Joint, detector for infrared gas analyzer, infrared gas analyzer, and method for manufacturing the joint.

Abstract

To provide a junction with high airtightness in which there is no crack in a glass member and a metal member, the junction between dissimilar materials difficult to absorb corrosive gas such sulfur dioxide gas.SOLUTION: Provided are a junction, a detector for an infrared gas analyzer comprising the junction, an infrared gas analyzer, and a method for manufacturing the junction, the junction comprising: a glass member 1 comprising a metal lamination part including a first layer 2 and a second layer 3; a metal member 9 comprising a metal lamination part including a first layer 8 and a second layer 7; and a solder bonding layer 5 provided between the metal lamination part of the glass member and the metal lamination part of the metal member, where the first layer 2, 8 is a Cr layer or a Ti layer in contact with the glass member 1 or the metal member 9, the second layer 3, 7 is a Pt layer or a Ni layer in contact with the first layer 2, and the solder bonding layer 5 is a bonding layer in which a solder material containing Sn is melted.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a joint, a detector for an infrared gas analyzer comprising the same, an infrared gas analyzer, and a method for manufacturing the joint. [Background Art]

[0002] Conventionally, gas analyzers have been widely used for the purposes of optimal operation of equipment, energy saving, and environmental measurement such as air pollution. An absorption-type infrared gas analyzer performs qualitative and quantitative analysis of a sample gas based on the amount of infrared absorption by a measurement component gas contained in the sample gas. This method is generally widely used as a gas analyzer in various fields because of its good selectivity and high measurement sensitivity.

[0003] An infrared gas analyzer comprises an infrared transmission window, a main body block that defines a gas chamber together with the infrared transmission window, and a sensor unit accommodated in an accommodation space communicating with the gas chamber formed in the main body block, the sensor unit detecting the concentration of a gas to be measured. These members have been assembled using an adhesive. In detection, the gas to be measured is sealed in the gas chamber inside the main body block. At this time, it has been a problem that the sealed gas to be measured causes a chemical reaction with the adhesive, leading to a decrease in detection sensitivity.

[0004] There is known a detector for an infrared gas analyzer in which an infrared transmission window, a main body block, and a sensor unit, which are members constituting the infrared gas analyzer, are bonded with an acidic adhesive containing an acid anhydride curing agent and a silica filler (see, for example, Patent Document 1). The invention according to Patent Document 1 discloses that even when sulfur dioxide (SO2) gas, which is a corrosive gas, is sealed inside the gas chamber, the adhesive is less likely to cause a chemical reaction with the SO2 gas, enabling stable detection of the concentration of the gas to be measured over a long period of time.

[0005] An infrared detector is known in which an infrared transmission window is formed by forming a eutectic alloy layer of aluminum and silicon on a silicon substrate, and having a metallized portion on the surface of the eutectic alloy layer in which chromium, copper, and gold are laminated in that order, and an infrared transmission portion in which a filter layer is formed on the unmetallized portion of the silicon substrate, and this infrared transmission window is sealed to a mounting container using solder with a lower melting point than the filter layer forming material (see, for example, Patent Document 2). The invention described in Patent Document 2 discloses that the infrared transmission window can be directly soldered to the metallized portion and sealed to the container with high airtightness and reliability.

[0006] In the infrared transmission window mounting structure of an infrared analyzer, a technique is known for fixing the infrared transmission window to the main body using a bonding material with a melting point of 200 to 500 degrees Celsius, such as solder or low-melting-point glass (see, for example, Patent Document 3). The invention described in Patent Document 3 discloses that it is possible to fix the infrared transmission window to the main body without causing cracks in the infrared transmission window or affecting the physical properties of the infrared transmission window. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2021-143899 [Patent Document 2] Japanese Patent Application Publication No. 6-147971 [Patent Document 3] Japanese Patent Application Publication No. 6-82371 [Overview of the project] [Problems that the invention aims to solve]

[0008] The technology disclosed in Patent Document 2 has problems such as the process becoming complicated, requiring special treatment of the substrate. Furthermore, the technology disclosed in Patent Document 3 has problems such as the binder used for the low-melting-point glass, or the low-melting-point glass itself, reacting with the gas sealed inside the gas chamber, and the formation of voids or other air gaps inside due to the desorption of the binder during heating, which adversely affects airtightness.

