For designers, the consumers’ affinity for product differentiation is driving color customization in directions never before imagined. Until recently, the cost and logistics of mass color customization made it impractical from an OEM point of view. However, new technologies, such as AURA® infusion technology, are changing the equation, making mass customization a reality. In fact, the day may be coming when home appliances are custom-colored to match room décor, or other home appliances and electronics receive a custom splash of color to brighten kitchens, family rooms, bedrooms and every other place in the house.
After a short period of time, the parts are removed from the dye solution, rinsed with water to remove excess dye solution from the surface and finally dried to produce a market-ready product. Process cycle times are on the order of a few seconds to a few minutes. When the need arises to produce a part with a different color, the spent solution can be treated to recover both dye-free solvent and most of the unused dye, making the process very economical and environmentally friendly. The regenerated dye-free solvent can be used to clean process vessels and to formulate a new color solution.
The dyes penetrate the plastic surface to various degrees, depending on the softness of the plastic matrix. For example, for hard plastics like polycarbonate, the dye will penetrate the surface to a depth of 8-10 thousandths of an inch. For softer, more flexible plastics, like thermoplastic polyurethanes, the dye will penetrate through the article. However, regardless of the degree of penetration, the colorants in the finished articles cannot be rubbed off.
For white opaque articles that have been colored using color infusion, it is possible to etch the colored surface, exposing the underlying white substrate. This makes it practical for articles to be decoratively engraved by using a laser or CNC router to selectively remove the colorant from the surface. Corporate logos and other decorative patterns can be engraved in the article using these techniques. In addition to decorative engraving, different techniques can be employed to produce photochromic and gradient colors.
The dyes used in AURA infusion technology are typically Macrolex® dyes, the same dyes used when compounding polycarbonate precolored resins. These dyes have good inherent thermal and UV stability. For that reason, their performance in color-infused articles is similar to compounded resins in terms of weatherability as well as the harsh thermal treatment experienced by the material during the recycling process.
Process Control and Color Replication
The BaySnap system consists of two probes, associated electronics boxes and a computer. The dye-containing or dye-free solutions are contacted with the appropriate probe, and within several seconds, the relevant parameters are displayed, eliminating the time delay and costs associated with independent lab analyses. Using this analytical system, solvents and dyes (make-up) can be either manually or, more preferably, automatically added to the system using automated valves and reservoirs of fresh solvents.
AURA Infusion Technology: Improving
This technology makes it possible to color existing, natural-color parts. Therefore, AURA infusion technology can eliminate the need for the inventories and subsequent costs associated with employing precolored resins and masterbatch compounds. Just as important is the fact that any number of custom-colored articles can be made on demand, from one to a million and one. Consequently, article inventory and waste, resulting from production of an excess of custom-colored articles with molded-in color, is significantly reduced. In addition, cleanup of the molding machine and associated equipment used to produce articles from precolored resins and masterbatches is avoided.
The colors are customizable and the color infusion operation can typically be set-up in a molder’s shop, often alongside the molding operation. And as the required number of custom colors increases, AURA infusion technology becomes more cost effective than either pre-colored resin or masterbatches due to cleanup and missed-opportunity costs associated with the latter options.
AURA Infusion Technology Shows its Mettle
For instance, Bayer scientists discovered that AURA infusion technology can give a colored, metallic luster to plastic parts, an appearance that was almost impossible to achieve economically until now. Properly prepared, these parts render deeply colored metallic finishes, such as gold, brass, copper, silver, bronze, blue, green, violet, red and orange.
These metallic colors can be achieved in several different ways. For instance, a plastic part can be treated with either physical vapor deposition (PVD)or electroplating (EP) to produce a metallic layer on the plastic's surface. A clear coating is then applied to this metallic surface. The coating can be composed of almost any material as long as it is clear, adheres to the metal surface and absorbs dye from the infusion process. Certain polyurethane and acrylate coatings are particularly well suited for this application. The clearcoat is then colored with dyes using AURA infusion technology to produce the colored metallic finish.
Similar metallic finishes can be achieved using relatively flat parts laminated with metallized film. Metallized films are typically sandwich constructions. For example, to manufacture one such film, a clear polymer film such as polycarbonate is first vacuum metallized; then a second layer of clear polymer, typically polycarbonate, is laminated to the metallized surface to complete the sandwich. Using this method, the metal is the core layer. The desired colored, metallic finish is created by color infusing the polymeric surface of the laminate. The polymer film serves dual purposes – protecting the metal from tarnishing and absorbing the dyes from AURA infusion technology.
Metal surfaces, such as brightly polished aluminum wheels and large appliance doors can also be coated with a polymeric material, and subsequently, custom-colored with AURA infusion technology to produce bright, custom-colored metallic finishes. These surfaces can be produced very cost effectively. And, since the products are colored on demand, dead and slow product inventories are not occupying precious warehouse space.
Automotive ApplicationsBayer has utilized AURA infusion technology to produce aluminum wheels with metallic surfaces in gold, orange and red hues (Figure 4). This application is already garnering interest from automotive OEMs, and their interest is really just the tip of the iceberg. The time may be near that consumers can purchase aftermarket aluminum wheels and have them dyed to match the body color of their vehicle. But the possibilities for automotive color customization don’t end there.
But that’s just the beginning. Further down the road, it’s not hard to imagine vehicles with all-aluminum bodies being selectively treated with AURA infusion technology. Infusing exterior trim pieces, for example, would add a distinctive splash of color to high-end vehicles.
Other home electronics, such as televisions and computers, can also be treated with AURA infusion technology, enabling them to become an integral design element rather than just a functional – but drab – box. Furthermore, down the road, it may be possible to apply AURA infusion technology to plumbing and fixtures inside the house, as well as to outdoor brass or copper lighting fixtures.
Typically, with disruptive technologies such as AURA infusion technology, the infrastructure for bringing a product to market does not initially exist – it needs to be built. Bayer MaterialScience has selected a licensing strategy as the channel to market AURA infusion technology. Three diverse firms, each with a need to economically manufacture custom-color products, have already licensed the technology: Apollo Plating Inc. of Roseville, Mich., which specializes in nickel, chrome and zinc plating; Replex Plastics, a supplier of high-impact, high-performance optical domes and custom thermoformed plastic parts based in Mount Vernon, Ohio; and 3form, a Salt Lake City-based company that provides design-driven, environmentally responsible materials to the architecture and design markets.
Success breeds success, and as the full commercial power of AURA infusion technology is placed in the hands of the marketing savvy, the dream of mass-color customization will finally become reality. This will be much to the delight of consumers, and to the economic benefit of companies with the foresight to utilize this innovative technology.
For more information about AURA infusion technology contact John Skabardonis, firstname.lastname@example.org.