KR20070034514A - Ceramic heater, manufacturing method thereof, heating device and hair iron - Google Patents

Abstract

In the ceramic heater including a ceramic body having a conductor pattern embedded with an outer surface in order to provide a durable ceramic heater by preventing insulation degradation at a high temperature, the conductor pattern is provided such that a return portion of the resistance heating element is formed. It was set as the conductor and the void occupancy rate of the ceramic part inserted in the adjacent conductor in the return part was made into 0.01 to 50% of range.

Description

CERAMIC HEATER AND PRODUCTION METHOD THEREFOR AND HEATING DEVICE AND HAIR IRON

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heater for heating a sensor, in particular an automobile air-fuel ratio detection sensor for heating, a carburetor heater, a hair iron, a soldering iron, a ceramic heater, a heating device and a hair iron using the same.

Background Art Conventionally, aluminum oxide ceramic heaters formed by embedding heat generating resistors made of high melting point metals such as W, Re, and Mo in ceramics containing aluminum oxide as a main component have been widely used.

For example, when manufacturing a cylindrical ceramic heater, as shown in FIG. 10, the ceramic molded object 12 and the ceramic green sheet 13 are prepared, and W, Re is formed on one surface of the ceramic green sheet 13; After forming the heat generating resistor 14 and the lead lead-out part 15 which are made of a high melting point metal such as Mo, and the like, the electrode pads are formed on the back surface (the other side) (not shown), and then the heat generating resistor 14 and the lead are formed. The lead-out portion 15 is wound around the ceramic formed body 12 so as to be inward and baked. Moreover, the lead lead-out part 15 and the electrode pad are connected by the through-hole 16 formed in the ceramic green sheet 13 (for example, refer patent document 1).

The conventional ceramic heater is formed by simultaneously baking the paste-type heat generating resistor 14 with the ceramic molded body 12 and the ceramic green sheet 13. And the heat generating resistor of the ceramic heater produced in this way becomes a curved shape folded back several times (FIG. 1 of patent document 2).

Further, in Patent Documents 3 to 5, the bases of the pair of holding members are connected to the shaft so as to be opened and closed, and the front end portions of both holding members are opened to each other by pressing the springs provided in the bearing portion, and both holding members Hair irons each provided with a heater plate inside the opening portion of the tip portion of are disclosed.

The hair iron had a structure in which a nichrome wire was wound on a ceramic insulating plate and the heater plate, which was covered on both sides again with an insulating plate, was fitted into a plate-like body, or pressed by a plate spring to transfer heat from the heater plate to the plate-like body.

[Patent Document 1] Japanese Patent Application Laid-Open No. 2001-126852

[Patent Document 2] Japanese Patent Application Laid-Open No. 2001-102156

[Patent Document 3] Japanese Patent Application Laid-Open No. 2000-232911

[Patent Document 4] Japanese Patent Application Laid-Open No. 2002-291517

[Patent Document 5] Japanese Patent Application Laid-Open No. 2000-14438

In recent years, however, ceramic heaters have been used in higher temperature environments, whereby lowering durability has become a problem. In other words, when continuous energization is performed at high temperatures, insulation between adjacent patterns is deteriorated, durability is lowered, and eventually, a problem arises such as sparking or disconnection.

In addition, a heater produced by winding a heating element made of nichrome wire on an insulating plate is disconnected by repetition of heating or heating, or the heating element reacts with moisture in the air to form a reaction layer, thereby increasing the resistance value of the heating element, and thus, a predetermined voltage at a predetermined voltage. There is a concern that the temperature will not be reached, and there is a problem that durability is poor.

In addition, the heater plate made of nichrome wire has a problem that it is difficult to arrange the heating element on the heater plate uniformly, so that the heating surface of the plate-like body cannot be uniformly heated.

In addition, since the heating surface of the heater plate and the surface of the plate-like body are not evenly thermally contacted, it is difficult to transfer the heat of the heater plate to the plate-like body uniformly, and there is a problem that the temperature of the heating surface cannot be made uniform.

This invention is made | formed in view of the said situation, and makes it a 1st objective to provide the ceramic heater which is excellent in durability, preventing the fall of insulation at high temperature.

Another object of the present invention is to provide a heating device and a hair iron capable of uniformly heating the heating surface of the plate-like body.

In order to achieve the first object described above, the ceramic heater according to the present invention comprises a ceramic body having a conductor pattern embedded with an outer surface, the conductor pattern is made of a conductor provided to form a return portion of the resistance heating element, It is characterized by the void occupancy rate of the ceramic part inserted in the adjacent conductor in the said return part is 0.01 to 50%.

Here, the ceramic portion sandwiched between the adjacent conductors refers to a ceramic portion sandwiched between the conductors in a conductor forming region defined as an inner region along the outer surface with a thickness substantially the same as that of the conductor.

In addition, the first manufacturing method of the ceramic heater according to the present invention comprises the steps of forming a conductor paste in a predetermined pattern on the surface of the first ceramic green sheet;

A ceramic green sheet laminate is produced by laminating a second ceramic green sheet having a thickness at least the same as that of the conductor pattern on the surface on which the conductor paste of the first ceramic green sheet is formed and which is more flexible than the first ceramic green sheet. Process to do,

Bonding the ceramic green sheet laminate to a ceramic formed body;

And the step of firing the bonded ceramic green sheet laminate and the ceramic formed body.

Moreover, the 2nd manufacturing method of the ceramic heater which concerns on this invention is

Forming a conductor paste in a predetermined pattern on the surface of the ceramic green sheet;

Filling an insulator between the conductor pastes in the predetermined pattern;

Bonding a ceramic green sheet filled with an insulator between the conductor pastes to a ceramic molded body using a surface on which the conductor paste is formed as a bonding surface;

It is characterized by including the process of baking the said bonded ceramic green sheet and ceramic molding.

In addition, in order to achieve the second object, the heating apparatus according to the present invention comprises a heater plate made of a plate-shaped ceramic body embedded with a resistance heating element, having a thickness in the range of 0.5 ~ 5.0mm,

It has a 1st and 2nd surface, The said heating plate is provided in the 1st surface, The said 2nd surface is a heating surface, The heating surface is provided with the plate-shaped object which consists of a flat part and the chamfer part of the periphery. It features.

Hair iron according to the invention is characterized in that it is configured using a ceramic heater according to the invention or a heating device according to the invention.

Effect of the Invention

In the ceramic heater according to the present invention described above, since the void occupancy rate of the ceramic body between the conductors is 0.01 to 50%, it is possible to prevent insulation deterioration at a high temperature and provide a highly durable ceramic heater.

That is, the invention of the ceramic heater was completed by discovering that the insulation lowering at high temperature can be prevented as long as the void occupancy in the ceramic portion between the conductors is within a certain range.

In addition, since the heating device according to the present invention embeds a resistive heating element in a plate-shaped ceramic body, the resistive heating element is not exposed to steam or the like, which is excellent in durability and can be repeated rapid heating, and the temperature difference in the heating surface can be reduced. The heating material can be heated evenly.

