Layering in Rice Packaging

For packaging 5kg of rice, how many layers should we use in the bag? Is a 2-layer sufficient, or should we go for 3-layer or more? The layers must provide proper protection against moisture, air, and light, so how thick should each layer be? What's the best combination of layers to ensure that the rice stays safe and fresh during storage and transportation?

docs.......

Rice doesn't require a resistance of light.
PA/LDPE is OK.
Sometimes, PET/LDPE is also OK for a cost-sensitive customer.