Principle of spunlace consolidation process

The spunlace (spunbond) technology to consolidate spunbond webs is a new process developed in recent years. The process principle is that the high-pressure water flow with a pressure of up to 40Mpa generated by a water pump is sprayed through a water jet hole with a diameter of ≤0.15mm Then, a curtain of water needles distributed along the entire width of the fiber web is formed. The water needles impact the unconsolidated web at high speed. The water needles reflect when penetrating the web and after passing through the web, making the fibers entangled to form a shape. A non-woven fabric with a certain strength is fixed, and the high-pressure water flows through the fiber net and enters the filtration system for processing and recycling. After drying the moisture of the consolidated web, it becomes a spunlace product.

Features of spunbond spunlace nonwovens

Compared with the hot-rolled spunbond fabric, the spunlace spunbonded nonwoven fabric has the characteristics of undamaged fiber web, fluffy hand feeling, good air permeability, and greater strength. This is because after the continuous filament web is consolidated by spunlace, the consolidation point is formed by the bending and entanglement of the fiber, the fiber remains continuous and the fiber web is not damaged, and the web structure consolidated by hot rolling, the consolidation point It is formed by partial plasticization of fibers and fiber nets, and the fiber nets have become airtight and thin. Since the fibers of the spunlace cloth are not damaged, the breaking strength of the spunlace cloth is greater than that of the hot-rolled spunbond fabric, and the tear strength is higher than that of the hot-rolled spunbond fabric. Since the spunlace web is not pressed by a similar hot-rolling roll, the thickness of the spunlace fabric of the same specification is 30-50% higher than that of the hot-rolled spunbond fabric, so the spunlace fabric feels more fluffy and has better air permeability.

Spunbond web spunlace consolidation production process

When consolidating spunbond webs by spunlace method, the process and equipment before forming the web is the same as the general production line for consolidating spunbond webs by hot rolling, only the spunlace system and drying system are used instead of the hot rolling mill . The general production process of single-component spunbond webs during spunlace consolidation is as follows:

Raw material supply → screw extruder → melt filtration → spinning pump → spinning box → melt spinning into a web → pre-wetting → front spunlace → back spunlace → vacuum dehydration → pre-drying → finishing → heating and drying, Finalizing → online inspection → slitting, winding → packaging → product

Basic composition of spunlace system

The spunlace system is a relatively complex system, mainly including high-pressure water pump, spunlace machine, water treatment system and drying system.

The high-pressure water pump is generally a three-plunger high-pressure pump, which is used to generate high-pressure water.

The spunlace machine is the core equipment of the spunlace process. It is used to consolidate the fiber web into a cloth. According to its working mode, there are mainly two types: drum type (roller type) and flat wire type.

Since the spunlace production line needs a lot of process water during its operation, the water treatment system is to recover, purify, and recycle process water.

The drying system includes mechanical dehydration and heating and drying. Mechanical dewatering generally uses negative pressure suction to remove most of the unbound water from the product that has just come out of the spunlace system and has a high water content. Hot air penetration dryers are commonly used for heating and drying to remove the moisture in the web. Because drying moisture consumes a lot of heat, the energy consumption of spunlace cloth is also higher, and the production cost is higher than that of hot-rolled spunbonded cloth. The quality is better than hot rolled spunbond fabric.

When the spunlace consolidation process is adopted for the web, the plane layout, elevation layout, energy supply, plant area, investment scale, production cost and operation management of the spunbond production line are much larger than those of ordinary hot-rolled spunbond lines. The difference.