Patterns on a white background - keeping the white bit white and not grey

[InTheDollshouse]

Some of DD's tops and PJs are coloured patterns on a white background, and after a while the background has gone rather grey the way that whites sometimes do. Is there anything I can do about this? Most of the things you would normally do to make whites white would presumably ruin the coloured pattern?

Watching this one with great interest as i am slightly obsessed with whites staying white....

Note to self, must get out more!

I wash in with the other white, with a glo white sachet and a colour catcher - not sure what it does for the coloured bit in the long term tho

You can wash or soak them with "Colour Run" from time to time, to get the loose dye back out. I don't think it does anything to the actual coloured parts.

I use colour catchers.

My DS has loads of t shirts that are coloured short sleeve with long white sleeve 'underneath'.

Tis amazing the colour that the come out.

OK, didn't read properly.

Do not know how to rectify safely, for prevention see previous post!