 2239/0435
Electret
B01D2239/0435 (Electret) appears on 254 US grants and 392 published applications in this corpus.
Search patents in B01D- Granted patents
- 254
- Published applications
- 392
- Assignees
- 175
- Inventors
- 801
- Latest grant
- 11 Aug 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1979 | 1 | 0 |
| 1980 | 1 | 0 |
| 1981 | 0 | 0 |
| 1982 | 1 | 0 |
| 1983 | 1 | 0 |
| 1984 | 0 | 0 |
| 1985 | 1 | 0 |
| 1986 | 3 | 0 |
| 1987 | 0 | 0 |
| 1988 | 2 | 0 |
| 1989 | 2 | 0 |
| 1990 | 3 | 0 |
| 1991 | 2 | 0 |
| 1992 | 1 | 0 |
| 1993 | 4 | 0 |
| 1994 | 3 | 0 |
| 1995 | 8 | 0 |
| 1996 | 5 | 0 |
| 1997 | 11 | 0 |
| 1998 | 7 | 0 |
| 1999 | 11 | 0 |
| 2000 | 7 | 0 |
| 2001 | 10 | 2 |
| 2002 | 0 | 2 |
| 2003 | 2 | 3 |
| 2004 | 5 | 4 |
| 2005 | 2 | 3 |
| 2006 | 1 | 5 |
| 2007 | 0 | 2 |
| 2008 | 2 | 6 |
| 2009 | 1 | 4 |
| 2010 | 3 | 8 |
| 2011 | 5 | 7 |
| 2012 | 3 | 7 |
| 2013 | 3 | 4 |
| 2014 | 4 | 3 |
| 2015 | 3 | 12 |
| 2016 | 4 | 10 |
| 2017 | 6 | 16 |
| 2018 | 7 | 14 |
| 2019 | 17 | 20 |
| 2020 | 10 | 18 |
| 2021 | 11 | 45 |
| 2022 | 13 | 49 |
| 2023 | 10 | 72 |
| 2024 | 20 | 27 |
| 2025 | 25 | 27 |
| 2026 | 13 | 22 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Biodegradable filters11 Aug 2026US 12,702,942 B2NxtNano, LLC
- Multifunctional filter materials30 Jun 2026US 12,667,143 B2Khalifa University of Science and Technology
- Polypropylene composition containing a new charge-stabilizing agent for electret melt blown webs2 Jun 2026US 12,643,990 B2Borealis AG
- Filter media, composites, and face mask systems using same26 May 2026US 12,636,524 B2Donaldson Company, Inc.
- Electret and filter using the same28 Apr 2026US 12,611,650 B2TOYOBO MC Corporation
- Multifunctional filter materials8 Oct 2026US 2026/0305741 A1Khalifa University of Science and Technology
- Graphene Functionalized HEPA Filter23 Jul 2026US 2026/0208085 A1University of Connecticut
- Passive sensor capable of detection of materials including specific dna or dna-like strands16 Jul 2026US 2026/0201448 A1Dna Profile Ltd.
- Shirred filter media and methods of making and using the same9 Jul 2026US 2026/0192220 A13M Innovative Properties Company
- Spun-bonded nonwoven fabric, filter medium, air filter, and apparatus for producing filter medium4 Jun 2026US 2026/0152885 A1Toray Industries, Inc.
Most cited
By later US patents
- Melt-blown fibrous electrets387US 4,215,682 AMinnesota Mining and Manufacturing Company · 1980
- Method of charging electret filter media289US 5,496,507 AMinnesota Mining and Manufacturing Company · 1996
- Method for manufacturing an electret filter medium243US 4,588,537 AMinnesota Mining and Manufacturing Company · 1986
- Method of making fibrous electrets241US 4,375,718 ASurgikos, Inc. · 1983
- Method of manufacturing an electret filter230US 4,592,815 AJapan Vilene Company, Ltd. · 1986