Case studies: It’s all white29 April 2019
When you are faced with cleaning whites, Stacey King has some pointers on preventing them turning 50 shades of grey
Look on the bright side
Going grey is a worry you should save for your hair not your whites. Greying can be a major issue for the dry cleaner for a number of reasons. The causes of greying can be avoided by paying careful attention to machine/solvent maintenance, garment classification and detergent and programme selection.
Prior to processing it is important that garments are classified correctly and that a suitable detergent is used. Coloured garments should always be separated from whites and if possible, light and dark colours should be segregated as even the smallest amount of loose dye from the palest of items could result in discolouration. This is entirely manageable by the cleaner and is a quick and easy step, which should never be overlooked – prevention is certainly better than any cure. Poor preparation of the garment can also contribute to greying. Items that are damp (either through pre-treatment or natural humidity) can attract water-soluble soiling present in the solvent.
Use of poorly maintained solvent is also a contributor to greying of textiles. This can be either through poor distillation, poor filtration, or use of dirty working tank solvent. It is recommended that the solvent be checked before each use; it should resemble fresh water and should not have any drops of water present. If using perc drycleaning solvent these will be visible on the surface of the solvent whereas for hydrocarbon and GreenEarth they will sink to the bottom.
Working tank solvent used for the first bath should be sent to the still. It should not be assumed that the working tank solvent is suitable for use on whites and pastels. Programmes which use only pure distilled solvent are available and are recommended when working on whites. If the previous process contained large amounts of soluble contaminants (such as loose dye, or non-particulate oils/grease), these will be introduced during the pre-clean if working tank is used in the first bath.
Dirt, oil, and grime removed from dirty clothes in the second bath become suspended in the drycleaning solvent, which is then passed through the filter. If filters are not correctly maintained a build-up of detritus can cause the filter to burst resulting in particulate soiling depositing onto textiles and possibly being passed to the working tank solvent. Redeposition occurs when suspended soil is “re-deposited” onto the surface of garments. This can be reduced by the correct selection and dosage of an appropriate detergent, which will contain a suspending agent designed to prevent this.
Overall, whites should be not be feared. Stains on whites can be easily treated without fear of damaging dyes but take extreme care when handling items with contrasting panels or linings! This month we will look at some of the white items that DTC has encountered.
Fault: After drycleaning, the originally pale pink colour of the sheer fabric exhibited an overall grey discolouration. The pale grey flower detail appeared a darker grey as a result.
Cause: Ultimately poor classification of garments resulted in a dark item being cleaned with this pale pink dress. Loose dye from the dark item was dispersed in the solvent resulting in the even redeposition of migrant dye across lighter coloured garments.
Responsibility: A customer had requested an item be cleaned ‘urgently’ therefore the cleaner took a risk leaving them at fault for not correctly segregating items. The fault could have been avoided if like colours were cleaned together. The manufacturer would only be blamed where a garment had contrasting colours which are able to bleed into paler colours or where loss of non-fast dye results in a distinct colour fade.
Rectification: Greying which is a result of migrant dye pick-up is very difficult to rectify. If the garment was originally white, it is sometimes possible to restore the garment using either an oxidising or reducing bleach but this requires specialist chemicals and considerable skill. It is very unlikely that a coloured garment such as this will ever be restored to its original condition.
Dirty solvent = dirty items
Fault: The sofa cover was drycleaned on a delicate cycle in cyclosiloxane. When removed from the machine it exhibited an uneven dull grey appearance.
Cause: The sofa cover was drycleaned using working tank solvent. The solvent contained in the working tank was not clean enough for the garment in question. As a result, it has picked up colour to differing extents across the layers of the covers construction.
Responsibility: The cleaner here is to blame. Always ensure you check the working tank solvent is crystal clear and colour free before use on white garments.
Rectification: Re-cleaning with a high dose of an appropriate detergent may improve the appearance of the garment but it is unlikely the sofa cover will be perfectly restored to its original condition.
