CPC Subgroup
D21H 27/08 Filter paper (self-supporting filtering material B01D39/14; making on paper-making machines D21F11/14)
Full Title
Special paper not otherwise provided for, e.g. made by multi-step processes > Filter paper (self-supporting filtering material B01D39/14; making on paper-making machines D21F11/14)
Top Applicants
Top 10 applicants by patent filingsfor class D21, 2013–2023, worldwide · Source: EPO PATSTAT
- VOITH PATENT DE 1,857
- STORA ENSO FI 1,552
- KEMIRA FI 1,173
- KIMBERLY-CLARK CORPORATION US 1,107
- VALMET TECHNOLOGIES FI 965
- VALMET SE 943
- P&G (PROCTER & GAMBLE COMPANY) US 941
- OMYA INTERNATIONAL CH 821
- UPM-KYMMENE CORPORATION FI 512
- SEIKO EPSON CORPORATION JP 501