[0009] The technology disclosed in Patent Document 1 demonstrates that a decrease in the concentration of the enclosed gas can be suppressed by using an adhesive of a specific composition, thereby suppressing the decrease in absorbance over time within the gas chamber. However, a technology is needed to further suppress the adsorption of SO2 gas at the joint. [Means for solving the problem]

[0010] As a result of diligent research, the inventors conceived of joining the glass component constituting the infrared-transmitting window and the metal component constituting the main body using solder material via a metal laminate formed on their surfaces, thereby completing the present invention.

[0011] In other words, according to one embodiment of the present invention, the present invention relates to a joint comprising: a glass member having a metal laminate including a first layer and a second layer; a metal member having a metal laminate including a first layer and a second layer; and a solder joint layer provided between the metal laminate of the glass member and the metal laminate of the metal member, wherein the first layer is a Cr layer or Ti layer in contact with the glass member or the metal member; the second layer is a Pt layer or Ni layer in contact with the first layer; and the solder joint layer is a joint layer in which solder material containing Sn is molten.

[0012] In the joint, the metal laminate portion provided on the glass member and / or the metal laminate portion provided on the metal member preferably comprises a third layer in contact with the second layer, and the third layer is preferably an Au layer or a Cu layer.

[0013] In the aforementioned joint, it is preferable that the glass member is made of CaF2.

[0014] In the aforementioned joint, it is preferable that the metal member is made of aluminum.

[0015] In the aforementioned joint, it is preferable that the solder material containing Sn is a solder material consisting of Sn and unavoidable impurities.

[0016] In the aforementioned joint, it is preferable that the glass member is a flat infrared-transmitting window having the metal laminated portion around its periphery, the metal member is a housing component having an opening and the metal laminated portion around the opening, and the solder joint layer is a joint layer formed by melting sheet solder in a shape that conforms to the metal laminated portion on the glass member and the metal laminated portion on the metal member.

[0017] In another aspect, the present invention relates to a mounting structure for an infrared-transmitting window, the mounting structure for an infrared-transmitting window comprising the aforementioned joint.

[0018] In another aspect, the present invention relates to an infrared gas analyzer detector capable of detecting the concentration of a target gas containing sulfur dioxide gas, wherein the components of the infrared gas analyzer detector include an infrared transmission window that transmits infrared rays, a housing that partitions a gas chamber together with the infrared transmission window, and a sensor unit housed in a containment space formed within the housing that leads to the gas chamber and detects the concentration of the target gas, and the joint between the infrared transmission window and the housing has the aforementioned joint.

[0019] In another aspect, the present invention relates to an infrared gas analyzer comprising: a measuring cell; a light source unit disposed at one end of the measuring cell for irradiating the measuring cell with infrared light; and a detector disposed at the other end of the measuring cell for detecting the intensity of the infrared light that has passed through the measuring cell, wherein the detector is the aforementioned infrared gas analyzer detector.

[0020] According to another aspect, the present invention relates to a method for producing a joint between a glass member and a metal member, comprising the method comprises: forming a metal laminated portion including a first layer and a second layer on a glass member; forming a metal laminated portion including a first layer and a second layer on a metal member; laminating the glass member, a plate-shaped solder material, and the metal member in such a manner that the metal laminated portion of the glass member is in contact with one main surface of the plate-shaped solder material, and the other main surface of the solder material is in contact with the metal laminated portion of the metal member, and heating and melting the solder material, wherein the first layer is a Cr layer or a Ti layer in contact with the glass member or the metal member, the second layer is a Pt layer or a Ni layer in contact with the first layer, and the solder material is a Sn-containing solder material.

[0021] In the above production method, it is preferable that the metal laminated portion formed on the glass member and / or the metal laminated portion formed on the metal member comprises a third layer in contact with the second layer, and the third layer is an Au layer or a Cu layer. Effects of the Invention

[0022] According to the present invention, a highly airtight joint can be obtained without cracks in the glass member or the metal member. Further, the detector for an infrared gas analyzer and the infrared gas analyzer comprising the joint provided with the joint can provide high-precision gas analysis due to the low reactivity of the materials constituting the joint with the internal gas. Brief Description of the Drawings

[0023] [Figure 1] Fig. 1 is a schematic cross-sectional view showing the cross-sectional structure of a joint according to a first embodiment of the present invention. [Figure 2] Fig. 2 is a schematic cross-sectional view illustrating a detector for an infrared gas analyzer according to a second embodiment of the present invention and an infrared gas analyzer comprising the same. [Figure 3] Fig. 3 is a schematic view illustrating a mounting structure of an infrared transmission window according to a second embodiment of the present invention.

