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PCE
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CPC Subgroup
D21H 23/04

Addition to the pulp; After-treatment of added substances in the pulp

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 pulp; After-treatment of added substances in the pulp

2 direct subcodes

Child Classifications

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Top Applicants

Top 10 applicants by patent filingsfor class D21, 2013–2023, worldwide · Source: EPO PATSTAT

  1. VOITH PATENT DE 1,857
  2. STORA ENSO FI 1,552
  3. KEMIRA FI 1,173
  4. KIMBERLY-CLARK CORPORATION US 1,107
  5. VALMET TECHNOLOGIES FI 965
  6. VALMET SE 943
  7. P&G (PROCTER & GAMBLE COMPANY) US 941
  8. OMYA INTERNATIONAL CH 821
  9. UPM-KYMMENE CORPORATION FI 512
  10. SEIKO EPSON CORPORATION JP 501