Abstract: An air filter medium includes a first porous PTFE membrane and a second porous PTFE membrane. The air filter medium has a first main surface and a second main surface, and the first porous PTFE membrane and the second porous PTFE membrane are arranged so that an air flow moving from the first main surface to the second main surface passes through the first porous PTFE membrane and subsequently through the second porous PTFE membrane. A proportion of areas occupied by the plurality of nodes on a surface of the first porous PTFE membrane is in the range of 1.5 to 3.0% and an average of the areas of the plurality of nodes is 200 ?m2 or more.

Abstract: An air filter medium includes a first porous PTFE membrane and a second porous PTFE membrane. The air filter medium has a first main surface and a second main surface, and the first porous PTFE membrane and the second porous PTFE membrane are arranged so that an air flow moving from the first main surface to the second main surface passes through the first porous PTFE membrane and subsequently through the second porous PTFE membrane. A contact angle of the first porous PTFE membrane with water is in the range of 154° to 165°.

Abstract: An air filter medium includes a first porous PTFE membrane and a second porous PTFE membrane. The air filter medium (10) has a first main surface and a second main surface, and the first porous PTFE membrane and the second porous PTFE membrane are arranged so that an air flow moving from the first main surface to the second main surface passes through the first porous PTFE membrane and subsequently through the second porous PTFE membrane. A thickness of the first porous PTFE membrane is in the range of 4 to 40 ?m and a specific surface area of the first porous PTFE membrane is 0.5 m2/g or less.

Abstract: An air filter medium includes a first porous PTFE membrane and a second porous PTFE membrane. The air filter medium has a first main surface and a second main surface, and the first porous PTFE membrane and the second porous PTFE membrane are arranged so that an air flow moving from the first main surface to the second main surface passes through the first porous PTFE membrane and subsequently through the second porous PTFE membrane. A proportion of areas occupied by the plurality of nodes on a surface of the first porous PTFE membrane is in the range of 1.5 to 3.0% and an average of the areas of the plurality of nodes is 200 ?m2 or more.

Abstract: An air filter medium includes a first porous PTFE membrane and a second porous PTFE membrane. The air filter medium has a first main surface and a second main surface, and the first porous PTFE membrane and the second porous PTFE membrane are arranged so that an air flow moving from the first main surface to the second main surface passes through the first porous PTFE membrane and subsequently through the second porous PTFE membrane. A contact angle of the first porous PTFE membrane with water is in the range of 154° to 165°.

Abstract: An air filter medium includes a first porous PTFE membrane and a second porous PTFE membrane. The air filter medium (10) has a first main surface and a second main surface, and the first porous PTFE membrane and the second porous PTFE membrane are arranged so that an air flow moving from the first main surface to the second main surface passes through the first porous PTFE membrane and subsequently through the second porous PTFE membrane. A thickness of the first porous PTFE membrane is in the range of 4 to 40 ?m and a specific surface area of the first porous PTFE membrane is 0.5 m2/g or less.

Abstract: A ventilation member (100) of the invention includes a tubular part (11), a gas permeable filter (19), and a cover part (31). In an attached state where the tubular part (11) is fit into the cover part (31), gaps functioning as gas passages (AR2 and AR3) are formed between a bottom portion (35) of the cover part (31) and the gas permeable filter (19) and between a side wall portion (39) of the cover part (31) and a body portion (17) of the tubular part (11). The opening area (S2) of a filter-end opening (15) with respect to an in-plane direction (WL) perpendicular to the thickness direction of the gas permeable filter (19) is larger than the opening area (S1) of a connection-end opening (13) with respect to the in-plane direction (WL).

Abstract: A ventilation member (100) of the invention includes a tubular part (11), a gas permeable filter (19), and a cover part (31). In an attached state where the tubular part (11) is fit into the cover part (31), gaps functioning as gas passages (AR2 and AR3) are formed between a bottom portion (35) of the cover part (31) and the gas permeable filter (19) and between a side wall portion (39) of the cover part (31) and a body portion (17) of the tubular part (11). The opening area (S2) of a filter-end opening (15) with respect to an in-plane direction (WL) perpendicular to the thickness direction of the gas permeable filter (19) is larger than the opening area (S1) of a connection-end opening (13) with respect to the in-plane direction (WL).

