5.1 Laminates are made by bonding together two or more layers of material or materials. Their performance is often dependent on the ability of the laminate to function as a single unit. If the plies have not been properly bonded together, the performance may be adversely affected. Laminates may maintain adequate bond strength under standard test conditions, but under conditions of use may exhibit an increase or decrease in bond strength. Applying heat, such as in boilable pouch applications, may adversely affect bond strength, as may cold temperatures, such as those encountered in freezer storage of foods. Fats and oils may also influence bond strength as well as the softness or moduli of the plies. This test method can be used to compare bond strength of similar materials and to study changes under these and other conditions of end use, providing caution is used with respect to the effects of the included force to bend the separated plies.

1.1 This test method covers a procedure for comparing the bond strength or ply adhesion of similar laminates made from flexible materials such as cellulose, paper, plastic film, and foil. This includes laminates made by various processes: adhesive laminates, extrusion coatings, extrusion laminates, and coextrusion.

1.2 Because of the impact of the bending force, direct comparisons between different materials or even between the same materials of different thickness cannot be made.

1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are provided for information purposes only.

1.4 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in 7.1.1.