[0024] Embodiments of the present invention will be described below with reference to the drawings. However, the present invention is not limited to the embodiments described below.

[0025] [First Embodiment: Joint] According to a first embodiment of the present invention, the joint comprises a glass member having a metal laminate including a first layer and a second layer, a metal member having a metal laminate including a first layer and a second layer, and a solder joint layer provided between the metal laminate of the glass member and the metal laminate of the metal member.

[0026] In this embodiment, the glass member may be an oxide glass such as silicate glass, or a non-oxide glass such as halide glass or chalcogenide glass. If the glass member is an infrared-transmitting member used in optical instruments, for example, the glass member may be not only a fluoride glass such as CaF2, but also other infrared-transmitting materials.

[0027] In this embodiment, the metal member may be any metal, and may be a single metal or an alloy. If the metal member is a metal that can be used as a housing in various devices, the metal member may be aluminum (Al), stainless steel, copper (Cu), etc., but is not limited to these.

[0028] Both the glass member and the metal member have a metal laminated portion on the bonding surface, which is the surface that contacts the solder bonding layer. The metal laminated portion includes at least two metal layers, preferably three metal layers.

[0029] The metal laminate formed on the bonding surface of the glass member includes, in order from the side closest to the glass member, a first layer and a second layer, and optionally includes a third layer. The metal laminate can be continuously provided over the entire surface of the bonding surface between the glass member and the metal member.

[0030] The first layer is a Cr or Ti layer in contact with the glass member. The first layer functions as a base layer, ensuring adhesion between the glass member, the metal laminate, and the solder joint layer joined thereto. The thickness of the first layer is preferably about 0.05 to 0.2 μm, and more preferably about 0.1 to 0.15 μm. If the thickness exceeds the above range, excessive residual stress may occur in the deposited film, causing delamination. If it is below the above range, the deposited film may become non-uniform. The lower limit of the thickness of the first layer is preferably increased if the surface roughness of the metal member is rough.

[0031] The second layer is a Pt or Ni layer in contact with the first layer. The second layer is provided to ensure adhesion between the first layer and the solder joint layer or an optional third layer joined thereto, as well as to ensure good wetting to the solder material forming the solder joint layer and to prevent diffusion and disappearance during soldering heat input. The thickness of the second layer is preferably about 0.1 to 1.0 μm, and more preferably about 0.2 to 0.7 μm. If the thickness exceeds the above range, excessive residual stress may be generated in the deposited film, causing delamination. If the thickness is below the above range, the second layer may diffuse and disappear due to heat input during joining.

[0032] The third layer is an optional layer, and if present, it is either an Au layer or a Cu layer. The third layer functions as an upper layer of the metal laminate and is provided to ensure sufficient wettability with the solder material that forms the solder joint layer. The thickness of the third layer is preferably about 0.01 to 1.0 μm, and if the entire surface is covered with the third layer, a thinner layer is more economically desirable. If the thickness exceeds the above range, it may be economically costly, and if it is below the above range, undeposited areas may be formed, and the oxide film of the second layer may form in those areas, potentially causing bonding failure. The third layer is provided to improve the bonding with the solder material that constitutes the solder joint layer, which will be described later, and in some cases, it may diffuse and disappear due to the heat of soldering. Therefore, even if the third layer is formed during manufacturing, it is not guaranteed that the third layer will exist in a clear layer form at the resulting joint. For example, when the third layer is analyzed by SEM (scanning electron microscope)-EDX (energy-dispersive X-ray spectroscopy), the elements that make up the third layer, such as Au and Cu, may be localized or scattered between the second layer and the solder joint layer.

[0033] These metal layers are preferably pure metals rather than alloys. The first, second, and third layers may all be vapor-deposited films produced by a vapor deposition method, and may be chemically vapor-deposited films or physically vapor-deposited films.

