PURPOSES : This study describes the experimental findings on the mechanical properties of calcium aluminate cement (CAC)-based repair mortars with or without natural cellulose fiber (NCF). Additionally, the effect of adding NCF to the reduction of fugitive dust in the CAC powder was examined. METHODS : To produce mortar, four different levels of NCF (0.0.5, 1.0, and 2.0% by binder weight) were adopted, and the water-binder ratio was fixed at 0.485. The flow, strength characteristics, absorption, and surface electrical resistivity of the mortars were measured at predetermined periods. Additionally, SEM observations were performed to examine the microstructural changes and hydrates formed on the 28 day-mortar samples. RESULTS : The addition of NCF led to a decrease in fugitive dust. Regarding the mechanical properties of the mortars, that with 0.5% NCF exhibited a better performance in terms of strength development and surface electric resistivity compared to those of other mortars. However, the addition of NCF was less effective in the enhancement of the absorption of mortars. Further, we discovered that the microstructures of the mortars with additional NCF were comparatively dense compared to those without NCF. CONCLUSIONS : The appropriate addition of NCF can enhance the performance of CAC-based repair materials. However, further studies on the durability of CAC with the addition of NCF are needed to determine the optimal mixture.

본 연구에서는 인체 친화적이고 환경 친화적인 패션제품 소재기획을 위한 기초 자료를 제시하고자 수행되었다. 이를 위해서 4종의 섬유소 소재를 대상으로 염색조건을 달리하여 천연 쪽 염색을 실시하여 색채특성과 색채감성을 평가하였으며, 이러한 특성이 선호도에 미치는 영향을 분석하였다. 쪽 염색된 직물은 모두 중, 저명도와 저채도의 남색(PB)을 구현하였다. 이들 직물의 색채특성은 섬유종류와 염색조건에 따라 유의한 차이를 보였다. 쪽 염색된 직물에 대한 색채감성은 스포티 감성, 클래식 감성, 내추럴 감성 등 3가지 요인으로 분류되었다. 이러한 색채감성은 섬유종류와 염색조건에 따라 부분적으로 유의한 차이를 나타내었다. 또한 쪽 염색 직물의 색채특성과 색채감성 요인 간에는 부분적으로 유의한 상관관계를 보였다. 쪽 염색 직물의 색채 선호도에 영향을 주는 요인으로는 색채감성 요인 중에서 클래식 감성과 스포티 감성, 색채특성에서는 L*값인 것으로 나타났다.

The purpose of this research is to revive the colors of combination dyeing and mixed dyeing with natural dyestuffs. The fabrics used were cotton and rayon. The natural dyestuffs used in this research were indigo, Phellodendron amurense, and Caesalpinia sappan. The effects of combination dyeing were as follows. First, all samples showed deeper colors. Second, according to the results of the surface K/S measurement, while the surface K/S of cotton was over 15, that of rayon was over 17. Third, the results of the light fastness measurement showed the superiority (by over grade 4) of all the samples, except in the case of rayon fiber sample no. 6 (which had been pre-dyed with indigo five times before being dyed with P. amurense once and then being dyed with C. sappan once). In the color fastness to washing measurement, all fibers showed superiority (by over grade 3~4). In addition, the color fastness to dry cleaning of all fibers was satisfactory or excellent (by over grade 3). Fourth, according to the results of the tensile strength measurement, it tended to decrease in the case of cotton and increase in the case of rayon. Fifth, the results of the density measurement showed that the density of cotton decreased by about 15~20% in the case of warp and 10% in the case of weft for all samples. The density of rayon decreased 20% in the case of warp for all samples and increased 30% in the case of weft for all samples.