Nontherapeutic cosmetic process of depigmenting, whitening and/or bleaching keratin materials, comprises: applying a cosmetic composition comprising dithiolane compounds (I) and their salts, chelates, solvates and optical isomers in a medium. Nontherapeutic cosmetic process of depigmenting, whitening and/or bleaching keratin materials, comprises: applying a cosmetic composition comprising dithiolane compounds of formula (I) and their salts, chelates, solvates and optical isomers in a medium. Y 1> : O, NR 1> or S, preferably NH R 1> : H, a saturated linear 1-20C-, branched 3-20C- or unsaturated 2-20C hydrocarbon alkyl groups R : a saturated linear 1-20C-, branched 3-20C- or unsaturated 2-20C hydrocarbon alkyl group, saturated 1-8C alkyl having phenyl substituent (optionally substituted by one or more OH and/or 1-8C alkoxy) or phenyl (optionally substituted by one or more OH and/or by one or more 1-8C alkoxy) (all optionally substituted by OR 2>, SR 2>, NR 2>R 3>, or COOR 2>) or H R 2> : H, a saturated linear 1-5C-, branched 3-5C- or unsaturated 2-5C hydrocarbon group, or phenyl R 3> : H, a saturated linear 1-5C-, branched 3-5C- or unsaturated 2-5C hydrocarbon group, phenyl or acetyl and n : 0-2. Provided that: when Y 1> is NR 1>, R and R 1> may form a ring comprising pyrrolidine, pyrroline, piperidine, piperazine, morpholine, thiomorpholine or azepine. [Image].Linvention concerne un procédé cosmétique de dépigmentation, déclaircissement et/ou de blanchiment des matières kératiniques, notamment de la peau, comprenant lapplication dune composition cosmétique comprenant un composé dithiolane de formule (I) :dans laquelle :Y désigne O, NR1 ou SR1 désigne un atome dhydrogène un groupe alkyle en C1-C20 ou un groupe phényle éventuellement substitué R désigne un atome dhydrogène ou un groupe alkyle en C1-C20 ou un groupe phényle éventuellement substitué ou un groupe alkyle en C1-C8 possédant un substituant phényle éventuellement substitué n = 0 ou 1 ou 2 ,ainsi que leurs s