[0034] Next, the metal laminate formed on the joining surface of the metal member includes a first layer and a second layer, in order from the side closest to the metal member, and optionally includes a third layer. The metal laminate can be provided continuously across the entire area of ​​the joining surface between the metal member and the glass member. The arrangement, material, and thickness of each layer can be independently selected from the same options as those for the metal laminate provided on the glass member. Therefore, as long as the conditions for each layer constituting the metal laminate described above are met, the first layer of the glass member and the first layer of the metal member may be of the same or different metal type, and may have the same or different thicknesses. The second layer of the glass member and the second layer of the metal member may be of the same or different metal type, and may have the same or different thicknesses. The third layer of the glass member and the third layer of the metal member may be of the same or different metal type, and may have the same or different thicknesses, and one may be present while the other is absent, or both may be present or neither may be present.

[0035] The solder joint layer is a layer obtained after melting and cooling solder material, where one main surface is in contact with the metal laminate of the glass member and the other main surface is in contact with the metal laminate of the metal member. This joins the glass member and the metal member. The solder material forming the solder joint layer may be a metal or alloy containing Sn and potentially containing unavoidable impurities. Unavoidable impurities in the solder material mainly refer to Cu, Ni, Zn, Fe, Al, As, Cd, Au, In, P, Pb, etc. The upper limit of the content of each element treated as an unavoidable impurity varies depending on the main component of the solder material and is defined by international standards. Preferably, the solder material is lead-free solder that may contain only Pb as an unavoidable impurity. The solder material may be substantially composed of Sn and not contain other metals. Alternatively, in addition to Sn, the solder material may contain additional metals that have low reactivity with the atmospheric gas in which the equipment or other device equipped with the joint is used. Additional metals may include, but are not limited to, Au, Al, and Cu. The solder material before melting is preferably a sheet solder processed to conform to the shape of the joint.

[0036] It is preferable that the solder joint layer is formed such that its thickness after joining is, for example, about 10 to 300 μm.

[0037] Figure 1 is a conceptual cross-sectional view showing the cross-sectional structure of the joint according to this embodiment. Referring to Figure 1, a first layer 2 of the metal laminate is formed in contact with the glass member 1, a second layer 3 of the metal laminate is formed in contact with the first layer 2, and a third layer 4 of the metal laminate is formed in contact with the second layer 3. The third layer 4 of the metal laminate is in contact with and joined to the solder joint layer 5. Similarly, a first layer 8 of the metal laminate is formed in contact with the metal member 9, a second layer 7 of the metal laminate is formed in contact with the first layer 8, and a third layer 6 of the metal laminate is formed in contact with the second layer 7. The third layer 6 of the metal laminate is in contact with and joined to the solder joint layer 5. In one embodiment, the glass member may be CaF2, the first layer 2 of the metal laminate provided on the glass member 1 may be a Cr vapor-deposited film, the second layer 3 may be a Pt vapor-deposited film, and the third layer 4 may be a Cu vapor-deposited film. The solder material constituting the solder joint layer 5 may be made of pure Sn. The metal member 9 may be made of aluminum, and the first layer 8 of the metal laminate provided on the metal member 9 may be a Cr vapor-deposited film, the second layer 7 may be a Pt vapor-deposited film, and the third layer 6 may be a Cu vapor-deposited film.

[0038] Next, a method for manufacturing a joint according to the first embodiment will be described. The method for manufacturing a joint according to the first embodiment includes the following: (1) A step of forming a metal laminate portion including a first layer and a second layer on a glass member, (2) A step of forming a metal laminated portion including a first layer and a second layer on a metal member, (3) Laminating the glass member, the plate-shaped solder material, and the metal member in such a manner that the metal laminate portion of the glass member is in contact with one main surface of the plate-shaped solder material, and the other main surface of the solder material is in contact with the metal laminate portion of the metal member, and then heating and melting the solder material.

