One. Double injection advantages:
Mold can be two different color characteristics of the resin and color, into a single color products, molded products can be reduced group legislature and post-processing projects. Save the cost of printing dissolved, increase the aesthetic visual effects products to enhance the quality and value-added products. Not only have non-slip, increasing the friction function, flexible resin material to make it more ergonomic feel better. Two-color injection products of high quality stability, product deformation easy to control, high yield molding cycle is short, low loss than 7 percent of injection plastic bag, plastic bag manufacturing costs lower than the 20% -30%.
Two. Color forming principle
     Two-color injection molding usually refers to two colors or different type of plastic molding, two-color machine due to injection unit and the nozzle is handled separately, so the finished color is mostly clear color, no mixed together. Two-color injection molding machine with a general injection molding machine injection unit biggest difference is that machine activity template design. In general, two-color machine has two independent separate injection unit, generally only one set of injection molding machine injection unit. Two configurations of the two injection units with the manufacturers of the design in many forms, as the activity template design is rotating mechanism must be provided, such as increasing the general common design dial or shaft mechanism, so as to provide a 180 ° reciprocating rotation, so that the mold to produce cyclic alternating movement. Also some special color mode dial or its shaft mechanism is not required, but by mold or horizontal sliding alternately rotate.
Three, two-color injection molding products manufacturing process characteristics
1. Color injection molding machine consists of two structures, specifications identical to the plasticizing injection device components. Nozzle according to production needs to be its special structure, or can be rotated with the same structure of the transposition of two mold. When plasticizing injection, requires two sets of plasticizing injection device melt temperature, the same injection pressure, injection melt feeding amount and other process parameters, process parameters to minimize fluctuations in the difference between the two devices.
2. Two-color injection molded plastic as compared with conventional injection molding of plastic products, melt temperature and injection pressure during injection thereof have a higher parameter value. The main reason is two-color injection molding mold flow channel is relatively long, the structure is more complex, larger injection melt flow resistance.
3. Color injection molded plastic products to choose good thermal stability, low melt viscosity of raw materials, in order to avoid high melt temperature in the flow channel to stay longer and decomposition. Application of more plastic is polyolefin resins, polystyrene and ABS materials.
4. Two-color injection molding plastic products, in order to melt the material of two different colors can be well fused in the mold during molding to ensure the quality of injection molded articles, should be relatively high melt temperature, mold temperature higher , higher injection pressure and injection rate.
Fourth, the color in the form of the mold structure
The traditional two-color injection mold of "punch Pan" and "punch spin" two kinds of forms.
① "punch translation" of the mold has two die and a punch. When the first barrel of injection, the first punch and the die is closed. Completion of the first injection of a plastic.
After solidification of the first plastic, concave, convex die separately, forming a semi-finished product made of a first plastic stays in the punch, the punch and moves together with the second die to the alignment position.
After the injection molding machine is closed, the second cylinder for injecting a second plastic.
After the second plastic solidification, injection molding machine open mold, remove the complete article.
② "rotary punch" in the form of two-color mold die and by a combination of two back to back punch, the punch can be rotated.
 
     Both injection molding machine equipped with two cylinder, the second cylinder is preferably designed in the vertical direction of movement of the injection molding machine. Simultaneously injecting two different plastics. When the two kinds of plastic injection of coagulation, injection molding machines and automatic top opens a complete products.
After removing the products, "rotatable punch" turned 180 degrees.
Injection molding machine is closed, the next cycle.
    Since the first and second cylinder "Punches Pan" mode is injected in turn, and the first and second cylinder "rotary punch" mode are simultaneously injected. Therefore, the same product, with "punch spin" mode of production efficiency is to use "punch Pan" mode of production of two-fold.
Five, two-color mold new technology
     Color injection molding machine is equipped with two barrel. Mold is a single chamber, along with the first plastic ("PS") and a second plastic ("soft") needed a common cavity.
     The technology needed to die and a single punch, which is fundamentally different to the previous two modes of production.
When the first barrel finished the first plastic injection, plastic has a partially solidified rankings or solidified. Control since the beginning of the power cylinder to drive the blade isolation, retreated with punch-type surface level.
At this second injection of the second plastic barrel.
And so completely solidified after the second plastic injection molding machine open, and remove the complete article.
Then the injection molding machine shut down for the next cycle.
     Obvious advantage of this technology is to simplify the mold and reduces the need for the injection molding machine working space (you can use a smaller two-color injection molding machine in order to reduce investment and reduce energy consumption). And can exponentially increase production than the previous use of "plastic bag law" and avoid the bad products because of the shrinkage and deformation after "PS" again into the cavity produced radically.
     This technology can be widely used in color or multicolor (multi-material combinations) of plastic products. In particular
Car decoration plastic parts production, there is a great prospect.