Inside Design: Colorful Plastics
The revamped FInesse shampoo bottle was colored by PolyOne, while the conditioner was done by Clairant. New techniques for coloring plastics are in the works, and the results look amazing.
By Marie Redding Senior EditorPearlized, frosty, iridescent, sparkling, neon, flashy, psychedelic...there now seems to be an endless number of colors for plastic bottles or containers. Different types of pigments and unusual additives can change a plastic's look even further. However, three important factors may dramatically alter your shade: resin type, percentage of recycled materials used, and molding method.
To achieve the right shade, seek the expertise of your color supplier and molder. Creating color should be a collaborative effort among everyone involved: the company's own design team, the supplier, the molder, and sometimes an outside creative design consultant. All are a part of the creative process and are influential in developing new looks, which is one of the moments when new trends in packaging begin.
Coloring PET
Polymer services company PolyOne (Bridgeport, CT) helped revamp Unilever's Finesse shampoo bottle last year, and the shampoo's new oval shape is now on shelves. Still its trademark blue, the bottle is more modern looking with a new deep, high-gloss finish. The package material was changed from a high-density polyethylene (HDPE) to a polyethylene terephthalate (PET) blow-molded bottle. Zalewski Designs helped develop the shade, but PolyOne was able to execute Unilever's vision.
"Colors look extremely vibrant on PET," says Unilever's senior design manager Laura Garza. "We couldn't have achieved the same look on HDPE."
Although PET resins can look fabulous, they're not without problems. Blow-molding stretches the resin and affects color distribution, so it may be hard for a colorant manufacturer to exactly hit a customer's target color without making a sample bottle first, to see how the color will look when stretched and molded. Color chips are the standard way to evaluate color samples for PET bottles, unless the company invests in an Aoki stretch blow-molding (SBM) machine as PolyOne did. Now, PolyOne can give customers sample bottles and take some of the guesswork out of providing the right color.
"We used to have a failure rate of 53% for color matching with PET resins. Now it's down to 4%," says Dan Martelli, marketing manager at PolyOne. The company has been developing colorant formulations for PET for the past three years, and there are only a handful of color manufacturers it competes with in the PET category. In comparison, there are hundreds of competitors that make other HDPE color concentrates.
Clariant's Splash-Swirl effect on a plastic closure. The Aoki machine may prove to be worth the effort and investment for PolyOne, since the amount of PET resins used in the world is expected to increase by approximately 5 billion pounds by the end of next year. This number was measured within a four-year time span, according to a study done by PET Packaging, Resin, & Recycling Ltd. The use of specialty propylene resin is projected to increase by only 1.3 billion pounds within the next four years, according to Plastics News and Phillip Townsend Associates.
Len Kulka, director of creative development at colorant manufacturer Clariant (Toronto), agrees that there is a PET trend emerging. He has a different method for achieving a customer's target shade.
"When coloring PET, the most important part of getting a match is evaluating the color effect on heat transfers," says Kulka. "I do this by being [on-site] during trial runs." Kulka says he can then evaluate when changes for color formulation are necessary and adjust the machines to get a perfect match.
Translucence
Unilever's design team decided to stay with HDPE for its new Finesse conditioner bottle, and it enlisted the help of Clariant.
"PET won't be right in every case. It depends on the brand's objective," explains Garza. The conditioner bottle, meant to be a softer contrast to the shampoo and also convey the product's benefits, is translucent with a baby-blue tint. The matching cap is also a soft blue.
Linda Carroll, market development manager at the color concentrate house Ampacet, says, "this year, we are seeing more earthy colors on the shelves that are glassy, lightly tinted, and translucent with an airy feeling." Carroll says more-subtle glitter effects are in. Allowing the product itself to show through the bottle has definitely been a big trend.
Frequently, caps and closures are custom colored to match the product itself when a bottle is translucent. Nancy Kane, marketing director at Zeller Plastik (Libertyville, IL), a division of Crown Cork & Seal, says the firm has been doing a lot of custom-colored closures, for brands such as Yardley and Avon's Naturals line of body washes and lotions.
Yardley's opaque white Body Wash bottle was changed to a clear one with a see-through label. Caps were color matched to each product in the line, which included a soft purple for English Lavender, a minty green for Aloe & Cucumber, a sand shade for Oatmeal & Almond, and a light yellow for Chamomile Essence.
Gem Tones
There is also an increased interest in opaque colors, especially for PET resins, which, not too long ago, were mainly used only in their clear state. "We will continue to see a growth in this color trend," predicts Clariant's Len Kulka.
Some of PolyOne's new deep colors for PET resins, called their Blue Planet Sequence. "Deep, rich, pearlescent tones work extremely well on PET because they show off the resin's naturally high-gloss surface," says PolyOne's Dan Martelli. He just patented 31 new special-effect color concentrates, which he calls Blue Planet Sequence, formulated for use with PET resins. They include rich reds, deep brownish merlots, dark blues, and vibrant greens.
"We've been very interested in deep jewel tones," says Gary Korba, vice president of creative packaging and innovation at Estée Lauder. "Colors that show depth and the technology to achieve this target are of high interest."
Next year, Carroll tells us, Ampacet is developing more "therapeutic colors" in shades of blue and green, while its new neutrals will have an ivory base. They will be named after gemstones, like Mystic Quartz.
Retro Influences
Reminiscent of the 1980s, when neon, paint-splattered clothes were in, and of the 1970s, with their mood rings, are Clariant's Splash-Swirl effects. They consist of random swirl and speckled patterns, and they can be used to make plastic closures, trims, or containers look like granite, marble, mother-of-pearl, wood grain, or tortoise shell. Glenroe Technologies, an orthodontic supply company, used Clariant's Splash formulation on retainer cases for children and teens.
Costly Color
Another trend is a move toward more high-end pigments, according to Clariant's Len Kulka.
"Exotic materials are very expensive, but people are willing to buy them," says Kulka, naming the most expensive as multicolorflip pigments, which are based on light refraction and look like different colors depending on the angle. Most colorants, including Clariant's pearlescent, metallic, and swirl effects, add less than 2 cents to the cost of the bottle. However, Clariant's new glistening StarMyst and Crystal effects, which use exclusive, limited-run pigments, add 525 cents per bottle
Clariant's new StarMyst and Crystal effects for plastic bottles. Kulka is a fan of multilayered bottles, not only for cost reduction, but also for visual effects. "Having only a thin, outer layer is not only cost-effective, but it intensifies the visual effect one-and-a-half times," says Kulka, "and you get dramatic results." Using high-end effects on multilayer bottles drops the cost by as much as 70%, since only the outer layer would require the expensive pigment. "We can make a plastic look like a metal. You can't get anything close to aluminum's reflectivity by using a single layer."
StarMyst and Crystal both sparkle, but Crystal also does a multicolor flip. In both effects, there is a large, oval-shaped pigment particle in the outer layer. "If you tried to do this in a single-layer bottle, the sparkle would get buried under all the other ingredients," says Kulka.
Clariant's business manager Carolyn Sedgwick explains, "There is a shift now from viewing color as a commodity toward viewing color as a marketing tool. Instead of thinking of color as just another expense, companies are using it in ways to help get their product off the shelf."
"The Crystal effect on a PET bottle is really interesting," Sedgwick continues. "Since the bottle itself looks like glass when it's clear, the color pigments end up looking like icicles—you could see large sparkles throughout the clear container. The color flip is very pronounced, and it's just beautiful." Clariant has been experimenting with this new effect in its lab, and we may see it on some of the most glistening products in 2003. *