D21C 9/144
With clo2/cl2 and other bleaching agents in a multistage process
Official title: {with ClO2/Cl2 and other bleaching agents in a multistage process}
D21C9/144 (With clo2/cl2 and other bleaching agents in a multistage process) appears on 58 US grants and 58 published applications in this corpus.
Search patents in D21C- Granted patents
- 58
- Published applications
- 58
- Assignees
- 37
- Inventors
- 101
- Latest grant
- 19 Aug 2025
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1980 | 1 | 0 |
| 1981 | 0 | 0 |
| 1982 | 0 | 0 |
| 1983 | 1 | 0 |
| 1984 | 0 | 0 |
| 1985 | 0 | 0 |
| 1986 | 0 | 0 |
| 1987 | 0 | 0 |
| 1988 | 0 | 0 |
| 1989 | 0 | 0 |
| 1990 | 1 | 0 |
| 1991 | 1 | 0 |
| 1992 | 0 | 0 |
| 1993 | 0 | 0 |
| 1994 | 0 | 0 |
| 1995 | 0 | 0 |
| 1996 | 1 | 0 |
| 1997 | 1 | 0 |
| 1998 | 2 | 0 |
| 1999 | 0 | 0 |
| 2000 | 2 | 0 |
| 2001 | 2 | 0 |
| 2002 | 1 | 1 |
| 2003 | 4 | 5 |
| 2004 | 3 | 3 |
| 2005 | 0 | 1 |
| 2006 | 0 | 2 |
| 2007 | 1 | 0 |
| 2008 | 1 | 2 |
| 2009 | 0 | 5 |
| 2010 | 0 | 1 |
| 2011 | 2 | 3 |
| 2012 | 3 | 3 |
| 2013 | 3 | 4 |
| 2014 | 3 | 3 |
| 2015 | 2 | 3 |
| 2016 | 2 | 3 |
| 2017 | 3 | 5 |
| 2018 | 7 | 3 |
| 2019 | 1 | 3 |
| 2020 | 4 | 2 |
| 2021 | 1 | 1 |
| 2022 | 1 | 1 |
| 2023 | 3 | 3 |
| 2024 | 0 | 0 |
| 2025 | 1 | 0 |
| 2026 | 0 | 1 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Treated Kraft pulp compositions and methods of making the same19 Aug 2025US 12,392,086 B2International Paper Company
- High efficiency fiber bleaching process12 Dec 2023US 11,840,805 B2GPCP IP Holdings LLC
- Modified cellulose from chemical kraft fiber and methods of making and using the same4 Jul 2023US RE49,570 E1GP Cellulose GmbH
- High efficiency fiber bleaching process28 Feb 2023US 11,591,751 B2GPCP IP Holdings LLC
- Treated Kraft pulp compositions and methods of making the same17 May 2022US 11,332,883 B2International Paper Company
- Method and system for recycling textile material30 Apr 2026US 2026/0117462 A1Valmet Corporation
- Treated kraft pulp compositions and methods of making the same16 Nov 2023US 2023/0366150 A1International Paper Company
- High Efficiency Fiber Bleaching Process1 Jun 2023US 2023/0167604 A1GPCP IP Holdings LLC
- Treated kraft pulp compositions and methods of making the same11 May 2023US 2023/0142284 A1International Paper Company
- Method for manufacturing bleached pulp, feedstock, and packaging system25 Aug 2022US 2022/0267957 A1WestRock MWV, LLC
Most cited
By later US patents
- Process of bleaching softwood pulps in a D1 or D2 stage in a presence of a weak base29US 7,976,676 B2International Paper Company · 2011
- Method of bleaching kraft pulp in a DZED sequence19US 4,959,124 AInternational Paper Company · 1990
- Elemental-chlorine-free bleaching process having an initial Eo or Eop stage11US 6,569,284 B1International Paper Company · 2003
- Modified cellulose from chemical kraft fiber and methods of making and using the same10US 8,778,136 B2GP Cellulose GmbH · 2014
- Method for complex treatment of pulp in conjunction with a chlorine dioxide stage9US 6,258,208 B1Mo och Domsjo Aktiebolag · 2001