Unicharm Corporation

Hiroshima University

Ehime Prefectural Government

Uni-charm Corportation

Takayoshi Konishi

Toshio Hiraoka

Naohito Takeuchi

Noritomo Kameda

Kazuya Okada

Hideaki Ichiura

Noritomo Kurita

Koichi Yamaki

Hisashi Takai

Jyoji Shimizu

Toshiyuki Tanio

Masaki Yoshida

Kouichi Yamaki

Takashi Kato

Daisuke Yamada

Masashi Yamaguchi

Masaaki Morikawa

Hiroko Nakaoka

Masaki Takahashi

Noriyoshi Nishida

Takamitsu Igaue

Naoto Ohashi

Toru Oba

Naoyuki Funamizu

Hiroki Gohda

Satoshi Mizutani

Ayami Suga

Masashi Nakashita

Masayoshi Matsumoto

Yoshihide Ishikawa

Takahiro Ueda

Ryuichiro Kurata

Azusa Matsushima

Kiyoko Nishimura

Norihiro Tokita

Hiromi Yamada

Toshifumi Hikosaka

Ken Ushijima

Nowaki Hijikata

Nobuo Morohashi

Hiroki Yoshikawa

Takeshi Bandou

Haruna Onodera

Ryusei Ito

Toshihide Kakizono

Hiroko Nozumi

The purpose of the present invention is to provide a method for producing recycled pulp fibers such that articles using the recycled pulp fibers can easily achieve a uniform whiteness and users are not prone to feel psychological resistance to articles using the recycled pulp fibers. This method is described below. The method is characterized by involving: a step for supplying, from a mixed solution supply port () to a treatment tank (), a mixed solution () which contains superabsorbent polymers and pulp fibers derived from multiple types of used sanitary products; a step for supplying an ozone-containing gas () from an ozone-containing gas supply port () to a treatment solution () inside of the treatment tank (); a step in which, by raising the ozone-containing gas () while lowering the superabsorbent polymers and pulp fibers in the treatment tank (), the ozone-containing gas () is brought into contact with the superabsorbent polymers and the pulp fibers, and the pulp fibers are bleached to form recycled pulp fibers; and a step for discharging the treatment solution () from a treatment solution discharge port (), wherein the recycled pulp fibers have a-ΔYI with respect to a standard white plate.

Method for producing recycled pulp fibers, and recycled pulp fibers

The purpose of the present disclosure is to provide a method for regenerating a highly water-absorbing polymer that has been deactivated by an acid, the method enabling formation of a highly water-absorbing recycled polymer having predetermined water absorption properties. The regeneration method according to the present disclosure is configured as follows. This method regenerates a highly water-absorbing polymer that has been deactivated by an acid into a highly water-absorbing recycled polymer having predetermined water absorption properties. The method includes: a preparation step (S) for preparing a highly water-absorbing polymer which has an acid group and which has been deactivated by an acid; a highly water-absorbing recycled polymer-forming step (S) for adding an alkali metal ion source, which can supply an alkali metal ion, to a regeneration-use aqueous solution that contains the highly water-absorbing polymer that has been deactivated by an acid, and forming the highly water-absorbing recycled polymer in a wet state from the highly water-absorbing polymer that has been deactivated by the acid; and a drying step for drying the highly water-absorbing recycled polymer in a wet state and forming the highly water-absorbing recycled polymer having the predetermined water absorption properties.

Method for regenerating highly water-absorbing polymer, method for producing highly water-absorbing recycled polymer, and use of alkali metal ion source

The purpose of the present invention is to provide a method which is for producing pulp fibers for cellulose nanofiberization from pulp fibers of used sanitary products, and which can produce pulp fibers for cellulose nanofiberization that have low lignin content and a low distribution thereof and that have excellent cellulose nanofiberization properties. This method is described below. The method is characterized by involving: a step for supplying, from a mixed solution supply port () to a treatment tank (), a mixed solution () which contains superabsorbent polymers and pulp fibers derived from used sanitary products; a step for supplying an ozone-containing gas () from an ozone-containing gas supply port () to a treatment solution () inside of the treatment tank (); a step in which, by raising the ozone-containing gas () while lowering the superabsorbent polymers and pulp fibers in the treatment tank (), the ozone-containing gas () is brought into contact with the superabsorbent polymers and the pulp fibers, and pulp fibers for cellulose nanofiberization are formed from the pulp fibers; and a step for discharging the treatment solution () from a treatment solution discharge port (), wherein the pulp fibers for cellulose nanofiberization have a lignin content of less than or equal to 0.1 mass %.

