Polybut-1-ene, a copolymer of but-1-ene with ethylene containing by weight 10|% or less of ethylene, or a blend of polybut-1-ene with polyethylene and/or polypropylene containing by weight 10|% or less of polyethylene and/or 25|% or less of polypropylene, in one of the forms mentioned in note|6(b) to this chapter

1. Throughout the Nomenclature the expression 'plastics' means those materials of headings 3901 to 3914 which are or have been capable, either at the moment of polymerisation or at some subsequent stage, of being formed under external influence (usually heat and pressure, if necessary with a solvent or plasticiser) by moulding, casting, extruding, rolling or other process into shapes which are retained on the removal of the external influence. Throughout the Nomenclature any reference to 'plastics' also includes vulcanised fibre. The expression, however, does not apply to materials regarded as textile materials of Section XI. 2. This chapter does not cover: (a) lubricating preparations of heading 2710 or 3403; (b) waxes of heading 2712 or 3404; (c) separate chemically defined organic compounds (Chapter 29); (d) heparin or its salts (heading 3001); (e) solutions (other than collodions) consisting of any of the products specified in headings 3901 to 3913 in volatile organic solvents when the weight of the solvent exceeds 50% of the weight of the solution (heading 3208); stampings of painting foils of heading 3212; (f) organic surface-active agents or preparations of heading 3402; (g) run gums or ester gums (heading 3806); (h) prepared additives for mineral oils (including gasoline) or for other liquids used for the same purposes as mineral oils (heading 3811); (ij) prepared hydraulic fluids based on polyglycols, silicones or other polymers of Chapter 39 (heading 3819); (k) diagnostic or laboratory reagents on a backing of plastics, prepared diagnostic or laboratory reagents whether or not on a backing of plastics (heading 3822); (l) synthetic rubber, as defined for the purposes of Chapter 40, or articles thereof; (m) saddlery or harness (heading 4201) or trunks, suitcases, handbags or other containers of heading 4202; (n) plaits, wickerwork or other articles of Chapter 46; (o) wall coverings of heading 4814; (p) goods of Section XI (textiles and textile articles); (q) articles of Section XII (footwear, headgear, umbrellas); (r) imitation jewellery of heading 7117; (s) articles of Section XVI (machines and mechanical or electrical equipment); (t) parts of aircraft or vehicles of Section XVII; (u) articles of Chapter 90 (optical, medical instruments); (v) articles of Chapter 91 (clocks and watches); (w) articles of Chapter 92 (musical instruments); (x) articles of Chapter 94 (furniture, lamps, prefabricated buildings); (y) articles of Chapter 95 (toys, games, sports requisites); (z) articles of Chapter 96 (miscellaneous manufactured articles).