1, cold water cleaning. When cleaning canvas bags, it is best to clean them with cold water. Hot water burns it easily. Try to wash by hand, not by machine. Canvas bags are made of cotton cloth. Do not use detergents containing bleaching ingredients.

2. Lemon juice method. When washing white bags, add some lemon juice to the water to make the clothes whiter.

3, skim milk soaking method. Soak the white silk fabric with skim milk before washing, or add 2 tablespoons of milk to the water during the last rinse, so as to keep the true color of the white silk fabric and prevent it from turning yellow.

4. Ink drop method. In a basin of clean cold water, drop 3-5 drops of pure blue ink, stir evenly by hand, put the washed white bag in water, lift it up and down for 3-5 times, and take it out to dry.