D21C 9/1026
Other features in bleaching processes
Official title: {Other features in bleaching processes}
D21C9/1026 (Other features in bleaching processes) appears on 355 US grants and 234 published applications in this corpus.
Search patents in D21C- Granted patents
- 355
- Published applications
- 234
- Assignees
- 232
- Inventors
- 858
- Latest grant
- 1 Sep 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 11 | 0 |
| 1977 | 7 | 0 |
| 1978 | 4 | 0 |
| 1979 | 2 | 0 |
| 1980 | 6 | 0 |
| 1981 | 9 | 0 |
| 1982 | 2 | 0 |
| 1983 | 6 | 0 |
| 1984 | 5 | 0 |
| 1985 | 7 | 0 |
| 1986 | 2 | 0 |
| 1987 | 2 | 0 |
| 1988 | 3 | 0 |
| 1989 | 4 | 0 |
| 1990 | 3 | 0 |
| 1991 | 6 | 0 |
| 1992 | 7 | 0 |
| 1993 | 7 | 0 |
| 1994 | 7 | 0 |
| 1995 | 7 | 0 |
| 1996 | 7 | 0 |
| 1997 | 13 | 0 |
| 1998 | 10 | 0 |
| 1999 | 12 | 0 |
| 2000 | 27 | 0 |
| 2001 | 23 | 7 |
| 2002 | 11 | 12 |
| 2003 | 10 | 12 |
| 2004 | 11 | 9 |
| 2005 | 2 | 11 |
| 2006 | 5 | 12 |
| 2007 | 6 | 9 |
| 2008 | 5 | 9 |
| 2009 | 4 | 16 |
| 2010 | 5 | 14 |
| 2011 | 6 | 13 |
| 2012 | 10 | 10 |
| 2013 | 9 | 15 |
| 2014 | 14 | 10 |
| 2015 | 6 | 6 |
| 2016 | 3 | 7 |
| 2017 | 5 | 8 |
| 2018 | 8 | 9 |
| 2019 | 4 | 7 |
| 2020 | 6 | 8 |
| 2021 | 8 | 6 |
| 2022 | 4 | 4 |
| 2023 | 5 | 9 |
| 2024 | 1 | 4 |
| 2025 | 5 | 2 |
| 2026 | 3 | 5 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Method for distributing chemicals in delignification stages of pulp bleaching process1 Sep 2026US 12,723,350 B2Andritz Inc.
- Xylanase variants14 Apr 2026US 12,600,960 B2AB Enzymes Finland Oy
- Process and apparatus for producing bleached cellulose24 Feb 2026US 12,559,885 B2Messer Austria GmbH
- Process to optimize brown stock washing unit operations23 Dec 2025US 12,503,814 B2Ecolab USA Inc.
- Preparation of cellulose fibers21 Oct 2025US 12,448,730 B2Jena Trading Aps
- Chemical wood pulp with enhanced tensile strength6 Aug 2026US 2026/0226685 A1SöDra SkogsäGarna Ekonomisk FöRening
- Carboxymethylated lysine-based polymer and compositions comprising the same16 Jul 2026US 2026/0201119 A1BASF SE
- Method for bleaching cellulose pulp formed from recycled textile material9 Jul 2026US 2026/0193838 A1Valmet Corporation
- Rinsing device for refined cotton29 Jan 2026US 2026/0028772 A1Hubei Jinhanjiang Refined Cotton Co., Ltd.
- Producing nanofibers, microfibers, and lignin from lignocellulosic biomass22 Jan 2026US 2026/0022519 A1University of Washington
Most cited
By later US patents
- Method for the alkaline bleaching of pulp with a peroxyacid based oxygen bleaching species using an agglomerated bleach activator89US 6,569,286 B1Warwick International Group Limited · 2003
- Alkaline peroxide mechanical pulping of non-woody species86US 6,258,207 B1Alberta Research Council · 2001
- Multi-stage bleaching process including an enhanced oxidative extraction stage77US 4,568,420 AInternational Paper Company · 1986
- Method for using an all solid-state fluorometer in industrial water system applications77US 6,255,118 B1Nalco Chemical Company · 2001
- Use of glycine-N,N-diacetic acid derivatives as biodegradable complexing agents for alkaline earth metal ions and heavy metal ions and process for the preparation thereof59US 5,786,313 ABASF SE · 1998