Advancements in Pressure-sensitive Tape Technology Can Speed Assembly Operations in Multiple Industries

By Herb Bowling
Sr. Design & Application Engineer,
Avery Dennison Performance Tapes

 

Advanced acrylic adhesive technologies used in pressure-sensitive tapes are becoming the preferred bonding solution in an ever growing number of applications across diverse industries, replacing liquid and spray adhesives, mechanical fasteners and other bonding and fastening systems.  

The advanced technologies used in tapes have impressive assembly-related and performance characteristics, including the ability to withstand high temperatures, harsh environments and to bond securely with a host of different substrates and materials. They potentially allow managers of assembly and converting operations to lower the total cost of assembly and eliminate time-consuming procedures and cumbersome equipment.

 

Fast, Accurate Bonding

Easy handling and processing are major advantages of high-performance acrylic adhesive tapes. These pressure-sensitive tapes can help improve the speed and efficiency of assembly operations. They integrate smoothly into automated processes with in-line dispensing equipment and can also be applied by hand. Manual application requires only 8 to 10 lbs. of pressure.    

Unlike conventional adhesives, which tend to bleed at the edges, advanced acrylic adhesives used in pressure-sensitive tapes maintain their stability and integrity during processing. They facilitate clean, accurate tape placement and allow converters and assemblers to produce complex die cuts and diverse shapes. There is no need to drill or machine parts beforehand as required with mechanical fasteners.

With these high performing bonding solutions, assemblers and converters can often modify or eliminate outdated processes and equipment, improving the workplace environment. A recent case involved a parts assembler that had traditionally employed a spray adhesive bonding system. This required special application equipment and protective gear for workers. After switching to pressure-sensitive acrylic tapes, the assembler was able to speed up its bonding operation and eliminate the special spray equipment. Workers could do the job in regular clothing. 

 

No Curing Necessary

Hot-melt adhesives need to cool down after application, while conventional liquid adhesives require a curing period ranging from a few hours to an entire day. In contrast, high-performance pressure-sensitive acrylic tapes bond immediately and require no curing time, boosting the productivity of assembly operations.     

Some varieties of acrylic tapes can even be removed after application and repositioned—a benefit in hand-assembly operations. This potentially reduces the number of rejected parts. 

Pattern coating is an additional benefit. These pressure-sensitive tapes can be supplied with edges that are free of adhesive or with alternating adhesive and non adhesive tape sections. This can facilitate easier converting in assembly operations and cleaner handling by end users.     

 

Consumer Electronics Applications

The performance features of acrylic tapes, especially strong adhesion and low outgassing, make them ideal for various consumer electronics applications. The tapes can be produced in extremely thin dimensions to accommodate the space constraints of modern digital devices. 

Hard disk drives are a notable example. The high-performance acrylic tapes meet the application’s requirements for chemical cleanliness and can be accurately shaped to fit different drive configurations. The tapes help protect the disk drives from heat and vibration during use.  

Other consumer electronics applications include light blocking tapes for computer and device screens, optically clear tapes that limit distortion, and lens protection tapes to prevent damage from dirt and scratches. Also, thermally conductive acrylic tapes have been developed to transfer heat from LED lights and other heat sources to reduce operating temperatures.     

 

Automotive Uses

High-performance acrylic tapes also exhibit excellent high temperature characteristics and robust resistance to harsh substances and materials—properties that equip them for many automotive applications. The tapes perform reliably at continuous temperatures up to 400°F and intermittent temperatures up to 450°F. They also function well under load, such as when applied around corners.  

Low surface energy (LSE) materials such as polypropylene, polyethylene and other engineered plastics have proliferated in automotive applications, but they pose problems for conventional adhesives. High-performance acrylic tapes offer a better solution. They bond securely to LSE materials and can even be used to bond two LSE materials together.

In addition, these high-performance tapes absorb plasticizers without losing their special properties. Plasticizers found in many engineered films and foams cause rubber-based and other standard adhesives to break down and soften.

Automotive manufacturers are specifying advanced acrylic tapes in passenger compartment, exterior and underhood applications. They are being used, for example, for vehicle attachments, replacing mechanical fasteners and eliminating holes that can allow moisture or liquids to enter and be a starting point for rust. The tapes are used in tandem with damping materials or can be engineered to damp noise and vibrations produced by vehicle systems. The result is a quieter driving experience.          

In brake shim applications, high-performance acrylic tapes bond together two stiff materials, the metal shim and brake pad. Here, the adhesives can be stacked in such a way to dissipate vibrations at certain temperatures and prevent noises emanating from the brake assembly.      

Acrylic tapes that produce little or no volatile organic compounds find use in applications that require anti-fogging properties. They are earmarked for interior applications to improve air quality and prevent fogging on the windshield from the gradual release of volatile organic compounds.

 

Appliance Applications

Appliance applications also call for bonding solutions that can withstand high temperatures and resist damage from harsh substances. High-performance acrylic tapes are finding increased use, for example, in dishwashers, washing machines and dryers. They can securely attach sound damping foams and stiffeners in these appliances, reducing noise and vibration during use. They can replace mechanical fasteners in areas such as control panels, eliminating the need to drill holes in parts, speeding assembly.

Additional appliance applications include ovens, cook tops and microwaves. Here, high-performance, acrylic tapes are able to maintain adhesive strength despite exposure to vegetable oils, food acids and other harsh substances.

Advancements in adhesives used in pressure-sensitive tapes make it possible for easier assembly and higher bonding performance.

Originally published in Assembly Magazine.