Method for producing pulp fibers for cellulose nanofiberization, and pulp fibers for cellulose nanofiberization

A method of producing conifer-derived pulp fibers for paper includes a beating step of beating conifer-derived material pulp fibers in the presence of a liquid including water; and an ozone treatment step of treating, with ozone water, the beaten conifer-derived material pulp fibers.

Method for producing softwood-derived pulp fibers for paper and softwood-derived pulp fibers for paper

The purpose of the present disclosure is to provide a method for producing pulp fibres for saccharification from the pulp fibres of used sanitary items, said pulp fibres for saccharification having low lignin contents distributed within a narrow range, and enabling the production of pulp fibres for saccharification having superior saccharification properties. The production method according to the present disclosure is characterised by comprising the following: a step for supplying a mixed solution () containing pulp fibres and highly-absorbent polymers sourced from used sanitary items to a treatment tank () via a mixed-solution supply port (); a step for supplying an ozone-containing gas () to a treatment solution () within the treatment tank () via an ozone-containing-gas supply port (); a step for lifting the ozone-containing gas () whilst lowering the pulp fibres and highly-absorbent polymers within the treatment tank (), thereby bringing the ozone-containing gas () into contact with the pulp fibres and highly-absorbent polymers, and forming pulp fibres for saccharification from the pulp fibres; and a step for discharging the treatment solution () via a treatment-solution discharge port (). The method is further characterised in that the pulp fibres for saccharification have lignin contents of 0.1% or less.

Method for producing pulp fibres for saccharification, and aqueous solution of pulp fibres for saccharification

The purpose of the present invention is to provide a method for producing recycled pulp fibers such that articles using the recycled pulp fibers can easily achieve a uniform whiteness and users are not prone to feel psychological resistance to articles using the recycled pulp fibers. This method is described below. The method is characterized by involving: a step for supplying, from a mixed solution supply port () to a treatment tank (), a mixed solution () which contains superabsorbent polymers and pulp fibers derived from multiple types of used sanitary products; a step for supplying an ozone-containing gas () from an ozone-containing gas supply port () to a treatment solution () inside of the treatment tank (); a step in which, by raising the ozone-containing gas () while lowering the superabsorbent polymers and pulp fibers in the treatment tank (), the ozone-containing gas () is brought into contact with the superabsorbent polymers and the pulp fibers, and the pulp fibers are bleached to form recycled pulp fibers; and a step for discharging the treatment solution () from a treatment solution discharge port (), wherein the recycled pulp fibers have a-&#x394;YI with respect to a standard white plate.

Method for producing recycled pulp fibers by decomposing super absorbant polymers with ozone

A method includes producing recycled products from a plurality of used absorbent articles, each including a top sheet, a back sheet and an absorbent body including absorbent body materials, by recovering a plurality of structural members from the plurality of used absorbent articles. At least one of the top sheet and the back sheet includes a film. The method includes: separating the plurality of used absorbent articles into a plurality of the films and the absorbent body materials; sorting the plurality of films into a plurality of types of recyclable films according to the filler contents of the plurality of films; and forming a plurality of types of recycled resin pellets from the plurality of types of recyclable films.

Method for producing recycled product, recycled resin pellet, and recycled film

Provided is a method that, when pulp fibers are recovered from used absorbent articles that have been put into collection bags, makes it possible to safely and sanitarily crush the used absorbent articles while suppressing costs. A method for recovering pulp fibers from used absorbent articles, the method comprising: a crushing step (S) in which collection bags (A) in which used absorbent articles have been sealed are put into a container (), the collection bags in the container are transferred to a crushing device () that communicates with the container, and, bag by bag, the crushing device crushes the used absorbent articles in the collections bags in a deactivating aqueous solution; and a separation step (S) in which the pulp fibers, a highly water-absorbent polymer, and the deactivating aqueous solution are separated from the crushed product and deactivating aqueous solution obtained in the crushing step.