In addition, the hair iron according to the present invention can provide a high durability of the hair iron by having a ceramic heater according to the present invention or a heating device according to the present invention.

In addition, in the hair iron according to the present invention, since the local heating portion is not generated on the heating surface by providing the heating device according to the present invention, for example, the hair iron is provided with no fear of damaging the hair by partially heating the hair. can do.

1 is a partially broken perspective view showing the configuration of a ceramic heater according to the first embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along line X-X in the ceramic heater of FIG. 1.

3 is an enlarged cross-sectional view of conductors in the cylindrical ceramic heater of the first embodiment.

4 is an enlarged cross-sectional view of conductors in a plate-shaped ceramic heater according to a modification of the first embodiment.

Fig. 5 is a partially notched side view showing the structure of the hair iron of the second embodiment according to the present invention.

FIG. 6 is a front view showing the positional relationship between a heater plate and a plate-like body used in the hair iron of FIG. 5.

FIG. 7 is a cross-sectional view taken along line X-X of FIG. 6.

8 is a sectional view of a heating apparatus of a modification of Embodiment 2 according to the present invention.

9 is a plan view of a heater plate used in the heating apparatus of the second embodiment.

10 is a developed view of a ceramic heater of the conventional example.

<Description of the symbols for the main parts of the drawings>

1: ceramic heater 2: ceramic heartwood

3: ceramic sheet 4: heat generating resistor

5: Lead out part 6: Through hole

7: Electrode pad 8: Lead member

A: Area between conductors in a cylindrical ceramic heater

B: Area between conductors in flat ceramic heater

5: heating device 50: holding member

52: shaft 53: coil spring

54: bearing part 55: plate-shaped body

55a: heating surface 57: heater plate

58: resistance heating element 59: spring

61: lead wire

EMBODIMENT OF THE INVENTION Hereinafter, embodiment which concerns on this invention is described, referring drawings.

Embodiment 1

1 is a partially broken perspective view of the ceramic heater 1 of Embodiment 1 according to the present invention, and FIG. 2 is a cross-sectional view taken along line X-X in FIG.

In the ceramic heater 1 of the first embodiment, the heat generating resistor 4 is incorporated in a ceramic body composed of the ceramic core material 2 and the ceramic sheet 3. Here, the heat generating resistor 4 is composed of a return portion in the conductor pattern, and the void occupancy rate of the ceramic body between the adjacent conductors in the portion where the heat generating resistor 4 is formed is 0.01 to 50%. will be.

The ceramic heater 1 heats the ceramic green sheet (the ceramic sheet 3 after firing), in which the heat generating resistor 4 and the lead lead portion 5 are formed on the surface, and the electrode pad 7 is formed on the rear surface thereof. The resistor 4 and the lead lead portion 5 are wound to a ceramic molded body (the ceramic core 2 after firing) so as to be inward, and is obtained by close firing. The lead lead portion 5 and the electrode pad 7 are connected by through holes 6 formed in the ceramic sheet 3.

The ceramic body is composed of a ceramic core material 2 from which a ceramic molded body is fired and a ceramic sheet 3 from which a ceramic green sheet is fired. The ceramic body is made of various ceramics such as aluminum oxide ceramics, silicon nitride ceramics, aluminum nitride ceramics, silicon carbide ceramics, and the like, and particularly, aluminum oxide or silicon nitride is preferably employed as a main component, and therefore, rapid heating and The ceramic heater 1 excellent in durability can be obtained. For example, in the case of aluminum oxide ceramics, Al ₂ O ₃ 88 to 95% by weight, SiO ₂ 2 to 7% by weight, CaO 0.5 to 3% by weight, MgO 0.5 to 3% by weight, ZrO ₂ 1 to 3% by weight It is preferable to use the composition. If the Al ₂ O ₃ content is less than 88% by weight, the glass quality increases, which may increase migration during energization. On the other hand, when the Al ₂ O ₃ content exceeds 95% by weight, the amount of glass diffused into the metal layer of the heat generating resistor 4 embedded in the ceramic heater 1 decreases, and the durability of the ceramic heater 1 may be deteriorated. have. In the case of silicon nitride ceramics, 3 to 12% by weight of rare earth element oxide, 0.5 to 3% by weight of Al ₂ O ₃ as the sintering aid, and 1.5 to 5% by weight of SiO ₂ contained in the sintered body with respect to silicon nitride as the main component It is preferable to mix SiO ₂ so that it may become%. The amount of SiO ₂ is shown here, and SiO ₂ produced from impurity oxygen contained in silicon nitride raw material, the sum of SiO ₂ and, SiO ₂ by intentionally added as an impurity to be contained in other additives. In addition, by dispersing MoSi ₂ or WSi ₂ in the silicon nitride of the base material, the durability of the heat generating resistor 4 can be improved by bringing the thermal expansion rate of the base material closer to that of the heat generating resistor 4.

In addition, the heat generating resistor 4 is constituted by a meandering conductor pattern, and the lead lead portion 5 formed to have a resistance value of about 1/10 is connected to the heat generating resistor 4. In order to simplify a normal work, they often print-form the heat generating resistor 4 and the lead lead-out part 5 simultaneously on the ceramic green sheet (it turns into the ceramic sheet 3 after baking). Moreover, the return part in this invention also includes the shape folded by the U-shape and meandering so that it may become a desired resistance value.

Here, about the dimension of the ceramic heater 1, outer diameter or width can be 2-20 mm and length can be about 40-200 mm, for example. As the ceramic heater 1 for heating an air-fuel ratio sensor of an automobile, it is preferable to make an outer diameter or width 2-4 mm, and length 50-65 mm. Moreover, it is preferable to make the heat generating length of the heat generating resistor 4 into 3-15 mm for the automotive use. If the heat generation length is shorter than 3 mm, the temperature rise at the time of energization can be increased, but the durability of the ceramic heater 1 is lowered. If the heat generation length is longer than 15 mm, the temperature increase rate becomes slow, and if the temperature increase rate increases, the power consumption of the ceramic heater 1 becomes large, which is not preferable. In addition, a heat generation length is the length of the longitudinal direction of the meandering heat generating resistor 4 shown in FIG. 1, and this heat generation length is suitably selected according to the intended use.

In addition, although the boundary line is drawn between the ceramic core material 2 and the ceramic sheet | seat 3 in FIG. 2, when the unbaked ceramic molded object and the ceramic green sheet are bonded together, it fires, and the boundary as this joining surface disappears. There are many.

In this Embodiment 1, it is preferable to form the primary plating layer after baking in the electrode pad 7 of the ceramic heater 1. This primary plating layer is for improving the flow of the solder material and increasing the soldering strength when soldering the lead member 8 to the surface of the electrode pad 7. The primary plating layer is preferable because the adhesion strength is increased by the thickness of 1 to 5 µm. As a material of a primary plating layer, Ni, Cr, or the composite material which has these as a main component is preferable, and the plating which has Ni as a main component excellent in heat resistance is more preferable.

