Negative photosensitive fluorinated aromatic resin composition

Abstract

The present invention provides a negative photosensitive fluorinated aromatic resin composition having a low relative permittivity, low water absorptivity, high heat resistance and high productivity. The composition includes a photosensitizer, a solvent and a fluorinated aromatic prepolymer represented by the following formula (1): where the structural variables are described herein as well as methods of preparing the prepolymer.

1 . A negative photosensitive fluorinated aromatic resin composition comprising the following fluorinated aromatic prepolymer, at least one photosensitizer and at least one solvent:
 Fluorinated aromatic prepolymer: A fluorinated aromatic prepolymer which is obtained by subjecting either one or both of a compound (Y-1) having a crosslinkable functional group (A) and a phenolic hydroxyl group, and a compound (Y-2) having a crosslinkable functional group (A) and a fluorinated aromatic ring, to a condensation reaction in the presence of a HF-removing agent, with a fluorinated aromatic compound (B) represented by the following formula (1):   
       
         
           
           
               
               
           
         
         (wherein n is an integer of from 0 to 3, each of a and b which are independent of each other, is an integer of from 0 to 3, each of Rf1 and Rf2 which may be the same or different from each other, is a fluorinated alkyl group having at most 8 carbon atoms, and F in the aromatic ring represents that hydrogen atoms of the aromatic ring are all substituted by fluorine atoms), and a compound (C) having at least 3 phenolic hydroxyl groups, and which has crosslinkable functional groups (A) and ether bonds and has a number average molecular weight of from 1×103 to 5×105. 
       
     
     
         2 . The negative photosensitive fluorinated aromatic resin composition according to  claim 1 , wherein the photosensitizer is contained in an amount of from 0.1 to 30 parts by mass, based on 100 parts by mass of the fluorinated aromatic prepolymer. 
     
     
         3 . The negative photosensitive fluorinated aromatic resin composition according to  claim 1 , wherein the photosensitizer is a photo initiator, a photoacid generator, a photobase generator or a photocrosslinking agent. 
     
     
         4 . The negative photosensitive fluorinated aromatic resin composition according to  claim 1 , wherein the solvent is at least one member selected from the group consisting of an aromatic hydrocarbon, a dipolar aprotic solvent, a ketone, an ester, an ether or a halogenated hydrocarbon. 
     
     
         5 . The negative photosensitive fluorinated aromatic resin composition according to  claim 1 , wherein the HF-removing agent is sodium carbonate, potassium carbonate, sodium hydrogencarbonate, potassium hydrogencarbonate, sodium hydroxide or potassium hydroxide. 
     
     
         6 . The negative photosensitive fluorinated aromatic resin composition according to  claim 1 , wherein the compound (Y-1) or the compound (Y-2) is a phenol having a reactive double bond or triple bond, or a fluorinated aryl having a reactive double bond or triple bond. 
     
     
         7 . The negative photosensitive fluorinated aromatic resin composition according to  claim 1 , wherein the fluorinated aromatic compound (B) is perfluorotoluene, perfluorobiphenyl, perfluoro(1,3,5-triphenylbenzene) or perfluoro(1,2,4-triphenylbenzene). 
     
     
         8 . The negative photosensitive fluorinated aromatic resin composition according to  claim 1 , wherein the compound (C) is trihydroxybenzene or 1,1,1-tris(4-hydroxyphenyl)ethane. 
     
     
         9 - 10 . (canceled) 
     
     
         11 . A method of making the negative photosensitive fluorinated aromatic resin composition according to  claim 1 , comprising combining the fluorinated aromatic prepolymer, photosensitizer and solvent.