New Clariant liquid color technology developed for polyolefin blow molding

New liquid vehicle technology (LVT) developed by Clariant Masterbatches appears to eliminate many of the problems that have prevented wider use of liquid color and additive concentrates in extrusion blow molding of polyolefins (high- and low-density polyethylene and polypropylene). Initial testing in monolayer containers shows that these highly compatible systems allow for higher pigment loadings and lower usage rates, while practically eliminating past challenges related to screw slippage. Improved resin compatibility results in stronger weld lines in the finished container as evidenced by scores in standard burst and compression-loading tests.

“Extrusion blow molders and brand owners in the personal care and household products markets often find liquid masterbatches to be an attractive alternative to solid concentrates,” says Raymond Sloan, Head of Liquid Color, Clariant Masterbatches North America. “However, until now, use of liquid color has been limited in blow molding of polyolefin resins because many liquid based carrier systems (including mineral oil) would not incorporate well with the resins. It was pigment friendly, but not resin friendly.”

The new Clariant masterbatches use a liquid vehicle system that incorporates suspension aids and binders have been incorporated into the new LVT masterbatches to allow for higher pigment loadings and (in most cases) lower usage rates. Additional components enhance flow and make for dramatically faster color changes. These and other advances allow Clariant to offer significant functional advantages in important applications and markets. Benefits include improved weld-line strength, better processing characteristics, faster color changes, and greater productivity. Testing has been completed in several types of monolayer containers and the company is confident that similar results can be achieved in multilayer applications involving both opaque color and pearlescent effects. Although liquids have had only limited acceptance in these markets, the company fully expects its new technology, along with Clariant’s industry leading technical service and global reach, to enable it to discover new opportunities in the extrusion blow molding market. Clariant is actively seeking processor partners to help us test and prove LVT benefits in specific applications.