Delustrant

A delustrant is a substance that reduces the lustre (sheen) of synthetic fibres. The most common delustrant is anatase titanium dioxide.

Synthetic fibres such as nylon are normally extremely shiny and transparent when extruded. Adding powdered titanium dioxide causes the surface of the fibres to be rougher, reducing the sheen, at the same time, being opaque, it reduces the transparency of the fibre. To be effective as a delustrant, titanium dioxide must be powdered 0.1-1.0µm, depending on the size of the fibre, and varying amounts (up to about 2%) can be used depending on the level of lustre required.

Usage in context: Viewing the white face of the cigarette filter with the naked eye and compression of the filter column with the fingers would suggest that the filter is made of a sponge-like material. However, opening the cigarette filter, by cutting it lengthwise with a razor, reveals that it consists of a fibrous mass. Spreading apart the matrix reveals some of the more than 12 000 white fibres. Microscopically, these fibres are Y shaped and contain the delustrant titanium dioxide. The fibres are made of cellulose acetate, a synthetic plastic-like substance used commonly for photographic films. Paragraph taken from: J L Pauly, A B Mepani, J D Lesses, K M Cummings, R J Streck. Cigarettes with defective filters marketed for 40 years: what Philip Morris never told smokers Tobacco Control 2002;11(Suppl I):i51–i61.

Some of the words used to describe different lustre levels are: clear, bright, semi-dull, semi-matt, dull, matt, extra dull, and super dull

References

• Dictionary.com definition of Delustrant
• textile.web.id definition of Delustrant
• Polymer modifications at University of Bolton