Water vapor permeability tester: the core technology for testing the performance of packaging materials
The water vapor transmission rate of packaging materials is a crucial indicator in the packaging process of many products. It directly affects the quality, shelf life, and stability of the product. The water vapor permeability tester, as a professional equipment for precise measurement of this indicator, plays an irreplaceable role in multiple industries such as food, medicine, and cosmetics.
working principle
The working principle of the water vapor permeability tester is based on different technical methods, commonly including weighing method, infrared method, and electrolysis method.
The weighing method, also known as the "cup method". Under certain temperature and humidity conditions, a specific humidity difference is formed on both sides of the sample, and water vapor passes through the sample in the moisture permeable cup and enters the dry side. By accurately measuring the change in weight of the moisture permeable cup over time, parameters such as the water vapor transmission rate of the sample can be calculated. This method is a widely used approach for similar instruments in the market.
Infrared method is based on the working principle of infrared moisture sensors. During the testing process, the pre processed sample is clamped between the testing chambers, forming two chambers with stable relative humidity on the high humidity side and low humidity side. On the high humidity side, nitrogen carries a certain amount of water vapor, while on the low humidity side, dry nitrogen flows. Due to the difference in humidity, water vapor will diffuse from the high humidity side through the film or material sample to the low humidity side. The water vapor that passes through the low humidity side is carried by the flowing dry nitrogen gas to the infrared moisture sensor. Different concentrations of water vapor will generate different light signals in infrared sensors. By analyzing and calculating these light signals, the water vapor transmittance of the sample can be obtained.
The electrolysis method utilizes the principle of an electrolytic cell. When water vapor passes through the sample and enters the electrolytic cell, it is electrolyzed into hydrogen and oxygen. By measuring the current generated during the electrolysis process, the water vapor transmission rate can be calculated.
Features
1. High precision measurement: Using advanced sensors and precise measurement technology, it can provide high-precision measurement results of water vapor transmission rate. Both low transmittance high barrier materials and high transmittance ordinary materials can be accurately measured.
2. Wide range testing: With a wide measurement range, it can meet the testing needs of different types of packaging materials. For example, the measurement range of some instruments is usually 0.01-1200g/m ² · 24h, and a wider range can be selected as needed, such as 0.01-7500g/m ² · 24h.
3. Accurate temperature and humidity control: With precise temperature and humidity control functions, it can simulate different environmental conditions, such as temperature can be accurately controlled within the range of 5-95 ℃, humidity can be set to various different humidity conditions such as 0% RH, 35% RH-90% RH, 100% RH, etc., to meet the testing needs of various practical application scenarios.
4. Multi sample testing: Some instruments have the function of multi sample testing. Some instruments can simultaneously test multiple samples, greatly improving testing efficiency, reducing testing time and costs.
5. Data processing and recording: Equipped with professional data processing software, it can automatically record and analyze test data, and generate detailed test reports. It can also store, print, and transmit data, facilitating users' subsequent analysis and management.
6. Easy to operate: The user interface design is user-friendly and easy to operate. Even operators without professional technical background can proficiently use instruments for testing after simple training.
Application field
1. Food packaging industry: For food packaging materials, the water vapor transmission rate directly affects the shelf life and quality of food. By testing the water vapor transmission rate of packaging materials, food production enterprises can choose suitable packaging materials to ensure that food is not damp or spoiled during storage and transportation.
2. Pharmaceutical packaging industry: The stability of drugs is crucial for their quality and efficacy. Water vapor may cause drugs to become damp, decompose, or deteriorate, so the water vapor transmission rate of drug packaging materials must be strictly controlled. The water vapor permeability tester can help pharmaceutical manufacturers test the performance of packaging materials, ensuring the quality and safety of drugs.
3. Cosmetics industry: Some ingredients in cosmetics may be sensitive to moisture, and excessive water vapor transmission can cause changes in the texture, color, and efficacy of cosmetics. The use of a water vapor permeability tester can screen for suitable packaging materials and extend the shelf life of cosmetics.
4. Other industries: In industries such as building materials, textiles, and electronics, water vapor permeability testers are also widely used. For example, the water vapor permeability of building materials affects the moisture resistance of buildings; The moisture permeability of textiles affects the comfort of wearing; The packaging materials of electronic products need to control the entry of water vapor to prevent electronic components from being damaged by moisture.
Technological development trends
With the continuous advancement of technology, water vapor permeability testers are also constantly developing and innovating. In the future, instruments will develop towards higher precision, intelligence, and convenience. In terms of high precision, continuous breakthroughs in sensor technology will further improve measurement accuracy and enable the detection of even smaller changes in water vapor transmission rate. In terms of intelligence, the instrument will have functions such as automatic calibration, automatic fault diagnosis, and automatic optimization of test parameters, reducing human operation errors and improving testing efficiency and reliability. In terms of convenience, the instrument will be smaller in size and lighter in weight, making it easier to carry and test on site. At the same time, the operation will be simpler and more intuitive, further reducing the threshold for use.
The water vapor permeability tester, as the core equipment for testing the performance of packaging materials, plays an important role in ensuring product quality and extending product shelf life. With the continuous development of technology, it will provide stronger support for the development of various industries and promote the continuous progress of packaging material technology.