In addition, when using in an atmosphere with high humidity, it is preferable to use the Au-based or Cu-based solder material because migration hardly occurs. As the solder material, those having Au, Cu, Au-Cu, Au-Ni, Ag, or Ag-Cu type are preferable because of their high heat resistance. Au-Cu solder, Au-Ni solder, and Cu solder are especially preferable because they have high durability. It is preferable to form the secondary plating layer which is usually made of Ni on the surface of the solder material in order to improve the high temperature durability and protect the solder material from corrosion.

In addition, as the material of the lead member 8, since the temperature of the lead member 8 rises during use by heat transfer from the heat generating resistor 4, it is preferable to use Ni-based or Fe-Ni-based alloys having good heat resistance. .

The part characterized by the present invention is a ceramic heater 1 having a conductor pattern embedded therein, the conductor pattern having a return portion constituting the heat generating resistor 4, and between any conductors adjacent to the return portion. The void occupancy rate of the ceramic body in this case is 0.01 to 50%. Moreover, the void occupancy rate of the ceramic body between arbitrary conductors adjacent in the return part is more preferably 0.1 to 40%, still more preferably 1 to 20%. If the void occupancy is less than 0.01%, the rapid heating and rapid lowering are repeated, so that the heat dissipation of the ceramic body around the heat generating resistor 4 is insufficient when the heat generating resistor 4, which is the heating part, is expanded. Thermal expansion of the heat generating resistor 4 does not depend on the thermal expansion of the heat generating resistor 4, and stress may concentrate on the edge portion 41 of the heat generating resistor, resulting in cracking or disconnection. On the other hand, when this void occupancy is larger than 50%, when continuous energization is performed at high temperature, the insulation of the ceramic body around the heat generating resistor 4 which is the heating portion tends to deteriorate and the durability performance tends to be lowered. Moreover, when the ceramic green sheet is adhered to the ceramic molded body as it is and adhered and fired, the numerical value is larger than the void occupancy in the above range. Therefore, in order to make the void rate of the said range, the manufacturing method mentioned later is employ | adopted.

FIG. 2: is sectional drawing (XX line sectional drawing shown in FIG. 1) which shows an example of the cross section perpendicular | vertical to a longitudinal direction, and the conductor in the return part (heat generating resistor 4) of a conductor pattern is the outer periphery of the ceramic core material 2 The state arrange | positioned circularly is shown. Here, the void occupancy rate of the ceramic body between the conductors is 0.01 to 50%, as shown in FIG. 3, the voids of the ceramic body between any adjacent conductor patterns (4a and 4b in FIG. 3) that are adjacent to each other. It means that the occupancy rate when measured is 0.01 to 50%. The portion where the void ratio of the ceramic body is 0.01 to 50% may be any portion of the cross section for cutting the heat generating resistor 4 perpendicular to the longitudinal direction. In addition, when a ceramic body is a cylindrical shape, as for a conductor, as shown in FIG. 3, the upper side of the adjacent conductor pattern 4a and the upper side of the conductor pattern 4b are the outer periphery circles of the ceramic core material 2 (in other words, A line connected along the outer surface of the ceramic body), a line connecting the lower side of the conductor 4a and the lower side of the conductor 4b along the outer circumference of the ceramic core 2, and the surfaces of the conductors 4a and 4b. In the case where the ceramic body is in a flat plate shape, as shown in FIG. 4, a line connecting the upper side of the adjacent conductor 4c and the upper side of the conductor 4d and the lower side of the conductor 4c are shown. The area | region B enclosed by the line which connected the lower side of the conductor 4d, and the surface of conductor 4c, 4d is said.

In the present specification, in the case where the ceramic body is cylindrical, the annular region and the ceramic body sandwiched by the outer circumference separated by the thickness of the conductor from the outer circumference along the outer circumference of the ceramic core material 2 and the outer circumference thereof are flat. An inner region sandwiched by a line connected to contact the upper side of each conductor and a line connected to the lower side of each conductor in is referred to as a conductor formation region. That is, between the conductors defined as described above means a portion located between adjacent conductors in the conductor formation region.

Moreover, in the ceramic heater of this Embodiment 1, it is preferable that the length along the outer surface of the void which exists between adjacent conductors is less than the length of 1/2 of the space | interval of conductors. That is, in the return portion of the conductor pattern, an arbitrary length of more than half of the length (distance between conductors) of the ceramic body between the conductors on any line connecting adjacent conductors along the outer surface. It is preferable that no void is present. When the length of the void exceeds 1/2 of the distance between the conductors, the insulation of the ceramic body surrounded by the heat generating resistor 4 as the heating portion deteriorates when continuous energization is performed at high temperature, thereby deteriorating durability. In addition, in the case of the cylindrical ceramic heater shown in FIG. 3, arbitrary lines are arbitrary which connects the adjacent conductor 4a and the conductor 4b in area | region A along an outer surface, for example. Says the line. The arbitrary line in this case becomes an arc-shaped curve which has a center substantially the same as the center of the circle which consists of the outline (outer surface of a ceramic body) of sectional drawing of the cylindrical ceramic heater shown in FIG. Moreover, in the case of the flat-shaped ceramic heater shown in FIG. 4, the arbitrary straight line which connects the adjacent conductor 4c and the conductor 4d in area | region B is said.

Moreover, in this invention, it is preferable that the thickness of the conductor which comprises a conductor pattern, especially the heat generating resistor 4 is 5-100 micrometers. If the thickness of the conductor pattern is less than 5 µm, voids between any of the above-mentioned conductors can be prevented, but in the high temperature continuous endurance test and the high temperature cycle endurance test, the resistance change and disconnection of the heating resistor 4, which is the heating part, may occur, resulting in durability Deteriorates. On the other hand, when the thickness of a conductor pattern exceeds 100 micrometers, it exists in the tendency for it to become difficult to restrain the void rate between adjacent arbitrary conductors to 50% or less.

Next, the method for making the void occupancy ratio of the ceramic body between adjacent conductors 0.01 to 50% is described.

As an example, a conductor pattern is formed on the surface of the first ceramic green sheet, and at least on the conductor pattern formation surface side of the first ceramic green sheet, the thickness is substantially the same as the thickness of the conductor pattern, preferably the same thickness and the first ceramic. A method of laminating a second ceramic green sheet that is more flexible than the green sheet can be adopted. According to this method, voids between patterns can be eliminated by filling the voids for the thickness of the conductor pattern with the second flexible ceramic green sheet. Here, the second ceramic green sheet needs to be more flexible than the first ceramic green sheet. When the second ceramic green sheet is flexible, the second ceramic green sheet is applied to the first ceramic green sheet subjected to the conductor pattern. This is because both ceramic green sheets are in close contact with each other at least in the center between conductors when they are joined. Here, it is preferable that the hardness of this ceramic green sheet is measured by a digital indicator (made by Mitsutoyo), and the depth at which the needle of φ1 mm penetrates for 30 seconds is 200 µm or more. This is because when the hardness of the ceramic green sheet, that is, the penetration depth is less than 200 µm, voids are formed because there is no contact between the conductors without gaps. Moreover, in order to reduce the space | gap between patterns, you may apply pressure using a press etc.

