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Eastman Chemical Company .Corporate Headquarters .Kingsport. Tennessee 37662

EVOLUTION IN THE BULK-WATER MARKET RESULTS IN

THE CREATION OF 5-GALLON PET BOTTLES

According to the dictionary, evolution is defined as "the gradual development of something into a more complex or better form." A better form --- that's what we've witnessed in the evolution of the bulk-water market --- an improved packaging material.

In early history, water was stored in animal skins and large clay pots. Although storage was temporary and the water wasn't always pure and sanitary, the containers served a need. Water could be carried from its source to another location and kept for a few days.

However, over time, needs changed. Consumers began to demand pure drinking water,  which wasn't always available locally. Consequently, the bulk-water industry  was born.  Initially, water was bottled in glass containers that were sanitary as well as clear, allowing consumers to see the contents. However, they were also heavy and breakable.

As in all evolutionary  trends, the industry  began to look for a packaging material that would perform better than glass. The search led to polycarbonate. Bottles made from  polycarbonate were more durable than glass yet lighter.  Performance outweighed cost, hence the industry invested in new equipment and made the switch to polycarbonate.

Yet, the industry continued to evolve - to grow and develop. Today, the bulk-water market is growing rapidly, especially in Latin America. Bottlers resumed the search for a packaging material that was less expensive than polycarbonate and one that would perform better. They found what they needed in the single - serve water industry - PET, the material that has made the convenience water market take off.

Performance Criteria

PET may be the new kid on the block in the bulk-water industry, but it's outperforming polycarbonate. People who never considered PET for bulk-water containers are taking a closer look, and many are making the switch.  Five-gallon bottles made from PET weigh less than polycarbonate bottles, an important attribute with new OSHA ergonomic standards looming on the horizon. In the future, weight and ergonomic design will likely be the factors that affect the evolution of bulk-water containers.

Good Clarity

PET polymers are inherently colorless. Even if tinted blue, they provide excellent optics. They have excellent see-through clarity and low haze plus high brightness and sparkle.

One concern in the bulk-water market is scuff and abrasion resistance of the container. The high crystallinity of PET improves its scuff resistance. To test for abrasion, scientists

dropped 50 grams of sand on both PET and polycarbonate bottles. After measuring the increase in haze, the test was repeated using both 100 and 150 grams of sand. (Figure 1) Although haze developed in both types of bottles, it increased at a faster rate in the polycarbonate bottles.

Good Durability

The durability of PET has been a major concern for water companies. PET containers are oriented, which gives them good dimensional stability and good mechanical properties. They are very durable and have drop impact resistance comparable or superior to polycarbonate in both.the laboratory and actual use, even when stored outside and exposed to sunlight. When scientists exposed both PET and polycarbonate 5-gallon bottles to ultraviolet light over a period of time, the polycarbonate degraded more quickly and fractured more easily than PET (Figure 2).

In another test, the polycarbonate samples showed a much more dramatic color change than PET samples when exposed to prolonged ultraviolet light (Figure 3). Even with an ultra- violet absorber, polycarbonate yellows more quickly than PET over time.

Recently, a bottler tested the durability of both polycarbonate and PET 5-gallon water bottles by dropping filled bottles that were randomly pulled from the filling line. The bottles were dropped five times from a height of five feet. At the end of the test, 70 percent of the PET bottles were undamaged, while only 20 percent of the polycarbonate bottles remained intact (Figure 4).

A separate converter bottler conducted extensive ASTM distribution abuse tests on PET and polycarbonate 5-gallon bottles. They found that over half of the polycarbonate bottles developed leaks after only 30 minutes into an 18-hour test, which simulated the random vibrations and elevated temperatures that these bottles can expect to experience during real life truck delivery. There was no leak problem with the PET bottles during this simulated abuse due to their consistent injection-molded finishes.

Good Dimensional Stability During Washing and Storage

The bulk-water industry is also concerned about bottle shrinkage, particularly in PET. With its glass transition temperature of 79°C, it is true that PET bottles must be washed at slightly lower temperatures than bottles made from polycarbonate. However, the recommended wash temperature for PET is 60°C, which is 11 ° above the temperature required for sanitation. In a recent test, PET bulk-water bottles were washed 50 times in a commercial bottle-washing machine and shrinkage was measured at only 0.15 percent-less than one ounce, PET polymers are chemical resistant, and containers made from PET have fewer tendencies to stress-crack than polycarbonate, giving considerable latitude with respect to washing agents. Detergents such as poly (metasilicates), available under various brand names, can be used to wash 5-gallon PET containers. If caustic is preferred, the recommended concentration is 1-3 percent NaOH. Oakite (Oakite® 43-0M-150) and DiverseyLever (Divo® AHP) both offer detergents that have been shown to work well with PET at low wash temperatures. They also recommend chlorine sanitizers. (Oakite's Liquid Bactericide and DiverseyLever's Dibac) that can be used as room temperature rinses.

