Tuned polyethylenimine antipathogen film apparatus and method of use thereof

An apparatus for coating a substrate, comprising:

• an antimicrobial film on the substrate, comprising:
• a polyethylenimine, in a mass range of 0.1 to 5 mg per square inch, said polyethylenimine at least partially protonated;
• a polydiallyldimethylammonium salt;
• chloride counterions associated with protonated sites of said polyethylenimine;
• first conjugate base counterions, associated with said polyethylenimine, of a first organic acid, said first conjugate base counterions comprising a first mass of 0.001 to 0.1 mg per square inch;
• second conjugate base counterions, associated with said polyethylenimine, of a second organic acid, said second conjugate base counterions comprising a second mass of 0.05 to 1 mg per square inch;
• and
• a total cationic charge of said antimicrobial film in a range of 200 to 3000 C/m2, said total cationic charge countered by anions in said antimicrobial film,
• said antimicrobial film comprising an antimicrobial efficacy of greater than ninety percent according to PAS 2424:1024, a quantitative surface test for evaluation of residual antimicrobial efficacy of liquid chemical disinfectants on hard non-porous surfaces.