As another method, a method of screen printing a paste can also be adopted. This method is performed as follows. First, the heat generating resistor 4 and the lead lead-out portion 5 are screen printed on the ceramic green sheet. At this time, the paste applied by screen printing is an organic resin binder composed mainly of a powder and an adhesive component mainly composed of a high melting point metal (W, Mo, Re, etc.), an organic solvent mainly used as ethyl cellulose, nitrocellulose and a diluent, mainly TPO. (Terpineol), DBP (dibutyl phthalate), DOP (dioctyl phthalate), BCA (butyl carbitol acetate), etc., are mixed. These pastes are printed in the range of 5-150 micrometers of raw thickness. Further, the conductor pattern is formed by adjusting the line width, the printing thickness, or the resistivity of the paste so that the resistance value of the heat generating resistor 4 becomes about 10 times the resistance value of the lead lead-out portion 5. Next, a paste containing an insulator is screen printed in order to fill gaps in thicknesses between adjacent conductors. The paste used at this time is an insulating material having a high melting point, mainly the same composition as the ceramic green sheet, that is, 88 to 95% by weight of Al ₂ O ₃ , 2 to 7% by weight of SiO ₂ , 0.5 to 3% by weight of CaO, 0.5 to MgO 0.5 to Organic resin binder composed of an adhesive component to aluminum oxide ceramics composed of 3% by weight and 1 to 3% by weight of ZrO ₂ , an organic solvent mainly used as ethyl cellulose, nitrocellulose and a diluent, mainly TPO (terpineol), DBP (di Butyl phthalate), DOP (dioctyl phthalate), BCA (butyl carbitol acetate) and the like. As the paste, in addition to the ceramic green sheet composition, an aluminum oxide single component or an insulating material having a volume resistivity of 10 ⁸ Ω or more can be used. It is preferable to adjust and print the viscosity of a paste in the range of 50 dPa * s-1000 dPa * s here. When the viscosity of the paste is 50 dPa · s or less, the printability is excellent, but the raw density is low. Therefore, the amount of dry shrinkage increases, so that a step occurs in the upper portion of the conductor pattern, and voids tend to occur after firing. Moreover, at the viscosity of 1000 dPa * s or more, since leveling property falls, since a void etc. tend to arise in a film, it is unpreferable. In addition, screen printing is performed by the screen which inverted the heat generating resistor and the lead lead-out part.

As another method, a filling method using a dispenser can also be employed. As described above, if the paste viscosity is 1000 dPa · s or more, the present density can be set high, and the amount of shrinkage due to dry shrinkage can be made infinitely small, so that the voids between the conductors can be reliably filled. It is not preferable and cannot be adopted. Therefore, when using such a high viscosity paste, the filling method using a dispenser can be preferably used.

This method of screen printing or using a dispenser is effective in that an insulator can be filled between conductors rather than on a conductor pattern.

In addition, although the embodiment of the present invention discloses a ceramic body in which a ceramic green sheet is wound around a cylindrical ceramic molded body and fired, the present invention provides a plate-shaped ceramic molded body or printing of a conductor or the like on a ceramic green sheet. It also includes a ceramic body formed by joining and firing a ceramic green sheet.

Embodiment 2

Next, the heating apparatus 51 of Embodiment 2 which concerns on this invention is demonstrated.

FIG. 5 is a partially cutaway side view showing an example of the configuration of the hair iron 100 using the heating device 51 of the second embodiment. In FIG. 5, reference numeral 50 denotes a gripping member, reference numeral 52 denotes an axis connecting the pair of gripping members 50 so as to be openable and open, and reference numeral 53 denotes a bearing portion 54 so that the front end portions of both gripping members are always in an open direction. Pushing coil spring. Reference numeral 55 denotes a plate-like body 55 facing each other by fitting into openings 56 formed at the front end portions of both gripping members 50, and reference numeral 57 denotes a heater plate in close contact with the rear surface of the plate-like body 55. As shown in FIG.

FIG. 6: is a front view which shows the positional relationship of the heater board 57 and the plate-shaped body 55 taken out from the heating apparatus 51 of FIG. 5, and FIG. The heat of the heater plate 57 is transmitted to one main surface 55b of the plate-like body 55 through one main surface 57a of the heater plate 57, and thus the heating surface 55a which is the other main surface of the plate-like body 55. Can be heated uniformly.

By setting it as such a structure, the plate-shaped object 55 which has the wide heating surface 55a can be heated efficiently and uniformly using the small ceramic heater board 57. As shown in FIG.

The hair iron of FIG. 5 can press the gripping member 50 with a finger to sandwich the hair between the plate-like bodies 55 to heat the hair evenly.

That is, the heating apparatus 51 of this Embodiment 2 has the plate-shaped object provided with the heater plate 57 which embedded the resistance heating body 58 in the plate-shaped ceramic body, and the heating surface 55a which heats a to-be-heated object ( 55, which is a heating device 51 in which one main surface 55b of the plate-like body 55 and one main surface 57a of the heater plate 57 come into contact with each other. In the present invention, the heating surface 55a comprises a flat portion and a chamfered portion of a C surface or a curved surface provided at the periphery thereof, and the thickness H of the heater plate 57 is 0.5 to 5 mm. In the heater plate 57, the resistance heating element 58 is embedded in the plate-shaped ceramic body, and the resistance heating element 58 is blocked from the air to prevent the resistance heating element 58 from being corroded by moisture or the like contained in the air. can do. In addition, the resistive heating element 58 embedded in the plate-shaped ceramic body generates joules at a predetermined temperature when a constant electric power is applied by its own electrical resistance, thereby causing the heater plate 57 to be a heating element. The temperature can be raised to the required predetermined temperature.

Further, since the heating surface 55a is formed of a flat portion and a C surface or a curved chamfer provided at the periphery thereof, there is little risk of damaging the heated object even if the heated object is inserted while sliding on the heating surface 55a. Thus, when the to-be-heated thing is hair, in order to make it hard to damage a hair, when the said chamfer part is C surface, the magnitude | size Wc is preferable in it being 0.1-5 mm, More preferably, it is 0.3-4 mm. More preferably, it is 1-3 mm. In the case where the chamfered portion is a curved surface, it is preferable to form an arc or a secondary curve in a cross section perpendicular to the end surface, so that if the width Wr is 0.2 to 5 mm, damage to the heated object is reduced. Do. More preferably, it is 0.3-4 mm, More preferably, it is 1-3 mm.

Moreover, if the thickness H of the heater plate 57 is 0.5-5.0 mm, the heat of the heater plate 57 can be efficiently transmitted to the plate-like body 55. If the thickness of the heater plate 57 is less than 0.5 mm, since the flatness of one main surface of the plate-shaped body 55 is 0.02 to 0.2 mm, a stress is applied when the heater plate 57 is attached, and the heater plate 57 is It may be damaged.

