Patent ID: 6342289
Filing Date: 2002-01-29
Classification: B41M,Y10T

Abstract:
A recording medium having a porous ink-receiving layer containing alumina hydrate of boehmite structure formed on a base material, said ink-receiving layer formed of a dried coating of a liquid dispersion of said alumina hydrate onto said base material, an amount of said dried coating ranging from 2 to 60 g/m3, and said ink-receiving layer having a total pore volume ranging from 0.1 to 1.0 cm3/g, wherein microcrystals of said alumina hydrate are directed to be parallel to a plane direction of said ink-receiving layer at a parallelization degree of not less than 1.5, wherein the maximum length or the maximum diameter of said microcrystals ranges from 1 to 50 nm, and the parallelization degree is defined by an equation: Parallelizationdegree=Intensity&it;â€ƒ&it;ratio&it;â€ƒ&it;for&it;â€ƒ&it;mediumIntensity&it;â€ƒ&it;ratio&it;â€ƒ&it;for&it;â€ƒ&it;powderwherein Intensity&it;â€ƒ&it;ratiofor&it;â€ƒ&it;medium=Peak&it;â€ƒ&it;intensity&it;â€ƒ&it;for&it;â€ƒ&it;plane&it;â€ƒ&it;(020)&it;â€ƒ&it;of&it;â€ƒ&it;mediumPeak&it;â€ƒ&it;intensity&it;â€ƒ&it;for&it;â€ƒ&it;plane&it;â€ƒ&it;(120)&it;â€ƒ&it;of&it;â€ƒ&it;medium,andIntensity&it;â€ƒ&it;ratiofor&it;â€ƒ&it;powder=Peak&it;â€ƒ&it;intensity&it;â€ƒ&it;for&it;â€ƒ&it;plane&it;â€ƒ&it;(020)&it;â€ƒ&it;of&it;â€ƒ&it;powderPeak&it;â€ƒ&it;intensity&it;â€ƒ&it;for&it;â€ƒ&it;plane&it;â€ƒ&it;(120)&it;â€ƒ&it;of&it;â€ƒ&it;powder;wherein said peak intensities are measured for each of the planes of medium and powder from X-ray diffraction measurements of the ink-receiving layer of the recording medium, and a powder obtained by pulverizing the ink-receiving layer, respectively.