| 摘要 |
<p>PURPOSE:To obtain a bottle which is superior in buckling strength, by satisfying a specific expression in relation to a thickness of an EVOH layer of an inner layer of a pipe. CONSTITUTION:When the minimum thickness and the maximum thickness at positions between an arbitrary point tn and a point t(n+1) being separated 1,000mum in a circumferential direction from the point tn of a saponified article layer of an ethylene-vinyl acetate copolymer are made into Tn Min and Tn Max respectively, positions satisfying an expression ( I ) are existed regularly in this layer, and when the thickness of the other positions and an average thickness are made into T and T' respectively and the minimum thickness and the maximum thickness at positions between an arbitrary point tm and a point t(m+1) being separated 500mum in a circumferential direction from the point tm are made into Tm Min and Tm Max, expressions (II), (III) and (IV) are satisfied, in a biaxially oriented blow molded pipe having at least triple layer structure made of a hydrophobic and thermoplastic resin layer/a saponified article layer of ethylene-vinyl acetate copolymer whose ethylene content is more than 25-55mol% and a sponification degree of an ingredient of vinyl acetate is more then 96% and the hydrophobic and thermoplastic resin layer. As stripes are existed regularly on a bottle obtained in this manner, it is not only beautiful in appearance but also superior in mechanical properties, especially in buckling strength.</p> |
