What is Halogen :
Group VIIA in the periodic table of non-metal elements including Fluorine, Chlorine, Bromine, Iodine and Astatine. Since Astatine is a radioactive element, halogens are typically only referring to Fluorine (F), Chlorine (Cl), Bromine (Br) and Iodine (I).

Restriction on Halogens Free according to IEC 61249-2-21 :
Substance restrictions for halogen-free products and components
Substance	Permissible Limit (by weight)
Chlorine (Cl)	900ppm (0.09%)
Bromine (Br)	900ppm (0.09%)
Total Concentration of Chlorine(Cl) + Bromine (Br)	1500ppm (0.15%)

The present invention relates generally to electrical insulating films and tapes for use in various applications, such as automotive applications. The present invention further relates to electrical insulating films and tapes, including halogen-free electrical insulating films and tapes, which meet rigorous industry standards for flame retardancy, weatherability, thickness, tensile strength, elongation, dielectric strength, adhesion strength, moisture absorption, temperature resistance, deformation, longevity, and/or conductor corrosion

P.LEO follows the restriction of Halogen Free from International Electrotechnical Commission (IEC) in their tapes production. Although existing halogen-free electrical insulating films and tapes have increased the knowledge base, further improvements are needed that will yield halogen-free electrical insulating films and tapes that meet or exceed the flame retardancy and mechanical properties of halogen-containing electrical insulating films and tapes. The present invention meets this challenge. To supply a tape that includes a halogen-free backing comprising a polymeric material; a flame retardant; and a coupling agent; and an adhesive layer located on a surface of the backing. The tape is flame retardant tested according to Section 4 of Underwriters Laboratories UL 510, Seventh Edition. P. Leo products use their proprietary halogen-free, high temperature, modified adhesive. e.g. 1K063 Kapton Tape with silicone adhesive, 1K220 Polyimide Tape with Silicone Adhesive, 1K06A Polyimide Tape with acrylic adhesive, 1K7177 Kapton with Acrylic adhesive, 1PEN2 Polyethylene naphthalate (PEN) film Tape with Acrylic adhesive , 1P802 Polyester Film with acrylic adhesive, 1P833 (assorted color) and 1P801HF (yellow color) are polyester tape with flame Retardant approval according to UL 510; 1PFRS is make by Polyethylene Terephthalate film with Flame Class VTM-0  with UL approval tested according to UL510 and meet to RoHs requirement and Halogen Free testing according to BS EN14582:2007.