Abstract: This invention relates to improved hair waving and straightening compositions of matter. The novel compositions of matter of this invention comprise a sulfite and/or bisulfite reducing system, urea, a cationic polyquaternary resin of such a nature that in combination with the urea in the reducing system a hair waving and/or straightening effect equivalent to conventional thioglycolate systems is effectuated without the attendant unpleasant odors associated with the thioglycolate systems. In addition, the reducing system of this invention is less damaging to the hair and skin than the thioglycolate systems. The system of course may be used either with or without heat such as heat from hair dryers. In order to achieve the above-mentioned objective, the compositions of this invention are at a pH in the range of above 5.5 to about 8.5, preferably 6.5. Such hair waving and straightening compositions may contain any conventional additives employed in the known sulfite and/or bisulfite (e.g.

Abstract: Keratinous material, such as human hair, in which disulfide linkages have been ruptured to form disulfide linkages can be set using diimidates, and disuccinimidyl compounds as disclosed herein.