Adhesive sheet and copper-clad laminate

A method for producing a two-layer copper-clad laminate comprising laminating, by using a heat roll laminating apparatus, a metal conductive foil on both sides of an adhesive sheet comprising an insulating layer having a polyimide adhesive layer on each side of the insulating layer by applying heat and pressure, wherein

• the insulating layer has a storage elasticity modulus ratio E′2/E′1 of 0.2 or less where E′1 is a storage elasticity modulus at 25° C. and E′2 is a storage elasticity modulus at 380° C.,
• the insulating layer has a coefficient of thermal expansion in the machine direction in a range of 5 to 15 ppm from 100° C. to 200° C., and
• a change in the coefficient of thermal expansion of the adhesive sheet from 100° C. to 250° C. is 2.5 ppm or less in a tension direction in which the tension is applied, and a change in the coefficient of thermal expansion of the adhesive sheet from 100° C. to 250° C. is 10 ppm or less in a direction perpendicular to the tension direction, where the change in the coefficient of thermal expansion is calculated by Equation (1):
• Change in Coefficient of Thermal Expansion=|(First Measured Value of Coefficient of Thermal Expansion)−(Second Measured Value of Coefficient of Thermal Expansion)| (1)
• where the measurements are carried out with the adhesive sheet that has been heat-treated at a temperature of 380° C. for 30 sec under tension of 20 kg/m,
• the insulating layer is a polyimide layer, and
• the polyimide layer is manufactured using a solution of polyamic acid whose raw materials include 2,2-bisaminophenoxyphenylpropane by 10 to 50 mol %, p-phenylenediamine by 30 to 60 mol %, and an oxydianiline by 10 to 30 mol % with respect to a diamine component;
• and
• wherein the adhesive sheet comprises adhesive layers on both sides of the insulating layer, and a metal conductive foil on both of the adhesive layers.