In addition, when the thickness of the heater plate 57 exceeds 5 mm, even if the heater plate 57 is attached to the plate-shaped body 55, one main surface 57a of the heater plate 57 does not deform, and the heater plate is It is because the one main surface 57a of 57 and the one main surface 55b of the plate-shaped body 55 cannot contact widely, and the heating surface 55a of the plate-shaped body 55 cannot be heated uniformly.

Therefore, when the thickness of the heater plate 57 is 0.5 to 5 mm, one main surface 57a of the heater plate 57 and one main surface 55b of the plate-like body 55 are deformed, respectively, so that the heating surface 55a is widened. Can be heated to uniform temperature. More preferably, the thickness of the heater plate 57 is 1-3 mm.

Moreover, it is preferable to provide the heat transfer member 63 between one main surface 55b of the plate-shaped body 55 and one main surface 57a of the heater plate 57. The heat transfer member 63 facilitates heat transfer between the one main surface 57a of the heater plate 57 of the surface roughness Ra and the one main surface 55b of the plate-like body 55, and the heater plate 57 becomes easier. It is preferable to be able to transfer the heat of) to the plate-like body 55 efficiently.

It is preferable that the heat-transfer member 63 is resin which mixed the silicon type resin or the metal fine powder with a high thermal conductivity. As said metal fine powder, gold, silver, copper, and nickel are preferable because they have large thermal conductivity, More preferably, they are silver. Moreover, silicon resin and a fluororesin can be used as resin. Further, the heat transfer member can eliminate the gap between one main surface 55a of the plate-like body 55 and one main surface 57a of the heater plate 57, and the plate-like body 55 and the heater plate 57 can be removed. It is preferable to prevent the temperature difference between the heating surface 55a from becoming large without changing the thermal conductivity between the main surface 55a and the main surface 57a by the heat transfer member 63 even if the expansion and contraction shift due to the thermal expansion difference is caused.

Moreover, it is preferable that the surface roughness Ra of the one main surface 57a of the heater plate 57 is 1-30 in the heating apparatus 51 of this invention. If the surface roughness Ra of one main surface 57a of the heater plate 57 is less than 1.0, it is difficult to transfer heat evenly through the contact surface with the plate-like body 55, and thus the in-plane temperature difference of the heated surface 55a. This is because there is a fear that it will grow. When the surface roughness Ra is more than 30, the surface roughness may be too large to cause a substantial contact area with the plate-like body 55 to be unable to uniformly heat the plate-like body 55. More preferably, the surface roughness Ra of one main surface of the heater plate 57 is 3-10.

The heating apparatus 51 of FIGS. 5 and 6 presses the heater plate 57 with the claw 55c of the plate-shaped body 55 to make the plate-shaped body 55 and the heater plate 57 contact (FIG. 7). Instead of pressing the heater plate 57 directly with 55c, as shown in Fig. 8, the heater plate 57 is pressed by the spring 59 fixed to the claw, so that one main surface 55b of the plate-like body 55 and the heater plate ( One main surface 57a of 57 may be elastically pressed to make contact. Since the main surface of the heater board 57 and the plate-shaped body 55 can be contacted in a wide range by setting multiple press parts of the spring 59, it is preferable. And it is preferable that the spring 59 is comprised by the leaf spring provided with the some point.

Moreover, it is preferable that the plate-shaped ceramic body of this invention is a ceramic whose main component is either aluminum oxide, mullite, or silicon nitride. The ceramic is preferable because of its relatively high thermal conductivity, excellent corrosion resistance, and high insulation resistance at high temperatures.

Moreover, when a plate-shaped ceramic body is aluminum oxide, it is preferable that the aluminum oxide content is 80-98 mass%. This is because the thermal conductivity of the plate-shaped ceramic body is 16.7 to 25.21 W / (m · K), the high temperature insulation resistance at 300 ° C. is greater than 10 ¹³ Ω · cm, and the bending strength increases to 300 MPa or more. This is because when the aluminum oxide content is less than 80% by mass, sintering aids and impurities such as Mn, Ca, and Si increase, which may lower the insulation resistance at high temperatures.

When the aluminum oxide content exceeds 99.5% by mass, it is difficult to sinter densely at a relatively low temperature of 1700 ° C. or less, and it is difficult to mass-produce at low cost.

Moreover, it is preferable that the plate-shaped object 5 of this invention is a conductive metal. This is because the metal has a high thermal conductivity of 200 W / (m · K) or more, and can uniformly transfer the heat of the heater plate 7 to the heating surface 55a. As said metal, aluminum, iron, or these alloys are preferable. The coefficient of thermal expansion of the plate-shaped body 5 made of metal is preferably 8 to 25 × 10 ⁻⁶ / ° C. or lower, but in particular, the range of 8 to 17 × 10 ⁻⁶ / ° C. close to the coefficient of thermal expansion of the plate-shaped ceramic body 57. Is preferred. Due to the difference in thermal expansion between the plate-shaped body 55 and the heater plate 57, the interval between the main surface 57a and the main surface 55b becomes uneven, which may prevent thermal conduction uniformly and impair the uniformity of the temperature distribution. Because. In addition, the heated object is brought into contact with the heated surface 55a to transfer heat from the heated surface 55a to the heated object. However, the heated surface 55a slides while the heated object and the heated surface 5a are in contact with each other. Although static electricity may generate | occur | produce in this, if electroconductivity exists in the heating surface 55a, it is preferable because it has the effect of escaping this static electricity.

Moreover, it is preferable that the area of the contact surface which the plate-shaped object 55 and the heater plate 57 contact is 20 to 80% of the area of the heating surface 55a. This is because if it is less than 20%, the heating surface 55a of the plate-like body 55 may not be evenly heated. Moreover, when the area of the contact surface which the plate-shaped object 55 and the heater plate 57 contact exceeds 80% of the area of the heating surface 55a, the heater board 57 will become large and the price of the heating apparatus 51 will be high. This is because it may become difficult to use industrially. More preferably, the area of the contact surface is 30 to 60% of the area of the heating surface 55a.

Moreover, it is preferable that the thickness B of the plate-shaped body 55 is 0.2-10 mm. When the thickness is smaller than 0.2 mm, when the plate spring 59 is fixed to the heater plate 57, the strength is small so that the plate-shaped body 55 is deformed to generate a gap, or a problem such as one contact occurs. This is because there is a fear that the in-plane temperature difference of) increases. If the thickness of the plate-shaped body 55 exceeds 10 mm, the heat capacity increases, and even if the heater plate 57 is heated, the temperature of the heating surface 55a of the plate-shaped body 55 may not be raised quickly. The thickness B is more preferably 1 to 3 mm.

In addition, the thickness of the heater plate 57 can be represented by the average value of three points in the distance between the main surface 55b and the main surface 55a.

