The polyimide film of the present invention is produced in the following manner: polyamic acid made of a combination of a specific acid anhydride constituent and a specific diamine constituent are heated under a low-pressure circumstance for heat imidation, and the obtained imide is dissolved again in a solvent to be polyimide solution, then the polyimide solution is formed to be a film. In this manner, it is possible to provide a polyimide film essentially transparent and colorless, and has sufficient toughness to prevent occurrences of a crack or a break when the film is folded and creased by hand.

 
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> Antimony tin oxide fine particles for sunlight shielding, and disperse liquid for formation of sunlight shielding solid, sunlight shielding solid, and transparent substrate for sunlight shielding using thereof

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