JP2009160139A - Sensor for hair surface characteristics - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To evaluate hair surface characteristics corresponding to what we feel when we touch our hair surface such as being loose, stiff, grating, rustling, smooth, moistened, etc. in an objective, highly sensitive and well reproducible way. <P>SOLUTION: The sensor 1 for hair surface characteristics is provided with a sliding part 2, and a piezoelectric device 3 to detect the vibrations of the sliding part 2. The sliding part 2 should have a sliding surface that makes it contact the hair, slides on its surface and causes stick slips there, preferably a sliding surface with a surface tension of 25 mN/m or higher. The system 100 for hair surface characteristics evaluation includes a detection means 30 to detect vibrations by stick slips from a vibration signal output from the piezoelectric device 3 of the sensor 1. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a hair surface property sensor, a hair surface property evaluation system, and a hair surface property evaluation method.

  The touch that is felt by people when touching their hair with their fingers or palms is the important factor for judging the condition of hair as well as luster, such as softness, firmness, creaking, smoothness, smoothness and moisture. In the development of hair cosmetics, techniques for improving the feel of hair have become important.

  As a hair touch measurement technique, there is a Kawabata evaluation system (Non-patent Document 1). This system is a friction measuring instrument originally developed to measure the texture characteristics of fibers and fabrics, and requires 2 cm × 5 cm (sliding actual area) as the size of the object to be measured. For this reason, when evaluating the surface friction characteristics of hair, 10 to 100 hair fibers are arranged in parallel and fixed on a flat metal plate, and designed exclusively with a constant pressing pressure from the top of the hair. The surface friction characteristics of the hair are evaluated by sliding the slider and measuring the force required for sliding at this time.

  This system is useful for measuring hair properties in a laboratory. However, the work of arranging about 10 to 100 hairs in parallel in a predetermined area in order to secure the actual sliding area takes about 1 hour even if it is performed by a skilled person. In addition, the subject is burdened with having to cut hair. In addition, the measurement status of hair characteristics with this system is very different from the actual acquisition of the feel of touching the hair on the head with your hand. In addition, in order to detect subtle differences in the characteristics of the hair surface, much labor and time are required for the analysis process.

  On the other hand, an organic material piezoelectric element (polyvinylidene fluoride) (Patent Document 1) has been developed, and this superior processability is used to recognize a particularly fine difference in touch among finger sensory receptors. There is a hair tactile sensor developed with reference to the pachinko body (Non-Patent Document 2). However, even with this hair touch sensor, as with the Kawabata evaluation system, a large number of hairs are arranged in parallel, and the contact pressure when the surface is slid with a constant load is detected with a piezoelectric element. It is difficult to measure the evaluation of the feeling that a person feels when the person touches the hair on the head with his / her hand while only obtaining amplitude data of the contact pressure when the hair fiber is slid.

  In addition, there is a technique for evaluating comb-like or the like in a manner similar to combing hair with a comb (Patent Documents 2 and 3). However, the device used here is basically a device that measures the friction sound when combing hair with a comb or a comb-like object, and analyzes the comb and the like. For this reason, although the data measured by this apparatus includes data that correlates with the touch felt by humans, it is difficult to measure the touch such as rustling, wrinkle, squeak, smooth, smooth, moist.

  In addition, a method using a pulley (Non-Patent Document 3) has also been proposed for measuring the surface friction of hair. According to this method, although it is possible to measure friction with a single hair, it is necessary to cut out the hair for measurement, and it is necessary to obtain data on a large number of hairs for statistical processing. Burden the person.

JP 2006-52956 A JP-T-2004-527730 JP 2006-223853 A Hirono Kawano et al., “Effects of environmental changes on physical properties of hair”, J. Cos. Cosmet. Chem. Jpn., 33 (4), p377-385 (1999) SGUSEIDO NEWS RELEASE “Shiseido and Tohoku University have jointly developed a“ hair tactile sensor ”that can measure how you feel when touching hair”, [online], search January 11, 2007, Internet < URL http://www.shiseido.co.jp/releimg/1321-j.pdf> Teruo Horiuchi et al., J. Soc. Cosmet. Chem. Jpn., 14, 62-65 (1980)

  SUMMARY OF THE INVENTION An object of the present invention is to objectively evaluate the surface characteristics of hair corresponding to touches such as rustling, tackiness, creaking, smoothness, smoothness, and moistness that humans feel with high sensitivity and high reproducibility.

