- All sections
- D - Textilespaper
- D21C - Production of cellulose by removing non-cellulose substances from cellulose- containing materialsregeneration of pulping liquorsapparatus therefor
- D21C 3/06 - Pulping cellulose-containing materials with acids, acid salts, or acid anhydrides sulfur dioxidePulping cellulose-containing materials with acids, acid salts, or acid anhydrides sulfurous acidPulping cellulose-containing materials with acids, acid salts, or acid anhydrides bisulfites
Patent holdings for IPC class D21C 3/06
Total number of patents in this class: 124
10-year publication summary
|
10
|
7
|
7
|
2
|
24
|
20
|
6
|
7
|
12
|
3
|
| 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 | 2026 |
Principal owners for this class
| Owner |
All patents
|
This class
|
|---|---|---|
| GranBio Intellectual Property Holdings, LLC | 125 |
22 |
| SixRing Inc. | 178 |
22 |
| API Intellectual Property Holdings, LLC | 77 |
12 |
| Voith Patent GmbH | 2747 |
7 |
| Sekab E-Technology AB | 69 |
5 |
| Amppc Finland Oy | 5 |
5 |
| Billerud AB | 162 |
3 |
| Lenzing Aktiengesellschaft | 502 |
3 |
| BASF SE | 21308 |
2 |
| Shell Internationale Research Maatschappij B.V. | 3398 |
2 |
| Shell Oil Company | 2067 |
2 |
| Chemstone, Inc. | 26 |
2 |
| Imperial Innovations Limited | 548 |
2 |
| International Paper Company | 600 |
2 |
| Iogen Corporation | 160 |
2 |
| NORAM Engineering and Constructors Ltd. | 29 |
2 |
| Universidad Nacional Autonoma de Mexico | 144 |
2 |
| Valmet AB | 554 |
2 |
| Ip2ipo Innovations Limited | 170 |
2 |
| American Process International LLC | 5 |
2 |
| Other owners | 21 |