| 摘要 |
PURPOSE:To obtain a sheet having a high adhesive property at the magnetic band, by extruding the 1st synthetic resin and the 2nd synthetic resin mixed with the iron oxide powder through two extruders with a common T die to laminate them and then contact bonding a synthetic resin film having a melting point higher than the 1st and 2nd synthetic resins on the surface of the 2nd synthetic resin sheet. CONSTITUTION:The 1st synthetic resin and the 2nd synthetic resin (replaceable with the same type of the 1st synthetic resin) mixed with the iron oxide powder 4a are extruded from the 1st and 2nd extruders 1 and 2 via a common T die 5. The 2nd synthetic resin 4 is laminated entirely to the 1st synthetic resin 3 or buried into the resin 3 in a belt form to obtain a sheet. For this purpose, one or more gutters 5a are provided into the die 5 and in the flow path of the extruder 2. After this, a synthetic resin film 9 having a fusing point higher than those of resins 3 and 4 is contact bonded by means of rolls 6 and 7. Thus a sheet for card is formed and then rolled up. In such a way, a sheet for magnetic card is obtained without any damage or exfoliation of the magnetic band. |
