Lithographic printing plate precursors and method of use

A method for preparing a lithographic printing plate precursor, comprising, in order:

• providing an aluminum-containing plate having an electrochemically or mechanically grained and etched surface;
• subjecting the aluminum-containing plate to a first anodizing process to form an outer aluminum oxide layer on the electrochemically or mechanically grained and etched surface, the outer aluminum oxide layer comprising a multiplicity of outer micropores having an average outer micropore diameter (Do) of at least 15 nm and up to and including 30 nm, and having an average dry thickness (To) of at least 30 nm and up to and including 650 nm;
• rinsing the outer aluminum oxide layer;
• subjecting the aluminum-containing plate to a second anodizing process to form an inner aluminum oxide layer underneath the outer aluminum oxide layer, the inner aluminum oxide layer having an average dry thickness (Ti) of at least nm and up to and including 3,000 nm;
• and comprising a multiplicity of inner micropores having an average inner micropore diameter (Di) of less than or equal to 100 nm;
• rinsing the outer aluminum oxide layer and the inner aluminum oxide layer;
• forming an on-press developable radiation-sensitive imageable layer over the outer aluminum oxide layer;
• and
• after rinsing the outer aluminum oxide layer and the inner aluminum oxide layer, and before forming the on-press developable radiation-sensitive imageable layer over the outer aluminum oxide layer, providing a hydrophilic layer over the outer aluminum oxide layer, the hydrophilic layer comprising:
• (1) a compound having one or more ethylenically unsaturated polymerizable groups, one or more —OM groups at least one of which is connected directly to a phosphorus atom, and a molecular weight of less than 2000 Daltons/mole, wherein M represents a hydrogen, sodium potassium, or aluminum atom, and
• (2) one or more hydrophilic polymers, each comprising at least (a) recurring units comprising an amide unit, and (b) recurring units comprising an —OM′ group that is directly connected to a phosphorus atom, wherein M′ represents a hydrogen, sodium, potassium, or aluminum atom, and
• which hydrophilic layer is disposed over the outer aluminum oxide layer at a dry coverage of at least 0.0002 g/m2 and up to and including 0.1 g/m2.