The strength and elongation properties of the loop yarn is mainly decided by the core yarn.

圈圈线的强伸性能主要由芯纱决定；

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The inner core yarn USES high performance fiber and outer wrapped yarn is a hot-melt fiber.

它是以高性能纤维为芯纱、热融纤维为包缠纱，通过二维编织工艺加工而成。

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The tensile strength of the core yarn is the highest, the second is the folded yarn, and the lowest is the wrapped yarn.

包芯纱具有较高的断裂强力，其次是平行纱，而包缠纱的最低；

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Baker tells me he can make a sock core just as cheaply as anyone in China or Honduras - the machine costs the same, so does the yarn, there's hardly any labor.

NPR: Alabama Town Questions an Economy of Socks