Process for continuous production of water-absorbent resin product

摘要

There is disclosed a process for continuous production of a water-absorbent resin product by which the water-absorbent resin product having high properties can continuously be produced easily and inexpensively with stable constant quality. In addition, there is disclosed a water-absorbent resin product having high properties and being stable in quality. The process comprises the following steps of: (A) measuring a water-absorbent resin by its predetermined property and/or its predetermined component content, wherein the water-absorbent resin comes being continuously produced via a classification step and/or a surface-modifying step; (B) separating a predetermined amount of water-absorbent resin (a) from the water-absorbent resin that comes being continuously produced, wherein the water-absorbent resin (a) is a water-absorbent resin which displays not less than a definite value and/or a water-absorbent resin which displays not more than a definite value as to the predetermined property and/or the predetermined component content in accordance with results of the aforementioned measurement; and (C) mixing at least a portion of the aforementioned separated predetermined amount of water-absorbent resin (a) into a water-absorbent resin that comes being continuously produced via a classification step and/or a surface-modifying step on the same or another production line.

主权项

1. A process for continuous production of a particulate water-absorbent resin product in which a water-absorbent resin is continuously produced via a classification step and a surface-modifying step, said process comprising the steps of:
surface-modifying a water-absorbent resin obtained from the classification step and comprising a water-swellable and substantially water-insoluble crosslinked polymer having a water-extractable component content of 0 to 50 mass %; measuring at least one property of the resulting surface-modified water-absorbent resin where the at least one property is selected from the group consisting of absorption capacity without load, absorption capacity under load, liquid permeability, component content and particle diameter; and changing a production condition in each of a pulverization step, said classification step, and said surface-modifying step in response to the resulting measurement of the at least one property for the resulting surface-modified water-absorbent resin, and to obtain a yield of the water-absorbent resin per line of not less than 20 t (metric tons)/day.