Compatibility Testing


After 25 years, I still get amazed with brands that do a quick aesthetics test, i.e. “does it look and feel like I want my brand to be perceived,” but then do little else. Product development is a high investment component for any brand that is looking for growth by releasing new or improved products. To go only one step towards checking off to make sure the package protects and functions how you want, really is negligent in the task.

Don’t get me wrong, we are here to support you!

As your packaging supplier, we will provide as much as we can in terms of expected compatibility, between materials and address dispensing needs, however the ownership is ultimately yours. We have designed a 5-step checklist that we work through with our clients so that there are no surprises and brings the packaging selection into line with good manufacturing practices.


The Aesthetic Test/Print Test

Everyone naturally conducts this test. Does it look and feel like what I want, am I happy with the colouring, texture, should it be heavier or be more premium, is the artwork correct, etc. If your package doesn’t pass this test, then it won’t be taken from the shelf or ordered online. Our team see what works both online and in store on a daily basis, we can pass on knowledge on the options open to you.

Following on from the aesthetics test is the print test. When direct printingonto packaging you should always make sure the print has adhered well to the substrate. The industry standard test is to use 3M tape that is applied to the printed surface and pulled away. If the print remains intact then it is what is industry acceptable.


Sealing Test

 Sounds basic, but it gets missed. To carry out this test adequately ensure that the packaging does not leak over time, in an upright or in an upside-down position. Make sure the package is airtight and does not evaporate.

Check the primary package and the closure with the actual capping or sealing process to be used when in production. If the capping is to be done with an automatic capper, test with the automatic capper and note the torque required on your machine. If capping manually, ensure the trials are carried out with hand capping.

If it is a tube that is being sealed, check that the tube filler has specified the actual amount of unvarnished space required for crimping/sealing so that the seal is structurally sound.

Think about how you intend to ship/freight the finished goods. Some products will not have a problem in cartons and on pallets, but when sent via post with insufficient protection or outer packaging, it can result in the cap opening in transit, therefore resulting in leakage.


Capacity Test

This test determines how much headspace or ullage is required for the product to be filled and used effectively, even allowing for different temperatures. For example, shampoo products predominantly foam when being filled and then require more space to allow for this in the package.

When packaging powders the product will fluff going into the container, too tight for space and your filler needs to fill at slower speeds resulting in higher machine time and labour per unit.

The dispenser matters, if it is a pump or a spray this will have a dip tube and the space this takes needs to be allowed for.

Finally check with your chemist or manufacturer and note the specific gravity and any production tolerance they need to work with. If you are filling grams the specific gravity is used to convert it to millilitres. Packaging is sold by liquid volume even for dry goods and creams.


Compatibility/Stability Test

We can’t stress this one enough, we see companies wanting to forgo this one to make a timeline, but it really is gambling with your brand. Different formulations will have different concentrations and ingredients that react differently in different temperatures or when exposed to oxygen or even the packaging itself. Some formulations, for example, with more or less of an active ingredient may discolour or panel the bottle or tube (i.e. Suck the walls in).

Your filler or chemist can help you carry out accelerated tests to ensure that the packaging that you have chosen doesn’t change the colour, consistency or functionality of the product. If there is some adverse reaction we need to look at alternatives, barriers or thicker wall sections.

 At Weltrade Packaging we have a lot of resources to help our customers carry out these tests. We would much rather work with you and make sure you don’t have surprises later than gamble on a she’ll be right attitude. Our team is ready to support your packaging journey, we look forward to speaking soon.