JP7069392B1 - RF tag with heat resistance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an RF tag having heat resistance capable of realizing stable tracking with a simple configuration. SOLUTION: An RF tag 10 having heat resistance having an IC chip 11 and an antenna 12 having an inlay 14 arranged on a sheet-shaped base material 13 has a sheet-shaped base material 13 having heat resistance and an inlay 14 having silicic acid. Since the heat-resistant glass 15 is coated with the heat-resistant glass 15 containing the above-mentioned main component and the surface of the heat-resistant glass 15 is exposed to the outside, stable tracking can be realized with a simple configuration. [Selection diagram] Fig. 1

Description

The present invention relates to an RF tag having heat resistance.

For example, in automobile manufacturing factories, there is an increasing need for RFID (Radio Frequency Identification) as a tracking means in a painting line.
The drying temperature of the drying furnace installed in the painting line is high (for example, 150 ° C or higher), and in order to cope with this, the use of heat-resistant RF tags whose surroundings are covered with a cover such as resin is being considered. (For example, see Patent Document 1).

International Publication No. 2012/032696

However, stable tracking could not be realized even by using the conventional heat-resistant RF tag.
For example, in a steel mill, there is a pickling process (a process of washing away the scale on the surface of a steel sheet) in a production line of a steel sheet or the like, and an RF tag having acid resistance (chemical resistance) is also required.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide an RF tag having heat resistance capable of realizing stable tracking with a simple configuration.

The present inventors investigated the reason why stable tracking could not be realized by using a commercially available heat-resistant RF tag.
First, the RF tag is heat-treated in a heating furnace and then taken out, and the result of investigating the transition of the surface temperature thereof will be described with reference to FIG. The RF tag is one in which the entire inlay where the IC chip and antenna are placed on the base material is covered with a heat-resistant cover (composed of resin (PEEK (polyetheretherketone), heat-resistant nylon, etc.)). (The inlay is sealed with a cover), and three types of heat-resistant specifications (175 ° C: ◆, 250 ° C: ■, 300 ° C: ▲) RF tags were used here.
As shown in FIG. 8, it was found that the higher the temperature of the heat-resistant specification, the longer it takes for the surface temperature of the RF tag (cover covering the surroundings) to decrease (decrease). That is, the heat-resistant RF tag does not easily heat the inside of the cover (near the IC chip), but tends to be difficult to cool when heated.

Next, the RF tag was charged into the heating furnace (heat treatment) and taken out multiple times, and the time required for the RF tag to return to operation (operable as a semiconductor) was measured each time it was taken out, see FIG. 9. I will explain while doing. The heat treatment was 250 ° C. × 1 Hr. Further, as the RF tag, the entire inlay was covered with the above-mentioned cover, and here, three types of RF tags (○, Δ, ●) having a heat resistance specification of 300 ° C. were used.
As shown in FIG. 9, it was found that it takes about 10 minutes to recover the operation when the number of heat treatments of the RF tag is up to 2 times. When the number of heat treatments of the RF tag is 3 times or more (particularly 4 times or 5 times), the time required for returning to operation is shortened, but this is because the inside of the cover is sealed when the inlay is sealed with the cover. It is presumed that the thermal expansion of the gas mixed in the cover caused a part of the cover to be damaged to form an opening, and the formed opening cooled the inside of the RF tag.

Therefore, the present inventors have restored the operation of the RF tag by adopting a structure in which the entire inlay is exposed to the outside air, instead of a structure in which the entire inlay is covered with a cover as in the conventional case. I came up with the idea of shortening the time required for this.
The RF tag IC chip can operate as a semiconductor because it has a constant conductivity up to a temperature of about 150 ° C., but when the temperature exceeds 150 ° C., the conductivity decreases and it becomes a mere resistor. There is. Therefore, it is also necessary to configure the IC chip so that the temperature of the IC chip is 150 ° C. or lower even if the RF tag is heated.
The present invention has been made based on the above findings, and the gist thereof is as follows.

The heat-resistant RF tag according to the present invention according to the above object is a heat-resistant RF tag having an inlay in which an IC chip and an antenna are arranged on a sheet-like substrate.
The sheet-like substrate has heat resistance, and the inlay is coated with heat-resistant glass containing silicic acid as a main component, and the surface of the heat-resistant glass is exposed to the outside.
Here, it is preferable that the RF tag further has chemical resistance.

In the heat-resistant RF tag according to the present invention, the sheet-like base material is preferably made of polyimide.
In the heat-resistant RF tag according to the present invention, the sheet-like substrate is preferably made of polyetheretherketone (PEEK).
In the RF tag having heat resistance according to the present invention, the sheet-like base material is coated paper, and the coated paper is impregnated with the heat-resistant glass (the surface of the coated paper is further covered with heat-resistant glass). It is preferably coated).

