Meritxell Puigdemund, Area Manager at Delta Tecnic

The automotive market is accelerating in its quest for a zero polluting emissions scenario. Administrations, companies and society are increasingly aligned on this growing and expansive path, giving rise to two simultaneous revolutions: the transition to the electric combustion engine and the independent car.  

These transformations reflect the dramatic growth in sales and forecasts for electric cars. According to Bloomberg New Energy Finance (BNEF), by 2024, around 12% of new cars sold worldwide will be fully electric; by 2040, that figure will be more than 50%. The prediction is that the electric car will dominate sales by 2050. The data therefore confirms that manufacturers are going electric and that production processes need to keep pace.

Companies not only need to create quality products that are competitive, but they must also optimize their materials, formulations and manufacturing processes to make them faster and more efficient. Thus, automotive manufacturers require new materials and formulations, with higher precision and higher standards when insulating wiring. In cable production, there is a trend towards faster cable production, reduced insulation thicknesses and shorter extruder lengths. Thanks to these new, more technical materials, this is possible without compromising the result of the product or its colour homogeneity. 

Satisfying the technical needs of automotive cables requires perfect dispersion and excellent dilution, with low dosage levels, high production speed and high processability, i.e., better First Time Quality. Optimizing all these factors has a direct and positive impact on the final costs, which is very tempting for the rapidly evolving companies in the automotive industry.

Understanding the importance of automotive cable colours

Colours are an essential part of the cable industry. First, their colour coding allows each cable to be identified so that its circuits can be easily distinguished when building the hardness, making repairs or diagnosing problems. Since the colour must be identifiable for the lifetime of the vehicle, it is critical that there is colour durability in the cable. 

Then there is the challenge for colour masterbatches for cables, which is to dilute and fully incorporate the colour, unifying the polymer base with the individually separated pigment crystals at the right melting point; under very demanding production conditions, such as reduced extruder lengths, increased speed or the increased lightness required by the market – this is where new materials come into the picture. In addition, the colour concentrates must be compatible with the compounds used, have perfect dispersion and offer fast dilution to avoid sparks or other quality problems. 

Colour intensity is also a key factor. The simplest, but not the most cost-effective, way to manage colour deficiency is to increase the dosage.  For best cost-effectiveness, it is important to work with highly concentrated colour masterbatches with the appropriate pigments to achieve the right colour strength at the lowest possible dosage, aided by fast dilution.

New materials for an evolving market 

Thermal resistance, abrasion and aging are some of the challenges cable colouring faces. There is a need for more technical materials to insulate automotive wiring through new composite formulations. This is something that is gaining relevance for the electric car market, but especially for the autonomous car market, which requires high-strength materials with extreme precision. 

Fluoropolymers, as thermoplastics and elastomers, find wide use in automotive applications, due to their combination of high resistance to fuels, lubricants and elevated temperatures. Fluoropolymers can operate at ambient temperatures from -40°C to 200°C, with excellent resilience and UV transmission, providing high resistance to energy radiation and light weight; two key factors for electric car requirements. 

Silicone are also compounds currently in growing demand, useful in various types of automotive cables, such as batteries or lighting, and high-demand wiring. Silicone allow working with constant dielectric and dielectric properties of dimensional stability from -80 °C to 250 °C. In addition, they resist vibration and fire, produce low smoke emissions, and emit non-corrosive and non-toxic combustion gases. 

Conclusions 

The combination of high-performance, high-strength materials and colour masterbatches is an ideal approach to meet the demand for new materials or formulations with higher performance.  

At Delta Tecnic, we are specialized in offering high quality colour concentrates for the automotive industry with excellent dispersion and dilution properties, paying special attention to the reduction of sparks, colour regularity, pellet size and shape; all of this for the improvement of the production of vehicle wiring harnesses.