Process for semipermanent straightening of curly, frizzy or wavy hair

Abstract

A treatment of human hair by means of solutions of Glyoxylic acid that, when used in combination with mechanical straightening by means of hair-straightening irons set at a temperature of approximately 200 C.+/30 C., allow for the semi-permanent changing of the shape of hair from curly and/or frizzy to straight for at least six consecutive washings with water and shampoo.

Claims

1. A process for semi-permanent straightening of human hair, comprising the following steps: a) application of aqueous solution of Glyoxylic acid on hair; b) permanence of said solution in contact with hair for a time for approximately 60 minutes; c) drying of hair with hair-dryer; d) hair straightening with hair-straightening iron, set at a temperature of approximately 200 C.; and wherein the process is conducted to maintain a pH less than 7, and wherein the Glyoxylic acid is dissolved in water in concentration between 4.5 and 10 percent by weight, wherein the process is conducted without substances able to react with cysteine disulphide bridges.

2. The process of claim 1, wherein the hair is covered with a plastic cap during step b).

3. The process of claim 1, wherein step a) further comprises application of a mixture of Diacetyl and Acetoin on hair.

4. The process of claim 3, wherein said mixture of Diacetyl and Acetoin is dissolved in said aqueous solution of Glyoxylic acid in concentration comprised between 1 and 5% by weight.

Description

EXAMPLE 1

(1) TABLE-US-00001 Water 95.5 grams Glyoxylic Acid 4.5 grams (0.6 Molar)

EXAMPLE 2

(2) TABLE-US-00002 Water 90 grams Glyoxylic Acid 10 grams (1.35 Molar)

EXAMPLE 3

(3) TABLE-US-00003 Water 85.5 grams Glyoxylic Acid 14.5 grams (1.9 Molar)

(4) These solutions were placed in contact with hair that had been previously washed with shampoo according to common use.

(5) Said solutions were then applied on hair with a rigid bristle brush.

(6) Hair was covered with a plastic cap to reduce water evaporation, left in contact with said solutions for 30, 60, 120 minutes, and then dried with hair dryer according to common use. In some embodiments, hair is left in contact with said solution for approximately 60 minutes.

(7) Once dry, hair was straightened with hair-straightening iron heated at average temperature of approximately 210 C.

(8) Finally, hair was washed with shampoo and dried.

(9) At the end of treatment, hair was shiny, straight, soft to touch, with a particularly pleasant general aspect.

(10) Experimental tests were carried out on hair straightening effect that evaluate the reduction of curves and volume in hair.

(11) In particular, comparative tests were carried out, comparing the straigthening effect after mechanical action/heat of irons obtained by putting hair in contact with: water only compositions according to the present invention; a known composition, such as the composition described in example 3 of WO 2007/135299.

(12) To that purpose, the solution described in example 3 of WO 2007/135299 was prepared, consisting in a solution of pyruvic acid 4 Molar (35.2% by weight) in water. Said solution was used according to the instructions contained in WO 2007/135299, that is hair temperature of 40 C., 25 minute contact time and iron temperature of 180.

(13) The results of the tests are shown in the enclosed tables 1 to 5.

(14) Said tests were carried out with different contact time of the solution with hair. Tables 1 to 4 show the results obtained with the composition of the invention for 60 minute contact time. Instead, table 5 shows the results obtained with the composition of the invention for 30 and 120 minute contact time.

(15) Additional tests were carried out to see whether the effect obtained with solutions of glyoxylic acid could be replicable also when the solution of glyoxylic acid was added to a commercial cosmetic formulation (i.e. substances that are normally used in the cosmetic sector).

(16) To that end an additional test was carried out on a composition of the invention by adding a solution of Glyoxylic acid with a cosmetic found on the market for hair treatment. In particular, a hair straightening test was carried out using a cosmetic product found on the market (Crema Balsamo BALM produced by Tricobiotos spa Vaiano (PO)Italy), without semipermanent hair straightening effect.

(17) 80 grams of said cosmetic product were added to 20 grams of aqueous solution of Glyoxylic acid at 50% by weight.

