To provide a water-absorptive resin composition having excellent absorbing characteristics such as absorption scale and diffusion absorption scale under pressure, free from agglomeration of particles even under high humidity, and in which surfaces of individual particles are secondarily crosslinked uniformly, and to provide its production process.
The water-absorptive resin composition essentially comprises particulate water-absorptive resin crosslinked in the vicinity of surfaces thereof. The particulate water-absorptive resin comprises ≥95 wt.% of particles having ≥106μm to less than 850μm size where the weight-average particle diameter of the particles is ≥300μm to less than 500μm, and logarithmic standard deviation (σζ) of the particle size distribution of the particles is ≤0.45, and at the same time, the water-soluble content of the water-absorptive resin is ≤35 wt.%. The particulate water-absorptive resin further comprises a multi-valent metal component the extractable content of which is in the range of ≥5 wt.% to less than 100 wt.%. Thereby, the water-absorptive resin composition having excellent absorbing characteristics such as absorption scale and diffusion absorption scale under pressure, free from agglomeration of particles even under high humidity is provided.
KITANO TAKAHIRO
FUJINO SHINICHI
WADA KATSUYUKI
TORII ICHIJI
IWAMURA TAKU
MACHIDA SAYAKA
| JP2001096151A | 2001-04-10 | |||
| JPH09309916A | 1997-12-02 | |||
| JP2001098170A | 2001-04-10 | |||
| JPS63270741A | 1988-11-08 |
| WO2002020068A1 | 2002-03-14 |
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