Ink for screen printing

Abstract

Provided is an ink for use in electronic component production making use of screen printing, which is suitable for actually allowing fine lines with high precision to be drawn in screen printing, and for actually allowing successive screen printing operations to be performed. The ink for screen printing of the present invention includes surface-modified silver nanoparticles (A) and a solvent (B), and has a viscosity at a shear rate of 10 (1/s) and 25° C. of 60 Pa·s or more. The surface-modified silver nanoparticles (A) each include a silver nanoparticle and an amine-containing protective agent coating the silver nanoparticle. The solvent (B) includes at least a terpene solvent. In solvent (B), a content of solvents having a boiling point of less than 130° C. is 20 wt % or less based on the total amount of solvents.

1 . An ink for screen printing, comprising surface-modified silver nanoparticles (A) and a solvent (B), and having a viscosity at a shear rate of 10 (1/s) and 25° C. of 60 Pa·s or more,
 the surface-modified silver nanoparticles (A) each comprising a silver nanoparticle, and an amine-containing protective agent coating a surface of the silver nanoparticle, 
 the solvent (B) comprising a terpene solvent and a glycol ether solvent having a boiling point of 130° C. or more, a content of solvents having a boiling point of less than 130° C., in the solvent (B), being 20 wt % or less based on the total amount of solvents. 
 
     
     
         2 . The ink for screen printing according to  claim 1 , wherein the protective agent comprises, as the amine, an aliphatic monoamine (1) containing 6 or more carbon atoms in total, and at least one of an aliphatic monoamine (2) containing 5 or less carbon atoms in total and an aliphatic diamine (3) containing 8 or less carbon atoms in total. 
     
     
         3 . The ink for screen printing according to  claim 2 , wherein the aliphatic monoamine (1) containing 6 or more carbon atoms in total is a monoamine containing 6 to 18 carbon atoms in total and having a straight-chain alkyl group, and/or a monoamine containing 6 to 16 carbon atoms in total and having a branched-chain alkyl group. 
     
     
         4 . The ink for screen printing according to  claim 2 , wherein the aliphatic monoamine (2) containing 5 or less carbon atoms in total is a monoamine containing 2 to 5 carbon atoms in total and having a straight-chain or branched-chain alkyl group. 
     
     
         5 . The ink for screen printing according to  claim 2 , wherein the aliphatic diamine (3) containing 8 or less carbon atoms in total is a diamine containing 1 to 8 carbon atoms in total and represented by the following formula (a-2): 
       
         
           
           
               
               
           
         
         wherein R 4  and R 5  are the same or different, and are each a straight-chain or branched-chain alkyl group; R 6  and R 7  are each a hydrogen atom; and R 8  is a straight-chain or branched-chain alkylene group. 
       
     
     
         6 . The ink for screen printing according to  claim 1 , wherein the terpene solvent has a boiling point of 130° C. or more and a viscosity at 20° C. of 50 to 250 mPa·s. 
     
     
         7 . The ink for screen printing according to  claim 1 , wherein the glycol ether solvent comprises a compound represented by the following formula (b):
   R 11 —(O—R 13 ) m —OR 12   (b)
   wherein R 11  and R 12  are the same or different, and each represent an alkyl group or an acyl group; R 13  represents an alkylene group containing 1 to 6 carbon atoms; and m represents an integer of 1 or more.   
     
     
         8 . The ink for screen printing according to  claim 1 , further comprising a binder resin (C). 
     
     
         9 . The ink for screen printing according to  claim 1 , wherein a sintered body obtained by sintering the ink at 120° C. for 30 minutes has a volume resistivity of 10 μΩcm or less. 
     
     
         10 . A method for producing an electronic device, comprising the steps of applying the ink for screen printing according to  claim 1  on a substrate by screen printing, and sintering the ink. 
     
     
         11 . An electronic device comprising a substrate and a sintered body of the ink for screen printing according to  claim 1  disposed on the substrate.