What Causes Interior Windshield Haze. Person blocking out the sun from windshield

What Causes Interior Windshield Haze?

Interior windshield haze, often caused by plasticizer migration, can occur due to various factors. Plasticizers are additives used in the manufacturing of plastics to impart flexibility and durability. Over time, these plasticizers can migrate from the materials they're embedded in, such as dashboard or interior trim plastics, and deposit onto the windshield due to heat, sunlight, and other environmental conditions.

Here's how it typically happens:

  1. Heat and Sunlight Exposure: High temperatures, especially in regions with intense sunlight, accelerate the process of plasticizer migration. When a car is parked in the sun, the heat causes the plasticizers to vaporize and migrate to cooler surfaces, such as the windshield.
  2. Aging Materials: As the vehicle ages, the materials containing plasticizers begin to degrade, releasing more plasticizers into the surrounding environment. This increases the likelihood of haze formation as these chemicals are released from the dashboard and trapped on the interior windshield.
  3. Poor Ventilation: Limited airflow inside the car can exacerbate the buildup of plasticizer vapors.
  4. Chemical Reactions: Chemical reactions between the plasticizers and other substances present in the car's interior, such as cleaners, air fresheners, or cigarette smoke, can also contribute to haze formation.

Sunlight hitting haze on the interior windshield caused by plasticizer migration can pose several driving dangers:

  1. Glare: Haze on the interior windshield can scatter sunlight, creating glare that reduces visibility. Glare makes it difficult to see the road ahead, traffic signals, other vehicles, and even pedestrians, thereby increasing the risk of accidents, particularly during dawn, dusk, or when driving directly into the sun.
  2. Distraction: Sunlight reflecting off the haze can be distracting, drawing the driver's attention away from the road. Distraction, even for a split second, can lead to delayed reaction times and errors in judgment, increasing the likelihood of collisions.
  3. Reduced Contrast: Haze can reduce the contrast of objects outside the vehicle, such as road signs, pedestrians, and obstacles. Reduced contrast makes it harder to distinguish important details, potentially causing drivers to miss critical information and increasing the risk of accidents.
  4. Impaired Night Vision: Haze on the interior windshield can worsen nighttime visibility by scattering light from oncoming vehicles, streetlights, and other sources. This can make it challenging to see clearly in low-light conditions, hindering the driver's ability to react to hazards on the road.
  5. Increased Glare from Oncoming Vehicles: Haze on the interior windshield can amplify glare from oncoming vehicles' headlights, particularly if the haze contains residue from cleaning products or other contaminants. Increased glare from oncoming vehicles can temporarily blind drivers, making it difficult to see the road and potential hazards.

To mitigate these dangers, it's essential to keep the interior of the windshield clean and free from haze or residue. The inShield® Cleaning Combo Kit was designed with this in mind. The patented design of inShield Wiper® allows it to slide onto the BACK of your hand, making it comfortable and easy to keep your interior windshield free of haze. Spraying a light misting of inShield Washer® onto the microfiber pad before using it cuts through the haze leaving a cleaner windshield and resulting in the ability to see the road clearer. This dangerous haze reappears about every 10 days which is why inShield Wiper® was designed to store in your car door pocket, so it is always within fingertip reach.

Want to know the best way to clean your interior windshield?

Read our blog Clear Vision Ahead: Why the inShield® Combo Cleaning Kit is the Ultimate Cleaning Solution for Interior Windshield Cleaning!

Back to blog