  For the above-mentioned purpose, the present inventor is effective to detect and analyze stick-slip that occurs in hair that has been damaged on the surface by a hair dye, a permanent agent or the like. It has been found that rubbing the hair between the sliding part having a value and the fingertip is particularly effective.

  Here, stick slip refers to continuous fine catches that are repeatedly felt when one to several hairs damaged on the surface by a hair dye, a permanent agent or the like are rubbed with a fingertip. That is, when rubbing hair with fingers, at the beginning of rubbing, it is necessary to apply a force greater than the maximum static frictional force between the fingertip and the hair, and thereafter, if the surface condition of the hair is constant, the maximum static frictional force It is possible to continue to slide the hair with a smaller dynamic friction force, but if the coefficient of dynamic friction between the fingertip and the hair increases at a certain part of the hair surface, it will slide with the force applied to the previous sliding. No longer. When the sliding stops, it does not slide again until a force greater than the maximum static frictional force at that portion is applied, and it gets caught. However, if a force greater than the maximum static friction force is applied, the fingertip slides on the hair all at once, and the force applied to the hair weakens, but if the force falls below the dynamic friction force, it will not slide again, and the maximum static friction force It is in a state of being caught until the above force is applied. Thus, the phenomenon that repeatedly causes a catch is called stick-slip.

  It has been common general knowledge that stick-slip is not preferable in measuring physical properties such as frictional force, but the present inventor dared to cause stick-slip and observe its vibration state. Surprisingly, it has been found that subtle changes in the surface properties of hair can be measured with high sensitivity, and the present invention has been completed.

  That is, the present invention provides a hair surface characteristic sensor that includes a sliding portion and a piezoelectric element that detects vibration of the sliding portion, causes the stick to slip by abutting the sliding portion against the hair and sliding the hair surface. I will provide a.

  The present invention also provides a hair surface characteristic sensor comprising a sliding part that slides on the hair surface and causes stick slip, and a piezoelectric element that detects vibration of the sliding part, and a piezoelectric element of the hair surface characteristic sensor Provides a hair surface characteristic evaluation system provided with detection means for detecting vibration caused by stick-slip from the sliding signal output from the.

  Furthermore, the present invention slides the hair surface with a sliding part to cause stick slip, detects vibration of the sliding part with a piezoelectric element, and detects stick-slip vibration from a sliding signal output from the piezoelectric element. And an evaluation method for evaluating the surface characteristics of the hair based on vibration of the stick-slip.

  Here, the hair may be either head hair or body hair, human hair or animal hair, hair separated from a living body such as tres, or a state of growing in the living body. Any of hair may be sufficient.

  According to the hair surface characteristic sensor of the present invention, not only the hair collected from the head and body but also the hair on the head and body can be measured. In addition, it does not rely on chemical methods such as surface composition analysis, and even if it is not an expert, it feels like a rustling, stiff, creaking, smooth, smooth, moist, etc. It becomes possible to output a sliding signal or the like as an index.

  Moreover, according to the hair surface characteristic evaluation system and evaluation method of the present invention, vibration due to stick slip can be detected and analyzed from a sliding signal obtained by sliding hair with a hair surface characteristic sensor.

  Furthermore, according to the hair surface property evaluation system and the evaluation method of the present invention, it is possible to easily analyze the hair surface property that is an index of touch such as softness, wrinkle, creaking, smoothness, slipperiness, moistness, etc. Subtle differences in characteristics can be analyzed.

  Hereinafter, the present invention will be specifically described with reference to the drawings. FIG. 1 is a configuration diagram of a hair surface property evaluation system 100 according to an embodiment of the present invention, which includes a hair surface property sensor 1 and a detection means 30. FIG. 2 is an exploded view of the hair surface characteristic sensor 1, and FIG.

  The hair that can be measured by the hair surface characteristic evaluation system 100 is human or animal head hair or body hair, and the hair may be separated from the living body as in the case of tres or may be in a living state. . From the viewpoint of evaluating the surface characteristics related to the damage received on the hair surface by a hair dye, a permanent agent, etc., it is highly significant that human hair, particularly the hair of a human being on the head, can be measured.

