Loading patent…
AssigneeNippon Shokubai Co., Ltd.
InventorsSei Nakahara, Kunihiko Ishizaki, Hirotama Fujimaru, Yasuhisa Nakashima, Kazuhiko Sakamoto
Estimating the term…
In order to produce inexpensively with high productivity a water-absorbent resin of which: the residual monomer content and the water-extractable content are both low, and the properties are high, and the colorability is low; there is provided a process for producing a water-absorbent resin, which is a process for producing a crosslinked water-absorbent resin by polymerizing a monomer component including acrylic acid and/or its salt in a major proportion wherein the acrylic acid is a product obtained by catalytic gas phase oxidation of propylene and/or propane, with the process being characterized by comprising the steps of: preparing the monomer component from an acrylic acid composition that includes the unneutralized acrylic acid and a methoxyphenol and has a methoxyphenol content of 10 to 160 ppm by weight (based on the unneutralized acrylic acid); and then carrying out radical and/or ultraviolet polymerization of the resultant monomer component.
A process for producing a water-absorbent resin, which is a process for producing a crosslinked water-absorbent resin by polymerizing a monomer component including acrylic acid and/or its salt in a major proportion of the monomer component wherein the acrylic acid is a product obtained by catalytic gas phase oxidation of propylene and/or propane,
A process for producing a water-absorbent resin, which is a process for producing a crosslinked water-absorbent resin by polymerizing a monomer component including acrylic acid and/or its salt in a major proportion wherein the acrylic acid is a product obtained by catalytic gas phase oxidation of propylene and/or propane,
A process for producing a water-absorbent resin, which is a process for producing a crosslinked water-absorbent resin by polymerizing a monomer component including acrylic acid and/or its salt in a major proportion wherein the acrylic acid is a product obtained by catalytic gas phase oxidation of propylene and/or propane,
An acrylic acid composition, comprising unneutralized acrylic acid and being used in producing a crosslinked water-absorbent resin by polymerizing a monomer component including acrylic acid and/or its salt in a major proportion wherein the acrylic acid is a product obtained by catalytic gas phase oxidation of propylene and/or propane,
A process for producing an acrylic acid composition, which is a process for producing an acrylic acid composition comprising unneutralized acrylic acid and being used in producing a crosslinked water-absorbent resin by polymerizing a monomer component including acrylic acid and/or its salt in a major proportion wherein the acrylic acid is a product obtained by catalytic gas phase oxidation of propylene and/or propane,
Dependencies are inferred from the claim text.