|  | D |
SECTION D — TEXTILES; PAPER

PAPER

|  | D21 |
PAPER-MAKING; PRODUCTION OF CELLULOSE

|  | D21H |
PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES Fulltext... Hierarchy... Expanded...D21C, Fulltext... Hierarchy... Expanded...D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS Fulltext... Hierarchy... Expanded...B31 OR SUBCLASS Fulltext... Hierarchy... Expanded...D21G; PAPER NOT OTHERWISE PROVIDED FOR [5]

|  | D21H |
Note(s) This subclass covers also pulp compositions for the preparation of fibreboard or other fibrous articles by wet processes. [5] In this subclass, the following terms are used with the meaning indicated: "pulp" means a dispersion comprising paper-making fibres and optional additives, which is to be processed, and covers the term "stock"; it also means dry paper-making fibres which are to be made into paper by either wet or dry processes; [5] "paper" means paper, cardboard or wet-laid non-woven fabrics. If a pulp composition or a paper, or a constituent thereof, is characterised by more than one feature provided for in this subclass, for example, by both the fibrous material and a coating or by both a colorant and a water-repelling agent, classification is made in all places providing for these features. [8] Processes using enzymes or micro-organisms in order to: liberate, separate or purify a pre-existing compound or composition, or to treat textiles or clean solid surfaces of materials are further classified in subclass Fulltext... Hierarchy... Expanded...C12S. [5]

|  | D21H |
Subclass index
PULP OR PAPER |
comprising cellulose, lignocellulose or non-cellulose fibres or web-forming material | 11/00, 13/00
comprising fibres or web-forming material not characterised by their chemical constitution | 15/00
Processes or apparatus for adding material | 23/00
NON-FIBROUS MATERIAL ADDED TO THE PULP, PAPER-IMPREGNATING MATERIAL | 17/00, 21/00
COATED PAPER; COATING MATERIAL | 19/00
OTHER AFTER-TREATMENTS OF PAPER | 25/00
SPECIAL PAPER | 27/00

|  | D21H 11/00 - D21H 15/00 |
Note(s) In groups Fulltext... Hierarchy... Expanded...Fulltext... Hierarchy... Expanded...D21H 11/00-D21H 15/00, in the absence of an indication to the contrary, classification is made in the last appropriate place. [5]

P:30 |  | D21H 11/00 |
Pulp or paper, comprising cellulose or lignocellulose fibres of natural origin only [5]

|  | D21H 11/02 |
· | Chemical or chemomechanical pulp [5]

|  | D21H 11/04 |
· · | Kraft or sulfate pulp [5]

|  | D21H 11/06 |
· · | Sulfite or bisulfite pulp [5]

|  | D21H 11/08 |
· | Mechanical or thermomechanical pulp [5]

|  | D21H 11/10 |
· | Mixtures of chemical and mechanical pulp [5]

|  | D21H 11/12 |
· | Pulp from non-woody plants or crops, e.g. cotton, flax, straw, bagasse [5]

|  | D21H 11/14 |
· | Secondary fibres (working-up waste paper Fulltext... Hierarchy... Expanded...D21C 5/02) [5]

|  | D21H 11/16 |
· | modified by a particular after-treatment [5]

|  | D21H 11/18 |
· · | Highly hydrated, swollen or fibrillatable fibres [5]

|  | D21H 11/20 |
· · | Chemically or biochemically modified fibres [5]

|  | D21H 11/22 |
· · · | cationised [5]

P:20 |  | D21H 13/00 |
Pulp or paper, comprising synthetic cellulose or non-cellulose fibres or web-forming material (chemical features in the manufacture of artificial fibres Fulltext... Hierarchy... Expanded...D01F) [5]

|  | D21H 13/02 |
· | Synthetic cellulose fibres [5]

|  | D21H 13/04 |
· · | Cellulose ethers [5]

|  | D21H 13/06 |
· · | Cellulose esters [5]

|  | D21H 13/08 |
· · | from regenerated cellulose [5]

|  | D21H 13/10 |
· | Organic non-cellulose fibres [5]

|  | D21H 13/12 |
· · | from macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds [5]

|  | D21H 13/14 |
· · · | Polyalkenes, e.g. polystyrene [5]

|  | D21H 13/16 |
· · · | Polyalkenylalcohols; Polyalkenylethers; Polyalkenylesters [5]

