Spun-bonded nonwoven fabric and air filter constituted from spun-bonded nonwoven fabric
US-2021283541-A1 · Sep 16, 2021 · US
Plant or installations without electricity supply, e.g. using electrets
Plant or installations without electricity supply, e.g. using electrets · Cooperative Patent Classification (CPC)
Separating, mixing, shaping, printing, and transporting materials.
Related technology areas
Mapped technology topics for this CPC code.
| Metric | Value |
|---|---|
| CPC code | B03C3/28 |
| Official title | Plant or installations without electricity supply, e.g. using electrets |
| Display label | Plant or installations without electricity supply, e.g. using electrets |
| Total patents | 110 |
Filing trend
Year-over-year patent counts classified under this CPC code.
Filing activity over the last five years is growing.
| Year | Patents |
|---|---|
| 2015 | 10 |
| 2016 | 7 |
| 2017 | 9 |
| 2018 | 11 |
| 2019 | 5 |
| 2020 | 9 |
| 2021 | 13 |
| 2022 | 15 |
| 2023 | 7 |
| 2024 | 6 |
| 2025 | 16 |
| 2026 | 2 |
Representative patents
Representative publications under this CPC code from precomputed stats, or recent filings when stats are unavailable.
Filter
US-11117140-B2 · Sep 14, 2021 · US
Imaging system, current control program for imaging system
US-2021271183-A1 · Sep 2, 2021 · US
Filter and air-conditioning device
US-2021268414-A1 · Sep 2, 2021 · US
Filter and air-conditioning device
US-11071933-B2 · Jul 27, 2021 · US
Electret-containing filter media
US-2021178304-A1 · Jun 17, 2021 · US
Image forming apparatus with particle collector
US-2021063962-A1 · Mar 4, 2021 · US
Multilayer filter material
US-2021046410-A1 · Feb 18, 2021 · US
Electretized sheet and filter
US-2021001255-A1 · Jan 7, 2021 · US
Electret-containing filter media
US-10814261-B2 · Oct 27, 2020 · US
Non-exhaust fine dust collecting device using triboelectricity
US-2020331005-A1 · Oct 22, 2020 · US
Charging fiber, charging filter, substance attracting material, and air purifier
US-2020292206-A1 · Sep 17, 2020 · US
Filter and air-conditioning device
US-2020282350-A1 · Sep 10, 2020 · US
Filter and air-conditioning device
US-10710011-B2 · Jul 14, 2020 · US
Window blinds that collect dust from air using electrostatic charge
US-10605000-B2 · Mar 31, 2020 · US
Filtration materials using fiber blends that contain strategically shaped fibers and/or charge control agents
US-10571137-B2 · Feb 25, 2020 · US
Remote fluorination of fibrous filter webs
US-2020023299-A1 · Jan 23, 2020 · US
Electret-treated sheet and filter
US-2020009489-A1 · Jan 9, 2020 · US
Filter
US-2019344288-A1 · Nov 14, 2019 · US
Filter and air-conditioning device
US-2019336895-A1 · Nov 7, 2019 · US
Frequently asked questions
Answers are generated from the same data shown on this page.
- What is CPC B03C3/28?
- CPC B03C3/28 is the Cooperative Patent Classification code for “Plant or installations without electricity supply, e.g. using electrets.”
- How many patents are filed under CPC B03C3/28 (Plant or installations without electricity supply, e.g. using electrets)?
- Our database includes 110 publications tagged with this CPC code.
- Is patent activity under CPC B03C3/28 growing?
- Publication counts under this code: 6 in 2024 vs 16 in 2025 (latest complete years).