WO2025158722A1 - Hair iron - Google Patents

Abstract

[Problem] The purpose of the present invention is to provide a hair iron capable of reducing damage to hair. [Solution] The hair iron according to the present invention comprises: a first arm and a second arm openably/closably connected; a first holding surface provided inside the first arm; a second holding surface provided inside the second arm; and a heating unit for heating hair provided on the first and second holding surfaces. The heating unit has a layer made of at least platinum.

Description

hair iron

The present invention relates to a hair iron, and in particular to a hair iron that can reduce hair damage.

Hair irons are commonly used for styling hair, including straightening, blow-drying, and treatments. These hair irons have a pair of arms connected to one end so that they can rotate, and a heating element is provided facing the other end of each arm. With the hair held between the heated heating elements, the hair iron can be slid toward the ends of the hair to heat the entire hair and style it.

For example, a hair styling device (1) including a handheld treatment unit (2) as a hair iron, the handheld treatment unit (2) having two arms (3, 4) configured to form a clamp with two surfaces (5, 6) facing each other and allowing a hair strand to be clamped, the handheld treatment unit including a steam diffusing means (7) configured to diffuse steam from a first surface (5) of the two surfaces to a second surface (6) of the two surfaces, is known (Patent Document 1).

Special table 2017-515590 publication

However, in conventional technologies, including the one described in Patent Document 1, the arm thickness is sometimes set thick to increase the heat capacity, which poses the problem of increasing the overall size and weight.

Furthermore, before using a hair iron, various chemicals such as oxidizing agents and reducing agents may be used, including hair color, hair treatment, and bleaching.

In such cases, after the oxidizing or reducing agent has achieved its intended purpose, it may end up damaging the hair instead. Attempts have been made to reduce hair damage by using agents that cause as little damage as possible to the hair or by avoiding prolonged use, but this has not always been sufficient.

For example, hydrogen peroxide, which is used in bleach, can provide good coloring, but it also acts on keratin, the main component of hair, breaking it down and causing damage to the hair, which is a problem.

Furthermore, many of the prior art techniques are designed to straighten curly hair, and do not take into consideration the possibility of creating permanent waves by curling the hair. Furthermore, if the arms are in good contact with each other when creating the curls described above, the process can be carried out more appropriately.

The object of the present invention is to provide a hair iron that can improve the adhesion between the arms.

In order to achieve the above objective, the inventors conducted extensive research into hair irons, and as a result, came up with the present invention.

That is, the hair iron of the present invention comprises a first arm and a second arm connected to each other so as to be able to open and close;
a first clamping surface provided on an inner side of the first arm;
a second clamping surface provided on the inner side of the second arm;
A hair iron having a heating section for heating hair, the heating section being provided on the first and second clamping surfaces, characterized in that the heating section has at least a layer made of platinum.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the heating section further has a layer made of at least one of nickel, copper, electroless nickel, and aluminum.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the thickness of the platinum layer is 0.05 to 1.0 μm.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the surface of the heating section is buff-polished.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the first and/or second arm is equipped with a hydrogen peroxide reduction device.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the first and/or second arms are further characterized by being equipped with a temperature control device.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the hydrogen peroxide reducer is characterized by reducing hydrogen peroxide by temperature setting.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the temperature is 80°C or higher.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the temperature is between 140°C and 180°C.

In addition, in a preferred embodiment of the hair iron of the present invention, it is further characterized by having a connecting member connecting the first arm and the second arm.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the hydrogen peroxide reduction device and the temperature control device are integrated into one unit.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the first and/or second arms are equipped with switches for the hydrogen peroxide reduction device and the temperature control device.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the connecting member is one or more.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the first and/or second arms are characterized by having a biasing portion that biases the clamping surfaces and elastically adjusts the clamping state between the clamping surfaces.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the first and/or second arms are characterized by having a core material installed along the longitudinal direction.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the core material has a stopper portion that engages with the clamping surface to restrict movement in the protruding direction relative to the first and/or second arms.

Furthermore, in a preferred embodiment of the hair iron of the present invention, at least one of the edges of the heating section in the hair insertion direction has a curl-forming curved surface that is curved in the thickness direction of the heating section.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the first arm and/or the second arm have a curved surface on the distal end edge in the hair insertion direction.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the iron is further characterized by having the curl-forming curved surface and/or a flat surface continuous with the curved surface.

The hair iron of the present invention has the advantageous effect of being able to provide a hair iron that can improve the adhesion between the arms. Furthermore, another aspect of the hair iron of the present invention has the advantageous effect of being able to reduce damage to hair.

Furthermore, with the hair iron of the present invention, when the gripping portion at the middle of the clamping arm is grasped and operated, the base ends rotate relative to each other and the tip ends perform a clamping action. This clamping action advantageously produces the effect of clamping and straightening the hair using the clamping surface (also called the straightener) located opposite the tip end of the clamping arm.

Furthermore, the hair iron of the present invention has the advantageous effect of allowing the hair to be sufficiently in contact with the curl-forming surface when setting the curl, thereby allowing for sufficient curl setting.

1 is a diagram showing the effect of a hair iron in one embodiment of the present invention. Although it is difficult to see in the figure, the bar graphs are displayed in the order of the ends, middle, and roots from the left. FIG. 2 is a diagram showing a hair iron according to one embodiment of the present invention. FIG. 3 is a top view of a hair iron according to an embodiment of the present invention. FIG. 4 is a diagram showing the hair iron of one embodiment of the present invention in a reversed state (rear side before assembly) of FIG. 5. FIG. 5 is a bottom view of a hair iron according to an embodiment of the present invention. FIG. 6 is a diagram showing the hair iron in one embodiment of the present invention in a reversed state (rear side before assembly) of FIG. 3. FIG. 7 shows a hair iron according to one embodiment of the present invention. 8 is a perspective view of the upper case portion of the main body for assembling the upper and lower parts of a hair iron according to an embodiment of the present invention. The plate and core material constituting the heating unit are conceptually illustrated. 9 is a side view of the upper case portion of the main body for assembling the upper and lower parts of a hair iron according to an embodiment of the present invention. The plate and core material constituting the heating unit are conceptually illustrated. 10 is a perspective view of the lower case of the main body for assembling the upper and lower parts of a hair iron according to an embodiment of the present invention. The plates and core material constituting the heating unit are conceptually illustrated. 11 is a side view of the lower case portion of the main body for assembling the upper and lower parts of a hair iron according to an embodiment of the present invention. The plate and core material constituting the heating unit are conceptually illustrated. Fig. 12 shows a schematic diagram of a configuration from a heating unit to a biasing unit in a hair iron according to one embodiment of the present invention. Fig. 12(a) shows a perspective view of a plate, Fig. 12(b) shows the plate and components therein, Fig. 12(c) shows a cross-sectional view of the plate and components therein, and Fig. 12(d) shows an example of the configuration of the components therein.

