D21C 9/1057
Multistage, with compounds cited in more than one sub-group d21c9/10, d21c9/12, d21c9/16
Official title: {Multistage, with compounds cited in more than one sub-group D21C9/10, D21C9/12, D21C9/16}
D21C9/1057 (Multistage, with compounds cited in more than one sub-group d21c9/10, d21c9/12, d21c9/16) appears on 105 US grants and 62 published applications in this corpus.
Search patents in D21C- Granted patents
- 105
- Published applications
- 62
- Assignees
- 68
- Inventors
- 216
- Latest grant
- 24 Feb 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1980 | 1 | 0 |
| 1981 | 0 | 0 |
| 1982 | 0 | 0 |
| 1983 | 2 | 0 |
| 1984 | 2 | 0 |
| 1985 | 0 | 0 |
| 1986 | 1 | 0 |
| 1987 | 0 | 0 |
| 1988 | 1 | 0 |
| 1989 | 2 | 0 |
| 1990 | 2 | 0 |
| 1991 | 1 | 0 |
| 1992 | 6 | 0 |
| 1993 | 2 | 0 |
| 1994 | 5 | 0 |
| 1995 | 6 | 0 |
| 1996 | 6 | 0 |
| 1997 | 6 | 0 |
| 1998 | 5 | 0 |
| 1999 | 4 | 0 |
| 2000 | 8 | 0 |
| 2001 | 3 | 0 |
| 2002 | 3 | 1 |
| 2003 | 2 | 2 |
| 2004 | 1 | 7 |
| 2005 | 1 | 4 |
| 2006 | 1 | 4 |
| 2007 | 1 | 4 |
| 2008 | 1 | 2 |
| 2009 | 1 | 0 |
| 2010 | 0 | 0 |
| 2011 | 1 | 0 |
| 2012 | 1 | 2 |
| 2013 | 0 | 1 |
| 2014 | 3 | 2 |
| 2015 | 1 | 2 |
| 2016 | 1 | 2 |
| 2017 | 2 | 3 |
| 2018 | 3 | 7 |
| 2019 | 2 | 3 |
| 2020 | 3 | 2 |
| 2021 | 6 | 5 |
| 2022 | 1 | 1 |
| 2023 | 5 | 4 |
| 2024 | 0 | 0 |
| 2025 | 1 | 0 |
| 2026 | 1 | 4 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Process and apparatus for producing bleached cellulose24 Feb 2026US 12,559,885 B2Messer Austria GmbH
- Oxygen treatment of high kappa fibers29 Apr 2025US 12,286,751 B2GPCP IP Holdings LLC
- High efficiency fiber bleaching process12 Dec 2023US 11,840,805 B2GPCP IP Holdings LLC
- Method for producing bleached wood fibre material15 Aug 2023US 11,725,338 B2BASF SE
- Dissolving wood pulps and methods of making and using the same30 May 2023US 11,661,704 B2GP Cellulose GmbH
- Pulp mixture6 Aug 2026US 2026/0226680 A1SöDra SkogsäGarna Ekonomisk FöRening
- Method for bleaching cellulose pulp formed from recycled textile material9 Jul 2026US 2026/0193838 A1Valmet Corporation
- Pulp composition25 Jun 2026US 2026/0176820 A1Daikin Industries, Ltd.
- Producing nanofibers, microfibers, and lignin from lignocellulosic biomass22 Jan 2026US 2026/0022519 A1University of Washington
- Method for bleaching pulp from recycled textile material7 Dec 2023US 2023/0392320 A1Valmet Corporation
Most cited
By later US patents
- Chlorine free process for bleaching lignocellulosic pulp57US 4,372,812 AInternational Paper Company · 1983
- Pulp bleaching process comprising oxygen delignification and xylanase enzyme treatment45US 5,179,021 AGIL Inc. (now ICI Canada Inc.) · 1993
- Environmentally improved process for bleaching lignocellulosic materials with oxygen, ozone and chlorine dioxide40US 5,296,099 AUnion Camp Holding, Inc. · 1994
- Delignification of wood pulp by vanadium-substituted polyoxometalates37US 5,302,248 AThe United States of America as represented by the Secretary of Agriculture · 1994
- Oxidative delignification of wood or wood pulp by transition metal-substituted polyoxometalates37US 5,552,019 AEmory University · 1996