Crushing-resistant glass part for sensor comprising glass part on housing

Abstract

The invention relates to a crush resistant glass part for a sensor comprising a glass part on a housing. A method for producing a crush-resistant glass part (1) for an analyte-sensitive sensor, comprising:-providing at least one glass part (1) of the sensor, consisting of a sodium-containing and / or lithium-containing glass, preferably a sodium silicate and / or lithium silicate glass; -bringing the at least one glass part into contact with a melt or solution containing potassium nitrate, wherein the glass part comprises an inner shaft tube (2) and an outer shaft tube (3) surrounding the inner shaft tube and connected thereto in a materially locked manner.

Description

Technical Field

[0001] The present invention relates to a sensor-containing anti-shattering glass component, a sensor of the anti-shattering glass component, and a method for producing the anti-shattering glass component. Background Art

[0002] Determining the concentration of an analyte in a measurement medium plays an important role in many industrial applications, such as in chemical or pharmaceutical engineering, food technology, biotechnology, but also in non-industrial analytical applications, such as in environmental measurement technology. To determine the ion concentration, sensors with sensor elements having analyte-sensitive components are often used in laboratories and industrial process plants. For example, an analyte-sensitive membrane can be used as the analyte-sensitive component. For example, it is known that the glass membrane of a pH glass electrode is sensitive to the concentration or activity of H + or H3O + ions.

[0003] Electrochemical sensors with anti-shattering glass components - preferably glass shaft components - are very popular because glass has excellent corrosion resistance to acids and bases.

[0004] A measuring probe with a glass electrode for pH and redox measurements is described in 20 2006 017 215 U1.

[0005] However, the disadvantage of glass electrodes is that they are prone to cracking and / or breaking. These are the types of problems that can occur in pH combination electrodes, which have a certain probability of causing incorrect measurements or malfunctions of the combination electrodes. For example, if an ion-sensitive membrane glass is attached to a glass component containing a glass shaft, mechanical stress occurs during the production of the glass assembly, where the glass components to be joined are heated, melted, and deformed using a gas burner or other heat source. Summary of the Invention

[0006] Therefore, an object of the present invention is to provide a sensor that includes a glass component, the glass component including a glass shaft or a glass assembly, the glass assembly including an inner shaft and an outer shaft, the outer shaft being connected to the inner shaft at one end facing the medium and surrounding an inner tube, wherein the glass component is made of anti-shattering glass, which has better performance in anti-shattering than conventionally used sodium- and / or lithium-containing glass.

[0007] This object is achieved by a method for producing an anti-shattering glass component for an analyte-sensitive sensor, the method comprising:

[0008] - providing at least one glass component of the sensor, which is made of sodium- and / or lithium-containing glass, preferably made of sodium silicate and / or lithium silicate glass;

[0009] - contacting at least one glass component with a melt or solution containing potassium nitrate, wherein

[0010] the glass component

[0011] comprises an inner shaft tube and an outer shaft tube surrounding the inner shaft tube and connected to the inner shaft tube in a material-locked manner.

[0012] At the end of the inner shaft tube facing the medium during operation, it is preferably connected to the outer tube in a material-locked manner - for example, by welding. Thus, there is a cavity between the inner tube and the outer tube, and the cavity is designed to accommodate the reference electrolyte and the lead element of the reference half-cell.

[0013] In one embodiment, the inner tube is longer in the direction of the medium and thus protrudes more in the direction of the medium. In an alternative embodiment, the inner tube and the outer tube are of equal length and protrude to the same extent in the direction of the medium.

[0014] By exchanging sodium ions and lithium ions in the glass with potassium ions at a temperature of 200 - 400 °C, the low-period alkali metal ions - preferably sodium and / or lithium ions - in the layer near the surface are replaced by potassium ions. As a result, surface compressive stress is generated, which hinders crack growth and leads to high fracture strength.

[0015] According to the Vickers hardness test, the crack-resistant glass only shows cracks under a load exceeding 40 Newtons, while the conventional glass already shows cracks under a load of 5 Newtons. Generally, the scratch resistance of the crack-resistant glass is about two to three times that of the conventional glass. As is well known, in the Vickers hardness measurement, a rhombic pyramid-shaped indenter is pressed on the test sample with a predetermined test force P. The indenter leaves a square indentation on the surface of the test sample, and the diagonals d1, d2 are measured and averaged, where the average value is a measure of the hardness value to be obtained from the table. The Vickers hardness test method is defined in the standards ISO 6507 and ASTME384.

[0016] In one embodiment, the glass component further comprises at least one compound selected from the group consisting of compounds of alumina, boron oxide, barium oxide, strontium oxide, and iron oxide.

