A piezoelectric member including metal electrodes with improved adhesiveness to piezoelectric elements is to be provided. A piezoelectric member 102 includes a piezoelectric element 21, and a pair of electrodes 41, 42 respectively formed on a pair of opposing surfaces 21b, 21c of the piezoelectric element 21. The electrodes 41, 42 includes: a base film 41a that is formed on the opposing surfaces 21b, 21c of the piezoelectric element 21 and contains a thiol group; a metal adhesive film 41b formed on the base film 41a; and an electrode film 41c that is formed on the metal adhesive film 41b and is for applying voltage to the piezoelectric element 21. The metal adhesive film 41b is formed with a different material from the electrode film 41c, and has a thickness of 1 to 10 nm.

An ultrasonic transducer of this invention includes a rigid substrate with opening parts extending between bottom and top surfaces, a flexible resin film fixed to the top surface of the substrate to cover the opening parts, and piezoelectric elements fixed to a top surface of the resin film so as to overlap in a plan view with the opening parts, respectively. An arrangement pitch of the piezoelectric elements is preferably set to be equal to or less than 4.3 mm, and the piezoelectric element may have a rectangular shape in the plan view having longitudinal and lateral dimensions in the plan view with a maximum value of 4.0 mm or less, a circular shape in the plan view having a diameter of 4.0 mm or less, or an elliptical shape in the plan view having a major axis of 4.0 mm or less.

A mechanically and piezoelectrically anisotropic polymer thin film is formed from a crystallizable polymer and an additive configured to interact with the polymer to facilitate chain alignment and, in some examples, create a higher crystalline content within the polymer thin film. The polymer thin film and its method of manufacture may be characterized by a bimodal molecular weight distribution where the molecular weight of the additive may be less than approximately 5% of the molecular weight of the crystallizable polymer. Example polymers may include vinylidene fluoride, trifluoroethylene, chlorotrifluoroethylene, hexafluoropropylene, and vinyl fluoride. Example additives may occupy up to approximately 60 wt. % of the polymer thin film. The polymer thin film may be characterized by a piezoelectric coefficient (d.sub.31) of at least approximately 5 pC/N or an electromechanical coupling factor (k.sub.31) of at least approximately 0.1.

A polymer thin film includes polyvinylidene fluoride (PVDF) and is characterized by a Young's modulus along an in-plane dimension of at least 4 GPa, an electromechanical coupling factor (k.sub.31) of at least 0.1 at room temperature. A method of manufacturing such a polymer thin film may include forming a polymer composition into a polymer thin film, applying a tensile stress to the polymer thin film along at least one in-plane direction and in an amount effective to induce a stretch ratio of at least approximately 5 in the polymer thin film, and applying an electric field across a thickness dimension of the polymer thin film. Annealing and poling steps may separately or simultaneously accompany and/or follow the act of stretching of the polymer thin film.

A hydrophone may include a first piezoelectric cable including alternating sections of positive polarity and negative polarity, and a second piezoelectric cable including alternating sections of negative polarity and positive polarity. At least a portion of each section of positive polarity of the first piezoelectric cable may be bonded or adhered to at least a portion of a section of negative polarity of the second piezoelectric cable. A method of manufacturing a hydrophone may include winding or coiling a first piezoelectric cable and a second piezoelectric cable at the same time to create a series of wound sections including cables, the wound sections alternating with a series of not wound sections including the cables.

The invention provides a film having a high relative permittivity, a high volume resistivity, and a high breakdown strength. The film has a relative permittivity of 9 or higher at a frequency of 1 kHz and 30° C., a volume resistivity of 5E+15 Ω.Math.cm or higher at 30° C., and a breakdown strength of 500 V/μm or higher.

A curable organopolysiloxane composition is provided. The composition can be easily processed into a film shape and has a high specific dielectric constant, high dielectric breakdown strength, and a low Young's modulus, allowing for a high energy density to be achieved, in addition to having excellent mechanical strength when used as a dielectric layer in a transducer. A fluoroalkyl group-containing curable organopolysiloxane composition, which can be cured by an addition reaction, comprises: an organopolysiloxane containing an alkenyl group and a fluoroalkyl group; an organohydrogen polysiloxane having SiH at both terminals of a molecular chain but not having a fluoroalkyl group; and a linear fluoroalkyl group-containing organohydrogen polysiloxane or a branched fluoroalkyl group-containing organohydrogen polysiloxane having T units.

A mask that exhibits a more improved antibacterial effect by more efficiently expanding and contracting a body of the mask in the periphery of the nose and mouth area of the mask without using a drug such as an antibacterial agent and/or an antiviral agent. The mask includes: a body including a yarn having a potential generating filament; and at least one dart that extends from an edge portion of the body towards a central portion of the body.

Disclosed is a method for manufacturing a laminated piezoelectric composite. The method includes wet-mixing ceramic powder, a polymer binder, a plasticizer and a solvent for 4 to 72 hours so as to generate a mixed slurry, introducing the mixed slurry into a tape casting process so as to prepare a plurality of piezoelectric composite sheets, drying and forming the plurality of piezoelectric composite sheets using a roll-to-roll process so as to prepare the plurality of formed piezoelectric composite sheets, forming internal electrodes on the plurality of piezoelectric composite sheets so as to prepare the plurality of piezoelectric composite sheets having the internal electrodes, laminating and pressing the plurality of piezoelectric composite sheets having the internal electrodes so as to generate a piezoelectric composite sheet laminate having the internal electrodes, and cutting the piezoelectric composite sheet laminate having the internal electrodes into a desired shape and size.

A method for manufacturing a deformation detection sensor that includes: preparing a plurality of thermoplastic resin layers, at least one of which has a main surface on which a conductive member is formed; laminating the plurality of thermoplastic resin layers; after lamination, integrally forming the plurality of thermoplastic resin layers by hot pressing to obtain a laminated body configured so that a transmission line is formed from a first portion of the conductive member and the laminated body; and attaching a piezoelectric film to the laminated body so that a piezoelectric element is formed from a second portion of the conductive member, the laminated body, and the piezoelectric film.