The Process And Performance Of Silk/ES Fiber Spun-lace Composite For Disposable Hygiene Covering Materials

With the loosening of the family planning policy, the sharp increase of old population invarious countries and the accelerated pace of life, the demand of baby diapers, adult diapers andother disposable hygiene products is growing. Currently, it is easy to result in erythema, pruritusand other issues with prolonged use of disposable hygiene products, because the coveringmaterial of hygiene products is contact with human skin intimately, its breathability, comfort,dryness and other indicators are crucial. To solve this problem, a new covering material, which isfabricated by new raw materials and innovative technology, has been produced. The processcombines the silk fibers, with widely used through-air thermal bonded nonwovens, aiming todevelop green and natural, good healthy silk/ES nonwovens with properties such as permeability,dry and comfort, silky smooth to touch, softness.Silk webs and through-air thermal bonded nonwovens are compounded through spun-laceprocess. The results show that through-air thermal bonded nonwovens not only have no negativeeffect on the superior performance of silk, but also improve some mechanical properties. Inaddition, they can reduce the consumption of silk so that the cost will be lower.Hydrophilic agent TF629is chose for silk/ES nonwovens hydrophilic finishing, which isless stimulating. After that, three factors (drying temperature, drying time, the volume fraction ofhydrophilic agent), which have influence on liquid penetration time and wet back, are discussed.The optimal hydrophilic finishing parameters are as follows: drying temperature is70℃，dryingtime is7min, the volume fraction of hydrophilic agent is0.7percent.This study is a research of the relationship between process parameters (spun-lace pressure,surface density, mesh number of delivery belt, the volume fraction of hydrophilic agent, dryingtime, drying temperature) and product properties (tensile properties, breathability, liquidpenetration time, wet back and bending properties). The results indicate that the breakingstrengths of silk/ES nonwovens in machine direction and cross direction both increases and thendecreases with increasing spun-lace pressure, but shows upward trend with increasing surfacedensity; permeability reduces as surface density and spun-lace pressure increases; bending rigidity and bending hysteresis both turn bad while surface density increases; liquid penetrationtime reduces when spun-lace pressure increases and increases when surface density raises; wetback enhances as spun-lace pressure increases, and decreases as the surface density increases. Tointegrate the requirements of all the indicators, the optimal spun-lace process parameters are asfollows: number of combing is three, spun-lace pressure are30bar、45bar、45bar、50bar,surface density is32gram per square meters.In order to expand the diversity of covering materials, based on the study of silk/ESnonwovens, a semi-open-cell structure of silk/ES nonwovens has been developed by changingthe mesh number of delivery belt for spun-lace process. By comparing the permeability,penetration time and bending properties of unperforated silk/ES nonwovens and semi-open-cellsilk/ES nonwovens, the results show that dry, comfort and softness performances of25meshsemi-open-cell silk/ES Nonwovens, are slightly poorer than that of unperforated silk/ESnonwovens, but tensile properties, permeability and liquid penetration time are all better thanthat of unperforated silk/ES nonwovens; the hole in upper layer of12mesh semi-open-cellsilk/ES nonwovens is too large, although the permeability increases, the wet back can’t meet therequirements of the sanitary covering materials.