WO2008091076A1

WO2008091076A1 - Permanent cosmetic composition for two-step permanent operation

Info

Publication number: WO2008091076A1
Application number: PCT/KR2008/000310
Authority: WO
Inventors: Chaesung Lim
Original assignee: Chaesung Lim
Priority date: 2007-01-25
Filing date: 2008-01-18
Publication date: 2008-07-31
Also published as: KR100795588B1

Abstract

Disclosed is a permanent cosmetic composition for two-step permanent waving operation that comprises a first solution comprising a reducing agent, a thickener, an alkaline agent, an alcohol, a metal inhibitor and a reaction catalyst and a second solution comprising an oxidizing agent and a reaction catalyst. The remainder of the composition is selected from distilled water, ion exchanged water or far-infrared water. The permanent cosmetic composition for two-step permanent waving operation of the present invention involves a catalytic reaction. Hence, the reaction rate is improved up to 95 %, whereas the conventional permanent cosmetic composition for two-step permanent waving operation has the reaction rate of 60-70 %. Therefore, the permanent cosmetic composition for two-step permanent waving operation of the present invention greatly reduces hair damage, rapidly makes hair curl, remains no repulsive odors after hair washing, and maintains significant hair elasticity.

Description

PERMANENTWAVE SOLUTION

[DESCRIPTION]

[Technical Field]

The present invention relates to a permanent cosmetic composition for two-step permanent waving operation comprising improved solutions.

[Background Art]

The conventional permanent cosmetic composition for permanent waving operation has been used over 40 years since its development. Such permanent cosmetic composition mainly consists of a first solution comprising ammonium thioglycolate and caustic alkali or alkali carbonate, and a second solution which is practically an aqueous solution of hydrogen peroxide or alkali bromide.

The most widely accepted permanent waving based on theory is performed as follows.

When the first solution is applied to the hair, the disulfide bond (R- S-S-R) of cystine contained in keratin, a constituent of hair, is broken into R-S-H and R-S-H by hydrogenation reduction, making the hair softer so as to be curled or deformed easily. And then, when an oxidizing agent is applied to the hair as the second solution, the broken bond is re-bonded by oxidation as illustrated in the following Reaction Equation 1. Thus, the hair curls are stabilized.

Reaction Equation 1

R-S-H+H-S-R - Ur→I R-S-S-R+H₂ ^LO

Further, the conventional permanent wave solution is composed of a first solution containing an excess of an alkali compound (e.g., alkali carbonate, caustic alkali or ammonia water) that has an alkalinity of more than 4.5 as measured in the amount of 0.1 N HCl (niL) required for neutralizing 1 niL of the associated alkali. Therfore, upon application of the first solution onto the hair there is formed immediately a cyanide compound (e.g., potassium cyanide). This cyanide compound functions to break the disulfide bond (-S-S-) of cystine. More specifically, the reaction between cystine (R-S-S-R, where R represents keratin) and potassium cyanide (KCN) occurs in two steps as shown in the following Reaction Equation 2- Reaction Equation 2

R-S-S-K + KCN ^=* R-S-CK + K-S-R -(D R-S-CK + K-S-R_*==* R-S-R + K-S-CM-(I

As described above, this reaction produces lanthionine (R-S-R) and potassium thiocyanide (see C. R. Robbins, Chemical and Physical Behavior of Human Hair, Fragrance Journal, p. 56, 1982).

Subsequently, as shown in the following Reaction Equation 3, when using the second solution, thiocyanide (-SCN) is oxidized by alkali bromide, which is an oxidizing agent principally contained in the second solution. Even when the second solution is not used, cyanide (ferric cyanide), which is a byproduct in the waste solution of the permanent wave solution, is oxidized to yield a cyanide compound.

Reaction Equation 3

-SCN+O₉->-CN+SO₉ 2 -(3)

As is well known in the art, the cyanide compound reacts with iron contained in hair to form a ferrous hexacyano compound (blue cyanide) or a ferric hexacyano compound (red cyanide).

Therefore, repeated use of a reducing agent with high alkalinity and a strong oxidizing agent results in de-coloration or damage to the hair as well as irritations to the skin when they are in contact with the skin. Further, repulsive odors are emitted, which remain for a long period of time, even after hair washing, thus causing discomfort. [Disclosure]

[Technical Problem]

Accordingly, it is an object the present invention to solve the problems with the prior art and to provide a permanent cosmetic composition for two-step permanent waving operation that eliminates the need for using a strongly alkaline reducing agent in the first solution and using a strong oxidizing agent in the second solution, utilizes a weak alkali and a weak oxidizing agent instead, reduces potential discomfort from contact with the skin, prevents hair damage, makes hair glossy and elastic without odor, and provides a pleasant operation condition for the permanent waving.

