Bangladesh Leather Industry-Step towards APEO free Leather Production

Bangladesh Leather Sector At present leather sector accounts for 3-4 per cent of total export earnings. Of the total 214 tanneries in the country the majority are wet blue producers. Hardly 45 per cent of the total hides and skins is now processed into finished leather -- 18 per cent low grade for local consumption and 27 per cent for export either in the form of finished leather or leather products. Only a few tanneries are capable of producing export quality finished leather for export. There are about 15 export oriented shoe manufacturing units located mostly in and around Dhaka city. There are more than 2000 shoe making units supplying the domestic market. Leather and leather products have the potential to make a major contribution to export earnings and to the economic development of the country. One of the major constraints of export leather products to European market is strict regulation on hazardous chemicals. So, the aim of this article is to given a flashback to the use Alkylphenol Ethoxlates in leather production and help them to find APEO free leather auxiliaries.

Application of APEOs in General

Alkylphenol ethoxylates, APEO for short, are nonionic surfactants. They differ from cationic and anionic surfactants in that their performance is not affected by the presence of electrolytes, and this allows them to be employed over a wide pH range. It is manufactured by causing alkylphenol to react with ethylene oxide. The length of the hydrophobic alkyl chain and the hydrophilic polyglycol chain can be

varied in order to adapt them to a wide range of applications. They are highly effective wetting agents and emulsifiers and they can be employed in all situations in which hydrophilic and hydrophobic substances have to be brought together. Their applications range from detergents and cleaners through to textile auxiliaries, paper auxiliaries and pesticide formulations. The aim of this article is to given an given regarding the use of APEOs in leather industry and

Applications for APEO in the leather industry?

Products that contain alkylphenol ethoxylates can be used in the leather industry in all applications in which hydrophobic substances such as fats, oils or waxes have to be emulsified in aqueous media. They can be employed in finishing auxiliaries and, to a lesser extent, in fatliquors and water repellents. However, their main application in the leather industry is to remove the natural fat from the skin in the beam house on account of their excellent surface activity.

The natural fat contained in the skin has to be removed as thoroughly as possible for high-quality leather to be obtained. The penetration and distribution of the chemicals that are applied to the leather later on in the process can be affected if the fat is not removed, and this is visible in the finished leather in the form of greasy spots and stains.

Up until now, the most common practice has been to degrease skins in water with surfactants such as NPEO or fatty alcohol ethoxylates. Nonylphenol ethoxylates have been employed as degreasing agents on account of their better performance and their superior cost effectiveness.

After the leather has been tanned, the next step is to replace the fat that has been removed from the leather in order to make it soft and supple. Natural and synthetic waxes and oils can be used in fat liquors, depending on the type of effect that is required.

Modern water repellents generally contain polysiloxanes. Both of these groups of products are normally supplied in the form of emulsions, and alkylphenol ethoxylates are still used to emulsify and stabilize emulsions of this type. The majority of fat liquors and water repellents are self-emulsifying to some extent. The fat contained in fat liquors is treated by a variety of chemical reactions such as sulfation, sulfonation or phosphation in order to insert hydrophilic groups into the hydrophobic fat. This increases its affinity for the leather and also makes it self-emulsifying. However, additional emulsifiers are often added to improve the stability of emulsions and to allow them to withstand long periods in storage and variations in temperature etc.

Safer Alternatives

Alternatives are available in the market, most of renowned chemical manufacture came up with alternative chemistry, just as an example is Esopen OE by BASF; the technical data sheet can be downloaded from-

http://www.prismadye.com/Files/TDS/EN/EUSAPON%20OE_EN.pdf