To provide a production method of a water absorbing resin having excellent properties which surpress an increase of a soluble portion in the production process subject to heating such as drying or surface treatment or the like, and also have high absorption ratio in applying to a sanitary use or the like, by improving crosslinking agents capable of adjusting the crosslinking density of the water absorbing resin.
The production method of the water absorbing resin is characterized by applying a crosslinking agent having an oxazoline group, which is the molecular weight of 20 or more, and/or the crosslinking agent having an oxazoline and an unsaturated group, as the internal crosslinking agent which applies the polymer of the unsaturated monomer as a principal chain.
AZUMI TAKASHI
KANAIDA KENTA
