D21F 1/0009
Regulating the freeness of the pulp
Official title: {Regulating the freeness of the pulp}
D21F1/0009 (Regulating the freeness of the pulp) appears on 16 US grants and 7 published applications in this corpus.
Search patents in D21F- Granted patents
- 16
- Published applications
- 7
- Assignees
- 12
- Inventors
- 36
- Latest grant
- 6 Oct 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1978 | 2 | 0 |
| 1979 | 0 | 0 |
| 1980 | 0 | 0 |
| 1981 | 1 | 0 |
| 1982 | 1 | 0 |
| 1983 | 1 | 0 |
| 1984 | 1 | 0 |
| 1985 | 1 | 0 |
| 1986 | 2 | 0 |
| 1987 | 1 | 0 |
| 1988 | 1 | 0 |
| 1989 | 0 | 0 |
| 1990 | 0 | 0 |
| 1991 | 0 | 0 |
| 1992 | 0 | 0 |
| 1993 | 0 | 0 |
| 1994 | 0 | 0 |
| 1995 | 0 | 0 |
| 1996 | 0 | 0 |
| 1997 | 0 | 0 |
| 1998 | 0 | 0 |
| 1999 | 0 | 0 |
| 2000 | 1 | 0 |
| 2001 | 0 | 0 |
| 2002 | 0 | 0 |
| 2003 | 0 | 0 |
| 2004 | 0 | 0 |
| 2005 | 0 | 0 |
| 2006 | 0 | 0 |
| 2007 | 0 | 0 |
| 2008 | 0 | 1 |
| 2009 | 0 | 0 |
| 2010 | 0 | 0 |
| 2011 | 1 | 1 |
| 2012 | 0 | 0 |
| 2013 | 0 | 1 |
| 2014 | 1 | 1 |
| 2015 | 0 | 0 |
| 2016 | 0 | 0 |
| 2017 | 0 | 0 |
| 2018 | 0 | 0 |
| 2019 | 0 | 0 |
| 2020 | 0 | 1 |
| 2021 | 0 | 0 |
| 2022 | 0 | 0 |
| 2023 | 0 | 1 |
| 2024 | 1 | 1 |
| 2025 | 0 | 0 |
| 2026 | 1 | 0 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Method for fractionation of highly refined cellulose6 Oct 2026US 12,753,551 B2Stora Enso OYJ
- System and method of producing micro fibrillated cellulose (MFC)11 Jun 2024US 12,006,628 B2Valmet Technologies Oy
- Methods for beating pulp, methods for treating process waters, and methods for producing pulp and paper22 Jul 2014US 8,784,608 B2Nippon Paper Industries Co., Ltd.
- Methods for beating pulp, methods for treating process waters, and methods for producing pulp and paper28 Jun 2011US 7,967,947 B2Nippon Paper Industries Co., Ltd.
- Method and apparatus for measuring the properties of a fiber or colloid suspension1 Feb 2000US 6,018,989 AMuetek Analytic GmbH
- Method for fractionation of highly refined cellulose2 May 2024US 2024/0141588 A1Stora Enso OYJ
- System and Method of Producing Micro Fibrillated Cellulose (MFC)22 Jun 2023US 2023/0193558 A1Valmet Technologies Oy
- A method for measuring disintegration of a fibrous product16 Apr 2020US 2020/0116620 A1Kemira Oyj
- Freeness of paper products2 Jan 2014US 2014/0000824 A9Catexel Limited
- Freeness of paper products23 May 2013US 2013/0126111 A1Catexel Limited
Most cited
By later US patents
- Method of measuring drainage rate21US 4,613,406 AWeyerhaeuser Company · 1986
- Method and apparatus for on-line monitoring of specific surface of mechanical pulps18US 4,276,119 ADomtar Inc. · 1981
- Method for controlling the digestion of pulp by IR spectroscopy16US 4,743,339 A1988
- Method and apparatus for on-line monitoring of specific surface of mechanical pulps15US 4,441,960 A1984
- Specific surface fractionator13US 4,386,519 A1983