LANXESS Launches Witcobond-Branded High-Performance Polyurethane Dispersions

Growing demand from industry for sustainable coatings and adhesive solutions has driven the shift from solvent-based to water-based systems in recent years. More than 40 years ago, Witcobond® polyurethane dispersions (PUD) were developed to help customers comply with increasingly stringent regulations on volatile organic content (VOC) while simultaneously developing suitable solutions. In addition, Witcobond® product development work has included specialized efforts tailored to specific application needs to develop high-performance and high-solids products. Today, Witcobond® branded polyurethane dispersions offer diversity, performance, innovation and specific advantages to users across many different sectors.

Advantages of Witcobond® PUD

• Portfolio with strong performance at high solids levels, • Water-based blocked crosslinkers for 1K and 2K oven systems, • Over 40 years of experience and customization capability for applications, • High quality and product consistency. Formulators of water-based coating systems can choose from a wide range of Witcobond® polyurethane dispersions. LANXESS offers ester and ether types as well as anionic, nonionic and cationic grades. With Witcobond® products, it is possible to provide variations in final coating properties such as hardness, flexibility, toughness and chemical resistance.

Matte Surface Appearance with Witcobond 391-64

Witcobond® polyurethane dispersions can be crosslinked with various agents to further improve chemical resistance, coating adhesion and durability. LANXESS's Trixene® Aqua product group contains water-dispersed latent crosslinkers and adhesion promoters for formulating 1K or 2K oven systems. When heated, these multifunctional blocked isocyanates begin to crosslink with complementary functional groups on the coating and substrate.

Key Characteristics

• Solids content ranges from 30 to 60 percent by weight, • Offers grades free of auxiliary solvents and surfactants for optimization, • Meets HS&E requirements, • Special grades for specific coating needs (e.g., matte surfaces or soft touch), • Shows compatibility with a variety of aqueous binders such as acrylic dispersions, • Compatible with pigments, matting agents, flame retardants and other additives. Witcobond® Polyurethane Dispersions Address Specialized Applications Fiber Sizing and Composites LANXESS polyurethane dispersions are widely used in the fiber sizing industry and can be adapted for new requirements. They ensure superior adhesion of filaments in fiber and composite processing and deliver exceptional physical properties in final applications. Witcobond® 374-13 is a polyester-based polyurethane dispersion commonly used as a film-forming agent in glass sizing recipes. It provides excellent integrity for chopped yarn production and good adhesion to various thermoplastic and thermoset matrices. Adhesion between matrix and fiber can be further improved using blocked isocyanate technology. Special polyurethane dispersions with blocking groups in the polymer backbone can be produced or additives such as Trixene® Aqua BI 201 can be added to the standard sizing formulation.

Soft-Touch Coatings

Soft grades such as Witcobond® 374-13 can be incorporated into coating formulations that modify the haptics of normally hard surfaces. Such coatings provide, for example, improved aesthetics for automotive interiors and electronic components.

Coating Hard Surfaces

Alternatively, hard products such as Witcobond® 781 and Witcobond® 45766 can be used in durable, chemically resistant 1K and 2K systems applied to hard surfaces such as wood, metals, glass, plastic, concrete and walls.

Textile Processing

Water-based polyurethane dispersions such as Witcobond® 363-02 and Witcobond® 737 are widely used in textile processing. Typical applications include fully waterproof and weather-resistant coatings, back coatings, lamination adhesives, pigment binders used in textile printing and invisible surface finishes on yarns and fibers. Other functional textile uses include protective coatings on webbing, rope, braids, optical fibers and filament yarns.   Urethane coatings require abrasion, chemical and UV resistance where LANXESS can offer a range of solutions. LANXESS has a specialized polyurethane dispersion laboratory in Latina, Italy that can meet market needs in various coating and adhesive applications. The experienced technical team has the capability to conduct analytical studies, formulation development and synthesis of new products with high levels of technical differentiation. With the Witcobond® product group, LANXESS supports users in a wide range of applications including glass fiber sizing, plastic, glass and metal surfaces, coatings and textile finishing. The growing demand for VOC-free and low carbon footprint materials and increasing regulatory pressure on restricted chemicals has enabled LANXESS's applied research into water-based technologies to offer Witcobond® users greener technologies and chemistry. Ece Okçu Sales Manager, C.A.S.E. PU Kimsel