In the heat-resistant RF tag according to the present invention, the surface of the heat-resistant glass coated with the inlay is covered with a cover member having heat resistance and insulation, and the cover member is covered with the heat-resistant glass. It is preferable that a ventilation portion is formed to expose a part of the surface of the glass to the outside air.

Here, it is preferable that the ventilation portion has a ventilation hole A formed in the thickness direction of the inlay.
Further, the ventilation portion may further have a ventilation groove continuously formed in the ventilation hole A on one end surface or both end surfaces of the cover member in the thickness direction of the inlay.
The ventilation portion may further have a ventilation hole B formed in the cover member in a direction orthogonal to the thickness direction of the inlay so as to communicate with the ventilation hole A.

In the heat-resistant RF tag according to the present invention, the sheet-like substrate has heat resistance, the inlay is coated with heat-resistant glass containing silicic acid as a main component, and the surface of the heat-resistant glass is exposed to the outside. Therefore, the heat resistance of the inlay is enhanced, and the inlay can be positively exposed to the outside air through the heat-resistant glass. As a result, the cooling efficiency of the RF tag can be improved as compared with the conventional case, so that the time required for returning the operation of the RF tag can be shortened as compared with the conventional case.
Therefore, it is possible to provide an RF tag capable of realizing stable tracking with a simple configuration.

Here, when the sheet-like base material is made of polyimide, it is effective in an environment of high temperature of, for example, 300 ° C. or higher.
When the sheet-like substrate is made of polyetheretherketone (hereinafter, also referred to as PEEK), for example, in a drying furnace installed in a painting line, the drying temperature is 200 ° C to 260 ° C (the maximum residence time is about about about). It is effective in an environment of about 40 minutes) (particularly, an environment of more than 250 ° C.).
When the sheet-like base material is coated paper, the cost can be reduced, and the coated paper is impregnated with heat-resistant glass having chemical resistance (the surface of the coated paper is further covered with heat-resistant glass). By being coated), the fragility of the coated paper can be reinforced, and the heat resistance and chemical resistance of the inlay can be improved.

In particular, the surface of the heat-resistant glass that coats the inlay is covered with a cover member having heat resistance and insulation, and a ventilation portion that exposes a part of the surface of the heat-resistant glass to the outside air is formed on the cover member. If so, the cover member will not contain the internal gas. The purpose of using this cover member is, for example, to hold an inlay, a spacer for an object to which an RF tag is attached (made of a metal having conductivity), and to prevent damage due to contact or interference with nearby equipment.
This eliminates the problem that the cover member is damaged by the thermal expansion of the gas due to heating as in the conventional case, and the cooling efficiency of the inlay can be improved even if the cover member is used, so that the time required for the RF tag to return to operation is required. Can be shortened.

(A) to (D) are a plan view, a side view, a bottom view, and a front view of the RF tag having heat resistance according to the first embodiment of the present invention, respectively. (A) and (B) are a plan view and a partial side sectional view of an inlay used for the RF tag having heat resistance, respectively. It is a side view of the RF tag provided with heat resistance which concerns on a modification. (A) to (C) are a plan view, a side view, and a bottom view of the RF tag having heat resistance according to the second embodiment of the present invention, respectively. (A) to (C) are a plan view, a side view, and a bottom view of the RF tag having heat resistance according to the third embodiment of the present invention, respectively. It is a graph which shows the transition of the surface temperature of the RF tag taken out after the heat treatment in a heating furnace. It is a graph which shows the time required for the operation of the RF tag to return after being taken out from a heating furnace. It is a graph which shows the transition of the surface temperature of the RF tag which concerns on the conventional example taken out after the heat treatment in a heating furnace. It is a graph which shows the relationship between the number of times of heat treatment of the RF tag which concerns on a conventional example by a heating furnace, and the time required to return the operation of the RF tag which concerns on a conventional example after being taken out from a heating furnace.

Subsequently, an embodiment embodying the present invention will be described with reference to the attached drawings, and the present invention will be understood.
As shown in FIGS. 1 (A) to 1 (D), FIGS. 2 (A), and 2 (B), an RF tag having heat resistance according to the first embodiment of the present invention (hereinafter, also simply referred to as an RF tag). ) 10 has an inlay (dry inlay) 14 in which an IC chip (IC element, semiconductor) 11 and an antenna 12 are arranged on a sheet-like base material 13, and the heat resistance is improved as compared with the conventional case. The time required to return to operation can be shortened. In FIGS. 1 (A) to 1 (D), FIGS. 2 (A), and 2 (B), the sizes of the RF tag 10 and the inlay 14 used for the RF tag 10 are changed for convenience of explanation (FIGS. 3 and 3 described later). 4 (A) to (C) and FIGS. 5 (A) to 5 (C) are also the same).
Hereinafter, it will be described in detail.