[Technical Solution]

In an embodiment, the present invention provides a permanent cosmetic composition for two-step permanent waving operation, which comprises a low pH first solution comprising a weak alkali and a low concentration of a reducing agent and a second solution comprising a weak oxidizing agent, which can be used at both low and elevated temperature.

[Best Mode]

The present invention provides a permanent cosmetic composition for a two-step permanent waving operation, which comprises a low pH first solution comprising a weak alkali and a low concentration of a reducing agent and a second solution comprising a weak oxidizing agent.

The first solution comprises a reducing agent, a thickener, an alkaline agent, an alcohol, a metal inhibitor, a reaction catalyst, and the balance of distilled water.

The reducing agent included in the first solution is preferably selected from the group consisting of thioglycolic acid, thioacetic acid, thioglycerol , acetylcysteine and cysteine, 1.0 to 5.0 weight %. When the content is less than 1.0 weight %, formation and maintenance of curls may be insufficient, due to insufficient reduction. And, a content in excess of 5.0 weight % may result in hair damage.

The thickener is preferably selected from the group consisting of carboxymethyl cellulose (CMC), hydroxypropylmethyl cellulose (HPMC), hydroxyethyl cellulose (HEC), polyacrylate (PA) and fumed silica, and is used in the amount of from 1.0 to 4.0 weight %.

The alkaline agent is preferably selected from the group consisting of mono-, di- or tri-ethanolamine, sodium hydroxide, potassium hydroxide, sodium carbonate and potassium carbonate, and is used in the amount of from 0.1 to 9.5 weight % such that the alkalinity is adjusted to 2.5 to 4.0.

The reaction catalyst included in the first solution is preferably selected from M-SCNs, inorganic compounds having a thiocyanide group, where M may be Na, K, Fe, Cu or NH₄, and is used in the amount of from 0.01 to 5.0 weight %.

The alcohol as used in the present invention is preferably selected from the group consisting of ethyl alcohol, propyl alcohol, benzyl alcohol and polyalcohol, and is used in the amount of from 1.0 to 15.0 weight %.

A metal inhibitor is used in order to prevent iron (Fe) contained in hair from reacting with the cyanide compound and forming iron cyanide compounds. The metal inhibitor as used in the present invention may be EDTA 2Na, and is preferably used in 0.1 to 1.0 weight %.

The second solution comprises an oxidizing agent and a reaction catalyst. The oxidizing agent is preferably selected from the group consisting of bromate, urate, super saturated acid salt and monopersulfate, and is used in the amount of from 1 to 20 weight %. And, the reaction catalyst is preferably selected from an inorganic compound M-SCN having a thiocyanide group, where M may be Na, K, Fe, Cu or NH₄, and is used in the amount of from 0.01 to 2.0 weight %.

The residual component of the composition of the present invention includes distilled water, ion exchanged water or far-infrared water. As used herein, far-infrared water refers to the water treated by irradiating far infrared ray, for the purpose of sterilization and improvement of oxidation- reduction reactivity.

The reaction of the permanent cosmetic composition for two-step permanent waving operation of the present invention with hair can be expressed as in Reaction Equation 4 below.

In the equation, K represents keratin, which can be expressed by Chemical Formula l:

Mercaptan is used as a reducing agent. Commonly used reducing agents are cysteine and thioglycolic acid, which are expressed by Chemical Formula 2:

Cysteine

CO₂H Thioglycolic acid

HO 2 ^~ C "CHg ^~ SH

Reaction Equation 4

K-S-S-K+2R-SH & R-S-S-R+2K-SH - (1)

K-S-S-K+R-SH o K-S-S-R+K-SH - (2)

K-S-S-R+R-SH <s> R-S-S-R+K-SH - (3)

In Reaction Equation 4, the reduction potential of mercaptan changes depending on pH, and the degree of reduction is proportional to pH above pH 6.0. Below pH 7.0, the reduction equilibrium constant of simple mercaptan (reducing agent) such as cysteine and thioglycolic acid is about 1.

._ .... . . _t [R-S-S-R][K-SHf

Equilibrium constant = r

[K-S-S-R][R-SH]²

The factors that may affect the reduction are as follows:

(1) pH greatly affects the reaction rate. At pH 7.0, reduction is the rate determining step.

(2) When pH is decreased to 2.0, reduction hardly occurs.

