Multi-layer polyimide films and flexible circuit substrates therefrom
AssigneeDu Pont-Toray Co., Ltd.
InventorKenji Uhara
Life of this patent
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Abstract
A multi-layer polyimide film including two or more laminated polyimide film layers is provided, with at least one of the two or more polyimide film layers is obtained by imidizing a polyamic acid derived from the reaction of at least one aromatic diamine containing 1-100 mol percent of carboxy-4,4′-diaminobiphenyl represented by the following formula, wherein m and n represent integers of 4 or less, including 0, and (m+n) is an integer of 1 or greater, and at least one aromatic tetracarboxylic dianhydride or a derivative thereof. Methods for obtaining a multi-layer polyimide film laminate can exhibit a peel strength of 10N/cm when laminated to a metal foil using an adhesive and can have a water absorption value of less than 3.0 weight percent.
Claims20
A multi-layer polyimide film, comprising:
- two or more polyimide film layers, with at least one of the two or more polyimide film layers obtained by imidizing a polyamic acid obtained from the reaction of at least one aromatic diamine containing 1-100 mol percent of carboxy-4,4′-diaminobiphenyl of Formula 1:
- wherein m and n represent integers of 4 or less, including 0, and (m+n) is an integer of 1 or greater, and at least one aromatic tetracarboxylic dianhydride or a derivative thereof.
A method for obtaining a multi-layer polyimide film laminate, comprising the steps of:
- providing a polyimide film;
- coating onto at least one side of the polyimide film a polyamic acid obtained from the reaction of at least one aromatic diamine containing 1-100 mol percent of carboxy-4,4′-diaminobiphenyl of Formula 1
- wherein m and n represent integers of 4 or less, including 0, and (m+n) is an integer of 1 or greater, and at least one aromatic tetracarboxylic dianhydride or a derivative thereof;
- and, imidizing the polyamic acid to form a coated polyimide film wherein the coated polyimide film and the polyimide film form a multi-layer polyimide film laminate.
A method for obtaining a multi-layer polyimide film laminate, comprising the steps of:
- providing a polyamic acid film;
- coating onto at least one side of the polyamic acid film a polyamic acid solution comprising at least one aromatic diamine containing 1-100 mol percent of carboxy-4,4′-diaminobiphenyl of Formula 1
- wherein m and n represent integers of 4 or less, including 0, and (m+n) is an integer of 1 or greater, and at least one aromatic tetracarboxylic dianhydride or a derivative thereof;
- and imidizing the polyamic acid solution and polyamic acid film to form a multi-layer polyimide film laminate.
Dependencies are inferred from the claim text.