By Bob Lebeaux, President, The Plastics Group of America
December 7, 2009
Too often, management at molding facilities do not understand that unless you're trained in blending and/or color matching, it's not a simple procedure. If you're going to do it in-house, someone needs to learn the ropes, and, you also need to take a very close look at the alleged "savings" you're realizing by handling this function in-house – more often than not, you may discover that you're not really saving money at all. Here’s why: first, assuming that you have blenders, there's a significant cost associated with those pieces of equipment and their maintenance. Second, it costs you money to store and handle the color concentrates and additives. And third, it's a fact that many standard color concentrates lose their color intensity when added to a filled feedstock. This is called "bleaching," and it means that you need to increase the amount of color concentrate to try to achieve a color match. This costs more money and it also is dangerous; adding too much concentrate tends to degrade the physical properties of your resin.
Some resin compounders (including The Plastics Group of America) offer free color blending and matching as part of their regular compounding services. And the further upstream you can take the color blending process, the better the color match and consistency tends to be. The normal procedure is for the processor to provide their compounder with a color chip. The compounder then works with the color concentrate supplier directly to determine the proper ratios and blending methods. While it's true that some molders successfully do their own color blending and matching, my advice to you is to talk with your compounder about the options available. If they're willing and able to handle this function, and to do it for little or no additional cost, why would you want to do this yourself?