Patent ID: 7923081
Filing Date: 2011-04-12
Classification: B41M

Abstract:
1. A recording medium for water-based ink, comprising a paper base and an ink receptive layer formed on a surface of said paper base, the ink receptive layer comprising a porous layer containing an inorganic pigment and also containing a substance reactive with an ink colorant, the recording medium being to be recorded using water-based ink containing the ink colorant, wherein: a droplet of 4 μl distilled water dropped onto a surface of the ink receptive layer is absorbed in a first absorbing stage of absorbing the droplet at a first absorbing speed (V the second absorbing speed (V 2 ) (μl/sec) being higher than 0.01 (μl/sec) and lower than 0.32 (μl/sec), and given that an inflection point from the first to the second absorbing stage is (a), an inflection point from the second to the third absorbing stage is (b), a final point of the third absorbing stage is (c), absorption quantities at the points (a), (b) and (c) are (qa), (qb) and (qc), respectively, and the times up to the points (a), (b) and (c) are (ta), (tb) and (tc), respectively, the absorption quantity (qa) at the inflection point, (a), is not smaller than 1.3 μl and smaller than 2.0 μl, and the absorption quantity (qb) at the inflection point, (b), is not smaller than 2.0 μl and smaller than 2.5 μl, wherein the ink receptive layer has a pH and the paper base has a pH