Why does the car windshield feel oily on rainy days?
3 Answers
Car wax and dust can easily get trapped in these tiny pores, forming a contamination layer—the oily film layer, which is also the main reason why the front windshield often doesn't stay clean. Below is some relevant information: Windshield: Car windshields are generally made as a single large curved piece, with a certain curvature on all sides. This curved glass is a highly technical product, both in terms of the manufacturing process and the fitting during assembly, as it involves numerous factors such as vehicle model, strength, heat insulation, and installation. Function of the Windshield: Tempered glass refers to ordinary glass that has been quenched to create internal stresses, thereby strengthening the glass. When impacted and shattered, the glass breaks into small pieces with blunt edges, reducing the risk of injury to passengers.
When driving in the rain, the windshield feels slippery as if coated with oil, which is usually caused by oil film. Think about the exhaust emissions from traffic, industrial area smoke, and even tree sap that quietly accumulate on the glass surface. When it rains, water mixes with these contaminants to form a greasy film, causing water droplets to bead up and obstruct vision. My solution is to regularly use a dedicated glass cleaner to wipe the windshield until it shines. Worn-out wiper blades can also worsen the problem, so it's important to replace them promptly. Don’t underestimate this oily sensation—blurry vision at night can lead to serious accidents. Additionally, I recommend using a car cover when parking under trees to prevent sap buildup. During weekly car washes, focus on cleaning the glass to prevent accumulation. Also, adding an oil film remover to the windshield washer fluid is a simple and effective habit that ensures safer driving.
I think this issue is inseparable from environmental pollution. Pollutants in the air, such as vehicle exhaust and industrial emissions, contain oily particles that settle on the glass. When it rains, water mixes with these oils to form a greasy film that feels slippery. I care about the environment, so I use biodegradable cleaning products to avoid chemical residues. My personal habit is to drive less in congested areas to reduce exhaust adhesion. When cleaning, I use a soft cloth and clean water to regularly rinse the glass. Prevention is key—parking in areas with heavy roadside traffic makes oil film formation more likely. Wiping the glass before rain can help keep it safe. Rainwater is natural, but pollution turns it into a problem. I urge everyone to support green travel and reduce emissions. Clear car windows not only ensure driving safety but also lighten the burden on the planet, improving our mood. As a car owner, I share these tips hoping to help others deal with similar situations.
