What is Bisphenol?

Bisphenol is a synthetic organic compund containing 2 phenol groups (two hydroxyl phenyl groups) and it is used mainly for making plastics and resins.

Types of Bisphenol


  • Bisphenol A (BPA)

  • Bisphenol AF (BPAF)

  • Bisphenol B (BPB)

  • Bisphenol F (BPF)

  • Bisphenol S (BPS)

Aromatic Syntans

  • Receives much attention due to their advantages of filling property, dispersibility, and bleachability.

  • Well suited for all color shades and result in leathers with a better lightfastness, compared to leathers retanned with vegetable tannins.

  • Generally prepared through condensation, sulfonation, and other reactions by using phenol or naphthalane, formaldehyde, and concentrated sulfuric acid as raw materials.

  • Common compounds in aromatic syntans

  • Phenolic monomers such as phenol.

  • Phenol sulfonic acid

  • bisphenol S (dihydroxy diphenyl sulphone)

  • bisphenol F

  • These compounds are used as either starting materials or intermediate molecules formed during the manufacturing process.

  • Application of Bisphenols in leather Processing

  • In general, aromatic syntans are condensates of phenolsulfonic acid and/or phenol and/or dihydroxydiphenylsulfone (DHDPS or Bisphenol S) with formaldehyde where urea is optionally used.

  • Bisphenol S (dihydroxyl diphenyl sulphone) is used as raw materials for the manufacturing of sulphone syntans.

  • Depending upon the efficiency of the consideration process, a certain amount of phenolic monomers are left unreacted during the manufacturing process. This unreacted phenol may react with formaldehyde, resulting in the formation of bispenol F.

  • In the leather industry, these phenol/sulphone syntans are primarily used for pre-tanning, tanning, retanning and dyeing.

  • These unreacted phenolic monomers such as phenol, phenolsulfonic acid and bisphenol S/F that are present in the syntans, will be transferred to the leather during the (re)-tanning processes.

  • Minimizing the bisphenol content of leather with GG Organics synthetic tanning agents

  • GG Organics has developed phenol-based retanning agents with desired limits of bisphenol content by using an innovative process, technology and monomer chemistry.

  • BPA, BPB and BPAF are not present in any of our retanning agents

  • The real challenge is matching the properties of conventional syntans. We did this with our new range.

  • GG Organics' cutting-edge laboratory has been upgraded with advanced LC-MS testing equipment for identifying the concentration of bisphenol in retanning agents and leather. This would ensure an efficient delivery mechanism in the frontier areas of the leather industry.

  • All of our low bisphenol products are evaluated with LC-MS technology, and the results were below the limit proposed by BAuA and the major customers.


  • Safe Products from GG Organics (Completely Bisphenol Free)