Patent ID: 8173588

Claim:
A solid composition comprising an iminocarboxylic acid compound, wherein the iminocarboxylic acid compound is 3-hydroxy-2,2′-iminodisuccinic acid and/or a salt thereof, the solid composition comprises 70% by weight or more and 90.5% by weight or less of the iminocarboxylic acid compound, relative to a solid content except for moisture of the solid composition, and the solid composition comprises 20% by weight or less of moisture, relative to the solid composition, and wherein an isomer ratio (a D-form/L-form molar ratio) of an aspartic acid skeleton of the iminocarboxylic acid compound is 0/1 to 0.3/0.7 or 1/0 to 0.7/0.3, and wherein the solid composition has a particle size of 0.1 μm to 100 μm and wherein the solid composition is obtainable by a method comprising a drying step using spray drying equipment, and wherein said composition has 0.6 mg/sec or more of a dissolution ratio calculated from the following formula, at 5° C.: Dissolution rate=(charged powder composition (mg))/time taken for dissolution (sec)).