THE PRESENT INVENTION RELATES TO A METHOD FOR PRODUCING AN AQUEOUS α-SF SALT SOLUTION THAT MAINTAINS FLUIDITY AND HAS SUPERIOR PRODUCTION ADAPTABILITY. THE METHOD INCLUDES DISSOLVING A SOLID COMPONENT (A) IN THE FORM OF AN α-SULFO FATTY ACID ALKY ESTER SALT AND A COMPONENT (B) IN THE FORM OF AN INORGANIC SODIUM SALT AND/OR INORGANIC POTASSIUM SALT IN WATER WHEREIN COMPONENT (A) IS DISSOLVED IN THE WATER UNDER TEMPERATURE CONDITIONS OF 50°C OR HIGHER WHILE MAINTAINING THE FOLLOWING CONDITION (I) OR (II): (I): THE CONCENTRATION OF THE COMPONENT (A) IS 35% BY WEIGHT 15 OR LESS IN THE CASE THE TOTAL CONCENTRATION OF SODIUM IONS AND POTASSIUM IONS DERIVED FROM THE COMPONENT (B) IS LESS THAN 0.55 MOL/KG, OR (II) THE CONCENTRATION OF THE COMPONENT (A) IS 55% BY WEIGHT OR LESS IN THE CASE THE TOTAL CONCENTRATION OF SODIUM AND POTASSIUM IONS DERIVED FROM THE COMPONENT (B) IS 0.55 MOL/KG TO LESS THAN 1.8 MOL/KG.
