KR20170050212A - Method of Measuring Hair Elasticity - Google Patents

Abstract

The present invention relates to a method of measuring hair elasticity and, more specifically, relates to a method of measuring hair elasticity using an angle where hair is tilted from a horizontal surface by gravity, a vertical distance from a horizontal surface, and a weight of the hair measured by fixating one end of the hair to a vertical surface. According to the method of measuring the hair elasticity, an accurate quantitative numerical value is able to be compared and analyzed as the hair elasticity is calculated by an equation in consideration with the weight of the hair and the vertical distance between a part where the hair is tilted from the horizontal surface in comparison with an existing method comparing and evaluating the elasticity of hair based on only an angle where hair is tilted from a vertical surface. In addition, in comparison with a method which requires to measure a large amount of hair samples several times to improve a reliability of a result of an existing stress-strain curve; the method of measuring the hair elasticity obtains an effect of reducing a required time and effort by calculating the quantitative numerical value using the equation. The method of measuring the hair elasticity includes a step of fixating one end of the hair to a vertical surface to be perpendicular, and a step wherein the hair is tilted from the horizontal surface by gravity.

Description

Method of Measuring Hair Elasticity [

More particularly, the present invention relates to a hair elasticity measuring method using an angle at which one end of a hair is fixed to a vertical plane and an angle at which the hair is inclined from the horizontal plane by gravity, a vertical distance from the horizontal plane, .

Hair is known to be damaged by friction, heat, physical cutting, perm, decolorization, dyeing, and sunlight. First, in the case of hair damage due to heat, the moisture is evaporated and dried by the heat generated in the dryer during drying after the hair washing, the hair is expanded and deformed, and the black hair is discolored to dark brown. In addition, bubbles begin to form in the cortex and water quality of the hair, and the elasticity of the hair is lost, and the hair epidermis melts. Second, hair damage caused by perm is caused by defective treatment of perm solution, lack of time, and when hair becomes weak, alkali remains in hair, or oxidant remains, keratin protein is denatured and melanin pigment is faded do. Third, oxidative decolorizing effect of melanin pigment due to hydrogen peroxide occurs in addition to alkaline agent as a decolorizing agent. Repeated exposure to bleaching agents in the short term may cause hair to swell and soften, or the hair epidermis may become twisted, resulting in bending and causing damage. Finally, the ultraviolet rays and ultraviolet rays of the sunlight damage the hair keratin protein or cause protein denaturation.

In general, the hair is composed of a keratin protein containing 14-18% of cysteine among 18 amino acids. These keratin proteins are a very strong protein in mild conditions, such as water or neutral solvents, but can easily be damaged by excessive physicochemical treatments such as combing, dry heat, dyeing, perming, and the like. In recent years, hair is damaged due to various physical, chemical, or environmental factors such as frequent perms, dyeing, etc., and the hair becomes rough and loses its gloss and becomes less flexible, and frictional force increases to make hair hard to be trimmed. There is a problem that hair tends to be thin and elasticity is lost, and there is no volume feeling as it is struck.

In order to solve these problems, there have been continuous researches on products for improving the flexibility of hair and for restoring and strengthening damaged hair after washing or washing, and various methods have been tried and developed and put into practical use. However, before developing a product for hair, there is no way to accurately quantify the shine, flexibility and elasticity of hair quantitatively.

Accordingly, the inventor of the present invention has completed the present invention by focusing on Hook's Law, which is a physical law relating to a force and a degree of deformation of a method for measuring the elasticity of hair to restore the original state of the elastic body.

Korean Patent Laid-Open Publication No. 2013-0031670 "Method for Measuring Amount of Hair Absorption of Silicon in Cosmetic Composition for Hair Using XRF"

Conventionally, a method of measuring the elasticity of hair is as follows. First, both ends of the hair are fixed to the tensile strength measuring instrument by a holder, and then a tensile stress is applied to obtain a stress-strain curve, and the elasticity (N / m) is obtained from this curve. This measure can quantitatively obtain elastic results at the same time as obtaining the tensile results, but it is not possible to take into account variables related to the mass, thickness and length of the hair, and therefore a large amount of hair samples must be measured several times in order to increase the reliability of the results . In addition, it is difficult to fix the hair to the tensile measuring instrument holder, and since the measurement time is relatively long, it takes a long time to measure several times with a large amount of hair samples.