(18) After carrying out the same hair treatment operations described in the previous pages, results similar to the ones obtained in the tests that were carried out using the same solution of example 2 of the invention were obtained.

(19) As shown in the tables, all tested compositions have a higher straightening effect compared to the simple use of water and hair straightening iron. In particular, the method described in WO 2007/135299 has proved to achieve satisfactory results only for the first four washings, and afterwards hair resumed its original shape (curly and frizzy).

(20) Instead, with the method of the invention, a remarkable result was obtained at the end of the hair treatment: hair was shiny, straight, soft to touch, with a generally pleasant aspect that was maintained also after six consecutive washings with water and shampoo.

(21) The efficacy of the treatment of the invention, in the modification of the shape of hair, has proved to be stable aver time for at least six washings, rinsings and dryings in common use conditions of hair shampoo.

(22) As shown in tables 1-5, the method of the invention has given the best results with the solution of glyoxylic acid described in example 2 for 60 minute contact time on hair.

(23) Better results were even achieved by adding the aqueous solution of glyoxylic acid to a mixture of Diacetyl and Acetoin, in ponderal ratio between 1 and 5% with respect to the total aqueous solution.

(24) The ponderal ratio between Diacetyl and Acetoin can change according to the purity of substances. For illustrative purposes, 1:10, 1:1 and 10:1 diacetyl/acetoin ponderal ratios were considered in examples 4, 5 and 6. Following are composition examples of some of the mixtures used for the tests.

EXAMPLE 4

(25) TABLE-US-00004 Water 86 grams Glyoxylic acid 10 grams Diacetyl/Acetoin mixture in 1:10 ratio 4 grams

EXAMPLE 5

(26) TABLE-US-00005 Water 86 grams Glyoxylic acid 10 grams Diacetyl/Acetoin mixture in 1:1 ratio 4 grams

EXAMPLE 6

(27) TABLE-US-00006 Water 86 grams Glyoxylic acid 10 grams Diacetyl/Acetoin mixture in 10:1 ratio 4 grams

(28) Also in this case, a comparison was made with the method described in example 3 of WO 2007/135299.

(29) Additional tests were carried out to see whether the effect obtained with the aforementioned mixtures could be replicable also in the case when the mixtures were added to a cosmetic formulation.

(30) So, an additional test was carried out by adding a cosmetic hair treatment found on the market to glyoxylic acid and Acetoin and Diacetyl mixture. In particular, a hair straightening test was carried out using a cosmetic product found on the market (Easy care relaxing conditioner produced by Unicompany spa Rome-Italy), without semipermanent hair straightening effect.

(31) 76 grams of said cosmetic were added to 20 grams of aqueous solution of Glyoxilyc acid at 50% by weight and 4 grams of Diacetyl/Acetoin mixture in 1/1 weight/weight ponderal ratio.

(32) After carrying out the same hair treatment operations described in the previous pages, the same results obtained in the tests that were carried out using the same solution as example 2 of the invention (Water+Glyoxylic AcidDiacetyl/Acetoin mixutre in 1/1 ratio (weight/weight)) were obtained.

(33) As shown in tables 5 to 10, at the end of the treatment with addition of Diacetyl and Acetoin mixture, a remarkable result was obtained, which was even better than a solution exclusively containing glyoxylic acid.

Definitions

(34) Glyoxilyc Acid: (CAS number: 563-96-2 or, in aqueous solution, CAS number: 298-12-4). Its use in the cosmetic sector as buffering substance is considered to be safe and is permitted without restrictions.

(35) Diacetyl: (CAS number 431-03-8). It is an organic substance produced by lactic bacteria in presence of carbohydrates and oxygen (see EP0430406). In the production of Diacetyl by means of bacterial fermentation also Acetoin is produced by the same bacteria. Diacetyl is normally used as aroma in the food industry.

(36) Acetoin: (CAS number 513-86-0). It is an organic substance produced by lactic bacteria in presence of carbohydrates and oxygen (see EP0430406). In the production by means of bacterial fermentation of Acetoin, Diacetyl is produced by the same bacteria. Acetoin is normally used as aroma in the food industry.

