Over 600 delegates from 58 countries subscribed to the latest VDMA textile machinery webinar on sustainable dyeing held on February 3, 2022. The webinar, entitled ‘Resource-saving in textile processing – continuous dyeing and washing’, involved the 3 companies A. Monforts Textilmaschinen GmbH & Co. KG, Mönchengladbach/Germany, DyStar Singapore Pte. Ltd., Singapore, and Goller (HK) Ltd. Hong Kong/China.
The Econtrol is a continuous process for the dyeing of woven cellulosic fabrics that has already been well proven on the market on over 150 Monforts Thermex hotflue lines. Reactive dyestuffs are fixed into the fabric in a one-step dyeing and drying process with a controlled combination of steam and air. The entire pad-dry process takes just 2-3 mins at a temperature of between 120-130°C and a relative humidity volume of 25-30%. Compared to the common pad-dry-pad-steam process, no salt is used, and no steamer is required for a separate fixation step. No urea is used, and no smoke or deposits are generated. Furthermore, direct feedback of the dyeing results ensures no batching time is necessary and guarantees good reproducibility from the lab to bulk production. An immediate wash off is also unnecessary, allowing for flexible production planning.
Complementing the Monforts presentation during the webinar, Bertram Seuthe, Global Business Development Manager at DyStar, outlined the importance of specific Levafix/Remazol reactive dyes and Dianix disperse dyes for sustainable dyeing processes such as Econtrol, Cadira Continuous and CPB knit. In these processes, Sera auxiliaries are also employed for optimized wash-off results.
The latest developments of the Goller brand for the washing process can reduce water consumption by between 10 to 20%, as well as reductions in both heating energy and waste generation, depending on the specific fabric construction and required shade. The Goller Sintensa Cyclone has a unique washing mechanism which is not affected by the fabric speed. The concept is based on a programmable washing action – from low to very high – and on a washing effect independent of the fabric speed, with simultaneous gentle fabric transport. The continuously adjustable speed of the internal rotor on one hand causes an overpressure which presses the liquor through the transport drum and the fabric and on the other hand a vacuum which sucks the liquor through the fabric and transport drum. This interaction ensures a good and intensive flow of the washing liquor through the fabric on the drum and results in a very high washing effect, independent of the fabric speed.
The Goller Effecta module has been developed for a lower space requirement, as well as low liquor content to optimize the use of water. The washing process comprises 3 separate steps – surface cleaning, soaping and rinsing and neutralization with final rinse. During surface cleaning the main target is to remove the unfixed dyestuff from the fabric by high washing action. The Goller solution for this process is the Sintensa Cyclone, whereas the Effecta is employed in the other steps where more time is required to achieve the required result.