基于蓝湿革脱铬坯革的硅鞣工艺研究

Silicon Tanning Technology based on Dechromed Wet Blue Leather

采用草酸和硫酸的混合物作为脱铬材料对蓝湿革进行脱铬处理,比较和分析了脱铬过程中酸用量、处理时间对皮革收缩温度和铬含量的影响。在此基础上,研究了基于蓝湿革脱铬坯革的硅鞣工艺技术,测试比较了蓝湿革脱铬后再硅鞣制备的含铬硅鞣革的耐湿热稳定性、力学性能、柔软度和耐黄变等性能。结果表明,脱铬过程中,脱铬材料酸用量相同时,随着时间的延长,皮革收缩温度和铬含量均逐步下降,然后趋于稳定;酸用量较大时这种变化更明显。两种用量脱铬后制备的含铬硅鞣革的性能差异不大,收缩温度都较高,力学性能和柔软度较好,耐黄变性能好。硅鞣剂渗透性好,在革中分布较为均匀。

The mixture of oxalic acid and sulfuric acid was used as the material for the removal of chromium in wet blue,and the effect of acid dosage and treatment time on the shrinkage temperature and chromium content of the leather was compared and analyzed.On this basis,the silicon tanning technology based on the dechromed wet blue leather was studied.Specially,hydrothermal stability,mechanical property,softness and yellowing resistance of chrome-containing silicon tanned leather based on the dechromed crust leather were tested and compared.The results showed that,in the process of dechroming,for the same amount of acids,with the increase of time,the shrinkage temperature and the content of chromium of leather gradually decreased and tended to be stable.In particular,this change is more obvious when the amount of acid is larger.There is little difference between the properties of chrome-containing silicon tanned leather prepared with the proposed acid dosages,as well as the higher shrinkage temperature,the better mechanical properties and softness,and the better yellowing resistance were obtained.Silicon tanning agent has good penetration and the silicon is evenly distributed in the leather.