The RF tags 10 shown in FIGS. 1A to 1D have heat resistance (heat insulating property) and are suitable for use in a high temperature environment (atmosphere). Here, the high temperature is, for example, 150 ° C. or higher (preferably 200 ° C. or higher, more preferably 250 ° C. or higher, upper limit 350 ° C., further 300 ° C. or higher).
The RF tag may further have chemical resistance suitable for use in an environment (atmosphere) in which chemicals are present, but may not have chemical resistance depending on the usage environment of the RF tag (the RF tag may not have chemical resistance). Only heat resistance is required). Here, the chemical mainly means an acid (sulfuric acid, hydrochloric acid, nitric acid, etc.), but is not particularly limited.
Specific examples of the above-mentioned high-temperature environment include a painting line (drying furnace) in an automobile manufacturing factory, a steelmaking factory (pot) in a steel mill, and examples of an environment in which chemicals exist. There is a pickling process at a steel mill, but it is not particularly limited, and if it is in a high temperature environment or in an environment where chemicals are present, for example, a manufacturing line of a chemical factory, a food manufacturing factory, etc. But it may be.

As shown in FIGS. 1 (A) to 1 (D), FIGS. 2 (A), and 2 (B), the inlay 14 included in the RF tag 10 is on a rectangular (rectangular) sheet-like base material 13 in a plan view. The antenna 12 and the IC chip 11 are arranged therein.
The IC chip 11 (silicon (Si) base) has a well-known structure, and is connected to an antenna 12 made of a conductive metal (copper foil, aluminum foil, etc.) attached on a sheet-like base material 13 and is connected to the IC chip 11 (silicon (Si) base). The structure is such that an identification code specially stored inside is transmitted to the outside wirelessly by an electromotive force obtained by receiving radio waves from a transmitter / receiver (not shown).
The sheet-like base material 13 has heat resistance, and for example, it is preferable to use a polyimide (thermosetting polyimide) film (thin plate or foil, the same applies hereinafter) in a high temperature environment of 300 ° C. or higher. In a lower temperature environment, it is preferable to use a film made of polyetheretherketone (PEEK), and in a lower temperature environment (for example, 150 ° C. or higher and 200 ° C. or lower), it is preferable to use coated paper. As described above, the sheet-like substrate can be appropriately selected depending on the environment in which the RF tag is used, and is not particularly limited. For example, fluororesin (PTFE: polytetrafluoroethylene), polyethylene terephthalate (PET), and the like. It can also be made of a sheet (thin plate or foil) made of epoxy glass (Galaepo) or the like, or other paper or the like.

As described above, when the sheet-shaped base material 13 is made of polyimide, it is preferable that the antenna is made of copper, which has substantially the same coefficient of linear expansion as that of polyimide. In this case, in order to prevent the antenna from peeling off from the sheet-shaped substrate, an adhesive capable of withstanding high temperatures (for example, thermoplastic polyimide (TPI)) may be used to bond the antenna to the sheet-shaped substrate. preferable.
When the sheet-like base material is made of PEEK, the antenna is preferably made of copper, which is close to the coefficient of linear expansion of PEEK (may be made of aluminum).
When the sheet-like base material is made of coated paper, the antenna is preferably made of aluminum having a coefficient of linear expansion equivalent to that of the coated paper (coated paper impregnated with heat-resistant glass described later). This coated paper is, for example, a paper obtained by applying (coating) a white pigment on the surface of high-quality paper to give a gloss, has an ignition point of about 450 ° C., and can withstand the above-mentioned high temperature environment (heat resistance). Has).
In the present embodiment, for example, the thickness of the sheet-shaped base material 13 is about 80 μm, the thickness of the antenna 12 is about 100 μm, and the thickness of the IC chip 11 is about 200 μm, but the thickness is particularly limited. Instead, the thickness of each part of the inlay can be variously changed according to the object or the like on which the RF tag is used.

The inlay 14 is coated with heat-resistant glass 15 containing silicic acid as a main component (a heat-resistant glass film is formed).
The heat-resistant glass 15 is represented by the general formula of M ₂ O · nSiO ₂ , and is mainly composed of silicate (alkali silicate) in which M is any of Na, K, Li, and Cs in the state of the liquid before coating (alkaline silicate). 20 to 50% by weight), and in the presence of metallic alkali (MSiOn), for example, 0.01 to 1.0 mol / kg of ammonium ion and 0.01 to 1.0 mol / kg of halogen ion are added. If necessary, it is preferable to use one diluted with alcohol. Ammonium ion and halogen ion are added to improve the permeability and are not necessarily essential components.
As the heat-resistant glass 15 to be used, specifically, Terios Coat (registered trademark) NP360G released by Nikko Co., Ltd. is preferable. This Terios coat NP360G has the properties of SiO ₂ as a main component, a heat resistant temperature of 700 ° C., and a specific gravity of 1.05.

