Bleaching and dyeing; fluid treatment and chemical modification – Dyeing involving animal-derived natural fiber material ,... – Hair dyeing
Patent
1989-09-21
1991-10-01
Clingman, A. Lionel
Bleaching and dyeing; fluid treatment and chemical modification
Dyeing involving animal-derived natural fiber material ,...
Hair dyeing
8405, 8429, 8431, 8557, 8594, 8599, A61K 713, B01J 1302, D06P 308
Patent
active
050530518
DESCRIPTION:
BRIEF SUMMARY
The invention relates to a mixture for the oxidative dyeing of human or animal hair, which is prepared immediately before application by mixing an oxidant and a dye base in cream, gel or powder form containing at least one oxidation dye, and is adjusted to a pH value in the range from 8.0 to 10.5, and to a method for the redyeing of dyed hair, in which a hair dye which in the ready-to-use state has a pH value in the range between 8.0 to 10.5 is prepared from an oxidant and a dye base in powder, cream or gel form containing at least one oxidation dye, which then is applied to the regrowth of the hair that is to be redyed and made to act thereon for a given period of time, and then is combed into the already-dyed hair lengths and ends where it is made to act for an additional given period of time, and lastly is washed out.
For the enduring coloration of human hair, alkaline dye bases containing at least one oxidative dye are used in cream, gel or powder form, which are mixed immediately before application with an acid oxidant, e.g., hydrogen peroxide or an emulsion containing hydrogen peroxide, to form the ready-to-use hair dye for application to the hair. The coloring is produced in this case by the reaction of specific developer substances with specific coupler substances in the presence of a suitable oxidant. The ready-to-use preparation is decidedly in the alkaline range, so that the surfaces of the hairs to be dyed are opened up in a manner advantageous for the penetration of the oxidation dyes. On the other hand, alkaline preparations also affect the hair so that, especially in the case of repeated actions, e.g., repeated redyeing, they can cause harm to the hair. Such redyeing, however, is necessary in order to match the color of the undyed hair regrowth to the already-dyed hair lengths, in which case, as a rule, the previously dyed hair lengths must also be color-refreshed if they have faded from the original color in the course of time due to external factors such as solar radiation, frequent washing, and the like.
The invention is addressed to the problem of finding a hair dye as well as a method for the preparation and subsequent application of the dye to the hair that is to be treated, which will not lead to the above-described hair damage, even after repeated redyeing.
The hair dye prepared from an oxidant and a dye base in cream, gel or powder form containing at least one oxidative dye, in accordance with the invention is characterized by the fact that, in the freshly prepared state, it contains a microencapsulated, acid-reacting compound in an amount which shifts the pH of the hair dye into the neutral, weakly alkaline (pH.ltoreq.8) or weakly acid range, and that the encapsulating material for the acid-reacting compound is soluble in the alkaline dye or at least is variable in its strength properties in the sense of weakening them, the wall thickness of the microcapsules being so adjusted that within a period of time between 10 and 60 minutes they are dissolved or weakened to the extent that the acid-reacting compound can emerge into the dye by itself or upon the exercise of an additional mechanical stress.
The acid-reacting compound is, for example, an acrylic resin containing carboxyl groups (Rohagit S) or it is an acid such as citric acid, tartaric acid or malic acid, which when mixed with the alkaline dye produces a color change in addition to the pH shift or contains an indicator which causes such a color change.
Also advantageous is the use or concomitant use of ascorbic acid as the acid-reacting compound, because, in addition to the shifting of the pH of the dye towards neutrality or acidity--which is delayed with respect to the above-mentioned acid-reacting compounds--also has a reducing action on the hydrogen peroxide contained as oxidant in the prepared hair dye. In the reducing reaction (redox effect) exothermic heat is produced, which results in an acceleration of the dyeing process. The addition of the encapsulated ascorbic acid thus produces a delayed shift of the pH value, a red
REFERENCES:
patent: 3975515 (1976-08-01), Wajaroff et al.
patent: 4020850 (1986-11-01), Bachmann et al.
patent: 4425132 (1984-01-01), Grollier et al.
patent: 4844711 (1989-07-01), Hoppe et al.
Lorenz Herbert
Segawa Hirotsugu
Tennigkeit Jurgen
Clingman A. Lionel
Goldwell GmbH
LandOfFree
Means and method for the oxidative dyeing, especially the redyei does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Means and method for the oxidative dyeing, especially the redyei, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Means and method for the oxidative dyeing, especially the redyei will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1752382