Polyamide-imide resins prepared from the reaction of aromatic diisocyanates with mixtures of polycarboxylic acids and anhydrides

Claim 2

A POLYAMIDE-IMIDE RESIN CONSISTING ESSENTIALLY OF THE REACTION PRODUCT OF (1) AN AROMATIC DIISOCYANATE IN AN AMOUNT OF 0.95 TO 1.01 MOLES, (2) AN AROMATIC DICARBOXYLIC ACID SELECTED FROM THE GROUP CONSISTING OF TEREPHTHALIC ACID, ISOPHTHALIC ACID, AND BENZOPHENONE DICARBOXYLIC ACID IN AN AMOUNT OF 0.05 T 0.40 MOLES (3) AN AROMATIC DIANHYDRIDE SELECTED FROM THE GROUP CONSISTING OF PYROMELLITIC DIANHYDRIDE, BENZOPHENONE DIANHYDRIDE, NAPHTHALENE 2, 3, 6, 7 DIANHYDRIDE, NAPHTHALENE 1, 2, 5, 6 DIANHYDRIDE, DIPHENYL 2, 3, 2'', 3''-DIANHYDRIDE, THE DIANHYDRIDE OF BIS (3'', 4''DICARBOXYPHENYL) PROPANE, THE DIANHYDRIDE OF BIS (3,4DICARBOXYPHENYL) SULFONE AND PERYLENE 3, 4, 9, ,10DIANHYDRIDE IN AN AMOUNT OF 0.01 TO 0.30 MOLES, AND (4) TRIMELLITIC ANHYDRIDE IN AN AMOUNT OF 0.5 TO 0.80 MOLES, THE TOTAL OF (2), (3) AND (4) ADDING UP TO 1 MOLE.

Claim 3

A polyamide-imide resin according to claim 1 where the diisocyanate is selected from the group consisting of 4,4''-diisocyanato-diphenyl methane and mixtures thereof with up to 0.25 moles of toluylene disocyanate, and the dianhydride is selected from the group consisting of pyromellitic dianhydride and benzophenone dianhydride and mixtures thereof.

Claim 4

An electrical conductor provided with a continuous coating of the polyamide-imide of claim 2.

Claim 5

An electrical conductor according to claim 3 wherein the coating is applied directly to the conductor.

Claim 6

An electrical conductor according to claim 3 wherein the coating is applied over a polyester base coat.

Claim 7

An electrical conductor provided with a continuous coating of the polyamide-imide of claim 1.

Claim 8

A polyamide-imide resin according to claim 1 wherein the diiosocyanate is 4,4''-diisocyanato-diphenyl methane, the dicarboxylic acid is terephthalic acid and the dianhydride is selected from the group consisting of pyromellitic dianhydride and benzophenone dianhydride.

Claim 9

A polyamide-imide resin consisting essentially of the reaction product of (1) an aromatic diisocyanate in an amount of 0.95 to 1.01 moles, (2) an aromatic dicarboxylic aCid selected from the group consisting of terephthalic acid, isophthalic acid, and benzophenone dicarboxylic acid in an amount of 0.05 to 0.40 mole, (3) an aromatic dianhydride selected from the group consisting of pyromellitic dianhydride, benzophenone dianhydride, naphthalene 2, 3, 6, 7 dianhydride, naphthalene 1, 2, 5, 6 dianhydride, diphenyl 2, 3, 2'' , 3''-dianhydride, the dianhydride of 2,2-bis (3'' , 4''-dicarboxyphenyl) propane, the dianhydride of bis (3,4-dicarboxyphenyl) sulfone and perylene 3,4,9,10-dianhydride in an amount of 0.01 to 0.30 mole, and (4) trimellitic anhydride in an amount of 0.5 to 0.80 moles, the total of (2), (3) and (4) adding up to 1 mole, in at least one solvent selected from the group consisting of N-methyl pyrrolidone, dimethyl acetamide, dimethyl formamide, dimethyl sulfoxide, N-methyl caprolactam, cresylic acid, p-cresol, m-p-cresol mixture, dimethyl sulfone, phenol, diethyl formamide and diethyl acetamide.

Claim 10

A polyamide-imide resin consisting essentially of the reaction product of (1) an aromatic diisocyanate in an amount of 0.95 to 1.01 moles, (2) an aromatic dicarboxylic aCid selected from the group consisting of terephthalic acid, isophthalic acid, and benzophenone dicarboxylic acid in an amount of 0.05 to 0.40 mole, (3) an aromatic dianhydride selected from the group consisting of pyromellitic dianhydride, benzophenone dianhydride, naphthalene 2, 3, 6, 7 dianhydride, naphthalene 1, 2, 5, 6 dianhydride, diphenyl 2, 3, 2'' , 3''-dianhydride, the dianhydride of 2,2-bis (3'' , 4''-dicarboxyphenyl) propane, the dianhydride of bis (3,4-dicarboxyphenyl) sulfone and perylene 3,4,9,10-dianhydride in an amount of 0.01 to 0.30 mole, and (4) trimellitic anhydride in an amount of 0.5 to 0.80 moles, the total of (2), (3) and (4) adding up to 1 mole, in at least one solvent selected from the group consisting of N-methyl pyrrolidone, dimethyl acetamide, dimethyl formamide, dimethyl sulfoxide, N-methyl caprolactam, cresylic acid, p-cresol, m-p-cresol mixture, dimethyl sulfone, phenol, diethyl formamide and diethyl acetamide.