The hair iron of the present invention includes a first arm and a second arm connected to each other so as to be able to open and close;
a first clamping surface provided on an inner side of the first arm;
a second clamping surface provided on the inner side of the second arm;
A hair iron having a heating unit for heating hair provided on the first and second clamping surfaces, characterized in that the heating unit has a layer made of at least platinum. In the present invention, the first arm and the second arm are not particularly limited as long as they are connected in an openable and closable manner. In the present invention, hair can be clamped using a first clamping surface provided on the inside of the first arm and a second clamping surface provided on the inside of the second arm. The heating units for heating hair provided on the first and second clamping surfaces allow hair to be treated via both clamping surfaces.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the heating unit further comprises a layer made of at least one of nickel, copper, electroless nickel, and aluminum, from the viewpoint of improving adhesion with platinum. In the heating unit, the platinum on the outermost surface can come into direct contact with hair. With regard to the order of the layers, aluminum and platinum may result in insufficient adhesion, and by sandwiching nickel, copper, and nickel between the layers, adhesion can be improved. Furthermore, combinations of aluminum and copper, and platinum and copper may also result in insufficient adhesion, and when all materials are used, the order is preferably platinum, nickel, copper, electroless nickel, and aluminum.

As shown in Figure 12, which will be described later, strictly speaking, the heating unit can be configured as a plate, with a heating source such as a ceramic heater on the layer below the plate. These heating units (plates), as will be described later, can be shaped, for example, as shown in Figure 12.

Furthermore, in a preferred embodiment of the hair iron of the present invention, from the standpoint of reducing costs and improving adhesion, the thickness of the platinum layer is 0.05 to 1.0 μm. In other words, if the thickness is outside this range, there is a risk that the corners will become raised and the adhesion between the plates will be poor.

In a preferred embodiment, the thickness of the nickel layer is preferably 1 to 20 μm, more preferably 5 to 10 μm. In a preferred embodiment, the thickness of the copper layer is preferably 1 to 10 μm, more preferably 2 to 5 μm. In a preferred embodiment, the thickness of the electroless nickel layer is preferably 1 to 10 μm, more preferably 3 to 5 μm. In a preferred embodiment, the thickness of the aluminum layer is preferably 0.1 to 10 μm, more preferably 1 to 3 μm.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the surface of the heating unit is buff-polished. For example, by buff-polishing the surface of the aluminum plate that constitutes the heating unit to make it smoother, it is possible to eliminate unevenness in the layer placed on top of it, such as the platinum layer. Furthermore, buff-polishing in this manner makes it possible to improve adhesion when plates plated with platinum layers are joined together. Note that burrs may also be removed from the four corners of the plates.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the first and/or second arms are equipped with a hydrogen peroxide reducer. This makes it possible to efficiently remove excess hydrogen peroxide, for example, hydrogen peroxide used in bleach, and ultimately minimize damage to hair. The hydrogen peroxide reducer only needs to be installed on the arm, and there are no particular restrictions on its location. In a preferred embodiment, it can be installed anywhere from the center of the arm to the handle side of the arm, from the perspective of avoiding the clamping surface, which is expected to become hot due to the heating unit.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the hydrogen peroxide reducer reduces hydrogen peroxide by setting the temperature. In a preferred embodiment of the hair iron of the present invention, the temperature is 80°C or higher from the viewpoint of starting to reduce hydrogen peroxide. Furthermore, in a preferred embodiment of the hair iron of the present invention, the temperature is 140°C to 180°C from the viewpoint of more efficiently reducing hydrogen peroxide.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the first and/or second arms are further characterized by being equipped with a temperature control device. The temperature setting device only needs to be installed on the arm, and there are no particular restrictions on its location. In a preferred embodiment, it can be installed anywhere from the center of the arm to the handle side of the arm, from the standpoint of avoiding the clamping surface that is expected to become hot due to the heating unit.

Some hair irons have a temperature control device located midway along the power cord that comes out of the main body of the device, but in this case, it is necessary to manually operate the cord to turn the power on and off. In contrast, in the present invention, the hydrogen peroxide reduction device and temperature control device are located inside the arm, and as will be described later, if the switch function is located inside the arm, it is possible to turn the power on and off while holding the hair iron in the right hand. Furthermore, if the adjustment mechanism is in the form of a dial, the hydrogen peroxide and temperature can be easily adjusted by turning the dial with your thumb, improving operability.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the hair iron further comprises a connecting member connecting the first arm and the second arm. The connecting member connecting the two arms serves to suppress wobble at the tip of the iron (i.e., wobble from side to side when viewed from the tip of the iron). Specifically, it makes it possible to ensure that the plate surfaces align without misalignment when pressing the iron. Furthermore, in a preferred embodiment of the hair iron of the present invention, the connecting member is one or more, from the standpoint of operability.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the hydrogen peroxide reducer and temperature control device are integrated from the standpoint of operability. Further, in a preferred embodiment of the hair iron of the present invention, the first and/or second arms are equipped with switches for the hydrogen peroxide reducer and temperature control device. As mentioned above, the temperature control device may be installed in the middle of the power cord extending from the hair iron body, in which case it is necessary to operate the cord manually to turn the power on and off. On the other hand, in the present invention, the hydrogen peroxide reducer and temperature control device are installed inside the arm, and a switch may also be provided, thereby improving operability.

You can also bleach your hair before using a hair iron. Bleaching involves softening the hair using an alkaline agent. The main ingredients of bleach are hydrogen peroxide and ammonia water (an alkaline substance). The ammonia water acts on the cuticle on the surface of the hair, causing it to swell and soften. Hydrogen peroxide penetrates into the swollen and softened hair, where it chemically reacts with melanin. When black hair is bleached, the color changes from reddish-brown to reddish orange to yellowish orange to yellow, depending on the application time. This is mainly because the dark-brown "eumelanin" breaks down, while the orange-red "pheomelanin" is less likely to break down.

However, hydrogen peroxide does more than oxidize melanin. It can also decompose keratin, the main component of hair, potentially damaging the hair.

In the present invention, it is possible to minimize hair damage by quickly removing the hydrogen peroxide.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the first and/or second arms are characterized by having a biasing portion that biases the clamping surfaces and elastically adjusts the clamping state between the clamping surfaces. When the gripping portion at the middle of the first and/or second arms is grasped and operated, the base ends of the first and/or second arms rotate relative to each other, and the tip ends of the first and/or second arms (also referred to as first and/or second clamping arms) can perform a clamping action. This clamping action allows the clamping surfaces (clamping surfaces) arranged opposite the tip ends of the arms to clamp and straighten the hair.

Furthermore, the clamping arm can be movably supported so that at least one of the clamping surfaces can move toward and away from the other side, and the clamping arm can be provided with a biasing part that biases the clamping surfaces and elastically adjusts the clamping state between the clamping surfaces. This allows the clamping surfaces to securely clamp the hair. The biasing part is not particularly limited, and can be, for example, a spring, leaf spring, spring, rubber, etc. The biasing part, for example, a spring, etc., can be separated from the magnet-pressing leaf spring to strengthen the holding force. This makes it possible to sense the transfer of temperature more accurately.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the first and/or second arms are characterized by having a core material installed along the longitudinal direction.

A core material is installed inside the arm so that it runs longitudinally from the tip end to at least the gripping portion. This core material maintains its hardness up to a temperature higher than that of the clamping arm, preventing the tip end of the clamping arm from easily deforming due to heat when the heating portion of the clamping surface generates heat. Therefore, by gripping the gripping portion of the clamping arm, force can be smoothly transmitted from the tip end of the clamping arm to the clamping surface, allowing hair to be securely clamped and straightened.

