Abstract: A method for producing a thermoplastic resin string roll of the present invention uses a core made of a plurality of core pieces that are arranged along a circumference and can move back and forth in a diameter direction, the outer faces of the core pieces forming a part of a cylinder when the core pieces are extended in the diameter direction. The end of a thermoplastic resin string is fixed, while the core pieces of the core are extended in the diameter direction. Then, the core is rotated to wind the thermoplastic resin string a plurality of times around the periphery of the core. Thereafter, supersonic vibration is applied to a plurality of layers of the thermoplastic resin string that is wound round the core via a horn, thereby causing frictional heat, so that the plurality of layers of the thermoplastic resin string are connected by thermal fusion due to the frictional heat, and then the thermoplastic resin string is wound to produce a roll.

Abstract: A method for manufacturing a thermoplastic synthetic resin band 1 according to the present invention includes passing a thermoplastic synthetic resin base material 10 between a pair of embossing rolls 2, on whose outer surface parallel concave grooves 2a of a constant width, which cross each other obliquely, and a plurality of rhombus-shaped convex portions 2b, which are partitioned with a constant surface area by the parallel concave grooves 2a, are formed, and forming, on a front and a back side of the thermoplastic synthetic resin base material 10, a plurality of parallel convex stripes 1a of a constant width, which cross each other obliquely, and a plurality of rhombus-shaped concave grooves 1b, partitioned with a constant surface area by the parallel convex stripes 1a.

Abstract: The present invention relates to: a packaging strap coil and its production method, wherein the innermost strap end is securely fixed to prevent un-winding thereof and the strap can be smoothly drawn out to the innermost end for strap-packaging of an item; a packaging strap coil unit which prevents deformation of the strap coil; and a packaging machine. The strap coil 11 comprises a number of layers of a resin packaging strap 11a wound helically and carelessly around a hollow 11b defining the axis of the strap coil 11. The strap 11a is made of a thermoplastic resin at least on its external surface. In the strap coil 11, a plurality of perforations 11d are pierced in the vicinity of an innermost end of the strap 11a through to a plurality of laminated layers. Each perforation 11d provides a melt-bonded area 11e along its periphery to bond the laminated layers of the strap 11a together.