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How do lipids in the stratum corneum prevent water loss through skin?

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A pangolin walks through grass with a blue circle around it and the word endangered written in white across the image. — Integument The pangolin is the only mammal in the world covered in scales.

In the human skin, the stratum corneum acts as a vital barrier against the outward loss of water and the inward passage of chemicals. This protective function is located specifically within a compact zone in the lower part of the horny layer.12

Within this region, the spaces between the flattened, keratin-filled cells are tightly packed with lamellae, or platelets, of waxy lipids. These lipids are produced inside membrane-coating granules within the underlying living epidermal cells. As these cells move toward the surface, the granules migrate to the cell periphery and discharge their waxy components into the intercellular spaces. By filling the gaps between the cornified cells with these hydrophobic, waxy materials, the skin creates an effective seal that prevents moisture from escaping the body.123