- All sections
- D - Textilespaper
- D21C - Production of cellulose by removing non-cellulose substances from cellulose- containing materialsregeneration of pulping liquorsapparatus therefor
- D21C 3/20 - Pulping cellulose-containing materials with organic solvents
Patent holdings for IPC class D21C 3/20
Total number of patents in this class: 240
10-year publication summary
|
25
|
10
|
13
|
17
|
11
|
23
|
31
|
7
|
11
|
11
|
| 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
Principal owners for this class
| Owner |
All patents
|
This class
|
|---|---|---|
| GranBio Intellectual Property Holdings, LLC | 119 |
24 |
| API Intellectual Property Holdings, LLC | 77 |
9 |
| E. I. du Pont de Nemours and Company | 4086 |
8 |
| The Regents of the University of California | 19898 |
7 |
| Canfor Pulp Ltd. | 16 |
5 |
| Licella Pty Limited | 28 |
5 |
| National Technology & Engineering Solutions of Sandia, LLC | 1899 |
5 |
| Pierson Capital Environmental (Beijing) Limited | 10 |
5 |
| Shell Oil Company | 2141 |
4 |
| Buckman Laboratories International, Inc. | 237 |
4 |
| IFP Energies Nouvelles | 2945 |
4 |
| Stora Enso Oyj | 1636 |
4 |
| Shell Internationale Research Maatschappij B.V. | 3542 |
3 |
| Annikki GmbH | 73 |
3 |
| Celanese International Corporation | 907 |
3 |
| Chemstone, Inc. | 24 |
3 |
| Evrnu, SPC | 16 |
3 |
| Nalco Company | 563 |
3 |
| Nederlandse Organisatie voor Toegepast-natuurwetenschappelijk Onderzoek TNO | 2377 |
3 |
| Politecnico di Milano | 847 |
3 |
| Other owners | 132 |