(37) Mixture: solution composed of Diacetyl and Acetoin in variable ponderal ratio.

(38) Buffering agent: when dissolved in water, it reduces the pH variation of the solution to the addition of acid or alkalinesubstances.

(39) Semipermanent treatment: treatment in acid environment (pH lower than 7) of curly or frizzy hair to straighten it, with permanence in such a condition for at least six washings with water and shampoo, without using substances able to react with cystine disulphide bridges or by means of alkali

(40) Permanent treatment: hair treatment to bring it to curly or straight condition with permanence in such a condition for at least six washings by means of oxido-reduction process of disulphide bridges of the cystine contained in hair or by means of hydrolysis of peptidic bonds with alkali (pH higher than 7). The technique is well known and described in WO 2007/135299 A1 and U.S. Pat. No. 4,409,204.

(41) Hair-straightening iron: Electrical heating device that is used by associating heat and pressure to straighten hair. It is generally composed of two flat heating elements, covered with various materials, between which a lock of hair is pressed at a time. Said hair-straightening irons are commonly found on the market.

(42) Hair dryer: ordinary hair-drying device with heating resistance and fan.

(43) TABLE-US-00007 TABLE 1 AFRO TYPE, NATURAL CURLY HAIR STRAIGHTENING EFFECT ASSESSMENT (curve reduction) Temp. Hair of hair fiber straight- after no. 1 after 2nd after 3rd after 4th after 5th after 6th temper- Contact ening shampoo shampoo shampoo shampoo shampoo shampoo ature time iron and and and and and and TEST PREPARATION ( C.) (minutes) ( C.) drying drying drying drying drying drying WATER 100 ml 30 60 210 () () () () () () 95.5 g WATER + 4.5 g GLYOXYLIC ACID 30 60 210 (+++) (+++) (++) (++) (+) (+) 90 g WATER + 10 g GLYOXYLIC ACID 30 60 210 (+++) (+++) (+++) (++) (++) (++) 85.5 g WATER + 14.5 g GLYOXYLIC ACID 30 60 210 (+++) (+++) (+++) (++) (++) (++) 76 g CREMA BALSAMO Tricobiotos + 20 g 30 60 210 (+++) (+++) (+++) (++) (++) (++) solution of GLYOXYLIC ACID 50% in water (w/w) PYRUVIC ACID 4 Molar 40 25 180 (+++) (+++) (++) (++) (+) (+/) (Example 3 of WO2007/135299 A1) Reduction Reduction Reduction Reduction No lower between between between Reduc- MEASURED PARAMETER effect than 25% 26 and 50% 51 and 75% 76 and 90% tion >90% % Reduction of number of curves found in 30 cm of hair +/ + ++ +++ ++++ (no. of residual curves/no. of initial curves 100)

(44) TABLE-US-00008 TABLE 2 AFRO TYPE, NATURAL CURLY HAIR VOLUME REDUCTION ASSESSMENT (reduction of hair spatial volume) Temp. Hair of hair fiber straight- after no. 1 after 2nd after 3rd after 4th after 5th after 6th temper- Contact ening shampoo shampoo shampoo shampoo shampoo shampoo ature time iron and and and and and and TEST PREPARATION ( C.) (minutes) ( C.) drying drying drying drying drying drying WATER 100 ml 30 60 210 () () () () () () 95.5 g WATER + 4.5 g GLYOXYLIC ACID 30 60 210 (+++) (+++) (++) (++) (+) (+) 90 g WATER + 10 g GLYOXYLIC ACID 30 60 210 (+++) (+++) (+++) (++) (++) (+) 85.5 g WATER + 14.5 g GLYOXYLIC ACID 30 60 210 (+++) (+++) (++) (++) (++) (+) 76 g CREMA BALSAMO Tricobiotos + 20 g 30 60 210 (+++) (+++) (+++) (++) (++) (+) solution of GLYOXYLIC ACID 50% in water (w/w) PYRUVIC ACID 4 Molar 40 25 180 (+++) (+++) (++) (++) (+) (+/) (Example 3 of WO2007/135299 A1) Reduction Reduction Reduction Reduction No lower between between between MEASURED PARAMETER effect than 25% 26 and 50% 51 and 75% 76 and 90% Riduzione >90 % Reduction of hair volume (circumference of lock with 1.0 g +/ + ++ +++ ++++ weight measured at half length) (test final diameter/initial diameter 100)