(3) Reduction by the reducing agent (mercaptan) occurs in alkaline pH (pH 9.0 to 9.5).

(4) At higher pH, the swelling rate of hair increases.

(5) A sufficient amount of mercaptan (reducing agent) needed for completely reducing disulfide contained in hair is required.

(6) When reduction is carried out using thioglycolic acid or cysteine at high concentration, molecular rearrangement may occur, rather than the exchange of a disulfide bond with the mercaptan group.

Accordingly, the strong alkaline solution, the one having an alkalinity of from 5 to 6 and pH of about from 9.4 to 9.6, included in the first solution of the conventional two-step permanent wave solution in order to improve reducing action and increase reaction rate, results in hair damage, skin irritations, and repulsive odors, which remain for a long period of time, even after hair washing, thus causing discomfort.

In order to solve this problem, in the present invention, the contents of the reducing agent and the alkaline agent are reduced to about half and the pH is maintained close to neutral pH, using a catalyst. As a result, in addition to solving the problem and overcoming the disadvantage of the conventional two-step permanent wave solution, the time required for permanent operation can be reduced significantly.

More specifically, when a cyanide compound is added during the reduction, reduction occurs regardless of pH and alkaline solution, as shown in Reaction Equation 5. That is, since R-SCN functions as reduction catalyst in the first solution, the reaction occurs smoothly even with a weak alkali and at low pH. Besides, the amount of mercaptan (reducing agent) can be decreased.

Reaction Equation 5

K-S-S-K+2R-SH <^> R-S-S-R+2K-SH - (1)

K-S-S-K+R-SH <=> K-S-S-R+K-SH - (2)

K-S-S-R+R-SH o R-S-S-R+K-SH - (3)

As for oxidation, the conventional two-step permanent wave solution required about 15 to 20 minutes of time, which resulted in severe hair damage by the oxidizing agent. In contrast, the -SCN group added to the first solution as reduction catalyst functions as oxidation catalyst, as shown in Reaction Equation 6. Consequently, the oxidizing agent can be used at lower content, and hair damage can be prevented since the time required for the oxidation is reduced to about 5 minutes.

Reaction Equation 6

{1 } Oxidation in sseoncj solution of conventional two-step waving solutic UK-SH -* K S S K -* K-S -S-K — »

I! o

(2) Oxdlαtion by oαuiyst -SCN

-SON - O₂ ^•> ^~CN »- SO₂ T

Herein below are preferred embodiments of the present invention illustrated with reference to examples and comparative examples, however, they should not be construed as limiting the scope of the present invention.

Examples 1 to 8: Preparation of a permanent cosmetic composition for two-step permanent waving operation of the present invention

The first solution and the second solution were prepared by using the common method, as described in Table 1 and Table 2. [Table 1]

First solution of permanent cosmetic composition for two-step permanent waving operation of the present invention (unit: weight %)

[Table 2]

Second solution of permanent cosmetic composition for two-step permanent waving operation of the present invention (unit: weight %)

Comparative Examples 1 and 2: Preparation of conventional permanent cosmetic composition for two-step permanent waving operation

Conventional permanent cosmetic composition for two-step permanent waving operation (Korean Patent No. 10-0648688) was prepared, as described in Table 3 and Table 4. Curl formation and maintenance, hair damage, and time required for permanent operation were compared with the compositions of the present invention. [Table 3]

First solution of conventional permanent cosmetic composition for two- step permanent waving operation (unit: weight %)

[Table 4]

Second solution of conventional permanent cosmetic composition for two- step permanent waving operation (unit: weight %)

Comparative Examples 3 and 4: Preparation of conventional permanent cosmetic composition for one-step permanent waving operation

Conventional permanent cosmetic composition for one-step permanent waving operation (Korean Patent No. 10-134755) was prepared by the common method, as described in Table 5. Curl formation and maintenance, hair damage, and time required for permanent operation were compared with the compositions of the present invention. [Table 5]

Conventional permanent cosmetic composition for one-step permanent waving operation (unit: weight %)

The comparison result is given in Table 6.

Curl performance (%) was evaluated by Kirby s method using a curling test apparatus, as follows. Swatches of 15 to 20 cm long healthy hair were fixed to the test apparatus and immersed in containers holding the compositions of Examples 1 to 8 and Comparative Examples 1 to 4 in a 25 C water bath. After being left for 20 minutes, the swatches of hair were washed, along with the apparatus, with running water, dried, and then fixed on a glass plate. Curl performance was calculated according to Equation 1:

Cυrlperfoπτiance (%) = 100- xIOO

(c-a) wherein a is the distance between the both ends of the test apparatus where the swatches of hair were fixed, b is the distance between 5 peaks of the curled hair, and c is the distance between the 5 peaks when the hair was straightened.

