Alumina hydrate particle, alumina hydrate particle dispersion sol and liquid coating for forming ink-receiving layer and substrate having ink-receiving layer

摘要

Highly transparent alumina hydrate particles having a large pore volume, having a pore diameter which falls in a specified range and, when formed into a high-concentration dispersion sol, exhibiting a low viscosity are provided. Alumina hydrate particles having a composition represented by the general formula xM₂O.y(NH₄)₂O.Al₂O₃.zH₂O (2x10^-4<=x<=25x10^-4, 0.1x10^-4<=y<=20x10^-4, 0.6<=z<=2.5, M represents an alkali metal; when the alkali metal is in the form of M₂O, x is the number of moles thereof per mol of Al₂O₃; when ammonia is in the form of (NH₄)₂O, y is the number of moles thereof per mol of Al₂O₃; and z is the number of moles of hydration water (H₂O) per mol of Al₂O₃), the alumina hydrate particles having an average particle diameter of 0.02 to 0.2 mum, a total pore volume of 0.5 to 1.5 ml/g, and a volume of pores whose diameter is from 15 to 30 nm ranging from 0.3 to 1.0 ml/g.