無碳複寫紙與雷射印表紙的再生技術

本研究係探討無碳複寫紙再生後產生再生紙漿低白度或具黑斑之原因，並同時探討雷射印表紙再生時之難脫墨之問題。試驗結果顯示在無碳複寫紙之再生作業前，施以顯色前處理，則進入脫墨程序時，可將有色粒子有效去除，可以有效解決回收再生紙漿白度低落之問題。至於彩色無碳複寫紙，如：黃色之廢紙，可利用二次漂白處理，在洗滌脫墨加入一部份H2O2 2%，並於浮選段後再增加一段2 ~ 6%之H2O2漂白，所得再生紙漿，白度可達80 %ISO以上，且具高白度安定性。紅色之廢紙，可施以次氯酸鹽加過氧化氫(NaOCl / H2O2)，二段漂白系統 (NaOCl 3 ~ 5%及H2O2 2 ~ 4%)，處理效果最為良好，白度可達75 %ISO以上且具相當之白度安定性。
另外，以傳統化學脫墨法進行雷射印表紙再生時產生不易脫墨及殘存墨斑之問題。試驗結果顯示可應用添加各種長碳鏈醇，以改善脫墨效率，長碳鏈醇具有將墨點凝聚功能，而使墨點粒徑變大之現象，尤其以十八醇及十八醇加丁醇此二組效果最佳。脫墨處理時，改變一般傳統的洗滌脫墨及浮選處理之方法，而以洗滌脫墨後並立即進入淨漿機之方法，以添加十八醇、十八醇及丁醇等二組脫墨劑，其墨點所佔面積可降至淨漿後的5 ppm，再生紙漿白度可達95 %ISO以上。另外本法為脫墨處理後，直接進入淨漿段，可省略浮選段，處理也可將墨點幾乎全部去除，堪稱節省相當之成本及水資源。

This study investigates the causes of low brightness or black spots in recycled pulp produced from recycled carbonless copy paper (CCP), as well as the difficult deinking issues encountered during the recycling of laser printer paper. The test results show that performing a pre-color development pretreatment prior to the recycling operation of carbonless copy paper enables effective removal of colored particles during the subsequent deinking process, effectively resolving the problem of low brightness in recovered recycled pulp. For colored carbonless copy paper waste, such as yellow waste paper, two-stage bleaching treatment can be adopted: add 2% hydrogen peroxide (H₂O₂) during washing deinking, and then conduct an additional 2–6% H₂O₂ bleaching stage after the flotation step. The resulting recycled pulp can achieve an ISO brightness of over 80% with high brightness stability. For red waste paper, a two-stage bleaching system using sodium hypochlorite (NaOCl) combined with hydrogen peroxide (H₂O₂) (3–5% NaOCl and 2–4% H₂O₂) delivers the best treatment effect, achieving an ISO brightness of over 75% with considerable brightness stability. Additionally, the conventional chemical deinking process for recycling laser printer paper often suffers from difficult deinking and residual ink spots. The test results demonstrate that adding various long-chain alcohols can improve deinking efficiency. Long-chain alcohols have the ability to agglomerate ink droplets, increasing their particle size; among these, octadecanol alone and the combination of octadecanol and butanol exhibit the optimal deinking effects. When conducting deinking treatment, replacing the conventional washing deinking and flotation process with a procedure that immediately feeds the pulp to a pulp cleaner after washing deinking, using the two deinking agent formulations (octadecanol alone, and octadecanol combined with butanol), reduces the ink spot area to 5 ppm after pulp cleaning, and the recycled pulp can reach an ISO brightness of over 95%. Furthermore, this method eliminates the need for the flotation stage by directly proceeding to the pulp cleaning step after deinking, which can almost completely remove ink spots and save considerable costs and water resources.