C21D 9/18
Heat treatment: for knives, scythes, scissors, or like hand cutting tools
Official title: for knives, scythes, scissors, or like hand cutting tools
C21D9/18 (Heat treatment: for knives, scythes, scissors, or like hand cutting tools) appears on 47 US grants and 59 published applications in this corpus.
Search patents in C21D- Granted patents
- 47
- Published applications
- 59
- Assignees
- 55
- Inventors
- 144
- Latest grant
- 7 Jul 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 1 | 0 |
| 1977 | 0 | 0 |
| 1978 | 0 | 0 |
| 1979 | 0 | 0 |
| 1980 | 0 | 0 |
| 1981 | 2 | 0 |
| 1982 | 3 | 0 |
| 1983 | 1 | 0 |
| 1984 | 1 | 0 |
| 1985 | 0 | 0 |
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| 1988 | 1 | 0 |
| 1989 | 0 | 0 |
| 1990 | 0 | 0 |
| 1991 | 0 | 0 |
| 1992 | 0 | 0 |
| 1993 | 0 | 0 |
| 1994 | 2 | 0 |
| 1995 | 2 | 0 |
| 1996 | 0 | 0 |
| 1997 | 0 | 0 |
| 1998 | 0 | 0 |
| 1999 | 4 | 0 |
| 2000 | 1 | 0 |
| 2001 | 1 | 0 |
| 2002 | 0 | 1 |
| 2003 | 0 | 0 |
| 2004 | 0 | 1 |
| 2005 | 1 | 1 |
| 2006 | 0 | 2 |
| 2007 | 0 | 4 |
| 2008 | 0 | 5 |
| 2009 | 0 | 1 |
| 2010 | 4 | 0 |
| 2011 | 0 | 2 |
| 2012 | 3 | 3 |
| 2013 | 3 | 3 |
| 2014 | 1 | 4 |
| 2015 | 1 | 1 |
| 2016 | 2 | 8 |
| 2017 | 2 | 0 |
| 2018 | 1 | 1 |
| 2019 | 1 | 3 |
| 2020 | 1 | 4 |
| 2021 | 1 | 2 |
| 2022 | 1 | 2 |
| 2023 | 1 | 4 |
| 2024 | 1 | 4 |
| 2025 | 3 | 1 |
| 2026 | 1 | 2 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Steel for knives, steel for martensitic knives, knife, and production method for steel for martensitic knives7 Jul 2026US 12,674,218 B2Proterial, Ltd.
- Blank for a Damascus patterned article18 Nov 2025US 12,473,616 B2Damasteel AB
- Razor blade and composition for a razor blade4 Mar 2025US 12,240,136 B2Edgewell Personal Care Brands, LLC
- Method for manufacturing steel strip for blade, and steel strip for blade14 Jan 2025US 12,195,821 B2Proterial, Ltd.
- Method for manufacturing kitchen knife by using multilayer material20 Aug 2024US 12,064,837 B2Kongju National University Industry-University Cooperation Foundation
- Steel for knives20 Aug 2026US 2026/0242886 A1Proterial, Ltd.
- Method of manufacturing a stainless steel sheet15 Jan 2026US 2026/0015684 A1Jfe Steel Corporation
- Non-magnetic fine stainless steel processed product and method for manufacturing the same19 Jun 2025US 2025/0195270 A1Terakata Manufacturing Co., Ltd,
- Long Cutting Knife19 Sep 2024US 2024/0308102 A1Kanefusa Kabushiki Kaisha
- Process for obtaining a fine-grained martensitic structure component15 Aug 2024US 2024/0271239 A1Danmarks Tekniske Universitet
Most cited
By later US patents
- Methods for making cutting tools49US 4,755,237 A1988
- Rotary cutting blade having a laser hardened cutting edge and a method for making the same with a laser38US 5,906,053 AFisher Barton, Inc. · 1999
- Razor blade steel having high corrosion resistance and differential residual austenite content23US 5,275,672 AHitachi Metals, Ltd. · 1994
- Cutting members for shaving razors20US 8,499,462 B2The Gillette Company · 2013
- Induction hardened blade17US 8,316,550 B2Stanley Black & Decker, Inc. · 2012