[0039] In step (1), a metal laminate is formed on the glass member. The metal laminate can be formed by a conventional vapor deposition method using a vapor deposition apparatus to form a vapor-deposited film on the glass member, and the vapor deposition atmosphere is set to 10 to prevent oxidation of the vapor-deposited layer. -3 A vacuum atmosphere of approximately Pa or less can be maintained. Furthermore, it is preferable that the first layer, which serves as the base layer, the second layer, which serves as the barrier layer, and the third layer, which serves as the top layer, are not exposed to the atmosphere during the deposition process, but are continuously deposited while maintaining a vacuum atmosphere.

[0040] In step (2), a vapor-deposited film can be formed on the metal component under the same conditions as in step (1).

[0041] In step (3), the glass member with the metal laminated portion and the metal member are joined by soldering. The solder material used can be in the form of a plate, wire, paste, etc., but from the viewpoint of ensuring airtightness, it is preferable to use a plate-shaped solder material. When soldering, it is preferable to process the plate-shaped solder material into a shape that conforms to the shape of the joint by punching or the like. In addition, it is preferable to clean and degrease the solder material with ethanol or acetone before joining.

[0042] The solder material, processed into a predetermined shape, is sandwiched between the glass member and the metal member such that the second layer of the metal laminate, or the third layer if present, contacts the solder material. Then, if necessary, measures such as ensuring good heat conduction and suppressing tilting of the joint can be taken using a joining jig. The soldering atmosphere is a formic acid environment, which is a reducing environment, or 10°C, in order to prevent surface oxidation of the solder material and the metal laminate. -3 It is preferable to use a vacuum atmosphere of Pa or less. Regarding the bonding temperature, the heating rate and holding temperature can be determined so that the entire bonding area reaches a temperature above the solidus line of the solder material.

[0043] The joint manufactured by this embodiment has the advantages of being less prone to cracking or defects in glass or metal components during joining, having high airtightness after joining, and exhibiting almost no gas adsorption to the joint. More specifically, it has the advantage of hardly reacting with SO2 gas, a corrosive gas that can be adsorbed by epoxy resin adhesives used in conventional technology, and also not reacting with other reactive gases such as CO2, CO, NO2, CH4, etc.

[0044] The joint according to this embodiment can be used for joining dissimilar materials, such as glass and metal members, and is particularly suitable for joining dissimilar materials in optical instruments. Depending on the type of compound forming the glass, the glass member can selectively transmit light of different wavelengths, such as ultraviolet, infrared, and visible light. In optical instruments where these glass members are joined to other members, such as housings, as light-transmitting windows, the joint according to this embodiment is preferably used as a joining structure for light-transmitting windows. Regardless of the type of glass member, it is usually possible to form a metal laminate on it by methods such as vapor deposition, and the joint can be manufactured using any glass member.

[0045] [Second Embodiment: Infrared Gas Analyzer, Detector for Infrared Gas Analyzer, and Mounting Structure for Infrared Transmission Window] According to a second embodiment, the present invention relates to an infrared gas analyzer, a detector for an infrared gas analyzer, and a mounting structure for an infrared transmission window. The infrared gas analyzer, the detector for an infrared gas analyzer, and the mounting structure for an infrared transmission window all have a joint between a glass member and a metal member according to the first embodiment, and are part of the components that make up the infrared gas analyzer. Therefore, in this embodiment, the infrared gas analyzer will be described first. The infrared gas analyzer according to this embodiment is an infrared gas analyzer that measures the concentration of a component gas by utilizing the gas pressure fluctuation associated with the infrared spectral absorption of an infrared-active component gas to be measured.

[0046] Figure 2 is a cross-sectional view of an infrared gas analyzer. The infrared gas analyzer consists of a light source unit 22, an optical chopper 26, a sample cell 29, and an infrared gas analyzer detector 35.

[0047] The light source unit 22 consists of a light source chamber 23, an infrared light source 24, and an infrared transmission window 25, and is located on one end of the sample cell 29. The infrared light source 24 is located inside the light source chamber 23, and is powered by a connected power supply, generating heat and emitting infrared radiation corresponding to its temperature. The infrared radiation passes through the infrared transmission window 25, which is positioned in the direction of infrared radiation, through the optical chopper 26, and is irradiated into the interior of the sample cell 29.

