Pigments for Exterior Pavement Coatings

Color is everywhere. Color is in natural substances as well as manmade objects. In nature, the color is vibrant but fleeting. Technology has provided ways to match the vibrant color of nature but with longer lasting color. Organic and inorganic pigments are used in many plastic, coatings, and ink applications to replicate the color palette of nature.

Color is everywhere – even right below our feet. Color is used in road marking paints to infer driver directions, safety or merely to attract attention. Think of bike or bus lanes, handicap parking spaces, EV charging stations or the well-known yellow lines for lane identification. Since road marking paints are designed to convey messages, the color of the paint is critical to help deliver the message. Traffic paint, although singularly named, are really a collection of coatings for exterior pavement applications like parking lots, tennis and basketball courts, sidewalks and of course roadways.

Road marking paints are typically either air dry or thermoset in technology. Both application requirements and regions can dictate which type of technology is required. Thermal cure or “Hot melt” being the more specific technology is typically used in higher temperature regions where other coating systems may dry or cure too quickly. This technology is more permanent resulting in a longer life. In addition, thermal cure is used in regions where there is no concern for the thicker paint to be scraped by snow plows.

Colorants for road marking applications must exhibit good opacity, bright shades, and easily dispersed to be suitable for either hot melt or thermoset chemistries. Hot melt coatings have an additional requirement of a higher heat stability – they need to be able to withstand ~200⁰ C for 1-2 hours. This requirement points towards the high-performance pigments (HPP) which can withstand this type of heat profile without color change. In addition, HPP’s will also provide higher weather resistance for these types of coatings which can extend the life of the road marking. When selecting colorants for pavement coatings a few key decisions are required. The question flow diagram below can help the formulator select the pigmentation required to meeting the formulation and application needs.

Sudarshan has a full portfolio of pigments to meet all the required color spaces for exterior pavement coatings as well as for both hot melt and air dry formulations. Below is a suggested list of pigments.

  • Air Dry Cure
    • PY74 - Sudafast Yellow 127 or 130C
    • PY83 - Sudafast Yellow 134
    • PY139 – Sudaperm Yellow 2935P
    • PY65 - Sudacolor Yellow 119C or 118
  • Hot Melt
    • PY83 - Sudafast Yellow 134
  • Air Dry and Hot Melt
    • PO36 - Sudaperm Orange 2915C
  • Air Dry Cure
    • PR3 - Sudacolor Red 415 or 417
    • PR112 – Sudafast Red 336 or 337
    • PR170 - Sudaperm Red 2963C or 2967C
  • Hot Melt
    • PR170 – Sudaperm Red 2963K or 2967K
  • Air Dry and Hot Melt
    • PB15:3 - Sudafast Blue 2778C, 2784 or 2785
  • Air Dry and Hot Melt
    • PG7 - Sudafast Green 2727C

Please connect with your Sudarshan representative or contact Sudarshan at contact@sudarshan.com for more information.