Manufacturing method for narrow-type diaphragm and thin-type diaphragm, speaker-use diaphragm manufactured using same manufacturing method, speaker, electronic apparatus, and movable device

摘要

After beaten, pulp is mixed with a filler to obtain a mixture of the pulp and the filler. Additives are added to the mixture, which is made into pater and then hot-pressed. The filler content of the mixture is in the range of 20 wt % to 80 wt %. After the additives are added, a polymeric viscosity improver with high viscosity is added to produce a narrow diaphragm or a thin compact diaphragm with high aspect ratio. These diaphragms have high rigidity and a wide reproduction frequency range.

主权项

1. A method of manufacturing a narrow diaphragm or a thin diaphragm, the method comprising, in the sequence set forth:
beating pulp; mixing the beaten pulp with a filler so as to form a mixture of the beaten pulp and the filler; adding a paper-strengthening agent and a sizing agent as additives to the mixture; making paper from the mixture containing the additives; and drying the paper by hot-pressing; wherein a content of the filler in the mixture is in a range of 20 wt % to 80 wt %, inclusive, when the mixture is formed; and a polymeric viscosity improver made of a polymeric material having a molecular weight of 5,000,000 or greater, and having a viscosity of 12,000 mPa·s/25° C. or greater is added after the additives are added and before making the paper.