[0048] The optical chopper 26 consists of a rotating disk 27 and a motor 28. The rotating disk 27 is driven to rotate by the motor 28 and is positioned to rotate between the light source unit 22 and the sample cell 29. The rotating disk 27 also has an opening or notch that allows infrared rays to pass through. When the rotating disk 27 rotates, the opening or notch turns the infrared rays emitted from the light source unit 22 on and off at a predetermined interval, thereby intermittently irradiating the sample cell 29 with infrared rays.

[0049] The sample cell 29 consists of a cell body 30, sample gas inlets and outlets 31 and 32, and infrared-transmitting windows 33 and 34. The cell body 30 is made of a corrosion-resistant metal material such as stainless steel and is cylindrical in shape. The infrared-transmitting windows 33 and 34 are made of an infrared-transmitting material and are sealed and fixed to both ends of the cell body 30. Sample gas is introduced from one of the sample gas inlets and outlets 31 and 32 and discharged from the other. An infrared gas analyzer detector 35 is located at the other end of the sample cell 29 (opposite the light source 22).

[0050] The infrared gas analyzer detector 35 comprises, as its components, at least a main body block 9a, infrared transmission windows 1a, 1b, and 1c, and a sensor unit (mass flow sensor) 44. The structure of the infrared gas analyzer detector 35 will be described in detail below.

[0051] The infrared gas analyzer detector 35 is provided with a first gas chamber 37 and a second gas chamber 38, arranged in parallel on the optical path of infrared rays that have passed through the sample cell 29, starting from the front (light source 22 side). The first gas chamber 37 and the second gas chamber 38 are separated by a main body block 9a, which is a housing made of aluminum, for example, and infrared-transmitting windows 1, 40, and 41. The infrared-transmitting windows 1a, 1b, and 1c are made of an infrared-transmitting material such as CaF2, for example, and transmit infrared rays. The infrared-transmitting window 1a on the front (light source side), the infrared-transmitting window 1b between the first gas chamber 37 and the second gas chamber 38, and the infrared-transmitting window 1c on the rear (side from which infrared rays are emitted from the second gas chamber 38) are arranged in parallel.

[0052] The number of gas chambers 37 and 38 is arbitrary and may be three or more. Furthermore, an infrared reflector that reflects infrared radiation can be placed in the rearmost gas chamber.

[0053] The main body block 9a houses the sensor unit 44 in a sensor unit housing space located to the side of the first gas chamber 37. Within the main body block 9a, there is also a first passage 42 connecting the sensor unit housing space to the first gas chamber 37, and a second passage 43 connecting the sensor unit housing space to the second gas chamber 38.

[0054] The sensor unit 44 is provided with an internal sensor passage that communicates with the first passage 42. A hermetic terminal connecting to the sensor unit 44 is inserted into the main body block from the outer surface, and a lead pin made of conductive material is provided on the hermetic terminal to output the signal detected by the sensor unit 44 to the outside (not shown).

[0055] In this embodiment, infrared light is emitted from the light source unit 22, passes through the sample cell 29, and is incident on the infrared gas analyzer detector 35. The infrared light incident on the sample cell 29 is partially absorbed according to the concentration of the gas component to be measured in the sample gas, and the remaining infrared light is incident on the infrared gas analyzer detector 35.

[0056] The first gas chamber 37 and the second gas chamber 38 of the infrared gas analyzer detector 35 are sealed with the gas component to be measured. Most of the incident infrared radiation is absorbed in the first gas chamber 37, and the remainder is absorbed in the second gas chamber 38. At this time, volume expansion proportional to the amount of infrared radiation absorbed occurs, creating a pressure difference between the first gas chamber 37 and the second gas chamber 38. This generates a minute gas flow inside the first passage 42, the sensor unit housing space, and the second passage 43 that connect the gas chambers. The sensor unit 44 detects the change in pressure or flow rate due to this gas flow as a change in resistance and converts it into an electrical signal to measure the gas concentration.

[0057] In the infrared gas analyzer detector 35, the joint A between the infrared transmission window 1a and the main body block 9a is joined by the joining method described in the first embodiment, and constitutes the joint according to the first embodiment.