[0017] In one embodiment, contacting with the melt containing potassium nitrate includes immersing at least a part of the glass component in the melt containing potassium nitrate, wherein the temperature of the potassium nitrate melt is 200 - 400 °C.

[0018] In one embodiment, the glass component is completely immersed in the glass melt.

[0019] In one embodiment, the temperature of the potassium nitrate melt is 250 - 350 °C, preferably 320 °C to 330 °C, more preferably 300 °C.

[0020] In one embodiment, the glass component is immersed in a potassium nitrate melt for a period of from 2 minutes to 3 hours.

[0021] In one embodiment, contacting with a solution comprising potassium nitrate includes immersing in a solution comprising potassium nitrate or spraying or atomizing with a solution comprising potassium nitrate, followed by a drying step at 200 - 400 °C.

[0022] Preferably, this step takes one minute or less. More preferably, this step takes 10 - 30 seconds.

[0023] In one embodiment, the ion - sensitive sensor is an analyte - sensitive sensor, preferably a cation - sensitive or anion - sensitive sensor.

[0024] In one embodiment, the cation - sensitive sensor is a Na + 、K + sensor or a pH - sensitive or hydronium - ion - sensitive sensor.

[0025] In a preferred embodiment, the cation - sensitive sensor is a pH - sensitive or hydronium - ion - sensitive sensor.

[0026] The present invention also relates to a shatter - resistant glass component obtained by the method of the present invention or an embodiment thereof.

[0027] The present invention also relates to a method for a shatter - resistant glass component for producing a reference half - cell of an ion - sensitive glass sensor, the reference half - cell comprising an inner shaft tube and an outer shaft tube surrounding the inner shaft tube and connected to the inner shaft tube in a material - locking manner, the method comprising:

[0028] According to the method steps of the present invention or an embodiment thereof, followed by the following steps:

[0029] Cooling the glass component to room temperature

[0030] Cleaning the glass component, wherein the cleaning is preferably automated and preferably carried out using deionized water.

[0031] In a preferred embodiment, the inner shaft tube and the outer shaft tube are connected to each other in a material - locking manner at the end facing the medium, preferably by a fusion connection.

[0032] The present invention also relates to a method for a shatter - resistant glass component for producing an ion - sensitive glass sensor, comprising the method for producing a shatter - resistant glass component according to the present invention or an embodiment thereof, followed by the following steps:

[0033] Cooling the glass component to room temperature, the glass component comprising an inner shaft tube and an outer shaft tube surrounding the inner shaft tube and connected to the inner shaft tube in a material - locking manner,

[0034] A glass component is cleaned, where the cleaning is preferably automated and preferably carried out using deionized water.

[0035] The inner shaft tube (2) is enclosed by connecting the glass component to the pH-sensitive membrane glass in a material-locking manner or mechanically.

[0036] In an embodiment where the inner shaft tube is enclosed with a pH-sensitive glass membrane in a material-locking manner, a diaphragm is arranged in the outer tube. The diaphragm can be covered with a protective glass in a glass tube and can be exposed after treatment with a potassium nitrate melt or a potassium nitrate solution, for example, by grinding. In an alternative embodiment, the diaphragm can be inserted into the outer tube containing corresponding grooves after treatment with a potassium nitrate melt or a potassium nitrate solution.

[0037] The invention also relates to a method for producing a shatterproof glass assembly for an ion-sensitive glass sensor, including

[0038] A method for producing a shatterproof glass component for a reference half-cell according to the invention, followed by the following steps

[0039] Insert a cylindrical diaphragm into a groove in the inner shaft tube, where the diaphragm

[0040] has an O-ring on the outer surface for sealing with the inner shaft tube, and

[0041] has a cylindrical cavity inside, and

[0042] Insert the measuring half-cell containing the shaft tube and the pH-sensitive glass membrane into the cylindrical cavity.

[0043] The invention also relates to a shatterproof electrochemical sensor, including:

[0044] - A glass assembly obtainable by the method according to the invention,

[0045] - A measuring half-cell and a reference half-cell, each including leads and an electrolyte,

[0046] - An electronic unit electrically connected to the leads of the measuring half-cell and the leads of the reference half-cell.

[0047] Assuming technical feasibility, all the above modular systems and measuring systems can be combined with each other. Description of the Drawings

[0048] The invention is described in more detail below with reference to the embodiments shown in the drawings.

[0049] In the drawings:

[0050] Figure 1 : shows a glass assembly obtainable by the method according to the invention. Detailed implementation mode

[0051] Figure 1 Shown is a glass component (6) that can be obtained by the method according to the present invention, which includes a glass part (1) composed of an inner shaft tube (2) and an outer shaft tube (3), and the inner shaft tube (2) and the outer shaft tube (3) are made of anti-fragmentation glass. The outer shaft tube (3) has a diaphragm (4). The inner shaft tube (2) is connected to the ion-sensitive membrane glass (5) in a material-locking manner.

