The actual formula for RL paint was pretty much secret and even if someone could somehow match the formula no one could guarantee that the new paint would match the old paint EXACTLY. No two batches of paint are exactly the same which is why painters always mix the cans, even if they are the same batch numbers. Secondly, your paint has aged. It’s no longer exactly the same shade as it was when new.
Rather than have the touch ups stand out like a sore thumb you would be better off finding another paint that comes close to what you have and repaint the entire room.
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