p-Toluenesulfonic acid monohydrate

p-Toluenesulfonic acid monohydrate (CAS 6192-52-5), commonly known as tosic acid or TsOH, is a strong organic acid supplied as a monohydrate form. It carries no E-code designation and is traded under abbreviations including pTSA and PTSA. It is registered under REACH and assigned EC number 612-715-0.

In coatings and adhesives, pTSA functions as an acid catalyst to initiate and accelerate curing reactions in melamine-formaldehyde and epoxy resin systems, reducing cure times at lower temperatures. In pharmaceutical manufacturing, it serves as a counterion in salt formation, improving the solubility and stability of active compounds. Textile processors also apply it to control bath pH during dyeing operations.

This material is available in technical and pharmaceutical-grade specifications, with compliance to Ph.Eur. standards for regulated applications. It is supplied in solid crystalline form, typically packaged in 25 kg bags or fiber drums. Sourcing documentation including SDS and REACH compliance declarations is available on request.