| 摘要 |
<p>PURPOSE:To continuously prepare ink of stable quality by detecting and controlling the concentrations of dye and inorganic salts in a dye solution in the manufacture of an ink for ink jet recording. CONSTITUTION:A dye powder 22 and pure water are mixed by a stirrer 27 in a compounding tank 24 and filtered through a filter 29 to remove indissolved dye particles, and the solution is supplied through a supply tank 31 to the desalting tank 42 of a purifying section 41. The aqueous dye solution is homogenized by a stirrer 45, and when the concentration of inorganic salts detected by a detector 46 exceeds a given value, the solution is circulated by a pump 48 through a desalting filter 43 consisting of an osmotic filter, etc., to remove the inorganic salts into a salt discharging tank 44. The concentration of dye in the solution is detected hy a detector 47 using a photospectroscopic method, etc., and when the concentration of dye exceeds a given value, pure water is added to the solution through a valve 49. The aqueous dye solution thus obtained is sent to a compounding tank through a storage tank 55 and mixed with a water-soluble organic solvent and additives to prepare a desired ink.</p> |
