A cosmetic product for the oxidative color changing of keratinic fibers, in particular human hair, comprisinga preparation (A), which is packaged in a sachet (S), whereinpreparation (A) includes (A1) water and(A2) hydrogen peroxide and(A3) at least one stabilizer from the group comprising 2,6-dipicolinic acid, 1-hydroxyethane-1,1-diphosphonic acid (HEDP), benzoic acid, salicylic acid, ethylenediamine tetra(methylenephosphonic acid) (EDTMP), diethylenetriamine penta(methylenephosphonic acid) (DTPMP), amino tris(methylenephosphonic acid) (ATMP), N,N-bis[2-[bis(carboxymethyl)-amino]ethyl]glycine, ethylenediamine-N,N′-disuccinic acid (EDDS), 2-hydroxypropylenediamine-N,N′-disuccinic acid (HPDDS), ethylenediamine-N,N′-diglutaric acid (EDDG), ethylenediamine-N,N′-bis(orthohydroxyphenyl)acetic acid (EDDHA), diphosphoric acid, hydrated tin oxide, and/or the physiologically acceptable salts thereof,the wall of sachet (S) comprises (S1) a first layer made of a first polymeric material and(S2) a second layer made of a second polymeric material and(SBa) a barrier layer, which has a penetration barrier effect for gases and water vapor.