Bulk-water bottles are often stored outside for weeks at a time. Consequently, they are exposed to extremely high temperatures and shrinkage under these conditions is a concern, In a test by a bottle manufacturer, polycarbonate and PET bulk-water bottles were stored in a trailer for four weeks. At the end of that time, the volume in the polycarbonate bottles had decreased by 1.4 percent, while the volume in the PET bottles had diminished by only 0.5 percent (Figure 5).

No Off Flavor

PET polymer imparts no odor or off taste, meeting the strict taste standards of discriminating water companies, This attribute has been a driving force in the critical single- serve water market. As more and more consumers are assured of a clean, safe supply of drinking water from bulk containers, taste (or lack of it) will likely become increasingly important to them. In addition, PET polymers provide an excellent barrier to gases when compared to polycarbonate (Table 1). Therefore, the taste of pure spring water the bottler is endeavoring to capture (and the consumer is paying for) is maintained for long periods of time.

Benefits of Stretch Blow Molding and Resultant Design Features

Bulk-water containers made from PET are produced by stretch blow molding. Consequently, they have a superior injection-molded finish and the molding cycle produces consistent bottles time after time. Stretch blow molded containers are self-leveling, which results in more a uniform sidewall thickness than polycarbonate bottles which are formed by extrusion blow molding (Figure 6). There are no die lines, streaks, pigment tint variations or other surface imperfections to detract from the appearance of the container. Stretch blow molded containers have a superior finish integrity with a smooth internal neck and no pinch lines on the bottom surface. Leakage is virtually eliminated, a trait that is appreciated by both bottlers and consumers.

Bottles produced by stretch blow molding have a depression in the bottom surface of the bottle--a design feature that makes them easy to handle. Consumers handling the bottle grab the neck of the bottle with one hand and grip the bottom edge of the bottle with the other, using the depression as a natural handhold. Then they swing it up on their shoulder to carry. This inherent design advantage alleviates the need for a handled bottle, which is estimated to cost $0.75 more than a traditional bottle.

Economics

Lower Resin Costs

The cost of PET resin is significantly less than polycarbonate. By switching to PET, the bottle producer will also realize several other less obvious but equally important economies. PET polymers have a high modulus (Table 2), This means the sidewalls of containers made from PET can be thinner than sidewalls of containers made from polycarbonate. Because of its higher strength and modulus, less resin is used and the finished bottle will weigh less. Because of the "self-leveling" characteristics of stretch blow molded bottles, there will be uniform material distribution resulting in more efficient use of the material.

Blow Molding Efficiency

Although switching to PET does mean a major investment in equipment, the Nissei ASB- 650EXHD stretch blow molding machine produces two 5-gallon water containers per cycle in a 70-76 second cycle. Bottle production is more efficient, and there is no need for an annealing oven or trimming/finishing equipment. The combination of cheaper material, the need for less resin to produce a bottle, and the increased efficiency in production means a savings of $0.75- $1.00 per bottle. The bottler should recover capital costs in a relatively short time.

Fewer Customer Complaints

Since the finish integrity of PET stretch blow molded containers is smoother and more precise, there is a lower incidence of leakers while in use. This results in reduced cleanup costs for water suppliers. A customer in the southwest who has been using PET bottles for more than two years stated that he no longer needs to spend time and money cleaning carpets or replacing expensive hardwood floors because damage due to leaking water bottles has been virtually eliminated.

Under normal use, PET resists breaking. According to a customer who had 100 containers in a trial for more than a year, none failed. Another customer ordered approximately 15,000 PET containers. He reported his discard rate for new bottles (less than one year old) dropped from 1.1 percent for polycarbonate to 0.3 percent for PET bottles.

Environmentally Preferred

In today's environmentally conscious world, consumers and bottlers alike must consider the disposal of old bottles. Although polycarbonate is considered valuable as a potential recyclable material, it is not accepted at the vast majority of local municipal recycling facilities. PET is already a valued recycling material that is collected at every recycling center in the world.

The Future of PET in the Bulk -Water Bottle Industry

PET has a bright future in the bulk-water industry, especially with the introduction of EastapakAqua® polymer PJO03 produced by Eastman Chemical Company, the world's leading supplier of PET. PJO03 was developed especially for the bulk-water market. It has excellent clarity and low haze. In addition, PJO03 offers an improvement in cycle time over other PET polymers.

Eastman believes that PET represents the future of the bulk-water market. Customer perception and acceptance along with processing ease and durability will drive the switch from polycarbonate to PET. Eastman is working with water associations, bottlers, equipment makers and other suppliers to resolve all real or perceived problems and make the switch go smoothly.

As in any market, evolutionary trends will continue, but Eastman believes that PET will have a growing presence in the bulk-water market throughout the next millennium.

Eastman Chemical Company, headquartered in Kingsport, Tennessee, U.S.A., manufactures and markets plastics, chemicals and fibers worldwide with 1999 sales of US$4.59 billion. The quality systems of all Eastman® plastics are registered under ISO 9000 except at plants in operation less than one year.