Methods for manufacturing hook fastener
A hook fastener includes a stem having two lateral edges, a first surface, and a second surface. A cap extends from an upper end of the stem, and the cap includes an upper surface, a first end, a second end, and a pair of overhanging portions. The upper surface of the cap is sloped between the first end and the second end. The first and second ends are at opposite longitudinal ends of the cap, and each overhanging portion extends in a lateral direction from the stem.
1. A method of manufacturing hook fasteners, the method comprising:
forming intermediate components of a hook fastener using a die wheel;
passing the intermediate components between a first roller and a second roller; and
deforming deforming portions of the intermediate components to form caps, wherein each of the caps comprises:
an upper surface, a first end, a second end, and at least one overhanging portion,
wherein:
the upper surface of each of the caps is sloped between the first end and the second end;
the first and second ends are at opposite longitudinal ends of each of the caps; and
the at least one overhanging portion extends in a lateral direction from each of the caps,
wherein forming the intermediate components using the die wheel comprises molding the intermediate components such that longitudinal axes of the deforming portions of the intermediate components are tilted in an opposite direction to a machine direction at an angle that is approximately 10°-15° from a vertical axis,
wherein forming the intermediate components using the die wheel comprises molding the intermediate components such that each of the intermediate components comprises:
a first protruding portion extending from a base of the hook fastener; and
a second protruding portion having a width narrower than a width of the first protruding portion in the machine direction,
wherein the second protruding portions of the intermediate components are the deforming portions, and
wherein:
the first protruding portion comprises a pair of upper surfaces on both sides of the second protruding portion in the machine direction; and
one of the pair of upper surfaces of the first protruding portion at a front side in the machine direction is longer than the other of the pair of upper surfaces of the first protruding portion at a rear side in the machine direction.
2. The method of claim 1 , further comprising heating the first roller.
3. The method of claim 1 , further comprising spinning the first roller at a first speed and spinning the second roller at a second speed, wherein the first speed is 5% to 25% greater than the second speed.
4. The method of claim 1 , wherein, in a cross machine direction that is perpendicular to the machine direction, a dimension of the first protruding portion is approximately equal to a dimension of the second protruding portion.
5. The method of claim 1 , wherein forming the intermediate components comprises:
melting synthetic resin;
extruding the melted synthetic resin using the die wheel; and
cooling the extruded synthetic resin to mold the intermediate components.