  Further, from the viewpoint of measurement accuracy and workability, the length of the hair to be measured is preferably 1 cm or more, more preferably 2 cm or more, and further preferably 3 cm or more.

  As shown in FIG. 3, the hair surface property sensor 1 is attached to the fingertip when measuring the surface property of the hair, and the hair S is picked by the other finger and the hair surface property sensor 1, and the root side of the hair S is picked while being picked. 1 to 2, and detects vibration during sliding. As shown in FIGS. 1 and 2, the sliding portion 2, the piezoelectric element 3, the vibration absorbing material 4, and the pressure sensor 5 are included. . Lead wires 6 come out of the piezoelectric element 3 and the pressing pressure sensor 5 and are bundled. Moreover, this hair surface characteristic sensor 1 is attached to the mounting tool 20 for mounting it on a fingertip.

  The sliding portion 2 is a member that directly contacts the hair when measuring the surface characteristics of the hair. The sliding portion 2 may be the surface member itself of the piezoelectric element 3, but is preferably provided separately from the piezoelectric element 3 from the viewpoint of durability of the piezoelectric element 3.

  The material for forming at least the sliding surface of the sliding portion 2 enables stick slip to occur when sliding with the hair. In particular, the stick slip occurs on hair whose surface has been damaged by a hair dye or a permanent agent. From the viewpoint of facilitating the occurrence, the surface tension value of the sliding portion is 25 mN / m or more, preferably 30 mN / m or more, and more preferably 35 mN / m or more.

Here, the surface tension refers to a critical surface tension γc generally used as an indicator of wettability of the surface of a solid substance. The specific material of the preferred sliding part (the value in parentheses is the surface tension value) is polypropylene (25.8 mN / m), polyethylene (28.1 mN / m), vinyl chloride resin (35 to 39 mN / m), Acrylic resin (39-40mN / m), nylon (44m ³ N / m), polyvinyl alcohol (55mN / m), glass (73mN / m), gold (1120mN / m), iron (1720mN / m), aluminum ( 1909 mN / m) and the like. In general, polytetrafluoroethylene (18.3 mN / m) and silicone (20 mN / m), which are widely used as a material for forming sliding parts, are less likely to cause stick slip even on hair with damaged surfaces. It is not preferable.

  The sliding portion 2 is a portion having an R value of 30 μm or less, preferably 40 μm or less, particularly 50 μm or less on the sliding surface of the sliding portion 2 from the viewpoint of preventing the hair from being damaged when sliding on the hair surface. It is preferable not to exist. From the viewpoint of ease of use, as shown in FIG. 4A, the sliding portion 2 has (a) a cylindrical shape, (b) an elliptical column shape, (c) a conical shape, (d) an elliptical cone shape, and (e) a square shape. Other polygonal columnar shapes such as a columnar shape, (f) a trapezoidal columnar shape, (g) a triangular columnar shape, (h) a saddle type can be used. Moreover, as shown to (i) and (j) of FIG. 4B, you may comprise the sliding part 2 by arranging a some columnar member. Among these, from the viewpoint of preventing the hair to be measured from being damaged, a shape in which chamfered corners having an R value of 0.1 mm or more are present in a line shape is preferable on the sliding surface, and a cylindrical shape is particularly preferable among them. On the other hand, from the viewpoint of preventing the hair to be measured from falling off during measurement by taking a large area of the sliding surface, as shown in FIG. 4C, the sliding surface 2a of the sliding portion 2 is a flat surface. It may be made to become.

  As shown in FIGS. 4A to 4C, when the sliding portion 2 is provided as a separate member from the piezoelectric element 3, the sliding portion 2 may be directly fixed to the piezoelectric element 3 with an adhesive or the like. Alternatively, it may be indirectly fixed via another member.

  On the other hand, the piezoelectric element 3 is an element that generates a voltage when a force such as vibration or pressure is applied, and includes a vibration plate or an electrode and a piezoelectric body such as ceramics. In the hair surface characteristic sensor 1, the piezoelectric element 3 has a function of converting vibration when the hair S is slid by the sliding portion 2 into a sliding signal.

