13  US 6,500,796 Bl  14  Formula III  Polysciences, with a MW 2000, and 80% hydroxyethylated  poly(ethyleneimine) from Aldrich.  A  typical amount of amino-functional polymer to be  employed in the composition of the invention is preferably  up to  90% by weight, preferably from 0.01 % to 50% active  Formula IV depicts an amino-functional polymer com› prising a PEI backbone wherein the backbone nitrogens are  modified by substitution (i.e. by -(CH$_{2}$ CH$_{2}$ OhH or  methyl), quaternized, oxidized to N-oxides or combinations  thereof. The resulting polymer has the formula  Formula IV  by weight, more preferably from 0.1 % to 20% by weight and  most preferably from  0.5% to 15% by weight of the com- position.  Crystal Growth Inhibitor  A  crystal growth inhibitor  (CGI)  is  an essential compo› nent of the invention. By "crystal growth inhibitor", it is  meant a compound that reduces the rate of formation of  inorganic microcrystals, thereby reducing the size and/or the  amount of such micro-crystals at the fabric surface.  The suitable CGI for use herein can be defined by the  following test procedure, so called crystal growth inhibition  test measurement.  Crystal Growth Inhibition Test Measurement  The ability for a compound to inhibit crystal growth can  be assessed by evaluating the impact in vitro on the growth  rate of inorganic micro-crystals. For this purpose, a system  In the above examples, not all nitrogens of a unit class  comprise the same modification. The present invention  allows the formulator to have a portion of the secondary  amine nitrogens ethoxylated while having other secondary  amine nitrogens oxidized to N-oxides. This also applies to  the primary amine nitrogens, in that the formulator may  choose to modify all or a portion of the primary amine  nitrogens with one or more substituents prior to oxidation or  quaternization. Any possible combination of  R’  groups can  be substituted on the primary and secondary amine  nitrogens, except for the restrictions described herein above.  Commercially available amino-functional polymer suit- able for use herein are poly(ethyleneimine) with a  MW  1200, hydroxyethylated poly(ethyleneimine) from 