IPC Subgroup
D21H 19/74 the substrate having an uneven surface, e.g. crêped or corrugated paper
Introduced: January 1990
Last revised: January 2006
Full Title
Coated paper; Coating material > Coated paper characterised by the paper substrate > the substrate having an uneven surface, e.g. crêped or corrugated paper
Classification Context
- Section:
- TEXTILES; PAPER
- Class:
- PAPER-MAKING; PRODUCTION OF CELLULOSE
- Subclass:
- PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES ,; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS OR SUBCLASS; PAPER NOT OTHERWISE PROVIDED FOR
Filing statistics
IPC D21H 19/74 belongs to the parent subclass D21H, which recorded 58,363 patent applications worldwide between 2013 and 2023. Annual filings grew from 4,545 in 2013 to 4,949 in 2023 (+9%), peaking at 6,006 applications in 2020. The most active applicants in class D21 are VOITH PATENT (1,809 applications), STORA ENSO (1,467 applications) and KEMIRA (1,086 applications).
Source: EPO PATSTAT, worldwide filings
Top Applicants
Top 10 applicants by patent filingsfor class D21, 2013–2023, worldwide · Source: EPO PATSTAT
- VOITH PATENT DE 1,809
- STORA ENSO FI 1,467
- KEMIRA FI 1,086
- KIMBERLY-CLARK CORPORATION US 935
- VALMET TECHNOLOGIES FI 924
- VALMET SE 904
- P&G (PROCTER & GAMBLE COMPANY) US 862
- OJI HOLDINGS CORPORATION 696
- OMYA INTERNATIONAL CH 584
- SOUTH CHINA UNIVERSITY OF TECHNOLOGY 571