Moire (fabric)

In textiles, a moire (/ˈmwɑːr/ or /ˈmɔːr/), less often moiré, is a fabric with a wavy (watered) appearance produced mainly from silk, but also wool, cotton and rayon. The watered appearance is usually created by the finishing technique called calendering. Moire effects are also achieved by certain weaves, such as varying the tension in the warp and weft of the weave, or by running the fabric through engraved copper rollers. Silk treated in this way is sometimes called watered silk.

Moire is produced from two distinctly different methods of finishing. Calendering produces the true moire, known as "moire antique" and "moire Anglaise," which is a purely physical phenomenon. In calendering, the fabric is folded lengthwise in half with the face side inward, and with the two selvedges running together side by side. To produce moire, ribbed rollers are used, and the ribs produce the watermark effect. The rollers polish the surface and make the fabric smoother and more lustrous. High temperatures and pressure are used as well, and the fabric is often damped before being run through the rollers. The end result is a peculiar luster resulting from the divergent reflection of the light rays on the material, a divergence brought about by compressing and flattening the warp and filling threads in places, thereby forming a surface which reflects light differently. The weft threads also are moved slightly.

Changeable moire is a term for fabric with a warp of one color and a weft of another, which gives different effects in different lights.

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