[0052] List of reference numerals

[0053] (1) Glass part

[0054] (2) Inner shaft tube

[0055] (3) Outer shaft tube

[0056] (4) Diaphragm

[0057] (5) Ion-sensitive membrane glass

[0058] (6) Glass component

Claims

1. A method for producing a shatter-resistant glass component (1) for an analyte-sensitive sensor, comprising: - providing at least one glass component (1) of the sensor, said at least one glass component consisting of a sodium- and / or lithium-containing glass, preferably a sodium silicate and / or lithium silicate glass; - contacting the at least one glass component with a melt or solution comprising potassium nitrate, wherein The glass component The invention comprises an inner shaft tube (2) and an outer shaft tube (3) surrounding the inner shaft tube and connected to the inner shaft tube in a material-locked manner.

2. The method according to claim 1, wherein: The glass member further comprises at least one compound selected from the group consisting of aluminum oxide, boron oxide, barium oxide, strontium oxide, and iron oxide.

3. The method according to claim 1 or 2, wherein: Contacting with a melt comprising potassium nitrate comprises immersing at least a portion of the glass component in the melt comprising potassium nitrate, wherein the temperature of the potassium nitrate melt is 200-400°C.

4. The method according to claim 3, wherein: The glass component (1) is completely immersed in the glass melt.

5. The method according to any one of claims 1 to 4, wherein: The temperature of the potassium nitrate melt is 250-350°C, preferably 320°C to 330°C, more preferably 300°C.

6. The method according to any one of claims 1 to 5, wherein: The glass component (1) is immersed in a potassium nitrate melt for a period of 2 minutes to 3 hours.

7. The method according to claim 1, wherein: Contacting with a solution comprising potassium nitrate comprises immersing in a solution comprising potassium nitrate or spraying or atomizing with said solution comprising potassium nitrate, wherein the contacting is followed by a drying step at 200-400°C.

8. The method according to any one of claims 1 to 7, wherein: The ion-sensitive sensor is an analyte-sensitive sensor, preferably a cation-sensitive or anion-sensitive sensor.

9. The method according to claim 8, wherein: The cation sensitive sensor is Na + , K + The sensor is either pH sensitive or hydronium ion sensitive.

10. The method according to claim 8 or 9, wherein: The cation sensitive sensor is a pH sensitive or hydronium ion sensitive sensor.

11. A shatter-resistant glass component for an analyte-sensitive sensor, said shatter-resistant glass component being obtainable by a method according to any one of claims 1 to 10.

12. A method for producing a shatter-resistant glass component (1) for a reference half-cell of an ion-sensitive glass sensor, the shatter-resistant glass component comprising an inner shaft tube (2) and an outer shaft tube (3) surrounding the inner shaft tube and connected to the inner shaft tube in a material-locking manner, the method comprising the method steps according to any one of claims 1 to 10, followed by the following steps: The glass component (1) is cooled to room temperature, Cleaning the glass component (1), wherein: The cleaning is preferably automated and is preferably performed using deionized water.

13. A method for producing a shatter-resistant glass component (6) for an ion-sensitive glass sensor, comprising the method steps according to any one of claims 1 to 10, followed by the following steps: The glass component (1) is cooled to room temperature, wherein the glass component comprises an inner shaft tube (2) and an outer shaft tube (3) surrounding the inner shaft tube (2) and connected to the inner shaft tube (2) in a material-locked manner, Cleaning the glass component (1), wherein: The cleaning is preferably automated and is preferably performed using deionized water, The inner shaft tube (2) is closed by connecting the glass component to the pH-sensitive membrane glass in a material-locked manner.

14. A method for producing a shatter-resistant glass component (6) for an ion-sensitive glass sensor, comprising: The method for producing a shatter-resistant glass component (1) of a reference half-cell according to claim 12, followed by the following steps: Insert a cylindrical diaphragm (4) into the groove in the inner shaft tube (2), wherein the diaphragm (4) - having an O-ring on the outer surface for sealing with the inner shaft tube (2), and - having a cylindrical cavity inside, and A measuring half-cell is inserted into the cylindrical cavity, the measuring half-cell comprising a shaft tube and a pH-sensitive glass membrane connected to the shaft tube in a material-locking manner.

15. A crush-resistant electrochemical sensor, comprising: - a glass component (6) obtainable by the method according to claim 13 or 14, - the measuring half-cell and the reference half-cell, including in each case the leads and the electrolyte, - an electronics unit electrically connected to the leads of the measuring half-cell and to the leads of the reference half-cell.

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