Abstract: A ventilation member (100) of the invention includes a tubular part (11), a gas permeable filter (19), and a cover part (31). In an attached state where the tubular part (11) is fit into the cover part (31), gaps functioning as gas passages (AR2 and AR3) are formed between a bottom portion (35) of the cover part (31) and the gas permeable filter (19) and between a side wall portion (39) of the cover part (31) and a body portion (17) of the tubular part (11). The opening area (S2) of a filter-end opening (15) with respect to an in-plane direction (WL) perpendicular to the thickness direction of the gas permeable filter (19) is larger than the opening area (S1) of a connection-end opening (13) with respect to the in-plane direction (WL).

Abstract: A ventilation member (100) of the invention includes a tubular part (11), a gas permeable filter (19), and a cover part (31). In an attached state where the tubular part (11) is fit into the cover part (31), gaps functioning as gas passages (AR2 and AR3) are formed between a bottom portion (35) of the cover part (31) and the gas permeable filter (19) and between a side wall portion (39) of the cover part (31) and a body portion (17) of the tubular part (11). The opening area (S2) of a filter-end opening (15) with respect to an in-plane direction (WL) perpendicular to the thickness direction of the gas permeable filter (19) is larger than the opening area (S1) of a connection-end opening (13) with respect to the in-plane direction (WL).

Abstract: A vent structure 100A of the present invention includes a housing 91 and a vent member 13A attached to an opening portion 91k of the housing 91. The vent member 13A is provided with a support body 11 having a through hole 11h to serve as a gas passage between the interior and the exterior of the housing 91 and a gas permeable membrane 6 fixed to the support body 11 so as to close the through hole 11h. Assuming that a thickness direction of the gas permeable membrane is a height direction, a height H1 of the support body 11 from a second opening end face 11q (aligned with an outer surface 91p of the housing 91) to a first opening end face 11p on the other side is set to 4 mm or more.

Abstract: A ventilation member (100) of the invention includes a tubular part (11), a gas permeable filter (19), and a cover part (31). In an attached state where the tubular part (11) is fit into the cover part (31), gaps functioning as gas passages (AR2 and AR3) are formed between a bottom portion (35) of the cover part (31) and the gas permeable filter (19) and between a side wall portion (39) of the cover part (31) and a body portion (17) of the tubular part (11). The opening area (S2) of a filter-end opening (15) with respect to an in-plane direction (WL) perpendicular to the thickness direction of the gas permeable filter (19) is larger than the opening area (S1) of a connection-end opening (13) with respect to the in-plane direction (WL).

Abstract: A ventilation member having: a breathable film transmitting gas passing through an opening portion of a housing in a state in which the breathable film is fixed to the opening portion; and a support including a supporting portion for supporting the breathable film and an insertion portion to be inserted into the opening portion of the housing; wherein a lock structure for locking the support in the housing by rotating the support around a central axis of the support is formed in the insertion portion.

Abstract: A ventilation member having: a breathable film transmitting gas passing through an opening portion of a housing in a state in which the breathable film is fixed to the opening portion; and a support including a supporting portion for supporting the breathable film and an insertion portion to be inserted into the opening portion of the housing; wherein the insertion portion has a lock portion in an insertion-start-side end portion thereof, the lock portion having a tapered forward end, while the insertion portion is divided into a plurality of parts circumferentially at least on an insertion start side thereof.

Abstract: A ventilation member having: a breathable film transmitting gas passing through an opening portion of a housing in a state in which the breathable film is fixed to the opening portion; and a support including a supporting portion for supporting the breathable film and an insertion portion to be inserted into the opening portion of the housing; wherein the insertion portion has a lock portion in an insertion-start-side end portion thereof, the lock portion having a tapered forward end, while the insertion portion is divided into a plurality of parts circumferentially at least on an insertion start side thereof.

Abstract: A ventilation member having: a breathable film transmitting gas passing through an opening portion of a housing in a state in which the breathable film is fixed to the opening portion; and a support including a supporting portion for supporting the breathable film and an insertion portion to be inserted into the opening portion of the housing; wherein a lock structure for locking the support in the housing by rotating the support around a central axis of the support is formed in the insertion portion.

Abstract: A porous sheet substrate that can improve a mounting work efficiency of porous sheet pieces without damaging a main body to which the porous sheet pieces are mounted. The porous sheet substrate is for cutting off porous sheet pieces, and has the structure such that cut portions and non-cut portions are formed along outlines of porous sheet pieces to be cut, and the porous sheet pieces are cut off against the non-cut portions by pushing the porous sheet pieces to be cut.