Drug – bio-affecting and body treating compositions – Effervescent or pressurized fluid containing – Organic pressurized fluid
Reexamination Certificate
1995-10-26
2002-11-19
Moore, Margaret G. (Department: 1712)
Drug, bio-affecting and body treating compositions
Effervescent or pressurized fluid containing
Organic pressurized fluid
C424S070160, C526S318440
Reexamination Certificate
active
06482393
ABSTRACT:
The present invention relates to novel hairsetting compositions which comprise as film-formers copolymers based on tert-butyl acrylate or tert-butyl methacrylate having a K value of from 10 to 50 and which are obtainable by free-radical polymerization of
A) from 30 to 72% by weight of tert-butyl acrylate or tert-butyl methacrylate or a mixture thereof as monomer A,
B) from 10 to 28% by weight of acrylic acid or methacrylic acid or a mixture thereof as monomer B, and
C) from 0 to 60% by weight of a free-radically copolymerizable monomer or of a free-radically copolymerizable monomer mixture as monomers C, where at least one of the monomers C produces a homopolymer having a glass transition temperature of less than 30° C.,
the carboxyl groups of the copolymers being partially or completely neutralized.
EP-A 379 082 discloses hairsetting compositions which comprise as film-formers copolymers based on tert-butyl acrylate and/or tert-butyl methacrylate having a K value of from 10 to 50, which are obtainable by free-radical polymerization of
A) from 75 to 99% by weight of tert-butyl acrylate and/or tert-butyl methacrylate,
B) from 1 to 25% by weight of acrylic acid and/or methacrylic acid, and
C) from 0 to 10% by weight of a further free-radically copolymerizable monomer,
the carboxyl groups of the copolymers being, as usual, partially or completely neutralized by amines.
Parameters of these prior-art compositions which are still in need of improvement, however, are the ease of washoff of the polymer from the hair, the solubility of the film-former in aqueous formulations, which are nowadays increasingly displacing those formulations based solely on organic solvents which are ecologically acceptable, and the handle and set of the treated hair, since hair which is treated with the prior-art hairsetting compositions generally feels too brittle or too coarse.
It is an object of the present invention to prepare a hairsetting composition which no longer has the abovementioned disadvantages.
We have found that this object is achieved by the hairsetting compositions defined at the outset.
The monomer or monomers C serve to modify the properties of the copolymer. In a preferred embodiment, monomers used are C
1
-C
18
-alkyl acrylates or methacrylates, especially C
1
-C
4
-alkyl acrylates or methacrylates, or a mixture of these (meth)acrylates with N-C
1
-C
18
-alkylacrylamides or -methacrylamides, especially N—C
1
-C
4
-alkylacrylamides or -methacrylamides. In these (meth)-acrylates and (meth)acrylamides, C
1
-C
4
-alkyl is suitably methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl or tert-butyl.
Particularly good results are obtained when C comprises un-branched C
2
-C
4
-alkyl acrylates, alone or as a mixture with branched N—C
3
-C
4
-alkylacrylamides. Particular preference is given to the use for this purpose of ethyl acrylate or of a mixture of ethyl acrylate and N-tert-butylacrylamide.
In a preferred embodiment, the composition of the copolymer used as film-former is
A) from 50 to 72% by weight, in particular from 60 to 70% by weight, of monomer A,
B) from 12 to 25% by weight, in particular from 15 to 23% by weight, of monomer B, and
C) from 3 to 38% by weight, in particular from 7 to 25% by weight, of monomer C.
The upper limit of 72% by weight for monomer A is particularly critical since above this limit the advantageous properties of the hairsetting composition of the invention are no longer found. The marked change in the spectrum of properties of the hairsetting composition between a content of 72 and 75% by weight of monomer A was surprising in particular in the context of the compositions from EP-A 379 082.
In a further preferred embodiment, the copolymer used as film-former is composed of
A) tert-butyl acrylate as monomer A,
B) methacrylic acid as monomer B, and
C) ethyl acrylate or a mixture of ethyl acrylate and N-tert-butylacrylamide as monomer C.
