Cotton filter cloth will swell in alkali solutions to create a better gasket effect during filtration. Ordinary cotton cloths are suitable for neutral filter pulp under 212℉, for acid filtration up to 68 ℉ and alkali solution under 50℉.Cotton filter cloth will swell in alkali solutions to create a better gasket effect during filtration. Ordinary cotton cloths are suitable for neutral filter pulp under 212℉, for acid filtration up to 68 ℉ and alkali solution under 50℉.