It is an object of the present invention to derive the elasticity of hair to quantitative values, and another object of the present invention is to improve the reliability of results by deriving accurate measurement values while reducing the number of experiments.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems, and it is an object of the present invention to measure the elasticity of hair using an angle at which one end of the hair is fixed to a vertical plane and an angle at which the hair is inclined from the horizontal plane by gravity, . ≪ / RTI >

I) fixing one end of the hair perpendicular to the vertical plane; Ii) the hair is tilted from a horizontal plane by gravity; Iii) drawing a first tangent at the one end where the hair is fixed and a second tangent at the other end of the hair; Iv) drawing a perpendicular from the point where the extension line of the first tangent line and the extension line of the second tangent line meet with each other; V) measuring the vertical distance (y, meter (m)) from the feet of the waterline to the horizontal plane; (Vi) drawing a straight line from the foot of the waterline to one end of the hairline; (K), elastic modulus (N / m (m)) of the hair by the following equation (2) ) Is obtained by measuring the elasticity of hair.

Ky = mg · sin (90 ° -θ)

(Where m is the mass of the hair in kg and g is the gravitational acceleration in m / sec ² )

According to the hair elasticity measuring method of the present invention, compared with the conventional method of qualitatively comparing and evaluating the elasticity of the hair only at an angle inclined with respect to the vertical plane, considering the weight of the hair and the vertical distance at which the hair is inclined, The elasticity degree of the elastic member can be calculated through an equation, so that accurate quantitative values can be compared and analyzed.

Further, in comparison with a method in which a large amount of hair samples have to be measured several times in order to increase the reliability in the result of the conventional stress-strain curve, the present invention calculates the quantitative value through the equation, There is an effect that effort can be alleviated.

1 is an image of a method for measuring the elasticity of hair in the related art.
2 is a conceptual diagram of a method for measuring the elasticity of hair of the present invention.
3 is a conceptual diagram for applying the trigonometric function in the method of measuring the elasticity of the hair of the present invention.
FIG. 4 is an operation image for fixing the hair on a vertical plane in order to measure the elasticity of the hair, according to an embodiment of the present invention.
FIG. 5 is a view illustrating an operation image of imaging with a camera in order to measure the elasticity of hair, according to an embodiment of the present invention.
FIG. 6 is an operational image of applying the method of measuring the elasticity of hair of the present invention to an image imaged by a camera, according to an embodiment of the present invention.
FIG. 7 shows a normal distribution curve of a result obtained through a method of measuring the elasticity of hair according to an embodiment of the present invention. FIG.

More particularly, the present invention relates to a method of measuring the elasticity of hair by fixing one end of the hair to a vertical plane and using the angle at which the hair is inclined from the horizontal plane by gravity, the vertical distance from the horizontal plane, And to a method of measuring the same.

When the weight is suspended on the spring, the spring increases according to the weight of the weight. Thus, the deformation degree of the elastic body including the spring becomes proportional to the force to be restored to the original shape, that is, the elastic force. In this connection, Hooke's law assumes that the degree of deformation (x) of the elastic body due to the external force (mg) is directly proportional to the _elastic force (F _{elastic force} ) (1). In order to quantitatively derive the degree of elasticity of hair, the present invention applies Hooke's law applied to the elastic body.

&Quot; (1) " kx = mg

(Where m is the mass of the hair in kg and g is the gravitational acceleration in m / sec ² )

The 'elasticity' or 'elasticity' of hair in the present invention or the present invention is a characteristic of hair to support hair straight at right angles to the surface of the scalp. In the Hooke's law, the elastic coefficient 'k (Stiffness) And is different from the F _elasticity , which is the restoring force acting in the opposite direction of gravity in order to keep the hair perpendicular to the surface of the scalp. Therefore, the present invention attempts to measure the elasticity (elasticity) of hair by calculating the elastic modulus 'k' of the Hooke's law.

