Colorants: heavy metals get the boot.

Eleven states now effectively ban cadmium- and lead-based pigments from packaging.

This spring, New Jersey became the 11th state to enact legislation based on a model proposed by the Coalition of North eastern Governors (CONEG), which will result in the beginning of a de facto elimination of heavy-metal-based pigments from plastic packaging applications. Depending on the state, the laws take effect between this past April 1 (Maine) and August 1, 1993 (Minnesota). Eight states--Connecticut, Iowa, Maine, Minnesota, New Hampshire, New Jersey, Rhode Island, and Vermont--ban all intentional introduction of lead, cadmium, mercury, or hexavalent chromium from incorporation in packaging sold in those states. New York, Washington and Wisconsin do permit those heavy metals to be intentionally incorporated in packaging, but only up to a total limit that declines in ensuing years from 600 ppm initially to 100 ppm by July 1995 at the latest. (A full report on CONEG regulations for heavy metals in plastic packaging has been compiled by the Society of the Plastics Industry in Washington, D.C.)

It looks like CONEG won't be the end of it. A bill in the U.S. House of Representatives would ban or restrict the use of lead in paint, packaging and other products nationwide.

HANDWRITING ON THE WALL 

Virtually all producers of pigments and color dispersions interviewed recently say they've long anticipated the results of the CONEG legislation and have adjusted their respective businesses accordingly. "Yes, this is a de facto trend. The handwriting is on the wall," says Jay Lindstrom, project manager for Reed Plastics. "During the last four years we've dedicated our research budget to replacing heavy-metal colorants and pigments."

Many producers of custom color dispersions, such as Accurate Color, Avecor, PMS Consolidated, Polycom Huntsman, Reed Plastics, and the USI Div. of Quantum Chemical, say they're constantly reformulating product lines to eliminate heavy metals--or have already eliminated some, like cadmium, entirely--driven by customer demand. Highly concentrated dispersions of organic-based pigments are in great demand, according to a PMS spokesman. Ampacet Corp. says over 75% of its new customer orders this year specify the need to comply with the CONEG legislation.

The ranks of heavy-metal pigment producers have been gradually shrinking--most recently, Ferro Corp.'s Color Div. announced that it will totally phase out heavy-metal pigment production within the next 12 months (see PT, March '92, p. 64).

The CONEG legislation merely accelerates what has been a gradual shift away from heavy-metal colors in recent years, according to a spokesman for Avecor. "Alternative organic pigments have been available for a long time; they just didn't fit the price structure for packaging. Organics are viable alternatives to heavy metals--but not equivalents. They cost more, have a different chemistry and there will be some compromises in performance."

STILL VIABLE IN DURABLES

Though there will be obvious short-term impact on heavy-metal pigments in the packaging sector, most colorant producers decline to write off these pigments in engineering or structural plastic applications. At best, several companies suggest there will be a gradual phasing out of heavy-metal pigments in certain applications, given the anticipated fallout of the CONEG legislation. But many say the cost/performance profile of heavy-metal pigments will remain highly competitive for the foreseeable future in high-performance engineering thermoplastic components used in durable goods.

"Lead and cadmium colorants are not a problem in certain durable applications," says Eric Reger, Ampacet's technical service manager. "Those colorant products will never completely disappear. Their property pluses will continue to make them a viable product."

Some colorant producers object to a certain degree of "hysteria and misperception" created by CONEG, making the case that many perfectly safe plastic applications utilizing heavy-metal pigments are being indiscriminately shot down by "overkill" governmental regulation. Even producers of organic pigments, who will benefit from the effects of the legislation, question some of the broad-brush judgments rendered by CONEG restrictions.

Stuart D. Swain, v.p. of Chroma Corp., says the CONEG legislation doesn't differentiate between soluble and non-soluble chemicals. "Cadmium is locked into the pigment; it doesn't migrate out," he says. "Legislators must be educated to the nontoxic forms of chemicals."

More New Products

Heavy-metal substitutes: Hoechst Celanese introduced three organic pigments designed to replace cadmium pigments. PV Fast-Yellow HGR and PV Red HG are orange shades, and PV Red HB is a blue shade. All reportedly feature high heat stability (620 F for the yellow, 600 F for the reds), and are said to be non-warping pigments.

New from Engelhard are non-metal-based pigments (naphthol red 2, 17, 22, 23) for printing on plastic packaging as well as coloring the packaging resin itself.

Fluorescents: Day-Glo Color has three new series of fluorescent pigments. VC Pigments for PVC are said to be formaldehyde-free and more economical than melamine-formaldehyde types, owing to their high color strength. STX Pigments for PVC organosols and plastisols are also formaldehyde-free and are said to combine solvent and chemical resistance with high color intensity. ZQ Pigments for polyolefin injection molding are said to be heat stable and to require low processing temperatures for maximum color development. Other benefits are reduced mold plateout, low dusting (because of large particle size), and ability to achieve high loadings in concentrates.

Harwick Chemical has a new line of Stan-Tone paste colors based on non-formaldehyde fluorescent pigments, for thermoset epoxy and polyurethane.

Other organics: BASF Corp. introduced two colorants--a perylene violet and a phthalocyanine red-shade blue.

Miles Inc.'s newest colorants include Palomar Blue B-4712 copper phthalocyanine pigment with high heat stability.

Dyes: New Macrolex Red H azo dye from Miles Inc. is formulated for PS and acrylics and reportedly resists sublimation during molding. Also, various Macrolex dyes now are offered in free-flowing, low-dusting versions.

Titanium dioxide: Kerr-McGee's new Tronox CR-837 is designed for use in high-temperature PE thin-film masterbatches. It has high tint strength and a blue undertone.

Ishihara Corp. USA has a new version of its Titaque product line in a free-flowing, ultra-fine particle size, one-tenth the size of standard Ti|O.sub.2~.

Hitox Corp. also has a new submicron buff grade, called Hitox 5. It's aimed at PP and PE thin films requiring opacity and high gloss. Also, recent improvements to standard 95%-rutile Hitox buff grade include lighter, more consistent color, SPC-controlled lower particle size, and neutral pH. Improved color allows use in a broader range of brighter, cleaner colors than before.

Pearlescents: Mearl Corp. is now offering Mearlin Card Gold and Card Silver, two new luster pigments developed specifically for credit cards and other plastic card applications. These bright metallic-like pigments are actually nonmetallic, nonreactive, nontoxic, nontarnishing, and nonarcing, the company says.

Other inorganics: Whittaker, Clark & Daniels recently introduced a free-flowing, low-dusting, surface-modified version of its DP Series ultramarine blue and violet.

Concentrates: Milliken Chemical recently introduced its "Advantage" line of non-nucleating opaque, organic colorants, available as a pellet concentrate. Designed for polyolefins, they reportedly provide a consistent rate of shrinkage over a wide range of custom colors.

Ampacet Corp. has come out with a new series of white concentrates, designated "T.S.T." Based on LDPE with 50-80% pigment, the new concentrates reportedly reduce die-lip buildup in high-speed, high-temperature cast film and extrusion coating lines. The result is said to be run times more than twice as long as with previous concentrates from Ampacet and other suppliers.

Liquid and paste dispersions: Harwick's new Stan-Tone liquid-color DIDP-based yellows and moly oranges are available in indoor and outdoor application series.

Morton International's new liquid "Speck" line, with speckled tones suspended in the colorant, provides a textured tone for styrenics and olefins. Also new is the "Commodity White" Ti|O.sub.2~ liquid color line, 10% lower in price than previous-generation colorants. The company also is in the developmental phase with a fluorescent line of liquid colors.