When a painted Slider is subjected to dry cleaning or a wet processing treatment, including washing a garment, the paint may chip off of the slider. The reason the paint chips off of a slider is because the slider is being damaged when it hits a tumbler during the processing.
Normally, paint will chip off of the protruded parts and edges of a slider. However, the degree of chip off may vary depending on the conditions of the treatment. Since the paint on the slider is a layer of coating, it is not durable enough to hold up when the slider is struck against an object. Therefore you should try to avoid scratching the painted parts of a zipper or allowing them to be struck against hard objects. Whenever paint chip off is a great concern, YKK recommends selecting plated sliders. However, please note that among the plated sliders, the X6 (Black Oxides) and V7 (Matte Black Silver) finishes are comparatively weaker and will not hold up against abrasion or wearing, and they may possibly exhibit a paint chip off problem when they are scraped or struck against hard objects.