| 摘要 |
<p>A process of producing a multiple-layer filter medium comprising a porous support and a filtering layer formed on one of opposite surfaces of the porous support. The process includes the steps of: immersing the porous support in a liquid, to fill pores in the porous support with the liquid and thereby remove a gas from the pores; preparing a suspension containing particles to form the filtering layer; disposing the porous support such that the above-indicated one surface is exposed to a flow of the suspension, and partially defines a conduit through which the suspension flows; holding the other surface of the porous support under a first pressure lower than a second pressure acting on the above-indicated one surface, and effecting the flow of the suspension in contact with the above one surface for a predetermined time, to permit the particles in the flow to be deposited on the above one surface, thereby forming the filtering layer; draining the conduit of the suspension, and introducing into the conduit a gas having a third pressure higher than the first pressure, and to thereby remove aqueous components from the porous support and the filtering layer; and firing the porous support and the filtering layer.</p> |
