form·al·de·hyde
a colorless, toxic, potentially carcinogenic, water-soluble gas, CH 2 O, having a suffocating odor, usually derived from methyl alcohol by oxidation: used chiefly in aqueous solution, as a disinfectant and preservative, and in the manufacture of various resins and plastics.
Fabrics are treated with urea-formaldehyde resins to give them all sorts of easy care properties such as:
Permanent press / durable press
Anti-cling, anti-static, anti-wrinkle, and anti-shrink (especially shrink proof wool)
Waterproofing and stain resistance (especially for suede and chamois)
Perspiration proof
Moth proof
Mildew resistant
Color-fast
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