Since the heat-resistant glass 15 described above covers the entire surface (peripheral surface) of the inlay 14, the heat resistance and chemical resistance of the entire inlay 14 are improved. However, depending on the usage environment of the RF tag, for example, heat resistance By selecting the type of glass, it is only necessary to improve the heat resistance (there is no need for chemical resistance). Here, when the sheet-like base material is made of polyimide or PEEK, the surface of the sheet-like base material is covered with heat-resistant glass, but when the sheet-like base material is made of coated paper, the heat-resistant glass is a sheet. Since the sheet-like substrate is impregnated (penetrated) and further covers the surface of the sheet-like substrate, the heat resistance and chemical resistance of the sheet-like substrate can be improved.
The thickness of the heat-resistant glass 15 coating the inlay 14 (the average thickness of the portion covering the surface of the inlay 14) is not particularly limited as long as it covers the entire surface of the inlay 14, but for example, It may be about 100 μm or less (preferably, the lower limit is about 10 μm and the upper limit is about 50 μm).
As a coating method of the heat-resistant glass 15, there is a method of immersing the inlay 14 in a liquid heat-resistant glass (ditching), but the coating is not particularly limited as long as it can be coated. For example, a mold in which the inlay 14 is arranged. There is also a method of pouring liquid heat-resistant glass into the frame and curing it.

The surface of the heat-resistant glass 15 that coats the inlay 14 is covered with the cover member 16 in a state where a part of the heat-resistant glass 15 is exposed to the outside air (outside).
The cover member 16 is made of a material having heat resistance and insulating properties. Specifically, the fluororesin or PEEK constituting the sheet-like substrate can be used, but it is preferable to use the fluororesin in consideration of heat resistance, chemical resistance, and economy. By selecting the material of the cover member according to the usage environment of the RF tag, the RF tag can be configured to have only heat resistance (it does not have to be chemical resistant).
By covering the surface of the heat-resistant glass 15 with the cover member 16 in this way, for example, the holding of the inlay 14, the spacer for the object to be attached (made of conductive metal) of the RF tag 10, and the contact with the proximity equipment. It can play a role of preventing damage to the inlay 14 due to interference and interference.

The cover member 16 is composed of two plates 17 and 18 having a rectangular shape (same shape) in a plan view, in which the inlay 14 is arranged so as to be sandwiched from both sides in the thickness direction via the heat-resistant glass 15. By fastening 17 and 18 with eight (plural) screws (fastening means) 19, the inlay 14 coated with the heat-resistant glass 15 and the plate members 17 and 18 are integrated. It should be noted that the width of each of the plate members 17 and 18 in a plan view may be sufficient to cover the entire inlay 14, and each thickness may serve the role of the cover member 16 described above. It is about 1 mm to 10 mm (preferably, the lower limit is 2 mm, the upper limit is 5 mm, and here 3 mm).
The shape and structure of the cover member are not particularly limited as long as the entire inlay can be covered with a part of the surface of the heat-resistant glass exposed to the outside air. It may be attached with a single cover member (for example, an insertion hole through which an inlay can be inserted is formed in the center of the cover member in the thickness direction).

As shown in FIGS. 1A to 1D, the cover member 16 has a part of the surface of the heat-resistant glass 15 covering the entire surface of the inlay 14 (partially the surface of the heat-resistant glass 15) outside air. A ventilation portion 20 exposed to (air) is formed. Here, the part of the surface is, for example, 5% or more (preferably 10% or more, 15% or more, 20% or more, and further 50% or more, 70% or more) of the area of one side of the heat-resistant glass 15. The upper limit is not particularly limited, but may be, for example, about 95%, further 90%) (it is preferable to include at least the arrangement area of the IC chip 13).
The ventilation portion 20 has three (plurality) ventilation holes (an example of the ventilation holes A) 21 to 23 formed in the thickness direction of the inlay 14.
The three ventilation holes 21 to 23 have the same shape and have a rectangular shape (may be a square shape) in a plan view. The central portion where the IC chip 11 of the inlay 14 is arranged and both sides thereof (longitudinal length of the inlay 14). It is formed so as to penetrate the cover member 16 in each direction (hereinafter, also referred to as the X direction). The inner width of each of the ventilation holes 21 to 23 in the direction orthogonal to the longitudinal direction of the inlay 14 (hereinafter, also referred to as the Y direction) in a plan view is wider than the width of the inlay 14 in the Y direction.

