| WVTR is the abbreviation for water vapor | | | | paper, glass and metal, as well as medical devices, |
| transmission rate, which is defined as the constant | | | | etc. |
| rate at which water vapor permeates through a | | | | The testing principle of WVTR is as follows: Mount |
| specimen film at specified conditions of | | | | the preconditioned specimen between the testing |
| temperature and relative humidity. | | | | cells, clamp tightly. Nitrogen with constant |
| WVTR is of great significance for package quality. | | | | humidity flows through one side of specimen, dry |
| With the Water vapor transmission rate testing, | | | | nitrogen flows through another side of the |
| effective quality control of food, drug and | | | | specimen. Under the function of humidity |
| electronic products, etc. can be guaranteed so as | | | | difference/grades, water vapor passes through |
| to improve the storage, transportation and shelf | | | | the specimen and enters the lower humid side, |
| life results and prolong shelf life span of the | | | | and is carried to the sensor by the dry nitrogen. |
| products. | | | | The electrical signals are generated at the sensor |
| The WVTR measurement is applicable for barrier | | | | when the water vapor enters. Calculate the |
| property evaluation of plastic films, laminated | | | | water vapor transmission rate by analyzing the |
| films, sheets, back sheets, high barrier materials, | | | | electrical signals. For package test, dry nitrogen |
| foils, OLED, water-proof membranes and bottles, | | | | flows in the package, humid nitrogen flows around |
| pouches, jars, boxes made of plastic, rubber, | | | | the outer side of the package. |