The plate-like body 55 is preferably made of a metal having a thermal conductivity of 200 W / (m · K) or more. However, the plate-like body 55 is provided with a claw 55c at its periphery so as to be in surface contact with the heater plate 57, and has a thickness of the periphery. It is preferable to make it large, and to enlarge a heat capacity and to make small the temperature difference of a heating surface.

Next, the manufacturing method and other structure of the heating apparatus 51 of this invention are demonstrated.

The heater plate 57 is made of heat-resistant ceramics such as an aluminum oxide sintered compact, a mullite sintered compact, and a silicon nitride sintered compact. For example, the heater plate 57 is made of aluminum oxide (Al ₂ O ₃ ), silica (SiO). ₂ ) A suitable organic solvent and a solvent are added to and mixed with calcium oxide (CaO) and magnesium oxide (MgO) to form a slurry, which is then formed into a sheet by the conventional doctor blade method or calender roll method to form a ceramic green sheet. Get Next, an appropriate punching process is performed on the ceramic green sheet.

The resistive heating element 58 is made of a metal material such as tungsten or molybdenum, and a resistive heating element paste obtained by adding and mixing a suitable organic solvent and a solvent to the metal powder such as tungsten is known in advance to a ceramic green sheet made of a plate-shaped ceramic body. The resistive heating element 8 can be embedded in the plate-shaped ceramic body by printing and coating in a predetermined pattern by the screen printing method. And the raw heater plate which embed | buried the resistance heating body 58 can manufacture the heater plate 7 by baking at high temperature (about 1600 degreeC). At this time, in order to obtain the surface roughness, it is preferable to adjust the firing temperature and time so that the crystal size of the surface of the heater plate 57 is 0.5 to 5 µm.

Both ends of the resistance heating element 58 are led to the end of the heater plate 57, and both ends led to the end are exposed by the opening A formed in the plate-like body 57, and the lead wire 61 is soldered or the like. Is soldered through the solder material. The opening A exposing both ends of the resistive heating element 58 serves to form a region for soldering the resistive heating element 58 and the lead wire 61, and is previously punched into a ceramic green sheet made of a plate-shaped ceramic body. The hole is formed at the end of the heater plate 57 by forming a hole. In the opening A, a concave portion 62 having a size corresponding to the diameter of the lead wire 61 is formed on the sidewall thereof, and the resistance heating element 58 and the lead wire 61 are soldered in the opening A. At this time, when the lead wire 61 is inserted into the recess 62 formed in the side wall of the opening A, the lead wire 61 can be accurately positioned at the center of the upper surface of the resistance heating element 58 exposing the lead wire 61. The 61 can be very firmly soldered to the resistance heating element 58 through the solder material 61.

The lead wire 61 soldered to the resistance heating element 58 in the opening A is made of metal such as nickel, and the lead wire 61 connects the resistance heating element 58 to an external electric circuit. It serves to supply the resistive heating element 58 from the external electric circuit with a constant power necessary to generate Joule heat generation at a predetermined temperature.

The lead wire 61 is brought into contact with the center of the upper surface of the resistive heating element 58 to be exposed accurately by using the recess 62 formed in the side wall of the opening A, and the solder material 61 such as solder melted at the contact portion thereof. It is firmly soldered to the resistance heating element 58 by supplying.

In this way, according to the heating apparatus 51 of this invention, it supplies a constant electric power to the resistance heating body 58 via the lead wire 61, and functions as a heating body by generating heat by generating the resistance heating body 58 to constant temperature.

In addition, this invention is not limited to the said Example, A various change is possible as long as it does not deviate from the summary of this invention, For example, in the above-mentioned Embodiment 2, solder etc. are exposed to the resistive heating element 58 exposed. Although the lead wire 61 was attached through the solder material, the attachment may be reinforced by filling the opening A with resin, glass, or the like, or by filling the opening A with a heat resistant material and covering it with an insulating plate. All. In this case, the resistance heating element 58 and the lead wire 61 are more firmly attached, which is preferable. In addition, in the above-described embodiment, the lead wire 61 is attached to the resistance heating element 58 through a solder material such as solder, but the lead wire 61 is brought into contact with the resistance heating element 58, and the contact is opened. You may adhere by filling and holding resin, glass, etc. in it.

The heating device 51 is brought into contact with the metal plate-like body 55 through silicon grease or the like, but at this time, the thickness of the cushioning material, which is also the heat transfer member 63 of the plate-like body 55 and the ceramic heater plate 57, is 5 to 5. It is preferable that it is 100 micrometers. This is because the ceramic heater plate 57 and the metal heater plate 57 are brought into direct contact with the ceramic iron plate 57 and the plate-shaped body 57 for the hair iron iron. Due to the warpage of the plate-shaped body 55 and the deformation caused by thermal expansion during heating, the joining surfaces did not come into contact uniformly but contacted with each other, causing thermal conductivity to occur in spots, resulting in a large temperature difference between the heating surfaces 55a. The thickness of the shock absorbing material, which is the heat transfer member 63, may be as small as necessary. On the contrary, even if the thickness is too thick, there is a possibility that the thermal conductivity of the ceramic heater and the metal plate may deteriorate. Therefore, the thickness of the heat transfer member 63 is preferably 1 to 100 µm.

In the hair iron of Embodiment 2 described above, the heater plate 57 has a conductor pattern having a return portion constituting the heat generating resistor 4 described in Embodiment 1, and is provided between any conductors adjacent to the return portion. It is preferable that the void occupancy ratio of the ceramic body is 0.01 to 50% (for example, a heater plate made of a plate-shaped ceramic heater shown in FIG. 4 of Embodiment 1 is used). In this way, since the durability of the heater board 57 can be made high, the hair iron with higher durability can be provided. Moreover, the void occupancy rate of the ceramic body between arbitrary conductors adjacent in the return part is more preferably 0.1 to 40%, still more preferably 1 to 20%.

Example 1

A ceramic green sheet having Al ₂ O ₃ as its main component and adjusted to within 10% by weight of SiO ₂ , CaO, MgO, and ZrO ₂ was prepared, and a paste made of a W (tungsten) powder binder and a solvent was prepared on this surface. The heat generating resistor 4 and the lead lead portion 5 were printed.

Moreover, the electrode pad 7 was printed on the back surface. The heat generating resistor 4 was produced so as to have a pattern of 4 reciprocations with a heat generation length of 5 mm.

And in order to fill an insulator between conductors, the paste containing an insulator was performed by screen printing. At this time, in order to change the void occupancy of the ceramic body between conductors, the thing which did not perform screen printing and the thing which performed screen printing by changing the viscosity of a paste was prepared.

Through-holes 6 were formed at the ends of the lead lead-out portions 5 formed of W, and the paste was injected therein to obtain conduction between the electrode pads 7 and the lead lead-out portions 5. The position of the through hole 6 was formed so as to enter the inside of the soldered portion when soldering was performed.

