D21D 1/20
Methods of refining
D21D1/20 (Methods of refining) appears on 688 US grants and 483 published applications in this corpus.
Search patents in D21D- Granted patents
- 688
- Published applications
- 483
- Assignees
- 257
- Inventors
- 970
- Latest grant
- 22 Sep 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 8 | 0 |
| 1977 | 10 | 0 |
| 1978 | 9 | 0 |
| 1979 | 6 | 0 |
| 1980 | 10 | 0 |
| 1981 | 16 | 0 |
| 1982 | 5 | 0 |
| 1983 | 8 | 0 |
| 1984 | 8 | 0 |
| 1985 | 9 | 0 |
| 1986 | 12 | 0 |
| 1987 | 15 | 0 |
| 1988 | 8 | 0 |
| 1989 | 10 | 0 |
| 1990 | 15 | 0 |
| 1991 | 17 | 0 |
| 1992 | 15 | 0 |
| 1993 | 19 | 0 |
| 1994 | 13 | 0 |
| 1995 | 18 | 0 |
| 1996 | 14 | 0 |
| 1997 | 17 | 0 |
| 1998 | 24 | 0 |
| 1999 | 16 | 0 |
| 2000 | 7 | 0 |
| 2001 | 17 | 8 |
| 2002 | 10 | 13 |
| 2003 | 16 | 12 |
| 2004 | 6 | 13 |
| 2005 | 13 | 14 |
| 2006 | 7 | 18 |
| 2007 | 14 | 15 |
| 2008 | 11 | 17 |
| 2009 | 9 | 15 |
| 2010 | 15 | 13 |
| 2011 | 14 | 13 |
| 2012 | 13 | 18 |
| 2013 | 11 | 18 |
| 2014 | 12 | 24 |
| 2015 | 19 | 16 |
| 2016 | 7 | 15 |
| 2017 | 10 | 21 |
| 2018 | 15 | 20 |
| 2019 | 16 | 28 |
| 2020 | 19 | 31 |
| 2021 | 20 | 34 |
| 2022 | 21 | 30 |
| 2023 | 26 | 23 |
| 2024 | 26 | 27 |
| 2025 | 23 | 16 |
| 2026 | 9 | 11 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Refiner filling piece having multiple coatings on bars22 Sep 2026US 12,742,288 B2Aikawa Fiber Technologies Oy
- Blade for a refiner for refining lignocellulosic material, and refiner comprising at least one blade4 Aug 2026US 12,698,591 B2Valmet Corporation
- Pulp mixture21 Apr 2026US 12,606,957 B2Alpla Werke Alwin Lehner GmbH & Co. KG
- Beating gap sensor device for a refiner apparatus and calibration method24 Mar 2026US 12,584,723 B2Daprox AB
- Deflaking element for pulper10 Mar 2026US 12,571,161 B2Kadant Black Clawson LLC
- Blade for a refiner for refining lignocellulosic material, and refiner comprising at least one blade1 Oct 2026US 2026/0297848 A1Valmet Corporation
- Method and plant for dense pulp refining for papermaking17 Sep 2026US 2026/0275633 A1
- Method, system and program for producing a refiner segment out of a worn refiner segment, and a rebuilt refiner segment20 Aug 2026US 2026/0241456 A1Valmet Corporation
- Production of ctmp from a hardwood/softwood mixture23 Jul 2026US 2026/0210039 A1Billerud Aktiebolag (publ)
- Process of using non-wood fibers to create paper pulp16 Jul 2026US 2026/0201639 A1
Most cited
By later US patents
- Super microfibrillated cellulose, process for producing the same, and coated paper and tinted paper using the same136US 6,183,596 B2Tokushu Paper Mfg. Co., Ltd. · 2001
- System and method for producing bonded fiber/cellulose products111US 8,795,470 B22014
- Super microfibrillated cellulose, process for producing the same, and coated paper and tinted paper using the same110US 6,214,163 B1Tokushu Paper Mfg. Co., Ltd. · 2001
- Method and apparatus for manufacturing microfibrillated cellulose fiber109US 7,381,294 B2Japan Absorbent Technology Institute · 2008
- Process for making microdenominated cellulose91US 5,385,640 AMicrocell Corporation · 1995