JPH02157647A - Production of ion selective glass electrode - Google Patents

Abstract

PURPOSE:To realize mass productivity, stability of quality, diversity of products and ease of packaging by forming an ion selective glass film layer and ion non-sensitive glass film layer respectively by using a patterning method and a sol-gel method on the surface of a substrate. CONSTITUTION:The central circular part of the substrate 1 is patterned and a prescribed metal alkoxide soln. is applied on one surface of the substrate 1 to stick the thin film of an ion non-sensitive sol; thereafter, the sol is gelatinized to form the ion non-sensitive gelatinized layer 3'. The part of the substrate 1 exclusive of the central circular part is then patterned and the prescribed metal alkoxide soln. is applied on the same one surface of the substrate 1 to stick the thin film of the ion responsive sol. The sol is gelatinized to form the ion responsive gelatinized layer 2'. The gelatinized layers 2', 3' are thereafter vitrified by heating and calcination to form the ion selective glass film layer 2 and the ion-sensitive glass film layer 3 on the surface of the substrate 1.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to a completely new method for manufacturing an ion-selective glass electrode used in an ion concentration measuring electrode for measuring the concentration of various ions such as p)(, pNa, etc.). This was done to develop a method.

(Prior Art) As a conventional method for manufacturing an ion-selective glass electrode, first, an ion-selective glass block whose composition is adjusted to have a predetermined selectivity for ions to be measured is manufactured, and then an electric In the case of an ion-selective glass electrode for a conventional type of ion concentration measurement electrode, in which the ion-selective glass electrode is bonded to the tip of a support tube made of insulating glass,
The above-mentioned ion-selective glass block is formed into an ultra-thin hemispherical shape using the balloon method, and is also a very compact sheet with excellent operability and maintainability, which was recently developed by the applicant. type ion concentration measuring electrode (for example, Japanese Patent Application No. 61-2853)
In the case of an ultra-thin flat plate-shaped ion-selective glass electrode used in Either the surface is cut out and then re-formed into a flat glass using a hot plate press, or the ion-selective glass block is sliced into an appropriate thickness using a mechanical cutting means, and the pre-formed flat glass is heated to a temperature above its softening temperature. Warm it up and stretch it out, or also
As already proposed by the applicant in No. 3802, after slicing the ion-selective glass block using a mechanical cutting means to produce a first glass sheet that is slightly thicker than the target thickness, A second glass sheet having a target thickness is manufactured by etching the surface of the first glass sheet, and then the second glass sheet is preheated to just before the melting temperature. Various methods are known, such as applying a predetermined amount of thermal energy to the surface of a glass sheet in a short period of time to melt only the surface of the second glass sheet and then solidifying it.

(Problems to be Solved by the Invention) However, in any case, in the conventional manufacturing method of the ion-selective glass electrode as described above, (a) mass production is basically difficult; Since it is necessary to manufacture an ion-selective glass block whose composition is adjusted according to the characteristics to be used, not only is the manufacturing cost very high, but also the quality is likely to vary. It is very difficult to keep up with the diversification of products. (a) There are some problems with the characteristics of the manufactured ion-selective glass electrode (for example, the amount of alkali ions eluted is too large for the sample amount and measurement level) Even if there are disadvantages such as lack of chemical stability or (a) Since only the single ion-selective glass electrode itself is manufactured, the ion-selective glass electrode must be remanufactured when it is assembled into a given ion concentration measurement electrode. , it is necessary to bond or adhere the ion-selective glass electrode to an ion-insensitive member, but since it is unavoidable that some alkali ions will elute from the ion-selective glass electrode, it must have sufficient strength and durability. Therefore, it is very difficult to bond or adhere them in such a way that they have the same ion-selective properties. Therefore, when configuring a so-called composite electrode for measuring the concentration of multiple types of ions, it is necessary to use multiple types of ion-selective glass electrodes. There were various problems such as the above-mentioned difficulty being extremely large due to the need to implement .

