D21C 9/1089
With dithionites
Official title: {with dithionites}
D21C9/1089 (With dithionites) appears on 23 US grants and 12 published applications in this corpus.
Search patents in D21C- Granted patents
- 23
- Published applications
- 12
- Assignees
- 14
- Inventors
- 57
- Latest grant
- 15 Aug 2023
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 3 | 0 |
| 1977 | 0 | 0 |
| 1978 | 1 | 0 |
| 1979 | 0 | 0 |
| 1980 | 0 | 0 |
| 1981 | 0 | 0 |
| 1982 | 1 | 0 |
| 1983 | 0 | 0 |
| 1984 | 0 | 0 |
| 1985 | 0 | 0 |
| 1986 | 1 | 0 |
| 1987 | 0 | 0 |
| 1988 | 1 | 0 |
| 1989 | 1 | 0 |
| 1990 | 1 | 0 |
| 1991 | 0 | 0 |
| 1992 | 0 | 0 |
| 1993 | 0 | 0 |
| 1994 | 0 | 0 |
| 1995 | 1 | 0 |
| 1996 | 0 | 0 |
| 1997 | 1 | 0 |
| 1998 | 0 | 0 |
| 1999 | 0 | 0 |
| 2000 | 1 | 0 |
| 2001 | 1 | 0 |
| 2002 | 0 | 1 |
| 2003 | 1 | 0 |
| 2004 | 0 | 4 |
| 2005 | 0 | 0 |
| 2006 | 1 | 0 |
| 2007 | 2 | 0 |
| 2008 | 0 | 0 |
| 2009 | 0 | 0 |
| 2010 | 0 | 2 |
| 2011 | 2 | 2 |
| 2012 | 0 | 0 |
| 2013 | 0 | 0 |
| 2014 | 1 | 0 |
| 2015 | 0 | 0 |
| 2016 | 0 | 0 |
| 2017 | 0 | 0 |
| 2018 | 0 | 2 |
| 2019 | 0 | 0 |
| 2020 | 1 | 0 |
| 2021 | 1 | 1 |
| 2022 | 0 | 0 |
| 2023 | 1 | 0 |
By publication year. Applications have been published since 2001.
Recent patents
- Method for producing bleached wood fibre material15 Aug 2023US 11,725,338 B2BASF SE
- Method for producing bleached wood fibre material25 May 2021US 11,015,290 B2BASF SE
- Stabilization of sodium dithionite by means of various additives1 Dec 2020US 10,850,982 B2BASF SE
- Process for the production of bleached wood particles and pale to white wood-base materials22 Jul 2014US 8,784,607 B2BASF SE
- Environmentally benign TCF bleaching sequences for AS/AQ wheat straw pulp20 Dec 2011US 8,080,129 B2
- Method for producing bleached wood fibre material19 Aug 2021US 2021/0254280 A1BASF SE
- Method for producing bleached wood fibre material2 Aug 2018US 2018/0216292 A1BASF SE
- Stabilization of sodium dithionite by means of various additives17 May 2018US 2018/0134557 A1BASF SE
- Bleaching method25 Aug 2011US 2011/0203485 A1Kemira Oyj
- Environmentally benign tcf bleaching sequences for as/aq wheat straw pulp19 May 2011US 2011/0114273 A1
Most cited
By later US patents
- Stabilized sodium dithionite solutions15US 3,985,674 AVirginia Chemicals Inc. · 1976
- Process for de-inking recycled paper pulp with a reducing agent13US 5,429,716 AMorton International, Inc. · 1995
- Wood pulp bleaching composition containing sodium hydrosulfite and hexamethylenetetramine8US 3,960,649 AVentron Corporation · 1976
- Process for bleaching5US 4,919,755 AEka Nobel AB · 1990
- Bleaching wood pulp with sodium hydrosulfite in the presence of hexamethylenetetramine4US 3,962,030 AVentron Corporation · 1976