Further, the ventilation portions 20 are formed in the cover member 16 in a direction orthogonal to the thickness direction of the inlay 14 (side of the inlay 14) so as to communicate with the ventilation holes 21 to 23. It has ventilation holes (an example of ventilation holes B) 24 to 27.
The ventilation holes 24 are formed from one end to the other end of the cover member 16 along the X direction of the inlay 14 (from the left end surface of the cover member 16 (lower end portion of the upper plate member 17 in FIGS. 1A to 1C). (To the right end surface), it is formed so as to communicate with all the ventilation holes 21 to 23. The inlay 14 on the lower plate 18 is pressed onto the plate 18 by a linear protrusion 28 provided at the center of the ventilation hole 24 in the Y direction (upper plate 17), and is pressed from the cover member 16. Although the inlay is prevented from falling off, the configuration of the protrusion is not particularly limited as long as the inlay can be prevented from falling off from the cover member, and for example, a plurality of spots may be provided.
The other ventilation holes 25 to 27 are each from one end to the other end of the cover member 16 along the Y direction of the inlay 14 (in FIG. 1B, the front side of the cover member 16 (the lower end portion of the upper plate member 17)). (From the end face to the back end face), it is formed so as to pass through the ventilation holes 21 to 23.

When the RF tag 10 described above is attached to an object (managed object), the orientation of the RF tag 10 may be horizontal or vertical.
For example, when an RF tag is used in a drying furnace or a heating furnace, if the high-temperature RF tag is exposed to the outside air at room temperature, an updraft is generated by convection. Therefore, in order to promote the circulation of the air, the cover member covering the inlay is provided with a ventilation hole that leads in the vertical direction, so that the outside air can flow inside the RF tag and the temperature drop of the IC chip can be accelerated.
Specifically, when the RF tag 10 attached to the object is in the horizontal state (the X and Y directions are horizontal), it is mainly formed in the thickness direction of the RF tag 10 (inlay 14) (arranged in the vertical direction). The three ventilation holes 21 to 23 allow outside air to flow in the thickness direction of the RF tag 10.
Further, when the RF tag 10 attached to the object is in a vertical state along the X direction, the X of the RF tag 10 is mainly formed by the vent holes 24 formed in the X direction (arranged in the vertical direction) of the RF tag 10. When the outside air can flow in the direction and the RF tag 10 is in a vertical state along the Y direction, the three ventilation holes 25 to 27 formed mainly in the Y direction (arranged in the vertical direction) of the RF tag 10 allow the outside air to flow in the direction. The outside air can flow in the Y direction of the RF tag 10.
When the direction of the RF tag 10 is slanted, the outside air can be allowed to flow through the RF tag 10 by the combination of the plurality of ventilation holes 21 to 27 described above.

Further, the ventilation portion 20 is continuous with the ventilation holes 21 to 23 on one end surface of the cover member 16 (the lower end surface of the lower plate material 18 in FIG. 1B) in the thickness direction of the inlay 14. It has four (s) of ventilation grooves 29 to 32 formed in the above.
The ventilation groove 29 has a concave cross section (opening downward) from one end to the other end of the cover member 16 along the X direction of the inlay 14 (in FIGS. 1A to 1C, the cover member 16 (lower side). (From the left end surface to the right end surface) of the plate material 18), it is formed so as to pass through (cross) all the ventilation holes 21 to 23 and be continuous.
The other ventilation grooves 30 to 32 have the same shape, and each has a concave cross section (opening downward) from one end to the other end of the cover member 16 along the Y direction of the inlay 14 (in FIG. 1B). The cover member 16 (from the front end surface to the back end surface of the lower plate 18) is formed so as to pass through the ventilation holes 21 to 23.

As a result, when the RF tag 10 is attached to the object (not shown), even when the lower end surface of the lower plate 18 constituting the cover member 16 is attached to the surface of the object, the RF tag 10 is attached to the surface of the object via the ventilation grooves 29 to 32. Can form the flow of outside air.
The configuration of the ventilation groove is not particularly limited, and for example, as in the RF tag 10a (ventilation portion 20a) shown in FIG. 3, not only the lower plate material 18 constituting the cover member 16a but also the upper side. It can also be formed on the upper end surface of the plate member 17a (that is, it can be formed on both end faces of the cover member 16a). Here, the four (plurality) ventilation grooves 29a to 32a continuously formed in the ventilation holes 21a to 23a (an example of the ventilation holes A, substantially the same configuration as the ventilation holes 21 to 23) are cover members 16. It has the same configuration as the ventilation grooves 29 to 32 formed in, but may have different shapes and numbers, for example.
As a result, when the RF tag is attached to the object, even if any surface of the cover member in the thickness direction is attached to the surface of the object, the flow of outside air can be formed through each ventilation groove, which is easy to use.

