WebCPC CPC COOPERATIVE PATENT CLASSIFICATION

D21B　FIBROUS RAW MATERIALS OR THEIR MECHANICAL TREATMENT

D21B 1/00 Fibrous raw materials or their mechanical treatment

D21B 1/02 ・Pretreatment of the raw materials by chemical or physical means (removal of bark B27L)

D21B 1/021 ・・{by chemical means}

D21B 1/023 ・・{Cleaning wood chips or other raw materials}

D21B 1/025 ・・{Separating pith from fibrous vegetable materials}

D21B 1/026 ・・{Separating fibrous materials from waste}

D21B 1/028 ・・・{by dry methods}

D21B 1/04 ・by dividing raw materials into small particles, e.g. fibres (breaking-up or cutting wood or the like by dry methods B27L; disintegrating peat C10F 7/02; obtaining fibres mechanically for spinning from rags, peat, or the like D01B)

D21B 1/06 ・・by dry methods

D21B 1/061 ・・・{using cutting devices}

D21B 1/063 ・・・{using grinding devices}

D21B 1/065 ・・・・{of the magazine type}

D21B 1/066 ・・・{the raw material being pulp sheets}

D21B 1/068 ・・・・{by cutting actions}

D21B 1/08 ・・・the raw material being waste paper (chemical part D21C 5/02); the raw material being rags

D21B 1/10 ・・・・by cutting actions

D21B 1/12 ・・by wet methods, by the use of steam (beaters D21D 1/00)

D21B 1/14 ・・・Disintegrating in mills (in general B02C)

D21B 1/16 ・・・・in the presence of chemical agents

D21B 1/18 ・・・・in magazine-type machines

D21B 1/20 ・・・・・with chain feed

D21B 1/22 ・・・・・with screw feed

D21B 1/24 ・・・・・of the pocket type

D21B 1/26 ・・・・Driving or feeding arrangements

D21B 1/28 ・・・・Dressers for mill stones, combined with the mill

D21B 1/30 ・・・Defibrating by other means

D21B 1/303 ・・・・{using vibrating devices}

D21B 1/306 ・・・・{using microwaves}

D21B 1/32 ・・・・of waste paper

D21B 1/322 ・・・・・{coated with synthetic materials}

D21B 1/325 ・・・・・{de-inking devices}

D21B 1/327 ・・・・・・{using flotation devices}

D21B 1/34 ・・・・Kneading or mixing; Pulpers

D21B 1/342 ・・・・・{Mixing apparatus}

D21B 1/345 ・・・・・{Pulpers}

D21B 1/347 ・・・・・・{Rotor assemblies}

D21B 1/36 ・・・・Explosive disintegration by sudden pressure reduction

D21B 1/38 ・Conserving the finely-divided cellulosic material