The process of nitrile coated gloves and common problems
Source:未知Author:Gloves Addtime:2018-07-31 14:14:27 Click:
In recent years, allergic events in natural latex coated gloves
have occurred frequently, mainly due to the presence of allergen proteins in natural latex. The current solution for safety glove industry is to manufacture safe latex products. The latter is ideal target. The most promising substitute for natural latex is the synthetic latex, namely nitrile latex. The nitrile dipped industrial gloves do not contain allergens and more comfortable and safe to wear. Its dial application areas are pharmaceutical industry, semiconductor industry and oil field. Nitrile glove is the ideal for more demanding work.
If the nitrile latex is to be vented after the completion of mixing, the mold used is not glazed. If the glazed mold film is used, the mold will shrink excessively. After the coagulant is dried, the temperature of mould does not exceed 70 ° C. The poor film formation will be resulted if temperature is higher than 70 ° C, and the film will begin to gel after immersion in the nitrile latex. The correct pH will ensure that this process is completed before leaching stage. The next problem is leaching glove, because nitrile latex is comparative stable, there is a large amount of surfactant in the wet gel. Leaching water will remove excess surfactant, remains in calcium chloride and soluble impurities. The leaching temperature can not exceed 45 ° C, film will shrink if above this temperature. The final stage on the production line is vulcanization. The nitrile latex does not have pre-vulcanization, so the vulcanization temperature should be high. In the vulcanization cycle, the temperature in the oven must exceed 110 °C. The optimum curing conditions should start from 80 °C-90 °C and then increase to 110°C-120 °C, finally reduce to 80 °C ~ 9O °, the insufficiently vulcanized nitrile material will emerge wrinkles, stickiness and damage durability. After demolding, semi-finished gloves will be chlorinated to remove surface viscosity.
The first problem is pinhole.
Reason: The nitrile rubber has hidden bubbles, impregnation is not suitable, the condensed condition is not appropriate and dispersion is not well dispersed.
Solution: The compounding time of nitrile material exceeds 16h, the temperature of hand mold should be not too high, the temperature of rubber material should be below 24°C, the hand mold should be clean, and coagulant should be filtered to ensure sufficient dispersion grinding time.
The second problem is flow marks and knife marks of nitrile
Reason: in the process of dreading, the nitrile material is not continuously fed in or out, and the gelation speed is not controlled properly, immersion temperature is not control appropriate.
Resolution: reduce jitter, control the amount of stabilizer and control impregnation temperature.