Blowmolding growth comes from conversions


Freshco Ltd. recently introduced its Indian River juice line in clear 1-liter bottles, extrusion blowmolded by CKS Packaging using Eastman Chemical?s Eastar copolyester. That choice provided the desired water-clarity, high gloss, design flexibility, and allowed the economics of shorter runs. The resin can also be molded as handleware.


Making multilayer barrier containers at high volume, Wilmington?s Series III rotary blowmolding systems have outputs from 2500 to 3500 lb/hr, and can go up to 4500 lb/hr. Products range from single-serving juice bottles to 6-liter containers, with or without handles, and cavity count can be configured for a few thousand or more than 20,000 bottles per hour with any material or layer configuration. Wilmington will soon install a machine to make 30 million 1-gal polypropylene bottles/yr, and another for more than 80 million 1-qt bottles.


PVC slush molding has dominated the market for car interior skins for instrument panels and doors, followed by spray or slush processed PUR. Kautex Textron and Bayer MaterialScience have developed technology to blowmold a two-layer TPU) that can compete on price due to time-saving production and automation, plus it will not crack at low temperatures like PVC.


In launching its UMS 16D horizontal shuttle machine at K 2004, Uniloy Milacron says the system gives bottle makers tiebarless accessibility, in-machine trimming, and closed loop position and speed control for high precision. The UMS 16D provides two-, three-, four-, five-, or six-parison production in single- or double-station configuration. The unit?three by three cavities on 125-mm centers?features parison preblow and length control, pre-pinch, an electrically driven blow station, in-machine trimming, and oriented bottle transfer from both sides of the machine to one single-exit conveyor.


SIG?s Plasmax system puts a thin silicon dioxide coating on the inside of a PET bottle, boosting barrier properties as much as tenfold for still liquids and fourfold for carbonated soft drinks. It?s installed in Switzerland at Bina (shown) and in Japan at Hokkai Can, with more on the way, possibly in the USA in 2005. Thread-stop positioning to align caps on oval-shaped bottles such as are made on the SIG Blomax system is critical?and new bottle forms are multiplying.


At the K 2004 Show in Germany, Bekum?s BM-206/D will be running three-parison/six-cavity production of 200-ml milk bottles. Using Bekum?s tandem blow process?blowing from top and bottom?the output of a single- or twin-station system can be doubled. The process is said to be ideal for 100- to 300-ml single-serving bottles from one to six layers.


The IndexSB PET container system from Husky is being rolled out globally. The front-end injection system uses Husky?s Hylectric hybrid technology for high output and an index rotating cylinder with two sets of cores for overlapping cooling and molding. Preforms are mandrel-transported to the servodriven stretch blowmolding system via a conditioning station.


These auto fuel tank photos from Kautex Machines Inc. show the complexity of shape requirements conquered by the multilayer 3-D blowmolding process. The products require about a year of testing to ensure conformity to regulations before going to market.


The legend of the Master Thief, Ali Baba being one of the better known, exists in many of the world?s cultures. Blowmolders are likewise becoming masters at taking applications from glass, metal, paper, and converted packaging.

The blowmolding sector?which is actually many businesses?is doing well, and seeing even better prospects for 2005, thanks to thievery. Blowmolders shamelessly boast of poaching applications from metal, glass, paper, and converted packaging. Packaging for juice, coffee beans, mustard, motor oil, medicine, perfume, and dog food?you name it: blowmolders are swiping it.

More Containers of All Types

In June of this year the Freedonia Group (Cleveland, OH) released a market study called Plastic Containers. It says demand for plastic materials in containers of all types grew an average of 4.3% annually from 1998 through 2003. That represents 9919 million lb in 1998; 14,620 million lb in 2003.

In 2003, 77% of the resin went into bottles, and Freedonia says bottles will dominate the rest of this decade. The growth rate will decelerate as the soft drink and other segments mature, but improved heat resistance of materials should create other opportunities in hot-fill food packages. HDPE will remain the leading resin through 2008, but will be surpassed by PET by 2013, says Freedonia.

In what appears to be an odd twist, materials consumption for containers is expected to grow less rapidly than it has been, 3.6% on average for the next four years vs. the 4.3% of the past few years. Freedonia attributes that to ongoing efforts in lightweighting, thinwalling, and downgauging.

But how can you lightweight bottles and jars at the same time as designers are making the shapes more complex, as in the example of oval-shaped bottles and the oval caps that fit only one way? Oval shapes traditionally make it difficult to maintain uniform wall thickness. Providing sufficient moisture and oxygen barriers is also problematic, yet barrier properties are often the key factor in converting (or stealing) an application from, say, glass. And how do you keep the plastic bottle in the same dimensions and fill amount as the glass predecessor when the walls are thinner? These and other problems are all being solved with enhanced technology, and with no negative effect on the high production rates that are so critical in the container business.

