| 摘要 |
PURPOSE:To prepare a small-sized detecting element capable of detecting a wide range of the concentration of alcohol with excellent precision by forming a metal-oxide ceramic film of Cr2O3 or the like between electrodes in a pair arranged opposedly on an insulating substrate. CONSTITUTION:Twenty grams of powder selected from 100wt% of Cr2O3, or 60wt% of Cr2O3 and 40wt% of WO3, or 70wt% of Cr2O3 and 30wt% of ZrO2, and twenty grams of organic vehicle are fully stirred to form paste. This paste is printed on an alumina insulating substrate 1 having platinum electrodes 2 and 3 which are opposed comblike by the screen printing method. After being dried for one hour in an oven heated to 100 deg.C, the printed paste film is baked in a baking furnace with an oxidizing ambience under the conditions of the temperature rising velocity of 100 deg.C per hour, baking temperature of 1,300 deg.C and the baking time of two hours, and thereby an alcohol concentration detecting film 20mum thick is formed. The detecting element thus formed is fitted for detecting the concentration of polarized solution, such as alcohol in nonpolarized solution, including gasoline. |
