Method for producing abrasive grains, method for producing slurry, and method for producing polishing liquid

Abstract

In the production method for abrasive grains according to the invention, an aqueous solution of a salt of a tetravalent metal element is mixed with an alkali solution, under conditions such that a prescribed parameter is 5.00 or greater, to obtain abrasive grains including a hydroxide of the tetravalent metal element.

1 - 15 . (canceled) 
     
     
         16 . An abrasive grain obtained by mixing a first liquid which is an aqueous solution of salt of a tetravalent metal element with a second liquid which is an alkali solution, under conditions such that parameter Z in the following formula (1) is 5.00 or greater, the abrasive grain including a hydroxide of the tetravalent metal element.
     Z=[ 1/(ΔpH× k )]×( N/M )/1000  (1)
   
       [In formula (1), ΔpH represents a variation in pH per minute in a reaction system, k represents a reaction temperature coefficient represented by the following formula (2), N represents a cycle count (min −1 ) represented by the following formula (3), and M represents a substitution count (min −1 ) represented by the following formula (5).]
     k= 2 [(T-20)/10]   (2)
 
 
       [In formula (2), T represents a temperature (° C.) of the reaction system.]
     N =( u×S )/ Q   (3)
 
 
       [In formula (3), u represents a linear speed (m/min) represented by the following formula (4), for a stirring blade stirring a liquid mixture obtained by mixing the first liquid and the second liquid, S represents an area (m 2 ) of the stirring blade, and Q represents a liquid volume (m 3 ) of the liquid mixture.]
     u= 2 π×R×r   (4)
 
 
       [In formula (4), R represents a rotational speed (min −1 ) of the stirring blade, and r represents a radius of rotation (m) of the stirring blade.]
     M=v/Q   (5)
 
 
       [In formula (5), v represents a mixing rate (m 3 /min) of the first liquid and the second liquid, and Q represents a liquid volume (m 3 ) of the liquid mixture.] 
     
     
         17 . The abrasive grain according to  claim 16 , wherein the ΔpH is not greater than 5.00. 
     
     
         18 . The abrasive grain according to  claim 16 , wherein the cycle count N is 1.00 min −1  or greater. 
     
     
         19 . The abrasive grain according to  claim 16 , wherein the substitution count M is not greater than 1.0 min −1 . 
     
     
         20 . The abrasive grain according to  claim 16 , wherein the linear speed u is 5.00 m/min or greater. 
     
     
         21 . The abrasive grain according to  claim 16 , wherein the mixing rate v is not greater than 1.00×10 −2  m 3 /min. 
     
     
         22 . The abrasive grain according to  claim 16 , wherein the rotational speed R is 30 min −1  or greater. 
     
     
         23 . The abrasive grain according to  claim 16 , wherein the temperature T is not higher than 60° C. 
     
     
         24 . The abrasive grain according to  claim 16 , wherein a concentration of the salt of a tetravalent metal element in the first liquid is 0.01 mol/L or greater. 
     
     
         25 . The abrasive grain according to  claim 16 , wherein an alkaline concentration of the second liquid is not greater than 15.0 mol/L. 
     
     
         26 . The abrasive grain according to  claim 16 , wherein a pH of the liquid mixture is 2.0 to 7.0. 
     
     
         27 . The abrasive grain according to  claim 16 , wherein the tetravalent metal element is tetravalent cerium. 
     
     
         28 . A slurry obtained by mixing the abrasive grain according to  claim 16  with water. 
     
     
         29 . A polishing liquid obtained by mixing the slurry according to  claim 28  with an additive. 
     
     
         30 . A polishing liquid obtained by mixing the abrasive grain according to  claim 16 , an additive and water. 
     
     
         31 . A slurry obtained by mixing the abrasive grain according to claim  27  with water. 
     
     
         32 . A polishing liquid obtained by mixing the slurry according to  claim 31  with an additive. 
     
     
         33 . A polishing liquid obtained by mixing the abrasive grain according to  claim 27 , an additive and water.