Functional material, dispersion containing the functional material, and process for producing the functional material

Abstract

A functional material comprising fine coloring particles having an average primary particle diameter of 1 to 50 nm in a dried state, and having a BET specific surface area value of to 500 m 2 /g and a light transmittance of not less than 80%. The functional material composed of fine coloring particles, exhibits not only an excellent transparency but also a high tinting strength and a clear hue.

1 .- 2 . (canceled) 
     
     
         3 . A functional material comprising fine coloring particles having an average primary particle diameter of 1 to 50 nm in a dried state, and having a BET specific surface area value of 30 to 500 m 2 /g, a tinting strength of not less than 110% and a light transmittance of not less than 80% when evaluated by the following method:
 (1) blending 5 g of the functional material and the following components as a paint base material at the below-mentioned mixing ratio in a 250 ml glass bottle, and mixing and dispersing the resultant mixture together with 160 g of 3 mmφ glass beads using a paint shaker for 120 minutes, thereby preparing a paint:   
       
         
           
                 
                 
                 
               
                     
                     
                 
                     
                   Functional material 
                    9.9 parts by weight 
                 
                     
                   Melamine resin 
                   19.8 parts by weight 
                 
                     
                   Alkyd resin 
                   39.6 parts by weight 
                 
                     
                   Xylene 
                   29.7 parts by weight 
                 
                     
                   Butanol 
                    1.0 part by weight; 
                 
                     
                     
                 
             
                
               
               
                
                
                
                
                
                
               
            
           
         
         (2) applying the thus prepared paint onto a 100 μm-thick clear film to form a coating film having a thickness of 150 μm thereon; and 
         (3) measuring a light transmittance of the obtained coating film in a wavelength region of 380 to 700 nm using a self-recording photoelectric spectrophotometer; 
         produced by a process comprising: 
         mixing inorganic compound particles with a gluing agent under stirring to form a gluing agent coat on surface of the inorganic compound particles; 
         adding organic pigments to the inorganic compound particles coated with the gluing agent, and mixing the resultant mixture under stirring to adhere the organic pigments on the gluing agent coat, thereby obtaining composite particles; and 
         dissolving the inorganic compound particles only or both of the inorganic compound particles and the gluing agent from the composite particles. 
       
     
     
         4 .- 8 . (canceled) 
     
     
         9 . A process for producing a functional material comprising fine coloring particles, comprising:
 mixing inorganic compound particles with a gluing agent under stirring to form a gluing agent coat on surface of the inorganic compound particles;   adding organic pigments to the inorganic compound particles coated with the gluing agent, and mixing the resultant mixture under stirring to adhere the organic pigments on the gluing agent coat, thereby obtaining composite particles; and   dissolving the inorganic compound particles only or both of the inorganic compound particles and the gluing agent from the composite particles.