A better way to clean them is with water and  Marseille soap.  Rub the outdoor furniture well with a sponge and then rinse. Then dry the entire surface with a microfiber cloth.

But in addition to Marseille soap, you can also prepare a mixture of three parts vinegar and seven parts water and then proceed in the same way as with the soap. There are also specific products on the market to make outdoor furniture look like new again. They are real detergents that protect against the chemical reaction caused by sunlight.