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Colour transfer from handbags
Handbags are available in a vast selection of colours, which can lead to colour transfer problems.
Many bags are purchased for their aesthetic properties and to make a fashion statement, with little thought given to their performance. However, transfer of colour from these products can occur and, even if it does not lead to a return, it can lead to customer dissatisfaction. If a stained garment has to be dry-cleaned, this can result in a claim from the customer. It may be that the bag has also been placed on furniture and carpets, which could be permanently stained in severe cases.
To help ensure that handbags meet customer requirements, SATRA uses several different colour fastness tests along with guideline recommendations which, if met, should reduce the risk of colour transfer.
Many bags have shoulder straps that pose a high-risk of colour transfer. These straps will continuously rub against clothing, so if the clothing is white or pastel coloured, it will mark more easily. Even bags carried by hand will rub against clothing, albeit more lightly. Hands can also be discoloured through holding bags made from materials with a poor colour fastness. When checking handles and straps, any edge inking should also be tested as this can give rise to colour transfer problems.
Leather handbags can be made from soft, fine, full grain to heavily embossed corrected grains and also PU coated leathers. Generally, all of these have satisfactory colour fastness. However, suedes and nubucks are also used and these can be more prone to colour transfer problems.
Synthetic materials and textiles are also used extensively in bags, including synthetic suedes, PU coated fabrics, PVC coated fabrics and metallic finished coated fabrics.
Textiles come in a vast range of constructions, fibre types and colours. They can also be embellished with sequins and embroidery or have metallic yarns woven through them. All of these could result in colour transfer problems. When textiles are patterned using many different colours, it is essential that all of the colours are tested. Testing will confirm if the colours are fast or likely to bleed into each other. It is the unfinished leathers and textiles in deep colours, such as navy, red and green, that generally cause the most problems since they have to be heavily dyed to obtain the required colour intensity. However, black and lighter shades can also cause problems.
Colour fastness tests
Several tests can be applied for colour fastness to rubbing and, colour fastness to water and perspiration.
There are three different rubbing tests that can be carried out. These are:
- SATRA TM8:2004 – 'Colour fastness to circular rubbing'
- SATRA TM167:2017 – 'Colour fastness to rubbing – crockmeter test'
- SATRA TM173:2021 – 'Colour fastness to rubbing – reciprocating method'.
All of these tests can be performed under dry and wet (water) conditions and with a synthetic perspiration solution if required. Materials are rubbed with either natural coloured felt pads or a white cotton cloth. After testing, and drying out the wet or perspiration treated test specimens at room temperature, any staining that has occurred on the test pads or cloth is assessed against a Grey Scale (see table 1). This scale ranges from five to one, with five being classed as a good result and one being very poor. Half scale points can also be used.
|Table 1: Key to Grey Scale|
|Rating 5||No transfer of colour|
|Rating 4||Slight transfer of colour|
|Rating 3||Moderate transfer of colour|
|Rating 2||Marked transfer of colour|
|Rating 1||Very marked transfer of colour|
As well as rubbing tests, soaking tests can be performed. These are all contained in SATRA TM335:2018 – 'Colour fastness to water and perspiration' and test fastness to:
- water (Method 1)
- alkali (pH 8) and perspiration (Method 2)
- acid (pH 5.5) and perspiration (ethod 3).
In these three tests, the material is placed in contact with a multi-fibre fabric strip consisting of acetate, cotton, nylon, polyester, acrylic and wool fibres. The strip and material are then soaked in one of the liquids for a short period. The liquid is poured off and the combined materials are stored in an oven at 37°C for four hours. After drying at room temperature, any staining that has occurred on the multi-fibre strip is assessed using a Grey Scale.
Components used on the outer side of handbags, such as threads, zips, trims and beading can also be subjected to the same colour fastness tests, either individually or incorporated in test specimens cut from the main body material of handbags. The most appropriate rubbing test will depend on the size of the trim or beading.
For metal components such as buckles, trims and clasps, it would be sensible to measure their resistance to salt water corrosion (SATRA TM310:2020 – 'Atmospheric sulphide tarnishing and salt water corrosion' – Method 2). If these components corrode and rust, they could stain any white and light coloured clothing they come into contact with, not to mention the handbag material.
In SATRA TM310 Method 2, a sample of white cotton cloth is saturated with a sodium chloride (salt) solution. The metal component is then loosely wrapped in this and placed in a plastic bag, which is sealed while still inflated with air. This is left for 24 hours at room temperature and the component assessed for corrosion and the cotton cloth assessed for staining.
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SATRA can carry out a full range of colour fastness tests and predict performance in service. Please email email@example.com for further information or if you wish to have any handbags or leathergoods tested.