Correct application of foamed acrylic tape: Expert advice
We discover why foamed acrylic tape can make your life easier.
The market for adhesive tapes is a well populated one, with a plethora of tapes to suit your needs. Choosing the best tape that would be effective for bonding substrates can be an issue which many sign makers can overlook, as there are many types of tapes, with different adhesive compounds.
Sign Update's new Editor, Ashwin Mehra spoke to Simon Dearing, Managing Director of Eurobond Adhesives who shares his expert advice on bonding and preparation techniques for foamed acrylic tapes.
What tips do you have for surface cleaning substrates before applying adhesive tapes?
Firstly, it is important to establish the type of surface you intend to bond to i.e. glass, plastic, painted metals etc. Glass substrates should always be cleaned with isopropyl alcohol and allowed to air dry. If practical gently warm the glass with an air gun for a few seconds to remove any surface moisture before applying acrylic tape. Powder coated or painted materials again should be cleaned with Isopropyl alcohol (IPA) to remove any surface grease or oils to prevent any contaminant being forced into the substrate material during the abrasion process. Then lightly abrade both surfaces to increase the surface area and clean again with IPA to remove any debris. Metals such as aluminium or mild steel may have protective plastic film coatings or light oil coatings. These need to be removed and the surfaces thoroughly cleaned prior to bonding.
How effective and economical are surface cleaner sachets and wipes compared to Isopropanol Alcohol (IPA) cleaning fluid?
With health and safety becoming more restrictive for many businesses, it is safer, more convenient and economical for businesses to use specially prepared cleaning wipes. Cleaning wipes packaged in sachets are fiddly and not really cost effective. However, by using wipes supplied in flip top tubs sign makers can build in the cost of a wipe to a particular process. Wipes will also improve quality control by ensuring fabricators use a controlled and standardised cleaning material that will not contaminate a surface by depositing lint or paper debris from dry cleaning cloths/tissues.
Why shouldn't sign makers use methylated spirits?
The use of methylated spirits and white spirits as cleaning agents is widespread throughout the industry. We have always recommended our customers NOT to use these liquids. These liquids leave a molecular trace on the surface which will act as an interlayer which interacts with the tape and causes it to degrade over time. Almost like clockwork you will see the bonded pieces start to fail at 90 days.
How do adhesive primers work?
Typically material surfaces can be classified as having low, medium or high surface energies. Low surface energy materials include plastics such as polypropylene, polyethylene, EVA and Teflon. These materials are very difficult to bond together and will require surface pre-treatment to change the surface energy to medium from high. This can be achieved in a number of ways: plasma treatment; Corona discharge; more commonly used method is the application of brush/spray-on surface primers. Primers are effectively volatile contact adhesives which when applied to a substrate, change its surface energy from low energy to either medium or high energy enabling tapes and liquid adhesives to bond to them much more readily.
What is the common reason why most foamed acrylic tapes fail?
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Failure is usually down to one of five reasons.
- Lack of knowledge by the tape salesperson wrongly specifying a tape for a given application
- Poor quality tapes
- Insufficient tape applied to surface area to support a given weight
- User error in selecting and applying the wrong tape for the given application
- Contamination either by the user or by the environment in which it is to operate in. i.e. ice, snow, rain, oils, detergents, heat, etc
What would you recommend the removal of adhesive tape strips from difficult sub surfaces such as plastics, vinyl and exterior window glass?
Foamed acrylic tapes can be difficult to remove from some substrates. However, little tricks of the trade include elongating the tape which helps to remove it from the surface. Special scrapers and the use of IPA wipes will also assist in the removal of tape.
What products would you recommend that would aid users in bonding?
Eurobond Adhesives Ltd supply rubber rollers to help 'wet out' the tape as it is applied to the surface, ensuring that there are no void areas and that the tape adheres to every nook and cranny of the substrate, however small. We also supply special low lint, IPA impregnated surface cleaning wipes. And of course we have a dedicated range of high performance tapes and structural adhesives for just about every conceivable sign making application.
- For more information telephone 01795 427888 or visit www.eurobond-adhesives.co.uk