  As the piezoelectric element 3, various materials and shapes can be used. From the viewpoint of reliably detecting a frequency region generated by stick-slip, 50 Hz to 3000 Hz when the maximum sensitivity is 0 dB, preferably It is preferable to have a sensitivity of −60 dB or more in the entire region of 40 Hz to 5000 Hz, and further 30 Hz to 10,000 Hz.

Area of the piezoelectric element 3, and the viewpoint of easily obtaining good sensitivity in the aforementioned frequency range, from the viewpoint of easily performing the measurement of the hair surface properties, preferably 0.8～80Cm ^2, further 1～50Cm ^2, Particularly, it is 1.2 to ²⁰ cm ² . Here, the area of the piezoelectric element means the largest area among the diaphragm or electrode and the piezoelectric body.

  Preferred piezoelectric elements that can be used in the present invention include, for example, PKS1-4A1, PKS1-4A10, PKS1-4B1, 6CC-21-15-700, 6CC-10-3R9-1000, 7D-25-1600, 7D. -15-5400 (Murata Manufacturing Co., Ltd.), M12SA1, M122A2, D131A1, D201B1A, M202B2, M204B4, M204B4A, M253B4A, M272C2, M274C4, M312C2A, M352D2A, M202B4, M202B2, F202 FM325D5, FM355D5, FM356D6 etc. (above made by Nippon Ceratech), EE series, EF series and OSF series (above) DK), disk-type piezoelectric elements D-4, D-5, D-10, W-40, Dt-10, M-20, M-22, etc., RP and RC series which are vibration pickup elements (and above) MKT Taisei Co., Ltd.), Nippon Ceratech Co., Ltd., and receiver piezoelectric elements such as MR-15-S02 (manufactured by Nihon Ceratech Co., Ltd.) provided as piezoelectric receivers.

  The vibration absorbing material 4 prevents the piezoelectric element 3 from generating unnecessary contact pressure signals generated by the distortion of the piezoelectric element 3 due to the movement of the finger joint or the movement of the lead wire 6. Is provided on the surface opposite to the sliding portion 2. As the vibration absorbing material 4, foamable rubber, silicone rubber, foamable plastic, highly elastic rubber, or the like can be used. The thickness of the vibration absorber 4 is preferably 0.1 to 3.0 mm from the viewpoint of absorbing unnecessary signals and facilitating measurement.

  The pressure sensor 5 detects the pressure when the hair is picked with the hair surface property sensor 1 and the finger, separately from the piezoelectric element 3, when measuring the surface property of the hair. By sequentially detecting and monitoring this pressing pressure, measurement of the surface characteristics of the hair is started when the pressing pressure reaches a predetermined pressure, and if the pressing pressure deviates from the predetermined range during the measurement of the surface characteristics, the measurement is repeated. It is possible to take countermeasures such as performing correction or correcting the measurement result. Therefore, the surface pressure can be measured with higher accuracy by the pressure sensor 5.

The pressure sensor 5 is 20 to 200 g / cm ² , preferably 30 from the viewpoint of detecting pressure that causes stick slip during measurement of the surface characteristics of the hair and does not cause damage such as cutting to the hair by the measurement. Those capable of detecting a pressure region of ˜150 g / cm ² are preferred.

  The type of the pressure sensor 5 is not particularly limited, and a commercially available sensor can be used, and a sensor that detects a change in capacitance, a sensor that detects a change in electrical resistance, and a distortion of a diaphragm. Things can be adapted. For example, a tactile sensor, a flexiforce button sensor, etc. manufactured by Nitta Corporation can be used.

  As a specific configuration of the pressing pressure sensor 5, for example, as shown in FIG. 2, two copper electrodes 7a and 7b (which are provided with electrodes having a predetermined shape on the surface of a general printed wiring board) are used. It is possible to use a sheet that can detect a change in electrical resistance by sandwiching the sheet 9. In this case, the conductive plastic sheet 9 preferably has a surface electrical resistance value of 10 kΩ or less, and for example, 20-30% carbon black is kneaded into polyethylene and molded into a sheet shape. As a commercially available product of the conductive plastic sheet 9, for example, a conductive bag F-15-A manufactured by Hozan Co., Ltd. can be used.

