The temperature of the pickle and tanning liquors influences the strength of the leather fibre - it also influences the rate self-basifying agents dissolve. TFL recommend close adherence to published data, and strict process control.
To avoid damage to fibre structure by acid hydrolysis the temperature of pickling must be kept low, 20-25°C being a typical maximum temperature at commencement of pickle. In hot climates this must be controlled with coolers on water supply or ice additions. This low temperature also slows down the initial reactivity of the chrome tannage bath when adding self basifying agents early in the chrome tannage run. See CROMENO information. Where the temperature of the pickle has increased due to friction of running and may in hot climates be as high as 35-40°C, after 2 hours the goods should be cooled by ice or chrome added as soon as possible. The practice of standing overnight in very warm pickle liquors before chroming should be avoided if the physical properties of the finished leather are not to be compromised.