Top IPC subclasses
1
|
C03C
|
4
|
chemical composition of glasses, glazes, or vitreous enamelssurface treatment of glasssurface treatm
|
2
|
C02F
|
3
|
Treatment of water, waste water, sewage, or sludge
|
3
|
B01D
|
2
|
Separation
|
4
|
B01J
|
2
|
Chemical or physical processes, e.g. catalysis, colloid chemistry; their relevant apparatus
|
5
|
C09C
|
2
|
treatment of inorganic materials, other than fibrous fillers, to enhance their pigmenting or filling
|