Solutions for Global Bisphenol Challenges

GG Organics Pvt. Ltd., has been providing technology, development and technical services to the leather industry for over decades and strives hard to put the customer and the environment foremost.

GG Organics is the first Indian company to provide solutions to the global leather industry for reducing the Bisphenol A, F, S, and AF content of synthetic retanning agents. BPA is not present in any of their retanning agents.

GG Organicshas developed phenol-based retanning agents with desired limits of bisphenol content by using an innovative process, technology and monomer chemistry. The leather treated with GG Organics' low bisphenol retanning syntans has physical and mechanical properties that are similar to regular phenol and sulphone syntans, resulting in high-quality leather.

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.

Bisphenol Restrictions:

Voluntary Restrictions by the brands

(Source:https://www.leatherworkinggroup.com/contentfiles/LWG-1161.pdf?v=1)

Customers	Bisphenol A	Bisphenol F	Bisphenol S
Kering	≤200 ppm	≤ 200 ppm	≤ 1.000 ppm
Chanel		Information	Information
Salvatore Ferragamo	≤ 1.000 ppm (adults) ≤ 20 ppm (Children)	≤ 1.000 ppm (adults) ≤ 20 ppm (children)	≤ 1.000 ppm (adults) ≤ 20 ppm (children)
Hermes	≤ 100 ppm	≤ 100 ppm	≤ 100 ppm
Prada	≤ 1.000 ppm	≤ 1.000 ppm	≤ 1.000 ppm
Burberry	≤ 1 on polycarbonateplastics

Why there is a demand for chemicals and leather with low bisphenol content?

Bisphenol and its derivatives are known endocrine descriptors that are harmful to both human health and the environment, as well as causing reproductive toxicity. Because of the adverse effects caused by Bisphenols, European Chemicals Agency (ECHA) and the EU Member States have started screening data on a large group of Bisphenols such as BPA, BPS,BPF, BPAF and their derivatives outset in 2020.

Regulations governing the use of Bisphenols are becoming more challenging for the leather industry, as the majority of synthetic retanning agents are phenol and sulphone based.

Though the limitation of bisphenol S in leather is expected to be implemented between 2024and 2026, manufacturers and brands have started asking for leather with less bisphenol without compromising product quality.

Due to that, there is an increasing demand for Bisphenol-free or low bisphenol leather and chemicals in the global leather market.

What is Bisphenol?

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

Types of Bisphenol

1. Bisphenol A (BPA)
2. Bisphenol AF (BPAF)
3. Bisphenol F (BPF)
4. Bisphenol S (BPS)

Bisphenol A (BPA)

Chemical Formula: C15H16O2
IUPAC Name: 4,4'-(propane-2,2-diyl) diphenol

BPA is an organic chemical synthesised by the condensation of phenol and aceton.All by- products of the BPA synthesis, including unreacted phenol, are toxic. An environmental profile associated with the production of BPA as a monomer is available from plastic manufacturers. Lab-scale yields up to 96% were reported for this process. A purity greater than 98% is required for most uses of BPA.

Health Impacts

Regulations:

In June 2017, BPA was identified as having endocrine disrupting properties for human healthby the Member State Committee of the European Chemicals Agency (ECHA) (ECHA, 2017).

Due to its properties as toxic for reproduction, BPA was already listed as a substance of veryhigh concern (SVHC) on the Candidate List under Regulation (EC) No 1907/2006 of the European Parliament and of the Council on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH).

Hazard Classification and Labelling

Danger! According to the harmonised classification and labelling (ATP09) approved by the European Union, this substance may damage fertility, causes serious eye damage, may causean allergic skin reaction and may cause respiratory irritation.

Additionally, the classification provided by companies to ECHA in REACH registrations identifies that this substance may damage fertility or the unborn child and is toxic to aquatic life with long-lasting effects.

Bisphenol AF (BPAF)

Chemical Formula: C15H10F6O2

IUPAC Name: 4,4′-(1,1,1,3,3,3-Hexafluoropropane-2,2- diyl)diphenol/ 4,4'-[2,2,2-trifluoro-1- (trifluoromethyl)ethylidene]diphenol

BPAF is a fluorinated organic compound that is a derivative of bisphenol A in which thetwo methyl groups are replaced with trifluoromethyl groups.

Hazard Classification and Labelling

Danger! According to the classification provided by companies to ECHA in REACH registrations this substance may damage fertility or the unborn child, is very toxic to aquatic life with long lasting effects, causes serious eye damage and may cause damage to organs through prolonged or repeated exposure.





