D21C 9/1005
Pretreatment of the pulp
Official title: {Pretreatment of the pulp, e.g. degassing the pulp}
D21C9/1005 (Pretreatment of the pulp) appears on 59 US grants and 27 published applications in this corpus.
Search patents in D21C- Granted patents
- 59
- Published applications
- 27
- Assignees
- 45
- Inventors
- 130
- Latest grant
- 21 Oct 2025
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1977 | 2 | 0 |
| 1978 | 1 | 0 |
| 1979 | 0 | 0 |
| 1980 | 0 | 0 |
| 1981 | 0 | 0 |
| 1982 | 0 | 0 |
| 1983 | 1 | 0 |
| 1984 | 1 | 0 |
| 1985 | 1 | 0 |
| 1986 | 1 | 0 |
| 1987 | 0 | 0 |
| 1988 | 3 | 0 |
| 1989 | 0 | 0 |
| 1990 | 1 | 0 |
| 1991 | 0 | 0 |
| 1992 | 2 | 0 |
| 1993 | 5 | 0 |
| 1994 | 4 | 0 |
| 1995 | 4 | 0 |
| 1996 | 5 | 0 |
| 1997 | 3 | 0 |
| 1998 | 0 | 0 |
| 1999 | 1 | 0 |
| 2000 | 3 | 0 |
| 2001 | 3 | 2 |
| 2002 | 2 | 0 |
| 2003 | 0 | 0 |
| 2004 | 3 | 2 |
| 2005 | 0 | 1 |
| 2006 | 0 | 2 |
| 2007 | 0 | 1 |
| 2008 | 1 | 0 |
| 2009 | 0 | 0 |
| 2010 | 0 | 1 |
| 2011 | 0 | 0 |
| 2012 | 0 | 0 |
| 2013 | 0 | 1 |
| 2014 | 2 | 1 |
| 2015 | 0 | 0 |
| 2016 | 0 | 0 |
| 2017 | 0 | 1 |
| 2018 | 0 | 3 |
| 2019 | 2 | 2 |
| 2020 | 0 | 2 |
| 2021 | 2 | 4 |
| 2022 | 2 | 2 |
| 2023 | 1 | 1 |
| 2024 | 1 | 0 |
| 2025 | 2 | 1 |
By publication year. Applications have been published since 2001.
Recent patents
- Preparation of cellulose fibers21 Oct 2025US 12,448,730 B2Jena Trading Aps
- High yield chemical pulping and bleaching process7 Oct 2025US 12,435,469 B2GPCP IP Holdings LLC
- Arrangement and method for degassing a pump24 Dec 2024US 12,173,451 B2Andritz Inc.
- Method for producing bleached wood fibre material15 Aug 2023US 11,725,338 B2BASF SE
- High consistency re-pulping method, apparatus and absorbent products incorporating recycled fiber1 Nov 2022US 11,486,089 B2GPCP IP Holdings LLC
- Arrangement and method for degassing a pump27 Mar 2025US 2025/0101681 A1Andritz Inc.
- High yield chemical pulping and bleaching process24 Aug 2023US 2023/0265609 A1GPCP IP Holdings LLC
- Preparation of cellulose fibers17 Mar 2022US 2022/0081833 A1Jena Trading Aps
- Arrangement and method for degassing a pump27 Jan 2022US 2022/0025578 A1Andritz Inc.
- Method for producing bleached wood fibre material19 Aug 2021US 2021/0254280 A1BASF SE
Most cited
By later US patents
- Process for producing a pulp suitable for papermaking from nonwood fibrous materials101US 6,302,997 B1HurterConsult Incorporated · 2001
- Process for acid bleaching of lignocellulose-containing pulp with a magnesium compound49US 6,398,908 B1Eka Nobel AB · 2002
- Dye removal in oxygen color stripping of secondary fibers35US 5,211,809 AAir Products and Chemicals, Inc. · 1993
- Acid treatment of pulp at high temperature prior to chlorine dioxide bleaching29US 6,306,253 B2Andritz-Ahlstrom Inc. · 2001
- Process for the oxygen bleaching of cellulose pulp25US 4,439,271 AMo och Domsjo Aktiebolag · 1984