Coating: Coating (涂层)
The application of a functional layer onto tape or teeth to improve water repellency, abrasion resistance or hand feel. Coatings may be sprayed, padded or roller applied, then cured. Coating weight and uniformity control performance and appearance; too much coating stiffens the zipper and blocks the slider, while too little leaves gaps. Adhesion, flexibility and resistance to washing are tested, and colour must remain consistent with the approved standard.