  In this pressing pressure sensor 5, if the relationship between the electrical resistance between the electrodes 7a and 7b and the pressure is obtained in advance, the pressing pressure can be known by measuring the electrical resistance between the electrodes 7a and 7b. In FIG. 2, reference numeral 8 a is a film substrate that supports the electrode 7 a on the piezoelectric element 3 side, and can be a substrate portion of a printed wiring board made of polyimide, for example. Specific examples of the printed wiring board include a flexible photosensitive substrate. Reference numeral 8b is a rigid substrate such as a glass epoxy substrate, a glass composite, or a bakelite that supports the other electrode 7b, and a spacer 10 (for example, a space is provided on the peripheral portion of the substrate 8b to secure a space. , A non-conductive plastic sheet having a thickness of 0.3 to 0.5 mm).

  The hair surface property sensor 1 is preferably provided with an attachment tool 20 in order to stably attach it to the fingertip or hand. The illustrated wearing tool 20 is made of a band-like member bonded to the lower surface of the substrate 8b, and is configured so that the hair surface characteristic sensor 1 can be worn on a finger having an arbitrary thickness with a hook-and-loop fastener. The wearing tool 20 is not limited to this, and it is sufficient that the hair surface property sensor of the present invention can be fixed to the fingertip or hand during measurement. For example, a finger sack made of an elastic material may be used.

  As a method of using the hair surface characteristic sensor 1, it is preferable to slide the hair surface characteristic sensor 1 attached to the fingertip as shown in FIG. The hair S is sandwiched between the part 2 and the abdomen of the finger not wearing the hair surface property sensor 1, and is used by sliding on the hair with a predetermined pressing pressure. In this case, the hair S is not limited to the hair collected from the head, but may be hair that has flung on the head.

  The number of hairs to be picked at a time is 1 to 10, preferably 1 to 5, more preferably 1 to 3, particularly 1 in terms of simple and reliable detection of the sliding signal of each individual hair. It is preferable.

  The sliding speed of the hair surface property sensor 1 may be constant or may vary. The sliding speed is in the range of 0.5 to 10 cm / sec, preferably 0.7 to 8 cm / sec, more preferably 1 to 5 cm / sec from the viewpoint of facilitating stick-slip and operability. preferable. Further, measurement may be performed by wearing a finger sack or gloves from the viewpoint of preventing the influence of the state of the fingertip not wearing the hair surface property sensor 1, for example, the sweating state, and suppressing the variation in the measured value by a person. .

In addition, as a usage method of the hair surface characteristic sensor 1, including the above-mentioned method,
1. Method of sliding the hair surface with the hair S sandwiched between the sliding part 2 and the fingertip
2. A method of picking the tip of the hair on the scalp with one hand and sliding the hair surface characteristic sensor 1 with the other hand against the hair surface.
3. A method of sliding the surface of the tres with one end fixed
4. A method of sliding hair stretched between arbitrary jigs at the sliding part.

  Further, when sliding, it is preferable to slide from the root side to the hair tip from the viewpoint of easily causing stick slip depending on the direction of the cuticle.

  The detecting means 30 detects vibration caused by stick-slip from a sliding signal output from the piezoelectric element 3 by sliding the sliding portion 2 of the hair surface characteristic sensor 1 on the hair. It can be configured by installing frequency analysis software that implements a frequency analysis algorithm using transformation, a wavelet analysis algorithm, or the like. The detection means 30 is not necessarily provided in the vicinity of the hair surface characteristic sensor 1. For example, a sliding signal is transmitted from the hair surface characteristic sensor 1 to the detection means 30 using communication means such as the Internet. May be.

  As a specific analysis method of the sliding signal in the detection means 30, for example, frequency analysis such as Fourier analysis is performed on a periodic and strong pulse in a chart in which sliding voltage is plotted against time. The frequency range where periodic and strong pulses are generated varies depending on the hair surface condition, sliding speed, surface tension of the sliding part, pressure, wetness of the finger surface used during measurement, greasy, etc. Periodic and strong pulses are generated in the region of 30 Hz to 10000 Hz, preferably 40 Hz to 5000 Hz, particularly 50 to 3000 Hz, which corresponds to the region where the stick-slip phenomenon occurs. Stick-slip is likely to occur when the hair surface is hydrophilized with a hair dye or a permanent agent, but it becomes difficult to occur when a hair is made hydrophobic by using a styling agent, a conditioner, a rinse, or the like. Therefore, against the vibration of healthy hair, it can be evaluated that the periodicity pulse due to the stick-slip phenomenon is strongly detected on the hair to be measured, and that the feeling of damage such as softness and stiffness is strong, On the contrary, the absence of such a periodic pulse can be evaluated as being moist and smooth.

