D21C 9/00
After-treatment of cellulose pulp
Official title: After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters {; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere (polysaccharides, derivatives thereof C08B; paper-making D21B - D21H)}
D21C9/00 (After-treatment of cellulose pulp) appears on 2,450 US grants and 2,031 published applications in this corpus.
Search patents in D21C- Granted patents
- 2,450
- Published applications
- 2,031
- Assignees
- 952
- Inventors
- 4,362
- Latest grant
- 6 Oct 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 27 | 0 |
| 1977 | 26 | 0 |
| 1978 | 32 | 0 |
| 1979 | 14 | 0 |
| 1980 | 27 | 0 |
| 1981 | 40 | 0 |
| 1982 | 15 | 0 |
| 1983 | 30 | 0 |
| 1984 | 40 | 0 |
| 1985 | 35 | 0 |
| 1986 | 26 | 0 |
| 1987 | 22 | 0 |
| 1988 | 33 | 0 |
| 1989 | 41 | 0 |
| 1990 | 33 | 0 |
| 1991 | 43 | 0 |
| 1992 | 41 | 0 |
| 1993 | 43 | 0 |
| 1994 | 48 | 0 |
| 1995 | 64 | 0 |
| 1996 | 62 | 0 |
| 1997 | 77 | 0 |
| 1998 | 67 | 0 |
| 1999 | 63 | 0 |
| 2000 | 76 | 0 |
| 2001 | 83 | 24 |
| 2002 | 66 | 76 |
| 2003 | 69 | 89 |
| 2004 | 54 | 84 |
| 2005 | 28 | 82 |
| 2006 | 45 | 68 |
| 2007 | 40 | 48 |
| 2008 | 23 | 72 |
| 2009 | 23 | 65 |
| 2010 | 30 | 77 |
| 2011 | 49 | 64 |
| 2012 | 52 | 75 |
| 2013 | 55 | 87 |
| 2014 | 85 | 97 |
| 2015 | 54 | 107 |
| 2016 | 62 | 96 |
| 2017 | 59 | 98 |
| 2018 | 57 | 84 |
| 2019 | 69 | 86 |
| 2020 | 76 | 102 |
| 2021 | 66 | 104 |
| 2022 | 60 | 97 |
| 2023 | 52 | 85 |
| 2024 | 82 | 61 |
| 2025 | 59 | 63 |
| 2026 | 27 | 40 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Method for fractionation of highly refined cellulose6 Oct 2026US 12,753,551 B2Stora Enso OYJ
- Moisture/oil resistant composite materials29 Sep 2026US 12,747,536 B2World Centric
- Multi-ply liner with washed NSSC pulp29 Sep 2026US 12,747,539 B2Stora Enso OYJ
- Method for producing a transfer mixture by the direct dissolution process, using a thin layer evaporator15 Sep 2026US 12,735,840 B2List Technology AG
- Method of controlling the drying of cellulose pulp in a drying step of a pulp production process15 Sep 2026US 12,735,841 B2Andritz Technology and Asset Management GmbH
- Process for producing hygienized pulp8 Oct 2026US 2026/0308846 A1Kemira Oyj
- Cellulose-containing compositions, methods for their preparation, and uses comprising them3 Sep 2026US 2026/0258604 A1Renmatix, Inc.
- Process for producing a fibrous material27 Aug 2026US 2026/0250912 A1Stora Enso OYJ
- Process for producing rigid cellulosic product20 Aug 2026US 2026/0243023 A1Honext Material, Sl
- Pulp mixture6 Aug 2026US 2026/0226680 A1SöDra SkogsäGarna Ekonomisk FöRening
Most cited
By later US patents
- Absorbent structure containing individualized, polycarboxylic acid crosslinked wood pulp cellulose fibers694US 5,137,537 AThe Procter & Gamble Cellulose Company · 1992
- Individualized cellulosic fibers crosslinked with polyacrylic acid polymers185US 5,549,791 AThe Procter & Gamble Company · 1996
- Process for preparing individualized, polycarboxylic acid crosslinked fibers178US 5,190,563 AThe Proctor & Gamble Company · 1993
- Processing biomass176US 7,932,065 B2Xyleco, Inc. · 2011
- Absorbent articles with nits and free-flowing particles154US 6,667,424 B1Kimberly-Clark Worldwide, Inc. · 2003