| 摘要 |
<p>PURPOSE:To bury an adhesive for a coverlay film without gap in an FPC circuit and to prevent a film from occurrence of such inferiority as elongation, cracks, wrinkles and detects by laminating integrally a vinyl chloride sheet and a kraft paper directly or through an adhesive layer and using it as a cushioning material. CONSTITUTION:A kraft paper 1a or a vinyl chloride sheet 1c has no stiffness, it is difficult to handle each single one but by bonding the kraft paper 1a and the vinyl chloride sheet 1c in advance through an adhesive layer 1b and using it integrally, not only handling properties but workability are improved but also the karft paper suppresses elongation and shrinkage of the vinyl chloride sheet 1c in the transverse direction when hot contact bonding is performed and as the result, it is possible to prevent the film from occurrence of dimensional inferiority, wrinkles and cracks. As the adhesive layer 1b bonding the kraft paper 1a and the vinyl chloride sheet 1c together, such an adhesive as an epoxy, a urethane and an acrylic adhesive can be used and the thickness of the adhesive layer 1b is pref. 3-15mum.</p> |