|  | D21H 13/18 |
· · · | Polymers of unsaturated acids or derivatives thereof, e.g. polyacrylonitriles [5]

|  | D21H 13/20 |
· · | from macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds [5]

|  | D21H 13/22 |
· · · | Condensation polymers of aldehydes or ketones [5]

|  | D21H 13/24 |
· · · | Polyesters [5]

|  | D21H 13/26 |
· · · | Polyamides; Polyimides [5]

|  | D21H 13/28 |
· · | from natural polymers [5]

|  | D21H 13/30 |
· · · | Non-cellulose polysaccharides [5]

|  | D21H 13/32 |
· · · · | Alginate fibres [5]

|  | D21H 13/34 |
· · · | Protein fibres [5]

|  | D21H 13/36 |
· | Inorganic fibres or flakes [5]

|  | D21H 13/38 |
· · | siliceous [5]

|  | D21H 13/40 |
· · · | vitreous, e.g. mineral wool, glass fibres [5]

|  | D21H 13/42 |
· · · | Asbestos [5]

|  | D21H 13/44 |
· · · | Flakes, e.g. mica, vermiculite [5]

|  | D21H 13/46 |
· · | Non-siliceous fibres, e.g. from metal oxides [5]

|  | D21H 13/48 |
· · · | Metal or metallised fibres [5]

|  | D21H 13/50 |
· · · | Carbon fibres [5]

P:10 |  | D21H 15/00 |
Pulp or paper, comprising fibres or web-forming material characterised by features other than their chemical constitution [5]

|  | D21H 15/02 |
· | characterised by configuration [5]

|  | D21H 15/04 |
· · | crimped, kinked, curled or twisted fibres [5]

|  | D21H 15/06 |
· · | Long fibres, i.e. fibres exceeding the upper length limit of conventional paper-making fibres; Filaments [5]

|  | D21H 15/08 |
· · | Flakes (Fulltext... Hierarchy... Expanded...D21H 13/44 takes precedence) [5]

|  | D21H 15/10 |
· · | Composite fibres [5]

|  | D21H 15/12 |
· · · | partly organic, partly inorganic [5]

P:60 |  | D21H 17/00 |
Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution [5]

|  | D21H 17/01 - D21H 17/63 |
Note(s) In groups Fulltext... Hierarchy... Expanded...Fulltext... Hierarchy... Expanded...D21H 17/01-D21H 17/63, in the absence of an indication to the contrary, a material is classified in the last appropriate place. [8] A mixture of two or more materials is classified in the last appropriate place in groups Fulltext... Hierarchy... Expanded...Fulltext... Hierarchy... Expanded...D21H 17/01-D21H 17/63 that provides for at least one of these materials. [8] Any part of a mixture which is not identified by the classification according to note (2), and which itself is determined to be novel and non-obvious, must also be classified in the last appropriate place in groups Fulltext... Hierarchy... Expanded...Fulltext... Hierarchy... Expanded...D21H 17/01-D21H 17/63. The part can be either a single material or a mixture in itself. [8] A part of a mixture which is not identified by the classification according to note (2) or (3), and which is considered to represent information of interest for search, may also be classified in the last appropriate place in groups Fulltext... Hierarchy... Expanded...Fulltext... Hierarchy... Expanded...D21H 17/01-D21H 17/63. This can for example be the case when it is considered of interest to enable searching of mixtures using a combination of classification symbols. Such non-obligatory classification should be given as "additional information". [8]

|  | D21H 17/01 |
· | Waste products, e.g. sludge [5]

|  | D21H 17/02 |
· | Material of vegetable origin (proteins Fulltext... Hierarchy... Expanded...D21H 17/22; lignins Fulltext... Hierarchy... Expanded...D21H 17/23; polysaccharides Fulltext... Hierarchy... Expanded...D21H 17/24; rosin Fulltext... Hierarchy... Expanded...D21H 17/62) [5]

|  | D21H 17/03 |
· | Non-macromolecular organic compounds [5]

|  | D21H 17/04 |
· · | Hydrocarbons [5]

|  | D21H 17/05 |
· · | containing elements other than carbon and hydrogen only [5]

|  | D21H 17/06 |
· · · | Alcohols; Phenols; Ethers; Aldehydes; Ketones; Acetals; Ketals [5]

