ASTM International

Standard Practices for Making Heatseals for Determination of Heatsealability of Flexible Webs as Measured by Seal Strength
 N F2029

Annotation

These practices cover laboratory preparation of heat-sealsand the treatment and evaluation of heatseal strength data for the purpose of determining heatsealability of flexible barrier materials.

Testing strength or other properties of the heatseals formed by these practices is not included in this standard. Refer to Test Methods F 88 for testing heatseal strength.

The practices of this standard are restricted to sealing with a machine employing hot-bar jaws. Impulse, high-frequency, and ultrasonic heating methods are not included.

These practices apply primarily to webs intended to be used on commercial machines employing reciprocating sealing jaws, such as most vertical form-fill packaging machines, platen heatsealers, etc. Conditions of dwell time and sealing pressure on machines of this type typically are different from those on rotary machines by an order of magnitude or more.

The procedures of these practices with respect to choice of heatsealing conditions apply equally whether the application is to ultimate seal strength or hot tack measurement.

Seals may be made between webs of the same or dissimilar materials. The individual webs may be homogeneous in structure or multilayered (coextruded, coated, laminated, etc.).

Strength of the heatseal is the criterion for judging heatsealability employed in these practices.

Determination of heatsealability as judged by seal continuity, typically measured by air-leak, dye penetration, visual examination, microorganism penetration or other techniques, are not covered by these practices.