Chemical Formula: C12H10O4S

IUPAC Name: 4,4'-sulphonyldiphenol

BPS is an organic compound with two phenolic functional groups are on either side ofa sulfonyl group. BPS differentiates from BPA by possessing a sulfone group (SO2) as the central linker of the molecule instead of a dimethylmethylene group (C(CH3)2).

BPS is the reaction product of two moles of phenol with one mole of sulfuric acid. Along with4’-4’ sulphonyl bisphenol, 2-2,2,4 isomers are also formed.

2 C6H5OH + H2SO4 → (C6H4OH)2SO2 + 2 H2O

BPS or its derivatives are used in the production of polyethersulfone, polysulfones and epoxyresins

Health Impacts:

Hazard Classification and Labelling

Danger! According to the classification provided by companies to ECHA in REACHregistrations this substance may damage fertility or the unborn child.

Other release to the environment of this substance is likely to occur from: indoor use in long-life materials with low release rate (e.g. flooring, furniture, toys, construction materials, curtains, foot-wear, leather products, paper and cardboard products, electronic equipment),outdoor use in long-life materials with low release rate (e.g. metal, wooden and plastic construction and building materials) and indoor use in long-life materials with high release rate (e.g. release from fabrics, textiles during washing, removal of indoor paints).

Bisphenol F

Chemical Formula: (HOC6H4)2CH2

IUPAC Name: 4,4′-dihydroxydiphenylmethane



BPF is an organic compound in which the two phenolic groups are linked bya methylene connecting group. The Bisphenol F, is prepared by condensation reaction of phenol and formaldehyde with a large excess of phenol under acidic conditions. It is also formed during condensation of phenolic syntans reactions. It is structurally relatedto bisphenol A, a popular and controversial plasticizer, as both belong to the category of molecules known as bisphenols.

Hazard Classification and Labelling

Danger! According to the classification provided by companies to ECHA in REACH registrations this substance may damage fertility or the unborn child, is very toxic to aquatic life with long lasting effects, causes serious eye damage and may cause damage to organs through prolonged or repeated exposure.

Relationship between Bisphenol and leather

Replacement syntans are also known as synthetic organic tanning agents. This replacement syntans were initially developed to replace vegetable tannins, resulting in leathers with good softness and fullness.

Replacement syntans are classified into several types, but they are primarily composed of formaldehyde condensates of phenolsulphonic or naphtholsulphonic acids. In addition, cresol, napthol and bisphenol are also used for the manufacturing process of replacement syntans.

In particular, Bisphenol S (dihydroxy diphenyl sulphone) is used as raw materials for the manufacturing of sulphone syntan. During the course of reaction, bisphenol F may also formed when phenol reacts with formaldehyde. In the leather industry, these phenol/sulphone syntans are primarily used for pretanning, tanning, retanning, and dyeing.

Sulphone syntans has very good water dispensability, permeability and absorbability, especially with excellent light fastness and yellowing resistance. These syntans has been developed as a potential retanning agent for the production of wet-white leathers.

Bisphenol S is mainly used as a primary tanning agent in the manufacturing of light fast whitesyntans, and can also be used for dye fixing on leather and textiles.

Advantage of replacement syntans over vegetable tannins

References:

1. https://www.hbm4eu.eu/hbm4eu-substances/bisphenols/
2. https://saferchemicals.org/get-the-facts/toxic-chemicals/bpa-bps/
3. https://sinlist.chemsec.org/chemical-groups/bisphenols/
4. https://www.millionmarker.com/the-science/chemical-glossary/bisphenol-s-bps
5. https://enveurope.springeropen.com/articles/10.1186/s12302-021-00586-9
6. https://journals.uc.edu/index.php/JALCA/article/view/1533/1039
7. Dihydroxy–diphenylsulphone and Salicylic Acid Derivatives in the Aftertreatment of Dyed Nylon M. Tomita,M. Tokitaka
8. Chemistry of Syntans and Their Influence on Leather Quality by Jochen Ammenn,* C. Huebsch, E. Schilling and B. Dannheim Automotive Leather, BASF SE, Ludwigshafen, Germany
9. https://www.chemicalbook.com/Article/Bisphenol-S-Chemical-properties-Uses.htm
10.https://www.reach-clp-biozid-helpdesk.de/EN/Home/German_propsal_restriction/BPA/BPA.html

For more information on the low bisphenol range of products, please contact

tech.support@ggorganics.co.in