The present invention has been made in view of the above-mentioned conventional circumstances, and its purpose is to achieve excellent mass production, economical efficiency, stability of quality, diversity of products that can be manufactured, ease of implementation, etc. An object of the present invention is to provide a method for manufacturing an ion-selective glass electrode.

[Means to solve the problem]

In order to achieve the above object, the method for manufacturing an ion-selective glass electrode according to the present invention comprises: forming at least one ion-selective glass membrane layer at a predetermined location on the surface of a substrate made of an ion-responsive material; The feature is that an ion-insensitive glass membrane layer is formed on the surface other than the ion-selective glass membrane layer using a patterning method and a blue gel method using a metal alkoxide as a raw material, respectively. have

[Effect]

The effects achieved by employing such distinctive means are as follows.

That is, according to the method for producing an ion-selective glass electrode according to the present invention, a patterning method and a sol-gel method using a metal alkoxide as a raw material are used, as will become clearer from the description of the examples below. In this way, an ion-selective glass film layer is formed at a predetermined location on the surface of an ion-responsive substrate, and an ion-insensitive glass film layer is formed at a location other than the ion-selective glass film layer. By using a method similar to the manufacturing process, it is basically easy to reduce costs through mass production, and quality stability is ensured.Furthermore, the surface of the basic ion-responsive substrate is coated with the required ion-responsive substrate. Since we have adopted a method of forming an ion-selective glass membrane by the sol-gel method using metal alkoxide as a raw material that can exhibit the specified characteristics, we can create an ion-selective glass membrane according to the required characteristics. In addition, it is not necessary to go through the uneconomical process of manufacturing an ion-selective glass block with a composition adjusted accordingly. By forming an ion-selective glass membrane with specific characteristics, it is easy to modify it, so it is possible to sufficiently and quickly respond to the diversification of products. Rather than manufacturing the glass electrode itself and only that, it is possible to fabricate not only an ion-selective glass film layer (this can be done with multiple types) but also an ion-selective glass film layer on the surface of one ion-responsive substrate. Since we have adopted a method of also forming a sensitive glass membrane layer, even when configuring a composite electrode for measuring the concentration of multiple types of ions, the ion-selective glass electrode can be used to When mounted on a concentration measuring electrode, there are no difficulties in joining or gluing the ion-selective glass electrode and the ion-insensitive member, and there are no problems in terms of strength and durability, which were unavoidable in the past.

〔Example〕

Hereinafter, various embodiments of the present invention will be described based on the drawings (FIGS. 1 to 6).

FIG. 1 shows a flowchart representing the conceptual procedure of a method for manufacturing an ion-selective glass electrode according to the present invention.

As is clear from FIG. 1, first, one type of metal alkoxide (or multiple types of metal alkoxide a,
A metal alkoxide solution in which the components are homogenized by adding a predetermined solution (e.g. alcohol, water, etc.) to a mixed metal alkoxide (b, ..., X in a predetermined ratio) and stirring thoroughly. While generating (sol), patterning is performed by masking or the like as necessary on predetermined locations on the surface of a substrate made of a predetermined ion-responsive material.Next, the surface of the patterned substrate is A thin film of sol is attached to the surface of the substrate other than the masked portion by applying a sol or by dipping the patterned substrate in the sol. Subsequently, when the substrate to which the sol thin film is attached in this way is gradually air-dried or heated, the sol Ill undergoes chemical reactions such as hydrolysis and polycondensation, and eventually gels and dries. A gelled layer is formed on the surface of the substrate. Then, by repeating the above series of operations a predetermined number of times while changing the type, mixing ratio, or patterning of the metal alkoxide as necessary, at least one layer or multiple layers of the same component can be formed. Alternatively, the gel layer corresponding to the ion-selective glass membrane layer and the gel layer corresponding to the ion-insensitive glass membrane layer are placed at predetermined locations opposite to each other. to form. Thereafter, when the substrate with a predetermined gelled layer formed on its surface is heated and fired at a temperature considerably lower than the normal vitrification temperature (usually 1000°C or less), the gelled layer is vitrified, As a result, a predetermined ion-selective glass film layer and an ion-insensitive glass film layer are formed on the surface of the substrate.

