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)
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)
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)