Internal Bond

Product Description Property/Function Catalog #

ZDT Tester

There are several methods developed to measure internal bond strength or delamination strength of paper and board. The most common are the Scott type internal bond strength which is a dynamic impact test based on the energy stored when a pendulum is released. A second method is the z-directional tensile strength. ZDT measures the tensile strength of a specimen which is sandwiched and compressed between two adhesive tapes. After compression, the specimen is separated to determine the maximum force at rupture.

Internal Bond


Internal Bond Tester and Prep Station

The Internal Bond™ Tester is designed to determine the internal bond strength of a variety of Paper and Board materials according to TAPPI T 569. The instrument design is based on a falling pendulum which creates a high speed impact on a paper specimen. The paper specimen is sandwiched between two double-coated tape substrates. The pendulum impact measures the total energy required to delaminate the internal fibers of a specimen in a “Z” type direction into two separate piles. The system also incorporates an automatic sample preparation station which allows five specimens to be accurately prepared simultaneously. The Prep Station requires a filtered air supply meeting IG4 Industrial Grade Air: ISO Class 1-4-1.

Internal Bond


Lab Master® Z-Directional Tensile Tester

The measurement of Z-Directional tensile strength was developed to determine the structure of a sheet of paper or board when subjected to tensile stresses in the out-of-plane direction or Z-Direction. Z-Directional Tensile Strength is a measure of the internal fiber bonding strength of a substrate.

Internal Bond


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