The copolymers described are prepared in a known manner by free-radical copolymerization of the monomers A, B and, if used, C. The reaction is carried out by the usual polymerization techniques, for example by the methods of suspension, emulsion or solution polymerization.
The polymerization reaction, which proceeds by a free-radical mechanism, is initiated by the customary peroxo or azo compounds, for example dibenzoyl peroxide, tert-butyl perpivalate, tert-butyl per-2-ethylhexanoate, di-tert-butyl peroxide, tert-butyl hydroperoxide, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, alkali metal persulfates or ammonium persulfates, azobisisobutyronitrile, hydrogen peroxide or redox initiators, advantageously in amounts of from 0.1 to 2% by weight, based on the weight of the monomers. The amounts of monomers and solvents or dispersants are advantageously chosen so as to give from 30 to 80% strength by weight solutions or dispersions, or suspensions, of the copolymers. The content of residual monomer can be reduced by postpolymerization in accordance with generally known methods.
The copolymers have K values of from 10 to 60, preferably from 15 to 40. The particular K value desired can be established in a manner known per se by appropriate choice of the polymerization conditions, such as the temperature of polymerization and the concentration of initiator. If desired, especially when employing emulsion and suspension polymerization, it may be appropriate to use regulators, especially sulfur compounds such as mercaptoethanol, 2-ethylhexyl thioglycolate, thioglycolic acid or dodecylmercaptan, in order to reduce the K value. The K values are measured in accordance with Fikentscher, Cellulosechemie, Vol. 13 (1932) 58 to 64 at 25° C. in 1% strength by weight ethanolic solution and are a measure of the molecular weight.
Such copolymers normally have glass transition temperatures of between 50 and 130° C., in particular between 60 and 100° C.
When the hairsetting composition is prepared by emulsion polymerization the resulting dispersion can be either incorporated directly into an aqueous hairsetting formulation or dried, for example by spraydrying, so that the hairsetting composition can be processed and used in powder form.
For use in the hairsetting compositions of the invention, the carboxyl groups of the copolymers thus obtained are usually neutralized with an alkali metal hydroxide or, preferably, with an amine, partially or completely, advantageously to the extent of from 5 to 100%, preferably from 30 to 95%. Neutralization is preferably carried out with
a mono-, di- or trialkanolamine having 2 to 5 carbon atoms in the alkanol radical, which may be in etherified form, for example mono-, di- and triethanolamine, mono-, di- and tri-n-propanolamine, mono-, di- and triisopropanolamine, 2-amino-2-methylpropanol and di(2-methoxyethyl)amine,
an alkanediolamine having 2 to 5 carbon atoms, for example 2-amino-2-methyl-1,3-propanediol and 2-amino-2-ethyl-1,3-propanediol, or
a primary, secondary or tertiary alkylamine having a total of 5 to 10 carbon atoms, for example N,N-diethylpropylamine.
Particularly good results are obtained with 2-amino-2-methylpropanol, triisopropanolamine and 2-amino-2-ethyl-1,3-propanediol.
Particularly suitable alkali metal hydroxides for the neutralization are sodium hydroxide and potassium hydroxide.
The hairsetting compositions according to the invention are employed, for example, as gels, lotions, mousses and, in particular, as hairsprays. Particularly preferred hairspray formulations are those comprising the following constituents:
from 0.1 to 20% by weight, preferably from 0.5 to 10% by weight, in particular from 2 to 10% by weight, of the partially or completely neutralized copolymer
from 1 to 99.9% by weight, preferably from 5 to 50% by weight, in particular from 10 to 40% by weight, of water
from 0 to 95% by weight, preferably from 20 to 60% by weight, in particular from 25 to 50% by weight, of a customary organic solvent such as, in particular, ethanol, isopropanol or dimethoxymethane, or else acetone, n-propanol, n-butanol, 2-methoxy-1-propanol, n-pentane, n-hexane, cyclohexane, n-heptane, n-oc
Blankenburg Rainer
Sanner Axel
Schehlmann Volker
Sperling-Vietmeier Karin
BASF - Aktiengesellschaft
Keil & Weinkauf
Moore Margaret G.
LandOfFree
Hairsetting compositions does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Hairsetting compositions, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hairsetting compositions will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2984814