WVTR-Water Vapor Transmission Rate

WVTR is the abbreviation for water vapor transmission rate, which is defined as the constant rate at which water vapor permeates through a specimen film at specified conditions of temperature and relative humidity.

WVTR is of great significance for package quality. With the Water vapor transmission rate testing, effective quality control of food, drug and electronic products, etc. can be guaranteed so as to improve the storage, transportation and shelf life results and prolong shelf life span of the products.

The WVTR measurement is applicable for barrier property evaluation of plastic films, laminated films, sheets, back sheets, high barrier materials, foils, OLED, water-proof membranes and bottles, pouches, jars, boxes made of plastic, rubber, paper, glass and metal, as well as medical devices, etc.

The testing principle of WVTR is as follows: Mount the preconditioned specimen between the testing cells, clamp tightly. Nitrogen with constant humidity flows through one side of specimen, dry nitrogen flows through another side of the specimen. Under the function of humidity difference/grades, water vapor passes through the specimen and enters the lower humid side, and is carried to the sensor by the dry nitrogen. The electrical signals are generated at the sensor when the water vapor enters. Calculate the water vapor transmission rate by analyzing the electrical signals. For package test, dry nitrogen flows in the package, humid nitrogen flows around the outer side of the package.

Labthink Instruments Co., Ltd., as the leading transmission testing instrument manufacturer, devotes to providing excellent WVTR testing instruments. Recently, Labthink introduces innovative Labthink PERME W3/330 Water Vapor Permeability Tester. This tester is of master base and satellite module mode, which can effectively test 30 kinds of specimen simultaneously. This instruments complies with ISO 15106-3, GB/T 21529, DIN 53122-2, YBB 00092003 and other international standards.