For example, the Blomax Series III stretch blowmolding machines that SIG launched three years ago include preferential heating of the preform and mandrel support throughout the system. The former controls wall thickness so precisely that Peter Andrich of SIG Beverages North America (North Branch, NJ) says this problem has become a benefit. The wall thickness can be controlled so well that an oval shape can often be lightweighted with no loss of integrity; and 2 or 3g saved per bottle multiplied by 100 or 200 million bottles become tons of material saved in a year.

Similarly, the Series III provides 100% mandrel transport for the preform with no turning. Threads can be placed with a precision of ±1.5%, rather than ±10% that Andrich says has been the norm. He sees the trend to design differentiation accelerating, as well as a trend toward smaller package sizes for mobility and convenience.

Barrier Promotes Growth

Barrier enhancement, says Andrich, is a technology challenge for every segment other than still water, but the challenge is being met in many ways. SIG is heavily invested in its Plasmax silicon dioxide coating system, jointly developed with Schott HiCotec. A thin layer of silicon dioxide is applied to the inside of a PET bottle via PICVD (plasma impulse chemical vapor deposition). In effect, a thin layer of glass is present to block the passage of oxygen and carbon dioxide. The most often mentioned benefits vs. multilayer construction are that PET?s clarity is not diminished by the coating, and that the bottle is equally recyclable. The coating can increase the barrier level by a factor of 10 or more for still liquids, including hot fill, and by three or four times for carbonated soft drinks, says Andrich.

Andrich also says that the cost premium for plasma coating is ?insignificantly higher? to packagers who want clarity and recyclability. At a rate of 10,000 bottles per hour, the premium is about $15/thousand bottles, which should diminish to around $1/thousand bottles as the machines scale up. As it is a separate operation, there is no effect on yield rates and it can be used inline. There are no royalties. The first Plasmax installation in Switzerland is coating .4- to 1-liter PET bottles at a speed of 10,000 bottles per hour, and is integrated into an aseptic filling line. A second Plasmax system was installed at Hokkai Can (Tokyo), and a third system will go to Japan soon. Andrich says there is definite interest in North America, and the first system could be installed in 2005.

Jeff Newman of Wilmington Machinery (Wilmington, NC), an international supplier of high-output extrusion blowmolding systems, says his company?s business has been good across the last three years, and this year and next year also look good. He too cites material replacement as a strong, perhaps the strongest, force driving the growth, but he says barrier technology is the key enabling tool. For an example of how materials substitution and barrier properties combine to make things happen, look at the Folgers Coffee container now on supermarket shelves. Newman can?t say any more than that Wilmington systems are involved, but the application speaks for itself in terms of barrier and high volume?a combination that Newman says is becoming Wilmington?s lead card.

He notes that the containers primarily made of HDPE and PP on Wilmington?s large-wheel machines really don?t compete with PET for business; they compete with glass, metal, and paper, and increasingly they are winning. Obviously, PET is taking business where crystal clarity is wanted, but HDPE and PP are doing quite nicely with the rest, and they are right in the running for the growing number of hot-fill applications, too.

Newman agrees that designers are competing hard for shelf space, but not with the conclusion that design is an automatic advantage for PET. Clarity, he notes, is not an issue for many products, and the high-quality shrink labels going on multilayer bottles and jars make a nonissue of material appearance. Far more important is design-based function, such as when a bottler wants to eliminate the glugging effect when pouring orange juice and the supplier can reposition the neck to make it happen. Giving customers options has become more important to bottle makers, Newman says, which explains why virtually every new machine Wilmington ships has in-mold labeling (IML) capability. The molder may not be doing any IML at the time, but wants to be ready if a customer calls for it.

Most coextrusions are six-layer, Newman says, though there are a fair number of fives and sevens, and five is the usual number of extruders. He feels the lower cost of the olefin materials is a positive for future growth in extrusion blowmolding, which is enhanced by the ability to use regrind. PP and HDPE have been more price-stable than PET, and he expects them to stay that way. He adds that there are material improvements currently under development that will increase water and oxygen barriers.

Joe Spohr of Graham Machinery Group (York, PA) says the company has been doing very well in the general category of dairy products with its extrusion blowmolding systems. Graham?s reciprocating-screw technology is going over very well for milk bottles, he says, as are the systems developed for 5-gal PC water bottles. He says PET attempts to compete for milk containers, but HDPE is holding its ground, in part due to its price advantage, but also because clarity is not a big issue for milk. There are also issues related to food degradation from various light sources.

Material conversion is also a big driver for growth in Graham Machinery?s business across the board, says Spohr. Besides the more familiar glass and metal conversions, he is seeing a significant number of applications moving to blowmolded plastics from multimaterial converted packaging. For products such as ultrahigh-temperature processed, aseptically packaged milk, multilayer barrier is once again the key to moving to blowmolding. The blown products are six- or seven-layer configurations, mostly HDPE or in PP for many hot-fill applications, and EVOH for the barrier. The finished packages have far more shelf appeal than the converted ?bricks.? And Spohr notes that the ability to use regrind for cost reduction is a big factor.

