PSA D27 1327 Paint Coatings - Resistance to Water Immersion (Ford Tank)

The “PSA D27 1327 Paint Coatings - Resistance to Immersion (Ford Tank)” standard, developed by the French automobile company Renault, describes a procedure for measuring the resistance of a paint film to immersion in deionized water.

In this procedure, in principle, the bubble density and the residual adhesion of the coating after immersion in deionized water at 40 degrees are determined according to the test method described in the standard “PSA D25 1075 Paint coatings - Cross hatch test”.

Equipment and reagents used in these tests include:

• Rigid polyvinyl chloride tank: Must be equipped with a lid and thermoregulation mechanism.
• Gradual thermometer: 0 to 100 degrees, with a tolerance of 0,5 degrees.
• Wiping tools: It should be a soft, lint-free cloth or absorbent paper.
• Deionized water: Resistivity should be greater than or equal to 200.000 Ω/cm (conductivity ≤ 5µS.cm).

Test samples or specimens should be representative of the scale to be characterized. To ensure this representation, it is necessary to find out the basic characteristics of the population under study. Selection criteria for test samples or specimens should be stated in the test report in accordance with the PSA A10 0156 standard. In case of doubt about the sampling, the PSA service should be contacted to obtain the guidelines to be followed.

When preparing test plates or pieces, the graded surface of the panels or pieces coated with the products to be tested should be approximately 1 dm2 in size.

The test plates are conditioned at 23 degrees plus/minus 2 degrees and 50 percent plus/minus 5 percent relative humidity for the following period:

• 7 days in case of air drying or low temperature curing paints
• 24 hours in case of high temperature curing paints

The steps of the procedure to be applied are as follows:

• The tank is filled with deionized water (the level should re-cover the panels by approximately 3/4).
• The device is turned on and set to 40 degrees plus/minus 1 degree operating mode.
• The test panels are placed inside the tank and the lid is closed.
• After the immersion time prescribed in the guidance document, the test panels are examined.
• For testing, the test panels are quickly wiped with a soft cloth without rubbing.
• After staying for 23 hour in an environment of 2 degrees plus/minus 50 degrees temperature and 5 percent plus/minus 1 percent relative humidity, the degree of swelling and color deviation is determined according to the indicators.
• Afterwards, the paint adhesion test is performed according to the test method described in the “PSA D25 1075 Paint coatings - Cross hatch test” standard.

Scoring for the degree of swelling is carried out using 27 photographs included in the annex to the standard “PSA D1571 16 Paint coatings - Swelling due to moisture” with the following classification:

• 0: Low distortion of F8 (only visible micro-bubble is allowed under a certain angle) or low chromatic aberration, which can be restored by light rubbing with cloth less than 6 hours after the end of the test.
• 1: F8 cut-off or irreversible color deviation, 6 hours after the end of the test.
• 2: M8 and F6 dimensions.
• 3: Other sizes and densities as above.
• 4: More significant distortion than D2.

Observation of chromatic aberration is carried out in the light box according to the PAS D15 5504 standard.

The expression of the result must take into account the rating and index of the photograph embodying the distortion.

A local distortion is not taken into account if the surface concerned is less than 5 percent of the total surface or if an incidental character (fingerprints) can be definitely detected. Chromatic deviation is not taken into account for any paint that does not have a visual function.

Grading of grip is carried out in accordance with the test method of the PAS D25 1075 standard.

Among the numerous tests, measurements, analyses and evaluation studies carried out for businesses in various sectors, our organization also provides testing services defined in the “PSA D27 1327 Paint coatings - Resistance to water immersion (Ford tank)” standard with its trained and expert staff and advanced technological equipment.