Acidic Buffering System for Dyeing and Acidifying
PERISTAL CSL is a liquid, phosphate-free, non-volatile buffer for pH adjustment of dyeing liquors as well as for neutralization of textiles. With PERISTAL CSL you can buffer a weakly acidic pH range between pH 4 and 6. The big advantage of PERISTAL CSL: The buffering system is not volatile. Thus, the adjusted low pH value remains stable even at higher temperatures during dyeing or other textile finishing processes. Furthermore, the buffer does not evaporate during drying or storing. With PERISTAL CSL you can adjust a constant, slightly acidic pH value on the textile goods. In this way, treated fabrics and ready-made garments meet the requirements of Standard 100 by OEKO-TEX®. In garment and textile finishing the addition of PERISTAL CSL during softening helps to reduce the risk of storage yellowing of white goods and pastel shades.
What is a Buffering System?
An acidic buffering system consists of a weak acid and its conjugated base or the respective salt. When adding an acid or a base – also called alkali or lye – the pH value of a buffered solution changes less than of an unbuffered system. Examples for acidic buffering systems are acetic acid/acetate or formic acid/formate. One disadvantage of both before-mentioned buffering systems is the volatility of the used acids. Acetic acid as well as formic acid are volatile and therefore evaporate easily which causes a pH shift of the buffered solution. There are also basic buffering systems which consist of weak bases and their conjugated acids or salts. Such alkaline buffers are used for buffering alkaline pH ranges.
Application of PERISTAL CSL
PERISTAL CSL is used as a non-volatile buffer for dyeing of polyester, polyamide or wool for the adjustment of stable acidic pH values between pH 4 and 6. The required pH of the dye baths is adjusted with PERISTAL CSL before the dyestuffs are added. For pH adjustment according to Standard 100 by OEKO-TEX® PERISTAL CSL is added to the final finishing or rinsing bath. In order to minimize storage yellowing PERISTAL CSL is used during softening.
Acidic Buffering Systems for Various Applications
Textilchemie Dr. Petry GmbH offers PERISTAL buffering systems and acid donors for various textile applications. Our consultants will be pleased to recommend you the suitable product for your technical application.
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