|  | D21H 17/07 |
· · · | Nitrogen-containing compounds [5]

|  | D21H 17/08 |
· · · · | Isocyanates [5]

|  | D21H 17/09 |
· · · | Sulfur-containing compounds [5]

|  | D21H 17/10 |
· · · | Phosphorus-containing compounds [5]

|  | D21H 17/11 |
· · · | Halides [5]

|  | D21H 17/12 |
· · · | Organo-metallic compounds [5]

|  | D21H 17/13 |
· · · | Silicon-containing compounds [5]

|  | D21H 17/14 |
· · · | Carboxylic acids; Derivatives thereof [5]

|  | D21H 17/15 |
· · · · | Polycarboxylic acids, e.g. maleic acid [5]

|  | D21H 17/16 |
· · · · · | Addition products thereof with hydrocarbons [5]

|  | D21H 17/17 |
· · · | Ketenes, e.g. ketene dimers [5]

|  | D21H 17/18 |
· · · | forming new compounds in situ, e.g. within the pulp or paper, by chemical reaction with itself, or other added substances [5]

|  | D21H 17/19 |
· · · · | by reactions only involving carbon-to-carbon unsaturated bonds [5]

|  | D21H 17/20 |
· | Macromolecular organic compounds [5]

|  | D21H 17/21 |
· · | of natural origin; Derivatives thereof [5]

|  | D21H 17/22 |
· · · | Proteins [5]

|  | D21H 17/23 |
· · · | Lignins [5]

|  | D21H 17/24 |
· · · | Polysaccharides [5]

|  | D21H 17/25 |
· · · · | Cellulose [5]

|  | D21H 17/26 |
· · · · · | Ethers thereof [5]

|  | D21H 17/27 |
· · · · · | Esters thereof [5]

|  | D21H 17/28 |
· · · · | Starch [5]

|  | D21H 17/29 |
· · · · · | cationic [5]

|  | D21H 17/30 |
· · · · | Alginic acid or alginates [5]

|  | D21H 17/31 |
· · · · | Gums [5]

|  | D21H 17/32 |
· · · · · | Guar gum [5]

|  | D21H 17/33 |
· · | Synthetic macromolecular compounds [5]

|  | D21H 17/34 |
· · · | obtained by reactions only involving carbon-to-carbon unsaturated bonds [5]

|  | D21H 17/35 |
· · · · | Polyalkenes, e.g. polystyrene [5]

|  | D21H 17/36 |
· · · · | Polyalkenylalcohols; Polyalkenylethers; Polyalkenylesters [5]

|  | D21H 17/37 |
· · · · | Polymers of unsaturated acids or derivatives thereof, e.g. polyacrylates [5]

|  | D21H 17/38 |
· · · · | containing crosslinkable groups [5]

|  | D21H 17/39 |
· · · · · | forming ether crosslinkages, e.g. alkylol groups [5]

|  | D21H 17/40 |
· · · · · | unsaturated [5]

|  | D21H 17/41 |
· · · · | containing ionic groups [5]

|  | D21H 17/42 |
· · · · · | anionic [5]

|  | D21H 17/43 |
· · · · · · | Carboxyl groups or derivatives thereof [5]

|  | D21H 17/44 |
· · · · · | cationic [5]

|  | D21H 17/45 |
· · · · · · | Nitrogen-containing groups [5]

|  | D21H 17/46 |
· · · | obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds [5]

|  | D21H 17/47 |
· · · · | Condensation polymers of aldehydes or ketones [5]

|  | D21H 17/48 |
· · · · · | with phenols [5]

|  | D21H 17/49 |
· · · · · | with compounds containing hydrogen bound to nitrogen [5]

|  | D21H 17/50 |
· · · · · · | Acyclic compounds [5]

|  | D21H 17/51 |
· · · · · · | Triazines, e.g. melamine [5]

|  | D21H 17/52 |
· · · · | Epoxy resins [5]

|  | D21H 17/53 |
· · · · | Polyethers; Polyesters [5]

|  | D21H 17/54 |
· · · · | obtained by reactions forming in the main chain of the macromolecule a linkage containing nitrogen [5]

|  | D21H 17/55 |
· · · · · | Polyamides; Polyaminoamides; Polyester-amides [5]

|  | D21H 17/56 |
· · · · · | Polyamines; Polyimines; Polyester-imides [5]

