Patent ID: 8419308
Filing Date: 2013-04-16
Classification: B42F,Y10T

Abstract:
1. A document fastener comprising: a plate material made of resin having a body extending in a longitudinal direction and a pair of foldable pieces located at end portions of the body, wherein said plate material is obtained by rolling a polyorefin resin sheet and then drawing the polyorefin resin sheet, said plate material having a width in a transverse direction to the longitudinal direction, wherein tip portions of the foldable pieces are each formed by rolling so as to have a thickness that is less than a thickness of other portions of the foldable pieces, and so as to have a hardness which is greater than that of other portions of the foldable pieces, wherein at least a portion of each foldable piece is curved so as to have a concave shape in cross-section, wherein a boundary between the body part and each foldable piece is made to be foldable, wherein said plate material has a property of maintaining a folded state at a time when the plate material is folded in a direction of its thickness, wherein a folded state on each boundary can be held by making use of the properties of the resin itself without engaging either foldable piece with the body part and without engaging each of the foldable pieces with each other, wherein a length of said plate material in the longitudinal direction is greater than the width in the transverse direction, and wherein the width in the transverse direction is greater than the thickness of the plate material.