Kuraray Co., Ltd.

Matsushita Electric Industrial Co., Ltd.

Hayami Yoshimochi

Akio Ohmory

Tomoyuki Sano

Masahiro Satoh

Syunpei Naramura

Satoru Kobayashi

Masahiro Sato

Kazuhiko Tanaka

Masao Kawamoto

Kyoichiro Shibatani

Kiyoshi Hirakawa

Akira Kubotsu

Shinya Inada

Masakazu Nishiyama

Makoto Yano

Kiyoo Shimada

Hirofumi Sano

Isao Tokunaga

Takaaki Tanaka

Hirohumi Sano

Izumi Watadani

A fiber of sea-islands phase separation wherein the sea component comprises a vinyl alcohol based polymer with high orientation and great crystallinity and the islands component comprises a water-insoluble cellulose based polymer with excellent absorptivity of alkaline solutions, thermal resistance and heat fusion resistance, and wherein the size of the islands is 0.03 to 10 .mu.m and the strength is 3 g/d or more, is readily disintegrated into a fibril of a diameter of 0.05 to 8 .mu.m when a mechanical stress is imposed onto the fiber wet in water. From the fibril with good hydrophilicity, high strength, great particle captivity and excellent reinforcing performance, and additionally with good absorptivity of alkaline solutions and great thermal resistance and heat fusion resistance, none of the fiber components therein is solubilized during fibrillation. Neither a beating process nor a beating solution causes foaming or environmental pollution. The fibril is extremely useful for use in separator sheets for alkaline batteries, reinforcing fibers of cement slate plates, reinforcing fibers of frictional materials and the like.

Separator for a battery comprising a fibrillatable fiber

Flame-retardant polyvinyl alcohol base fiber

Readily fibrillatable fiber

Easily fibrillatable fiber

By dissolving a vinyl alcohol polymer (A) and an incompatible vinyl polymer (B), preferably an acrylonitrile polymer in a common solvent to prepare a spinning stock solution of a phase separation structure wherein the polymer (B) is present at particle sizes of 2 to 50 .mu.m, and wet spinning or dry-wet spinning the resulting spinning stock solution in a solidifying bath containing a mixture of an organic solvent capable of solidifying both the polymers (A) and (B) and the solvent of the spinning stock solution at a weight ratio of 25/75 to 85/15, thereby drawing the resulting yarn by 8-fold or more, a fiber is provided; and from the fiber can be produced a fibril with good hydrophilicity, a higher strength, and excellent heat fusion resistance, along with excellent wiping performance, filtering performance, micro-particle capturing properties and reinforcing performance, readily, stably and inexpensively.

Fibrillatable fiber of a sea-islands structure

A fiber comprising a vinyl alcohol units-containing polymer, said polymer being modified at the oxygen atoms of its alcoholic hydroxyl groups with a group represented by the following formula I ##STR1## wherein M represents a chelate-forming metal atom and R represents an alkyl group. The fiber has excellent resistance to hot water and wet heat and does not stick, adhere or shrink even when dyed at high temperatures or treated by steam ironing, thus proving to be of markedly high commercial value.

Vinyl alcohol units-containing polymer composite fiber having resistance

High-strength polyvinyl alcohol fiber is provided by extruding a polyvinyl alcohol dope solution through a spinneret into a coagulating bath, the spinneret being located such that substantially only its dope-extruding surface contacts the coagulating bath. This process can produce stably and at a low cost polyvinyl alcohol fibers with excellent strength.

Process of making high-strength polyvinyl alcohol fiber

An electrical circuitry for use in the measurement of the activity of ions in an electrolyte solution carried out by the use of an ion-sensitive field-effect transistor transducer having a gate or ion sensitive layer, a source and a drain. The measurement is carried out by adjusting the drain current flowing through the field-effect transistor to a predetermined value such that the temperature dependency of the electroconductivity of the channel of the transistor becomes equal to the sum of the temperature dependency of the potential at an interface between a reference electrode and the electrolyte solution and the temperature dependency of the potential at an interface between the ion-sensitive layer and the electrolyte solution.

Method and device for compensating temperature-dependent characteristic

Growing community of inventors

Kurashiki, Japan

Hayami Yoshimochi