Have you ever wondered exactly how tape works? There are multiple types of adhesives on the market today. When you think of tape, you're most likely thinking of pressure sensitive adhesive tape.
What is pressure sensitive tape? And how do we use it? Keep reading to read all about pressure sensitive adhesive tape along with its benefits and common uses.
What is Pressure Sensitive Adhesive Tape?
Pressure sensitive adhesive tape is a strip of cloth, paper, metal, or plastic that has permanently tacky adhesive on one or both sides of it. The adhesive must be permanently stuck at room temperature and not necessarily heat activated.
It should be somewhat pressure activated, though, in that it sticks only if you put light pressure on it, with a finger for example. The adhesive should not change phases, meaning it should not go from a liquid to a solid. It usually comes on a roll.
Pressure sensitive adhesive differs from other adhesive tapes in that it only needs a small amount of pressure, if any, to work. Other types of tape may need water, solvent, or heat to activate the stickiness so the adhesive adheres to different types of materials like glass, wood, plastic, metal, or paper
Engineers are finding uses for pressure sensitive adhesives daily because of their sticky nature. They have load-bearing properties, which means that if the adhesive is strong enough, it can bear a significant amount of weight.
In the world of adhesive, you may hear specific terms that you need to know.
- Polymer refers to a large molecule with many atoms. The atoms are connected in a chainlike fashion.
- Viscoelasticity refers to when a material is both liquid and solid.
So, in short, pressure sensitive adhesive tape also referred to as PSA, self-adhesive, and self-stick adhesive is a polymer with viscoelasticity. The tape is sticky with a peel that protects the adhesive until you need it to bear weight.
Scientists, engineers, and everyday consumers find uses for PSA tapes every day. As adhesive technology increases and grows, people will find this type of tape even easier to use and less costly than traditional solutions for fastening.
Characteristics of Pressure Sensitive Adhesive Tape
To qualify as pressure sensitive adhesive tape, a tape must have three qualities.
1. Adhesion: this refers to the strength of the adhesive or the sticky material to the substrate, or the surface the tape sticks to.
2. Cohesion: refers to the strength of the adhesive or the strength of the stickiness.
3. Tack: refers to how long the adhesive takes to stick to a given substrate or surface. An extremely tacky tape would stick immediately with little pressure. A less tacky tape would take more pressure to stick.
Just to clarify, to qualify as a pressure sensitive adhesive, a tape must require pressure to bond. If it requires anything else like a solvent or heat, then the tape does not qualify as pressure sensitive adhesive tape.
Why Use Pressure Sensitive Tape?
Pressure sensitive tape is quick, efficient tape. It's becoming increasingly popular for a variety of reasons.
Pressure sensitive tapes are thin and light, making them easy to work with. Its thinness makes it easy enough for just about anyone to use.
Because pressure sensitive adhesive tape requires no other element other than pressure to activate it, it bonds materials quickly. Plus, it can bond materials that are dissimilar easily. You do not have to worry about if the materials are compatible.
Thus, when you use pressure sensitive adhesive tape, you can assemble a project quickly. You do not have to wait for the heat to activate the adhesion or a solvent to do its job. You just press on the tape, and it sticks.
When you use pressure sensitive adhesive tape, you can reduce the noise caused by vibrations. The tape will not rattle as a traditional fastener would. It absorbs noise.
Pressure sensitive adhesive tape ends up looking nicer. This type of tape reduces the need to refinish a surface. It also eliminates traditional visible mechanical fasteners. You no longer have a screw or fastener sticking up but a smooth finish instead.
PSA tape creates uniform thickness as well. it can fill gaps and create a more aesthetically pleasing product.
What is Pressure Sensitive Adhesive Tape Used For?
PSA tape is used for just about anything. You see it all around you if you look closely enough. Box-sealing tape or packing tape, masking tape, duct tape, double-sided tape, electrical tape, and even athletic tape like what you see on hockey sticks and baseball bats all are different qualities of PSA tape. It can be used to bond, shield emi/rfi, manage heat, mask off areas, protect surfaces, dampen vibration, suppress sound, seal, gasket and a ton of other solutions.
PSA tape is much different than heat-activated adhesives, which require heat to make them sticky.
PSA tape just takes a little bit of pressure to activate. You can find it in all industries and even the healthcare industry with athletic tape and wound-care solutions.
How is PSA Tape Made?
Adhesive tape in general consists of any surface coated with an adhesive or sticky substance. With pressure tape, you just need to press on the tape for it to stick to others.
An adhesive transfer occurs when the sticky substance transfers to another substance to make two things stick together. Think of envelopes or bag sealing, when you pull away from a waxy paper, not stuck permanently to the adhesive. The adhesive stays on the original envelope or bag, and when you press the adhesive side, it transfers adhesion to another material.
This occurs when you have an adhesion on one side of a material. There is a silicone-coated release liner protecting the adhesive. The material on which the adhesive sticks are called the web stock or face stock.
Tapes usually qualify as a single-coated adhesive tape. Usually, single-coated tape has a backing of 1 to 10 mils thick. The adhesive thickness is anywhere from 2 to 5 mils.
The single-coated tape is usually self-wound. Either paper or a film release liner line the tape. Sometimes a single-coated tape, like filament tape or duct tape, will have woven cloth or glass strands in it to reinforce it. These tapes are then paired with adhesive systems with a rubber base.
