IPC 2013 : D21H 15/12 : partly organic, partly inorganic.

IPC2013 > D > D21 > D21H > D21H 15/00 > D21H 15/12[3] > partly organic, partly inorganic.
D SECTION D — TEXTILES; PAPER.
D21 PAPER-MAKING; PRODUCTION OF CELLULOSE.
D21H PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C, D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR.
D21H 15/00 Pulp or paper, comprising fibres or web-forming material characterised by features other than their chemical constitution.
D21H 15/12 · · · partly organic, partly inorganic.