The Study On The Structure And Performance Of The Absorption Core Layer Of Paper Diapers

With the growth of the economy,the disposable hygiene industry has continued to grow in recent years,especially for baby diapers and adult diapers.However,the use of diapers in China started relatively late,and there is a widespread problem in rural areas that user's skin is exposed to moist environment full of bacterial for a long time because of diapers cannot be replaced in time,causing the skin diseases such as diaper rash and eczema.Therefore,in order to optimize the absorbent core structure of diaper,it is required to solve these issues that the design of the diaper core structure and the performance of the superabsorbent gel after absorbing water,which will have great significance for the development of the Chinese diaper market.The goal of this paper is to investigate the effects of different core structures on the wicking properties of diapers and the gel diffusion of multilayer core structures.Therefore,according to the needs of the subject,four kinds of diapers with different core structures were designed as following:fluff pulp + fluff pulp / super absorbent resin core,single layer fluff pulp / super absorbent resin core,single layer non-woven composite core,nonwoven composite core + fluff pulp / super absorbent resin core.Then,the above four core diapers were subjected to the standard test of liquid permeability,and the test results were compared and analyzed according to the core structure.The test analysis shows that the four core structures have very good liquid absorption performance,and the liquid absorption ratio is between 15-20 times.There is a problem of poor permeation and liquid absorption performance after the liquid absorption of the composite core of the nonwoven material.The difference of the liquid absorption speed between the two experiments is large,the maximum is 6.88 seconds;the difference between the diffusion lengths of the two experiments is small,the minimum is 1.86 cm.The liquid absorption performance of the fluff pulp core structure is better,the minimum amount of reverse osmosis is 47.2 mg,and the minimum penetration is 7.6 mg,which can firmly lock the liquid in the core structure.Secondly,the gel problem of superabsorbent resin between layers of multi-layer absorbent core structure and the influence of different core coating materials on the diffusion of core were studied in this thesis as well.First of all,it is necessary to select the superabsorbent resin material and coating material,then design the core structure.Three kinds of superabsorbent resins(SAP)with different particle sizes of 2.06 mm,1.49 mm and 1.74 mm were considered respectively,and the liquid absorption performance were tested.Both of SAPs with the particle size of 1.49 mm and 1.74 mm have better liquid absorption performance with the liquid absorption above 50 g/g;and the SAP with the particle size of 2.06 mm have poor liquid absorption performance.Then,the coating materials of the core were taken into account.According to the different functions of the top sheet and the back sheet materials,hot air bonded hydrophilic nonwovens,pure viscose spunlaced nonwovens and hot air bonded hydrophobic nonwovens,pure polyester spunlaced nonwovens were selected as the materials for the top sheet and the back sheet of the core,respectively.Finally,eight kinds of fluff pulp absorbent cores with different structures were designed to study the gelation and diffusion of different structural cores.The test results show that the four core structures obtained by decreasing the liquid-absorbent performance along the direction of urine conduction have the best liquid absorption performance,the liquid absorption is above 400 grams,and the liquid absorption ratio is 20 times.The core structure does not easily reach the upper gel state,thereby avoiding hindering the movement and absorption of the liquid to the lower core structure.On the other hand,the core structure covered by the hot air cloth has the fastest liquid absorption speed,which is about 8 seconds;the surface layer is the pure viscose spun cloth coated core structure,the surface layer has the best diffusion performance,and the diffusion shape is oval,and the third surface diffusion long axis length is 23 cm;the bottom layer is pure polyester spun cloth coated core structure,the bottom layer has the best damping performance,and the third bottom diffusion long axis length is at least 12 cm.Therefore,in order to promote the diffusion of the surface layer and the damping diffusion of the bottom layer,the surface coating material should be a nonwoven fabric made of hydrophilic fibers,and the material structure is fluffy,and the fiber arrangement direction should be arranged along the liquid diffusion longitudinal direction;The covering material should be a non-woven fabric made of water-repellent fiber,and the material structure is dense.