A Study On The Structure And The Properties Of Hot Air Through Bonding Composite ADL Materails

ADL is the non-woven material applied in the sanitary napkin and diaper. In China, ADL material is still a new concept, our study on it is limited. Large foreign companies started to study it very earlier. At present, the 90% high-end ADL materials used in the domestic disposable products rely on imports, related technologies are controlled by foreign companies, such as Kimberly-Clark, Procter & Gamble, Unicharm and Kao. In this context, DongHua University and ShaoXing County Zhuangjie Nonwoven Material Co., Ltd., applied a ZheJiang province 2008 major industrial projects " Key technology and Industrialization of the hot air through bonding composite ADL material", through the studies on the process, structure and properties of ADL material, master the independent intellectual property rights of ADL material's critical technologies.The composite structure of fiberweb was firstly studied, by studying the distribution mechanism, we found that the liquid spread in the longitudinal direction of ADL material, it can enlarge the suction area of the absorbent core; the liquid spread in the vertical direction of ADL material, it can increase absorption capacity of the absorbent core. So we designed a novel composite ADL material, the composite ADL material included the conventional ADL and damping layer. ADL have the directional fiberweb structure, so it can increase the liquid proliferation in fiberweb; damping layer have the random fiberweb structure, which requires both a certain degree of permeability, but also to prevent the liquid from infiltrating too quickly to spread in the longitudinal direction of ADL material, so this particular structure can maximize the liquid proliferation and infiltration in the longitudinal and horizontal direction separately.Secondly, the coarse denier bicomponent fiber carding process was discussed, the hot air through bonding production line has its own characteristics, which uses two carding machines in series to form a fiberweb, it can increase production speed, improve product gsm, improve product uniformity. However, the 2 carding machines use the same technology, which can card 1.5 ~ 3d fiber. In response to such deficiency, the topic proposed some technical reform to make the carding machine to card the 6 ~ 8d even larger fiber.Finally, compound web-forming and hot air consolidation technology were studied, though designing the novle control double random system, to keep the fibers in oriental arrangement, consolidate the ADL and damping layer by using the hot air through bonding technology. Through the transformation of the curtain temperature sensors and pre-cooling equipment, make the fiberweb fluffy, soft and the hot air oven consume less energy. Through the above study, we trial the product, and the sample have the advantage of fluffy, good absorption capacity and distribution performance, the shortest strike through time is 1.76s, run-off is 0 g.