NOVELTY - A polyamic acid varnish composition contains polyamic acid obtained by addition polymerizing ester group containing tetracarboxylic acid dianhydride and aromatic diamine, and solvent. The difference of heat of fusion peak temperatures (b, a) is 5 degrees C or less, obtained by differential scanning calorimetry. The temperature (b) is the intersection of the virtual tangent which uses as a contact temperature which starts up to the heat of fusion peak starts, and the straight line which follows a linear portion of the heat of fusion peak. The temperature (a) is 247 degrees C or more.    USE - Polyamic acid varnish composition for forming polyimide resin and metal polyimide composite (both claimed). Uses include but are not limited to substrate for electroluminescent display board, liquid crystal display, electronic paper, solar cells, flexible printed circuit board and tape automated bonding, protective film of semiconductor and interlayer insulation film of integrated circuit.    ADVANTAGE - The polyamic acid varnish composition is a high molecular weight component without a gel component, and provides metal composite having high mechanical strength and low hygroscopic expansion coefficient.    DETAILED DESCRIPTION - A polyamic acid varnish composition contains polyamic acid obtained by addition polymerizing 4-(((1,3-dioxo-1,3-dihydro-2-benzofuran-5-yl)carbonyl)oxy)-2-methylphenyl 1,3-dioxo-1,3-dihydro-2-benzofuran-5-carboxylate and aromatic diamine, and solvent. The difference of heat of fusion peak temperatures (b, a) is 5 degrees C or less, obtained by differential scanning calorimetry. The temperature (b) is the intersection of the virtual tangent which uses as a contact temperature which starts up to the heat of fusion peak starts and the straight line which follows a linear portion of the heat of fusion peak. The temperature (a) is 247 degrees C or more. INDEPENDENT CLAIMS are included for the following:    (1) manufacture of the polyamic acid varnish composition, which involves carrying out anhydrous storing process and producing ester group containing tetracarboxylic acid dianhydride after recrystallization in organic solvent having cyclic ester structure, cyclic ketone structure, cyclic carbonate structure and cyclic and cyclic sulfone structure, and addition polymerizing the tetracarboxylic acid dianhydride and aromatic diamine in a solvent. The solid concentration in the organic solvent is 50% or less. The complete dissolution of the tetracarboxylic acid dianhydride is carried out at 150-300 degrees C; and    (2) metal-polyimide composite, which is obtained by forming a layer containing polyimide resin on a metal substrate.