The ceramic green sheet thus prepared was brought into close contact with the periphery of the ceramic molded body and fired at 1600 ° C. to obtain the ceramic heater 1.

About the ceramic heater 1 obtained in this way, durability was evaluated by measuring the resistance change after performing continuous electric current of 1200 degreeC for 100 hours. Each lot n = 10 was evaluated.

The change in the resistance value of 15% or more with respect to the initial resistance value was counted as disconnection.

Moreover, about the sample of each lot n = 3, the cross section of the heat generating resistor 4 after baking was observed by SEM, and the void ratio was measured. These results are shown in Table 1.

Sample No Void rate Void length Heater shape Pattern thickness Evaluation results Judgment *One 0.005 1/10 Cylinder 10 16 × 2 0.01 1/10 Cylinder 20 13 ○ 3 0.1 1/10 Cylinder 20 10 ○ 4 One 1/10 Cylinder 20 8 ◎ 5 10 1/10 Cylinder 20 6 ◎ 6 20 1/10 Cylinder 20 7 ◎ 7 40 1/10 Cylinder 20 11 ○ 8 50 1/10 Cylinder 20 14 ○ * 9 60 1/10 Cylinder 20 17 × 10 10 3/10 Cylinder 20 11 ○ 11 10 1/2 Cylinder 20 13 ○ 12 10 1/10 Plate shape 20 8 ◎ 13 10 1/10 Cylinder 3 14 ○ 14 10 1/10 Cylinder 5 10 ○ 15 10 1/10 Cylinder 70 11 ○ 16 50 1/10 Cylinder 110 14 ○

The material of each sample is all aluminum oxide, and the sample marked * is outside the scope of the present invention.

As can be seen from Table 1, in the sample No9 in which the void occupancy rate of the ceramic body between the conductors exceeds 50%, and in the sample No1 having a void occupancy rate of 0.005%, a disconnection in which the resistance value changes by 15% or more is changed. happened. On the other hand, disconnection did not generate | occur | produce for the sample with a void occupancy of 50% or less, and showed favorable durability.

If the void occupancy is within the range of the invention, there was no significant difference in durability even if the void length and ink thickness of other factors changed.

Example 2

First, in order to obtain a ceramic heater plate as shown in Fig. 9, Al ₂ O ₃ is used as a main component, and W is made of a ceramic sheet in which SiO ₂ , CaO, MgO, and ZrO ₂ are adjusted to be within 10% by weight in total. A resistive heating element was printed. The opening A exposing both ends of the resistive heating element serves to form a region for soldering the resistive heating element and the lead wire, and a hole is formed in the ceramic green sheet serving as the heater plate in advance by a punching process to the end of the heater plate. Is formed. The opening A is further provided with a recess having a size corresponding to the diameter of the lead wire on its side wall, and is used for soldering the lead portion and the lead wire of the resistance heating element in the opening A. FIG. Subsequently, after forming the coating layer which consists of a component substantially the same as a ceramic sheet on the surface of a resistive heating element, and drying enough, the adhesive liquid which disperse | distributed the ceramics of substantially the same composition as the said ceramic sheet was apply | coated, and the ceramic sheets prepared in this way were It laminated | stacked and closely contacted and baked at 1500-1600 degreeC.

Further, after forming a plating layer having a thickness of 3 μm made of Ni on the surface of the lead-out portion of the resistance heating element, the lead wire 61 containing Ni as a main component is 1030 ° C. using a solder material 62 made of Ag. Was bonded to obtain a heater plate.

The heater plate and the plate-shaped object obtained by the above method were combined, and the hair iron which changed the thickness, surface roughness (Ra) of a heater plate, the presence or absence of a spring press, the presence or absence of a heat transfer member, and a material was produced.

The temperature distribution of the surface of the heating surface of the manufactured hair iron was measured by a Nippon Densitizer (TG-6200) temperature distribution measuring device, and the maximum and minimum temperatures of the surface of the heating surface were calculated to calculate the maximum temperature. The difference between and minimum temperature was measured as the temperature deviation.

The results are shown in Table 2.

Sample No. Heater plate thickness (mm) Heating member Surface roughness of heater plate (Ra) Spring press Heating surface temperature deviation (℃) *One 0.3 radish One radish damage *2 0.3 radish 10 radish damage 3 0.5 radish 2 radish 19 4 0.5 radish 2 radish 19 5 0.5 Silicon-based resin 0.5 radish 16 6 0.5 Silicon-based resin One radish 15 7 0.5 Silicon-based resin 3 U 13 8 One Silicon-based resin 6 U 12 9 One Silicon-based resin 10 U 13 10 One Silicon-based resin 20 radish 14 11 One Silicon-based resin 30 radish 14 12 3 Silicon-based resin 40 radish 16 13 5 Metal particulate 3 radish 11 14 5 radish 3 radish 19 15 5 radish 3 radish 19 * 16 7 radish One radish 22 * 17 7 radish 10 radish 24

It evaluated at plate-shaped thickness 1.5mm, plate-shaped heater board contact area, and the heating surface area ratio of 70%.

In addition, * mark shows out of the scope of the present invention.

As can be seen from Table 2, as in Sample Nos. 3 to 15, the sample having a thickness of the heater plate of 0.5 to 5 mm exhibited excellent characteristics with a small temperature deviation of the heating surface of less than 19 ° C.

On the other hand, Sample Nos. 1 and 2 had a small heater plate thickness of 0.3 mm, and when the heater plate was loaded on the plate-like body, the heater plate was broken. Moreover, as for sample Nos. 16 and 17, the thickness of a heater plate was not preferable because the heating surface temperature deviation was 22 degreeC or more.

Moreover, it turned out that the sample Nos. 5-13 provided with the heat-transfer member between a plate-shaped object and a heater board are preferable because the temperature deviation is further smaller with 16 degrees C or less of heating surface temperature.

Moreover, it turned out that the sample Nos. 6-11 whose surface roughness of the main surface of a heater plate are 1-30 micrometers are more preferable because the temperature deviation of a heating surface is small below 15 degreeC.

Moreover, it turned out that the sample Nos. 7-9 which pressed the one main surface of the plate-shaped object and the one main surface of the heater board by the spring have a heating surface temperature deviation of 13 degrees C or less, and the temperature deviation improved.

Example 3

Next, to prepare a heater plate in a manner adjusted to produce a ceramic sheet between the content of the main component of Al ₂ O ₃ of the heater board 70% ~ 99.8%, and those described in Example 2. High-temperature insulation strength and flexural strength at 200 ° C. were measured with materials having different amounts of Al ₂ O ₃ . The flexural strength was produced by measuring 20 test pieces, measuring them according to the 4-point flexural strength test of the JIS standard, and indicating the average values.