As a result, even if the clamping arms are made thin and have a small heat capacity, they can still clamp and straighten hair reliably, and by making the overall hair lighter, it becomes easier to grip the clamping arms and work freely to straighten even the most curly hair for a certain period of time.

Furthermore, a receiving portion can be partially provided on the core material opposite the back of the urging portion and capable of supporting the urging portion. This allows the clamping reaction force from the clamping surfaces to be received by the receiving portion via the urging portion, allowing the clamping surfaces to more reliably clamp and straighten the hair.

Furthermore, because the receiving portion can be provided partially, its shape is less affected by the curved shape of the clamping arm, and the receiving portion can be easily positioned behind the biasing portion.

Furthermore, in a preferred embodiment of the hair iron of the present invention, the core member is characterized by having a stopper portion that engages with the clamping surface to restrict movement in the protruding direction relative to the first and/or second arm. In other words, movement of the clamping surface in the protruding direction relative to the clamping arm can be restricted by engaging with the stopper portion. Therefore, rattling of the clamping surface relative to the clamping arm can be restricted, allowing for more accurate clamping and straightening of hair between the clamping surfaces.

In a preferred embodiment, the clamping arm can be made separable. That is, the arm can have a mating structure in which the divided parts are joined together with fasteners, and the core material can be pre-attached to one of the divided parts with a temporary fastening portion provided at one longitudinal end. Therefore, when joining the divided parts together with the fasteners, there is no need to handle the core material individually; the divided parts can be fastened together and predetermined locations of the core material can be joined to the clamping arm by co-tightening with the co-tightening portion. Therefore, there is no need to handle the core material individually when joining the divided parts, and assembly of the clamping arm can also be facilitated.

Furthermore, in a preferred embodiment of the hair iron of the present invention, from the perspective of setting curls, at least one of the edges of the heating unit in the hair insertion direction has a curl-forming curved surface that curves in the thickness direction of the heating unit. The clamping surface has heating units that face each other, and at least one of the edges of the heating unit in the hair insertion direction can be provided with a curl-forming curved surface that curves in the thickness direction of the heating unit. It is also possible to provide at least one of the edges of the clamping arm in the hair insertion direction on the tip side with a curved and/or flat winding surface around which the hair is wrapped.

It is also possible for the hair wrapped around the curved curl-forming surface to extend linearly from the curved curl-forming surface and come into contact with the curved or flat surface of the winding surface. This allows the hair to come into full contact with the curved curl-forming surface when setting the curl, allowing for more thorough curl setting.

Furthermore, tension is applied to the hair by wrapping it around the clamping arm, and when the hair is pressed against the curl-forming surface, it can be easily slid across the curved or flat winding surface on the clamping arm side. Therefore, the tension applied to the hair by wrapping it can be effectively used to press the hair against the curl-forming surface, allowing for more thorough curl formation.

Furthermore, in a preferred embodiment of the hair iron of the present invention, from the viewpoint of setting a variety of curls, the first arm and/or the second arm are characterized by having a curved surface on the distal end edge in the hair insertion direction.

In the present invention, the clamping surface is equipped with a heating section having opposing straightening surfaces, and both edges of the heating section in the hair insertion direction can be provided with curl-forming curved surfaces that are curved in the thickness direction of the heating section.In addition, both edges of the clamping arm tip in the hair insertion direction can be provided with curved or flat winding surfaces around which the hair is to be wrapped.

This changes the degree to which the hair wraps around the two curl-forming surfaces, making it easy to create a variety of curls.

Furthermore, in a preferred embodiment of the hair iron of the present invention, from the viewpoint of being able to accurately clamp and straighten hair and accurately set curls, the iron is further characterized by having the curl-forming curved surface and/or a flat surface continuous with the curved surface.

In this invention, at least one of the clamping surfaces is supported on the clamping arm so that it can move forward and backward relative to the other side, and the clamping arm can be provided with a biasing section that biases the clamping surfaces forward and backward, elastically adjusting the clamping state between the clamping surfaces. Furthermore, because the hair wrapped around the curl-forming curved surface when the clamping surfaces are retracted has a flat surface that is continuous with the curl-forming curved surface and/or the curved surface, i.e., extends linearly from the curl-forming curved surface and comes into contact with the curved or flat surface of the wrapping surface, the hair can be accurately clamped and straightened by the opposing, retractable clamping surfaces, and the curl can also be accurately set.

In addition, in the present invention, the winding surface has a plane perpendicular to the clamping surface (straightening surface), and the plane of the winding surface and the curved curl-forming surface are close to each other in terms of their protruding positions in the hair insertion direction. Therefore, the tension imparted to the hair by winding can be used to straighten the hair by sliding it along the plane of the winding surface, as a pressing force against the curved curl-forming surface, making it possible to set a curl more reliably and easily.

In addition, in this invention, it is possible to improve or modify the plate, arm, cord, temperature control, magnet, etc. For example, the plate plating thickness can be modified to improve versatility when styling hair. A stopper to prevent lateral movement of the arm may also be provided to prevent lateral movement. The AC cord may also be provided to prevent breakage. Furthermore, painting (3 layers) is possible to prevent peeling, chemical resistance, and color coordination. Furthermore, a magnet may be used in the structure between the biasing part and the plate to improve heat resistance and magnetic force compatibility.

Temperature control is also possible to shorten the time it takes to reach the set temperature. A reinforcing plate shape may also be used to increase strength.

In terms of mechanism, the upper and lower casings of the hair iron contain a platinum plate, heat-dissipating silicon, ceramic heater, mica plate, heat-resistant magnet, magnet clamp, and plate clamp, and for control purposes it can be equipped with a thermistor, bimetal thermal fuse, PCB unit, etc. Furthermore, magnetism, temperature, platinum components, etc. cause various effects on various molecules, including water molecules, and the combined differential effects can create a more effective situation.

Below, examples using the hair iron of the present invention are described, but the present invention should not be construed as being limited to the examples below.

Example 1
FIG. 2 shows a hair iron according to one embodiment of the present invention. In the figure, 1 denotes a first arm, 2 denotes a second arm, 3 denotes a first clamping surface, 4 denotes a second clamping surface, 5 denotes a hydrogen peroxide reducer, 6 denotes a temperature control device, 7 denotes a connecting member, 8 denotes a connecting member, and 9 denotes a switch. Ironing with this hair iron can be briefly described as follows: The power plug is inserted into an outlet, and the clamping surfaces (3, 4) are heated by a heater (heat source). The first and second arms clamp hair between the clamping surfaces (3, 4), and the heating unit heats the clamped hair along the treatment surface of the clamping surfaces (3, 4). In this example, the hydrogen peroxide reducer 5 is installed inside the arm, and a switch 9 is also installed inside the arm. Therefore, the power can be turned on and off while holding the hair iron in the right hand. In this example, the hydrogen peroxide reduction device 5 and the temperature control device 6 are integrated and have a dial-like adjustment function. Therefore, hydrogen peroxide and temperature can be easily adjusted by turning the dial with one's thumb, improving operability. Note that temperature adjustment for the hydrogen peroxide reduction device 5 and the temperature control device 6 is not limited to a dial-like adjustment, and can also be performed using a push button, lever, or the like, and is not particularly limited.

