CPC Definition - Subclass D21J
This place covers:
Manufacture of fibreboard and articles from cellulosic fibrous suspensions by wet methods, and fibreboard product obtained thereby.
This place does not cover:
Attention is drawn to the following places, which may be of interest for search:
Cellulosic materials in the methods for working plastic materials | B29K 2001/00, B29B, B29C, B29D |
Making other paper articles than boxes, cartons, envelopes, bags and tubes | |
Making layered products not composed wholly of paper or cardboard | |
Building materials |
Subgroups and head groups.
If a document concerns embodiments which are covered by several subgroups dependent on a higher hierarchy group, the following rules apply:
the specific technical information relevant for some of the subgroups is classified in all said subgroups;
if relevant, the structural association (e.g. the combination) of the elements covered by the subgroups is classified in the head group;
analogously, if generic technical information common to all of the subgroups is disclosed and only schematic embodiments of the specific subgroup embodiments are represented, the documents is classified in the head group only.
This place covers:
Processes and devices for the production of wet-formed board from raw materials comprising fibrous materials and optionally all kind of other filler material.
This place covers:
Fibreboard specially adapted for a certain purpose.
This place covers:
e.g. acoustic or thermal insulating board.
This place covers:
Fibreboard manufacturing processes without the use of vacuum, i.e. only pressing the moulds together.
This place covers:
Fibreboard manufacturing processes comprising sheet forming and subsequent moulding/pressing.
This place covers:
Fibreboard manufacturing processes comprising simultaneous forming and moulding.