Molded surface fastener
The molded surface fastener has a base portion, right and left resin-intrusion-preventing wall portions standing on the base portion, and a plurality of engaging elements disposed between the right and left resin-intrusion-preventing wall portions. The resin-intrusion-preventing wall portions contain magnetic particles, and at least a part of a region formed of the resin-intrusion-preventing wall portions and the base portion has a concentration gradient portion in which a concentration of the contained magnetic particles is decreased toward at least one direction. This makes it possible to enhance the adhesion property between the part containing the magnetic particles and the part substantially containing no magnetic particles, and to suppress occurrence of cracks or the like between the containing part and the non-containing part of the magnetic particles at the time of manufacturing the molded surface fastener and at other times.
1. A synthetic resin molded surface fastener, to be integrated to a surface of a cushion body at a time of foam molding of the cushion body, the molded surface fastener comprising a flat plate-shaped base portion provided with an upper surface and a lower surface, right and left resin-intrusion-preventing wall portions standing on the upper surface of the base portion along a length direction, and a plurality of hook shaped engaging elements disposed between the right and left resin-intrusion-preventing wall portions and containing magnetic particles in the right and left resin-intrusion-preventing wall portions, wherein,
at least a part of a region formed of the resin-intrusion-preventing wall portions and the base portion has a concentration gradient portion in which a concentration of the magnetic particles decreases toward at least one direction.
2. The molded surface fastener according to claim 1 , wherein the concentration gradient portion has a downward gradient portion in which the concentration of the magnetic particles decreases as it extends downward.
3. The molded surface fastener according to claim 2 , wherein the downward gradient portion is disposed across a region of 1/10 or more of a height dimension of the resin-intrusion-preventing wall portions from the base portion.
4. The molded surface fastener according to claim 1 , wherein the concentration gradient portion has a high concentration portion in which the concentration of the magnetic particles is highest on an upper end part including an upper surface of the right and left resin-intrusion-preventing wall portions.
5. The molded surface fastener according claim 1 , wherein the concentration gradient portion has an inward gradient portion in which the concentration of the magnetic particles decreases from an outside apart from the engaging elements toward an inside close to the engaging elements along a right and left direction.
6. The molded surface fastener according to claim 1 , wherein the concentration gradient portion has an outward gradient portion in which the concentration of the magnetic particles decreases from an inside close to the engaging elements toward an outside apart from the engaging elements along a right and left direction.
7. The molded surface fastener according to claim 1 , wherein the right and left resin-intrusion-preventing wall portions have at least one vertical wall row formed along the length direction respectively, and
the vertical wall row has a plurality of divided vertical wall portions disposed along the length direction at a predetermined pitch intermittently and provided with a certain height dimension.
8. The molded surface fastener according to claim 7 , wherein the concentration gradient portion of the divided vertical wall portions have a length direction gradient portion in which the concentration of the magnetic particles decreases along a front and rear direction.
9. The molded surface fastener according to claim 7 , wherein the resin-intrusion-preventing wall portions have a plurality of the vertical wall rows formed of the divided vertical wall portions,
the divided vertical wall portions are arranged in a staggered manner in a plurality of the vertical wall rows,
the divided vertical wall portions in each of the vertical wall rows is connected to an adjacent two of the divided vertical wall portions in the other vertical wall row via connecting wall portions, and
the divided vertical wall portions and the connecting wall portions are continuously disposed in a series with a certain height dimension.
10. The molded surface fastener according to claim 9 , wherein the vertical wall rows of the resin-intrusion-preventing wall portions have a first vertical wall row disposed on an inner side in a right and left direction and a second vertical wall row disposed on an outer side in the right and left direction,
the divided vertical wall portions in the first vertical wall row and the divided vertical wall portions in the second vertical wall row are disposed to be partially overlapped with each other in a side view from the right and left direction, and
the connecting wall portions are disposed along a width direction.
11. The molded surface fastener according to claim 9 , wherein a connecting length of the connecting wall portion for connecting between the divided vertical wall portions is set to be larger than a dimension of the divided vertical wall portions in a right and left direction.