Acrylic fibre | Serein Bangladesh
At one time the use of acrylic fibre offered the nearest approach in appearance and handle to wool carpets. Unfortunately the handling of acrylic carpets in piece form can be troublesome, owing to the thermoplastic nature of this fibre. Thus, after steaming, a gradual decrease in temperature rather than the ‘thermal shock’ of the conventional cold water wash-off is required. It may also be necessary to use special heat-finishing treatments to improve pile appearance.

Acrylic fibre

Modified basic dyes are employed for printing acrylic fibres and, although there is a wide range of products which give good fixation and fastness properties after steam fixation for 5–10 min, problems can arise in deep shades. The rate of fixation of modified basic dyes printed on acrylic fibre depends on their rate of diffusion into the fibre, which is not directly related to the Compatibility Values (CV or Beckman K factor) of the dyes. Thus although in batchwise dyeing applications CV 1.5 dyes exhaust more rapidly than CV 3 or 5 dyes, this is not the case in printing applications. It is, however, necessary to select dyes of similar CV to avoid incompatibility problems (colour variations within the carpet pile).

The rate of fixation is further affected by the degree of fibre saturation attained at any particular depth, which depends on the individual acrylic fibre and dye(s) used. Even with the best dyes, when printing on standard acrylic fibres, it is necessary to use a swelling agent to achieve optimum fixation levels in short steaming times. Various solvents are suitable for this purpose, including γ-butyrolactone, ethylene or propylene carbonate or chlorphenoxyethanol.
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Serein

Serein is an English-language documentary newspaper published in Dhaka, Bangladesh, founded in 2017.

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