D21B

FIBROUS RAW MATERIALS OR THEIR MECHANICAL TREATMENT

In this subclass non-limiting references (in the sense of paragraph 39 of the Guide to the IPC) may still be displayed in the scheme.

D21B1/00

Fibrous raw materials or their mechanical treatment pretreatment of the finely-divided materials before digesting D21C1/00; methods of beating or refining pulp D21D1/00; purification of the pulp suspension by mechanical means D21D5/00

D21B1/02

Pretreatment of the raw materials by chemical or physical means removal of bark B27L

D21B1/021

by chemical means

D21B1/023

Cleaning wood chips or other raw materials

D21B1/025

Separating pith from fibrous vegetable materials

D21B1/026

Separating fibrous materials from waste

D21B1/028

by dry methods

D21B1/04

by dividing raw materials into small particles, e.g. fibres breaking-up or cutting wood or the like by dry methods B27L; mechanical separation of fibres from plant material D01B1/00; hackling or heckling machines D01B5/00

D21B1/06

by dry methods

D21B1/061

using cutting devices

D21B1/063

using grinding devices

D21B1/065

of the magazine type

D21B1/066

the raw material being pulp sheets

D21B1/068

by cutting actions

D21B1/08

the raw material being waste paper chemical part D21C5/02

the raw material being rags

D21B1/10

by cutting actions

D21B1/12

by wet methods, by the use of steam beaters D21D1/00

D21B1/14

Disintegrating in mills

D21B1/16

in the presence of chemical agents

D21B1/18

in magazine-type machines

D21B1/20

with chain feed

D21B1/22

with screw feed

D21B1/24

of the pocket type

D21B1/26

Driving or feeding arrangements

D21B1/28

Dressers for mill stones, combined with the mill

D21B1/30

Defibrating by other means

D21B1/303

using vibrating devices

D21B1/306

using microwaves

D21B1/32

of waste paper

D21B1/322

coated with synthetic materials

D21B1/325

de-inking devices

D21B1/327

using flotation devices

D21B1/34

Kneading or mixing

Pulpers

D21B1/342

Mixing apparatus

D21B1/345

Pulpers

D21B1/347

Rotor assemblies

D21B1/36

Explosive disintegration by sudden pressure reduction

D21B1/38

Conserving the finely-divided cellulosic material