Furthermore, as a hair iron equipped with a "hydrogen peroxide removal" mode, it is also possible to set the dial position on the iron to a "hydrogen peroxide removal" mode and set the temperature to 150°C.

Figure 3 shows a top view of a hair iron in one embodiment of the present invention. In the figure, 33 indicates one surface of the tip sides 29, 31, 35 indicates one surface of the gripping portions 21, 23, 37 indicates the inclined surfaces of both sides 33, 35, and 39 indicates the other surface of the tip sides 29, 31.

Figure 4 shows the hair iron of one embodiment of the present invention in an inverted state (reverse side before assembly) of Figure 5.

Figure 5 shows a bottom view of a hair iron in one embodiment of the present invention. In the figure, 33 indicates one surface of the tip sides 29, 31, 35 indicates one surface of the gripping portions 21, 23, 37 indicates the inclined surfaces of both sides 33, 35, and 39 indicates the other surface of the tip sides 29, 31.

Figure 6 shows the hair iron in one embodiment of the present invention in an inverted state (reverse side before assembly) compared to Figure 3.

Figure 7 shows a hair iron according to one embodiment of the present invention. In the figure, 3 indicates the first clamping surface, 4 indicates the second clamping surface, 15 and 17 indicate the base end, 19 indicates the rotation axis, 21 and 23 indicate the gripping portion, 25 and 27 indicate the force point, and 29 and 31 indicate the tip end.

Figure 8 shows a perspective view of the upper case portion of the main body for assembling the upper and lower parts of a hair iron in one embodiment of the present invention. The plates and core material that make up the heating unit are conceptually illustrated. In the figure, 50 indicates the core material, and 51 indicates the plates and other components.

Figure 9 shows a side view of the upper case portion of the main body for assembling the upper and lower parts of a hair iron in one embodiment of the present invention. The plates and core material that make up the heating unit are conceptually illustrated. In the figure, 50 indicates the core material, and 51 indicates the plates and other components.

Figure 10 shows a perspective view of the lower case portion of the main body for assembling the upper and lower parts of a hair iron in one embodiment of the present invention. The plates and core material that make up the heating unit are conceptually illustrated. In the figure, 50 indicates the core material, and 51 indicates the plates and other components.

Figure 11 shows a side view of the lower case portion of the main body for assembling the upper and lower parts of a hair iron in one embodiment of the present invention. The plates and core material that make up the heating unit are conceptually illustrated. In the figure, 50 indicates the core material, and 51 indicates the plates and other components.

Figure 12 shows a schematic diagram of the configuration of a hair iron in one embodiment of the present invention, from the heating section to the biasing section. In the figure, 60 indicates the plate, 61 indicates the ceramic heater (heat source), 62 indicates the mica plate, 63 indicates the bimetal, 64 indicates the bimetal holder, 65 indicates the leaf spring for holding the magnet, 66 indicates the leaf spring for the plate (biasing section), and 67 indicates the magnet. Figure 12(a) shows an oblique view of the plate, Figure 12(b) shows the plate and the components within the plate, Figure 12(c) shows a cross-sectional view of the plate and the components within the plate, and Figure 12(d) shows an example of the configuration of the components within the plate. The plate is formed using an aluminum base as shown in Figure 12(a), and can be plated with, for example, electroless nickel, copper, nickel, and platinum in that order. As shown in Figure 12(b), the following components can be arranged within the plate: ceramic heater (heat source) 61, mica plate 62, bimetal 63, bimetal holder 64, magnet holder leaf spring 65, plate leaf spring (biasing portion) 66, and magnet 67, for example, as shown in Figure 12(d). As shown, the spring has been changed and the spring that holds the bimetal thermal fuse has been separated from the magnet holder leaf spring, making it possible to further improve holding force. This configuration also makes it possible to sense temperature transmission more accurately.

As shown in these figures, the hair iron comprises an iron body connected to a power cord. The power cord may also be equipped with a temperature control device, power plug, etc.

Next, we will explain an embodiment of a hair iron that has a biasing portion, core material, stopper portion, etc.

The iron body includes a pair of clamping arms and a pair of clamping surfaces 3, 4. The clamping arms are made of resin, such as polyester-based engineering plastic with a linear expansion coefficient of 8.8 x 10-5 cm/cm/°C, and the base ends 15, 17 can be rotatably connected to each other via a rotation shaft 19. Gripping portions 21, 23 are provided at the middle of each clamping arm. These gripping portions 21, 23 are formed relatively thick as shown in Figure 7 to make them easier to grip, and can be made approximately the same thickness as the base ends 15, 17.

The gripping portions 21, 23 are provided with force points 25, 27 formed as inclined surfaces at their tip ends. These force points 25, 27 are placed on the gripping portions 21, 23 by the thumb or index finger to apply force when the gripping portions 21, 23 are gripped. When viewed from the side in Figure 7, the force points 25, 27 are formed to be slightly larger than the gripping portions 21, 23 as a whole, making it easier for the thumb or index finger to rest against them.

As shown in Figure 7, the tip sides 29, 31 of the clamping arms are formed to be thinner than the gripping portions 21, 23 in the direction in which they meet. Furthermore, as shown in Figure 3, the tip sides 29, 31 are formed to be thinner than the gripping portions 21, 23, and are set to be offset to one side relative to the gripping portions 21, 23. Therefore, one surface 33 of the tip sides 29, 31 protrudes to one side beyond one surface 35 of the gripping portions 21, 23, and both surfaces 33, 35 are set to be continuous in a stepped manner by an inclined surface 37. The other surface 39 of the tip sides 29, 31 is formed to be offset to one side to match the one surface 33, and extends into the center of the gripping portions 21, 23.

Such clamping arms are hollow and may have separate sections extending from the center, forming a joint structure. These separate sections can be fastened together at the tip ends 29, 31, the gripping sections 21, 23, and the base ends 15, 17 using fastening devices such as screws. Although not shown, fastening holes may be formed through the tip ends 29, 31 of the separate sections.

Although not shown, multiple reinforcing ribs may be provided within the hollow gripping portions 21, 23. One of the clamping arms may be provided with a convex portion on the opposing side of the arms, and the other clamping arm may be provided with a concave portion into which the convex portion fits. The convex portion may abut against the bottom surface of the concave portion, thereby functioning as a stopper.

In this way, the clamping arms are configured so that the base ends 15, 17 are rotatably connected to each other, and the tip ends 29, 31 perform clamping operations when the intermediate gripping portions 21, 23 are operated.

In the following explanation, since the tip ends 29 and 31 of the clamping arms are symmetrical, only tip end 29 will be explained, and for the other tip end 31, please refer to the explanation for tip end 29.

The tip side 29 can have a flat vertical wall surface and a flat bottom wall surface that house the core material inside. The tip side 29 can also have a clamping surface support hole that movably supports the clamping surface 3 so that it can move forward and backward relative to the other side. The clamping surface support hole can movably support the clamping surface 3.

