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How to choose waterproof zippers

May 08,2024 BSL

Waterproof zippers should be selected from the following aspects:


1. The waterproof zipper film will not tear. No matter whether it is at a low temperature or repeated washing, the waterproof film is not easy to fall off or tear so the waterproof effect can be guaranteed for a long time.


2. Smoothness. It is generally believed that the smoother the zipper, the better the quality of the waterproof zipper. This is not the case. There are certain index requirements for the smoothness of waterproof zippers. Anything that meets this index requirement is a high-quality product. Of course, it is not To save costs, some businesses have reduced the material used in the code tape itself, which seems to be smooth to use, but it also greatly reduces the pull resistance and wear resistance of the waterproof zipper.


waterproof zippers


3. The surface of the waterproof zipper film is smooth and delicate, with a leather-like smooth feel. This is the appearance of a high-quality waterproof zipper.


4. The color difference of colored waterproof zippers should be small. The difference between the color of the zipper tape and the fabric is the color difference. The color difference between the color of the film surface and the color of the tape surface should be controlled within 5%.


5. In addition to color difference, you should also pay attention to the color fastness of waterproof zippers. Whether the color fastness of the zipper reaches the standard level and whether color migration occurs between the zipper and the clothing will directly affect the quality of the waterproof zipper product.


a. Color fastness mainly includes the washing and friction resistance of the product. It generally refers to the degree of fading of dyed fabrics under the action of external factors (extrusion, friction, soaping, rain, exposure, etc.) during use or processing. We should pay attention to the three color fastnesses of zippers: sun fastness, soap fastness, and color migration, to avoid the occurrence of these problems and improve the quality of waterproof zippers.


b. Sunlight fastness: Sweat stains occur with sun exposure. Therefore, the sun's fastness is not a single one, it includes dual fastness to sun and perspiration. Different degrees of sunlight will cause a series of photochemical reactions to destroy the structure of the dye itself, resulting in discoloration and fading. At the same time, the presence of sweat will make the pH value appear weakly acidic or weakly alkaline, which will also significantly reduce the sunlight fastness of some dispersed dyes. Therefore, this composite effect is very different from simple light fastness or perspiration fastness. The sun fastness of this composite can be enhanced by taking some precautions so that the color of the waterproof zipper remains bright for a long time. When choosing some zipper products, you should choose those that have been treated with UV resistance enhancement or directly choose waterproof zippers with high sun fastness.


c. Soaping fastness: The soaping fastness of the zipper tape is also an important indicator. For waterproof zippers, it is even more important. It is directly related to the waterproof effect of the waterproof zipper. General zipper tapes are woven from 100% polyester and dyed with dispersed dyes at high temperatures. The soaping fastness of dispersed dyes refers to the degree to which single-fiber or multi-fiber cloth will be stained by fading of the dyed material under certain washing conditions. Since dispersed dyes are dispersed inside the polyester, and the dispersion concentration of the dye gradually decreases from the surface layer of the fiber to the inner layer, more dye molecules accumulate in the surface layer. Therefore, the quality of soaping fastness depends on two aspects: first, the force between the dye itself and the fiber molecules. If the force is large, the dye molecules will be difficult to soap out of the fiber surface; second, the finishing process after dyeing, the residual amount of dye molecules on the surface of the fiber. If the post-processing is thorough, the residual amount of dye on the surface will be very small. Soaping will make it difficult for the waterproof zipper tape to fade.