摘要:
A process for preparing a powdered ceramic raw material comprises the steps of(a) adding ammonia gas or an alkali to a first aqueous solution containing a water-soluble salt of lead capable of being precipitated as a hydroxide until the pH of the first solution reaches a value within the range of 9 to 10 to form a precipitate of lead hydroxide;(b) adding ammonia gas or alkali to a second aqueous solution containing at least one water-soluble salt or ceramic components other than lead capable of being precipitated as a hydroxide until the pH of the second solution reaches a value within the range of 9 to 10 to form a precipitate of hydroxide of said ceramic components;(c) mixing the resulting reaction mixtures, followed by separation of the precipitates of hydroxides from solution, washing with water and drying; and(d) calcining the precipitate to form complex oxides of said ceramic material.
摘要:
A process for preparing a powdered ceramic raw material, comprising the steps of; (a) adding gaseous carbon dioxide or a precipitant composed of a water-soluble carbonate to the first aqueous solution containing at least one nitrate or chloride of elements selected from the group consisting of Ba, Sr, Ca and Mg until the pH of the solution is reached to a predetermined value within the range of 7 to 10 to precipitate at least one carbonate of said elements, (b) adding ammonia gas or a precipitant composed of an aqueous solution of a water-soluble hydroxide to the second aqueous solution of at least one nitrate or choride of elements selected from the group consisting of Ti, Zr and Sn until the pH of the solution is reached to a predetermined value within the range of 7 to 10 to precipitate at least one hydroxide of said elements, (c) adding ammonia gas or a precipitant composed of an aqueous solution of a water-soluble hydroxide to the third aqueous solution of lead acetate or lead nitrate until the pH of the solution is reached to a predetermined value within the range of 7 to 10 to precipitate lead hydroxide, (d) mixing the carbonate precipitated from the first aqueous solution, the hydroxide precipitated from the second solution, and hydroxide precipitated from the third aqueous solution; and (e) treating the resultant mixture with heat to form complex oxides of said elements.
摘要:
A process for preparing a particulate ceramic material comprising the steps of:(a) adding carbon dioxide or an aqueous solution of a soluble carbonate to first aqueous solution of a nitrate or chloride of Ba, Sr, Ca or Mg in a first vessel to adjust the pH of said first aqueous solution to between 7 and 10 thereby forming a carbonate precipitate;(b) adding an aqueous solution of a soluble hydroxide to a second aqueous solution of a nitrate or chloride of Ti, Zr, Sn or Pb in a second vessel to adjust the pH of said second aqueous solution to between 7 and 10 thereby forming a hydroxide precipitate;(c) combining slurries containing the precipitates formed in said first and second vessels;(d) mixing the combined slurries;(e) passing the slurries through a filter;(f) washing the filter cake with water;(g) drying the filter cake to form a powder;(h) calcining the dried powder; and(i) grinding the calcined powder.
摘要:
An apparatus for manufacturing a laminated unit of ceramic green sheets comprises an endless belt, and an applying apparatus provided at a predetermined position on the running path of the endless belt. The applying apparatus includes a reservoir for storing a ceramic slurry and a moveable blade. When the belt runs with the blade spaced a predetermined distance from the top surface of the endless belt, the ceramic slurry flows out through a gap between the blade and the belt and, thus, is applied on the belt to a predetermined thickness. The applied ceramic slurry is dried by a drier so as to form a ceramic green sheet. A conductive paste is printed on the top surface of the ceramic green sheet by a printing apparatus. The printed conductive paste is dried by a drier. The ceramic green sheet with the conductive paste printed thereon is brought again to the applying apparatus due to the movement of the endless belt, the blade of the applying apparatus is further displaced upward, and ceramic slurry is applied on the previously formed ceramic green sheet. By repeating such applied again on the ceramic green sheet. By repeating such a process, a laminated unit of the ceramic green sheets is obtained.
摘要:
An unvulcanized rubber composition, whose rubber component consists of polybutadiene rubber as an essential component and at least one of styrene-butadiene rubber and a rubber of natural rubber and/or polyisoprene rubber, has a high adhesion to a vulcanized rubber composition, whose rubber component consists mainly of at least one rubber selected from natural rubber, polyisoprene rubber, polybutadiene rubber and styrene-butadiene rubber, and can be easily adhered to the vulcanized rubber composition through vulcanization without carrying out particular surface treatment of the vulcanized rubber composition.
摘要:
A vulcanized rubber composition containing at least 30% by weight, based on the amount of the rubber component, of syndiotactic-1,2-polybutadiene has a high adhesion, and can be easily and firmly adhered to another vulcanized rubber composition or to a porous material through a syndiotactic-1,2-polybutadiene thin film by a hot-melt adhesion process.
摘要:
A method for manufacturing a powdered raw material of a basic powdered dielectric ceramic composition having compounds containing metal elements thereon. The method comprises the steps of dispersing a basic powdered dielectric ceramic composition in water to form a slurry, adding a silicon compound to the slurry to coat the powder, adding a solution containing the metal elements and a precipitating agent reactive therewith to form a precipitate, while the slurry is being stirred, and rinsing and drying the slurry.
摘要:
A nonreducible dielectric ceramic composition of a system, (A.sub.1-x R.sub.x).sub.y BO.sub.3, is prepared by preparing a slurry containing at least one compound selected from the group consisting of carbonates and hydroxides of Ba, Sr, Ca and Mg, at least one compound selected from the group consisting of carbonates and hydroxides of rare earth elements R, and at least one compound selected from the group consisting of oxides, carbonates and hydroxides of Ti, Zr and Sn; filtering the resulting slurry; washing the filter cake with water and calcining the resulting washed cake.
摘要:
To obtain a plurality of laminated ceramic capacitors, in cutting a laminated body (14) formed of a plurality of ceramic green sheets (11) formed on their surfaces with electrically conductive films (12) to serve as internal electrodes, cutting is effected in such a manner that the electrically conductive films (12) are exposed on lateral surfaces (17), which are the surfaces that are not formed with external electrodes (22, 23). Then ceramic slurry (18) is applied to the lateral surfaces (17), thereby preventing the exposure of the internal electrodes (12) on the lateral surfaces (17) where connection to the external eletrodes (22, 23) is not desired. The invention makes effective use of the entire width of the ceramic layers forming the cut laminated body (16) so as to obtain electrostatic capacity in a space-efficient manner.