Abstract: A method for producing a filter element has three steps. In first step, a filter body including at least one first passageway and at least one second passageway or clearance extends closely and substantially parallel to the first passageway and communicate with first hole through a filter material is formed. In second step, a sheet-shaped thermoplastic adhesive is arranged on one end of the filter body, the first passageway and the second passageway or clearance are open at the one end of the filter body. In third step, the sheet-shaped thermoplastic adhesive is melted by heating to close and seal an end of the second passageway or clearance at the one end of the filter body so that the passageways do not deform.

Abstract: A filter element which is improved in filter performance and suitable for use in various types of filters, and a manufacturing method thereof. In the filter element, a multiplicity of tubes each formed of a filtering material and having a substantially circular shape in cross-section are arranged side by side into a tubular assembly with the axes of the tubes lying parallel to one another; inter-tube openings are closed at one end of the tubular assembly which end serves as the inlet side for a fluid to be filtered, whereas intra-tube openings are closed on the opposite end of the tubular assembly; and the total cross-sectional area of all the inter-tube openings is set smaller than the total cross-sectional area of all the intra-tube openings, but larger than the minimum cross-sectional area of a path through which the fluid is supplied to the tubular assembly.

Abstract: A filter element which is improved in filter performance and suitable for use in various types of filters. In the filter element, a multiplicity of tubes each formed of a filtering material and having a substantially circular shape in cross-section are arranged side by side into a tubular assembly with the axes of the tubes lying parallel to one another; inter-tube openings are closed at one end of the tubular assembly which end serves as the inlet side for a fluid to be filtered, whereas intra-tube openings are closed on the opposite end of the tubular assembly; and the total cross-sectional area of all the inter-tube openings, is set smaller than the total cross-sectional area of all the intra-tube openings, but larger than the minimum cross-sectional area of a path through which the fluid is supplied to the tubular assembly.