Next, the RF tag (hereinafter, also simply referred to as an RF tag) 40 having heat resistance according to the second embodiment of the present invention will be described with reference to FIGS. 4 (A) to 4 (C). Since the basic configuration is the same as that of the RF tag 10 described above, the same members are designated by the same reference numerals, and different parts will be described in detail.
The surface of the heat-resistant glass 15 that coats the inlay 14 is covered with a cover member 41 (the same material as the cover member 16). The cover member 41 is composed of two plate members 42 and 43 having a rectangular shape (same shape) in a plan view, in which the inlay 14 is arranged so as to be sandwiched from both sides in the thickness direction via the heat-resistant glass 15. By fastening the plate materials 42 and 43 with eight screws 19, the inlay 14 coated with the heat-resistant glass 15 and the plate materials 42 and 43 are integrated.

The cover member 41 is formed with a ventilation portion 44 that exposes a part of the surface of the heat-resistant glass 15 that covers the entire surface of the inlay 14 to the outside air.
The ventilation portion 44 has a ventilation hole (an example of the ventilation hole A) 45 formed in the thickness direction of the inlay 14, and the ventilation holes 22 and 23. The ventilation hole 45 has a rectangular shape (may be a square shape) in a plan view, and is formed so as to penetrate the cover member 41 in the central portion where the IC chip 11 of the inlay 14 is arranged. In the ventilation holes 45, the inner widths of the inlay 14 in the X direction and the Y direction are narrower than those of the other ventilation holes 22 and 23, and the inner width in the Y direction is narrower than the width of the inlay 14 in the Y direction. It has become.

Further, the ventilation portion 44 is formed in the cover member 41 on the side of the inlay 14 so as to communicate with the ventilation holes 45, 22 and 23 (an example of the ventilation holes B) 46, 47, the ventilation holes 26, and the ventilation holes 26. Has 27.
The ventilation holes 46 are formed so as to communicate all the ventilation holes 45, 22, 23 from the left end surface to the right end surface of the cover member 41 (the lower end portion of the upper plate member 42) along the X direction of the inlay 14. ing. Reference numerals 28a shown in FIGS. 4A to 4C are protrusions having the same function as the protrusion 28 described above.
The ventilation hole 47 is formed so as to pass from the front end surface to the back end surface of the cover member 41 (the lower end portion of the upper plate member 42) along the Y direction of the inlay 14.

Further, the ventilation portion 44 is in the thickness direction of the inlay 14, and the ventilation groove 48 formed continuously in the ventilation holes 45, 22, 23 on the lower end surface of the lower plate member 43 constituting the cover member 41. It has 49, ventilation grooves 31, and 32.
The ventilation groove 48 has a concave cross section (opening downward), and all the ventilation holes 45 are formed from the left end surface to the right end surface of the cover member 41 (the lower end portion of the lower plate member 43) along the X direction of the inlay 14. , 22, 23 are formed so as to pass (cross) and be continuous.
The ventilation groove 49 has a concave cross section (opening downward), and the cross section thereof is smaller than the ventilation grooves 31 and 32, and the cover member 41 (the lower end portion of the lower plate material 43) is formed along the Y direction of the inlay 14. It is formed so as to pass through the ventilation hole 45 (from the front end surface to the back end surface).

Subsequently, the RF tag (hereinafter, also simply referred to as an RF tag) 60 having heat resistance according to the third embodiment of the present invention will be described with reference to FIGS. 5 (A) to 5 (C). Since the basic configuration is the same as that of the RF tag 10 described above, the same members are designated by the same reference numerals, and different parts will be described in detail.
The surface of the heat-resistant glass 15 that coats the inlay 14 is covered with a cover member 61 (the same material as the cover member 16). The cover member 61 is composed of two plates 62 and 63 having a rectangular shape (same shape) in a plan view, in which the inlay 14 is arranged so as to be sandwiched from both sides in the thickness direction via the heat-resistant glass 15. By fastening the plate materials 62 and 63 with eight screws 19, the inlay 14 coated with the heat-resistant glass 15 and the plate materials 62 and 63 are integrated.

