Skip to content
PCE
Search Classifications
Search for IPC and CPC classification codes or keywords
DIFF Subclass Not Allocatable
C23D

ENAMELLING OF, OR APPLYING A VITREOUS LAYER TO, METALS

Introduced: September 1968

Description

C23D encompasses the application of vitreous (glass-like) coatings to metallic surfaces through enamelling processes. This subclass covers the chemical composition of enamel materials, application techniques, firing methods, and surface preparation procedures specific to creating durable ceramic coatings on metals such as steel, copper, and aluminum. The classification includes ground coat formulations, cover coat systems, and specialized enamels for functional applications (e.g., cookware, sanitaryware, industrial equipment). C23D excludes other metallic coatings and non-vitreous surface treatments, which fall under different C23 divisions.

IPC and CPC are identically structured here. All 9 subcodes exist in both systems.

1 shared codes have differing titles between IPC and CPC.

Child Classifications

Navigate with arrow keys, Enter to open

  • C23D 11/00 Continuous processes; Apparatus therefor IPC+CPC Available in IPC and CPC
  • C23D 15/00 Joining enamelled articles to other enamelled articles by processes involving an enamelling step IPC+CPC Available in IPC and CPC
  • C23D 17/00 De-enamelling IPC+CPC Available in IPC and CPC
  • C23D 3/00 Chemical treatment of the metal surfaces prior to coating IPC+CPC Available in IPC and CPC
  • C23D 7/00 Treating the coatings, e.g. drying before burning IPC+CPC Available in IPC and CPC

Top Applicants

Top Applicants (IPC)

Class C23,2013–2023, worldwide · Source: EPO PATSTAT

  1. APPLIED MATERIALS US 8,096
  2. TOKYO ELECTRON JP 3,985
  3. CHINESE ACADEMY OF SCIENCES 2,842
  4. LAM RESEARCH CORPORATION US 2,654
  5. TOKYO ELECTRON 2,540
  6. NIPPON STEEL CORPORATION JP 2,465
  7. JFE STEEL JP 2,368
  8. ASM IP HOLDING NL 2,092
  9. APPLIED MATERIALS 1,877
  10. POSCO (POHANG IRON AND STEEL COMPANY) KR 1,782

Top Applicants (CPC)

Class C23,2013–2023, worldwide · Source: EPO PATSTAT

  1. APPLIED MATERIALS US 10,596
  2. TOKYO ELECTRON JP 5,229
  3. LAM RESEARCH CORPORATION US 3,622
  4. NIPPON STEEL CORPORATION JP 3,171
  5. JFE STEEL JP 3,128
  6. ASM IP HOLDING NL 2,722
  7. ARCELORMITTAL LU 2,481
  8. TOKYO ELECTRON 2,359
  9. APPLIED MATERIALS 2,284
  10. CHINESE ACADEMY OF SCIENCES 2,110