Therefore, the clamping surfaces 3 and 4 are positioned opposite the tip ends 29 and 31 of the clamping arms, and the clamping action of the clamping arms clamps and straightens the hair while heating it.

When viewed from the clamping surface side, the clamping surface 3 consists of, in order, a heating unit, a ceramic heater, a magnetic plate, a first spring, and a second spring. A storage unit is integrally provided behind the heating unit, and can store the ceramic heater, magnetic plate, and first spring. The first spring and second spring can also press the storage unit in the direction of the hair contact surface, thereby fixing the heating unit and arm.

The heating section is made of a lightweight, highly thermally conductive material such as aluminum, and is formed into a rectangular plate when viewed from the opposite side, with its surface coated with fluorine.

In addition, protrusions can be provided on the upper and lower walls of the storage section to restrict the heating section from protruding beyond a certain extent.

The ceramic heater is a rectangular plate that generates heat up to a maximum temperature of approximately 180°C, conducts heat to the heating element, and is electrically connected to the power cord.

The magnet plate is formed into a rectangular plate using a 15,000 gauss neodymium magnet or the like, and is positioned so that the south poles face each other on both clamping surfaces 3 and 4.

In this embodiment, one of the biasing parts is a first spring, which is formed from a leaf spring. It biases the magnet plate toward the rear surface of the heating part within the housing part, bringing the ceramic heater into close contact with the rear surface of the heating part and providing stable support for the magnet plate.

Another biasing portion is a second spring. The second spring is supported at the rear end of the storage portion and constitutes a biasing portion that biases the clamping surfaces 3, 4 and elastically adjusts the clamping state between the clamping surfaces 3, 4. In a separable configuration, the second spring is formed from a leaf spring, both ends of which are inclined, so that the end edges can engage with the protrusions on the separated portion in the left-right direction (longitudinal direction).

Furthermore, a core material is housed within the tip sides 29, 31. This core material is formed symmetrically, and only one side of the core material will be described; the other core material will be described with reference to the core material on that side and will not be described here.

The core material is installed inside the clamping arm so that it extends longitudinally from the tip end 29 to at least the gripping portion 21. However, it is also possible to install the core material inside the clamping arm from the tip end 29 to the entire base end 15.

The core material maintains its hardness at temperatures higher than the clamping arms, and is able to restrict thermal deformation of the clamping arms. Therefore, in this embodiment, the core material is made of stainless steel, a material with a smaller linear expansion coefficient than the resin material of the clamping arms. However, the core material can also be made of titanium, ceramic, super engineering plastics, etc., as long as it has a smaller linear expansion coefficient than the clamping arms.

The core material can be provided with integral co-fastening portions at both ends of the long plate-shaped base portion. These co-fastening portions can be fastened together when the divided portions are mated and fastened together. The co-fastening portions have holes for inserting screws, which serve as fastening devices, and the co-fastening portions also have holes. A temporary fastening portion can be provided at its end, continuous with the co-fastening portion. This temporary fastening portion is provided at one longitudinal end of the core material and is intended to be pre-attached to the divided portions. This temporary fastening portion has a positioning hole that fits into a positioning pin that protrudes toward the divided portions. The temporary fastening portion also has a hole for inserting screws, which serve as fastening devices for temporary fastening.

A vertical wall portion is provided along one side edge of the long plate-shaped base portion. The vertical wall portion also serves as a stopper portion for the clamping surface 3. The other vertical wall portion is provided along the other side edge of the base portion and the other side edges of the co-fastening portion and temporary fastening portion.

In an aspect in which the hair iron is separable, the vertical wall portion may further have first and second fastening wall portions protruding therefrom. The first and second fastening wall portions may be located near the center of the vertical wall portion having a U-shaped cross section. These first and second fastening wall portions are fastened and fixed to the divided portion of the arm. The first fastening wall portion is located between both ends of the second spring. In other words, the first fastening wall portion can constitute a receiving portion that faces the back of the second spring, which is the biasing portion, and can support the second spring.

Next, we will explain how to use the hair iron to straighten curly hair or fix artificial permanent waves. It goes without saying that it is also possible to create permanent waves using a hair iron.

When using the hair iron, the first agent, that is, a liquid made by adding a basic substance such as ammonia, monoethanolamine, or triethanolamine to an aqueous solution whose main ingredient is a mercapto compound (reducing agent) such as thioglycolic acid or cysteine, and adjusting the pH to 6-10, is applied to the hair. This application reduces the disulfide bonds of the cystine contained in the keratin protein in the hair, cleaving them into mercapto groups. The hair is then washed with water, dried with a hair dryer, etc., and straightened with hair iron 1 heated to 140-180°C.

Specifically, grip the gripping arms by the gripping parts 21 and 23, and apply force by placing your thumb and index finger on the force points 25 and 27 to clamp the hair between the heating parts of the clamping surfaces 3 and 4. Then, while maintaining this position, slide the gripping arms toward the ends of the hair. This heats and straightens the hair that is clamped between the heating parts heated by the ceramic heater.

At this time, the hair moves at a set speed between the magnetic plates with their south poles facing each other, generating reduction energy according to Fleming's right-hand rule. This energy is generated from the south pole of the magnetic plate, whose electrons rotate clockwise, and promotes the reduction action of the first liquid. It also works to close the cuticle, which forms the outer layer of the hair. When the cuticle is closed, it blocks ultraviolet rays from penetrating into the hair, preventing damage to the hair from ultraviolet rays.

In addition, the energy of this reduction causes the water clusters in the first liquid to become smaller. As these clusters become smaller, the first liquid is able to penetrate the hair more easily, further promoting the reduction action of the first liquid. As a result, the treatment time, which can potentially damage the hair, can be shortened, and hair damage can also be reduced.

Then, a second liquid consisting of an aqueous solution of an oxidizing agent such as sodium bromate or hydrogen peroxide is applied to the hair, which oxidizes the mercapto groups and creates new disulfide bonds in the hair, solidifying the straight hair state.

When clamping and straightening hair in this way, the heat from the ceramic heater is also conducted to the tip ends 29, 31 of the clamping arms, reducing the hardness of the tip ends 29, 31 of the clamping arms and making them more susceptible to deformation.

Therefore, without a core material, when the hair is clamped between the heating units, the reaction force applied to the tip ends 29, 31 of the clamping arms could easily cause the tip ends 29, 31 to deform, which could prevent the heating units from clamping the hair evenly. By providing a core material, however, this problem can be alleviated.

In other words, the core material is installed from the tip side 29, 31 to at least the gripping portions 21, 23, and the gripping portions 21, 23 maintain a temperature that is lower than the tip side 29, 31 and allows for manual gripping, allowing the core material to be firmly supported by the gripping portions 21, 23.

Furthermore, since the co-tightening portion of this firmly supported core material is positioned within the force points 25, 27 of the gripping portions 21, 23, force can be accurately transmitted from the force points 25, 27 to the core material.

By accurately transmitting force to this core material, the clamping surfaces 3 and 4 are supported by the core material, preventing easy deformation of the tip ends 29 and 31. As a result, the heating elements can be accurately aligned to clamp the hair, allowing the above treatment to be performed accurately.

