Color management is an important aspect of polyurethane processing. More often than not, color is the key to making an attractive consumer product.
To give consumers a wide choice, polyurethane (PUR) products, for example, for automotive applications, sport and recreational products, are produced in a range of colors.
There is generally a trade-off in the form of increased manufacturing costs, because every color change takes time and reduces productivity. In addition, color changes often lead to color carryover, resulting in subsequent parts failing to meet quality criteria. The result is increased manufacturing costs due to the higher reject rate, higher material consumption and disposal costs.
KraussMaffei has developed a solution to these problems – the MicroDos color metering system. It’s especially cost-effective for polyurethane products that involve frequent color changes. To eliminate the risk of color carryover, all elements in contact with the pigment are integrated in the color-change module. For a color change, the whole module is simply swapped for a new color module. The MicroDos system makes color changes quick and easy and totally eliminates the risk of color carryover. The result is a more stable process and higher productivity.
MicroDos – KraussMaffei’s Modular Metering System
Changing a color module takes a matter of minutes so that the line is back in production very quickly. No traces of pigment are left in the metering system, so that no cleaning is required and no cleaning waste is generated. Fast, clean color changes mean more flexibility and a stable production process. Shown in Photo at right, the MicroDos system is engineered for high-precision color metering; the specified color concentration is accurately maintained, so that pigment consumption can be reduced to a minimum and product quality remains constantly high.
KraussMaffei’s MicroDos system can also be used for dispensing other polyurethane additives such as blowing agent, catalysts and stabilizers, which are usually added in low concentrations. Combining MicroDos with KraussMaffei’s multicomponent mixing heads can extend production flexibility even more, right through to color change from one shot to the next.