|  | D21H 17/57 |
· · · · · | Polyureas; Polyurethanes [5]

|  | D21H 17/58 |
· · · · | obtained by reactions forming in the main chain of the macromolecule a linkage containing sulfur [5]

|  | D21H 17/59 |
· · · · | obtained by reactions forming in the main chain of the macromolecule a linkage containing silicon [5]

|  | D21H 17/60 |
· | Waxes [5]

|  | D21H 17/61 |
· | Bitumen [5]

|  | D21H 17/62 |
· | Rosin; Derivatives thereof [5]

|  | D21H 17/63 |
· | Inorganic compounds [5]

|  | D21H 17/64 |
· · | Alkaline compounds [5]

|  | D21H 17/65 |
· · | Acid compounds [5]

|  | D21H 17/66 |
· · | Salts, e.g. alums [5]

|  | D21H 17/67 |
· · | Water-insoluble compounds, e.g. fillers, pigments [5]

|  | D21H 17/68 |
· · · | siliceous, e.g. clays [5]

|  | D21H 17/69 |
· · · | modified, e.g. by association with other compositions prior to incorporation in the pulp or paper [5]

|  | D21H 17/70 |
· · | forming new compounds in situ, e.g. within the pulp or paper, by chemical reaction with other substances added separately [5]

P:0 |  | D21H 19/00 |
Coated paper (coated fibreboard Fulltext... Hierarchy... Expanded...D21J 1/08); Coating material (recording sheets characterised by the coating used to improve ink, dye or pigment receptivity Fulltext... Hierarchy... Expanded...B41M 5/50) [5]

|  | D21H 19/02 |
· | Metal coatings (Fulltext... Hierarchy... Expanded...D21H 19/66 takes precedence) [5]

|  | D21H 19/04 |
· · | applied as foil [5]

|  | D21H 19/06 |
· · | applied as liquid or powder [5]

|  | D21H 19/08 |
· · | applied as vapour, e.g. in vacuum [5]

|  | D21H 19/10 |
· | Coatings without pigments (Fulltext... Hierarchy... Expanded...D21H 19/66 takes precedence) [5]

|  | D21H 19/12 |
· · | applied as a solution using water as the only solvent, e.g. in the presence of acid or alkaline compounds [5]

|  | D21H 19/14 |
· · | applied in a form other than the aqueous solution defined in group Fulltext... Hierarchy... Expanded...D21H 19/12 [5]

|  | D21H 19/16 |
· · · | comprising curable or polymerisable compounds (Fulltext... Hierarchy... Expanded...D21H 19/24 takes precedence) [5]

|  | D21H 19/18 |
· · · | comprising waxes [5]

|  | D21H 19/20 |
· · · | comprising macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds [5]

|  | D21H 19/22 |
· · · · | Polyalkenes, e.g. polystyrene [5]

|  | D21H 19/24 |
· · · | comprising macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds [5]

|  | D21H 19/26 |
· · · · | Aminoplasts [5]

|  | D21H 19/28 |
· · · · | Polyesters [5]

|  | D21H 19/30 |
· · · · | Polyamides; Polyimides [5]

|  | D21H 19/32 |
· · · · | obtained by reactions forming a linkage containing silicon in the main chain of the macromolecule [5]

|  | D21H 19/34 |
· · · | comprising cellulose or derivatives thereof [5]

|  | D21H 19/36 |
· | Coatings with pigments (Fulltext... Hierarchy... Expanded...D21H 19/66 takes precedence; metal powder Fulltext... Hierarchy... Expanded...D21H 19/06) [5]

|  | D21H 19/38 |
· · | characterised by the pigments [5]

|  | D21H 19/40 |
· · · | siliceous, e.g. clays [5]

|  | D21H 19/42 |
· · · | at least partly organic [5]

|  | D21H 19/44 |
· · | characterised by the other ingredients, e.g. the binder or dispersing agent [5]

|  | D21H 19/46 |
· · · | Non-macromolecular organic compounds [5]

|  | D21H 19/48 |
· · · · | Diolefins, e.g. butadiene; Aromatic vinyl monomers, e.g. styrene; Polymerisable unsaturated acids or derivatives thereof, e.g. acrylic acid [5]

|  | D21H 19/50 |
· · · | Proteins [5]

