Flexible solid cosmetic composition comprising anionic surfactants and solid particles, and cosmetic treatment process

1. An aqueous cosmetic hair composition in flexible solid form, comprising:

at least one anionic surfactant wherein at least one anionic surfactant is chosen from acyl isethionates represented by the following formula:

R—C(O)—O—CH 2 CH 2 SO 3 M

wherein:

R—C(O) is an acyl group comprising from 6 to 16 carbon atoms, and

M denotes a cosmetically acceptable counterion,

at least one type of solid full particles chosen from silicas, clays, pigments, pearlescent agents, or mixtures thereof, wherein the total amount of solid particles ranges from 6.7% to 15% by weight, relative to the total weight of the composition, and

water in an amount of 35% to 80% by weight;

wherein the total amount of anionic surfactant ranges from 25% to 70% by weight, relative to the total weight of the composition;

wherein the total amount of acyl isethionates ranges from 12% to 35% by weight, relative to the total weight of the composition, and

wherein the composition has a threshold stress at 25° C. of greater than or equal to about 100 Pa.

2. The composition according to claim 1 , wherein the composition has a penetration force at 25° C. of greater than or equal to about 210 g.

3. The composition according to claim 1 , wherein the composition has a viscoelastic spectrum at 25° C., measured between 10 −2 Hz and 100 Hz, such that there is no crossover point between the curves G′ and G″, G′ always being strictly greater than G″.

4. The composition according to claim 1 , wherein

M denotes a cosmetically acceptable counterion chosen from cocoyl isethionates, lauroyl isethionates, or mixtures thereof.

5. The composition according to claim 1 , further comprising at least one additional anionic surfactant chosen from:

C 6 -C 24 alkyl sulfates or C 12 -C 20 alkyl sulfates;

C 6 -C 24 alkyl ether sulfates, C 12 -C 20 alkyl ether sulfates, C 6 -C 24 alkyl ether sulfates comprising from 2 to 20 ethylene oxide units, or C 12 -C 20 alkyl ether sulfates comprising from 2 to 20 ethylene oxide units;

C 6 -C 24 acyl glutamates, C 12 -C 20 acyl glutamates, or glutamates;

C 6 -C 24 acylsarcosinates, C 12 -C 20 acylsarcosinates, or palmitoylsarcosinates;

C 6 -C 24 acyl lactylates, C 12 -C 20 acyl lactylates, or behenoyl lactylates;

(C 6 -C 24 )alkyl ether carboxylates, or (C 12 -C 20 )alkyl ether carboxylates; or

C 6 -C 24 alkylsulfosuccinates, C 12 -C 20 alkylsulfosuccinates, or laurylsulfosuccinates.

6. The composition according to claim 1 , wherein the total amount of anionic surfactant ranges from 25% to 65% by weight, relative to the total weight of the composition.

7. The composition according to claim 1 , wherein the at least one type of solid full particles is chosen from:

kaolin; or

organic or inorganic colored pigments, or uncolored pearlescent agents.

8. The composition according to claim 1 , further comprising at least one conditioning agent chosen from cationic surfactants, fatty esters other than triglycerides, fatty alcohols, vegetable oils, C 6 -C 16 liquid hydrocarbons, hydrocarbons having more than 16 carbon atoms, ceramides, vegetable or animal waxes; non-silicone cationic polymers, non-silicone amphoteric polymers, or silicones.

9. The composition according to claim 8 , wherein the total amount of conditioning agent ranges from 0.001% to 20% by weight, relative to the total weight of the composition.

10. The composition according to claim 1 , further comprising at least one polyol represented by the following formula:

wherein:

R′ 1 , R′ 2 , R′ 3 and R′ 4 are chosen, independently of each other, a hydrogen atom, a C 1 -C 6 alkyl radical or a C 1 -C 6 mono- or polyhydroxyalkyl radical,

A represents a linear or branched alkylene radical comprising from 1 to 18 carbon atoms, and optionally from 1 to 9 oxygen atoms, wherein A does not include a hydroxyl group,

m denotes 0 or 1.

11. The composition according to claim 10 , wherein the total amount of polyol ranges from 0.1% to 60% by weight, relative to the total weight of the composition.

12. The composition according to claim 1 , further comprising at least one non-particulate antidandruff agent chosen from:

1-hydroxy-2-pyrolidone derivatives;

2,2′-dithiobis(pyridine N-oxide);

trihalocarbamides;

triclosan;

azole compounds;

antifungal polymers;

extracts of at least one non-photosynthetic, non-fruiting filamentous bacteria;

ellagic acid, ethers of ellagic acid, salts of ellagic acid, salts of ethers of ellagic acid, or ellagic acid tannins;

allantoin, coal or wood tars and derivatives thereof, undecylenic acid, fumaric acid, allylamines, or terbinafine.

13. The composition according to claim 12 , wherein the total amount of non-particulate antidandruff agent ranges from 0.01% to 10% by weight, relative to the total weight of the composition.

14. The composition according to claim 1 , comprising water in an amount ranging from 40% to 80% by weight, relative to the total weight of the composition.

15. A cosmetic hair treatment method for caring for, cleaning, and/or conditioning keratin materials, the method comprising:

applying to the keratin materials a composition comprising:

at least one anionic surfactant wherein at least one anionic

surfactant is chosen from acyl isethionates represented by the

following formula:

R—C(O)—O—CH 2 CH 2 SO 3 M

wherein:

R—C(O) is an acyl group comprising from 6 to 16 carbon atoms, and

M denotes a cosmetically acceptable counterion,

at least one type of solid full particles chosen from silicas, clays, pigments, pearlescent agents, or mixtures thereof, wherein the total amount of solid particles ranges from 6.7% to 15% by weight, relative to the total weight of the composition, and

water in an amount of 35% to 80% by weight;

wherein the total amount of anionic surfactant ranges from 25% to 70% by weight, relative to the total weight of the composition; and

optionally rinsing after an optional leave-on time;

wherein the total amount of acyl isethionates ranges from 12% to 35% by weight, relative to the total weight of the composition, and

wherein the composition has a threshold stress at 25° C. of greater than or equal to about 100 Pa.