Durable coatings and optical bonding on visors, sensor windows and rugged displays

Industry: Helmets and visors, vision and sensor systems, rugged displays for vehicles and handheld equipment

Technology: Atmospheric plasma (PlasmaTEC-X), corona treatment (RotoTEC-X) and vacuum plasma (VacuTEC)

Anti-fog, hard and anti-reflective coatings on visors and sensor windows must survive sand, cleaning and temperature shock. On optical parts, a coating that peels or a trace of residue means a scrapped part. Plasma and corona treatment prepare the surface without contact or chemical residue, helping coatings and optical adhesives bond reliably while keeping the optics clear.

The challenge

Soldiers, pilots and vehicle crews depend on what they can see through. Visors, goggles, sensor windows, camera covers and display cover glass are typically made from polycarbonate, acrylic or glass. They are coated for scratch resistance, anti-fog, anti-reflection or filtering, and displays are often optically bonded to improve readability in sunlight.

All these layers depend on adhesion to a surface that must also be optically perfect. Molding release agents, plasticizer migration, fingerprints and dust from handling all reduce adhesion. In the field, coatings that are poorly anchored crack, craze or peel when exposed to abrasion, repeated cleaning, humidity and rapid temperature change.

In optically bonded displays, poor adhesion shows up as bubbles, delamination or haze at the edges. Each of these makes a display harder to read or forces a costly rework.

Why conventional preparation falls short

  • Solvent cleaning can cause stress cracking in polycarbonate and leave streaks or residues.
  • Manual wiping adds particles and scratches and is not repeatable.
  • Primers and adhesion promoters add a layer that must itself be optically clean and uniform.
  • Heat-based methods risk distorting thin, precise optical parts.

The solution

Plasma treatment cleans and activates the surface in one dry, non-contact step. It removes thin organic films and raises the surface energy, so lacquers, hardcoats, anti-fog layers and optical adhesives wet evenly and anchor reliably. The treatment leaves no residue and causes only a small temperature rise, helping protect heat-sensitive optical plastics.

For visors and larger parts that move on a conveyor or are handled by a robot, atmospheric plasma can treat the surface immediately before coating. For suitable parts and materials, Tantec’s RotoTEC-X corona treatment can also be used as an inline surface treatment before coating. The right process depends on the material, part geometry and coating.

For lenses, small windows and complex parts, vacuum plasma treats full batches uniformly on all sides. This can suit parts that are coated on both faces.

Before optical bonding, the cover glass and display surface can be plasma treated so the optically clear adhesive wets fully. That reduces the risk of trapped air and edge delamination.

How it fits into production

  1. Trials on optical parts. The customer’s parts and coatings are treated in Tantec’s laboratory, followed by adhesion and visual evaluation.
  2. Choice of technology. Inline atmospheric plasma or RotoTEC-X corona treatment before dip, spray or flow coating, or batch vacuum plasma for small and double-sided parts. Suitability depends on the part and process.
  3. Integration. The treatment is placed in or next to the clean area, as close to coating or bonding as possible.
  4. Verification. Surface energy is checked during setup and routinely, supporting a documented and repeatable coating process.

Why Tantec

  • Atmospheric plasma, corona and vacuum plasma, so the process can be matched to part size, geometry and whether one or both sides are coated.
  • Gentle, residue-free treatment suited to suitable optical plastics and glass applications.
  • Experience with coating adhesion in demanding industries such as medical devices, electronics and aerospace.
  • Laboratory testing on the customer’s own optical parts before investment.
  • Standard machines and custom solutions that fit coating lines and clean-room environments.

Is this your challenge?

If your coatings peel or craze in testing, or your optically bonded displays show bubbles or edge delamination, send us sample parts. We will treat them in our laboratory and show you what an activated surface can do for adhesion.