(45) TABLE-US-00009 TABLE 3 European TYPE, NATURAL CURLY HAIR STRAIGHTENING EFFECT ASSESSMENT (curve reduction) Temp. Hair of hair fiber straight- after no. 1 after 2nd after 3rd after 4th after 5th after 6th temper- Contact ening shampoo shampoo shampoo shampoo shampoo shampoo ature time iron and and and and and and TEST PREPARATION ( C.) (minutes) ( C.) drying drying drying drying drying drying WATER 100 ml 30 60 210 () () () () () () 95.5 g WATER + 4.5 g GLYOXYLIC ACID 30 60 210 (++++) (+++) (+++) (++) (++) (+) 90 g WATER + 10 g GLYOXYLIC ACID 30 60 210 (++++) (++++) (+++) (+++) (++) (++) 85.5 g WATER + 14.5 g GLYOXYLIC ACID 30 60 210 (++++) (+++) (+++) (++) (++) (+) 76 g CREMA BALSAMO Tricobiotos + 20 g 30 60 210 (++++) (++++) (+++) (+++) (++) (++) solution of GLYOXYLIC ACID 50% in water (w/w) PYRUVIC ACID 4 Molar 40 25 180 (+++) (+++) (++) (++) (+) (+/) (Example 3 of WO2007/135299 A1) Reduction Reduction Reduction Reduction No lower between between between MEASURED PARAMETER effect than 25% 26 and 50% 51 and 75% 76 and 90% Riduzione >90 % Reduction of number of curves found in 30 cm of hair +/ + ++ +++ ++++ (no. of residual curves/no. of initial curves 100)

(46) TABLE-US-00010 TABLE 4 European TYPE, NATURAL CURLY HAIR VOLUME REDUCTION ASSESSMENT (reduction of hair spatial volume) Temp. Hair of hair fiber straight- after no. 1 after 2nd after 3rd after 4th after 5th after 6th temper- Contact ening shampoo shampoo shampoo shampoo shampoo shampoo ature time iron and and and and and and TEST PREPARATION ( C.) (minutes) ( C.) drying drying drying drying drying drying WATER 100 ml 30 60 210 () () () () () () 95.5 g WATER + 4.5 g GLYOXYLIC ACID 30 60 210 (++++) (+++) (+++) (+++) (+++) (++) 90 g WATER + 10 g GLYOXYLIC ACID 30 60 210 (++++) (++++) (+++) (+++) (++) (++) 85.5 g WATER + 14.5 g GLYOXYLIC ACID 30 60 210 (++++) (+++) (++) (++) (++) (+) 76 g CREMA BALSAMO Tricobiotos + 20 g 30 60 210 (++++) (++++) (+++) (+++) (++) (++) solution of GLYOXYLIC ACID 50% in water (w/w) PYRUVIC ACID 4 Molar 40 25 180 (++++) (+++) (++) (++) (+) (+/) (Example 3 of WO2007/135299 A1) Reduction Reduction Reduction Reduction No lower between between between MEASURED PARAMETER effect than 25% 26 and 50% 51 and 75% 76 and 90% Riduzione >90 % Reduction of hair volume (circumference of lock +/ + ++ +++ ++++ with 1.0 g weight measured at half length) (test final diameter/initial diameter 100)