There still is an overcapacity situation in the blowmolding sector, says Spohr, with utilization currently pushing up toward 80%. The magic number for action is usually about 85%, he says, and it is heading there steadily, even if not at warp speed. Also, some of that unused capacity is aged machinery that can?t meet the volume and quality needs in today?s market. He notes that America is still the biggest market volume-wise, followed by Europe, and Asia is rapidly gaining ground. A bit less than half of Graham Machinery?s sales are going outside the U.S. at the present time.

Preform and Container Together

Husky?s Craig Reynolds says the rollout of the company?s IndexSB one-step system for PET containers is proceeding as planned: Two are running in the U.S., two in Mexico, and another goes on stream in Europe before the end of 2004. Husky (Bolton, ON) wanted close control of the rollout following what Reynolds calls the most highly validated new machine development in the company?s history. The IndexSB in essence is a Husky Index preform injection system?a rotating turret with two sets of cores?married to a servodriven blowmolding machine. It will make containers from 25 ml to 5 liters.

The front-end injection is via Husky?s Hylectric hybrid technology, either with a reciprocating screw or as a two-stage system for higher throughput via continuous plasticating during the molding cycle. Reynolds says development is ongoing with this system; for instance a faster control processor is now serving the multiple servo actions, and the servodrives themselves have been upgraded.

Reynolds agrees that the blowmolding business is being spurred on by material changes, but it?s not a simple matter of substituting polymer for glass or paper. Product managers at marketing companies often want the same dimensions and contents in a PET bottle as they had in glass, and PET?s thinner walls mandate adjustments. Quite common is using a raised bottom similar to wine bottles, but it?s hard to blow material into the corners of a deep bottom plug. The IndexSB solves that by keeping the base plug down until the stretch rod can push the preform all the way down to the bottom of the mold. Then the bottom plug moves back against the push rod in what Husky calls delayed plug actuation.

In other developments, Husky is working to add heatset capability into the IndexSB, and the system also will have preferential conditioning to handle the oval bottles that are ever more in vogue. Reynolds says the system will fully support what he calls plastic?s greatest marketing benefit: freedom of shape design. He expects that the trend to new shapes will continue as marketers seek an iconic package, and as an example cites a water bottle that looks like a piece of ice. The IndexSB will also have thread-stop orientation shortly, probably during the third quarter of 2005, but sooner if a specific customer pushes for it.

The less visible industrial side of blowmolding is also seeing business improving. Wolfgang Meyer, president of Kautex Machines (North Branch, NJ), says his company?s backlog is healthy. It could be better, he says, but it?s getting there. On May 1, 2004, SIG completed the sale of Kautex to Adcuram, a German equity firm, thus completing SIG?s plan to divest itself of businesses outside liquid packaging. Meyer says that since then Kautex has gotten leaner to be more competitive, but is still supplying machines from its New Jersey base using U.S.-sourced components.

Meyer says legislation tightening evaporative emissions from small fuel tanks, such as boats and lawn mowers, is one factor having a positive effect on the industrial blowmolding business, even though the laws phase in during 2006 and 2007. Machines are already being discussed and specified to make the 6-layer tanks that will be needed and new plants are opening, many of them in the South. This activity is not as much in advance as it seems since the tanks need on the order of a year of testing to be sure they meet the regulations.

Generally, the multilayer blowmolding systems making fuel tanks use six extruders to maintain good wall thickness control. Fuel filler pipes, another good market that should be active in 2005, are currently being studied to see if they can be done with fewer than six layers, but blowmolding will almost certainly be the method for that application, too. Meyer also mentions the furniture industry as a potential source for future growth. Manufacturers are currently experimenting with 3-D blowmolding of structures with hard cores and soft outsides.

The 3-D business in North America has not benefited from the new auto diesel motor technology. Diesels are becoming dominant on European roads thanks to lower fuel prices and higher mileage, plus new engine technology that cuts pollution and improves performance.

The uniquely formed diesel intake pipes are practically all made by 3-D blowmolding. North America, says Meyer, continues to resist diesel engines in autos and is more likely go with hybrid cars in its quest for fuel economy. The activity in auto fuel tanks is stable, says Meyer, and is in line with auto sales. However, some new machines are being added by smaller suppliers, taking market share from others. About 65% of auto tanks now are in plastic, but the new Ford Futura and BMW?s smaller cars are using metal tanks. Concern about meeting emission levels is the force behind most of these decisions. However, blowmolded tank suppliers are able to put components inside the tank by leaving openings that are later welded shut. BMW uses that approach in its sporty Z4 roadster.

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