Gorilla Brand makes several kinds of glues, including its regular polyurethane glue, known as Gorilla Glue; a super glue (a cyanoacrylate glue) and an epoxy glue. Valued for their strong adhesion, these glues adhere to most surfaces; however, Gorilla glues do not cling as tightly to glass as they do to more porous surfaces, such as wood or plastic. Sometimes these glues can be carefully scraped off. Usually, you'll also need to use an adhesive remover--this will help soften the glue and break the bond between the surface and the adhesive.
Acetone (fingernail polish remover) helps soften Gorilla super glue and Gorilla epoxy glue, making these glues easier to remove from surfaces including glass. You can also try commercial epoxy, cyanoacrylate, or polyurethane adhesive removal products--not just any adhesive remover will do, so make sure the product states they are suitable for these kinds of glues. Examples include Soy-It polyurethane stripper, which claims to remove polyurethane, epoxies and other difficult adhesives and Super Glue Remover. You'll find selections of adhesive removers at hardware stores and similar retail stores.
Strong adhesive removers work chemically to soften adhesive and break the bond between the adhesive and the surface. The remover begins working immediately when applied, but it can take several minutes to several hours before the adhesive is ready to be removed.
Adhesive removers, used in conjunction with manual removal methods, are easy for almost anyone to use. Scraping the glue off without using these is often impossible--furthermore, you are more likely to scratch or break the glass using scraping methods alone.
Wear protective rubber gloves when working with adhesives or adhesive removers. After applying acetone or another adhesive remover with a cotton swab (or with the applicator, if using a commercial adhesive remover), use a plastic scraper or a razor blade to scrape the glue off the glass. You will also need a soft cloth and water to remove the acetone residue.
Acetone is very flammable--fumes may ignite if you use this around open flame, including pilot lights. In addition, keep skin exposure to acetone to a minimum. Wear gloves or wash your hands after using this substance. Avoid breathing acetone fumes--keep the area you are working in well-ventilated. Many other adhesive removers are also flammable. Always read the label before using.