CPC Subgroup
D21H 23/56 Rolls (D21H23/38 takes precedence)
Full Title
Processes or apparatus for adding material to the pulp or to the paper (applying liquids or other fluent material to surfaces, in general B05; processes for making continuous lengths of paper D21F11/00) > characterised by the manner in which substances are added > Addition to the formed paper > by contacting paper with a device carrying the material (D21H23/32, D21H23/46, D21H23/66 take precedence) > Rolls (D21H23/38 takes precedence)
1 direct subcode
Child Classifications
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- D21H 23/58 Details thereof, e.g. surface characteristics, peripheral speed
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