Engineer Spotlight: Cortland Biomedical’s Julia Wright Discusses Warp Knitting

Cortland Biomedical Textile Process Engineer Julia Wright Discusses Processes and Advantages of Warp Knitting

Q: What are the key advantages of warp knitting over other textile production methods for biomedical textiles?

A: There are significant advantages of warp knitting over other textile production methods for biomedical textiles. For fabrics that require high burst strength and are highly conformable, warp knitting allows for greater flexibility in the design of the fabric. Warp knitting also offers the ability to control pore size and density, which is particularly important when considering the need to support high cell in-growth potential within the body. These specific properties and controllable structures allow for the tailored creation of fabrics which adhere to required performance characteristics for advanced medical devices.

Q: Can you describe in more detail how the warp knitting process allows for the creation of fabrics with specific properties?

A: During the warp knitting process, vertical yarns are fed through guide bars which loop the yarn around needles along a needle bed to create the desired pattern. The ability to control the number of guide bars used, the swinging and shogging motions of the guide bars, and the threading of the warp yarns allows for the creation of fabrics with specific constructions, resulting in different technical properties. For example, by manipulating the pattern of the guide bar’s swing and shog motion, it is possible to create fabrics with varying pore sizes and yarn structures.

Q: Can you elaborate on a specific application of warp-knitted biomedical textiles that has had a significant impact on patient care?

A: Warp knitted textiles have had a significant impact on tissue regeneration. Biomedical textiles made using warp knitting techniques have been used to create implantable scaffolds that support the regeneration of tissues in multiple areas of the body. These scaffolds have the unique ability to mimic the structure of natural tissue, allowing for more effective healing and recovery.

Q: What types of materials are commonly used in warp-knitted biomedical textiles, and how are these materials selected?

A: The most commonly used material for warp-knitted biomedical textiles is PET (polyethylene terephthalate). PET is strong but not so strong that it does not allow for give when needed, or risk tearing through internal tissue. Warp knitting is also well-suited for working with monofilaments and resorbable materials. Materials are selected based on the strength they can provide and how long they will be placed in the body. PET is the primary choice due to its strength and compatibility within the body.

Q: How does the durability and strength of warp-knitted biomedical textiles compare to those produced using weft knitting methods, and why is this important for medical applications?

A: While both warp and weft knitting methods have their advantages and disadvantages, warp knitting is generally considered to be more durable and stronger than weft knitting methods. The reason for this resides in the vertical loop structure, providing greater flexibility and strength, while preventing unraveling. The gauge capabilities of warp knitting machines also allow for a tighter density of material as well. This is important in medical applications where the textiles will be subjected to repeated use and need to maintain their shape and strength over time.

Q: What are your capabilities for warp knitting?

A: At Cortland Biomedical, our knitting capabilities include but are not limited to warp and circular knitting. Our warp knitting capabilities allow us to create a wide range of biomedical textiles with specific properties and well-controlled structures to meet our customers’ needs. Pile, tubular, and spacer fabrics are examples of products we can produce.