  In addition, it is preferable that the periodic pulses are integrated and detected in an arbitrary range in the above-described frequency region where a periodic and strong pulse is generated by stick-slip. Accumulate periodic pulses to measure hair surface characteristics without blurring, such as clearly identifying the boundary between healthy and damaged parts of the hair, regardless of the hair surface condition, sliding speed, or person being measured. can do.

Example 1
(1) Production of hair surface property sensor The hair surface property sensor 1 of FIG. 1 was produced as follows. That is, for the sliding portion 2 that comes into contact with the hair, an acrylic material having a diameter of 3 mm (surface tension of 40 mN / m) cut into a length of 6 mm was used. As the piezoelectric element 3, a ceramic piezoelectric element having a diameter of 17 mm manufactured by Murata Manufacturing Co., Ltd. was used. As the vibration absorbing material 4, a product having a product name of sorbosein, a thickness of 3 mm and a hardness of S was cut into 15 mm × 15 mm. As the pressing pressure sensor 5, a flexible photosensitive substrate manufactured by Sanhayato Corporation is used, and a circular copper electrode 7a having a diameter of 8 mm and a thickness of 35 μm is provided on a polyimide film 8a having a thickness of 50 μm. A conductive plastic sheet 9 (thickness 0.1 mm) in which 20 to 30% carbon black is kneaded with a 1.6 mm thick glass epoxy substrate 8 b for circuit and a copper electrode 7 b having a diameter of 8 mm. A material having a surface electric resistance of 10 kΩ or less sandwiched therebetween was used. Epoxy adhesives and cyanoacrylate instant adhesives were used in place for bonding each part.

(2) Determination of pressing force for measuring surface characteristics with a hair surface characteristic sensor The hair surface characteristic sensor 1 prepared in (1) is attached to a finger, the hair S is sandwiched as shown in FIG. The pressing force was measured by the piezoelectric element 3 and the resistance value between the two electrodes 7 a and 7 b of the pressing pressure sensor 5 was measured. This measurement was carried out in several ways depending on whether the paneler pinched the hair lightly or strongly.

The results are shown in FIG. From FIG. 5, the pressing pressure was in the range of 50 to 250 g / cm ² , and the resistance value of the pressing pressure sensor 5 was changed in the range of 0.1 kΩ to 0.4 kΩ. In addition, when the value of the pressing pressure that a person usually feels when pinching hair was measured with an electronic pan balance (Metric Japan SCS-240) being sandwiched, it was about 100 g / cm ² . Therefore, in the subsequent measurement of the surface characteristics of normal hair, the measurement was performed when a resistance value corresponding to a pressing pressure of around 100 g / cm ² was detected by the pressing pressure sensor 5.

(3) Relationship between the surface tension of the sliding part and the pressing pressure at the time of measurement The material of the sliding part of the hair surface characteristic sensor 1 prepared in (1) is replaced with acrylic (surface tension 40 mN / m) and Teflon (registered) (Trademark) (surface tension 18mN / m), polyethylene (surface tension 28mN / m), glass (surface tension 73mN / m), aluminum (surface tension 1900mN / m) changed to each hair surface characteristic sensor As shown in FIG. 3, the hair S is sandwiched using 1 and slid against the hair at various loads at a speed of 2 cm / sec. The obtained signal is taken into a personal computer, and any commercially available frequency analysis software is used. Thus, the presence or absence of stick slip was observed depending on whether or not a periodic signal was detected in the 50 to 300 Hz region. In order to eliminate the influence of differences between people, all the series of measurements were performed by the same person.

  In this case, the hair used for the measurement was two types of lightly damaged hair and severely damaged hair obtained by the following treatment.

(i) Mildly damaged hair Hair of a 22-year-old Japanese woman without experience in color treatment and perm treatment was collected and used at room temperature with 1 g of a liquid mixture of 1 part / 2 parts prescribed ratio of Prettyia Soft Bubble Color manufactured by Kao Corporation. The treatment for the lower 20 minutes was performed once. Next, use plain shampoo (pH 6.8 to 7.2 containing 15% by weight of polyoxyethylene lauryl ether sodium sulfate, viscosity 40 to 100 mPa · s) so that you don't damage your hair. Let dry naturally. This was a mildly damaged hair.

