To provide transparency and resistance to impact by melt kneading ion crosslinking aromatic vinyl resin in an extruder, carrying out the vertical orientation between rolls and then apllying the tentering method lateral orientation by clip grasping.
Ion crosslinking aromatic vinyl resin is melt kneaded in an extruder, and the vertical orientation between rolls is carried out as a first process, and the tentering method lateral orientation by clip grasping is applied as a second process. The ion crosslinking aromatic vinyl resin is used for a crosslinking structure by forming metallic atoms and salt by carboxyl in a copolymer composed of, for instance, an aromatic cyclic vinyl compound and (meth)acrylic acid. Styrene is preferred as an aromatic vinyl compound. For the melt viscosity forming indication representing the molecular weight of the ion crosslinking aromatic vinyl resin, the 5wt.% toluen solution viscosity is preferably in the range of 10.1-122cSt in the ion crosslinking state.
AOCHI ISAO
ARAI KOSUKE
