INSULATING FILM-COATED METAL FOIL

摘要

An insulating film-coated metal foil having on one or both surfaces thereof an organic-inorganic hybrid layer containing dimethylsiloxane and a metalloxane comprising a metal other than Si. Relative to the concentration [Si]1/4t of the Si at a depth of ¼t from the surface of the organic-inorganic hybrid layer in the thickness direction of the hybrid layer, the concentration [Si]3/4t of the Si at a depth of ¾t from the surface of the organic-inorganic hybrid layer in the thickness direction of the hybrid layer satisfies [Si]1/4t<[Si]3/4t, and ([Si]3/4t−[Si]1/4t)/[Si]3/4t is 0.02-0.23. Provided is a metal foil that can be used in solar cell substrates, flexible circuit substrates, etc., that exhibits surface flatness, pliability, insulating properties and thermal resistance properties, and that has a layer having a surface which is not susceptible to scratching by processes in which substrates are handled, such as conveyance and transshipment.

主权项

1. A process for producing an insulating film-coated metal foil having an organic-inorganic hybrid layer, comprising:
coating a metal foil with a liquid which has been obtained by blending a polydimethylsiloxane and a metal alkoxide containing one or more metals selected from: Mg, Ca, Y, Al, Sn, Ti, Zr, Nb, Ta and W, drying the coating at 70 to 210° C., and subjecting the coating to temperature elevation at a temperature rise rate of 30 to 80° C./min and holding the temperature at 250 to 600° C. for 30 to 240 minutes, wherein the concentration [Si]1/4t of Si at a depth of ¼t from the surface of the organic-inorganic hybrid layer along the thickness direction of the layer has the following relationship with the concentration [Si]3/4t of Si at a depth of ¾t from the surface of the organic-inorganic hybrid layer along the thickness direction of the layer:
[Si]1/4t<[Si]3/4t and the value of the relative ratio of the Si concentrations, RSi=[Si]3/4t−[Si]1/4t/[Si]3/4t, is from 0.02 to 0.23.