Acrylic is a heat-sensitive, thermoplastic fiber and is susceptible to stretching, especially when it is in a knit construction.
Acrylic can be found in many knit items, such as dresses, sweaters, skirts, and pants; as well as knit trims, including collars, cuffs, and/or waistbands.
Because acrylic fibers are not readily identifiable by sight or touch, drycleaners must rely on content labels to identify these fibers. Items that do not contain a content label should be handled as if they contain acrylic to prevent stretching.
The heat of the drying cycle can cause stretching in acrylic garments. For this reason, it is recommended that these garments be cleaned in a net bag on a short cleaning cycle and tumble dried at 120°F. Care must also be taken when finishing or steam pressing acrylic items. Always use light steam when finishing. The heat of heavy steam will cause the fabric to stretch. Acrylic items should be dried thoroughly with the vacuum before moving to the next lay. Touching the article while it is damp with steam may cause localized stretching. Items that are made with acrylic knit trims at the collar, cuffs, and/or waistband should not be finished on the steam-air form finisher. The expansion of the bag during the air cycle will cause the trim to stretch. If finishing is necessary, use light buck steam to soften fibers only and smooth gently.
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