Chemical conversion treatment liquid and production method for member having surface provided with chemical conversion film

A chemical conversion treatment liquid that is cobalt-free and contains a water-soluble trivalent chromium-containing substance, a water-soluble titanium-containing substance, and a water-soluble lactic acid-containing substance as essential components,

• the chemical conversion treatment liquid optionally containing a component at least a part of which is any of a water-soluble glycolic acid-containing substance and a water-soluble ineffective organic acid-containing substance, the water-soluble ineffective organic acid-containing substance being a water-soluble organic acid-containing substance based on an ineffective organic acid that is an organic acid other than lactic acid and other than glycolic acid,
• wherein (I) when the chemical conversion treatment liquid does not contain the water-soluble glycolic acid-containing substance and does not contain the water-soluble ineffective organic acid-containing substance,
• a titanium-equivalent molar concentration CTi of the water-soluble titanium-containing substance, a chromium-equivalent molar concentration CCr of the water-soluble trivalent chromium-containing substance, and a lactic acid-equivalent molar concentration CLc of the water-soluble lactic acid-containing substance satisfy following Expressions (1) to (3):
• wherein (II) when the chemical conversion treatment liquid contains the water-soluble glycolic acid-containing substance and does not contain the water-soluble ineffective organic acid-containing substance,
• the above Expressions (1) and (3) and a following Expression (2A) are satisfied:
• (
• CLc
• -
• α
• ×
• CGy)/(CTi+CCr)
• ≥
• 0
• .40
• where CGy represents a glycolic acid-equivalent molar concentration of the water-soluble glycolic acid-containing substance and α represents a correction coefficient of 0.4,
• wherein (III) when the chemical conversion treatment liquid does not contain the water-soluble glycolic acid-containing substance and contains the water-soluble ineffective organic acid-containing substance,
• the above Expressions (1) to (3) and a following Expression (4) are satisfied:
• 0
• <
• CCa/CLc
• ≤
• 0
• .175
• where CCa represents an organic acid-equivalent molar concentration of the water-soluble ineffective organic acid-containing substance,
• wherein (IV) when the chemical conversion treatment liquid contains the water-soluble glycolic acid-containing substance and contains the water-soluble ineffective organic acid-containing substance,
• the above Expressions (1), (2A), (3), and (4) are satisfied.