(ii) Severely Damaged Hair On the other hand, a series of treatments for obtaining the above-mentioned mildly damaged hair was repeated 5 times to obtain severely damaged hair.

  The result of mildly damaged hair is shown in FIG. 6A, and the result of severely damaged hair is shown in FIG. 6B. The same measurement was performed three times, and the case where the occurrence of stick-slip was detected in all three times was shown as ◯, and the case where the occurrence of stick-slip was not detected even once was shown as x.

Thus, in order to stably generate the stick-slip phenomenon in hair damaged by color treatment, the surface tension of the sliding part is 30 mN / m or more at a pressure of 30 g / cm ² or more in the case of lightly damaged hair. In the case of severe damage, it was found that the surface tension of the sliding part was 25 mN / m or more at a pressure of 25 g / cm ² or more.

(4) Surface properties of healthy hair and color-treated hair One hair (length: 20 cm) of a 22-year-old Japanese woman who has no experience with color treatment and perm treatment was collected, and only 6 cm of the hair tip was pretia manufactured by Kao Corporation. Color treatment was carried out by carrying out the treatment for 20 minutes at room temperature once using 1 g of a mixture of soft foam color 1 agent / 2 agents. For hair that has undergone this color treatment once, do not damage the hair with plain shampoo (pH 6.8 to 7.2 containing 15% by weight of sodium polyoxyethylene lauryl ether sulfate, viscosity 40 to 100 mPa · s). Carefully rinsing with water while tracing with a finger, it was washed naturally. This washing processing cycle was performed 20 times to obtain a color processing unit.

  Using the hair surface property sensor 1 prepared in (1), the feel of this single hair was measured from the root side to the hair tip side. The result of frequency analysis of the obtained signal is shown in FIG. In this example, stick slip occurred between the hair and the hair surface property sensor 1 in the color processing unit, and a strong signal was observed in the region of 100 to 300 Hz in the portion corresponding to the color processing unit. As a result, it was confirmed that the determination of the color processing unit and the non-color processing unit can be performed very easily.

(5) Change in sliding speed and measurement results Similar to (4), color the hair ends, prepare washed hair, and use this hair surface property sensor 1 prepared in (1). One feel was measured from the root side to the hair tip side.

  In this case, the sliding speed was slowed at the color processing portion of the hair end. The result of frequency analysis is shown in FIG. As indicated by the arrows in the figure, it was found that the frequency at which a strong signal appears decreases as the sliding speed changes.

  FIG. 9A shows the results obtained by integrating the signals between 50 Hz and 200 Hz in the result of FIG. 8 and plotting the integrated values on the vertical axis, and FIG. 9B showing the same plot of the signals at 100 Hz. . From these figures, even if there is a change in the sliding speed by sliding the hair surface characteristic sensor 1 by hand, by carrying out strength analysis in a certain frequency range with respect to the frequency analysis result, color It was confirmed that the processing unit and the non-color processing unit can be easily and accurately identified.

Comparative Example 1
As shown in FIG. 10, measurement of hair whose hair ends are color-processed using a conventional sliding sound measuring device 40 having a commonly used plastic comb as a sliding portion 42 and a microphone 43 attached thereto. Went.

  However, in this comb-shaped sliding sound measuring device 40, since measurement with one hair is impossible, a hair bundle having a length of 20 cm and a width of 3 cm is formed, and about 10 cm in the lower half of the hair bundle (4 ), And after hair washing and drying, measurements were taken in a room at room temperature of 23 ° C. and humidity of 45%. Although the measurement was performed three times in succession, there was no significant difference between the color processing part and the non-color processing part.

  Of the three measurements, the second data was subjected to frequency analysis. The result is shown in FIG. From the figure, it cannot be said that there is a periodic and strong signal in the color processing unit relative to the uncolored processing unit, and the occurrence of stick-slip was not recognized.

  According to the hair surface property sensor of the present invention, it is possible to mechanically measure the feeling that a person feels when touching the finger with a finger or palm with high sensitivity and reproducibility. It is useful as a health counseling and hair cosmetic sales promotion tool.

