Evaluation of surface aging grade of wood coating for outdoor use

The surface of unfinished wood will age over time, dark wood will lighten, and light wood will darken. These color changes occur in different directions, exposure levels, and indoor and outdoor locations, so the changes are uneven and color aberration is prone to occur. Various colors may appear on one exterior wall.
Therefore, wood used outdoors usually needs surface treatment, and the evaluation of the surface aging grade of wood coating for outdoor use is very important.
Zhongke Testing Reliability Experiment Center has the capability of reliability testing of various painted surfaces, and provides professional aging grade evaluation services for outdoor wood painted surfaces.

Wood can be divided into:
according to how it is used 1) Wood restructured materials such as plywood, particleboard, fiberboard, laminated veneer lumber, laminated lumber, restructured wood, oriented strand board, restructured decorative veneer
2) Wood-based composite materials such as gypsum particleboard, cement particleboard, wood/plastic composite materials, wood/metal composite materials, wood conductive materials and wood ceramics.

1. The degree, quantity and size of coating aging damage are used to evaluate the aging grade of outdoor wood coating surfaces. It is represented by a numerical grade from 0 to 5. "0" means no damage or change, and "5" means serious damage or large degree of change. The four intermediate levels of 1, 2, 3, and 4 should be determined so that the entire grade range is optimally divided. If necessary, the intermediate half-levels can be used to record the observed damage phenomena in more detail.
2. It is usually expressed by "damage type: damage degree level or damage quantity level". For example, "Powdering: 2" means "the damage type is 'Powdering' and the degree of powdering is Level 2". When damage has a size level, it is expressed as "damage type: damage degree level or damage quantity level (S damage size level)". For example, "Blistering: 3 (S2)" means "the damage type is 'blistering', the number of blisters is level 3, and the size of the blisters is level 2."

GB/T 33568-2017 Surface aging grade and evaluation method of wood finishing for outdoor use
GB/T 250-2008 Textile Color Fastness Test Gray Sample Card
for Assessing Discoloration GB/T 4893.6-2013 Physical and chemical properties test of furniture surface paint film Part 6: Gloss determination method
GB/T 17657-2013 Test methods for physical and chemical properties of artificial panels and decorative artificial panels