Leather chemicals: catalysts for advancement18 July 2018
What’s new in the chemicals sector? Leather International takes its annual foray into highlighting chemical advancements within the industry, including updates on functionality, the latest products and state-of-the-art applications.
In October 2017, Stahl announced its acquisition of BASF’s leather chemicals business, which is part of BASF Performance Chemicals division. At the time, CEO Huub van Beijeren, said, “The chemical industry is changing at a rapid pace. To stay ahead of the game, we need a certain [amount] to invest in the two key topics in our industry: next-generation innovations and sustainability.”
There is no doubt that companies focused on leather chemicals have to remain vigilant, considering the demand and unpredictability of the market. In order to achieve success in today’s climate, it is imperative to align the entire supply chain along a course of increased transparency to achieve greater influence within the industry, as well as persevere with initiatives that help to eliminate restricted substances, reduce greenhouse gases and water, and use more natural raw materials.
For example, The Zero Discharge of Hazardous Chemicals (ZDHC) Roadmap to Zero programme takes a holistic approach to reducing the use of hazardous substances in the global textile, leather and footwear value chain. As a result of its diligence, the uptake in membership is steadily increasing.
However, bad press continues and consumer appetites are shifting to alternative materials. Due to the rising cost of raw materials, price increases have also been reflected in the chemicals market.
“In the course of the continuous review of our raw material exposures, we see rising costs in the area of chrome ore, basic chemicals and solvents and silicones used for the production of chrome and leather chemicals,” said Thomas Brackemeyer, head of the organic leather chemicals business line at Lanxess, in a statement. “For this reason, we take this second step in 2018 to adjust the prices for selected products.”
To maintain a high standard of quality, which is synonymous with transparency and sustainability, it remains necessary to make adjustments, in order to survive in the long term. With this in mind, Leather International highlights some of the newest breakthrough products from some of the biggest leather chemicals companies in the world, such as speciality chemicals company Lanxess.
The company’s leather business unit is a leading provider of system solutions for the industry, from chemicals for all stages of leather production to intensive on-site technical support. The latest generation of products provides unique tanning, retanning and finishing results. Lanxess is therefore bringing economic interests, ecological soundness and consumer safety requirements to the fore.
This versatile enzymatic ammonia-free bating product can be used for a broad range of applications. Practical trials revealed a good opening up of the grain layer, without sacrificing its tightness. As a result, it has a good inner softness and uniform grain break.
Due to the early addition of chrometanning salt, Blancorol reduces the hydrolysis of collagen in a pickle. This improves its quality, especially in hot conditions. In addition, it has the advantage of cutting the salt required in the pickle and chrome-tanning salts. Trials showed an improved chrome distribution in the cross section of wet-blue that had not been split.
Applied in conjunction with Levotan W, this new patent-filed polymer helps attain the highest dynamic and static waterproof requirements. It can be used to produce significantly firmer leather types for high-specification leather articles. In addition to providing a drier surface feel, which is ideal for producing nubuck with uniform dyeing, it can also be applied as a high-performance softening agent with excellent light fastness, grain tightness and filling. Levotan is anionic and compatible with the usual anionic retanning products.
Baygenal Black QX
This new anionic powder dyestuff has been specially developed for drum dyeing with specific colour tones, and has the required jetness suitable for all leather types. Its solubility, exhaustion and penetration capabilities are solid, as is its uniform tone-in-tone build-up on the flesh and grain sides. For the sector automotive, the product has adequate fastness properties, compared with commonly used black dyes used for this type of application.
Baygenal Black QX CONC
As a new highly concentrated, black, anionic powder dyestuff version of Baygenal Black QX, this has been developed for drum dyeing, but with neutral colour tone and a high degree of jetness.
This emulsion is a new-generation, soft acrylic base-coat binder that has great coverage on full and corrected-grain leather types. Furthermore, the product provides low Tg, excellent print retention and cut-through resistance with a low-surface tack.
EUDERM HSN 60
This formaldehyde-free acrylic binder is special for its high concentration, making it especially suitable for use in transfer coating for thicker layers, such as the adhesive coat. It imparts coverage and filling, adhesion-flex performance and hydrolysis resistance.
AQUADERM XL DI 90 and AQUADERM XL 100
Lanxess’s latest developments in the field of polyisocyanate cross-linking agents. The main purpose of these products is the further reduction of volatile organic compounds (VOCs) and smell, particularly in automotive applications that are very much driven by these two topics.
EUDERM X-tra Wax PW
A water-based wax for very strong burnishing effects that can be applied on chrome and vegetable-tanned crust. This particular effect can be achieved easily with polishing.
EUDERM X-tra Wax WB 2
‘WB’ stands for white break. This product is commonly used for fashion applications, where an item requires whitening effects that have a beautiful contrast to the darker background of the finish applied underneath.
