It's probably the detergent that's causing the trouble. SOAP, washing powder, such as alkaline detergent, because everyone into the washing machine, no water dissolved first, there will be a partial discoloration of the uneven situation.
High temperature can be bactericidal, but will make the bed products fade, sterilization there are many ways, do not choose this kind of suicide washing, high-temperature sterilization only for the hotel white sheets.
Soak the washing time not exceeding 30 minutes or fade easily.
Because the pigment in the sunlight and the heat of the action, was oxidized metamorphism, resulting in permanent fading. Therefore, in the sun, should not be at midday exposure, not when the sun time exposure too long, it is best to choose the negative sun.