Non woven fabric is a fiber mesh material that is soft, breathable, has good water absorption, is wear-resistant, non-toxic, non irritating, and has no allergic reactions. Therefore, it has been widely used in medical, health, home, automotive, construction and other fields.
The production method of non-woven fabric
Melt blown method
Melt blown method is the direct melting and extrusion of polymer compounds, forming a jet of ultrafine fibers, and then fixing disordered fibers on a mesh forming belt through wind or drop. This is currently the most widely used non-woven fabric manufacturing technology.
Spunbond method
The spunbond method is a non-woven fabric made by directly dissolving chemical fibers into a solution state, and then forming a fiber network structure on the network forming belt through coating or impregnation, followed by curing and finishing processes. This method is suitable for fibers with longer length and larger coarseness.
Wet preparation
Wet preparation is the process of preparing non-woven fabrics using fiber suspensions. Firstly, disperse the fibers into the suspension, and then prepare the pattern through spraying, rotary screening, mesh belt molding, and other methods. Then, it is made through processes such as compaction, dehydration, and solidification. This method is suitable for fibers with smaller diameter and shorter length.
Is non-woven fabric made on top or bottom of the roll?
In general, the production of non-woven fabric is carried out on top of the roll material. On the one hand, it is to avoid fiber contamination by impurities on the coil, and on the other hand, it is also to better control parameters such as tension and speed during the manufacturing process, in order to obtain higher quality non-woven fabric products.
The specific process of making non-woven fabric
1. The specific process of preparing non-woven fabrics by melt blown method:
Spray spinning – fiber dispersion – air traction – mesh forming – fixed fibers – heat setting – cutting and sizing – finished products.
2. The specific process of preparing non-woven fabrics by spunbond method:
Preparation of polymer compounds – Processing into solutions – Coating or impregnation – Heat setting – Forming – Washing – Drying – Cutting to size – Finished products.
3. The specific process of wet preparation of non-woven fabric:
Fiber loosening – mixing – preparation of adhesive solution – horizontal mesh belt – fiber conveying – mesh belt forming – compaction – drying – coating – calendering – cutting to length – finished product.
How is non-woven fabric made?
Let’s first understand how fibers are made. Natural fibers are inherent in nature, while chemical fibers (including synthetic fibers and synthetic fibers) dissolve polymer compounds in solvents to form spinning solutions or melt them at high temperatures. Then, the solution or melt is extruded from the spinneret of the spinning pump, and the jet stream cools and solidifies to form primary fibers, The primary fibers are then subjected to corresponding post-processing to form short fibers or long filaments that can be used for textiles.
Weaving fabric is the process of spinning fibers into yarn, which is then woven into fabric by machine weaving or knitting. Non woven fabrics do not require spinning and weaving, so how does it turn fibers into cloth? There are many production processes for non-woven fabrics, and each process is different, but the core process includes fiber mesh forming and fiber mesh reinforcement.
Fiber web formation
“Fiber networking”, as the name suggests, refers to the process of making fibers into a mesh. Common methods include dry networking, wet networking, spinning networking, melt blown networking, and so on.
Dry and wet web forming methods are more suitable for short fiber web forming. Generally, fiber raw materials need to be pretreated, such as pulling large fiber clusters or blocks into small pieces to become loose, removing impurities, mixing various fiber components evenly, and preparing before forming the web. The dry method generally involves combing and stacking pre treated fibers into a fiber mesh with a certain thickness. Wet process mesh formation is the process of dispersing short fibers in water containing chemical additives to form a suspension slurry, which is then filtered out. The fibers deposited on the filter mesh will form a fiber mesh.
Spinning into a web and melt blown into a web are both spinning methods that use chemical fibers to directly lay the fibers into a web during the spinning process. Spinning into a web is the process in which a spinning solution or melt is sprayed out from the spinneret, cooled and stretched to form a certain degree of fine filament, which forms a fiber web on the receiving device. Melt blown mesh, on the other hand, utilizes high-speed hot air to extremely stretch the fine flow sprayed by the spinneret, forming ultrafine fibers that then aggregate on the receiving device to form a fiber network. The fiber diameter formed by melt blown method is smaller, which is beneficial for improving filtration efficiency.
Fiber mesh reinforcement
The fiber mesh made by different methods has loose internal fiber connections and low strength, making it difficult to meet usage needs. Therefore, it needs to be reinforced. The commonly used reinforcement methods include chemical bonding, thermal bonding, mechanical reinforcement, etc
Chemical bonding reinforcement method: The adhesive is applied to the fiber mesh through impregnation, spraying, printing and other methods, and then subjected to heat treatment to evaporate water and solidify the adhesive, thereby reinforcing the fiber mesh into a cloth.
Hot bonding reinforcement method: Most polymer materials have thermoplastic properties, which means that they will melt and become sticky when heated to a certain temperature, and then solidify again after cooling. This principle can also be used to reinforce fiber webs. Commonly used are hot air bonding – using hot air to heat the fiber mesh to achieve bonding reinforcement; Hot rolling bonding – using a pair of heated steel rollers to heat the fiber mesh and apply a certain amount of pressure to strengthen the fiber mesh through bonding.
Summary
Non woven fabric is a widely used fiber mesh material that has become an indispensable and important component in modern industrial production. By using different production methods such as melt blown, spunbond, and wet preparation, non-woven fabric products with different characteristics can be obtained, which can meet the needs of various fields for non-woven fabric materials
Post time: Mar-12-2024