Toray Industries, Inc.

Masaki Higashi

Masahiro Kimura

Hiroyuki Matsuura

Takao Sasaki

Masakazu Koiwa

Hiroki Tomioka

Koji Nakatsuji

Yoshikazu Yakake

Takafumi Ogawa

Hiroki Minehara

Shunsuke Tabayashi

Takashi Yoshino

Yuta Amano

Ryosuke Okanishi

Hiroaki Tanaka

Tsuyoshi Hamada

Jun Okabe

Kiyohiko Takaya

Hitoshi Yamasaki

The present invention relates to a composite semipermeable membrane including: a support membrane; and a separation functional layer provided on the support membrane, in which the separation functional layer includes a thin membrane, the thin membrane has a fold structure including a plurality of protrusions, an actual length L of the thin membrane per 1 μm length of the support membrane in a cross-sectional direction perpendicular to a membrane surface is 3.0 μm or more, and a thickness of the thin membrane in the protrusion is 15 nm or more.

Composite semipermeable membrane

The present invention relates to a composite semipermeable membrane including: a support membrane; and a separation functional layer provided on the support membrane, in which the separation functional layer includes a thin membrane, the thin membrane has a fold structure including a plurality of protrusions having a height of 10 nm or more, and in the fold structure, a ratio (T100/T25) is less than 0.95, where T25 is a thickness of the thin membrane in a region of 0% to 25% of the height of the protrusion and T100 is a thickness of the thin membrane in a region of 50% to 100% of the height of the protrusion.

The present invention relates to a composite semipermeable membrane including: a support membrane; and a separation functional layer provided on the support membrane, in which the separation functional layer comprises a plurality of protrusions formed of a thin membrane, and at least a part of the plurality of protrusions has a ratio (Wa/Wb) of larger than 1.3 in cross sections at arbitrary ten positions each having a length of 2.0 μm in a membrane surface direction of the support membrane, provided that Wa is a maximum width of the protrusion and Wb is a root width of the protrusion.

An object of the present invention is to provide a composite semipermeable membrane which has a high permeation rate and high salt removal performance and is excellent in terms of performance stability during long-term operation. The composite semipermeable membrane of the present invention includes: a supporting membrane including a substrate and a porous supporting layer; and a separation functional layer disposed on the porous supporting layer, the separation functional layer includes a crosslinked polyamide and a hydrophilic polymer having an acidic group, and in the separation functional layer, a ratio of (molar equivalent of amino groups)/(molar equivalent of amide groups) is 0.18 or less.

Composite semipermeable membrane and method for producing same

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Ehime, Japan

Masaki Higashi