In addition, in this embodiment, the clamping surfaces 3 and 4 are biased by the second spring portion, which serves as a biasing portion, and the clamping state between the clamping surfaces 3 and 4 is elastically adjusted, allowing the above treatment to be performed more accurately.

The movement of the clamping surfaces 3 and 4 in the protruding direction can be restricted by a vertical wall portion (installed on the core material) that acts as a stopper, preventing rattling of the clamping surfaces 3 and 4. This not only allows the clamping surfaces 3 and 4 to continue to move accurately forward and backward due to the biasing action of the second spring portion, but also ensures that the heating section maintains an accurate clamping state.

The second fastening wall portion, which serves as the receiving portion, faces the back of the second spring, which serves as the biasing portion, and can receive the second spring portion by abutting both ends, allowing the reaction force of the second spring portion to be applied accurately to the heating portion.

As a result, the clamping state between the clamping surfaces 3, 4 by the second spring can be maintained accurately regardless of the temperature rise of the tip sides 29, 31. Furthermore, because the first fastening wall portion serving as a receiving portion is partially provided on the core material, it can be formed without being affected by the shape of the clamping arm, even if it tapers from the gripping portions 21, 23 toward the tip sides 29, 31. The base portion of the core material can be disposed on the flat bottom wall surface of the tip sides 29, 31 (the flat portion corresponding to the base in the cross section of the approximately trapezoidal tip sides 29, 31), and can be positioned straight and effortlessly all the way to the gripping portions 21, 23.

Note that the present invention is not limited to the above embodiment. For example, one or both of the clamping surfaces 3, 4 may be fixed so that they cannot move relative to the tip sides 29, 31. The magnet plate and first spring may also be omitted. The vertical wall portion of the core material, the first fastening wall portion, etc. may also be omitted.

Next, we will explain an example of a hair iron that has a curling surface, a curved surface, and a flat surface that is continuous with the curved surface.

This configuration has the following advantages. Tension is applied to the hair by wrapping it around the clamping arm, and when the hair is pressed against the curved curl-forming surface, the hair can be easily slid along the curved surface of the clamping arm. Therefore, the tension applied to the hair by wrapping it can be effectively used to press the hair against the curved curl-forming surface, allowing for sufficient curl formation.

In another aspect, curl-forming curved surfaces are provided on both edges of the heat plate in the hair insertion direction, and these curved surfaces are provided on both edges of the clamping arm tip in the hair insertion direction, and one of the back surfaces of the heat plate is positioned opposite the curved surface on the clamping arm tip.This allows the degree to which the hair wraps around both curl-forming curved surfaces to be changed, making it easy to create a variety of curls.

In another aspect, at least one of the straighteners is supported on the clamping arm so that it can move forward and backward relative to the other side, and the clamping arm is provided with a biasing means that biases the straightener to elastically adjust the state in which it is clamped by the straighteners, and a flat surface that is continuous with the curved surface is provided on the tip side of the clamping arm, so that when the straightener is retracted, hair that has wrapped around the curl-forming curved surface extends linearly from the curl-forming curved surface and comes into contact with the curved surface or the flat surface.As a result, the hair can be accurately clamped and straightened by the straighteners that are arranged opposite and can move forward and backward, and the curl can also be accurately set.

In another aspect, the plane that is continuous with the curved surface is perpendicular to the straightening surface, and the plane and the curl-forming curved surface are closely spaced in the hair insertion direction. Therefore, the tension applied to the hair by wrapping it around the hair can be used to press the hair against the curl-forming curved surface by sliding it along the curved surface or plane, making it easier and more reliable to set a curl.

For other configurations, please refer to the explanation of the hair iron mentioned above. The following explanation will focus on the curved surface, etc. Also, although there are tip sides 29 and 31, both tip sides 29 and 31 have roughly symmetrical, rounded, trapezoidal cross sections, so for convenience, only tip side 29 will be used for the explanation.

A flat straightening surface is provided on the heating section of clamping surface 3. However, this straightening surface is not limited to being flat, and can be configured in various shapes such as a curved surface or an S-curve surface. A straightening surface similar to the straightening surface is also formed on clamping surface 4, and the two surfaces face each other.

The heating section has curl-forming curved surfaces on both edges in the hair insertion direction (edges from the front to the back of the page in Figure 7) that curve in the thickness direction of the heating section (the up and down direction in Figure 7). The curl-forming curved surfaces are formed across the entire thickness of the heating section and present a quarter-circle arc.

Both edges of the clamping arm tip 29 in the hair insertion direction are provided with curved or flat winding surfaces for wrapping the hair (the cross section of the tip 29 in a direction perpendicular to the longitudinal direction can be a rounded, approximately trapezoidal shape, with the upper and lower base portions of this rounded, approximately large shape on the heating unit side). In other words, the upper base portion of the rounded, approximately trapezoidal shape can be the curved winding surface for wrapping the hair, and the lower base portion can be the flat winding surface for wrapping the hair, or vice versa. Curl-forming curved surfaces can be formed at both ends of the heating unit (clamping surface 3), while winding surfaces can be formed at both ends of the clamping arm tip 29. The degree to which the hair wraps around the two curl-forming curved surfaces can be changed by changing the relationship between the curl-forming curved surface and the winding surface, making it easy to create a variety of curls. In other words, it is possible to utilize two surfaces with different curvatures: the curl-forming curved surface at the end of the heating section and the wrapping surface at the arm tip 29.

The winding surface has a curve that curves in the same direction as the curl-forming curved surface. The curved surface of the rounded, approximately trapezoidal lower base portion (the length of the lower base portion is longer than the length of the upper base portion) is formed by an arc with a larger radius than the curved surface of the upper base portion.

The winding surface of the rounded, approximately trapezoidal lower base portion similarly has a flat surface that continues from the curved surface of the lower base portion at the end edge of the clamping arm tip side 29 in the hair insertion direction. This flat surface is formed perpendicular to the straightening surface. The flat surface of the winding surface of the lower base portion and the curl-forming curved surface of the lower base portion are close in protruding position in the hair insertion direction. The winding surface of the lower base portion has a curved winding surface that continues from the flat surface on the opposite side from the straightening surface.

On the other hand, the winding surface of the rounded, approximately trapezoidal upper base portion has a winding guide surface that is a curved surface with an even larger radius of curvature that is continuous with the curved surface of the upper base portion of the edge of the clamping arm tip side 29 in the hair insertion direction (the cross section is approximately trapezoidal because it is composed of flat and curved surfaces, and the corners are curved).

The clamping surface 3 is supported so that it can move back and forth as described above, and is biased by the second spring, so that when the clamping surface 3 is retracted, hair wrapped around the curl-forming surface of either the upper or lower base portion extends linearly from both curl-forming surfaces and comes into contact with the curved surface of the corresponding winding surface. On the winding surface side, the hair that extends linearly can also be set to come into contact with a flat surface.

Furthermore, with the above configuration, at least one of the edges of the heating section in the hair insertion direction is provided with a curl-forming curved surface that curves in the thickness direction of the heating section, and at least one of the edges of the clamping arm tip side 29 in the hair insertion direction is provided with a winding surface with a curved or flat surface around which the hair is wound, so that the hair wound around the curl-forming curved surface extends linearly from the curl-forming curved surface and comes into contact with the curved or flat surface of the winding surface.

