Method for producing carboxylic acid anhydride, method for producing carboxylic imide, and method for manufacturing electrophotographic photosensitive member

1. A method for producing a carboxylic acid anhydride represented by formula (2) comprising:

a heating step performed at a temperature of 50° C. to 130° C. for heating a composition containing:

a compound represented by formula (1), the compound being a sole acid in the composition:

Y COOH) n   (1)

wherein in formulas (1) and (2), Y represents a divalent to hexavalent organic group, n represents an integer of 2 to 6, and m represents an integer of 1 to 3;

(a) an aprotic polar solvent having a boiling point of 50° C. or more selected from the group consisting of methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, pentyl acetate, methyl propionate, methyl valerate, ethyl valerate, methyl hexanoate, ethyl hexanoate, methyl heptanoate, ethyl heptanoate, N,N-dimethylformamide, N,N-diethylformamide, and N,N-dimethylacetamide, and dimethyl sulfoxide, and

(b) a solvent selected from the group consisting of toluene, cyclohexane, methylcyclohexane, ethylcyclohexane, and cycloheptane.

2. The method according to claim 1 , wherein a reaction time to produce the carboxylic acid anhydride is 0.1 to 4 hours.

3. The method according to claim 1 , wherein Y in formulas (1) and (2) are each a group represented by formula (12):

4. A method for producing a carboxylic imide, comprising:

condensing a carboxylic acid anhydride represented by formula (2) produced by the method as set forth in claim 1 and an amine.

5. A method for manufacturing an electrophotographic photosensitive member including a support member, an undercoat layer over the support member, and a photosensitive layer on the undercoat layer, the method comprising:

preparing an undercoat layer-forming coating liquid containing a carboxylic imide produced by the method as set forth in claim 4 ; and

forming the undercoat layer by applying the undercoat layer-forming coating liquid to form a coating film and drying the coating film.

6. A method for producing a carboxylic acid anhydride represented by formula (5) comprising a heating step performed at a temperature of 50° C. to 130° C. for heating a composition containing:

at least one compound selected from the group consisting of compounds represented by formula (3) and compounds represented by formula (4), the compound being a sole acid in the composition:

wherein in formulas (3) to (5), X 1 represents a residue being a tetracarboxylic acid from which four carboxy groups are removed,

(a) an aprotic polar solvent having a boiling point of 50° C. or more selected from the group consisting of methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, pentyl acetate, methyl propionate, methyl valerate, ethyl valerate, methyl hexanoate, ethyl hexanoate, methyl heptanoate, ethyl heptanoate, N,N-dimethylformamide, N,N-diethylformamide, and N,N-dimethylacetamide, and dimethyl sulfoxide, and

(b) a solvent selected from the group consisting of toluene, cyclohexane, methylcyclohexane, ethylcyclohexane, and cycloheptane.

7. The method according to claim 6 , wherein a reaction time to produce the carboxylic acid anhydride is 0.1 to 4 hours.

8. The method according to claim 6 , wherein X 1 in formulas (3) to (5) are each a group represented by formula (12):

9. A method for producing a carboxylic imide, comprising:

condensing a carboxylic acid anhydride represented by formula (5) produced by the method as set forth in claim 6 and an amine.

10. A method for manufacturing an electrophotographic photosensitive member including a support member, an undercoat layer over the support member, and a photosensitive layer on the undercoat layer, the method comprising:

preparing an undercoat layer-forming coating liquid containing a carboxylic imide produced by the method as set forth in claim 9 ; and

forming the undercoat layer by applying the undercoat layer-forming coating liquid to form a coating film and drying the coating film.