Masterbatch is a new type of polymer material colorant with superior coloring properties. However, there may be some problems in the use of color masterbatch. The following is a brief introduction to the reasons and solutions. :
1. In the sunlight, there are strips of pigmented paint in the product:
Considering both physical and mechanical properties of plastics and plastic molding processes:
The temperature of the injection molding equipment is not well controlled, and the color master cannot be thoroughly mixed with the resin after entering the mixing chamber;
The injection molding machine does not add a certain back pressure, and the mixing effect of the screw is not good;
The dispersibility of the color masterbatch is not good or the resin is not plasticized.
The process can be debugged as follows:
The temperature of the mixing chamber is slightly increased by the drop port portion;
Apply a certain back pressure to the injection molding machine.
If it is still not good after the above debugging, it may be the problem of dispersibility or matching of the color masterbatch and the resin.
2. After using a certain color masterbatch, the product appears to be easily broken:
The poor dispersibility caused by the poor quality of the selected dispersant or auxiliary agent affects the physical and mechanical properties of the product.
3. After using the ratio on the color master specification, the color is too dark/too light:
Although this problem is simple, there are many possibilities, specifically:
The color master has not been tried hard, and the pigment is too little or too much;
The measurement is inaccurate when used, and there are a large number of phenomena that domestic enterprises, especially small and medium-sized enterprises, measure at will;
There is a problem in the matching of the color masterbatch and the resin, which may be that the carrier of the masterbatch is improperly selected, or the manufacturer may arbitrarily change the resin type;
The temperature of the machine is not good, and the color master stays in the machine for too long.
Processing procedure: First check whether the resin type matches the color masterbatch, whether the metering is accurate, and then adjust the machine temperature or speed.
4, the same color masterbatch, resin and formula, why the color of the products injected by different injection molding machines?
This is often caused by the injection molding machine. Different injection molding machines have different mechanical conditions due to different manufacturing, use time or maintenance conditions, especially the difference in the degree of adhesion between the heating element and the barrel, so that the dispersion state of the color master in the barrel is also different.
5. Does the pigment migration phenomenon during the storage process affect the quality of the product?
Some color masterbats have a high pigment content (or dye), and in this case, migration is normal. Especially the color masterbatch with dye added, serious migration will occur. However, this does not affect the quality of the product, because after the color master is injected into the product, the pigment is in a normal color development concentration in the product.
6. After changing the resin of another brand, the same color masterbatch and formula, the color has changed, why?
Different grades of resin will have different density and melt index, so the properties of the resin will be different, and the compatibility with the masterbatch will be different, so that color change occurs. Generally speaking, as long as the density and melt index are not different. Large, then the difference in color will not be too large, you can correct the color by adjusting the amount of color masterbatch.
7. Why are some injection products not shiny?
There are several possibilities:
The dispersion of color masterbatch is not good;
Excessive titanium dioxide contained in the color masterbatch;
The molding cycle of the product is too long;
The nozzle temperature of the injection molding machine is too low;
The mold finish of the injection molding machine is not good.
8. After a period of time, some plastic products will fade:
The quality of the basic pigment is not good and drift occurs.