Furthermore, when the clamping surface 3 is retracted, the hair wrapped around the curl-forming curved surface of the lower base portion extends linearly from the curl-forming curved surface of the lower base portion and comes into contact with the curved or flat surface of the wrapping surface of the lower base portion.

Next, we will explain how to use the hair iron to straighten curly hair or fix artificial permanent waves.

When using the hair iron, the first agent, that is, a liquid made by adding a basic substance such as ammonia, monoethanolamine, or triethanolamine to an aqueous solution whose main ingredient is a mercapto compound (reducing agent) such as thioglycolic acid or cysteine, and adjusting the pH to 6-10, is applied to the hair. This application reduces the disulfide bonds of the cystine contained in the keratin protein in the hair, cleaving them into mercapto groups. The hair is then washed with water, dried with a hair dryer, etc., and straightened with a hair iron heated to 140-180°C.

Specifically, grip the gripping arms by the gripping parts 21 and 23, and apply force by placing your thumb and index finger on the force points 25 and 27 to clamp the hair between the heating parts of the clamping surfaces 3 and 4. Then, while maintaining this position, slide the gripping arms toward the ends of the hair. This heats and straightens the hair that is clamped between the heating parts heated by the ceramic heater.

At this time, the hair moves at a set speed between the magnetic plates with their south poles facing each other, generating reduction energy according to Fleming's right-hand rule. This energy is generated from the south pole of the magnetic plate, whose electrons rotate clockwise, and promotes the reduction action of the first liquid. It also works to close the cuticle, which forms the outer layer of the hair. When the cuticle is closed, it blocks ultraviolet rays from penetrating into the hair, preventing damage to the hair from ultraviolet rays.

In addition, the energy of this reduction causes the water clusters in the first liquid to become smaller. As these clusters become smaller, the first liquid is able to penetrate the hair more easily, further promoting the reduction action of the first liquid. As a result, the treatment time, which can potentially damage the hair, can be shortened, and hair damage can also be reduced.

Then, a second liquid consisting of an aqueous solution of an oxidizing agent such as sodium bromate or hydrogen peroxide is applied to the hair, which oxidizes the mercapto groups and creates new disulfide bonds in the hair, solidifying the straight hair state.

Next, we'll explain how to create permanent waves using a hair iron.

The clamping action of the clamping surfaces 3 and 4 to hold the hair is the same as described above. When applying a permanent wave, the hair is pressed against the curl-forming curved surface of the upper or lower base portion. Therefore, while the hair is held between the clamping surfaces 3 and 4, the iron body is rotated, and the hair is wrapped around the tip side 29 or 31.

As a result, for example, when hair is wrapped around one of the curl correction curved surfaces of the heating unit, the hair begins to wrap from the start point of the curl forming curved surface and continues to wrap along the curl forming curved surface until it reaches the end point of the curl forming curved surface.

The hair extends in a straight line from the end point of the curl-forming curved surface and contacts the flat side of the curved winding surface at a point. The hair that contacts the winding surface at that point is then wound onto the flat surface and then onto the winding curved surface. In other words, at the roughly trapezoidal, rounded bottom surface, the hair can be wound from the curl-forming curved surface → the curved surface of the winding surface → the flat portion → the winding curved surface.

As a result, when setting a curl, the hair comes into sufficient contact with the curved curl-forming surface, allowing for sufficient curl setting. Furthermore, tension is applied to the hair by wrapping it around the clamping arm, and when trying to press the hair against the curved curl-forming surface, the hair can easily slide over the curved and flat winding surface on the clamping arm side. Therefore, the tension applied to the hair by wrapping it can be effectively used to press the hair against the curved curl-forming surface, allowing for sufficient curl setting.

The flat surface of the bottom portion is perpendicular to the straightening surface, and this flat surface and the curl-forming curved surface are close in protruding position in the hair insertion direction. As a result, the tension applied to the hair by wrapping it can be used to press the hair against the curl-forming curved surface by allowing it to slide more smoothly along the flat surface of the winding surface, making it easier and more reliable to set a curl.

The force pressing the hair against the curl-forming surface can be generated by winding it onto the winding surface. Because the flat surface is long and the distance between the winding surface and the curl-forming surface is large, a relatively large pressing force can be applied to the hair against the curl-forming surface by rotating the clamping arm, making it easier and more reliable to set the curl.

Next, when hair is wrapped around the other curl-correcting curved surface of the heating unit (the curl-correcting curved surface at the top of the rounded, roughly trapezoidal shape), the hair begins to wrap around from the starting point of the other curl-forming curved surface and continues to wrap around to the midpoint of the other curl-forming curved surface.

The hair extends in a straight line from the midpoint of the other curl-forming curved surface and contacts the curved winding surface of the upper base portion at a point. The hair that contacts the curved winding surface of the upper base portion at this point is then sequentially wound onto the winding guide surface on the opposite side from the heating section.

Therefore, when curling using the curl-forming surface of the upper base portion, the hair comes into contact with the curl-forming surface of the upper base portion up to the midpoint of the curvature, allowing for looser curls than those created by the curl-forming surface of the lower base portion. In other words, by changing the degree to which the hair wraps around the curl-forming surfaces of the upper and lower base portions, it is easy to create a variety of different curls.

Furthermore, when tension is applied to the hair by wrapping it around the clamping arm and the hair is pressed against the curved curl-forming surface of the upper base portion, the hair can be easily slid over the curved winding surface of the upper base portion on the clamping arm side and the winding guide surface. Therefore, the tension applied to the hair by wrapping it can be effectively used to press the hair against the curved curl-forming surface of the upper base portion, ensuring reliable curl formation.

Furthermore, in this embodiment, the curl-forming curved surfaces of the upper and lower base portions of the heating unit do not protrude beyond the winding surfaces of the upper and lower base portions, which are the edges of the clamping arm in the hair insertion direction, so the heating unit can be prevented from coming into contact with the person being treated during treatment.

However, the heating section can also be configured to protrude beyond the winding surfaces of the upper and lower base portions, which are the edges of the clamping arm in the hair insertion direction. In this case, for example, the heating section is provided with a curl-forming curved surface that curves in the thickness direction of the heating section on one or both of its edges in the hair insertion direction (upper or lower base portion). This curl-forming curved surface protrudes beyond the edges of the clamping arm in the hair insertion direction. This curl-forming curved surface is formed across the entire thickness of the heating section and can, for example, be a 1/2 circular arc.

A curved or flat winding surface for winding hair can be provided on the edge of the clamping arm tip side 29 in the hair insertion direction, corresponding to the curl-forming curved surface of the upper or lower base portion.

The winding surface of the upper or lower base portion has a curved surface that curves in the same direction as the curl-forming curved surface. The winding surface of the upper or lower base portion has a flat surface that is continuous with the curved surface of the upper or lower base portion. This flat surface is set at an acute angle to the straightening surface. The winding surface of the upper or lower base portion has a winding curved surface that is continuous with the flat surface on the opposite side from the straightening surface.

