sipat Uap-bukti aluminium foil

sipat Uap-bukti aluminium foil

Aluminium foil miboga sipat tahan-lembab anu alus. Sanajan pinholes inevitably bakal muncul nalika ketebalan tina aluminium foil kirang ti 0.025mm., lamun dititénan ngalawan cahaya, the moisture-proof properties of aluminium foil with pinholes are much stronger than those of plastic films without pinholes. This is because the polymer chains of plastics are widely spaced apart from each other and cannot prevent water vapor from penetrating.

Moisture permeability of aluminum foil and plastic films

Material typeMoisture permeability/g·(m2·24h)-1Material typeMoisture permeability/g·(m2·24h)-1
0.009mm plain aluminum foil1.08~10.700.09mm polyethylene7
0.013mm plain aluminum box0.60~4.800.1mm polyethylene4.8
0.018 mm plain aluminum foil0~1.240.02mm PVC157
0.025mm plain aluminum foil0~0.460.065mm PVC28.4
0.03~0.15mm00.095mm PVC41.2
plain foil cellophane50~70//

When the thickness of aluminum foil is small enough, pinholes will inevitably appear. The minimum thickness for pinholes is generally considered to be 0.038mm. Due to improvements in rolling technology and materials, this thickness has been reduced to 0.025mm. Tests have also proven that the vent diameter is critical. When the diameter is less than 5um, oxygen and water vapor are not transmitted within the measurable range.