TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Compounds: The metal salt is alkali metal salt, alkaline-earth metal salt, and/or salt of d blocks of 4-th period metal.    TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The gas-barrier resin is ethylene-vinyl alcohol copolymer having an ethylene unit content of 3-70 mol% and a saponification degree of 80 mol% or more. The ethylene-vinyl alcohol copolymer has structural units (0.5-30 mol%) of formula: -CH2-CH(-C(-R1)(-R3)-R2)- and/or formula (I). The resin composition of layer (A) contains phosphoric acid compound (1-10000 ppm by phosphate conversion), carboxylic acid (1-10000 ppm), and boron compound (1-200 ppm by boron conversion). The thermoplastic resin is thermoplastic polyurethane, polyamide, and/or adhesive resin having a functional group reactive with the group of gas-barrier resin, in a molecule. The adhesive resin is a thermoplastic resin having a boron-containing group which can be converted into a boronic acid group in the presence of a carboxylic-acid-modified polyolefin and its metal salt, a boronic acid group, or water, and/or vinyl-ester type copolymer.R1-R3=H, 1-10C aliphatic hydrocarbyl, 3-10C alicyclic hydrocarbyl, 6-10C aromatic hydrocarbyl, or hydroxy;one pair in R1, R2 and R3=1-10C aliphatic hydrocarbyl, 3-10C alicyclic hydrocarbyl, or 6-10C aromatic hydrocarbyl optionally having hydroxy, carboxy or halo, with both of pair not being H;R4-R7=H, 1-10C aliphatic hydrocarbyl, 3-10C alicyclic hydrocarbyl, 6-10C aromatic hydrocarbyl, or hydroxy;andR4+R5, or R6+R7=1-10C aliphatic hydrocarbyl, 3-10C alicyclic hydrocarbyl, or 6-10C aromatic hydrocarbyl optionally having hydroxy, alkoxy, carboxy or halo, with both not being H.Preferred Properties: Layers (A,B) are laminated alternately. The average thickness of layer (A and/or B) is 0.01-10 mu m. The thickness of multilayered structure is 0.1-1000 mu m. The melt viscosity ( eta 1) of layers (A and/or B) at 210 degrees C and a shear rate of 10 second-1 is 1x 102-1x 104 Pa.second. The melt viscosity ( eta 2) at 210 degrees C and shear rate of 1000 second-1 is 1x 101-1x 103 Pa.second. The melt viscosity ratio is given by, (1/2)log10( eta 2/ eta 1) = -0.8 to -0.1. The ratio of melt viscosity of resin composition of layer (A) at 210 degrees C and a shear rate of 1000 second-1 and melt viscosity of resin composition of layer (B) is 0.3-2. The melt viscosity ( eta 1') at a shear rate of 10 second-1 of resin composition of layers (A and/or B) is 1x 102-1x 104 Pa.second at a temperature higher by 30 degrees C than the Vicat softening temperature of the resin composition of the layer. The melt viscosity ( eta 2') at a shear rate of 1000 second-1 is 1x 101-1x 103 Pa.second. The melt viscosity ratio is given by, (1/2)log10( eta 2'/ eta 1') = -0.8 to -0.1. The ratio of melt viscosity at a shear rate of 1000 second-1 of resin composition of layer (A) and melt viscosity of the resin composition of layer (B) is 0.3-3 at a temperature higher by 30 degrees C than the Vicat softening temperature of the resin composition. Joint reaction is produced in the interface of layers (A,B).