Silica gel products will be the cause of the dark mark
Follow proofing engineer experience a handful of silicone proofing work, look at engineers perfect proofing, and own an all sorts of dark mark, so why I have to check with our engineers do silicone rubber products samples will appear dark mark?
A, color paste,
Poor heat resistance performance, the surface water of the silicone rubber products.
Prone to dark mark time molding rubber, its color is composed of two or more color paste mixing, a far cry from what if a few kinds of color paste heat resistance performance, this leads to forming at high temperature, some color paste did not change color, some color cream color because of poor heat resistance performance, patterns of the silicone rubber surface after molding, products have the waves caused by dark mark or obvious marks.
The solution in this case only color paste with better replacement and heat-resistant properties.
Second, the molding temperature too high or unreasonable discharging way can cause surface of silicone rubber products color is not consistent.
1, molding temperature more than color paste when the scope of heat-resistant, causing color cream color, form the dark mark, when there is dark mark caused by high temperature silicone rubber products, can be improve by reducing the forming temperature.
2, unreasonable discharging way can cause bad dark mark, usually characterized by rubber cutting too thick or too thin.
Solution: at the time of making rubber cutting specifications in addition to considering whether convenient exhaust, consider whether it will cause color silicone rubber surface after molding, products inconsistent three, different batches of rubber mixing together forming the surface color of the silicone rubber products.
The same formula of rubber, exists differentiation, such as color and hardness of different.
If you mix the two batches of rubber molding together, can appear the following situations: 1, the smaller products generally don't see two colors.
2, larger volume products are easy to see two colors.
Solution: preparation for material with one hand as a batch expect molding production, molding production will also be careful not to blend the two batches of material forming.
Bad appearance of the dark mark belongs to the surface of silica gel products, under normal circumstances is unacceptable adverse phenomenon, in addition to the individual silicone rubber accessories, such as silicone bracelet, silicone products, such as cases have mixed color when the design requirements.
Therefore, we are going to precautions according to the different situation, prevent dark mark situation appear.