Also, the mass (m) or the weight (mg) of hair in the present invention or the present invention is a comprehensive concept including the mass or weight of the hair remaining on the sample to be tested, which is greater than the mass of the hair itself.

In addition, each numerical value applied to the present invention or the formulas in this specification is based on the SI basic unit system which is an international standard unit.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to preferred embodiments and accompanying drawings. In order to clarify the present invention, contents which are not related to the configuration of the present invention will be omitted, and the same reference numerals are used for the same components.

Conventionally, as shown in FIG. 1, only one angle of the hair is fixed by fixing the one end of the hair on the vertical plane, and the degree of the hair elasticity is predicted, and thus the quantitative result of the hair elasticity can not be presented. However, the present invention proposes a method of measuring the elasticity of hair by measuring both the vertical distance of the hair away from the horizontal plane and the weight value of the hair as well as the inclination angle of the hair, and applying it to the modified Hooke's law.

2, when one end a of the hair is fixed at right angles to the vertical plane V, the other end b of the non-fixed hair is moved by gravity The hair is tilted with respect to the horizontal plane H while being dropped. The first tangent line at one end (a) of the fixed hair and the second tangent line at the other end (b) of the curled hair are drawn in the tilted state, and a point (o) (Perpendicular). When the foot p of the waterline is determined, the shortest distance from this point to the horizontal plane H, that is, the vertical distance y, is measured in meters (m) A straight line is drawn up to the fixed one end (a), and the angle (?, Degree) formed by the straight line and the horizontal plane H is measured. The elasticity coefficient (k, elastic modulus (N / m)) of hair is quantitatively calculated by applying this to the following formula (2) of the present invention, which is based on the Hooke's law.

Ky = mg · sin (90 ° -θ)

(Where m is the mass of the hair in kg and g is the gravitational acceleration in m / sec ² )

In order to measure the elasticity of hair, the vertical distance from the point p at which the waterline descends at a point (o) where the extension lines of the first tangent line A and the second tangent line B meet each other y), but this is a measure of how far the hair is away from the horizontal plane (H) by gravity, and it is possible to set any point if the distance between the target hairs can be objectively compared. For example, in the present invention, the vertical distance 'y' may be the vertical distance from the midpoint (1/2 ab) of the total hair length ab to the horizontal plane (H).

FIG. 3 is a graph for explaining the reason why Equation (1) for measuring the elasticity of hair according to the present invention is modified from the law of Hook, assuming that the vertical plane V in FIG. 2 is the surface of the scalp, The angle between the surface (V) of the scalp and the hair (ap) is 90 ° because the hair (ap) perpendicular to the surface (V) of the scalp is inclined by ' ? -? '. In order to apply the law of the hook to the method of determining the elasticity of hair, the present invention introduces a sine function, and as the elasticity of the hair is excellent, the closer to 90 deg. (90 占 0)? 1. On the contrary, when the elasticity is low and the 90 ° -θ is close to 0 °, that is, as the θ converges to 90 °, sin (90 ° -θ) ≈0 becomes.

The procedure of < Example 1 > was carried out to verify the hair elasticity measuring method of the present invention.

&Lt; Example 1 >

Standard Hair (Manufacturer: Japan Beaulax Company ) Ready

Since the manufacturer manufactures a variety of hairs (actual human hair) to standard standards, the standard hairs used in this experiment can be applied alternatively to actual human hair.

Setting the number of hairs needed for one measurement

In order to measure the elasticity of hair of the present invention, one single strand or two to five multiple strands of hair can be used as a sample. However, since three or fewer hairs are statistically formed in a human scalp pore, . Hereinafter, the hair elasticity measurement test was carried out in three multiple strands in order to make it identical to human hair condition.

