By Julia Banim If you’ve ever hopped into the shower with a bar ofImperial Leather, then you’ll have clocked the distinctive red and gold sticker. For those with a preference for this heritage brand, this little sticker is a marker of the sudsy quality enjoyed by customers for nearly 100 years, and a way of proudly displaying their loyalty to other bathroom users. Few will be aware however that it also has a practical purpose – and it’s absolutely genius. Now, the main thing bathers will notice about this sticker is that it’s incredibly stubborn and resilient – likely outlasting your fancy new…