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DIFF Subgroup
D21H 21/30

Luminescent or fluorescent substances, e.g. for optical bleaching (D21H21/40 takes precedence)

Introduced: January 1990

Title

Titles differ between systems:

IPC: Luminescent or fluorescent substances, e.g. for optical bleaching

CPC: Luminescent or fluorescent substances, e.g. for optical bleaching (D21H21/40 takes precedence)

Full Title

Full titles differ between systems:

IPC:

Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper impregnating or coating material, characterised by its function, form or properties > characterised by function or properties in or on the paper > Luminescent or fluorescent substances, e.g. for optical bleaching

CPC:

Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties > characterised by function or properties in or on the paper (D21H19/66, D21H27/02 take precedence) > Luminescent or fluorescent substances, e.g. for optical bleaching (D21H21/40 takes precedence)

No child classifications to compare. This is a leaf node in both IPC and CPC.

Top Applicants

Top Applicants (IPC)

Class D21,2013–2023, worldwide · Source: EPO PATSTAT

  1. VOITH PATENT DE 1,809
  2. STORA ENSO FI 1,467
  3. KEMIRA FI 1,086
  4. KIMBERLY-CLARK CORPORATION US 935
  5. VALMET TECHNOLOGIES FI 924
  6. VALMET SE 904
  7. P&G (PROCTER & GAMBLE COMPANY) US 862
  8. OJI HOLDINGS CORPORATION 696
  9. OMYA INTERNATIONAL CH 584
  10. SOUTH CHINA UNIVERSITY OF TECHNOLOGY 571

Top Applicants (CPC)

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