Paper-based materials must include an alkali reserve of at least 2% calcium carbonate (CaCO3). The alkali reserve has the ability to capture acids that may be in the air, the photograph, or in the material itself. Its useful life, however, is limited since it is consumed as it reacts with acid. IPI tests for alkali reserve of paper by soaking a sample in water, in the same manner as for the pH test, and then measuring the amount of acid necessary to neutralize the alkali buffering. This test determines the percent alkali reserve of the paper. Alkali reserves are added to paper and paperboards to neutralize acids that are created or absorbed as the paper deteriorates over time. All test results are confidential.
For the alkali reserve test, the customer shall provide IPI with 10 grams of each material submitted for testing. Please name or code your samples so that we have a reference by which to communicate the test results. Our test reports will refer only to your specific label.
The alkali reserve test is a destructive test; sample materials cannot be returned.
| Alkali Reserve Test | |
|---|---|
| First two samples inclusive (minimum charge) | $600 |
| Each additional samples (sent at same time) | $300 |
| Cold Extraction pH Test and Alkali Reserve Package | |
|---|---|
| First two samples inclusive (minimum charge) | $900 |
| Each additional samples (sent at same time) | $450 |