| CPC C08G 73/1067 (2013.01) [B32B 15/08 (2013.01); B32B 27/281 (2013.01); B32B 2250/40 (2013.01); B32B 2307/308 (2013.01)] | 4 Claims |
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1. A polyimide film comprising:
a first imide bond unit having a glass transition temperature of 400° C. or higher; and
a second imide bond unit having a glass transition temperature of less than 400° C.,
wherein the first imide bond unit is derived from coupling between a first dianhydride monomer and a diamine monomer and the second imide bond unit is derived from coupling between a second dianhydride monomer and a diamine monomer,
wherein the first dianhydride monomer of the first imide bond unit comprises pyromellitic dianhydride (PMDA),
wherein the diamine monomer of the first imide bond unit comprises 4,4′-oxydianiline (ODA),
wherein the first imide bond unit is present in an amount of about 39 mol % to about 90 mol % in the polyimide film;
wherein the polyimide film has a glass transition temperature of 374° C. or higher and 415° C. or lower,
wherein the polyimide film has a coefficient of thermal expansion of 3.0 ppm/° C. or more and 5.7 ppm/° C. or less, as calculated averaging coefficients of thermal expansion in a machine direction (MD) and in a transverse direction (TD).
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