UHMW products supplied with pressure sensitive tapes are subject to breakdown when in contact with contaminated surfaces. Therefore, proper surface preparation is the most critical element in the laminating operation.
A conscious effort on the part of the installer is required. The substrate should be as smooth and clean as possible. To prepare the substrate for bonding, wipe with a clean cloth. If oil or heavy contamination is present, you may need to use a totally evaporating solvent such as lacquer thinner. If only light soil and surface dust is present, an isopropyl wipe should be sufficient. Turn the cloth frequently to avoid recontaminating the surface.
Once the surface is clean and dry, apply the pressure sensitive system. Be careful when pulling off the release liner, refraining from skin contact with the adhesive. Skin contact could potentially reduce bond strength. It is recommended that, when applying long lengths, remove only 24″ to 36″ of liner at a time to make it easier to control. Once the product has been installed, a “J” roller or hand roller should be used to assure proper pressure and secure the bond.
It is recommended that the temperature be above 50℉ when applying pressure sensitive tapes.
When removing UHMW tapes, pry up one corner with a screwdriver or scraper and peel the plastic strip up using a pliers or vise grip. Remove residual adhesive with a clean rag and lacquer thinner or other permissible solvent. Do not use mineral spirits as it is oil-based and will leave a residual film.
If the adhesive backing was an Avery Dennison™ 8345 (rubber based), the adhesive will contain a .0005″ Mylar® carrier as a support. When removing the adhesive, you may need to scrape the residue to break through this carrier. The remaining adhesive can be removed by wiping with a rag and solvent. Make sure the surface is clean and dry before applying new UHMW.
1. Determine The Continuous Operating Temperature
While rubber adhesive systems are very versatile and aggressive, this is one area that rubber systems do not do well. Anything over 125F continuous will probably require an acrylic system.
2. Identify The Surface Energy Of The Substrate
It is the surface energy that determines whether a substrate is bondable or not. Teflon and polyethylene have very low surface energies and are difficult to bond. The surface of these materials will need some form of treatment to increase surface energy and enhance bondability.
3. Consider Whether The Adhesive Is Exposed To Concentrated Solvents
Some adhesive systems are very susceptible to solvent exposure and can break down the adhesive system. Solvent exposure will require an adhesive with cross-linking to withstand exposure to these chemicals.
4. Determine If Adhesive Is Exposed To Weathering
Excessive moisture and temperature variations can also wreck havoc on a pressure-sensitive adhesive. Knowing the varying temperature ranges will immediately determine if a rubber of acrylic is best suited. The ability to repel moisture or function in a high moisture environment will also narrow down your adhesive selection.
5. Determine If Adhesive Is Exposed To Direct UV Exposure
Outdoor exposure and UV will break down a rubber based system rather quickly. As a rule, acrylic adhesives are recommended for outdoor use. They provide excellent UV stability and temperature performance.
6. Identify Any Migrating Agents Exposed To Adhesive
Some substrates may contain plasticizers or agents that may migrate to the surface. These agents may interfere with the adhesives ability to latch on to the substrate and delamination may occur. In most cases a cross-linked acrylic will function well.
7. When In Doubt Give Us A Call
We know that it is difficult in many cases to be able to make a diagnosis on the spot. Don’t hesitate to call our Customer Service Department at 800-368-0238.