| 摘要 |
PURPOSE:To prevent an incorrect alarm due to gaseous alcohol on a sensor of combustible gas such as town gas etc., by forming Co3O4-alpha-Al2O3 film on the contact surface of a gas sensor using SnO2 group with the gas to be inspected and reduces the sensitivity for gaseous alcohol. CONSTITUTION:In a detection element of combustible gas such as town gas, propane gas etc., Co3O4-alpha-Al2O3 film is formed on the surface of a gas sensor using SnO2 group and the sensitivity for alcohol vapor is reduced so as not to give an incorrect alarm by the alcohol vapor produced at the time of cooking. After the alpha-Al2O3 powder is immersed in a solution of Co(NO3)3, then taken up, dried and calcined and a paste is made by adding water to the said powder and applied on the surface of the sensor and is dried. Then, Co3O4-alpha-Al2O3 film is formed by calcining said sensor. In this manner, only gaseous alcohol is treated before reaching to the SnO2 layer and is made not to be perceived. |
