The process for whitening doilies that have yellowed might need to be repeated several times, depending on how soiled the lace is. The material has to be treated by hand, since the agitation inside of a washing machine is too strong for the material, even if the machine is set on the delicate cycle. The drying process will also help bleach the doilies since you'll air dry them in the sun. For best results, wash the doilies in the late morning (like 11 a.m.), so by the time you're ready to lay them out to dry, the sun will be at its hottest.
Place the doilies in the lingerie bag and zip it closed.
Fill your sink 1 inch from the top with cold water.
Put on the rubber gloves to protect your hands from the undiluted hydrogen peroxide.
Pour 2 cups of 3-percent hydrogen peroxide into the measuring cup.
Add the hydrogen peroxide into the sink.
Put your gloved hands into the water and lightly agitate it for 60 seconds to thoroughly disperse the hydrogen peroxide.
Gently sit the lingerie bag into the water.
Hold the top of the bag and slowly pull it back and forth in the sink for 60 seconds to lightly agitate the water.
Lay the bag flat on the bottom of the sink and let it sit for 15 minutes.
Repeat Steps 8 and 9 every 15 minutes for the next 45 minutes. (After one hour, you will have agitated the doilies in the bag four times in 15-minute intervals.)
Remove the lingerie bag from the sink and drain the water.
Refill the sink with cold water.
Put the lingerie bag back into the water and gently pull it back and forth for 60 seconds to rinse off the hydrogen peroxide solution.
Lift the bag from the sink and let the excess water drain out.
Drain the sink and then lay the lingerie bag back on the bottom.
Place a small table beneath a window sill.
Spread a white towel over the top of the table.
Remove the doilies one at a time from the lingerie bag
Hold each doily up in the sink to let the excess water drain from it.
Lay each doily flat on the white towel.
Spread the other white towel flat over the top of the doilies.
Gently press on the towel to blot remaining water from the doilies.
Remove the top towel and let the doilies lie in the sunlight until they dry.
If all of the yellow isn't removed, wait several days before repeating the whitening process. Consult with a professional lace restoration company about handling your linens if you can't get the doilies cleaned to your satisfaction.
Don't use a stronger solution than 3-percent hydrogen peroxide to wash the doilies. It will be too harsh on the lace.