When hair is wrapped around the curl-forming curved surface of the upper or lower base portion of the heating unit, the hair begins to wrap from the starting point of the curl-forming curved surface of the upper or lower base portion and continues to wrap around to a point on the other side of the curl-forming curved surface.

Hair extends linearly from the point on the curl-forming curved surface of the upper or lower base portion and contacts the winding surface at a point on the plane. Hair that contacts the winding surface at this point on the plane is then wound sequentially onto the plane that is continuous with the winding surface.

Therefore, when curling hair using the curl-forming curved surface of the upper or lower base portion, the hair can come into contact with the curl-forming curved surface of the upper or lower base portion over an arc greater than 1/4 of a circle, allowing for even steeper curls to be formed than with the curl-forming curved surface. Furthermore, by combining both of the curl-forming curved surfaces, it is possible to easily form a variety of different curls.

Furthermore, when tension is applied to the hair by wrapping it around the clamping arms and the hair is pressed against the curved curl-forming surface of the upper or lower base, the hair can be easily slid along the flat surface of the winding surface on the clamping arm side. Therefore, the tension applied to the hair by wrapping it can be effectively used to press the hair against the curved curl-forming surface, ensuring reliable curl formation.

Note that the present invention is not limited to the above embodiment. For example, one or both of the clamping surfaces 3, 4 may be fixed so that they cannot move relative to the tip sides 29, 31. The magnet plate, first spring, etc. may also be omitted.

Using such a hair iron, we investigated whether hydrogen peroxide could actually be removed.

<Decomposition temperature of hydrogen peroxide>
Approximately 1 g of 100% human white hair bundle (product number: BM-WA, manufactured by Bealux) was bleached, and the hair bundle with residual hydrogen peroxide inside was used for evaluation. The decomposition temperature of the hydrogen peroxide inside the hair was determined using the following method, and this temperature was designated as the "hydrogen peroxide removal mode."

<Measurement of hydrogen peroxide concentration at ironing temperature>
Bleach 1 of Formulation Example 1 and bleach 2 of Formulation Example 2 were mixed at a 1:1 ratio until homogeneous, applied to a hair swatch, and left to stand at room temperature for 30 minutes. The mixture was then rinsed with warm water, washed with our Oolong Shampoo (trade name: Nano Supplement Cleansing Shampoo OT), rinsed with warm water, and dried with a hair dryer. The hair swatch was then passed through the hair iron of the present invention three times at temperatures set to 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, and 180°C. Each hair swatch was then wetted with water, and hydrogen peroxide concentration test strips (Mitsubishi Gas Chemical Trading Co., Ltd.: hydrogen peroxide concentration test strips) were pressed against the ends, middle, and roots of the hair swatch for 5 seconds. Visual concentration measurements and color measurements using a spectrophotometer were then performed. Table 1 shows Formulation Example 1 (Bleach 1). Table 2 shows Formulation Example 2 (Bleach 2).

<Determining the hydrogen peroxide decomposition temperature in a hair iron>
The hydrogen peroxide concentration test paper was then visually inspected and the results are shown in Table 3.

The hydrogen peroxide concentration test paper was measured in the L*a*b* color space using a spectrophotometer (model number: CM-36dG, manufactured by Konica Minolta) and the results are shown in Table 4 and Figure 1. The hydrogen peroxide concentration test paper turns bluer when the hydrogen peroxide concentration is high. Therefore, when measured with a spectrophotometer, the lower the b* value, the higher the hydrogen peroxide concentration. Tables 3 and 4 show that a temperature of 150°C or higher is appropriate, as this significantly reduces the hydrogen peroxide concentration. Therefore, the "hydrogen peroxide removal" mode can be set to 150°C.

As a result, it was found that it was possible to efficiently reduce hydrogen peroxide while operating the hair iron, minimizing damage to hair.

Although the hair iron has been described as being asymmetrical when viewed from above, the shape can be changed depending on the application. For example, in the case of a straightening iron, it can be basically symmetrical.

1 First arm 2 Second arm 3 First clamping surface 4 Second clamping surface 5 Hydrogen peroxide reduction device 6 Temperature control device 7 Connecting member 8 Connecting member 9 Switch 15, 17 Base end side 19 Rotating shaft 21, 23 Grip portion 25, 27 Force point portion 29, 31 Tip side 33 One surface 35 of tip side 29, 31 One surface 37 of grip portion 21, 23 Both sides 33, 35 are inclined surfaces 39 Other surface 50 of tip side 29, 31 Core material 51 Plate etc. 60 Plate (heating portion)
61 Ceramic heater (heat source)
62 Mica plate 63 Bimetal 64 Bimetal holder 65 Magnet holder leaf spring 66 Plate leaf spring (biasing portion)
67 Magnet

Claims (19)

a first arm and a second arm connected to each other so as to be able to open and close;
a first clamping surface provided on an inner side of the first arm;
a second clamping surface provided on the inner side of the second arm;
A hair iron having a heating section for heating hair provided on the first and second clamping surfaces, characterized in that the heating section has a layer made of at least platinum. The hair iron of claim 1, characterized in that the heating section further has a layer made of at least one of nickel, copper, electroless nickel, and aluminum. The hair iron according to claim 1 or 2, characterized in that the thickness of the platinum layer is 0.05 to 1.0 μm. A hair iron as described in any one of claims 1 to 3, characterized in that the surface of the heating unit is buff-polished. The hair iron according to any one of claims 1 to 4, characterized in that the first and/or second arm is equipped with a hydrogen peroxide reduction device. The hair iron of any one of claims 1 to 5, further characterized in that the first and/or second arms are equipped with a temperature control device. The hair iron described in any one of claims 1 to 6, characterized in that the hydrogen peroxide reduction device reduces hydrogen peroxide by setting the temperature. The hair iron according to claim 7, characterized in that the temperature is 80°C or higher. The hair iron according to claim 7, characterized in that the temperature is between 140°C and 180°C. The hair iron according to any one of claims 1 to 9, further comprising a connecting member connecting the first arm and the second arm. The hair iron of claim 6, wherein the hydrogen peroxide reduction device and the temperature control device are integrated. The hair iron of claim 6, characterized in that the first and/or second arms are provided with switches for the hydrogen peroxide reduction device and the temperature control device. The hair iron according to claim 10, characterized in that the connecting member is one or more. A hair iron as described in any one of claims 1 to 13, characterized in that the first and/or second arm has a biasing portion that biases the clamping surfaces and elastically adjusts the clamping state between the clamping surfaces. A hair iron as described in any one of claims 1 to 14, characterized in that the first and/or second arms have a core material installed along the longitudinal direction. A hair iron as claimed in any one of claims 1 to 15, characterized in that the core material has a stopper portion that engages with the clamping surface to restrict movement in the protruding direction relative to the first and/or second arms. The hair iron according to any one of claims 1 to 16, characterized in that at least one of the edges of the heating section in the hair insertion direction has a curl-forming curved surface that curves in the thickness direction of the heating section. The hair iron according to any one of claims 1 to 17, characterized in that the first arm and/or the second arm have a curved surface at the end edge in the hair insertion direction on the tip side. The hair iron according to claim 17 or 18, further comprising a curved curl-forming surface and/or a flat surface continuous with the curved surface.