The cover member 61 is formed with a ventilation portion 64 that exposes a part of the surface of the heat-resistant glass 15 that covers the entire surface of the inlay 14 to the outside air.
The ventilation portion 64 has the ventilation holes 21 described above (the ventilation holes 22 and 23 shown in FIGS. 1A to 1D are not formed on both sides of the ventilation holes 21).
Further, the ventilation portion 64 has a ventilation hole 25 formed in the cover member 61 so as to communicate with the ventilation hole 21 on the side of the inlay 14 (the ventilation holes shown in FIGS. 1A to 1D). 24, 26, 27 are not formed).
Further, the ventilation portion 64 has a ventilation groove 30 continuously formed in the ventilation hole 21 on the lower end surface of the lower plate member 63 constituting the cover member 61 in the thickness direction of the inlay 14. (Ventilation grooves 29, 31, 32 shown in FIGS. 1A to 1D are not formed).
In the above configuration, the facing surfaces (regions other than the ventilation holes 21) of the two plates 62 and 63 come into contact with the surface of the inlay 14 coated with the heat-resistant glass 15, so that the protrusion 28 (projection) is described above. Part 28a) is unnecessary.

In the use of the RF tag 10 (same for the RF tags 10a, 40, 60) described above, the RF tag 10 is attached to the object to be tracked.
Then, when the transmitter / receiver is operated by a computer to perform a reading operation, the transmitter / receiver sends a predetermined high-frequency current to the antenna, and when this high-frequency current is supplied to the antenna, radio waves are radiated from the antenna. This radio wave is a question wave that operates the RF tag 10.
The above-mentioned transmitter / receiver has the same configuration as an existing RF tag reader (reader / writer).
As a result, the RF tag 10 can be operated.

Here, when the RF tag 10 receives the question wave radiated from the antenna, the radio wave (answer wave) transmitted from the RF tag 10 is received by the antenna 12, and the high frequency current representing this answer wave is transmitted to the transmitter / receiver. Entered.
The transmitter / receiver demodulates this high frequency current and reads the data of the RF tag 10.
The above operation is performed based on a program preset in the computer, and the obtained data is sent to the computer and stored.
This makes it possible to track the object.

Next, an example carried out for confirming the action and effect of the present invention will be described.
First, the RF tag is heat-treated to 280 ° C. in a heating furnace and then taken out, and the result of investigating the transition of the surface temperature thereof will be described with reference to FIG.
In the RF tag used, the entire inlay in which the IC chip and antenna are placed on a sheet-like base material (made by PEEK) is coated with heat-resistant glass (Terioscoat (registered trademark) NP360G), and the heat resistance that covers the entire inlay is further covered. The surface of the glass is covered with a cover member (fluororesin: thickness on one side is 3 mm). Here, the three types of RF tags (□ mark, ▲ mark, and ■ mark) according to the examples are used. One type of RF tag (marked with ○) according to the comparative example was used. The three types of RF tags according to this embodiment have various sizes of the ventilation portions (vent holes) formed in the cover member, and the □ marks (openings (large)) are shown in FIGS. 1 (A) to 1 (A). (D), ▲ mark (opening (middle)) corresponds to FIGS. 4 (A) to (C), and ■ mark (opening (small)) corresponds to FIGS. 5 (A) to (C), while comparative examples. One type of RF tag according to the above is one in which a ventilation portion is not formed in the cover member (no opening).
Further, for comparison, the conventional RF tag having a heat resistant specification (300 ° C.) shown in FIG. 8 is shown as a commercially available product.
As shown in FIG. 6, it was found that the cooling effect of the RF tag became remarkable by forming the ventilation portion in the cover member. In particular, the cooling effect of the RF tag was more remarkable as the size of the opening of the ventilation portion was larger.
It is probable that this is because the cover member is provided with a ventilation part (breathability), so that the effect of applying "convection" due to the temperature difference with the outside air when taken out from the heating furnace is obtained.

Subsequently, the result of measuring the time required for the RF tag to return to operation (operable as a semiconductor) after being heat-treated in a heating furnace and taken out will be described with reference to FIG. 7. The heat treatment was 280 ° C. × 1 Hr.
The RF tags used are the three types of RF tags according to the above-described embodiment and the one type of RF tag (A without opening) according to the comparative example. Further, for comparison, the result of heat-treating an RF tag (B without an opening) having a thickness of 5 mm on one side at 250 ° C. × 1 Hr is also described.
As shown in FIG. 7, it was found that by forming the ventilation portion on the cover member, the time required for returning to the operation can be significantly shortened as compared with the case where the ventilation portion is not formed. In particular, the time required to restore the operation of the RF tag is 6 minutes or more without an opening, but it can be shortened as the size of the opening of the ventilation portion increases, and when the size of the opening is the largest, it can be shortened. It turned out that it can be shortened to about 1 minute.
It is considered that this is due to the effect of improving the cooling rate of the RF tag by forming the ventilation portion, which was found from FIG. 6 above.
The cooling effect of the RF tag by the cover member forming the ventilation portion as described above is, for example, the sheet-like base material constituting the inlay, the heat-resistant glass coating the inlay, and the cover covering the surface of the heat-resistant glass. A similar tendency was obtained without being affected by each material of the member.

