Sulfite-based processes for producing nanocellulose, and compositions and products produced therefrom
US-2025257527-A1 · Aug 14, 2025 · US
sulfur dioxide; sulfurous acid; bisulfites {sulfites}
sulfur dioxide; sulfurous acid; bisulfites {sulfites} · Cooperative Patent Classification (CPC)
Textile and paper production, treatment, and products.
Related technology areas
Mapped technology topics for this CPC code.
| Metric | Value |
|---|---|
| CPC code | D21C3/06 |
| Official title | sulfur dioxide; sulfurous acid; bisulfites {sulfites} |
| Display label | sulfur dioxide; sulfurous acid; bisulfites {sulfites} |
| Total patents | 64 |
Filing trend
Year-over-year patent counts classified under this CPC code.
Filing activity over the last five years is declining.
| Year | Patents |
|---|---|
| 2015 | 8 |
| 2016 | 11 |
| 2017 | 5 |
| 2018 | 7 |
| 2019 | 5 |
| 2020 | 2 |
| 2021 | 9 |
| 2022 | 5 |
| 2023 | 1 |
| 2024 | 6 |
| 2025 | 5 |
Representative patents
Representative publications under this CPC code from precomputed stats, or recent filings when stats are unavailable.
Common preparation of lignocellulosic feedstock and a product containing cellulose but free from lignin
US-12116729-B2 · Oct 15, 2024 · US
Pickering emulsion stabilized by cellulose nanocrystals from ginkgo seed shells and preparation method thereof
US-12115221-B2 · Oct 15, 2024 · US
Processes for producing nanocellulose, and nanocellulose compositions produced therefrom
US-12091818-B2 · Sep 17, 2024 · US
Nanocellulose production co-located at a pulp and paper mill
US-12077910-B2 · Sep 3, 2024 · US
Processes and apparatus for producing nanocellulose, and compositions and products produced therefrom
US-2024247081-A1 · Jul 25, 2024 · US
Processes and apparatus for producing nanocellulose, and compositions and products produced therefrom
US-11932706-B2 · Mar 19, 2024 · US
Nanolignocellulose compositions and processes to produce these compositions
US-11834523-B2 · Dec 5, 2023 · US
Common preparation of lignocellulosic feedstock and a product containing cellulose but free from lignin
US-2022243399-A1 · Aug 4, 2022 · US
Pretreatment with lignosulfonic acid
US-11312977-B2 · Apr 26, 2022 · US
Converting lignocellulosic biomass to glucose using a low temperature sulfur dioxide pretreatment
US-11299850-B2 · Apr 12, 2022 · US
Sulfite-based processes for producing nanocellulose, and compositions and products produced therefrom
US-2022034038-A1 · Feb 3, 2022 · US
Pretreatment of softwood
US-2022017928-A1 · Jan 20, 2022 · US
Nanocellulose production co-located at a pulp and paper mill
US-2021340706-A1 · Nov 4, 2021 · US
Processes and apparatus for producing nanocellulose, and compositions and products produced therefrom
US-2021284757-A1 · Sep 16, 2021 · US
Processes for producing nanocellulose, and nanocellulose compositions produced therefrom
US-2021277151-A1 · Sep 9, 2021 · US
Nanolignocellulose compositions and processes to produce these compositions
US-2021221919-A1 · Jul 22, 2021 · US
Pickering emulsion stabilized by cellulose nanocrystals from ginkgo seed shells and preparation method thereof
US-2021213405-A1 · Jul 15, 2021 · US
Sulfur dioxide and/or sulfurous acid pretreatment with sulfur dioxide recovery
US-10995314-B2 · May 4, 2021 · US
Drying/transportation and releasing MFC
US-10947670-B2 · Mar 16, 2021 · US
Frequently asked questions
Answers are generated from the same data shown on this page.
- What is CPC D21C3/06?
- CPC D21C3/06 is the Cooperative Patent Classification code for “sulfur dioxide; sulfurous acid; bisulfites {sulfites}.”
- How many patents are filed under CPC D21C3/06 (sulfur dioxide; sulfurous acid; bisulfites {sulfites})?
- Our database includes 64 publications tagged with this CPC code.
- Is patent activity under CPC D21C3/06 growing?
- Publication counts under this code: 6 in 2024 vs 5 in 2025 (latest complete years).