Derwent Classification System: Polymers and Plastics

Patents that include the following features are selected for inclusion:

Polymers
Synthetic polymers. Selected natural polymers eg rubbers. Modified natural polymers. Polymerisation equipment and polymer work-up.

Fabrication
All processes and equipment for fabricating polymers including extrusion, injection moulding and slush moulding. The production, treatment and use of film, sheet and pipe.

Monomers
All patents relating to the production and purification of usefully polymerisable monomers, either known or shown clearly in the specification. Monomers are additionally covered in Section E.

Additives
Preparation and use of polymerisation catalysts. To be used in polymer processes. Stabilisers, surface-active agents, plasticisers, slip agents, antistatic agents etc for use with polymers

Uses
Wherever specific synthetic polymers or families of polymers are claimed or the specification is clearly concerned with them. Wherever novelty resides in the use of polymers. When the polymer is not specified or can be a range of alternative materials for an application it is not included. Thus the use of rubber (undefined) components for a common application are automatically included.

A1 ADDITION AND NATURAL POLYMERS
A11 Polysaccharides; natural rubber; other natural polymers (only a restricted range of (modified) natural polymers are included. Thus starch would be excluded, but chemically modified starch included).
A12 Polymers of di-and higher olefins; acetylenics; nitroso compounds.
A13 Polymers of aromatic mono-olefins; including polystyrene.
A14 Polymers of other substituted mono-olefins; including PVC, PTFE.
A17 Polymers of unsubstituted aliphatic mono-olefins; including polyethylene.
A18 Addition polymers in general.
A2 CONDENSATION POLYMERS
A21 Epoxides; aminoplasts; phenoplasts.
A23 Polyamides; polyesters. (including polycarbonates, polyesteramides); alkyds; other unsaturated polymers.
A25 Polyurethanes; polyethers.
A26 Other condensation polymers including silicone polymers and polymides (mineral silicates and similar materials would not usually appear in Section A).
A28 Condensation polymers in general.
A3 PROCESSING: GENERAL ADDITIVES AND APPLICATIONS
A31 Preliminary processes.
A32 Polymer fabrication - such as moulding, extrusion, forming, laminating, spinning.
A35 Other processing and general - including vulcanisation, welding of plastics and adhesive processes. Testing.
A41 MONOMERS AND CONDENSANTS These are also included in Section E.
A60 ADDITIVES AND COMPOUNDING AGENTS If the usage is very restricted it may be classified under the individual polymer or process involved.
A8/9 APPLICATIONS
A81 Adhesives and binders - including chipboard.
A82 Coatings, impregnations, polishes - excluding textile finishing.
A83 Clothing, footwear.
A84 Household and office fittings - including carpets and carbon paper.
A85 Electrical applications.
A86 Fancy goods, games, sports, toys.
A87 Textile auxiliaries.
A88 Mechanical engineering and tools eg valves, gears and conveyor belts.
A89 Photographic, laboratory equipment, optical - including electrophotographic, thermographic uses.
A91 Ion-exchange resins, polyelectrolytes.
A92 Packaging and containers - including ropes and nets.
A93 Roads, building, construction flooring.
A94 Semi-finished materials - fibres, films, foams.
A95 Transport - including vehicle parts, tyres and armaments.
A96 Medical, dental, veterinary, cosmetic
A97 Miscellaneous goods not specified elsewhere - including papermaking, gramophone records, detergents, food and oil well applications.