In the process of hot air penetration bonding composite research, the processing technology of baby diaper kinds of materials popular in the Japanese market was studied, and the SEM electron microscope was carried out on the conduction layer used in some products. In the SEM images, it can be seen that fibers and fibers are bonded together by fiber melting rather than chemical adhesives, and the two materials are produced by a hot melt bonding process. Therefore, based on the above analysis, it was decided to use the hot melt bonding process to produce the composite material. On the basis of digesting and absorbing the imported hot air penetration bonding production line, this project studies the structure, performance, key process and industrialization of hot air penetration bonding composite materials, filling the gap in the same field at home and abroad, reaching the international advanced level .
The industrial production of this subject is a new concept of composite diversion layer material. The raw materials of the composite fibers are different, and the fiber arrangement is also very complicated. The fiber fineness of this structure is relatively thick, and the fiber directional arrangement structure should be adopted to improve the diffusion speed of the liquid in the fiber web; the damping layer has small fiber fineness and random arrangement of fibers, which not only has a certain water permeability, but also can prevent the liquid from permeating too fast. , unable to diffuse in the diversion layer. The bicomponent fiber hydrophilicity, fineness, fiber arrangement structure, fiber mesh density, etc. of the diversion layer and the damping layer need to be carefully studied.
The hot air penetration bonding production line used in this project has its own characteristics for carding and web formation. It uses two carding machines to form webs in series, which can increase production speed, improve product quantification, and improve product uniformity. However, the two carding machines use the same carding technology and can only card 1.5~3d fibers. In view of the deficiencies of the carding system of the above-mentioned production line, this project will propose a new technical transformation plan for the second carding machine of the carding system. The fineness of the fibers used in the guide layer has reached 6~8d or more, so the card clothing configuration of the main carding system needs to be re-studied.
The guide layer requires fiber orientation in the fiber web, so it is necessary to design a new cohesive roller web forming system, study various output editing speeds and card clothing configurations in the cohesive high-speed web system, and by superimposing with the damping layer fiber web, keep the fibers Oriented arrangement, high-speed output fiber web. The consolidation and compounding of the diversion layer and the damping layer adopt the hot air penetration bonding process, further study the oven insulation structure, reduce the production energy consumption, further optimize the temperature control system accuracy, ensure the temperature accuracy in the oven, optimize the design of the oven internal structure, eliminate the The difference in hot air flow ensures uniform temperature distribution in the oven, and ultimately ensures the consistency of mechanical properties in the long section and the width direction.
Through this research, the optimization of baby diaper structural materials can better improve product performance. At the same time, it also provides a plan for domestic technology development and research direction.