Production Method for Exhaust Gas Purification Catalyst and Chemical Solution Plate used in said Production Method

A method for producing an exhaust gas purification catalyst that purifies exhaust gas exhausted from an internal combustion engine, the method comprising:

• preparing a base material having an exhaust gas passage extending from an upstream end from which exhaust gas is introduced to a downstream end from which exhaust gas is exhausted;
• preparing a catalyst metal solution containing a catalyst metal functioning as a catalyst capable of oxidizing or reducing at least one exhaust gas component;
• supplying the catalyst metal solution to a chemical solution plate so that a bottom surface of the chemical solution plate is not exposed;
• immersing an upstream end or a downstream end of the base material in the catalyst metal solution supplied to the chemical solution plate to introduce the catalyst metal solution to an exhaust gas passage of the base material;
• and
• firing the base material into which the catalyst metal solution is introduced, wherein
• the bottom surface of the chemical solution plate is provided with grooves in a predetermined pattern, an average of depths of the grooves is from 1.2 mm to 3 mm inclusive, and an average of widths of the grooves is from 1.6 mm to 3 mm inclusive.