|  | D21H 19/52 |
· · · | Cellulose; Derivatives thereof [5]

|  | D21H 19/54 |
· · · | Starch [5]

|  | D21H 19/56 |
· · · | Macromolecular organic compounds or oligomers thereof obtained by reactions only involving carbon-to-carbon unsaturated bonds [5]

|  | D21H 19/58 |
· · · · | Polymers or oligomers of diolefins, aromatic vinyl monomers or unsaturated acids or derivatives thereof [5]

|  | D21H 19/60 |
· · · · | Polyalkenylalcohols; Polyalkenylethers; Polyalkenylesters [5]

|  | D21H 19/62 |
· · · | Macromolecular organic compounds or oligomers thereof obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds [5]

|  | D21H 19/64 |
· · · | Inorganic compounds [5]

|  | D21H 19/66 |
· | Coatings characterised by a special visual effect, e.g. patterned, textured (marbled paper Fulltext... Hierarchy... Expanded...D21H 27/04) [5]

|  | D21H 19/68 |
· · | uneven, broken, discontinuous [5]

|  | D21H 19/70 |
· · | with internal voids, e.g. bubble coatings [5]

|  | D21H 19/72 |
· | Coated paper characterised by the paper substrate [5]

|  | D21H 19/74 |
· · | the substrate having an uneven surface, e.g. crêped or corrugated paper [5]

|  | D21H 19/76 |
· · | the substrate having specific absorbent properties [5]

|  | D21H 19/78 |
· · · | being substantially impervious to the coating [5]

|  | D21H 19/80 |
· | Paper comprising more than one coating (Fulltext... Hierarchy... Expanded...D21H 19/02 takes precedence) [5]

|  | D21H 19/82 |
· · | superposed [5]

|  | D21H 19/84 |
· · | on both sides of the substrate [5]

P:50 |  | D21H 21/00 |
Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper impregnating or coating material, characterised by its function, form or properties [5]

|  | D21H 21/02 |
· | Agents for preventing deposition on the paper mill equipment, e.g. pitch or slime control (removal of fats, resins, pitch, or waxes Fulltext... Hierarchy... Expanded...D21C 9/08) [5]

|  | D21H 21/04 |
· · | Slime-control agents [5]

|  | D21H 21/06 |
· | Paper forming aids [5]

|  | D21H 21/08 |
· · | Dispersing agents for fibres [5]

|  | D21H 21/10 |
· · | Retention agents or drainage improvers [5]

|  | D21H 21/12 |
· · | Defoamers [5]

|  | D21H 21/14 |
· | characterised by function or properties in or on the paper (Fulltext... Hierarchy... Expanded...D21H 19/66, Fulltext... Hierarchy... Expanded...D21H 27/02 take precedence) [5]

|  | D21H 21/16 |
· · | Sizing or water-repelling agents [5]

|  | D21H 21/18 |
· · | Reinforcing agents [5]

|  | D21H 21/20 |
· · · | Wet strength agents [5]

|  | D21H 21/22 |
· · | Agents rendering paper porous, absorbent or bulky [5]

|  | D21H 21/24 |
· · · | Surfactants [5]

|  | D21H 21/26 |
· · | Agents rendering paper transparent or translucent [5]

|  | D21H 21/28 |
· · | Colorants [5]

|  | D21H 21/30 |
· · | Luminescent or fluorescent substances, e.g. for optical bleaching (Fulltext... Hierarchy... Expanded...D21H 21/40 takes precedence) [5]

|  | D21H 21/32 |
· · | Bleaching agents (bleaching cellulose pulp Fulltext... Hierarchy... Expanded...D21C 9/10) [5]

|  | D21H 21/34 |
· · | Ignifugeants [5]

|  | D21H 21/36 |
· · | Biocidal agents, e.g. fungicidal, bactericidal, insecticidal agents [5]

|  | D21H 21/38 |
· · | Corrosion-inhibiting agents or anti-oxidants [5]

|  | D21H 21/40 |
· · | Agents facilitating proof of genuineness or preventing fraudulent alteration, e.g. for security paper (watermarking Fulltext... Hierarchy... Expanded...B41M 3/10, Fulltext... Hierarchy... Expanded...D21F 1/44; security printing Fulltext... Hierarchy... Expanded...B41M 3/14; securities or banknotes characterised by colour effects Fulltext... Hierarchy... Expanded...B44F 1/12; testing paper currency or valuable papers for genuineness Fulltext... Hierarchy... Expanded...G07D 7/00) [5]

