| 摘要 |
<p>A method of producing a tobacco-smoke filter comprises mixing a powdered or granular tobacco-smoke filter material with a powdered or granular, low-melting, salt (i.e. a salt with a melting point below 250 DEG C. and preferably between 100 DEG and 150 DEG C.) and heating the mixture to cause the particles of the filter material to become bonded by the salt. The particle sizes of the materials are preferably between 20 and 50 mesh (British Standard) and the bonding salt constitutes 25-50% of the mixture. The filter material may be charcoal, silica gel, zeolites, perlite, sepiolite, activated alumina, magnesium silicate or mixtures thereof. Suitable bonding salts include trisodium orthophosphate, sodium perborate, calcium bromide, aluminium bromide, ferrous sulphate, cupric nitrate, soda alum, potash alum, potassium chrome alum, magnesium stearate, aluminium stearate and crystalline hydrated magnesium acetate. A quantitative example is given using granular carbon and hydrated trisodium orthophosphate. The filters may be prepared by the apparatus described in Specification 1,103,822.</p> |