FIG. 2 is a concrete explanatory diagram of the first embodiment. First, patterning (masking, not shown) is applied to the central circular part of the substrate 1, and then an ion-insensitive glass film layer is formed. A predetermined metal alkoxide solution for forming an ion-insensitive sol is applied to one side of the substrate l, a thin film of ion-insensitive sol is deposited, and then gelled to form an ion-insensitive gelled layer 3°. Then, a predetermined pattern for forming an ion-selective glass membrane layer is applied with patterning (masking: not shown) applied to areas other than the central circular portion of the substrate l (that is, the opposite to the above case). A metal alkoxide solution is applied to the same side of the substrate 1 to deposit a thin film of the ion-responsive sol, and then gelled to form the ion-responsive gel layer 2°, and then heated and baked to form the ion-responsive gel layer 2°. An ion-selective glass electrode with a single layer structure is formed by vitrifying the glass layers 2° and 3° to form an ion-selective glass film layer 2 and an ion-insensitive glass film layer 3 on the surface of the group [1]. It shows.

Further, FIG. 3 is an explanatory diagram of a specific second embodiment,
First, the substrate 1 is immersed in a predetermined metal alkoxide solution for forming an ion-selective glass film layer, without any patterning (masking = not shown) applied to the substrate 1. By repeating the operation of depositing a thin film of ion-responsive sol on the entire surface of 1 and then gelling it multiple times, multiple layers (three layers in this example) of ion-responsive gel layers 2A', 2B', 2C' are formed. Next, with patterning (masking: not shown) applied to the central circular portion of the substrate 1, the substrate 1 is coated with a predetermined metal alkoxide solution for forming an ion-insensitive glass film layer. A thin film of ion-insensitive sol is deposited on the surface of the substrate 1 other than the central circular portion, and then gelled to form an ion-insensitive gelled layer 3, and then heated. The gelled layers 2A', 2B', 2C', and 3' are vitrified by firing to form an ion-selective glass membrane layer 2 on the surface of the substrate l.
It shows an ion-selective glass electrode with a multilayer structure formed by forming A, 2B, and 2C on an ion-insensitive glass membrane layer 3. .

In the embodiments shown in FIGS. 2 and 3 above, the order of formation of the ion-responsive gel layer 2 (2A', 2B2C°) and the ion-insensitive gel layer 3'' is reversed from the above case. Furthermore, the ion-insensitive gel layer 3' may also have a multilayer structure.

Furthermore, in the embodiment shown in FIG.
For example, forming an ion-selective glass film layer formed on the substrate l and the ion-selective glass film layer formed on the surface of the substrate l may be necessary, for example, when there is a large difference in expansion coefficient and there is a risk of peeling problems, or when there is a risk of peeling problems, or when only one layer of ion-selective glass film layer This is very effective in cases where merely forming a selective glass membrane layer does not sufficiently improve basic characteristics such as alkali ion potency, chemical stability, and impedance. In addition, the multiple layers of ion-responsive gelling layer 2A'
, 2B' and 2C' may be the same or different in composition.

Next, as a more specific application example, 9H and pN
In order to easily construct a composite electrode capable of measuring a, we have created a so-called composite ion-selective glass that is a single ion-selective glass electrode but also has a pH-responsive glass electrode part and a pNa-responsive glass electrode part. A third embodiment of the electrode manufacturing method will be described with reference to FIGS. 4 to 7.

First, 13 of 5i (QCsH5)4 as a metal alkoxide necessary to constitute the ion-insensitive glass membrane layer.
．． Add 15mj+ of ethanol to 1g and heat to 80℃
Start stirring at about 12:00 (this will be referred to as ion-insensitive sol A).

