Preparation of repeated washable compounded papers using wasted tea leaves by addition of binder

An attempt was made for the preparation of compounded papers using wasted tea leaves that could withstand repeated washing. Emulsion Polyamide- Epichlorohydrin copolymer was added as a binder to slurry containing crushed wasted tea leaves and hemp for paper making. When the resulting paper was measured for tensile strength under a wet condition, it was found markedly improved over a control paper without the emulsion. For instance, tensile strength was 2.1 N·m/g for a compounded paper containing 90 wt% hemp and 10 wt% wasted tea leaves but no binder, whereas the addition of the binder at 0.75 wt% improved tensile strength to 16.8 N·Vg. Compounded papers using wasted tea leaves were also very effective for deodorizing ammonia gas ; a paper containing a small amount, 10 wt%, of wasted tea leaves decreased the ratio of residual odor to 0.6 % in three hours. The addition of the binder was also found to keep the deodorization effect of the paper. Furthermore, a compounded paper using wasted tea leaves was repeatedly subjected to washing. The addition of the binder strikingly improved the washing durability of the paper that was subjected to washing repeatedly; at an addition level of 0.75 wt%, the paper did not show any damage even after it was washed repeatedly 20 times. Further, the deodorization effect after washing was maintained. In fact, the ratio of residual order was very small at 2.1% or less in an hour even after the 20 times washing.