Why does Teflon coating make the iron "silky" and not stuck on clothes?

1. Characteristics of molecular structure
C-F bond stability——
Teflon is composed of carbon chains and fluorine atoms. Fluorine atoms are extremely electronegative, forming a tight electron cloud barrier that makes it difficult for other molecules to approach. The surface energy is only 18-25 mN/m,  and liquids and solids can hardly spread or adhere to its surface.

Non-polar surface——
The molecular structure is highly symmetrical and has no polar groups, so it cannot form hydrogen bonds or van der Waals force adsorption with the polar groups of clothing fibers.

2. Physical anti-stickiness
Smooth surface——
The sintered Teflon coating forms a dense and non-porous structure with a surface roughness as low as 0.05μm, which is lower than the diameter of the fabric fiber (cotton fiber is about 10-20μm), reducing the possibility of mechanical interlocking. In the spraying process, nano-scale PTFE particles melt and level, eliminating microscopic bumps. The contact angle of the coating is greater than 110°, and water and oil stains roll off in a spherical shape, while taking away dust and fiber debris to keep the surface clean.

3. High temperature stability
The Teflon iron soleplate has a continuous temperature resistance of 260°C and a short-term temperature resistance of 300°C, which completely covers the working temperature range of the iron (usually 120-230°C). The molecular chain does not decompose or oxidize at high temperatures, avoiding sticky residues caused by coating deterioration.

4. Low sliding resistance
The surface friction coefficient of the Teflon iron soleplate is only 0.05-0.15 (close to the ice surface), and clothes only need a very small thrust to slide when ironing. The fluorine atomic layer forms a transfer film during friction, further reducing direct contact with clothes.

5. Combination of coating and substrate
The substrate (such as aluminum alloy) needs to be treated by sandblasting, degreasing, chemical etching, etc. to increase the surface area and active groups and improve adhesion. The primer of the Teflon iron soleplate is added with polyamide-imide (PAI) primer, which is bonded to the metal substrate through chemical bonds to prevent the coating from peeling off during high-temperature use.