Method and system for recovering pulp fibers from used absorbent articles

Recycled pulp that derives from a used sanitary article includes an antibacterial activity value of 2.0 or more and an acid. Recycled pulp that derives from a used sanitary article includes an antibacterial activity value of 2.0 or more and an ash content of 0.65% by weight or less, and further includes an acid. The acid is a citric acid. The recycled pulp further includes a cationic antibacterial agent. The cationic antibacterial agent is a quaternary ammonium salt. The cationic antibacterial agent is a benzalkonium chloride or a cetylpyridinium chloride. At least a portion of the cationic antibacterial agent is adsorbed on the recycled pulp.

Recycled pulp, absorbent, non-woven fabric, and sanitary article

An absorbent article may include a top sheet that is liquid-permeable, a back sheet that is liquid-impermeable, and an absorbent body situated between the top sheet and the back sheet in a thickness direction. At least one of the top sheet and the back sheet may include a synthetic resin sheet that includes a synthetic resin component and an oxidative decomposer comprising a mixture of a carboxylate and a rare earth compound. The synthetic resin sheet may contain the oxidative decomposer in a mass ratio such that a decomposition rate index (D), as determined by formula (1), is 7.8 or less:&#x2003;&#x2003;(1)where Brepresents a mass ratio (g/g) of the oxidative decomposer with respect to the synthetic resin component, and Srepresents a specific surface area (cm/g) of the synthetic resin sheet.

Absorbent article

A method of recycling superabsorbent polymers derived from a used absorbent article, the method including: treating the superabsorbent polymers with ozone water after inactivation; reactivating, with an alkaline aqueous solution, the superabsorbent polymers treated with the ozone water; and adding hydrophilic fine particles to the superabsorbent polymers reactivated with the alkaline aqueous solution and then drying the superabsorbent polymers.

Method for recycling superabsorbent polymer derived from used absorbent article and recycled superabsorbent polymer derived from used absorbent article

A recycled pulp that is reusable sanitary products is efficiently manufactured by recovering pulp fiber from used sanitary products containing the pulp fiber and a polymer absorbent. The method of the present invention comprises: a step applying a mechanical force to the used sanitary products in an aqueous solution containing a polyvalent metal ion or an acidic aqueous solution with a pH of 2.5 or lower and thus degrading the used sanitary products into the pulp fiber and other materials; a step separating the pulp fiber from the mixture of the pulp fiber and other materials that has been formed in the degradation step; and a step treating the pulp fiber thus separated with an ozone-containing aqueous solution with a pH of 2.5 or lower.

Method for manufacturing recycled pulp from used sanitary products

Provided is a method for producing pulp fibers to be saccharified, whereby it becomes possible to reduce the amount of a highly water-absorbable polymer and therefore increase the collection efficiency in the production of a saccharified solution when pulp fibers for a saccharified liquid is produced from a dirty absorbent article. The method is a method for producing pulp fibers to be saccharified, from pulp fibers in a dirty absorbent article. The method includes: a solid-liquid separation step (S) of crushing up a highly water-absorbable polymer while separating an inactivated aqueous solution containing pulp fibers and the highly water-absorbable polymer both separated from a dirty absorbent article into a solid material () containing the pulp fibers and the highly water-absorbable polymer and a liquid material (E) containing the highly water-absorbable polymer and the inactivated aqueous solution; and a removal step (S) of washing away the remaining highly water-absorbable polymer by washing the separated solid pulp fibers in a solution or another means to produce pulp fibers to be saccharified.

Method for producing pulp fibers to be saccharified

A method of recovering structural members from a used absorbent article comprising a front sheet, a back sheet and an absorbent body between the front sheet and the back sheet, wherein at least one of the front sheet and the back sheet includes a film, and wherein the absorbent body includes an absorbent body material, may include swelling the used absorbent article with water, applying a physical shock to and disintegrating the swelled used absorbent article into at least the film and the absorbent body material, and separating the film and the absorbent body material.

Method for recovering constituent members from used absorbent article

A simple method is provided for producing a saccharified solution from a used absorbent article such as a used diaper. In order to produce a saccharified solution from a used absorbent article comprising a non-cellulosic liquid permeable surface material and an absorbent body that contains pulp fibers, the used absorbent article is immersed, without first being decomposed, in a saccharifying enzyme solution containing cellulase. The pulp fibers in the used absorbent article are saccharified by the cellulase, producing a saccharified solution. The produced saccharified solution is exuded out of the used absorbent article through the liquid permeable surface material, so it is possible to easily separate and recover the saccharified solution from the used absorbent article while maintaining the outer shape.

Method of producing saccharified solution from used absorbent article

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Kagawa, Japan

Takayoshi Konishi