Abstract: In order to suppress the occurrence of damage on a press-fit joining wiring board, a peak value of stress generated on the board in the case of a press-fitting a press-fit terminal into a through-hole is reduced so that it can not exceed the design standard value of the board. In the press-fit terminal in which a body part, retaining part, introducing part and forward end part are integrally formed, a cross-sectional area of the introducing part is reduced to be smaller than that of the retaining part, so that an intensity of the elastic force of the introducing part is decreased to be lower than that of the elastic force of the retaining part. Alternatively, on the wiring board, elastic material is filled into resin for combining sheet-like base material of the board so as to relieve an intensity of stress generated on the board itself.

Abstract: In order to suppress the occurrence of damage on a press-fit joining wiring board, a peak value of stress generated on the board in the case of a press-fitting a press-fit terminal into a through-hole is reduced so that it can not exceed the design standard value of the board. In the press-fit terminal in which a body part, retaining part, introducing part and forward end part are integrally formed, a cross-sectional area of the introducing part is reduced to be smaller than that of the retaining part, so that an intensity of the elastic force of the introducing part is decreased to be lower than that of the elastic force of the retaining part. Alternatively, on the wiring board, elastic material is filled into resin for combining sheet-like base material of the board so as to relieve an intensity of stress generated on the board itself.

Abstract: A glycol dispersion of an inorganic powder is provided, which comprises glycol and an inorganic powder dispersed therein, said inorganic powder being surface-treated with a dispersant having a solubility of not less than 5 (g/100 g-water) in water of 20° C., and which contains water and/or methanol in the specific amounts. According to the present invention, it is not required to transport a slurry of water, methanol or glycol, but possible to transport in the form of powder, so that efficiency in transportation is not only enhanced, but a drastic simplification in the production steps and a cost reduction are attainable because neither a distillation apparatus for replacing a solvent such as water and methanol with glycol nor a step of wet-pulverizing is required. Moreover, a glycol dispersion of the present invention is able to reproduce the excellent shape and size of the inorganic particles before drying or in the initial state and therefore has an excellent dispersibility.

Abstract: A monodisperse spherical, ellipsoidal or plate-like vaterite calcium carbonate almost free from secondary aggregation is disclosed. The vaterite type calcium carbonate is prepared by the steps of adding 5-20 times mol equivalent of water with respect to unslaked lime to a methanol suspension of 0.5-12 weight % of unslaked lime and/or slaked lime (in case of slaked, conversion is to be made into unslaked lime of the same mol) to prepare of a mixture of methanol, unslaked lime and/or slaked lime and water, letting carbon dioxide gas through said mixture, adjusting the temperature in the carbonation reaction system to not less than 30.degree. C. before arrival of conductivity within carbonation reaction system at the maximal point on conductivity variation curve in the carbonation reaction system and adjusting the time from start of carbonation reaction to the point where the conductivity is 100 .mu.S/cm to be less than 1,000 minutes.

Abstract: A monodisperse spherical, ellipsoidal or plate-like vaterite calcium carbonate almost free from secondary aggregation is disclosed. The vaterite type calcium carbonate is prepared by the steps of adding 5-20 times mol equivalent of water with respect to unslaked lime to a methanol suspension of 0.5-12 weight % of unslaked lime and/or slaked lime (in case of slaked, conversion is to be made into unslaked lime of the same mol) to prepare of a mixture of methanol, unslaked lime and/or slaked lime and water, letting carbon dioxide gas through said mixture, adjusting the temperature in the carbonation reaction systemto not less than 30.degree. C. before arrival of conductivity within carbonation reaction system at the maximal point on conductivity variation curve in the carbonation reaction system and adjusting the time from start of carbonation reaction to the point where the conductivity is 100.mu. S/cm to be less than 1,000 minutes.