Cartridge pack wins award by shrinking

Stung by criticism that its ink-jet print cartridges were packaged to excess Hew-lett-Packard Co. recently embarked on an aggressive campaign to minimize the amount of packaging the cartridges require. For its efforts the Palo Alto CA firm won a 1994 Gold Star Award for Environmental Improvement in the Ameristar Packaging Competition sponsored by the Institute of Packaging Professionals. The project netted a 35% reduction in the weight of packaging required. It also yielded a 47% reduction in storage density illustrated nicely by the photo on p. 58 showing "before-and-after" pallet loads. And although source reduction was the main objective material cost savings of 35% was an added bonus. According to packaging manufacturing development engineer John Wilson the savings helped pay for design costs and necessary equipment. Perhaps the most notable change in the package was the use of flexible packaging in place of an aluminum tub with a heat-sealed foil lid. The backbone of this new flexible material is a 48-ga polyester reverse-printed by gravure in three or five colors that is extrusion laminated to a .00028" foil. The final layer is polyethylene for heat-seal purposes. Total thickness is in the range of 3.5 mils. General policy at H-P is to withhold names of suppliers so the name of the flexible film converter can't be provided here. H-P did however make an exception to its policy in the case of Doboy (New Richmond WI) the maker of the J-Series wrapper on which the lamination runs. Demanding standards "We have very strict package qualification tests including drop tests extended storage tests at elevated temperatures exposure to various altitudes and so on" says Wilson. "To pass those tests this package had to be especially robust and that represented a considerable challenge for Doboy and us. "The gussetted corners were very important because they allow us to produce a nice tight primary package that requires the smallest possible folding carton. Doboy was very helpful as we worked to get those gussets right. The stiff film didn't make it any easier and on top of that we wanted up to sixty packs a minute and high seal integrity." Without good seal integrity the ink in the cartridges can dry out. The seal must be long-lasting too because shelf life on these products is well over a year. Developed around the same time as the new materials was the necessary machinery beginning with an automated cartridge loading system nearly as sophisticated as the computer products that H-P is famous for. It was designed in-house. Upstream from it is a pick-and-place machine. It denests small polystyrene thermoforms in one of two configurations and places them on a conveyor. The thermoform then advances toward the automated cartridge loading system where cartridges are placed into the thermoform. A second pick-and-place unit then positions the top thermoform over the cartridge. Identical top and bottom "What's especially nice is that the top and bottom thermoforms are identical" says Wilson. "That means one part to buy and inventory instead of one top and one bottom." Although the color print cartridge is slightly larger than its black-ink cousin the outside dimensions of the thermoforms do not change. Instead subtle molding changes on the inside sidewall allow the two different-sized cartridges to fit snugly even though the outside dimensions of the thermoforms don't change at all. By maintaining these outside dimensions cartridge handling on downline equipment becomes considerably easier because it's consistent. Sandwiched by top and bottom thermoforms the print cartridge is conveyed to the Doboy wrapper. The infeed conveyor of the wrapper is perpendicular to the conveyor on which the cartridge travels. A pneumatically driven arm pushes the cartridge onto the infeed conveyor of the wrapper. The Doboy wrapper uses standard mechanical gussetting fingers that get an air assist from the outside to help create tucks smoothly and reliably. There's also a vacuum pulled inside the package that helps hold the gusset just before heat sealing occurs. Registration is necessary because the film is printed and this is accomplished by a sensor mounted just ahead of the forming plow that reads eye marks on the film and adjusts film feed accordingly. Once through the plow the material moves through three fin wheels. Two outer ones guide the film as the center one applies the heat that produces the fin seal. After the gussetting tools perform their task the sealing jaws close on the continuous tube of flexible material. This creates the trailing seal of the lead package and the leading seal of the following package. The cut-off tool separates the lead pack from the continuous tube of flexible material. At the discharge of the wrapping machine is a chute into which wrapped cartridges fall. At the bottom of the chute are empty pucks queued up on a conveyor that catch the cartridges coming through the chute. With a wrapped cartridge properly positioned in it each puck conveys forward to an automatic cartoner. Mounted on it is a pick-and-place unit that puts an instruction leaflet into each of the cartoner's buckets just before the cartridge is pushed in. A short distance later both leaflet and cartridge are pushed into a carton and the flaps are plowed closed and hot melt sealed. A date code is imprinted on the outside of the carton. Carton's greener too The carton now in use at H-P also got a little greener than its predecessor which was made of virgin board. Now the 16-pt paperboard carton is made of 100% recycled paper and at least 30% of its content is post-consumer material. It now has a header too with a better hang tab than previously. The old carton's hang tab was the kind that the retailers had to fold out away from the carton before it could be used and often the material would tear in the process. According to Wilson H-P's marketing managers are much happier with the redesigned carton not only for its hang tab but also its more prominent use of the company name. The carton is printed offset in up to five colors. As the carton exits the cartoner a checkweigher weighs each carton to make sure all components are inside. If anything's missing that carton is rejected automatically. Good cartons are conveyed ahead to a machine that flips every other carton so that the header of one meshes tightly with the body of the next one. In this orientation the cartons are automatically bundled in units of 10 and shrink-wrapped. Then ten bundles are loaded manually into a corrugated shipper that's taped closed and placed by hand on a pallet. Considering the many components and the complexity of the package being assembled the current speed of up to 60 cart-ridges/min is impressive. But Wilson says it should improve. "We're still going through some process evolvement and optimization" he adds. The new package has been available since October 1994 and is in use around the world. Bringing this sizeable project to completion was all the more rewarding because once all the design and development work was complete the in-store transition from old pack to new was accomplished in a very tight time frame. "That took a lot of planning" says Wilson. But he explains that it made it easier on the distribution system and it caused less confusion for customers because the amount of time during which they were exposed to the old and new packages side by side was minimal. The benefits of the new package are not only being experienced in the U.S. says Wilson. In Germany Green Dot costs have been reduced by 34% because the packaging materials themselves and the amount they weigh both score more favorably in the Duales System Deutschland Germany's packaging "take-back" system. Such savings are naturally welcome at H-P though the real significance of the new package is not a matter of dollars or Deutsch marks. It's a matter of pounds. As Wilson puts it "With this package we've eliminated hundreds of thousands of pounds from the waste stream each year."