Hair damage was evaluated as follows. Onto 15 to 20 cm long decolorized hair, dyed hair and normal hair, the compositions of Examples 1 to 8 and Comparative Examples 1 to 4 were applied uniformly. The hair samples were wound around a rod with a constant force. After being left for 20 minutes, the samples were released from the rod, washed and dried. A hair beauty specialist performed a visual evaluation using a microscope on the damage of hair and the cortex layer. The evaluation criteria ranged from a score of 1 (no damage) to a score of 10 (severe damage).

Time required for permanent operation was measured based on the time from the application of the first solution, in case of the two-step waving composition, or the one-step waving composition, in case of the one-step waving composition, to winding and to washing after the curls were completed.

Curl maintenance was evaluated by performing permanent operations on 50 subjects and monitoring the number of days until the curls reduced to 50 % just after the operation.

Odors remaining after washing were evaluated after performing permanent operation and washing hair 1 to 3 times. A hair beauty specialist performed a sensory evaluation. The evaluation criteria ranged from a score of 1 (good or none) to a score of 10 (bad or severe). [Table 6]

Comparison of performance of composition of the present invention with conventional two-step and one-step compositions

As shown in Table 6, the permanent cosmetic composition for two-step permanent waving operation of the present invention exhibited superior result in curl performance and maintenance, which are directly associated with the reaction rate of the composition, compared with the conventional compositions. Further, the time required for permanent operation could be reduced to 30 minutes. In addition, hair damage decreased significantly and no odors remained even with a single washing, whereas they remain even after 3 washings in case of the conventional compositions. [Industrial Applicability]

As described above, the permanent cosmetic composition for two-step permanent waving operation of the present invention involves a catalytic reaction. Hence, the reaction rate is improved to 80-95 %, whereas the conventional permanent cosmetic composition for two-step permanent waving operation has the reaction rate of 60-70 %. As a result, the permanent cosmetic composition for two-step permanent waving operation of the present invention greatly reduces hair damage, rapidly makes hair curl, remains no repulsive odors after hair washing, and maintains significant hair elasticity. Therefore, it provides a pleasant operation condition for the permanent waving.

While the present invention has been described with reference to the particular illustrative embodiments, it is not be restricted by the embodiments but only by the appended claims. It is to be appreciated that those skilled in the art can change or modify the embodiments without departing from the scope and spirit of the present invention.

Claims

[CLAIMS] [Claim 1]A permanent cosmetic composition for two-step permanent waving operation, which comprises: a first solution comprising:

1.0 to 5,0 weight % of at least one reducing agent selected from the group consisting of thioglycolic acid, thioacetic acid, thioglycerol , acetylcysteine and cysteine;

1.0 to 4.0 weight % of at least one thickener selected from the group consisting of carboxymethyl cellulose (CMC), hydroxypropylmethyl cellulose (HPMC), hydroxyethyl cellulose (HEC), polyacrylate (PA) and fumed silica!

0.1 to 9.5 weight % of at least one alkaline agent selected from the group consisting of mono-, di- or tri-ethanolamine, sodium hydroxide, potassium hydroxide, sodium carbonate and potassium carbonate;

0.01 to 5.0 weight % a reaction catalyst selected from M-SCNs, inorganic compounds having a thiocyanide group;

1.0 to 15.0 weight % of at least one alcohol selected from the group consisting of ethyl alcohol, propyl alcohol, benzyl alcohol and polyalcohol ;

0.1 to 1.0 weight % of EDTA 2Na as a metal inhibitor; and the balance being filled with one selected from the group consisting of distilled water, ion exchanged water and far-infrared water, wherein the first solution has an alkalinity of from 2.5 to 4 and pH of from 7.5 to 9; and a second solution comprising:

1 to 20 weight % of at least one oxidizing agent selected from the group consisting of bromate, urate, super saturated acid salt and monopersulfate;

0.01 to 2.0 weight % of a reaction catalyst selected from M-SCNs, inorganic compounds having a thiocyanide group; and the balance being filled with one selected from the group consisting of distilled water, ion exchanged water and far-infrared water. [Claim 2]

The permanent cosmetic composition for two-step permanent waving operation of claim 1, wherein, in the reaction catalyst M-SCN, M is selected from the group consisting of Na, K, Fe, Cu and NHj.