The process of creating laminated nonwoven products has to be done with the proper process controls in place to ensure the highest quality of the finished product. However, not all laminates are the same.
While some are made with a heavier construction, there are many that rely on their lighter construction to provide both protection and a greater comfort, especially with regards to wearable products.
Examples of products that are made with lightweight laminates include:
- Surgical masks
- Surgical gowns
- Feminine hygiene products
When it comes to produce any nonwoven laminated composites, it is important to ensure that the individual layers of the said composite are not compromised during the lamination process. This is particularly the case when producing lightweight composites that are thinner and more fragile than their heavyweight counterparts.
With this in mind, there are three strategies you can use to boost lightweight laminated nonwoven production while minimizing the risk of obtaining a defective product.
1. Use high-quality materials
The materials you use to produce the composite will play a huge role in its resulting weight and strength. When it comes to nonwoven materials, you want something that exhibits good tensile strength while remaining thin and light. The choice is between synthetic and natural fibers and you can use any combination of them.
Synthetic fibers, such as polyester, polypropylene, polystyrene and other polymers, are the best choices for a strong and lightweight material that can be made water resistant, breathable, high temperature resistant, soft and printable. To increase comfort and breathability of some products, a resistant and light material such as cotton can be added.
With regard to the bonding material, polyethylene film will provide the best adhesion while keeping the overall composite light, soft and flexible. Plus, polyethylene film can be used in different lamination processes, providing a highly effective waterproof barrier, high strength and anti-tear capabilities.
2. Improve tension controls
Tension control is one of the most important factors in creating a high-quality laminated nonwoven products. If the web tension is off in either direction – too high or too low – you risk tearing and damage to one or more of the layers in the resulting composite. This applies even more to lightweight materials: The thinner and more lightweight they are, the easier they are to damage, even when creating laminated nonwoven composites that are tear resistant. Improper tension control can also create wrinkles, areas where the bonding is incomplete and incompatible width between the layers.
It is critical that you are fully aware of the tensile strength of the materials you are using in your composite: with lightweight materials, you need to be absolutely precise with tension settings, because if you are off by even the smallest increment you may damage them.
In this case, it’s best to use a smart lamination system, like the A.Celli F-LineⓇ, that utilizes sensors, cloud technology and a software that allows you to monitor what is happening at every step of the process – unwinding, lamination, slitting, and winding.
When you have this bird’s eye view of the entire process and the system can detect defects and relay the production data in real-time, you can make minute adjustments to tension settings without halting production. This ensures that tension settings remain always optimal, thus obtaining a top-quality final product.
3. Control production speed
The speed of the production line must also be controlled throughout the lamination process, as speed can affect the web tension. In addition, particularly when winding the final composite, incorrect speed can produce a defective reel with the presence of telescoping, wrinkles and trapped air.
Ideally, you want production to run as quickly as possible without compromising the quality of the final product. In nonwoven lamination, this means the speed at which the individual layers are unwound and fed into the lamination machine, the speed at which they pass through said lamination machine and the speed at which they are slit and rewound to form the finished reels are all critical to obtain a quality product.
As with tension, a machine equipped with sensors and cloud connectivity can measure machine speed at every stage of the process and detect defects in the material. These data can be analyzed and passed on to you so you can make the needed adjustments to machine speeds during operations. This capability will ultimately allow you to find the optimal production speed and will ensure the integrity of each layer in the laminated nonwoven you are producing, as well as the integrity and quality of the final product.
When you have firm control over these three aspects of the lamination process, you will be able to create lightweight nonwoven laminates that are strong, effective and comfortable with minimal risk to the integrity of the individual layers and the final composite.