Method for forming resist pattern, method for manufacturing printed wiring board, photosensitive resin composition for projection exposure and photosensitive element

1. A method for forming a resist pattern comprising:

a step of forming a photosensitive resin layer on a substrate using a photosensitive resin composition for projection exposure;

a step of exposing the photosensitive resin layer to active light projecting an image of a photomask through a lens; and

a step of removing an unexposed part of the photosensitive resin layer from the substrate by development;

wherein the photosensitive resin composition for projection exposure comprises an (A) binder polymer, a (B) photopolymerizing compound having an ethylenically unsaturated bond, a (C) photopolymerization initiator, and a (D) sensitizing dye comprising a pyrazoline, wherein a content of the (D) sensitizing dye in the photosensitive resin composition is 0.01 to 0.02 parts by mass with respect to 100 parts by mass as the total of the (A) binder polymer, and the (B) photopolymerizing compound having an ethylenically unsaturated bond; and

a light transmittance of the photosensitive resin layer at a wavelength of 365 nm is not less than 58.0% and not more than 95.0%.

2. The method for forming a resist pattern according to claim 1 , wherein a content of the (C) photopolymerization initiator in the photosensitive resin composition is 0.01 to 30 parts by mass with respect to 100 parts by mass as the total of the (A) binder polymer and the (B) photopolymerizing compound having an ethylenically unsaturated bond.

3. A method for manufacturing a printed wiring board comprising a step of forming a conductor pattern by performing an etching treatment or a plating treatment on a substrate with a resist pattern formed by the method for forming a resist pattern according to claim 1 .

4. The method for forming a resist pattern according to claim 1 , wherein the (D) sensitizing dye is a pyrazoline.

5. The method for forming a resist pattern according to claim 4 , wherein the (D) sensitizing dye is a compound expressed by the following general (III):

wherein R 8 represents an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms; a, b and c represent independently an integer of 0 to 5, the sum total of a, b and c is 1 to 6, and, if the sum total of a, b and c is 2 to 6, a plurality of R 8 in the same molecule may be the same or different.

6. The method for forming a resist pattern according to claim 5 , wherein at least one of R 8 is an alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 10 carbon atoms.

7. The method for forming a resist pattern according to claim 5 , wherein at least one of R 8 is an alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 5 carbon atoms.

8. The method for forming a resist pattern according to claim 5 , wherein at least one of R 8 is an isopropyl group or a methoxy group.

9. The method for forming a resist pattern according to claim 1 , wherein the pyrazoline is a compound expressed by the following general (III):

wherein R 8 represents an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms; a, b and c represent independently an integer of 0 to 5, the sum total of a, b and c is 1 to 6, and, if the sum total of a, b and c is 2 to 6, a plurality of R 8 in the same molecule may be the same or different.

10. The method for forming a resist pattern according to claim 9 , wherein at least one of R 8 is an alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 10 carbon atoms.

11. The method for forming a resist pattern according to claim 9 , wherein at least one of R 8 is an alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 5 carbon atoms.

12. The method for forming a resist pattern according to claim 9 , wherein at least one of R 8 is an isopropyl group or a methoxy group.