(5) Pencil scratch resistance test of paint coating

This test is performed as follows.

1. The pencil lead is pointed at the painted surface at a 45 deg. angle, pushed at a constant speed for 10mm distance (consumed time of 2~4 seconds) with enough force not to break the lead. Repeat 5 times at different locations.
2. The pencil scratch resistance is defined with the lead hardness symbol used when 4 out 5 tests show no coating breakage.

(6) Boiling water resistance test of the combined coating

1. A beaker (1 liter) per one test specimen is prepared, and the test specimen is put in de-ionized water.
2. The beaker is kept at 95°C for 5 hours. The specimen is removed and examined to have no abnormality.

(7) Abrasion resistance of Combined coating

Abrasion resistance of compound coating is shown in [Table 3].

[Table 3] Abrasion resistance of compound coating (s)

(8) Accelerated weathering test of paint coating

This is an accelerated weathering test using a "Sunshine Carbon Arc Lamp" where the specimen is exposed to the light for 250 hours and its gloss retention rate is examined to determine the discoloration.
The gloss retention rate is derived with the following formula.

G＝G2×100/G1
G: Gloss retention rate %
G1: Specular gloss at 60° before the test
G2: Specular gloss at 60° after the test

(9) Naming of combined coatings

The combined coatings are named with symbols based on the Type, Anodizing film thickness, Paint coating thickness, and Quality classification.
The quality classification symbols are as follows. Boiling water resistance: Z, Sand drop abrasion resistance test: WF, Spray abrasion resistance test: WJ.

*Example 1: B-9・7-WJ

Type B, Anodize thickness 9μm, Paint thickness 7μm, Spray abrasion test of the coating ([Table 3])

*Example 2: P-6・15-WF

Type B, Anodize thickness 6μm, Paint thickness 15μm, Sand drop abrasion test of the coating ([Table 3])