(47) TABLE-US-00011 TABLE 5 AFRO TYPE, NATURAL CURLY HAIR EVALUATION OF STRAIGHTENING EFFECT (reduction of curves) with different contact time Temp. Hair of hair fiber straight- after no. 1 after 2nd after 3rd after 4th after 5th after 6th temper- Contact ening shampoo shampoo shampoo shampoo shampoo shampoo ature time iron and and and and and and TEST PREPARATION ( C.) (minutes) ( C.) drying drying drying drying drying drying WATER 100 ml 30 30 210 () () () () () () WATER 100 ml 30 120 210 () () () () () () 95.5 g WATER + 4.5 g GLYOXYLIC ACID 30 30 210 (++) (++) (++) (++) (+) (+/) 90 g WATER + 10 g GLYOXYLIC ACID 30 30 210 (+++) (++) (++) (++) (+) (+) 85.5 g WATER + 14.5 g GLYOXYLIC ACID 30 30 210 (+++) (++) (++) (++) (+) (+/) 76 g CREMA BALSAMO Tricobiotos + 20 g 30 30 210 (+++) (+++) (+++) (++) (++) (+) solution of GLYOXYLIC ACID 50% in water (w/w) 95.5 g WATER + 4.5 g GLYOXYLIC ACID 30 120 210 (++++) (+++) (+++) (++) (++) (+) 90 g WATER + 10 g GLYOXYLIC ACID 30 120 210 (++++) (++++) (++++) (+++) (++) (++) 85.5 g WATER + 14.5 g GLYOXYLIC ACID 30 120 210 (++++) (++++) (+++) (++) (++) (+) 76 g CREMA BALSAMO Tricobiotos + 20 g 30 120 210 (++++) (++++) (+++) (+++) (++) (++) solution of GLYOXYLIC ACID 50% in water (w/w) PYRUVIC ACID 4 Molar 40 25 180 (++++) (++++) (+++) (+++) (++) (+) (Example 3 of WO2007/135299 A1) Reduction Reduction Reduction Reduction No lower between between between MEASURED PARAMETER effect than 25% 26 and 50% 51 and 75% 76 and 90% Riduzione >90 % Reduction of number of curves found in 30 cm of hair +/ + ++ +++ ++++ (no. of residual curves/no. of initial curves 100)

(48) TABLE-US-00012 TABLE 6 AFRO TYPE, NATURAL CURLY HAIR STRAIGHTENING EFFECT ASSESSMENT (curve reduction) Temp. Hair of hair fiber straight- after no. 1 after 2nd after 3rd after 4th after 5th after 6th tempe- Contact ening shampoo shampoo shampoo shampoo shampoo shampoo rature time iron and and and and and and TEST PREPARATION ( C.) (minutes) ( C.) drying drying drying drying drying drying WATER 100 ml 30 60 210 () () () () () () 76 g WATER + 20 g solution of GLYOXILYC 30 60 210 (++++) (++++) (++++) (+++) (+++) (++) ACID 50% in water w/w + 4 g DIACETYL/ ACETOIN mixture 1/10 w/w 76 g WATER + 20 g solution of GLYOXILYC 30 60 210 (++++) (++++) (++++) (+++) (+++) (+++) ACID 50% in water w/w + 4 g DIACETYL/ ACETOIN mixture 1/1 w/w 76 g WATER + 20 g solution of GLYOXILYC 30 60 210 (++++) (++++) (++++) (+++) (+++) (+++) ACID 50% in water w/w + 4 g DIACETYL/ ACETOIN mixture 10/1 w/w 76 g Unicompany COSMETIC BASE + 20 g 30 60 210 (++++) (++++) (++++) (+++) (+++) (+++) solution of GLYOXILYC ACID 50% in water w/w + 4 g DIACETYL/ACETOIN mixture 1/10 w/w PYRUVIC ACID 4 Molar 40 25 180 (+++) (+++) (++) (++) (+) (+/) (Example 3 of WO2007/135299 A1) Reduction Reduction Reduction Reduction No lower between between between Reduc- MEASURED PARAMETER effect than 25% 26 and 50% 51 and 75% 76 and 90% tion >90% % Reduction of number of curves found in 30 cm of hair +/ + ++ +++ ++++ (no. of residual curves/no. of initial curves 100)