From the above, it was found that by using the RF tag having the heat resistance of the present invention, the cooling efficiency of the RF tag can be improved as compared with the conventional case, and therefore the time required for the RF tag to recover the operation can be shortened as compared with the conventional case. rice field.
Therefore, stable tracking can be realized even in a high temperature environment (for example, 150 ° C. or higher) or even in an environment where chemicals are present.

Although the present invention has been described above with reference to the embodiments, the present invention is not limited to the configuration described in the above-described embodiments, and the matters described in the claims. It also includes other embodiments and variations that may be considered within the scope. For example, the case where a part or all of the above-described embodiments and modifications are combined to form an RF tag having heat resistance of the present invention is also included in the scope of rights of the present invention.
In the above embodiment, the case where the surface of the heat-resistant glass to be coated with the inlay is covered with a cover member having heat resistance and insulation has been described. However, for example, when the object to which the RF tag is attached is not a metal (conductive). If it does not have the property), it is not necessary to use the cover member. In this case, the RF tag has the configuration shown in FIG. 2 (without the cover member), and the entire surface of the heat-resistant glass is exposed to the outside (exposed to the outside air).

Further, in the above embodiment, the RF tag is a passive type (mounted battery: none) that operates only by the electromotive force obtained by receiving the radio wave from the transmitter / receiver, but by receiving the radio wave from the transmitter / receiver. A semi-passive type that communicates with the obtained electromotive force (mounted battery: Yes (for sensor only)) and an active type that operates with all the power supplied from the built-in (mounted) battery (mounted battery: Yes (communication and sensor) For)).
Further, in the above-described embodiment, the configuration of the ventilation portion formed on the cover member is not particularly limited as long as the required cooling efficiency can be obtained, and for example, the number of ventilation holes and ventilation grooves constituting the ventilation portion and the number of ventilation grooves and the ventilation groove are not limited. The shape can be changed in various ways.

10, 10a: RF tag with heat resistance, 11: IC chip, 12: antenna, 13: sheet-like substrate, 14: inlay, 15: heat resistant glass, 16, 16a: cover member, 17, 17a, 18 : Plate material, 19: Screw, 20, 20a: Vent part, 21-23, 21a-23a: Vent hole (vent hole A), 24-27: Vent hole (vent hole B), 28, 28a: Protrusion part, 29 ~ 32, 29a ~ 32a: Vent groove, 40: RF tag having heat resistance, 41: Cover member, 42, 43: Plate material, 44: Ventilation part, 45: Vent hole (vent hole A), 46, 47: Vent holes (vent holes B), 48, 49: Ventilation groove, 60: RF tag with heat resistance, 61: Cover member, 62, 63: Plate material, 64: Ventilation part

Claims (9)

A heat-resistant RF tag with an inlay in which the IC chip and antenna are placed on a sheet-like substrate.
The sheet-like substrate has heat resistance, and the inlay is coated with heat-resistant glass containing silicic acid as a main component, and the surface of the heat-resistant glass is exposed to the outside. RF tag. The RF tag having heat resistance according to claim 1, wherein the RF tag having heat resistance is further provided with chemical resistance. The RF tag having heat resistance according to claim 1 or 2, wherein the sheet-like base material is made of polyimide. The RF tag having heat resistance according to claim 1 or 2, wherein the sheet-like base material is made of polyetheretherketone. In the RF tag having heat resistance according to claim 1 or 2, the sheet-like base material is coated paper, and the coated paper is impregnated with the heat-resistant glass. RF tag. In the RF tag having heat resistance according to any one of claims 1 to 5, the surface of the heat resistant glass coated with the inlay is covered with a cover member having heat resistance and insulation. The RF tag having heat resistance is characterized in that the cover member is formed with a ventilation portion that exposes a part of the surface of the heat-resistant glass to the outside air. The RF tag having heat resistance according to claim 6, wherein the ventilation portion has a ventilation hole A formed in the thickness direction of the inlay. In the heat-resistant RF tag according to claim 7, the ventilation portion is continuously formed in the ventilation hole A on one end surface or both end surfaces of the cover member in the thickness direction of the inlay. An RF tag having heat resistance, which is characterized by further having a ventilation groove. In the RF tag having heat resistance according to claim 7 or 8, the ventilation portion is formed in communication with the ventilation hole A in a direction orthogonal to the thickness direction of the inlay in the cover member. An RF tag having heat resistance, which is characterized by further having pores B.

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