Nippon Shokubai Co., Ltd.

Other

Akiko Mitsuhashi

Kenji Kadonaga

Kazutomo Takahashi

Masazumi Sasabe

Hirotama Fujimaru

Masuji Izubayashi

Koichi Yonemura

Hiroshi Yamazaki

Kozo Nogi

Nobuyuki Harada

Kinya Nagasuna

Motohiro Imura

Masatoshi Yoshida

Hiroki Inoue

Kenji Minami

Katsuhiko Sakamoto

Kazuhisa Hitomi

Takaya Hayashi

The present invention provides: an absorbent structure and an absorbent article, which are excellent in both liquid diffusion ability and liquid storage ability, and which are excellent in the dry feeling and the amount of wet back of the aqueous liquid, and which can realize the thinning and lightening more; and a water-absorbent resin fitly usable for the above absorbent structure and absorbent article. The absorbent structure, according to the present invention, comprises a liquid-diffusing member and a water-absorbent resin, with the absorbent structure being characterized in that when the capillary absorption index of the liquid-diffusing member at a height of 40 cm is referred to as A (A&#x2267;0.10), the capillary absorption index B of the water-absorbent resin at a height of 40 cm satisfies the following equation: B/A&#x2267;0.7 (equation 1).

Absorbent structure, absorbent article, water-absorbent resin, and its production process and evaluation method

A method for the production of a porous cross-linked polymer material by the polymerization of an HIPE containing a cross-linking agent, characterized by the fact at least one species of the cross-linking agent is a compound having a double bond equivalent f not less than 120 g/mol. The cross-linking agent is preferred to be a compound possessed of an alkylene oxide moiety or a vinyl polymer containing not less than two polymerizing double bonds in the molecular unit. Thus, it is made possible to produce a porous cross-linked polymer material excellent in absorbency and flexibility, permit the HIPE to be polymerized in a short time, and therefore improve the efficiency of production.

Method for production of porous cross-linked polymer material

In producing a porous cross-linked polymer by forming a water-in-oil type high internal phase emulsion and subsequently polymerizing the emulsion, a method for the production of a porous cross-linked polymer material which comprises a step of polymerizing a water-in-oil type high internal phase emulsion obtained in the presence of a polyglycerine fatty acid ester. This invention permits an HIPE to be polymerized at a high temperature for the purpose of stabilizing the HIPE and consequently warrants quick production of a porous cross-linked polymer material possessed of an excellent water absorbing property.

An object of this invention is to provide a method for the production of a porous material by polymerizing a water-in-oil type high internal phase emulsion in a briefer time than a conventional technique without impairing the stability of the emulsion. The object of this invention can be accomplished by a method for the production of a porous material comprising a step of polymerizing a water-in-oil type high internal phase emulsion containing a polymerization initiator, wherein the polymerization initiator is a redox type initiator combining a water-soluble oxidizing agent and a reducing agent, the reducing agent is preparatorily added to form the emulsion, and thereafter the water-soluble oxidizing agent is added to the emulsion to polymerize the added emulsion.

Method for production of porous material

Method for production of porous cross-linked polymer

An object of this invention is to provide a method for the production of a porous material by polymerizing a water-in-oil type high internal phase emulsion in a briefer time than a conventional technique without impairing the stability of the emulsion. The object of this invention can be accomplished by a method for the production of a porous material comprising a step of polymerizing a water-in-oil type high internal phase emulsion containing a polymerization initiator, wherein the polymerization initiator is a redox type initiator combining an oil-soluble oxidizing agent and a reducing agent, either of the oil-soluble oxidizing agent or the reducing agent is preparatorily added to form the emulsion, and thereafter the remainder of the reducing agent or the oil-soluble oxidizing agent is added to the emulsion to polymerize the added emulsion.

Water-absorbent resins which are prepared by mixing polysaccharides with amino acids (amino acids and/or polymers of amino acids) and heating the mixture so as to cause a crosslinking reaction therein. Each of the water-absorbent resins has a water-absorbing ratio of not less than 10 g/g with respect to physiologic saline as well as having a rate of biodegradability of not less than 10%. Moreover, its water-absorbing ratio under pressure is not less than 10 ml/g with respect to physiologic saline. The water-absorbing ratio under pressure is measured by using a measuring device that is constituted of a weighing machine, a container, an air-intake pipe, a conduit, a glass filter, and a measuring section. The water-absorbent resins are superior in both water-absorbing capacity and biodegradability, and are capable of maintain their water-absorbing capacity even under pressure.

Water-absorbent resins and manufacturing methods thereof

Growing community of inventors

Sanda, Japan

Akiko Mitsuhashi