Negative photosensitive resin composition, cured resin film, partition walls and optical element

1. A negative photosensitive resin composition comprising:

(A) an alkali-soluble resin or alkali-soluble monomer, which has a photo-curability,

(B) a photopolymerization initiator, and

(C) an ink repellent agent which has a fluorine atom content of at least 1 mass % and less than 10 mass % and which is a partially hydrolyzed condensate of a hydrolyzable silane compound mixture containing a hydrolyzable silane compound (s1) having a hydrolyzable group and a C 2-40 monovalent group represented by R f1 OR f2 —, wherein R f1 is a C 1-6 polyfluoroalkyl group, and R f2 is a polyfluoroalkylene group which may have an etheric oxygen atom between carbon-carbon atoms, provided that R f1 OR f2 — has at least one —O—CF 2 — group.

2. The negative photosensitive resin composition according to claim 1 , wherein the hydrolyzable silane compound (s1) is a compound represented by the following formula (cx-1):

(R f1 OR f2 -Q 1 ) a -Si(R H1 ) b X 1 ( 4-a-b )  (cx-1)

where Q 1 represents a C 1-10 divalent organic group containing no fluorine atom,

R H1 represents a C 1-6 monovalent hydrocarbon group,

a represents 1 or 2, and b represents 0 or 1, provided a +b is 1 or 2, and

X l represents a hydrolyzable group.

3. The negative photosensitive resin composition according to claim 1 , wherein R f1 is a perfluoroalkyl group, and R f2 is a perfluoroalkylene group.

4. The negative photosensitive resin composition according to claim 1 , wherein the hydrolyzable silane compound mixture comprises a hydrolyzable silane compound (s2) having four hydrolyzable groups bonded to a silicon atom.

5. The negative photosensitive resin composition according to claim 1 , wherein the hydrolyzable silane compound mixture further comprises a hydrolyzable silane compound (s3) having a group containing an ethylenic double bond and a hydrolyzable group and containing no fluorine atoms.

6. The negative photosensitive resin composition according to claim 1 , wherein the fluorine atom content of the ink repellent agent (C) is at least 2 mass % and less than 10 mass %.

7. The negative photosensitive resin composition according to claim 1 , further comprising a cross-linking agent (D) having at least two ethylenic double bonds in one molecule and having no acidic group.

8. A resin film comprising a cured product of the negative photosensitive resin composition as defined in claim 1 .

9. The resin film according to claim 8 ,

wherein the resin film is formed on a substrate, and

in a composition analysis at a surface of the resin film and a composition analysis in an interior of the resin film in a thickness direction thereof by X-ray photoelectron spectroscopy (XPS),

at least at the surface of the resin film, peaks indicating a presence of silicon atoms and carbon atoms derived from —O—CF 2 — groups are measured,

a ratio of a concentration of carbon atoms derived from —O—CF 2 — groups to a concentration of carbon atoms derived from substituted or unsubstituted non-fluorinated hydrocarbon groups, at the surface of the resin film, [C FO /C H ](s), is larger than a ratio of a concentration of carbon atoms derived from —O—CF 2 — groups to a concentration of carbon atoms derived from substituted or unsubstituted non-fluorinated hydrocarbon groups, at the interior of the resin film, [C FO /C H ] (i) , and

a ratio of a concentration of silicon atoms to a concentration of carbon atoms derived from substituted or unsubstituted non-fluorinated hydrocarbon groups, at the surface of the resin film, [Si/C H ] (s) , is larger than a ratio of a concentration of silicon atoms to a concentration of carbon atoms derived from substituted or unsubstituted non-fluorinated hydrocarbon groups, at the interior of the resin film, [Si/C H ] (i) .

10. A partitioned substrate comprising:

a substrate; and

partition walls formed on a surface of the substrate to partition the surface into a plurality of compartments for forming dots and made of the resin film as defined in claim 8 .

11. An optical element comprising:

a substrate;

dots formed on a surface of the substrate; and

partition walls located between one of the dots and a dot adjacent to the one of the dots and formed of the resin film as defined in claim 9 .

12. The optical element according to claim 11 , wherein the dots are formed by an ink jet method.

13. The negative photosensitive resin composition according to claim 1 , wherein R f1 is a perfluoroalkyl group, and R f2 is a perfluoroalkylene group having an etheric oxygen atom.

14. The negative photosensitive resin composition according to claim 1 , wherein the fluorine atom content of the ink repellent agent (C) is at least 1 mass % and at most 8 mass %.