Resin composition and use thereof

1. A resin composition solution obtained by dissolving, in an organic solvent, a thermosetting resin composition containing at least:

a (A) urethane imide oligomer having a terminal carboxylic acid group; and

a (B) thermosetting resin

wherein:

the (A) urethane imide oligomer having a terminal carboxylic acid group is obtained by:

(i) reacting at least a (a) diol compound and a (b) diisocyanate compound so as to synthesize a terminal isocyanate compound;

(ii) reacting the terminal isocyanate compound with a (c) tetracarboxylic acid dianhydride so as to synthesize a urethane imide oligomer having a terminal acid anhydride; and

(iii) reacting the urethane imide oligomer having a terminal acid anhydride with (d) water,

the (a) diol compound being represented by General Formula (1):

HO R 1 OH   (1)

wherein R represents a divalent organic group; and 1 represents an integer of 1 to 20,

O═C═N—X—N═C═O   (2)

the (b) diisocyanate compound being represented by General Formula (2):

wherein X represents a divalent organic group, and

the (c) tetracarboxylic acid dianhydride being represented by General Formula (3):

wherein Y represents a tetravalent organic group;

wherein the (A) urethane imide oligomer having a terminal carboxylic acid group is a tetracarboxylic acid urethane imide oligomer,

wherein the (a) diol compound contains at least a polycarbonate diol represented by General Formula (4):

wherein each R 1 independently represents a divalent organic group; and m represents an integer of 1 to 20,

wherein the resin composition solution having a solute concentration of 60% by weight or more and 90% by weight or less, and

wherein the resin composition solution has a viscosity of not less than 180 poise and not more than 250 poise at 23° C.

2. The resin composition solution as set forth in claim 1 , wherein the (B) thermosetting resin is contained in the resin composition solution by 1 to 100 parts by weight, relative to 100 parts by weight of the (A) urethane imide oligomer having a terminal carboxylic acid group.

3. A photosensitive resin composition containing at least:

a resin composition solution as set forth in claim 1 ;

a (C) photosensitive resin; and

a (D) photopolymerization initiator.

4. The photosensitive resin composition as set forth in claim 3 , wherein:

the (A) urethane imide oligomer having a terminal carboxylic acid group, the (B) thermosetting resin, the (C) photosensitive resin, and the (D) photopolymerization initiator are contained in the photosensitive resin composition in such an amount ratio that the (C) photosensitive resin and the (D) photopolymerization initiator are contained therein respectively by 10 to 200 parts by weight and by 0.1 to 50 parts by weight, relative to 100 parts by weight of a total solid content of the (A) urethane imide oligomer having a terminal carboxylic acid group and the (B) thermosetting resin.

5. A resin film obtained by applying, to a surface of a base material, a resin composition solution as set forth in claim 3 and then drying the resin composition solution thus applied.

6. An insulating film obtained by curing a resin film as set forth in claim 5 .

7. A printed wiring board provided with an insulating film, wherein:

the insulating film is an insulating film as set forth in claim 6 ; and

the printed wiring board is covered with the insulating film.

8. A resin composition solution obtained by dissolving, in an organic solvent, a photosensitive resin composition as set forth in claim 3 .

9. A resin film obtained by applying, to a surface of a base material, a resin composition solution as set forth in claim 8 and then drying the resin composition solution thus applied.

10. An insulating film obtained by curing a resin film as set forth in claim 9 .

11. A printed wiring board provided with an insulating film, wherein:

the insulating film is an insulating film as set forth in claim 10 ; and

the printed wiring board is covered with the insulating film.

12. The resin composition solution as set forth in claim 1 , wherein the (A) urethane imide oligomer having a terminal carboxylic acid group further has a carboxyl group in its side chain.