Sekisui Chemical Co., Ltd.

Nobuto Kamiya

Tetsuhiro Kato

Yuuta Katsurayama

Yasuyuki Shirasaka

Masahiro Tsuchiya

Bungo Hatta

Takazumi Okabayashi

Kazuyoshi Iwane

Ryousuke Takahashi

Akihiko Bandou

Naoyuki Morimoto

Junji Shibayama

Kiyoshirou Narimatsu

Yoshiaki Tamai

Youhei Takanohashi

A pressure-sensitive adhesive tape () has a base material (), and a pressure-sensitive adhesive layer () provided on the surface (A) of the base material () and containing cells () in the inside thereof, wherein the cells () include first cells (A) contacting with the surface (A) of the base material () and second cells (B) disposed at positions away from the surface (A) of the base material (). Thereby, even when the cells () are made to be much contained in the pressure-sensitive adhesive layer () and the amount of a pressure-sensitive adhesive is made small, a high pressure-sensitive adhesive performance of the pressure-sensitive adhesive tape () is retained.

Adhesive tape and method for producing same

The present invention provides an electret sheet that has excellent durability against a pressing force that is repetitively applied, that is, excellent compression recovery properties, and can suppress stuffiness even when used by attaching it to the skin of a human body. The electret sheet of the present invention has an air permeability of 10 to 1,000 sec/100 mL. Thus, the electret sheet has excellent durability against a pressing force that is repetitively applied, that is, excellent compression recovery properties, and can suppress stuffiness even when used by attaching it to the skin of a human body.

Electret sheet and piezoelectric sensor

The present invention provides an electret sheet that exhibits excellent piezoelectricity even by light stress. The electret sheet of the invention is characterized by including a charged porous sheet, in which the electret sheet has a compressive elastic modulus of 80 to 300 MPa when compressively deformed at 25&#xb0; C. and a 50% compression stress of 120 to 300 kPa at 25&#xb0; C., and thus has the excellent piezoelectricity for light stress and exhibits the excellent piezoelectricity even by light stress (0.5N or less) caused by a pulse wave or a breathing.

Electret sheet

The present invention provides a piezoelectric sensor that has elastic properties in a surface direction thereof, and can smoothly follow stretching of a body to be measured to accurately measure movement of the body to be measured, and detect movement in a surface direction of a surface of the body to be measured on which the piezoelectric sensor is disposed. The piezoelectric sensor of the present invention includes: a piezoelectric sheet including a porous synthetic resin sheet; a signal electrode layer that is layered on a surface of the piezoelectric sheet and contains conductive fine particles and a binder resin having elastic properties; and a ground electrode layer that is layered on another surface of the piezoelectric sheet and contains conductive fine particles and a binder resin having elastic properties.

Piezoelectric sensor

The present invention provides an electret sheet that exhibits excellent piezoelectricity even by light stress. The electret sheet of the invention is characterized by including a charged porous sheet, in which the electret sheet has a compressive elastic modulus of 80 to 300 MPa when compressively deformed at 25&#xb0; C. and a 50% compression stress of 120 to 300 kPa at 25&#xb0; C., and thus has the excellent piezoelectricity for light stress and exhibits the excellent piezoelectricity even by light stress (0.5 N or less) caused by a pulse wave or a breathing.

The present invention provides an electret sheet that retains high piezoelectricity under high-temperature condition. The electret sheet of the invention is characterized by including a charged porous sheet, in which the electret sheet has a volume resistivity of 1.0&#xd7;10&#x3a9;&#xb7;cm or more at 25&#xb0; C. and a dielectric breakdown voltage of 7 kV or more at 25&#xb0; C. The electret sheet preferably having a volume resistivity of 1.0&#xd7;10&#x3a9;&#xb7;cm or more at 37&#xb0; C. and a dielectric breakdown voltage of 7 kV or more at 37&#xb0; C. retains excellent piezoelectricity even after being left under a high-temperature atmosphere over a long period.

A piezoelectric sensor including: a piezoelectric sheet; a first ground electrode integrally laminated on a first side of the piezoelectric sheet and having a first cutout section; a signal electrode integrally laminated on a second side of the piezoelectric sheet and having a third cutout section; and a second ground electrode integrally laminated on the signal electrode so as to be electrically insulated from the signal electrode and having a second cutout section. The cutout sections of the signal electrode, the first ground electrode, and the second ground electrode are at least partially overlapped with one another in a thickness direction of the piezoelectric sheet. A portion of the piezoelectric sheet exposed from a portion where the cutout sections of the signal electrode, the first ground electrode, and the second ground electrode are overlapped with one another serves as an exposed section.

Piezoelectric sensor including overlapping cutout sections in a signal electrode, a first ground electrode, and a second electrode

The present invention provides an electret sheet which can maintain a high generated voltage even if a large amount of pressure has been applied. Disclosed is an electret sheet of the present invention including an electrically charged propylene-based resin foam sheet which contains a crosslinked propylene-based resin that includes a propylene-&#x3b1;-olefin random copolymer having a weight average molecular weight of 370,000 to 420,000 at a proportion of 60% by weight or more, and has a gel fraction of 30% to 50% by weight, and in which the average thickness is 90 to 150 &#x3bc;m, and the average number of foam cells in the thickness direction is 2 to 4 cells.

Growing community of inventors

Osaka, Japan

Nobuto Kamiya