What causes the windshield to become blurred after using a degreaser?
4 Answers
The windshield, after prolonged exposure to sunlight, heavy rain, wind erosion, etc., develops a microscopically rough surface with numerous pores or pits on the surface. Various oily substances, car waxes, and dust from daily driving can easily adhere to this roughened windshield surface. Specific solutions are as follows: 1. Soap water: Use household soap water to scrub the windshield once, removing the actual oil film layer on the glass surface and washing away ordinary dust layers, which helps in further cleaning. 2. Hot soap water: Soak and wash with hot soap water. If regular cleaning doesn't suffice, then hot water should be used for soaking and cleaning. Hot water provides thermal energy to molecules, causing them to move more vigorously, which can break van der Waals forces and hydrogen bonds, ultimately removing the physical adsorption layer. 3. Use specialized cleaners: Scrub with a hydrochloric acid solution. Hydrochloric acid is a strong acid that can dissolve and decompose most organic or inorganic substances, including metal oxides, without affecting the glass. This is because the main component of glass, sodium silicate, is only soluble in hydrofluoric acid and strong bases.
That day, after using the newly purchased degreasing product, my rear windshield suddenly became blurry. Frustrated, I drove straight to the auto repair shop to ask the mechanic. He said the issue might lie in three aspects: First, the product itself could be of poor quality, as inferior cleaners contain overly abrasive particles that can scratch the glass. Second, incorrect application techniques, such as vigorously scrubbing sun-heated glass with a hard sponge or using circular motions that create spiral marks. Third, hidden issues on the glass surface, like aging film that becomes more bubbly after using the cleaner. The mechanic taught me how to identify the problem: observe the glass under sunlight at different angles—straight-line scratches indicate physical damage, while cloud-like smudges suggest chemical residue. He also recommended trying a glass polishing compound for repair first, and only consider replacing the glass if that fails. He advised buying a neutral cleaner for safety.
As a veteran driver with over a decade of experience driving older vehicles, I've encountered many cases of windshield hazing. There are primarily two types of streaks that appear after degreasing: one resembles a frosted effect, usually caused by residue from abrasive particles in cleaners; the other looks like oil diffusion, resulting from product residue mixing with water stains on the glass. Timely treatment is crucial. I prefer using a paste made from lemon juice and baking soda to gently wipe, which effectively dissolves residues. Remember three key lessons: always rinse off dust before cleaning to avoid scratches, follow the instructions for dwell time, and water-based wax products are easier to clean off. Next time you purchase, check the ingredient list to avoid products containing sulfuric or hydrofluoric acid.
A friend just finished removing oil film and found the glass was scratched. After investigating, we realized the root cause was water. In hard water areas, minerals from tap water can deposit during rinsing, combining with cleaners to form a crystalline film. This is especially true when using hot water for rinsing, as faster evaporation leaves more scale behind. It's recommended to switch to distilled or purified water for final rinsing, or use a 1:10 white vinegar solution for an additional wipe. Large temperature differences are also risky—using warm water to clean cold glass in winter can reveal micro-cracks on the surface. The most practical solution is to keep a microfiber cloth on hand, the mirror-grade type, specifically for final polishing.
