Applying polyester onto metal substrate

Processing steps for laminating a metal substrate with a thermoplastic polymer film to create desirable simultaneous commercial properties comprising:

• a. uncoiling a metal substrate from a coil on a processing line,
• b. wherein said metal substrate is flat rolled,
• c. cleaning a first major side and a second major side of said metal surface,
• d. increasing the surface energy of said first major side of said metal substrate by use of surface energy pretreatment equipment,
• e. preheating said metal substrate to at least 200° F.,
• f. preselecting a first film for bonding to said first major side, wherein said first film is either solid or molten,
• g. pressing said first film onto said first major side by use of a first roll,
• h. utilizing a first chemical bond for adhering said first film to said first major side thereby creating a metal polymer laminate,
• i. wherein said first film comprises at least 50% thermoplastic polyester by weight,
• j. wherein said polyester is PET, PBT, or a mixture of PET and PBT,
• k. wherein said first film comprises at least one layer,
• l. post treating said metal polymer laminate by heating said metal polymer laminate to at least the lowest melting point of any polymer in said first film, and
• m. cooling said metal polymer laminate to below 150° F. for coiling into a finished coil,
• n. wherein said cooling of said metal polymer laminate creates crystallinity in said first film according to a predetermined criterion, and
• whereby said finished coil has said desirable simultaneous commercial properties comprising:
• o. coating continuity of at least three metal thickness bending radius without metal exposure,
• p. bonding of said first film onto said metal substrate of at least 43 ounces per inch after said cooling,
• q. a minimum pencil hardness of 2B.