EUDERM X-tra Wax TG
This synthetic polyethylene polishing wax is great for natural high-gloss finishes, as well as providing glossy tips for finished articles that are used in aqueous-base formulations. In binder-containing base coats, the product reduces the tackiness of a finish and enhances dry-rub fastness properties.
EUDERM X-tra Wax Pull-Up
Highly regarded for the manufacturing of pull-up articles, this product can be applied on full and corrected-grain leather, either directly, on the crust or on top of standard base coats. It is even possible to achieve pull-up effects on pigmented leather, thanks to its special composition.
EUDERM X-tra Prebottom NL
To improve the surface quality of leather, this pre-bottom has been especially designed for upgrading small grain-side defects on elegant leather articles, while maintaining their natural and soft characteristics after finishing.
EUDERM Prebottom NB
A non-ionic upgrading product made of synthetic fillers and waxes that can be combined with anionic or cationic products, which provide a wide range of applications for natural shoe-upper and bag leather. Furthermore, EUDERM is polishable and helps to level the penetration of subsequent coats.
EUDERM Wax NW
This non-ionic and synthetic wax and oil emulsion is used for applications that require having a nice gloss, transparency and a natural touch. As with other nonionic products, EUDERM Wax NW can also be combined with anionic and cationic products.
EUDERM Wax 2058
Formulated from natural waxes, this emulsion is perfect for articles with medium to strong pull-up effects. By combining the product with suitable pull-up oils, users can achieve stronger and desirable effects.
BAYSIN X-tra Luster HTC
In base and top-coat formulations, this hard and transparent protein binder gives leather a more natural appearance. The product’s other advantages are providing a pleasant, dry surface touch, as well as a high gloss.
BAYDERM X-tra GLOSS
This aliphatic polyurethane dispersion top-coat binder provides high-gloss finishes, such as patent imitation. It is commonly used as a sole binder, imparting a glossiness and transparency with good physical properties. The product can be cross-linked and is applied by spraying, or reverse-roll or curtain coating.
Zschimmer & Schwarz
In the leather industry, the company’s chemical auxiliaries are used in the manufacturing process to maintain the materials’ unique properties, including softness and robustness.
A special polymeric auxiliary with outstanding dispersing action on retanning and fatliquoring agents, which simplifies the control and optimisation of wet-end processes.
With regard to waterproofing, Novaltan DPA remarkably increases hydrophobing values, especially when combined with the Ombrellon range. The product is also suitable for automotive leather articles because of its excellent light and fogging fastness.
This liquid-synthetic tanning agent is suitable for the production of leather and fur articles that require softness and fullness. Leathers treated with Dolatan have a bright surface, making it the right choice for white, pastel and other brilliant shades. This salt-free product meets tough demands, especially for automotive leather production.
Characterised by its low VOC and FOG values, PROVOL LX is suitable for all automotive-upholstery leather that requires outstanding fogging behaviour, good heat and light fastness, as well as a high level of softness. Thanks to its concentrated composition, its use is economical, and guarantees a good penetration, distribution and fixation into the leather.
PRINOL Z 8
A polymer-based fatliquoring agent with brilliant electrolyte stability and softness. It has been developed as an alternative to sulphited fish oil and is suited to the fatliquoring of automotive leather in the pickle, chrome-tanning and retanning process. Thanks to its excellent fibre-lubrification, final articles show advanced physical properties. Prinol Z 8 exhibits good resistance against light and heat-induced yellowing, and distinguishes itself by having low emission values.
Groundbreaking wastewater technology from China
BIOSK’s wastewater-reusing technology focuses on the sustainable development of tanneries, and went into commercial production in 2010. Despite initial hesitation from the market, it is now relied on by the industry, as evidenced by the granting of Chinese, US, Australian and New Zealand patents. Today, the company’s technology is starting to gain more recognition, and is gradually being accepted by tanners around the world.
BIOSK’s research and development team has been boosted by joining forces with Chinese universities that are famous for conducting scientific research on leather production, including Qilu University of Technology, Shanxi University and Sichuan University. By doing so, the company has verified the advantages of the recycling process; for example, one professor from Shanxi found recycling wastewater produces a higher content of positive-chromium complex than the conventional process, thus providing a theoretical basis for improving leather fullness and increasing shrinkage temperature in the wastewater-reusing process.
Initially, only one large tannery adopted this technology. Today, commercial implementation has grown substantially, with many tanneries integrating the technology into industrial production. The species of rawhide processed during production has also increased from one to multiple types.
Take Huanghua Defu Leather Products in Hebei Province, for example. This tannery has a history of providing high-end finished leathers. Its main raw material used in production is the milk-drinking calfskin, and the physical indexes of the finished leathers produced by BIOSK’s technology meet a range of customers’ requirements. This recognition enables BIOSK to help more tanners update their traditional methods.