A navy knit passes wash fastness comfortably. A few weeks later, the complaint arrives: the garment was left damp in a bag next to a white shirt, and the shirt is now blue at the contact points.
Washing did not cause that. Contact with water under light pressure, for hours, did — and that is exactly what ISO 105-E01 simulates.
What the test is
ISO 105-E01:2013 determines the resistance of the colour of textiles to immersion in water. The principle is simple: a specimen in contact with adjacent fabric is immersed in water, drained, and held between two plates under pressure in a test device, then dried and graded for colour change and staining.
The parameters, from the 2013 edition:
| Step | Requirement |
|---|---|
| Composite specimen | (40 ± 2) mm × (100 ± 2) mm, with a multifibre (ISO 105-F10) or two single-fibre adjacent fabrics |
| Water | Grade 3 water to ISO 3696 |
| Wetting | Approximate liquor ratio 50:1, 30 min at room temperature, pressed and moved occasionally |
| Removing excess | Wiped between two glass rods |
| Pressure | (12.5 ± 0.9) kPa between glass or acrylic plates |
| Incubation | 4 h at (37 ± 2) °C, device preheated |
| Drying | Hanging in air at no more than 60 °C, touching only at the stitching |
If that looks familiar, it should: the apparatus and the timetable are the same as the perspiration test, ISO 105-E04. Only the liquid differs.
Where E01 sits in the E-series
Labs sometimes run the wrong member of the family because the names are close.
| Part | Liquid | Typical concern |
|---|---|---|
| ISO 105-E01 | Water | Bleeding on contact when damp; storage and transport |
| ISO 105-E02 | Sea water | Beachwear, marine use |
| ISO 105-E03 | Chlorinated water (swimming pool) | Swimwear |
| ISO 105-E04 | Artificial perspiration, acid and alkaline | Garments worn against the skin |
The American counterpart of E01 is AATCC TM107. The ISO standard lists it only as a bibliographic reference; the two are not interchangeable, and a buyer's contract names one or the other.
Why dark shades that pass washing can fail here
In a wash test, loose dye is diluted into a large volume of liquor and partly carried away. In E01 there is no detergent and no flow. Whatever colour comes off the specimen has nowhere to go except into the adjacent fabric pressed against it for four hours.
That makes E01 a sensitive check for poorly washed-off unfixed dye. When the soaping or rinsing stage after dyeing is shortened, the effect can show up in water fastness before washing fastness moves.
Bench mistakes
The specimen dries out
The 2013 edition contains a short line that changes how the test should be run: specimens that show signs of drying should be discarded.
A composite that dries at its edges during the four hours is no longer in contact with water. Its staining result is lower than it should be, and the error favours the supplier. Causes are mundane: a device left near the oven fan, a stack with too few plates, an oven running hotter than 37 °C. Check every composite when you open the device. If the edges are dry, repeat.
Tap water or "distilled" from the canteen
The standard specifies grade 3 water. Tap water carries hardness, chlorine and variable pH, and all three can shift the shade of sensitive dyes. Use the same grade 3 water your lab uses for other ISO 105 tests and log its conductivity check.
Plates removed for small batches
As with E04, a test device takes up to ten specimens separated by plates, and all eleven plates must be used even when there are fewer specimens, to keep the nominal pressure correct.
Squeezing by hand
The method removes excess water between two glass rods. Hand-wringing leaves a different amount of water in every specimen, and the amount of water decides how much dye can migrate.
Grading the adjacent fabric against the wrong original
Staining is assessed against the original, unused adjacent fabric. Keep a strip from the same multifibre lot on the bench for comparison.
Yarn and loose fibre
For yarn or loose fibre, take a mass equal to about half the combined mass of the adjacent fabrics, place it between a multifibre and a non-dyeable fabric (or between the two single-fibre fabrics) and sew all four sides. Testing a loose bundle of yarn between unsewn fabrics lets the yarn shift and the contact area change.
Reporting
The report gives the grey scale rating (or instrumental assessment) for change in colour, the staining rating for each adjacent fabric or each multifibre stripe, the multifibre type, the option used and any deviation. "Water fastness 4" without a fibre name is incomplete.
E01 and E04 can share an oven and a day, but each belongs in its own device and on its own worksheet. A report that merges both results into one line leaves the reader to guess which grade belongs to which liquid — and that is where disputes begin.
Checklist
- Grade 3 water, fresh, with the conductivity check logged?
- 30 minutes at about 50:1, excess removed with glass rods?
- Eleven plates in the device, device preheated?
- Any composite showing signs of drying discarded and repeated?
- Staining reported per fibre?
TLI-TexLabInstruments manufactures the perspiration fastness tester used for this test in its own workshop in Istanbul.