Selecting the right tape
With such a wide array of adhesive materials on the market, selecting the right tape solution for your application can seem daunting
Understanding your substrate(s), or material(s), the types of bonds available to you, the load conditions, and environmental and cost factors will provide a view into the characteristics of the tape that will suit your needs.
How to choose the right adhesive tape
When choosing an adhesive material, you should consider a few criteria in order to achieve the desired performance. By understanding the end product and the conditions it will be subject to, a tape manufacturer is able to specify a material that will last the full life of your product.
- Materials and surface conditions
- Adhesives
- Stresses on the substrate and bond
- Environmental conditions
- Thin bonding
- Thick bonding
See more details on these conditions
How to incorporate tape into your product design
What to think about when choosing a tape or film for your product or application:
- Type(s) of substrate(s) bonded - Will the tape be placed on metal? Plastic? Cardboard? Would a certain thickness be more appropriate than another?
- Type and strength of adhesive formulated
- Nature of stresses on the substrate and bond (type of joint) - Does the tape need to be flexible?
Method of application - By hand or machine? Surface preparation (chemical cleaning, abrasion, degreasing, priming or simply wiping off dust)? Time ranging from immediate grip to achieving full bond strength (ranging from immediate to a few minutes to several hours)? Pressure ranging from firm hand or roller pressure to clamping over time to hold surfaces until reaching handling strength?- Ambient temperature and humidity of the work area.
Then, consider more than the cost per roll, taking into account:
Testing for a lower-cost solution for your design- The overall design and process cost benefits of incorporating tape into your product
- Your required minimum coverage
- All the properties of your substrate(s)
- Whether ventilation is required
- Your application equipment cost
- Your time and cost savings in alternative fastening processes
- The relative ease of use of adhesive tape.
Compare fixing and joining methods
How to use your adhesive tape
The way you use your adhesive tape is an important factor in achieving the desired performance of this component in your design.
Surface preparation
Whether using a manual or automated application process, the same principles apply:
For best results, surfaces must be clean, dry and grease-, oil- and lint-free. Substances such as dust, grease and wax must be removed before bonding. Typical cleaners include isopropyl alcohol (IPA), esters (such as ethyl acetate or acetone), and naphtha-based products.
Loose or flaking surfaces, such as those exhibiting rust, should be scoured with abrasive pads prior to fine cleaning. Surface roughness may also improve adhesion. Once the surface(s) has been abraded, they must be cleaned with an IPA-based cleaner, available both in liquid form and individual wipes.
Surfaces should also be cleaned where no abrasion has taken place, especially where heavy grease or oils are present. Clean surface(s) with a lint-free cloth and wipe in a single direction to ensure contaminants are completely removed and not smeared. In consultation with a tape manufacturer, use the recommended cleaning agents to ensure compatibility of the solvent with its substrate.
Pretreatment to optimise adhesive strength
Compatible substrates with a low surface energy (LSE) or porous qualities may need to be primed before tape application. These include Teflon, silicones and dielectric materials (such as polyethylene and polypropylene), which can be difficult to bond. Primer may also improve the durability of bonds to glass.
Compatibility tests
Depending on the substrate material(s), tests may be carried out to ensure that additives, such as plasticisers, do not interact with the adhesive used on high surface energy (HSE) or easy-to-stick-to surfaces. This would also be done in the case of non-ferrous metals (lead, cadmium, copper, brass and nickel) to ensure that a chemical reaction does not occur that could alter the surface polarity after contact with the adhesive.
Application
Usually, adhesive tapes require no more than finger or roller pressure to ensure bonding. Depending on your requirements, tapes can be integrated into an automated or manual assembly process. A tape manufacturer can advise you of the benefits, address your challenges and eliminate your concerns regarding the process(es) that would best fit your assembly needs.
Bonding should usually take place at a moderate temperature (about 20-22°C). In some cases, higher temperatures can decrease adhesive viscosity, accelerate adhesive flow and improve wetting, all leading to achieving full bond strength quicker. Bonding at very high temperatures, however, can cause stretching, and at very low temperatures can reduce adhesive contact (wetting out).
To ensure maximum initial adhesion, pressure should be applied evenly to the tape with fingers or a hand roller to accelerate adhesive flow, improve surface wetting and to eliminate trapped air. Adhesion builds with time. While adhesive tape bonds can normally be handled immediately, up to 72 hours may be required to reach final adhesion values (depending on the product and room temperature). Acrylic tapes, for example, usually achieve maximum adhesion only after 72 hours of dwell time.
In most cases, heat, water, solvents or any other pre-treatment methods are not necessary. Because of the high level of adhesive cross-linking, many tapes (including some fastening tapes) continue to build adhesion beyond the 72-hour timeframe and reach maximum adhesion after seven to 15 days.
Remove liners just before use, trying not to touch the exposed adhesive. Liner presentations can be designed to avoid this problem.
Storage
Adhesive tapes will retain their properties if properly stored:
- According to their shelf life, ranging from 3 months to 5 years, with the majority being 12-24 months
- At 20-22°C or the ideal temperature range for the product, protecting the tapes from freezing and high temperatures
- At 50% relative humidity
- Away from direct sources of UV (lights and sun)
- Rolls stored flat in a covered container or their original packaging
- Logs and spooled rolls should be stored to prevent distortion.
Most tape manufacturers and suppliers guarantee the quality and use of their products and provide product data sheets with recommended storage conditions.