Milk fiber

Milk fiber or milk wool is a type of Azlon, a regenerated protein fiber based on the casein protein found in milk. There are several trade names for milk-casein-based fibers, including Lanital, Fibrolane and Aralac.

First produced and patented in Italy in 1935 by Antonio Ferretti^[1] and sold under the name Lanital, milk fiber was created under an Italian national self-sufficiency drive and was intended to capitalize on previous successes with rayon.^[2] Milk fibers enjoyed a brief period of success in the 1930s and 1940s. The popularity of milk fibers declined rapidly once full-synthetic fibers were developed. Fully synthetic fibers, such as acrylic, were able to significantly undercut milk fiber on price while being more durable.^[3] During the 2010s several producers tried to reintroduce milk fibers to commercial production.^{[citation needed]}

The production process of milk fiber was of some public interest and was documented on film by several contemporary sources.^[4] A simplified overview of the process is as follows:^[5]

1. Acid is mixed with milk to extract the casein.
2. Water is evaporated to form casein crystals.
3. The casein is hydrated to a thick syrup and extruded through spinnerets.
4. The resulting fiber is passed through a hardening bath.
5. The continuous fiber is then cut to the desired length.