[0058] Figure 3 is a view of the infrared transmission window 1a of the infrared gas analyzer detector 35, as seen from the sample cell 29 side. In other words, it is a plan view of the infrared transmission window 1a and the main body block 9a from a direction perpendicular to the joint surface at joint A. The infrared transmission window 1a may be disc-shaped. The main body block 9a has a circular opening with a smaller diameter than the infrared transmission window 1a. Annular metal laminated sections 2, 3, and 4 are provided on the periphery of the infrared transmission window 1a, and annular metal laminated sections 6, 7, and 8 are also provided on the edge along the opening of the main body block 9a. The annular metal laminated sections 2, 3, and 4 are formed to fit the metal laminated sections 6, 7, and 8 when the infrared transmission window 1a is superimposed on the main body block 9a. The infrared transmission window 1a and the main body block 9a are joined by a solder joint layer 5, which is formed by melting solder material processed as annular members with substantially the same shape as these annular metal laminated sections, thereby forming the joint. The joint in the infrared gas analyzer detector 35 can also be considered as the mounting structure for the infrared transmission window 1a to the main body block 9a, which is the housing. According to the mounting structure for the infrared transmission window 1a in this embodiment, the infrared transmission window 1 can be attached to the housing in a relatively simple manner, in an airtight manner, and in a manner that does not pose a risk of adsorption of corrosive gases, etc.

[0059] Figure 3 illustrates the infrared-transmitting window 1a, the main body block 9a, and the annular metal laminated section for the purpose of explaining the invention. The relative size of the infrared-transmitting window 1a and the opening, the position of the annular metal laminated section, and the width of the ring are not intended to be precise dimensions and do not limit the present invention.

[0060] Similarly, the joints between the infrared-transmitting windows 1b and 1c and the main body block 9a are joined in the manner described above, constituting the joint according to the first embodiment.

[0061] According to a second embodiment of the present invention, a detector for an infrared gas analyzer having the joint portion of the first embodiment and an infrared gas analyzer can be provided, and the problem of SO2 gas adsorption can be solved when using the analyzer. This enables highly accurate analysis. [Examples]

[0062] The present invention will be described in more detail below with reference to embodiments of the present invention. However, the present invention is not limited to the scope of the following embodiments. An infrared gas analyzer according to a second embodiment, which is equipped with a joint according to the first embodiment, and an infrared gas analyzer equipped with a joint manufactured using an adhesive according to the prior art were manufactured and their characteristics were confirmed.

[0063] [Examples] The main body block was constructed using an aluminum (A6063) plate with a thickness of 10 mm and a 22 mm diameter opening. The infrared-transmitting window was made of a 1 mm thick, 21.5 mm diameter disc-shaped CaF2. A metal laminate consisting of a vapor-deposited film was formed around the infrared-transmitting window and around the opening in the aluminum plate. The first layer in contact with the infrared-transmitting window and the aluminum plate was a 0.1 μm Ti vapor-deposited film, the second layer in contact with the first layer was a 1.0 μm Pt vapor-deposited film, and the third layer in contact with the second layer was a 0.3 μm Au vapor-deposited film. The vapor deposition was carried out in a formic acid environment. For the formation of the solder joint layer, a solder material consisting of 99.9 mass% Sn with a thickness of 300 μm was used, and the soldering temperature profile was a bonding temperature of 260°C and a holding time of 7 min. No cracks were found in the CaF2 or aluminum plate after bonding, and no bonding defects were observed. The other components of the infrared gas analyzer were assembled using the same methods as in conventional technology.

[0064] The infrared gas analyzer obtained as described above was filled with an internal gas containing SO2 gas, and its sealing stability was evaluated. The sealing stability of the internal gas was evaluated by measuring the SO2 gas concentration using FT-IR (Fourier Transform Infrared Spectroscopy) once a day for 30 days after filling. The measurement results showed that the variation in the mass of SO2 gas in the internal gas after 31 days from filling was within approximately ±1%, indicating stability. From these results, it can be seen that the airtightness of the joint was maintained, and that the internal gas did not adsorb or undergo chemical reactions with the joint material.

[0065] [Comparative Example] The joint was manufactured in the same manner as in the example, except that no metal laminates were provided in the housing and infrared transmission window, no solder was used, and the housing and infrared transmission window were bonded together with adhesive. An epoxy adhesive was used as the adhesive. After applying the adhesive to the housing with a dispenser, the infrared transmission window was placed on the adhesive under a predetermined load, and the housing and infrared transmission window were bonded together by drying at 150°C for 4 hours. No cracks were found in the CaF2 and aluminum plates after bonding, and no defects in the joint were observed. Other components of the infrared gas analyzer were assembled using the same method as in the prior art.

