Yongte has developed latest multi-layer co-extrusion technology for WPC extrusion machine, it can acheive multi-layered wood grain effects on surface of WPC decking
WPC Co-extrusion process innovation
Multi-layer co-extrusion technology: use multiple extruders to extrude materials of different colors and ingredients at the same time, and through a specific mold combination, make each layer of material blend with each other during the extrusion process while maintaining its own characteristics. For example, first extrude a core layer containing wood powder and basic color, and then co-extrude one or more layers of surface layers containing different colors, additives or texture effects on its surface. The surface layer can achieve richer color changes and texture details by adding special masterbatches or modifiers, thereby forming a multi-layer wood grain effect from the core layer to the surface layer on the same product surface.
Precise control of extrusion parameters: precise control of extrusion temperature, pressure, speed and other parameters. Set different temperatures and pressures at different stages to make the flow and fusion of materials in the mold more uniform and orderly. For example, in the key area of extrusion wood grain effect, appropriately reduce the extrusion speed to allow masterbatches and wood powder and other ingredients to have more time to distribute and arrange, forming clearer and more delicate wood grain; while in other parts, parameters can be adjusted to ensure overall production efficiency and product quality.
WPC co extrusion Mold design
Special mold structure: design molds with specific shapes and textures. The flow channel and cavity structure inside the mold are carefully designed so that the material is subjected to different shear forces and pressures during the extrusion process, thus forming a natural wood grain pattern on the surface. For example, tiny bumps, grooves or textures are set on the mold surface. These textures will be transferred to the surface of the product when the material is extruded, and work together with masterbatch and wood powder to enhance the three-dimensional and layered sense of the wood grain.
Co-extrusion materials
Use special masterbatch: Flow masterbatch is a special masterbatch that can be used to accurately control the color of plastic products and can produce special texture effects such as imitation marble and wood grain. By selecting the appropriate flow masterbatch series and combining it with a plastic matrix such as polyethylene, a unique wood grain-like flow texture can be formed on the surface of the wood-plastic co-extruded product.
Surface treatment
Embossed and frosted: The surface of the product is post-treated by embossing and frosting after extrusion. The embossing roller is used to extrude wood-like textures on the softened board surface. The working surface of the embossing roller includes a number of convex areas and a plain area set between two adjacent convex areas. The convex area forms a texture unit, and the plain area forms an interstitial unit. The surface of the plain area is a rough surface with dense and evenly distributed fine protrusions and depressions, so as to form a wood texture with a frosted effect, making the wood grain more realistic and increasing the sense of layering and texture.
