How Does PDC Test My Product?
PDC’s shrink lab is equipped with a range of shrink tunnels for product testing. We stock many models and types of tunnels and do testing with sample containers and sleeves provided by the customer. As a service to our customers, we do product testing, mock-ups, determine material specifications and perform trial runs. Our technicians work with you to analyze your package and arrive at preliminary material specifications and optimal shrink tunnel configuration.
It is important to understand that the test results obtained from testing clear or lightly printed material will be different from fully printed labels with 100 or 200% ink coverage. Performing tests with the most analogous material samples on tunnels similar to those that will be used on line, will provide the best indication as to what can be expected in a production environment.
How Are PDC Shrink Tunnels Constructed?
PDC shrink tunnels are made of 18 and 20-gauge stainless steel and are built for high levels of cleanliness and sanitation. A secondary stainless steel outer skin protects operators from exposure to high temperatures.
In Hot Air and Radiant Tunnels internal baffles channel air flow over the elements and through chamber baffles, the design of which is varied to best suit your packages.
Standard tunnel voltages are 208/240 or 480 VAC, 3 phase. Tunnels are designed to pull up to existing conveyors and are suspended from above by a variety of tunnel stands. Conveyors, conveyor belts and wear strips must be made of materials appropriate for the temperatures generated, which can range from 200ºF in the tunnel to 600ºF at the elements.
Steam Tunnels have manifolds with valves that control steam flow in individual steam pipes which can also be adjusted to direct the steam as needed. Internal manifolds are made of either copper or stainless steel. Steam Filters clean steam to .1 micron and produce culinary grade steam.
What Are Pre-Shrink And Post-Shrink Systems?
For special applications, PDC has systems that help maintain control of the sleeve either during the initial phase of shrinking (Pre-Shrink Systems), or at the end of the process, after the shrink tunnels (Post-Shrink Systems) that finish off critical areas such as at the very base or top of the sleeve.
These units are self-contained industrial heat guns using nozzles to focus the heat. When necessary they are used in pairs. The utility sources for air and power can come through the application equipment. This way heat and air flow are monitored and controlled. The air flow is paused when the machine is waiting for product, reducing power to the elements and prolonging their life.
What Is A Shrink Curve? Material Types?
Since there is a range of available shrink materials that vary in type, cost and shrink characteristics, it is important that the company that is providing your shrink tunnels also specifies the correct type, grade, and material thickness, so that you get the results you and your customers expect.
In terms of percentage of market share, PVC is the most common and least expensive. Following, with much smaller market usage, are PETG and OPS, each with their own attributes, with OPS a relative newcomer to the US marketplace. Other new films are in development.
Resins from various companies are turned into sheet films by film suppliers who provide it to label converters, who then print, slit and seam the finished sleeve labels. PDC does R&D with the resin suppliers, film suppliers and label converters who work with PDC to test and develop the latest materials in the industry. PDC is considered a valuable resource for their work, as we can be for your product development and production, maximizing your efficiency.
Each type of base film has its own performance fingerprint or shrink curve, which is determined by the resin and other components, such as plasticizer, pigment, the type and amount of ink coverage – each sleeve has unique properties.
SHRINK CURVES chart the percentage of shrinking that occurs at specific temperatures over specific time periods when measured in a controlled environment. The path of the curve indicates at what temperature a material begins to shrink, the rate at which it shrinks, and when and at what point it reaches its maximum shrink percentage.
TRANSVERSE DIRECTION (TD) SHRINK – For example, there are “standard” materials which shrink up to about 55% in the transverse (horizontal) direction, high shrink materials that shrink up to about 70%, as well as special films – such as low temperature, freezer grade, and UV barrier films.
MACHINE DIRECTION (MD) SHRINK – Films also have some machine direction shrinkage (typically 3 – 7 %) which can cause sleeves to shorten in height – an effect that has to be controlled to insure acceptable results.
Can PDC Apply And Shrink Sleeve Labels Onto Our Products For Us?
Yes, PDC has Contract Sleeving Services that can provide you with sleeved products for:
- Internal testing
- Package development
- Consumer test markets
- Sales samples
- Production quantities (up to 1 million per year).
PDC can help you develop your concept, prove it out, and bring it to market. From concept to production, you’ll recieve PDC quality and commitment