|  | D21H 21/42 |
· · · | Ribbons or strips (filaments Fulltext... Hierarchy... Expanded...D21H 15/06) [5]

|  | D21H 21/44 |
· · · | Latent security elements, i.e. detectable or becoming apparent only by use of special verification or tampering devices or methods [5]

|  | D21H 21/46 |
· · · · | Elements suited for chemical verification or impeding chemical tampering, e.g. by use of eradicators [5]

|  | D21H 21/48 |
· · · · | Elements suited for physical verification, e.g. by irradiation [5]

|  | D21H 21/50 |
· | characterised by form (Fulltext... Hierarchy... Expanded...D21H 19/66, Fulltext... Hierarchy... Expanded...D21H 21/42, Fulltext... Hierarchy... Expanded...D21H 27/02 take precedence) [5]

|  | D21H 21/52 |
· · | Additives of definite length or shape [5]

|  | D21H 21/54 |
· · · | being spherical, e.g. microcapsules, beads [5]

|  | D21H 21/56 |
· · | Foam [5]

P:70 |  | D21H 23/00 |
Processes or apparatus for adding material to the pulp or to the paper (applying liquids or other fluent material to surfaces, in general Fulltext... Hierarchy... Expanded...B05; processes for making continuous lengths of paper Fulltext... Hierarchy... Expanded...D21F 11/00) [5]

|  | D21H 23/02 |
· | characterised by the manner in which substances are added [5]

|  | D21H 23/04 |
· · | Addition to the pulp; After-treatment of added substances in the pulp [5]

|  | D21H 23/06 |
· · · | Controlling the addition [5]

|  | D21H 23/08 |
· · · · | by measuring pulp properties, e.g. zeta potential, pH [5]

|  | D21H 23/10 |
· · · · · | at least two kinds of compounds being added [5]

|  | D21H 23/12 |
· · · · | by measuring properties of the formed web [5]

|  | D21H 23/14 |
· · · · | by selecting point of addition or time of contact between components [5]

|  | D21H 23/16 |
· · · · · | Addition before or during pulp beating or refining (disintegrating fibrous raw materials in mills in the presence of chemical agents Fulltext... Hierarchy... Expanded...D21B 1/16; methods of beating Fulltext... Hierarchy... Expanded...D21D 1/02; methods of refining Fulltext... Hierarchy... Expanded...D21D 1/20) [5]

|  | D21H 23/18 |
· · · · · | Addition at a location where shear forces are avoided before sheet-forming, e.g. after pulp beating or refining [5]

|  | D21H 23/20 |
· · · | Apparatus therefor [5]

|  | D21H 23/22 |
· · | Addition to the formed paper [5]

|  | D21H 23/24 |
· · · | during paper manufacture [5]

|  | D21H 23/24 |
Note(s) Processes or apparatus used for addition to the paper during its manufacture, i.e. on-machine, are classified in group Fulltext... Hierarchy... Expanded...D21H 23/24 if they are specially influenced by, or specially adapted to, the paper-making process. [5]

|  | D21H 23/26 |
· · · · | by selecting point of addition or moisture content of the paper [5]

|  | D21H 23/28 |
· · · · · | Addition before the dryer section, e.g. at the wet end or press section [5]

|  | D21H 23/30 |
· · · | Pretreatment of the paper (Fulltext... Hierarchy... Expanded...D21H 23/70, Fulltext... Hierarchy... Expanded...D21H 23/76 take precedence) [5]

|  | D21H 23/32 |
· · · | by contacting paper with an excess of material, e.g. from a reservoir or in a manner necessitating removal of applied excess material from the paper (Fulltext... Hierarchy... Expanded...D21H 23/66 takes precedence; removing excess material Fulltext... Hierarchy... Expanded...D21H 25/08) [5]

|  | D21H 23/34 |
· · · · | Knife or blade type coaters [5]

|  | D21H 23/36 |
· · · · · | Knife or blade forming part of the fluid reservoir, e.g. puddle-type trailing blade [5]

|  | D21H 23/38 |
· · · · · | the fluid material being applied with a special device, e.g. with a roll in a flooded-nip inverted blade coater [5]