Sample No. Aluminum oxide content rate (%) High temperature insulation resistance burglar 21 70 10 ¹⁰ Ω · ㎝ or more 250 MPa 22 75 10 ¹¹ Ω · ㎝ or more 275 MPa 23 80 10 ¹³ Ω · ㎝ or more 300 MPa 24 90 10 ¹³ Ω · ㎝ or more 310 MPa 25 99.5 10 ¹³ Ω · ㎝ or more 320 MPa 26 99.8 10 ¹³ Ω · ㎝ or more 328 MPa

As can be seen from Table 3, samples Nos. 23 to 25 having an aluminum oxide content of 80 to 99.5% have a high temperature insulation resistance of 1 × 10 ¹³ Ω · cm or more, so that a short circuit from the heater heating power supply can be used as a hair iron. It was found that this was more desirable because there was no. Moreover, it was found that the bending strength is 300 MPa or more, so that even if the resistance heating element is repeatedly heated rapidly, there is little possibility of being damaged by thermal stress, and thus it is preferable.

However, when the aluminum oxide content was as low as 70 and 75% by mass as in Sample Nos. 21 and 22, the insulation resistance at high temperature was less than 10 ¹¹ Ω · cm, and there was a risk of leakage through the heater plate. In addition, Sample No. 26 had an aluminum oxide content of 99.8% by mass, which required sintering at a firing temperature of 1700 ° C or higher, and it was difficult to mass produce at low cost.

More preferably, as shown in Sample Nos. 24 and 25, when the aluminum oxide content was 90 to 99.5%, the flexural strength was found to be large.

In addition, aluminum oxide content was calculated | required by ICP quantitative analysis of the produced plate-shaped ceramic body.

Example 4

Next, the hair iron which fixed the external shape of the plate-shaped object to 4 mm x 80 mm x 20 mm (thickness x length x width), changed the length of the heater board to the gradation, and changed the contact area and heating area ratio is Example 2 Like produced.

Then, a silicon-based resin is provided as a heat transfer member between the heater plate and the plate-like member, and the time is applied to the resistance heating element while pressing with a spring, and the time from the room temperature to the saturation temperature of 200 ° C. at the maximum temperature of the heating surface. Was measured as the heating surface saturation time.

The results are shown in Table 4.

Sample No. (Plate-shaped heater plate contact area / heating area) Ratio (%) Plate Shape Thickness (mm) Saturated time of heating surface (sec) 31 5 2 68 32 10 2 63 33 20 3 60 34 30 3 57 35 50 0.1 56 36 50 0.2 50 37 50 One 46 38 50 4 46 39 50 10 47 40 50 12 52 41 60 3 53 42 80 4 60 43 100 4 65

From Table 4, it was found that Sample Nos. 33 to 42 having an area ratio of 20 to 80% exhibited excellent characteristics because the heating surface saturation time was less than 60 seconds or less.

Further, it was found that Sample Nos. 34 to 41 having an area ratio of 30 to 60% exhibited more excellent characteristics because the heating surface saturation time was less than 57 seconds.

On the other hand, Sample Nos. 31 and 32, in which the ratio of the contact area between the heater plate 7 and the plate-like body 5 and the heating surface contact area were less than 20%, were not preferable because the saturation time was 63 seconds or more.

In addition, as in sample No. 43, when the contact area exceeded 80%, the heater plate became too large and the cost of the heater plate became high, resulting in low industrial use value.

Moreover, it turned out that the sample Nos. 36-39 whose thickness of plate-shaped object is 0.2-10 mm are preferable because the heating surface saturation time is small to 50 second or less.

Claims (20)

A ceramic body having an outer surface and a buried conductor pattern, The conductor pattern is made of a conductor provided to form a return portion to form a resistance heating element, the ceramic heater, characterized in that the void portion of the ceramic portion sandwiched by the adjacent conductor in the return portion is 0.01 to 50%. The ceramic heater according to claim 1, wherein the length along the outer surface of the void existing between the adjacent conductors is equal to or less than half the length of the gap between the conductors. The ceramic heater according to claim 1 or 2, wherein the thickness of the conductor is set in a range of 5 to 100 µm. Forming a conductive paste in a predetermined pattern on the surface of the first ceramic green sheet: A ceramic green sheet laminate is produced by laminating a second ceramic green sheet having a thickness at least the same as that of the conductor pattern on the surface on which the conductor paste of the first ceramic green sheet is formed and which is more flexible than the first ceramic green sheet. Process of doing; Bonding the ceramic green sheet laminate to a ceramic molded body; and And a step of firing the bonded ceramic green sheet laminate and the ceramic formed body. Forming a conductor paste in a predetermined pattern on the surface of the ceramic green sheet; Filling an insulator between the conductor pastes in the predetermined pattern; Bonding a ceramic green sheet filled with an insulator between the conductor pastes to a ceramic molded body using a surface on which the conductor paste is formed as a bonding surface; and And a step of firing the bonded ceramic green sheet and ceramic formed body. The method for manufacturing a ceramic heater according to claim 5, wherein the step of filling the insulator is performed by screen printing a paste. The method of manufacturing a ceramic heater according to claim 5, wherein the step of filling the insulator is performed using a dispenser. A heater plate made of a plate-shaped ceramic body in which a resistance heating element is embedded, and having a thickness in a range of 0.5 to 5.0 mm; It has a 1st and 2nd surface, The said heater plate is provided in the 1st surface, The said 2nd surface is a heating surface, The heating surface is provided with the plate-shaped object which consists of a flat part and the chamfer part of the periphery, It is characterized by the above-mentioned. Heating device. The heating apparatus according to claim 8, wherein a heat transfer member is provided between the first surface of the plate-like member and the heater plate. The heating apparatus according to claim 9, wherein the heat transfer member is a resin containing silicon-based resin or metal fine particles. The heating apparatus according to any one of claims 8 to 10, wherein a surface roughness Ra of a surface of the heater plate that faces the first surface is in a range of 1 to 30 µm. The heating apparatus according to any one of claims 8 to 11, comprising means for pressing the plate-shaped body and the heater. The heating apparatus according to any one of claims 8 to 12, wherein the plate-shaped ceramic body is composed mainly of any one of aluminum oxide, mullite, or silicon nitride. The heating apparatus according to claim 13, wherein the plate-shaped ceramic body contains aluminum oxide as a main component, and the aluminum oxide content is 80 to 99.5 mass%. The heating apparatus according to any one of claims 8 to 14, wherein the plate member is made of metal. The heating apparatus according to any one of claims 8 to 15, wherein an area of a contact portion where the plate-shaped body and the heater plate are in contact is 20 to 80% of the area of the heating surface. The heating apparatus in any one of Claims 8-16 whose thickness of the said plate-shaped object is 0.2-10.0 mm. The heating apparatus according to any one of claims 1 to 3 and 8 to 17, wherein the hair is a heated object. The hair iron provided with the ceramic heater as described in any one of Claims 1-3, or the heating device as described in any one of Claims 8-17. 18. A pair of gripping members connected to each other so as to be able to be opened, and each of the ceramic heaters according to any one of claims 1 to 3 or any one of claims 8 to 17 is provided at the front end of the gripping member. The hair iron provided with the heating apparatus of description.

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