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Testing procedures

Test specimen

The glass panel (about 150 mm × 70 mm × 2 mm) which is coated on both side is to be used as test specimen, unless otherwise specially specified. Four pieces of test panels are to be made according to coating method and drying condition designated by the manufacturer. The edges of three test specimens are to be duplicated with paraffin or wax, etc. at least 5 mm in width and one test panel is to be used for comparison. (refer to Fig 3.3.1)

Test method

(1) A glass bottle for one test panel is prepared as shown in Fig 3.4.1 and each bottle is filled with acid solutions (5 %, 7.5 %, 10 %) designated by the manufacturer up to 150 mm in depth and then maintained the temperature of solution at designated temperature. The test panel is to be hung by thread so that it may be immersed up to 120 mm as shown in Fig 3.4.1 and left it immersed for 480 hours. After 480 hours, the test panel is removed from the glass bottle and washed carefully with water and then drained off. The test panel is placed perpendicularly at room temperature for two hours and paint film is examined. In this case, edge of test panel and paint film within 10 mm in width from the immersion level are not examined.

Fig 3.4.1 Glass Bottle for Test (Unit : mm)

Kind

Testing procedures

Test method

(2) The inlet of the glass bottle is to be properly faced and the hole of glass plate is plugged with a cork. The test panel is hung with two strings of thread fixed to it and penetrated through the gap between the glass plate and the cork. So the height of the test panel is adjusted by the length of the thread fixed to it.

Acceptance criteria

Two test panels and over are to be examined with the test panel for comparison. In this case, paint film is to be free from cracks, blistering, peeling, pinholding, softening and elusion. There is to be no great change in color and gloss.