Electrical tape, masking tape, carton sealing tape, and just about all medical tapes qualify as single-coated tape.
The transfer tape will transfer adhesion to two different surfaces. It basically transfers the adhesive material to a surface, leaving another adhesive side out. It is simply like a clean line of glue that you place on a surface.
Transfer tape is tricky to use and requires a little bit of practice and skill.
The tape is a mass of adhesive film with a release coat on both sides of the tape. In other words, it's sticky on both sides. It works well to stick to odd surfaces.
To work best, the tape should have an adhesive that is more difficult to remove on one side. This allows the transfer tape to unwind properly.
When you think of double-coated tape, think double-sided tape. It is PSA with adhesive on both sides of the tape. You can use it for plastic films, tissue, any nonwoven, and many other materials. Typically, you can find double-coated PSA used as laminate and carpet tape.
To create double-sided tape, a company will coat two sides of a carrier material with adhesive. They then wind it up with a release liner to prevent the tape from sticking to itself. Typically, the company will coat the liner with a silicone release agent.
A self-wound tape is a type of tape coated on one side with a pressure sensitive adhesive and the other side with a release coating. The self-wound tape has no release liner coated with silicone on it. Duct tape, masking tape, and carton sealing tape all qualify as self-wound tape.
What Kind Of Adhesives are Used for PSA Tapes?
Adhesive companies use primarily three types of adhesives to create PSA tape.
Rubber is the least expensive PSA with the fastest sticking ability. Rubber adhesives have natural or synthetic rubbers in them. Companies will formulate those adhesives with resins, oils, and antioxidants.
Rubber adhesives work best indoors with less stress than an outdoor environment puts on them. They stick to low-surface energy materials. Many engineers formulate them with the idea of removing them quickly.
You can find rubber adhesive on masking tape, carton sealing tape, duct tape, and filament tape. Rubber does not feel tacky by nature, so engineers add resins to create the tacky adhesive needed.
Natural rubber has a higher molecular weight than synthetic rubber. It sticks well to LSE surfaces. Plus, you can remove it cleanly, but it does not do well in the heat, and it has a short lifespan.
Synthetic rubber is what engineers often refer to as "hot melt" adhesives. It is a thermoplastic with a lighter weight and shorter polymer chain that natural rubber. Thus engineers customize it more, and it sticks better to more surfaces.
Acrylic adhesives hold up better over time. They also tend to resist wear and tear by solvents and the environment. Plus, they can tolerate more heat than rubber adhesives and develop a stronger bond.
People tend to use acrylic both indoors and outdoors. It has a longer duration than other adhesives.
By nature, acrylic adhesives are tacky, but engineers often make them tackier. The polymers of the acrylic adhesives are flexible. Developers can adjust them during the manufacturing process to make the adhesive perform better.
Solvent acrylic comes from grains dissolved in a solvent. This adhesive does not adhere well to low surface energy plastics. They do stick better, though, than rubber.
Emulsion acrylic comes from spherical particles surrounded by surfactant in a water carrier. Emulsion acrylics cost less and are better for the environment than solvent acrylic adhesives. Their water-based properties make them less moisture resistant, so more people prefer a solvent acrylic.
Neither rubber nor acrylic creates the bond with silicone as a silicone adhesive does.
Silicone adhesives cost the most of all the adhesives. They can tolerate very high temperatures and thus handle extreme environments better than other adhesives.
Many people think silicone adhesives have a low sticking power because initially, they do not bond well. But time cures them, and they stick just fine.
Typically people use tape with silicone adhesive for important applications that expose the tape to extremely high temperatures and caustic environments. The best thing to stick to a silicone adhesive is silicone, so typically a user uses silicone adhesives in this circumstance.
You can find silicone adhesives in Teflon tapes, printed circuit board film making tapes, and silicone release liner splicing tapes.
Which Type of PSA Tape Should I Use?
When you're selecting the best type of PSA tape for your particular job, consider the following criteria:
1. What surface are you sticking the adhesive to?
2. What are the conditions that you'll expose the tape to? Will the temperature be hot and environment humid? Or will there be lots of gritty wind?
3. Why are you using this PSA? What's your purpose in it? What's it holding together or what do you want it to do?
4. How do you plan on applying the PSA?
5. Are you using the PSA as a permanent or temporary solution for a problem?
Make your decision based on the answers to these questions. Look for a tape that will withstand the conditions and work well with your surfaces.
Using Die Cut PSA
As stated earlier, pressure sensitive adhesives need just the light pressure of fingertips to activate. You do not need water, heat, or a solvent.
Because pressure sensitive adhesive tape is so sticky, your best bet for a tricky or particular job is a die cute PSA. When you have the PSA die-cut for the corners and shape that you need, you'll end up satisfied with just the right amount of adhesive.
When you do not use a die-cut PSA, you either have to cut the adhesive to the dimensions you want it and hope you get it right or you end up with some leftover adhesive and a gummy surface.
Strouse can laminate PSA to any material you need die cut.
A Low-Pressure, Sticky Solution
Now that you understand the ins and outs of pressure sensitive adhesive tape, you can purchase your best tape for the job you have at hand.
For all of your adhesive solutions, contact us. We'd love to help.