| 摘要 |
PROBLEM TO BE SOLVED: To eliminate coating unevenness due to thickening of coating liquid even when alkali is added by preventing change of ink absorptivity with amorphous silica, and providing high printing density, satisfactory ink absorptivity, and strength and water resistance of an ink receptive layer. SOLUTION: A pore volume of an ink receptive layer of the ink jet recording sheet is 0.80 ml/g or more and a pore volume of pores each having a pore size of 5,000 to 50,000 Å is 0.40 ml/g or more. The layer contains amorphous silica of a main component and hydroxide of alkali metal as needed. The silica of pore volume of 0.80 to 2.00 ml/g is provided in a solid state after it is treated to dispersion slurry at pH11. The slurry of the silica has a concentration of 16 to 20%, pH of 6.0 to 11.6, and a viscosity of 40 to 300 cPs. Such a silica is treated to left to stand for under the conditions of heating and/or humidifying at the time of natural aging after the manufacture. |