|  | D21H 23/40 |
· · · · | only one side of the paper being in contact with the material (Fulltext... Hierarchy... Expanded...D21H 23/34 takes precedence) [5]

|  | D21H 23/42 |
· · · · | Paper being at least partly surrounded by the material on both sides (Fulltext... Hierarchy... Expanded...D21H 23/34 takes precedence) [5]

|  | D21H 23/44 |
· · · · · | Treatment with a gas or vapour [5]

|  | D21H 23/46 |
· · · | Pouring or allowing the fluid to flow in a continuous stream on to the surface, the entire stream being carried away by the paper (Fulltext... Hierarchy... Expanded...D21H 23/66 takes precedence) [5]

|  | D21H 23/48 |
· · · · | Curtain coaters [5]

|  | D21H 23/50 |
· · · | Spraying or projecting (Fulltext... Hierarchy... Expanded...D21H 23/44, Fulltext... Hierarchy... Expanded...D21H 23/66 take precedence) [5]

|  | D21H 23/52 |
· · · | by contacting paper with a device carrying the material (Fulltext... Hierarchy... Expanded...D21H 23/32, Fulltext... Hierarchy... Expanded...D21H 23/46, Fulltext... Hierarchy... Expanded...D21H 23/66 take precedence) [5]

|  | D21H 23/54 |
· · · · | Rubbing devices, e.g. brush, pad, felt [5]

|  | D21H 23/56 |
· · · · | Rolls (Fulltext... Hierarchy... Expanded...D21H 23/38 takes precedence) [5]

|  | D21H 23/58 |
· · · · · | Details thereof, e.g. surface characteristics, peripheral speed [5]

|  | D21H 23/60 |
· · · · · · | the material on the applicator roll being subjected to a particular treatment before applying to the paper (Fulltext... Hierarchy... Expanded...D21H 23/64 takes precedence) [5]

|  | D21H 23/62 |
· · · · · · | Reverse roll coating, i.e. applicator roll surface moving in direction opposite to that of the paper [5]

|  | D21H 23/64 |
· · · · | the material being non-fluent at the moment of transfer, e.g. in form of preformed, at least partially hardened coating [5]

|  | D21H 23/66 |
· · · | Treating discontinuous paper, e.g. sheets, blanks, rolls [5]

|  | D21H 23/68 |
· · · · | whereby the paper moves continuously [5]

|  | D21H 23/70 |
· · · | Multistep processes; Apparatus for adding one or several substances in portions or in various ways to the paper, not covered by another single group of this main group [5]

|  | D21H 23/72 |
· · · · | Plural serial stages only [5]

|  | D21H 23/74 |
· · · · | Apparatus permitting switching from one technique to another [5]

|  | D21H 23/76 |
· | characterised by choice of auxiliary compounds which are added separately from at least one other compound, e.g. to improve the incorporation of the latter or to obtain an enhanced combined effect (Fulltext... Hierarchy... Expanded...D21H 17/18, Fulltext... Hierarchy... Expanded...D21H 17/70, Fulltext... Hierarchy... Expanded...D21H 23/10 take precedence) [5]

|  | D21H 23/78 |
· | Controlling or regulating not limited to any particular process or apparatus [5]

P:80 |  | D21H 25/00 |
After-treatment of paper not provided for in groups Fulltext... Hierarchy... Expanded...Fulltext... Hierarchy... Expanded...D21H 17/00-D21H 23/00 [5]

|  | D21H 25/02 |
· | Chemical or biochemical treatment (Fulltext... Hierarchy... Expanded...D21H 25/18 takes precedence) [5]

|  | D21H 25/04 |
· | Physical treatment, e.g. heating, irradiating (Fulltext... Hierarchy... Expanded...D21H 25/18 takes precedence; dryer section of machines for making continuous webs of paper Fulltext... Hierarchy... Expanded...D21F 5/00) [5]

|  | D21H 25/06 |
· · | of impregnated or coated paper (Fulltext... Hierarchy... Expanded...D21H 25/08 takes precedence) [5]

|  | D21H 25/08 |
· | Rearranging applied substances, e.g. metering, smoothing; Removing excess material [5]

|  | D21H 25/10 |
· · | with blades [5]

|  | D21H 25/12 |
· · | with an essentially cylindrical body, e.g. roll or rod [5]

|  | D21H 25/14 |
· · · | the body being a casting drum [5]

|  | D21H 25/16 |
· · | with a blast of vapour or gas, e.g. air knife [5]

|  | D21H 25/18 |
· | of old paper as in books, documents, e.g. restoring [5]

