- December 01, 1996, Bentley, David J., Jr.
The more parties that are involved in any project, the more opportunities there are for post-mortems that involve finger pointing if something goes wrong. This is especially true in our industry when a multicomponent construction that is intended for the packaging industry does not work properly.
The construction might be as simple as one flexible substrate laminated to another with an adhesive. It can also be considerably more complex, with inks, adhesives, primers, coatings, extruded resins, metallization, and a variety of substrates both treated and untreated.
The number of manufacturers involved in a construction tends to increase as the complexity of the construction increases. These manufacturers may include suppliers of resins, inks, films, adhesives, coatings, primers, and substrates. In addition, the people who do the extruding, metallizing, laminating, printing, etc., also contribute to the final construction.
When something goes wrong with the final product, whose fault is it? The ink supplier may point a finger at the laminator. The adhesive supplier may point a finger at a substrate supplier. Now you have a circle of people each pointing at someone else.
Sometimes the finger pointing can get downright vicious, because the cost of the unsatisfactory goods can be extremely expensive compared to the cost of any one component. Each person wants to blame somebody else to avoid the responsibility for the cost of the unsatisfactory finished product. Unfortunately the finger pointing usually does not provide any answers or solve the problem.
To do that, it is necessary for everyone to work together to find the fundamental cause of the problem. The best way to approach the matter is with the various tools of analytical chemistry. Gas chromatography and infrared spectrophotometry are probably the two most powerful techniques used to find the answers in this type of situation.
Gas chromatography can provide information on any volatile materials that may be in a suspect construction. It can therefore show the presence of any retained volatile materials or low-molecular-weight components. An indication of these in the faulty product could lead to suspicions about any material used that could contain such components.
The common use for IR spectroscopy in an unsatisfactory packaging material is to chemically identify the surface of a material. The first step is to delaminate the construction carefully to make the various surfaces available for analysis. Obviously one has to exercise caution during the delamination process not to alter the construction in any fashion.
Examination of a delaminated surface can show whether an ink, adhesive, primer, or coating has adhered where it should. IR spectroscopy can show the presence of any contaminating materials that might contribute to the problem. It can also tell whether there has been any chemical change in a surface or component of the construction.
Other analytical tools will occasionally provide information. One example is surface microscopy, which can often give useful data. A good analytical chemistry group can provide other useful tests specific to the elements involved in the unsatisfactory material.
While teamwork is essential in avoiding finger pointing when a problem shows up, the ideal situation is one in which teamwork, partnerships, and strategic alliances are part of the project from the beginning.
If all the suppliers and converters involved in a particular construction know the details of the job initially, there should be no opportunity for later problems. Every participant will have the opportunity beforehand to learn the compatibility of his or her product with all the other components of the construction and its suitability for the applications.
So, if you want to avoid product failure - and the finger pointing that often follows - make sure from the start that all of the parties involved in the job have the necessary information on the entire project. And if a problem occurs anyway, keep that team concept in mind when you search for the solutions.
David J. Bentley Jr. is a recognized industry expert in polymers, laminations, and coatings with more than 30 years of experience in R&D and technical service. Contact him at 505/299-6871.