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.
About Labthink:
Labthink, the excellent provider of testing
instruments and testing services, is devoted to provide most excellent and
complete quality control solutions for pharmaceutical, foodstuff, cosmetics,
packaging, printing, adhesive, automotive, petrochemistry, environment,
biology, new energy, construction, aviation and electronic industries
worldwide.