Resin composite film including cellulose microfiber layer

A resin composite film comprising cellulose microfibers in a matrix resin, wherein the resin composite film satisfies the following conditions:

• (1) in modulus mapping obtained by atomic force microscope (AFM) measurement of a cross-section of the resin composite film in the thickness direction, the cellulose microfibers have an average fiber diameter of 0.01 μm to 2.0 μm and a maximum fiber diameter of 15 μm or smaller, as calculated from image analysis;
• (2) the resin composite film either has a glass transition temperature (Tg) of 80° C. or higher, or has none;
• (3) the storage elastic modulus of the resin composite film at 200° C. (E′200) is 0.5 GPa or greater;
• (4) the ratio (E′150/E′200) of the storage elastic modulus of the resin composite film at 150° C. (E′150) with respect to the storage elastic modulus at 200° C. (E′200) is 1 to 4.5;
• (5) the coefficient of linear thermal expansion on the X-Y plane at 200° C. (CTE200) is 100 ppm/° C. or smaller;
• and
• (6) the absolute value of the difference between the coefficient of linear thermal expansion on the X-Y plane at 150° C. (CTE150) and the coefficient of linear thermal expansion on the X-Y plane at 200° C. (CTE200) is 40 or smaller;
• wherein the matrix resin is selected from the group consisting of phenoxy resin, cresol-novolac type epoxy resin, triazine-containing phenol-novolac type epoxy resin, biphenylaralkyl type epoxy resin, bisphenol A type epoxy resin, brominated bisphenol A type epoxy resin and naphthalene type tetrafunctional epoxy resin.