[0066] The infrared gas analyzers of the examples and comparative examples obtained as described above were filled with internal gas, and the sealing stability was evaluated using the same method as in the examples. The measurement results showed that the internal gas decreased over time, and the change in FTIR absorbance after 31 days from sealing was a maximum of approximately 7%. This is thought to be due to the adsorption of SO2 gas onto the adhesive.

[0067] Table 1 shows the bonding / adhesion conditions and FTIR absorbance change (%) for the examples and comparative examples. In the table, "-" means that the configuration does not exist. Examples 1(1) to (3) show the results of three measurements performed under the same conditions. Comparative Examples 1(1) to (5) show the results of five measurements performed under the same conditions. The bonding section according to the present invention significantly reduced the absorbance change compared to the bonding section of the comparative examples. This enabled more accurate analysis using an infrared gas analyzer.

[0068] [Table 1] [Explanation of Symbols]

[0069] 1. Glass component; 2. First layer; 3. Second layer; 4. Third layer; 5. Solder joint layer. 6 Third layer, 7 Second layer, 8 First layer, 9 Metal component 1a, 1b, 1c Infrared-transmitting window, 9a Housing

Claims

1. A detector for an infrared gas analyzer capable of detecting the concentration of a target gas containing sulfur dioxide gas, The detector components for the infrared gas analyzer include an infrared transmission window that transmits infrared light, a housing that partitions a gas chamber together with the infrared transmission window, and a sensor unit housed in a containment space formed within the housing that leads to the gas chamber, and which detects the concentration of the gas to be measured. The infrared-transmitting window is a flat glass member having a metal laminated portion surrounding it, which includes a first layer and a second layer. The housing is made of a metal member having an opening and a metal laminate portion including a first layer and a second layer surrounding the opening. The glass member and the metal laminated portion of the metal member are provided with a solder joint layer in which a sheet of solder shaped to fit the metal laminated portion on the glass member and the metal laminated portion on the metal member is molten, thereby joining the infrared-transmitting window and the housing. The first layer is a Cr layer or Ti layer in contact with the glass member or the metal member, The second layer is a Pt layer or Ni layer in contact with the first layer. A detector for an infrared gas analyzer, wherein the solder joint layer is a joint layer formed by melting a solder material consisting of Sn and unavoidable impurities.

2. The detector for an infrared gas analyzer according to claim 1, wherein the metal laminate portion provided on the glass member and / or the metal laminate portion provided on the metal member comprises a third layer in contact with the second layer, and the third layer is an Au layer or a Cu layer.

3. The glass member is CaF ２ A detector for an infrared gas analyzer according to claim 1, comprising a component made of the above.

4. The detector for an infrared gas analyzer according to claim 1, wherein the metal member is made of aluminum.

5. Measurement cell and A light source unit is positioned at one end of the measurement cell and irradiates the measurement cell with infrared light. A detector positioned on the other end of the measurement cell, which detects the intensity of infrared light that has passed through the measurement cell. An infrared gas analyzer equipped with, An infrared gas analyzer wherein the detector is the detector for the infrared gas analyzer described in claim 1.

6. A method for manufacturing the joint between a glass member and a metal member in the infrared gas analyzer detector according to Claim 1, A process of forming a metal laminate portion including a first layer and a second layer on a glass member, A process of forming a metal laminated portion including a first layer and a second layer on a metal member, The glass member, the plate-shaped solder material, and the metal member are laminated such that one main surface of the plate-shaped solder material is in contact with the metal laminate portion of the glass member, and the other main surface of the solder material is in contact with the metal laminate portion of the metal member, and the solder material is heated and melted. Includes, The first layer is a Cr layer or Ti layer in contact with a glass member or a metal member. The second layer is a Pt layer or Ni layer in contact with the first layer. A method for manufacturing the aforementioned solder material, wherein the solder material contains Sn.

7. The manufacturing method according to claim 6, wherein the metal laminate formed on the glass member and / or the metal laminate formed on the metal member comprises a third layer in contact with the second layer, and the third layer is an Au layer or a Cu layer.

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