GB/T 4893.2-2020Test of surface coatings of furniture—Part 2: Determination of resistance to wet heat (English PDF)

1 Scope

This Part of GB/T 4893 specifies the method for determination of resistance to wet heat on furniture surface.

This Part is applicable to all cured surfaces of painted furniture, and tests conducted on the surface of unused furniture or test panels. This Part is not applicable to leather and textile surfaces.

2 Normative references

The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

GB/T 3190, Wrought aluminium and aluminium alloys - Chemical composition limits

GB/T 3505, Geometrical Product Specifications (GPS) - Surface texture: Profile method - Terms, definitions and surface texture parameters

GB/T 10610, Geometrical product specifications(GPS) - Surface texture:

Profile method - Rules and procedures for the assessment of surface texture

JB/T 9262, Liquid-in-glass industrial thermometers and laboratorial thermometers

JB/T 9263.4, The types and fundamental sizes of solid-stem common thermometers

3 Terms and definitions

For the purposes of this document, the following terms and definitions apply.

6 Reagents and materials

7 Instruments and equipment

9 Test steps

9.3 Before the test, use a cleaning cloth (see 6.1) to wipe the test surface gently.

9.4 Use an oven (see 7.3) to heat the heat source block (see 7.2) to at least 10°C higher than the specified test temperature. The test temperature shall be selected from the following temperatures according to the test requirements:

55°C, 70°C, 85°C, 100°C. Then transfer the heat source block to the insulation pad (see 6.4).

9.5 Insert a thermometer (see 7.1) or other temperature measuring equipment into the center hole of the heat source block. If the temperature is lower than the specified test temperature, the heat source block shall be placed in the oven again until it reaches 10°C higher than the specified test temperature.

9.6 Place the white polyamide fiber cloth (see 6.2) in the center of the test surface. Spray (2±0.2) mL of distilled water or deionized water evenly on the cloth surface (see 6.3). Make it cover the entire area of the white polyamide fiber cloth.

NOTE: It is advisable to use a scaled dropper for spraying.

9.7 When the temperature of the heat source block reaches the specified test temperature ±1°C, immediately place the heat source block in the center of the white polyamide fiber cloth.

9.8 After placing for 20min, remove the heat source block.

9.9 When the test surface has cooled, use a cleaning cloth to dry the test surface.

9.10 Record the location and temperature of each test surface.

9.11 Place the test surface for 16h~24h without interference.

9.12 Use a cleaning cloth to wipe each test surface. Under the light source condition, carefully check the damage of each test surface, such as fading, tarnishing and discoloration, blistering, swelling and other defects. For this purpose, the surface is illuminated with a diffuse light source (see 7.4) from different angles, including angle combination, to reflect light from the test surface to the observer's eyes. The observation distance shall be 0.25m~1.0m.

Changes caused by the test shall also be determined by touching the surface. […]