초록 ▼

Disclosed in a packaging material having at least one layer comprising an ethylene-vinyl alcohol copolymer having a vinyl alcohol content of 40 to 80 mole % and a residual vinyl ester content lower than 4 mole %, wherein the ethylene-vinyl alcohol copolymer consists of a composition comprising a plu

Disclosed in a packaging material having at least one layer comprising an ethylene-vinyl alcohol copolymer having a vinyl alcohol content of 40 to 80 mole % and a residual vinyl ester content lower than 4 mole %, wherein the ethylene-vinyl alcohol copolymer consists of a composition comprising a plurality of copolymers differing in the vinyl alcohol content, said composition shows a plurality of endothermic peaks in a fusion curve by a differential scanning calorimeter, the composition has fusion characteristics satisfying requirements represented by the following formulae: [Figure] and Ta -Tb >10°C. wherein Sc represents an area of a triangle defined by a base line connecting the skirt of a high temperature side peak to the skirt of a low temperature side peak in two adjacent peaks in said fusion curve and lines connecting the skirts of both the peaks to the trough between both the peaks, Sa represents an area of the high temperature side peak above said triangle, Sb represents an area of the low temperature side peak above said triangle, Ta represents a peak temperature of the high temperature side peak and Tb represents a peak temperature of the low temperature side peak, and the composition has a molecular weight distribution (/) of at least 2.5. This packaging material is excellent in the gas barrier property, especially the oxygen permeation resistance under a high humidity condition, and the mechanical properties and processability.

대표청구항 ▼

A packaging material having at least one layer comprising an ethylene-vinyl alcohol copolymer having a vinyl alcohol content of 40 to 80 mole % and a residual vinyl ester content lower than 4 mole %, wherein the ethylene-vinyl alcohol copolymer consists of a composition comprising a plurality of eth

A packaging material having at least one layer comprising an ethylene-vinyl alcohol copolymer having a vinyl alcohol content of 40 to 80 mole % and a residual vinyl ester content lower than 4 mole %, wherein the ethylene-vinyl alcohol copolymer consists of a composition comprising a plurality of ethylene-vinyl alcohol copolymers differing in the vinyl alcohol content, said composition shows a plurality of endothermic peaks in a fusion curve by a differential scanning calorimeter, the composition has fusion characteristics satisfying requirements represented by the following formulae: [Figure] and 25°C. ≥Ta -Tb >10°C. wherein Sc represents an area of a triangle defined by a base line connecting the skirt of a high temperature side peak to the skirt of a low temperature side peak in two adjacent peaks in said fusion curve and lines connecting the skirts of both the peaks to the trough between both the peaks, Sa represents an area of the high temperature side peak above said triangle, Sb represents an area of the low temperature side peak above said triangle, Ta represents a peak temperature of the high temperature side peak and Tb represents a peak temperature of the low temperature side peak, and the composition has a molecular weight distribution (/) of at least 2.5.