NOVELTY - A polyimide precursor varnish comprises polyimide precursor and composition containing solvent. The polyimide precursor is diamine obtained by polycondensing acid dianhydride. The diamine contains 27-87 mol% 4-((4-aminophenyl)methyl)aniline (A) (I) and 13-73 mol% 4-(4-aminophenoxy)aniline (B) (II). Sum total of component (A) and component (B) is 80 mol% or more. The acid dianhydride is 5,11-dioxatricyclo(7.3.0.03,7)dodeca-1,3(7),8-triene-4,6,10,12-tetrone (III).    USE - Polyimide precursor varnish is used for polyimide resin for forming insulated wire, and heat-resistant film for forming adhesive tape and laminated board (all claimed). Uses include but are not limited to printed wiring board, motor vehicle, aerospace components, electronic office equipment, heat radiating component, electromagnetic wave shield component, solar cell component, semiconductor sealing material, semiconductor protective film, radiation-proof component, etc.    ADVANTAGE - The polyimide precursor varnish has excellent xylene tolerance, and provides polyimide resin capable of forming insulating wire with excellent insulating property, heat resistance, and flexibility and low elastic characteristics.    DETAILED DESCRIPTION - A polyimide precursor varnish comprises polyimide precursor and composition containing solvent. The polyimide precursor is diamine obtained by polycondensing acid dianhydride. The diamine contains 27-87 mol% 4-((4-aminophenyl)methyl)aniline (A) of formula (I) and 13-73 mol% 4-(4-aminophenoxy)aniline (B) of formula (II). Sum total of component (A) and component (B) is 80 mol% or more. The acid dianhydride is 5,11-dioxatricyclo(7.3.0.03,7)dodeca-1,3(7),8-triene-4,6,10,12-tetrone of formula (III). The content of diamine is 47.5-52.5 mol%. The content of acid dianhydride with respect to sum total of diamine and acid dianhydride is 52.5-47.5 mol%. INDEPENDENT CLAIMS are included for the following:    (1) polyimide resin, which is formed by imidating molding obtained from the polyimide precursor varnish;    (2) insulated wire (1), which consists of conductor (10), and insulation coating layer (20) which covers the conductor. The insulated coating layer contains the polyimide resin;    (3) heat-resistant film, which is provided with film formed by imidating the coating film obtained from the polyimide precursor varnish;    (4) adhesive tape, which consists of the heat-resistant film, and adhesive layer, which is laminated on or both surfaces of the heat-resistant film; and    (5) laminated board, which consists of metal foil laminated on heat-resistant film containing epoxy or thermoplastic polyimide through contact bonding layer.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic sectional view of the insulated wire.    Insulated wire (1)    Conductor (10)    Insulation coating layer (20)