(49) TABLE-US-00013 TABLE 7 European TYPE, NATURAL CURLY HAIR STRAIGHTENING EFFECT ASSESSMENT (curve reduction) Temp. Hair of hair fiber straight- after no. 1 after 2nd after 3rd after 4th after 5th after 6th temper- Contact ening shampoo shampoo shampoo shampoo shampoo shampoo ature time iron and and and and and and TEST PREPARATION ( C.) (minutes) ( C.) drying drying drying drying drying drying WATER 100 ml 30 60 210 () () () () () () 76 g WATER + 20 g solution of GLYOXILYC 30 60 210 (++++) (++++) (++++) (++++) (++++) (++++) ACID 50% in water w/w + 4 g DIACETYL/ ACETOIN mixture 1/10 w/w 76 g WATER + 20 g solution of GLYOXILYC 30 60 210 (++++) (++++) (++++) (++++) (++++) (++++) ACID 50% in water w/w + 4 g DIACETYL/ ACETOIN mixture 1/1 w/w 76 g WATER + 20 g solution of GLYOXILYC 30 60 210 (++++) (++++) (++++) (++++) (++++) (++++) ACID 50% in water w/w + 4 g DIACETYL/ ACETOIN mixture 10/1 w/w 76 g Unicompany COSMETIC BASE + 20 g 30 60 210 (++++) (++++) (++++) (++++) (++++) (++++) solution of GLYOXILYC ACID 50% in water w/w + 4 g DIACETYL/ACETOIN mixture 1/10 w/w PYRUVIC ACID 4 Molar 40 25 180 (++++) (+++) (++) (++) (+) (+/) (Example 3 of WO2007/135299 A1) Reduction Reduction Reduction Reduction No lower between between between Reduc- MEASURED PARAMETER effect than 25% 26 and 50% 51 and 75% 76 and 90% tion >90% % Reduction of number of curves found in 30 cm of hair +/ + ++ +++ ++++ (no. of residual curves/no. of initial curves 100)

(50) TABLE-US-00014 TABLE 8 AFRO TYPE, NATURAL CURLY HAIR VOLUME REDUCTION ASSESSMENT (reduction of hair spatial volume) Temp. Hair of hair fiber straight- after no. 1 after 2nd after 3rd after 4th after 5th after 6th temper- Contact ening shampoo shampoo shampoo shampoo shampoo shampoo ature time iron and and and and and and TEST PREPARATION ( C.) (minutes) ( C.) drying drying drying drying drying drying WATER 100 ml 30 60 210 () () () () () () 76 g WATER + 20 g solution of GLYOXILYC 30 60 210 (++++) (++++) (++++) (++++) (++++) (++) ACID 50% in water w/w + 4 g DIACETYL/ ACETOIN mixture 1/10 w/w 76 g WATER + 20 g solution of GLYOXILYC 30 60 210 (++++) (++++) (++++) (++++) (++++) (+++) ACID 50% in water w/w + 4 g DIACETYL/ ACETOIN mixture 1/1 w/w 76 g WATER + 20 g solution of GLYOXILYC 30 60 210 (++++) (++++) (++++) (++++) (+++) (++) ACID 50% in water w/w + 4 g DIACETYL/ ACETOIN mixture 10/1 w/w 76 g Unicompany COSMETIC BASE + 20 g 30 60 210 (++++) (++++) (++++) (+++) (+++) (++) solution of GLYOXILYC ACID 50% in water w/w + 4 g DIACETYL/ACETOIN mixture 1/10 w/w PYRUVIC ACID 4 Molar 40 25 180 (+++) (+++) (++) (++) (+) (+/) (Example 3 of WO2007/135299 A1) Reduction Reduction Reduction Reduction No lower between between between Reduc- MEASURED PARAMETER effect than 25% 26 and 50% 51 and 75% 76 and 90% tion >90% % Reduction of hair volume (circumference of lock with 1.0 g +/ + ++ +++ ++++ weight measured at half length) (test final diameter/initial diameter 100)

