Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
287 words
A process for preparing an imide prepolymer, which comprises the steps of: (1) heating, at 70° to 170° C. for 5 to 120 minutes, at least one bis-imide (A) represented by the formula (a): ##STR6## wherein R 1 stands for a divalent organic radical having a carbon-carbon double bond, and R 2 stands for a divalent organic radical having at least 2 carbon atoms, and at least one diamine (B) represented by the formula (b): H.sub.2 N--R.sub.3 --NH.sub.2 (b) wherein R 3 stands for a divalent organic radical having at least 2 carbon atoms, in an organic solvent having a boiling point of 70° to 170° C. as measured under a pressure of 760 mmHg, said at least one bis-imide (A) and said at least one diamine (B) being employed at a molar ratio of the component (A) to the component (B) of from 1:0.1 to 1:1, to obtain a reaction mixture containing an intermediate reaction product which is insoluble or slightly soluble in a low boiling point organic solvent, said solvent having a boiling point no higher than about that of methyl ethyl ketone; and (2) further heating, at 50° to 140° C. for 5 to 120 minutes, the reaction mixture together with at least one 1,2-epoxy compound (C) having at least two 1,2-epoxy groups, said at least one 1,2-epoxy compound (C) being employed in a weight proportion, relative to the total of said at least one bis-imide (A), said at least one diamine (B) and said at least one 1,2-epoxy compound (C), of from 10 to 80%, to obtain a reaction mixture containing an imide prepolymer having an increased solubility relative to that of said intermediate reaction product in said low boiling point organic solvent.
Claim 2
Dependent Claim
287 words
A process for preparing an imide prepolymer, which comprises the steps of: (1) heating, at 70° to 170° C. for 5 to 120 minutes, at least one bis-imide (A) represented by the formula (a): ##STR6## wherein R 1 stands for a divalent organic radical having a carbon-carbon double bond, and R 2 stands for a divalent organic radical having at least 2 carbon atoms, and at least one diamine (B) represented by the formula (b): H.sub.2 N--R.sub.3 --NH.sub.2 (b) wherein R 3 stands for a divalent organic radical having at least 2 carbon atoms, in an organic solvent having a boiling point of 70° to 170° C. as measured under a pressure of 760 mmHg, said at least one bis-imide (A) and said at least one diamine (B) being employed at a molar ratio of the component (A) to the component (B) of from 1:0.1 to 1:1, to obtain a reaction mixture containing an intermediate reaction product which is insoluble or slightly soluble in a low boiling point organic solvent, said solvent having a boiling point no higher than about that of methyl ethyl ketone; and (2) further heating, at 50° to 140° C. for 5 to 120 minutes, the reaction mixture together with at least one 1,2-epoxy compound (C) having at least two 1,2-epoxy groups, said at least one 1,2-epoxy compound (C) being employed in a weight proportion, relative to the total of said at least one bis-imide (A), said at least one diamine (B) and said at least one 1,2-epoxy compound (C), of from 10 to 80%, to obtain a reaction mixture containing an imide prepolymer having an increased solubility relative to that of said intermediate reaction product in said low boiling point organic solvent.
Claim 3
Dependent Claim
28 words
A process according to claim 1, wherein said solvent having a boiling point of 70° to 170° C. is 2-methoxyethanol, 2-ethoxyethanol, 2-(methoxymethoxy)ethanol, 2-isopropoxyethanol or a mixed solvent thereof.
Claim 4
Dependent Claim
11 words
An imide prepolymer produced by a process according to claim 1.