This morning, my windshield was icy and frosty. I used a snow brush/ice scraper on it. I used the kind that has like teeth on it. I went to school, and came back out about 11:00 and noticed it all scratched up?? How can a ice scraper scraper scratch a windshield. My dad thinks the plastic just came off on the windshield, but I tried naptha and acetone and it didn't come off?? Help.