I think you you are getting what you want, but your printout statement is misleading you?

#!usr/bin/perl
use strict;

my $in = 'r;OFTaf#a2Mt9d\1'; 
         #single quote is literal quote
         #this is what your input should get
print $in, "\n";
          #print $in "as is", not within quotes

=prints
r;OFTaf#a2Mt9d\1
[download]