C01G 21/20
Sulfates
C01G21/20 (Sulfates) appears on 18 US grants and 20 published applications in this corpus.
Search patents in C01G- Granted patents
- 18
- Published applications
- 20
- Assignees
- 12
- Inventors
- 32
- Latest grant
- 5 May 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1977 | 1 | 0 |
| 1978 | 0 | 0 |
| 1979 | 0 | 0 |
| 1980 | 0 | 0 |
| 1981 | 1 | 0 |
| 1982 | 1 | 0 |
| 1983 | 0 | 0 |
| 1984 | 0 | 0 |
| 1985 | 0 | 0 |
| 1986 | 0 | 0 |
| 1987 | 1 | 0 |
| 1988 | 0 | 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 | 1 | 0 |
| 1998 | 0 | 0 |
| 1999 | 0 | 0 |
| 2000 | 0 | 0 |
| 2001 | 0 | 0 |
| 2002 | 0 | 0 |
| 2003 | 0 | 0 |
| 2004 | 0 | 0 |
| 2005 | 0 | 1 |
| 2006 | 1 | 1 |
| 2007 | 1 | 0 |
| 2008 | 1 | 3 |
| 2009 | 2 | 0 |
| 2010 | 0 | 1 |
| 2011 | 0 | 1 |
| 2012 | 0 | 0 |
| 2013 | 0 | 0 |
| 2014 | 0 | 1 |
| 2015 | 0 | 0 |
| 2016 | 0 | 0 |
| 2017 | 0 | 0 |
| 2018 | 1 | 1 |
| 2019 | 0 | 0 |
| 2020 | 1 | 4 |
| 2021 | 3 | 2 |
| 2022 | 0 | 1 |
| 2023 | 0 | 1 |
| 2024 | 1 | 2 |
| 2025 | 1 | 1 |
| 2026 | 1 | 0 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Low alpha-ray emission stannous oxide and method of producing the same5 May 2026US 12,617,694 B2Mitsubishi Materials Corporation
- Nanocrystals22 Jul 2025US 12,365,599 B2Quantum Science Ltd
- Method of separating and recovering bromine from printed circuit board incineration ash by two-step process2 Jan 2024US 11,858,822 B2Beijing University of Technology
- Method of pretreatment and bromine recovery of PCB incineration ash14 Dec 2021US 11,198,615 B2Beijing University of Technology
- Systems and methods for producing potassium sulfate6 Apr 2021US 10,968,144 B2Marsulex Environmental Technologies Corporation
- Nanocrystals12 Jun 2025US 2025/0187939 A1Quantum Science Ltd
- Low alpha-ray emission stannous oxide and method of producing the same5 Sep 2024US 2024/0294391 A1Mitsubishi Materials Corporation
- Well-defined lead-acid battery active materials29 Feb 2024US 2024/0072256 A1
- A method of separating and recovering bromine from printed circuit board incineration ash by two-step process22 Jun 2023US 2023/0192488 A1Beijing University of Technology
- Nanocrystals2 Jun 2022US 2022/0169527 A1Quantum Science Ltd
Most cited
By later US patents
- Batteries and materials useful therein33US 5,660,600 ALucent Technologies Inc. · 1997
- Method of reducing lead and acid waste contamination in battery plant operation21US 4,024,055 AGlobe-Union Inc. · 1977
- Process for preparation of lead compounds10US 4,324,768 AMizusawa Kagaku Kozyo Kabushiki Kaisha · 1982
- Production of tetrabasic lead sulfate from solid state reactions for the preparation of active plates to be used in lead-acid batteries6US 7,011,805 B2GES Technologies IP GmbH · 2006
- Production of tetrabasic lead sulfate from solid state reactions for the preparation of active plates to be used in lead-acid batteries4US 7,309,478 B2GES Technologies IP GmbH · 2007