There are some things to consider when washing garments containing TENCEL™ Lyocell compared to polyester/cotton blends. In consultation with your detergent supplier, a wash process should be developed to remove the soiling and staining considering the special requirements for fabrics containing TENCEL™ Lyocell fibers.
A) WHITE GARMENTS
Consult your detergent supplier:
In consultation with your detergent supplier, a wash process should be developed to remove the soiling and staining considering the special requirements for fabrics containing TENCEL™ Lyocell fibers. This should involve the use of a blend of anionic and non-ionic detergents.
Soap-based products should not be used, to avoid the formation of scums which cause greying of the
Brightening and stain removal:
Optical brightening agents can be used to enhance the whiteness if required. Either chlorine or oxygen-type bleaching agents can be used to remove stains; these must be completely removed from the garments (especially chlorine) before the garments are tunnel-finished, to avoid yellowing.
Rinsing:
There must be sufficient rinsing to remove all chemical residues from the fabric before tunnel finishing. The pH and alkalinity of the garments after rinsing should be checked, not only the rinse water.
Softeners:
If softeners are used, it must be remembered that excessive softener build-up can contribute to premature damage, like pilling formation or fiber hairiness on fabric surfaces, as well as in some cases causing a yellowing effect. This may affect propensity for soil catching.
B) COLORED GARMENTS
Brightening agents:
When washing colored garments, the use of optical brightening agents is not necessary. If used, they can give the impression of color loss because of their masking effect.
Bleaching agents:
The use of bleaching agents should be avoided except in exceptional cases as they can affect the colour and have the potential to damage the fabric if not fully removed during rinsing.
Bordeaux (401) and dark colors:
Bordeaux and dark colors are more susceptible to color bleeding. It is important to allow enough water in pre-washing and main wash to make sure that excess dyestuffs from the dyeing process are dissolved and washed out of the garments before wearing. If excess dyestuffs are still attached to the garment after laundering, it can increase the risk of color bleeding during wear.
It is recommended to pre-wash bordeaux and dark colors 2-3 times according to specified temperature in a single washing machine where loading capacity and liquor ratio can be adjusted.
Loading capacity: maximum 40%
Liqour ratio main wash: minimum 1:6
Liqour ratio rinsing: minimum 1:7
C) GENERAL
Lower loading capacity (appr. -20%) and corresponding higher liquor ratio compared to loading capacity of garments made in polyester/cotton blends.
Washing:
The washing process can be split into the following stages depending on the level of soiling:
- pre-treatment of the garment
- pre-wash – to remove solid matter so that detergents act on the soiling and staining effectively
- main wash –at a temperature maximum 75°C and a high liquor ratio / lower detergent concentration. pH after neutralization should be set between 6.4 and 7.6, please add adequate fresh water during the neutralization process.
- bleaching for white garments, should be done on low concentration (use other bleaching agents than hypochlorite to avoid cellulose degeneration)
- rinsing – Use of softeners is not recommended
Caution:
To avoid setting creases (thermal shock) when the wash load is being cooled down from temperatures of 50-60°C, the rate of cool-down should not exceed 2-3°C per minute.
It is recommended to have a sufficient rinsing process, when using bleaching and disinfection chemicals in the washing process, to avoid corrosion on metal trims e.g., buttons and zippers.
The hydro extraction of TENCEL™/polyester garments should not be excessive, otherwise creases can set in.
The extraction should be set to allow 30-40% water by weight to be left in the garments for optimum appearance after drying.
Drying:
The tumble-drying cycle (one dot) should include a cool down-period so that creasing is avoided. The residual moisture after drying should be 10-12%. If the garments are tunnel-finished, they should be fed into the tunnel finisher separately from other blends and finishes so that efficient drying and finishing takes place.
A fabric surface temperature of 120-130°C is adequate for good appearance. Bone-dry garments (garments where no water is left after washing) must not be tunnel-finished as this can cause problems such as shrinkage and scorching (change of surface color and texture due to heat).