Moisture is a magnet for muck
Fault: Uneven greying was observed on a jacket, made from a wool blend, after cleaning. The area was localised to the lower right front panel.
Cause: The patchy area of greying was a result of insufficient airing time prior to cleaning. The jacket had a drinks spill on the right hand side resulting in the attraction of water soluble soiling to the affected area.
Responsibility: The cleaner should take responsibility for this. Be aware that wool can hold large amounts of moisture without feeling damp; sufficient airing is a necessity, not only to protect pale colours from greying but to minimise risk of felting shrinkage. Any trace of dampness will attract loose dye and soiling, which will become “locked in” to the fabric with strong electro-chemical bonds.
Rectification: Sparing use of a pre-treatment on the localised grey patches followed by re-cleaning with the maximum permitted dose of detergent might improve the appearance. The chances of success are dependent on how embedded the soiling has become.
Loose dye muddies the mixture
Fault: A skirt from a matching suit set was sent for cleaning separately to the jacket. Greying was seen after processing.
Cause: Greying was attributed to use of working tank solvent. The previous load was a dark load, this resulted in loose dye in the solvent which was then transferred to the working tank. It was this loose dye present in the working tank solvent which migrated to the whites in the next load.
Responsibility: The cleaner is responsible here as it should be checked that solvents are crystal clear and colour free before use. Particularly where light loads follow dark ones.
Rectification: Re-cleaning with an appropriate detergent might reduce the level of greying seen but it is unlikely the skirt will ever match the white jacket again. Using a special programme which only uses distilled solvent is advisable for whites and pastels, as is optimising detergent dosages.
Bursting out all over
Fault: The pastel blue curtain appeared grubby after cleaning.
Cause: When examined under magnification a multitude of stray fibres and dark particles, in all shapes and sizes, were observed on the curtain. This is caused by a filter burst which results in dirt and lint contaminating the load.
Responsibility: The blame here lies with the cleaner. Operators must watch the filter pressure and ensure filter maintenance is carried out regularly.
Rectification: Any loose fibres may be removed with a lint roller. For any embedded fibres, re-cleaning with a powerful detergent may help. Detergent suppliers will be able to advise a suitable option. The chances of success are not high and are dependent on how embedded the particulate matter has become.
‘Free’ dirt exacts a price
Fault: A blind was cleaned in a load where no detergent was used. As a result, the item appeared greyed.
Cause: Loose dirt and grime removed from other items became free in the solvent. The lack of detergent in this process meant that the ‘free’ dirt and grime redeposited onto all items in the load. This forms a layer only a few molecules thick on every fibre giving the overall grey appearance. Detergents contain surface active agents designed to trap soiling and prevent transfer onto clean items.
Responsibility: The cleaner is at fault here for skipping the detergent dose. Many cleaners do this either for cost cutting purposes or due to lack of knowledge. Drycleaning solvents do not prevent redeposition and should always be used in conjunction with an appropriate detergent.
Rectification: Re-cleaning with the maximum dose recommended by the supplier of a powerful detergent.
More haste, less speed
Fault: Patchy greying on a wedding dress after cleaning.
Cause: The dress had been submitted to the cleaner with a drinks stain. The cleaner flushed the stain with water to remove water soluble sugars and then pre-treated with a tannin remover. They subsequently failed to sufficiently feather dry the area of pre-treatment resulting in soiling being attracted to the damp area when cleaned in the machine.
Responsibility: Despite successfully removing the stain the cleaner should take responsibility here. Always ensure you make time to adequately dry any areas of pre-treatment prior to cleaning. Applying a layer of pre-brushing detergent over the damp area can also help to lift and ‘carry away’ moisture.
Rectification: A re-clean with a suitable detergent may improve the greying; ingrained soiling is unlikely to be removed on the mild process required for this delicate fabric.