Food packaging bag (roll film) : it has good water, oxygen and light barrier properties, suitable for candies, biscuits, milk powder, chocolate, puffed food products.

食品包装复合袋(卷膜)：具有良好的水份、氧气及光线阻隔性，适合于糖果、饼干、奶粉、巧克力、膨化食品等产品。

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Then the researchers came up with the idea of a light barrier.

FORBES: Using A Light Barrier To Repel Mosquitoes

Some scientists have long thought there might be a way to surpass the light barrier, and if so, certain limited kinds of time travel might be possible.

FORBES: Light's Limit: There's No Getting Around It

The bill has proposed a definition of a high hedge at two metres, formed by a row or two of evergreens, such as the fast-growing leylandii, which forms a barrier to light.

BBC: High hedge bill is intended to reduce disputes