| 摘要 |
PURPOSE:To make it possible to manufacture ink which is suitable for ink jet recording and writing tools, by preparing ink by the use of a dye solution which has previously been hypochlorized by chromatography. CONSTITUTION:A dye powder 22 and pure water (a) are supplied to a mixing tank 24 where they are mixed together such that the powder 22 is dissolved into the water thereby to produce an aqueous dye solution. The solution is passed through a filter 29 to filter out the dye powder particles and others which are not dissolved into the pure water and is then supplied to a supply tank 31. A purifying section 41 is constituted by a plurality of hypochlorizing units 42. In a hypochlorizing filter part 44 in each of the units 42, inorganic salts are removed from the aqueous dye solution and the secondary solution supplied from a supply valve control part 43 by means of chromatography. The aqueous dye solution in which the inorganic salt concentration has been reduced below a predetermined value (e.g., 5wt% with respect to the dye) by such (hypochlorization) purification is discharged to a storage tank 56 through control effected by a discharge valve control part 45. |
