전통염색지인 아청지(감지 : 쪽물 염색지)의 재현을 위해 고문헌 감지의 색상을 조사한 후 인도 쪽 분말과 전통니람법에 의해 제조한 염색한지의 염색특성을 검토한 결과는 다음과 같다. 인도산 쪽 분말로 제조한 염액으로 1회 염색한 경우 염색시간이 증가함에 따라 염착량과 색차 모두 증가하였으 며, 특히 염색시간 15분까지는 급격히 증가하였으나 이후 85분까지는 매우 완만하였다. 그러나 2회차에는 염색시간이 5분에서 40분까지는 색차나 염착량 모두 1회때 보다 약간 높거나 거의 같았으나, 40분 이후에는 오히려 감소하였다. 따라서 염색시간은 15분~30분 정도가 적정할 것으로 생각된다. 전통니람을 전통발효에 의해 얻은 쪽물로 반복염색(1회: 15분 염색, 15분 발색)하면서 염색횟수에 따른 색상을 비교한 결과, 1회의 염색에서의 색상은 1.9G로 그레이톤이었으나, 염색횟수가 증가함에 따라 색상도 G→BG→B→PB로 변화하며 색차와 염착량 모두 증가하여 고문서 감지의 색상인 PB는 8회의 염색한지에서 나타났다. 고문서 감지의 색차, 염착량 및 색상과 비슷한 염색횟수는 30번째로 색차 9.82, 염착량 8.56, 색상 6.0PB였다. 그러나 염색횟수는 염액의 인디고 함량에 크게 좌우되며, 인디고 함량이 높으면 염색횟수는 단축 가능할 것으로 생각된다.
The study investigated the dyeing properties of Hanji dyed with Indian indigo powder and Niram, a traditional mud-like indigo precipitate with shell-lime, to reproduce Achoengji (or Gamji), the Korean traditional indigo-dyed paper. The dyeing yield and color difference increased with increasing of the dyeing time in the first dyeing process, which was performed by a stepwise manner of increasing dyeing time of yellow Hanji by 5 minutes from 5 to 85 minutes using Indian indigo powder. They increased rapidly up to 15 minutes, and then steadily increased until 85 minutes. The second dyeing process was repeated with the dried indigo-dyed Hanji as the same dyeing manner in the first dyeing process. The dyeing yield and color difference were similar or a bit higher to those of the first process from five to forty minutes of dyeing time. After 40 minutes of the dyeing, those even were decreased unexpectedly. From these results, it was believed that the appropriate dyeing time was between 15 and 30 minutes. A dyeing solution produced by the fermentation of Niram in a traditional method was also used to compare the color changes by the repetition number of dyeing (15 minutes dyeing – 15 minutes development). The dyeing yield and color difference increased with an increase in the dyeing number, and the hue was also changed G→BG→B→PB, respectively. The hue was 1.9G dyed indigo paper in the single time, and the PB color of dyed indigo paper was started to appear after the 8-times dyeing. The color factor similar to those of the antique indigo paper used in this study was appeared in 30-times dyed indigo paper, showing a color difference of 9.82, color yield of 8.56, and hue of 6.0PB. Nevertheless, the dyeing number could be reduced by the fact that the color factor of indigo-dyed paper depended on the indigo contents in the fermented indigo solution.