It is a block diagram of a hair surface characteristic evaluation system. It is an exploded view of a hair surface characteristic sensor. It is explanatory drawing of the usage method of a hair surface characteristic sensor. It is a perspective view of a sliding part. It is a perspective view of a sliding part. It is a perspective view of a sliding part. FIG. 5 is a relationship diagram between a pressing pressure detected by a piezoelectric element and a resistance value detected by a pressing pressure sensor. It is a generation | occurrence | production test result of the stick-slip phenomenon in mildly damaged hair. It is a generation | occurrence | production test result of the stick slip phenomenon in a severely damaged hair. It is a frequency analysis figure of the result of having measured the hair end side by the color processing part, and the root side having not yet processed uncolored hair. It is a frequency analysis figure of the result of having measured the hair end side by the color processing part, and the root side having not yet processed uncolored hair. FIG. 9 is an integration diagram of signal strength in a specific frequency region in the frequency analysis diagram of FIG. 8. It is the schematic of the conventional comb-shaped sliding sound measuring apparatus. It is the measurement result of the sliding sound of the color processing part of the hair | bristle bundle measured by the conventional comb-shaped sliding sound measuring apparatus, and a non-color processing part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hair surface characteristic sensor 2 Sliding part 3 Piezoelectric element 4 Vibration absorber 5 Pressure sensor 6 Lead wire 7a, 7b Electrode 8a Film substrate 8b Substrate 9 Conductive plastic sheet 10 Spacer 11 Guide 20 Mounting tool 30 Detection means 40 Conventional Sliding sound measuring device 42 Sliding part 43 Microphone

Claims (13)

  A hair surface characteristic sensor that includes a sliding portion and a piezoelectric element that detects vibration of the sliding portion, causes the stick to slip by abutting the sliding portion against the hair and sliding the hair surface.   The hair surface characteristic sensor according to claim 1, wherein the sliding portion has a sliding surface having a surface tension of 25 mN / m or more.   The hair surface characteristic sensor according to claim 1 or 2, wherein the piezoelectric element has a sensitivity of -60 dB or more in the entire region of 50 to 3000 Hz when the maximum sensitivity output is 0 dB. Hair surface characteristics sensor according to claim 1, comprising a pushing pressure sensor can further detect the pressure of 20 to 200 g / cm ^2.   The hair surface property sensor according to any one of claims 1 to 4, further comprising an attachment device attached to a finger or a hand.   Hair surface characteristic sensor comprising a sliding part that slides on the hair surface and causes stick-slip and a piezoelectric element that detects vibration of the sliding part, and a sliding signal output by the piezoelectric element of the hair surface characteristic sensor Hair surface property evaluation system comprising detection means for detecting vibration caused by stick-slip.   The sliding part of the hair surface characteristic sensor has a sliding surface with a surface tension of 25 mN / m or more, and the piezoelectric element of the sensor is -60 dB or more in the entire region of 50 to 3000 Hz when the maximum sensitivity output is 0 dB. The hair surface property evaluation system according to claim 6, wherein the detection means detects periodic and strong vibrations against vibrations of healthy hair.   The hair surface property evaluation system according to claim 6 or 7, wherein the detection means calculates the integrated intensity of the sliding signal in an arbitrary range of 30 to 10000 Hz.   The surface of the hair is slid at the sliding part to cause stick slip, the vibration of the sliding part is detected by the piezoelectric element, the vibration of the stick slip is detected from the sliding signal output by the piezoelectric element, and the vibration of the stick slip is detected. Method for evaluating the surface properties of hair based on the above.   The evaluation method according to claim 9, wherein the sliding part is slid with the hair while the hair is sandwiched between the sliding part and the finger. The evaluation method according to claim 9 or 10, wherein a sliding portion having a sliding surface with a surface tension of 25 mN / m or more is used and sliding is performed by applying a pressure of ²⁰ to 200 cm / cm2.   The evaluation method according to claim 9, wherein the sliding speed is 0.5 to 10 cm / sec.   The evaluation method according to any one of claims 9 to 12, wherein the vibration of the sliding portion is detected by a piezoelectric element having a sensitivity of -60 dB or more in the entire region of 50 to 3000 Hz when the maximum sensitivity output is 0 dB.