NOVELTY - A multilayered structure has a surface-treatment layer formed by contacting a flame formed by burning mixed gas on a base-material layer. The ratio of peak area (S0) of light absorption peak of surface-treatment layer observed at 989-1327 cm-1 when the infrared-absorption-spectrum measurement of multilayer structure is carried out with respect to peak area (S) of light absorption peak of surface-treatment layer observed at 989-1327 cm-1 when the infrared-absorption-spectrum measurement of to-be-processed multilayer structure is carried out, is more than 0.6 to less than 1.    USE - Multilayered structure. Uses include but are not limited to liquid crystal display, organic electroluminescent element, flexible display, solar cell, dye-sensitized solar cell, vacuum heat insulating material panel, packaging material, medical device and electronic device.    ADVANTAGE - The multilayered structure has excellent adhesiveness with respect to other base material, print quality and coating characteristics, and is economical.    DETAILED DESCRIPTION - A multilayered structure has a surface-treatment layer formed by contacting a flame formed by burning mixed gas containing silicon alkoxide and/or alkyl silicon compound and combustible gas on a base-material layer. The ratio of peak area (S0) of light absorption peak of surface-treatment layer observed at 989-1327 cm-1 when the infrared-absorption-spectrum measurement of multilayer structure is carried out with respect to peak area (S) of light absorption peak of surface-treatment layer observed at 989-1327 cm-1 when the infrared-absorption-spectrum measurement of to-be-processed multilayer structure is carried out, is more than 0.6 to less than 1. The to-be-processed multilayer structure is obtained by washing the multilayered structure with acetone. The thickness of surface-treatment layer of to-be-processed multilayered structure washed with acetone is more than 0.01 to less than 1. INDEPENDENT CLAIMS are included for the following:    (1) manufacture of multilayered structure, which involves contacting the flame on the base-material layer at flame-treatment rate of 1-200 m/minute for 0.1-100 seconds and forming surface-treatment layer; and    (2) evaluation of surface-treatment layer in the multilayered structure, which involves calculating the peak area (S0) and peak area (S), such that adhesiveness, print quality or coating characteristics of surface-treatment layer is evaluated.