This standard establishes the classification system, the qualification and quality conformance requirements for flexible metal-clad dielectric materials to be used for the fabrication of flexible printed circuitry and flexible flat cable.

Classification System The system described in 1.1.1 through 1.1.2.7 identifies flexible metal-clad dielectrics.

Nonspecific Designation A nonspecific designation is intended for use by designers on master drawings to designate their material choice. At the end of this standard is a series of material specification sheets identified by specification sheet numbers. Each sheet outlines engineering and performance data for a flexible metal-clad dielectrics, indicating base material type, adhesive type and method of reinforcement.

Example of nonspecific designation:

IPC-4204/1, where ‘‘1'' refers to the specification sheet detailing copper-clad polyimide dielectric with acrylic adhesive. If further material specification details (such as dielectric, adhesive or copper thicknesses) are required, they should be highlighted in cross sectional views or notes on the master drawing.

Specific Designation The specific designation should be in the form shown in the following example, and is intended for use on material purchase orders by fabricators (see 6.1). The specific designation should not be used by designers on master drawings to indicate their material selection, as the designation is lengthy and requires fabricator level knowledge in making the detailed selections.