GB/T 30789.4-2015

Paints and varnishes—Evaluation of degradation of coatings—Designation of quantity and size of defects ,and of intensity of uniform changes in appearance—Part 4: Assessment of degree of cracking

色漆和清漆 涂层老化的评价 缺陷的数量和大小以及外观均匀变化程度的标识 第4部分：开裂等级的评定