Resilience measurement

4 to 5 illustrate an embodiment of the present invention in which hair is fixed at right angles to a wall which is a vertical plane at one end of the three hairs so that the hair is pulled from the horizontal plane H by gravity Tilt. This state is imaged by a camera as shown in Fig. 6, a first tangent line is drawn from the starting point where the hair is fixed, and a second tangent line is drawn from the other end where the hair is not fixed, and a point at which the extension lines of the respective tangent lines meet with each other is determined . (Y) from the point at which the hair is fixed to the horizontal plane is measured, and the hair is fixed from the point to the horizontal plane And the angle (?) Formed by the straight line and the horizontal plane at the position where the hair is fixed is measured.

The measured results are as follows.

y = 0.01 m

θ = 30˚

m = 0.0000016 kg

Based on the measurement result, the elasticity degree (k) of the hair is obtained by applying Equation (2).

k = 0.167 mN / m

The process of increasing the elasticity of hair is as follows. The elasticity enhancing product (for example, elasticity shampoo) is processed to increase the elasticity of the hair. As a result, the active ingredient in the product penetrates and adsorbs to the inside / outside of the hair to increase the elasticity of the hair, and the efficacy components of the product It helps to hold it close to a right angle. The following tests were conducted in accordance with Example 2 to measure the elasticity of hair before and after the hair elasticity-imparted shampoo treatment as a hair elasticity product.

&Lt; Example 2 >

To evaluate the elasticity (k) according to the mass (m) or weight (mg) of hair, water treatment hair (control group), hair elasticity enhancing shampoo treated hair (test group 1) and hair elasticity enhancing shampoo treated hair The elasticity was measured by the hair elasticity measuring method using the test group 2) as a sample.

[Table 1]

Validation

Fig. 7 shows the result of the elasticity degree (k) value of Example 2 as a normal distribution curve through repeated experiments. It was confirmed that the elasticity of the hair was increased in the experimental group 1 and 2 treated with the elasticity enhancing shampoo, and that the elasticity of the hair was increased to within the error range by about 20 tests.

Hair has the same thickness, length, and shape even if it is obtained from the same Tress or from one person. Because the elasticity value is influenced by the shape of the hair, a single elasticity measurement experiment can not define the sample. Therefore, a large number of measurements are required and statistical normal distribution curves must be satisfied. The hair elasticity measuring method of the present invention was confirmed to satisfy the normal distribution curve by 20 experiments per one hair sample.

V. Vertical plane
H. Horizontal plane
A. First tangent
B. Second Tangent
y. Vertical distance the hair tilts from the horizontal plane
θ. The angle at which the hair tilts from the horizontal plane

Claims (4)

A method for measuring hair elasticity using an angle (?) In which one end of a hair is fixed to a vertical plane (V) and a hair is inclined from a horizontal plane (H) by gravity and a vertical distance (y) from a horizontal plane (H).
The method according to claim 1,
I) fixing one end (a) of the hair perpendicular to the vertical plane (V);
Ii) the hair is tilted from a horizontal plane (H) by gravity;
Iii) drawing a first tangent line (A) at one end (a) and a second tangent line (B) at the other end (b) of the hair;
Iv) drawing a perpendicular to the hair from a point (o) where an extension line of the first tangent line (A) and an extension line of the second tangent line (B) meet with each other;
(V) measuring a vertical distance (y, meter (m)) from the foot p of the waterline to the horizontal plane H;
(Vi) drawing a straight line from the pawl (p) to the one end (a) where the hair is fixed; And
(Ⅶ) measuring an angle (?, Degree (?)) Formed by the straight line and the horizontal plane (H);
Of the hair elasticity.
3. The method of claim 2,
(2) calculating elasticity (k, modulus of elasticity (N / m)) of hair by the following equation (2);
A hair elasticity measuring method further comprising:

Ky = mg · sin (90 ° -θ)
(Where k is the elasticity of the hair, m is the mass of the hair (kg), g is the gravitational acceleration (m / sec ² ), and y and θ are as defined in claim 2)
The method according to claim 1,
Wherein the hair is one single strand or two to five multiple strands.

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