(51) TABLE-US-00015 TABLE 9 European TYPE, NATURAL CURLY HAIR VOLUME REDUCTION ASSESSMENT (reduction of hair spatial volume) Temp. Hair of hair fiber straight- after no. 1 after 2nd after 3rd after 4th after 5th after 6th temper- Contact ening shampoo shampoo shampoo shampoo shampoo shampoo ature time iron and and and and and and TEST PREPARATION ( C.) (minutes) ( C.) drying drying drying drying drying drying WATER 100 ml 30 60 210 () () () () () () 76 g WATER + 20 g solution of GLYOXILYC 30 60 210 (++++) (++++) (++++) (++++) (++++) (+++) ACID 50% in water w/w + 4 g DIACETYL/ ACETOIN mixture 1/10 w/w 76 g WATER + 20 g solution of GLYOXILYC 30 60 210 (++++) (++++) (++++) (++++) (++++) (++++) ACID 50% in water w/w + 4 g DIACETYL/ ACETOIN mixture 1/1 w/w 76 g WATER + 20 g solution of GLYOXILYC 30 60 210 (++++) (++++) (++++) (++++) (++++) (+++) ACID 50% in water w/w + 4 g DIACETYL/ ACETOIN mixture 10/1 w/w 76 g Unicompany COSMETIC BASE + 20 g 30 60 210 (++++) (++++) (++++) (++++) (+++) (+++) solution of GLYOXILYC ACID 50% in water w/w + 4 g DIACETYL/ACETOIN mixture 1/10 w/w PYRUVIC ACID 4 Molar 40 25 180 (++++) (+++) (++) (++) (+) (+/) (Example 3 of WO2007/135299 A1) Reduction Reduction Reduction Reduction No lower between between between Reduc- MEASURED PARAMETER effect than 25% 26 and 50% 51 and 75% 76 and 90% tion >90% % Reduction of hair volume (circumference of lock with 1.0 g +/ + ++ +++ ++++ weight measured at half length) (test final diameter/initial diameter 100)

(52) TABLE-US-00016 TABLE 10 AFRO TYPE, NATURAL CURLY HAIR EVALUATION OF STRAIGHTENING EFFECT (reduction of curves) with different contact time Temp. Hair of hair fiber straight- after no. 1 after 2nd after 3rd after 4th after 5th after 6th temper- Contact ening shampoo shampoo shampoo shampoo shampoo shampoo ature time iron and and and and and and TEST PREPARATION ( C.) (minutes) ( C.) drying drying drying drying drying drying WATER 100 ml 30 15 210 () () () () () () WATER 100 ml 30 90 210 () () () () () () WATER 100 ml 30 120 210 () () () () () () 76 g WATER + 20 g solution of GLYOXILYC 30 15 210 (+++) (+++) (+++) (++) (++) (+) ACID 50% in water w/w + 4 g DIACETYL/ ACETOIN mixture 1/1 w/w 76 g WATER + 20 g solution of GLYOXILYC 30 90 210 (++++) (++++) (++++) (++++) (++++) (++++) ACID 50% in water w/w + 4 g DIACETYL/ ACETOIN mixture 1/1 w/w 76 g WATER + 20 g solution of GLYOXILYC 30 120 210 (++++) (++++) (+++) (++++) (+++) (++) ACID 50% in water w/w + 4 g DIACETYL/ ACETOIN mixture 1/1 w/w 76 g Unicompany COSMETIC BASE + 20 g 30 15 210 (++++) (++++) (+++) (+++) (++) (+) solution of GLYOXILYC ACID 50% in water w/w + 4 g DIACETYL/ACETOIN mixture 1/10 w/w 76 g Unicompany COSMETIC BASE + 20 g 30 90 210 (++++) (++++) (++++) (++++) (+++) (+++) solution of GLYOXILYC ACID 50% in water w/w + 4 g DIACETYL/ACETOIN mixture 1/10 w/w 76 g Unicompany COSMETIC BASE + 20 g 30 120 210 (++++) (++++) (++++) (+++) (++) (++) solution of GLYOXILYC ACID 50% in water w/w + 4 g DIACETYL/ACETOIN mixture 1/10 w/w PYRUVIC ACID 4 Molar 40 25 180 (++++) (+++) (++) (++) (+) (+/) (Example 3 of WO2007/135299 A1) Reduction Reduction Reduction Reduction No lower between between between Reduc- MEASURED PARAMETER effect than 25% 26 and 50% 51 and 75% 76 and 90% tion >90% % Reduction of number of curves found in 30 cm of hair +/ + ++ +++ ++++ (no. of residual curves/no. of initial curves 100)