| 摘要 |
PROBLEM TO BE SOLVED: To obtain the subject ink follower that can minimally suppress oil phase separation and can be readily given with improved reproducibility by adding a thickener to a base oil with a specific viscosity, then admixing a base oil of high viscosity. SOLUTION: (A) A base oil having a viscosity of <=1 Pa.sec. at 25 deg.C is mixed with (B) a thickener and they are extremely highly homogenized. Then, (C) a base oil of high viscosity is added to the homogenized product to adjust the viscosity of the base oil thereby giving the objective ink follower. An ink cartridge tube 10 is directly filled with a water-based ink 20 and the ink follower 30 is placed in the cartridge tube and a strong centrifugal force is applied from the tail end toward the head of the pen 40 by means of a centrifugal separator whereby the ink 20 and the ink follower can be filled in the cartridge tube 10 without air remaining between them. The component A is preferably mineral oil or silicone oil and the component B is preferably a fine-particle type thickener as silica, alumina, titanium oxide and the like or a synthetic or natural smectite clay thickener. |
