3207 40 40 and 3207 40 85 · Glass frit and other glass, in the form of powder, granules or flakes
These subheadings cover:
1. glass frit, i.e., the product obtained by suddenly cooling in water the liquid mass or paste resulting from the fusion of the original components of glass. These components include, for example, silica, sodium carbonate, magnesium carbonate, barium carbonate, potassium carbonate, calcium carbonate, sodium sulphate, potassium sulphate, sodium nitrate, potassium nitrate, lead oxides (litharge and red lead), kaolin, feldspar, borax and boric acid.
Glass frit of these subheadings is used principally for the preparation of vitrifiable compositions. It can be distinguished from the frits of subheadings 3207 20 10 and 3207 20 90 by the fact that it does not contain pigments, opacifiers or oxides facilitating the adherence of the coating to metallic surfaces, and that it produces, after heat vitrification, a surface more or less transparent but not uniformly opaque or coloured;
2. powder and granules of glass obtained by crushing and grinding broken and waste glassware. These products, as well as certain types of frits of paragraph 1 above, are used in the preparation of abrasive papers and cloths, are sintered to form discs, plates, tubes, etc. and employed for various laboratory purposes;
3. ‘enamel glass’ in the form of powder, granules, etc. which is a special glass used for the ornamentation of glass articles. Normally it melts between 540 and 600 °C in a transparent mass, generally coloured. When in bulk it falls in heading 7001 00, when in bars, rods or tubes it falls in subheading 7002 20 90 or 7002 39 00;
4. glass in flakes, whether coloured or silvered, used for decoration and obtained by crushing small spherical bubbles of blown glass;
5. vitrite, also known as foam glass, in powder or granules obtained from a white, grey or black spongy mass, depending on the impurities which it contains, and used principally for the manufacture of electrical insulators (for example, bases of electrical bulbs).
These subheadings do not cover glass-microspheres for coating cinema screens, electronic display panels, etc. (subheading 7018 20 00).