P:40 |  | D21H 27/00 |
Special paper not otherwise provided for, e.g. made by multi-step processes [5]

|  | D21H 27/00 |
Note(s) This group provides for the classification of paper with special properties or applications which are only partially or not at all provided for elsewhere in the classification. Whenever possible, however, these papers are classified according to the criteria used in the other groups of this subclass. [5]

|  | D21H 27/02 |
· | Patterned paper (patterned coatings Fulltext... Hierarchy... Expanded...D21H 19/66; embossing Fulltext... Hierarchy... Expanded...B31F 1/07; prepared on the paper-making machines Fulltext... Hierarchy... Expanded...D21F 11/00) [5]

|  | D21H 27/04 |
· · | marbled [5]

|  | D21H 27/06 |
· | Vegetable or imitation parchment; Glassine paper [5]

|  | D21H 27/08 |
· | Filter paper (self-supporting filtering material Fulltext... Hierarchy... Expanded...B01D 39/14; making on paper-making machines Fulltext... Hierarchy... Expanded...D21F 11/14) [5]

|  | D21H 27/10 |
· | Packing paper (packaging materials of special type or form Fulltext... Hierarchy... Expanded...B65D 65/38) [5]

|  | D21H 27/12 |
· | Electrically-insulating paper [5]

|  | D21H 27/14 |
· | Paper having stable form or dimension; Curl-resistant paper (anticoil photographic support Fulltext... Hierarchy... Expanded...G03C 1/81) [5]

|  | D21H 27/16 |
· | Pure paper, i.e. paper lacking or having low content of contaminants (after-treatment of cellulose pulp Fulltext... Hierarchy... Expanded...D21C 9/00) [5]

|  | D21H 27/18 |
· | Paper- or board-based structures for surface covering [5]

|  | D21H 27/20 |
· · | Flexible structures being applied by the user, e.g. wallpaper (printed wallpapers Fulltext... Hierarchy... Expanded...B41M 3/18; paperhanging Fulltext... Hierarchy... Expanded...B44C 7/00; pregummed wallpaper Fulltext... Hierarchy... Expanded...C09J 7/04) [5]

|  | D21H 27/22 |
· · | Structures being applied on the surface by special manufacturing processes, e.g. in presses [5]

|  | D21H 27/24 |
· · · | characterised by the surface to be covered being phenolic-resin paper laminates, vulcan fibre or similar cellulosic fibreboards [5]

|  | D21H 27/26 |
· · · | characterised by the overlay sheet or the top layers of the structures (decorative panels Fulltext... Hierarchy... Expanded...B44C 5/04; wood grain effects Fulltext... Hierarchy... Expanded...B44F 9/02) [5]

|  | D21H 27/28 |
· · · · | treated to obtain specific resistance properties, e.g. against wear or weather (water-repelling agents Fulltext... Hierarchy... Expanded...D21H 21/16) [5]

|  | D21H 27/30 |
· | Multi-ply (for surface covering Fulltext... Hierarchy... Expanded...D21H 27/18; making on paper-making machines Fulltext... Hierarchy... Expanded...D21F 9/00, Fulltext... Hierarchy... Expanded...D21F 11/00) [5]

|  | D21H 27/30 |
Note(s) Layered products classified in this group are also classified in subclass Fulltext... Hierarchy... Expanded...B32B. [5]

|  | D21H 27/32 |
· · | with materials applied between the sheets (attaching together paper or cardboard sheets Fulltext... Hierarchy... Expanded...B31F 5/00; adhesives Fulltext... Hierarchy... Expanded...C09J) [5]

|  | D21H 27/34 |
· · · | Continuous materials, e.g. filaments, sheets, nets [5]

|  | D21H 27/36 |
· · · · | Films made from synthetic macromolecular compounds [5]

|  | D21H 27/38 |
· · | at least one of the sheets having a fibrous composition differing from that of other sheets [5]

|  | D21H 27/40 |
· · | at least one of the sheets being non-planar, e.g. crêped (creping or corrugating paper Fulltext... Hierarchy... Expanded...B31F) [5]

|  | D21H 27/42 |
· · | comprising dry-laid paper [5]