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Oxygen Transmission Performance for Contact Lenses

Oxygen Transmission Performance for Contact Lenses
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Oxygen Transmission Performance for Contact Lenses - 1

Contact: Yarina Gao Email: trade5@labthink.cn Phone:086-531-85060139 Oxygen Transmission Performance for Contact Lenses It’s well-known that the oxygen transmission performance of contact lenses would directly influence the feelings and experiences of the consumers, and the sales volume would be affected correspondingly. Therefore, the test for oxygen permeation performance of contact lens has become a main concern of the manufacturers. Owing to the importance of oxygen transmission performance of contact lenses, ISO, International Standard Organization, has formulated two relevant testing standards as follows: ISO 9913-1, Optics and optical instruments—Contact lenses—Part 1: Determination of oxygen permeability and transmissibility with the FATT method; and ISO 9913-2, Optics and optical instruments—Contact lenses—Part 2: Determination of oxygen permeability and transmissibility by the coulometric method . The testing principle and instrument of ISO 9913-2 are similar to those of coulometric method applied in oxygen transmission rate tests for flexible packaging materials. The testing principle is as shown in Fig. 1. Testing principle Place the sample to be tested into the testing chamber, and the chamber would be separated into two sections: upper chamber and lower chamber. Then, testing gas with a certain oxygen concentration is purged into the upper chamber. Carrier gas flow, that is, nitrogen gas flow, purges into the coulometric sensor through the lower chamber. Though the pressures of the upper chamber and the lower chamber are the Contact: Yarina Gao Email: trade5@labthink.cn Phone:086-531-85060139

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Oxygen Transmission Performance for Contact Lenses - 2

Contact: Yarina Gao Email: trade5@labthink.cn Phone:086-531-85060139 same, the pressures of oxygen differ in them. Thus, oxygen would, with the help of concentration difference, permeate through the sample and into the carrier gas side. Then, oxygen would be taken to the coulometric sensor. The sensor would precisely measure the oxygen quantity in the carrier gas flow (that is, nitrogen gas flow), and calculate the oxygen transmission rate (OTR). It can be concluded, from the above-mentioned principle, that oxygen transmission performance tests for contact lenses and flexible packaging...

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Oxygen Transmission Performance for Contact Lenses - 3

Contact: Yarina Gao Email: trade5@labthink.cn Phone:086-531-85060139 clamping accessories and temperature control device for oxygen transmission tests of contact lenses. Labthink also has some other equipments that can be used to test the Oxygen Transmission Rate or Gas permeability Test Please go to our website for more details about our products. Contact: Yarina Gao Email: trade5@labthink.cn Phone:086-531-85060139

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