Patent ID: 7141614

Claim:
A photosensitive resin composition containing a (A) soluble polyimide and a (B) (meth)acrylic compound, the (A) soluble polyimide (i) being soluble in an organic solvent and (ii) having a structural unit represented by Formula (1): where R 1 is a tetravalent organic group, and R 2 is a divalent organic group having a siloxane structure or an aromatic ring structure, and the (B) (meth)acrylic compound containing, as the (A) soluble polyimide having the structural unit represented by Formula (1), a polyimide having a structural unit represented by Formula (3); where R 11 is a tetravalent organic group containing an aromatic ring structure or an alicyclic structure, R 21 is at least one of a divalent organic group represented by Formula (4) and a divalent organic group represented by Formula (5): where each R 22 is independently a divalent hydrocarbon group or a divalent phenyl group, each R 23 is independently an alkyl group having 1 to 3 carbon atoms, or a phenyl group, and a is an integer of 3 to 30, and where each R 24 is independently a hydroxyl group or a carboxyl group, R 25 is a direct bond or a divalent organic group selected from the group (6): where each R 26 is independently a hydrogen atom, a methyl group, or a methyl halide in which 1 to 3 hydrogen atoms are substituted, b is an integer in a range of 0 to 3, and c is an integer of 1 or 2, containing, as the (A) soluble polyimide having the structural unit represented by Formula (3), a first polyimide, a second polyimide and a third polyimide, the first polyimide having a recurring unit having a structure represented by Formula (7): where R 11 is identical with R 11 in Formula (3), R 22 and R 23 are identical with R 22 and R 23 in Formula (4), and a is an integer of 3 to 30, the second polyimide having a recurring unit having a structure represented by Formula (8): where R 11 is identical with R 11 in Formula (3), R 24 and R 25 are respectively identical with R 24 and R 25 in Formula (5), b is an integer of 0 to 3, and c is an integer of 1 or 2, the third polyimide having a structure in which R 21 in Formula (3) excludes a siloxane structure represented by Formula (4), and an aromatic ring structure represented by Formula (5), wherein a first polyimide content is in a range of 5 mol % to 80 mol %, a second polyimide content is in a range of 0.5 mol % to 80 mol %, and third polyimide content is the rest, based on 100 mol % of the (A) soluble polyimide; and wherein a log-mean viscosity (0.5 g/100 ml) of the photosensitive resin composition is 0.16 or more.