Abstract: Provided are a vibrating body for speaker device which prevents interlayer from peeling in advance and includes a large effective vibration area, and a speaker device including this vibrating body for speaker device. The vibrating body for speaker device includes a first interlaced fiber member, and a second interlaced fiber member which overlaps with the first interlaced fiber member, and one of the first interlaced fiber member and the second interlaced fiber member includes polyvinyl alcohol fibers containing boron, and an outer circumferential portion of the first interlaced fiber member is larger than an outer circumferential portion of the second interlaced fiber member.

Abstract: A diaphragm can be obtained which exhibits large internal loss and Young's modulus and which can be produced efficiently. A speaker diaphragm 1 comprises at least one layer 1A formed by molding a component member configured by a fiber and a tangled fiber body of a synthetic fiber. The synthetic fiber is a polyvinyl alcohol fiber having boron.

Abstract: Provided are a vibrating body for speaker device which prevents interlayer from peeling in advance and includes a large effective vibration area, and a speaker device including this vibrating body for speaker device. The vibrating body for speaker device includes a first interlaced fiber member, and a second interlaced fiber member which overlaps with the first interlaced fiber member, and one of the first interlaced fiber member and the second interlaced fiber member includes polyvinyl alcohol fibers containing boron, and an outer circumferential portion of the first interlaced fiber member is larger than an outer circumferential portion of the second interlaced fiber member.

Abstract: Provided is an inexpensive speaker diaphragm which can suppress inter-layer peeling. A speaker diaphragm includes a first diaphragm layer and a second diaphragm layer which are respectively configured by sheet-forming bodies of materials and stacked to each other, and the first diaphragm layer and the second diaphragm layer are integrally formed in a boundary portion.

Abstract: A polyimide film F is brought into an intimate contact with a molding die 3 having a concave molding surface 3a so as to tightly close the open end thereof, and the polyimide film F is bent to deform only by the pressure difference of gas while being heated in a contactless manner. Molding is conducted by applying depressurization for a space 8 on the side of the molding die 3 relative to the polyimide film F while pressurizing the space 9 on the opposite side for the pressure difference at least in the final stage of the bending deformation so as to be in intimate contact with the concave molding surface 3a.