In the production process, we often encounter that some waterproof fabrics are put in the factory warehouse or transported across the ocean and long-distance transportation to the destination. The waterproof effect is no or reduced a lot. This problem has always plagued the manufacturers.
According to a variety of experiments and tests, it is found that the causes of this problem are nothing more than the following:
1. The stereotype is not in place
Generally, it occurs on fabrics with a relatively high weight and a lot of liquid. Although the temperature setting of the setting machine can be set, the time required to evaporate the water needs to be longer. If the setting time is not extended, the waterproofing agent will not be able to form a film completely. It can form a film on the surface part, and it also has a certain waterproof effect, but after a period of time, the water contained in it and the unvolatile emulsifier interact with each other to soak the surface film again, so that the entire cloth surface is no longer waterproof. performance.
Solution: To solve this problem fundamentally, it must be fully dried and shaped in place; fabrics that have already had this problem can be repaired as long as they are shaped again.
2. Moisture rebirth of the hydrophilic group
Generally occurs in the processing technology of waterproof compounding other additives. The compound auxiliaries have a large number of hydrophilic groups. After the setting is finished, the waterproof agent has an effect and has good waterproof performance. However, after a long period of time, the hydrophilic groups of the compound auxiliaries will continue to return to moisture, and it will be waterproof in an ultra-humid environment. The blister fastness of the agent determines whether the waterproof effect is reduced. If the blister fastness is not good, it will be seriously reduced, and vice versa. To solve this problem, the compound additives must be selected first, and the water-repellent agent must be selected with better blister fastness.
3. The color fastness is not good
This situation generally occurs on polyester fabrics. The reason is that the low-temperature sublimation fastness of the fractional dyes used is not good. After long-term storage, the dyes migrate out and form a certain hydrophilic type. The solution is to control the fastness of the dyes well.