In addition, the predetermined pHi! A plurality of types (six types in this example) of metal alkoxides necessary to construct an ion-selective glass membrane layer that exhibits high properties, namely 31 (OCR
! (s)a +Li0C1Hs, Ta (OCm H
s ) s + Ba (OCm Ht )! +La (
OC3H, )3 , Ti (OCm Ht )a, SiOx, LigO, Ta@Os, BaO, La
g 02 , as molar ratio of TIO, (64-x):
(27+x): in the ratio of 2:2:4:l, and x
=3. -2°7 and -12 to produce four types of mixed metal alkoxides, and 50mj of ethanol for each 25g of these mixed metal alkoxides! Add 80
Stir the parts at ℃ for about 12 hours (X-3 is I) H-responsive sol 81. The one with x=-2 is the pH-responsive sol B2. The one with x=-7 is pH-responsive sol B3, X=-12
This is referred to as pH-responsive sol B4).

Furthermore, multiple types of I! are necessary for constructing an ion-selective glass membrane layer that exhibits a predetermined pNa selectivity. Metal alkoxides of ¥ (four types in this example), namely S L (
QCs Ha ) a * Nag OCRHsAI
(QCs Ht : h , B (OCm Hs )s, 5tOH, Nag O, Aft Os , Bt Os
A mixed metal alkoxide mixed at a molar ratio of 66:17:10 is produced, and 50 mj+ of ethanol is added to 20 g of the mixed metal alkoxide.
Stir at 80° C. for about 12 hours (this will be dissolved in response to pNa).

For example, length x width =
Prepare a thin pH-responsive glass substrate 1 with a thickness of 20 mm,
As shown in FIG. 4(a), a first masking M of 5 mmφ is applied to the left and right center portions of both the upper and lower surfaces of the substrate l, respectively.The patterning by such masking M is as follows: Any method can be used, such as resist coating, tape attachment, photosensitive process, etc.

Next, the substrate l that has been patterned as shown in FIG. By attaching a film of ion-insensitive sol to the surface of the area other than the applied area and gelling it, as shown in FIG. 4(b), ion-insensitive gelation 71
form 3'.

Subsequently, after removing the first masking M from the substrate l which has been subjected to the treatment shown in FIG. 4(b), as shown in FIG. 5(a), the substrate l is (the left side first masking M, M
A second masking M° is applied to the area other than the area previously applied.

Next, the substrate 1 which has been patterned as shown in FIG. A thin film of the pH-responsive sol is attached to the area other than the applied area (that is, the center left side of both the upper and lower surfaces) and then gelled. By sequentially repeating the process for B4, as shown in FIG.
Form D.

Further, after removing the second masking M from the substrate l which has been subjected to the treatment shown in FIG. 5(b),
As shown in FIG. 6(a), a third masking M'' is applied to the upper and lower surfaces of the substrate l, except for the right center portion (the portion to which the first maskings M and M were applied on the right side).

Next, the substrate 1 which has been patterned as shown in FIG. 6(A) is immersed in the pNa responsive sol C, and the third masking M
A thin film of pNa-responsive sol is attached to the area other than the area where " is applied (that is, the center right side of both the upper and lower surfaces) and then gelled, and this operation is repeated multiple times (4 times in this example). By repeating the process, as shown in FIG. 6(b), four pNa responsive gelling layers 2a' having the same composition are
, 2b', 2C', 'ld' are formed.

After that, the gelled layer 2A'2B' is heated and baked.
, 2C'2a'2b'2c'
2d'3° is vitrified to form pH-responsive ion-selective glass film layers 2A, 2B, 2C2D and pNa-responsive ion-selective glass film layers 2a, 2b on the surface of the substrate 10.
, 2c, 2d and formed on the ion-insensitive glass film layer 3,
This constitutes a composite ion-selective glass electrode with a multilayer structure.

In this way, it is possible to manufacture a composite ion-selective glass electrode that can detect 2fiM ion concentrations of pH and pNa with a single ion-selective glass electrode; Needless to say, it is also possible to manufacture products whose concentration can be detected.

〔Effect of the invention〕

As is clear from the detailed explanation above, according to the method for manufacturing an ion-selective glass electrode according to the present invention, at least one ion-selective glass film layer is formed at a predetermined location on the surface of a substrate made of an ion-responsive material. , and an ion-insensitive glass film layer is formed on the surface of the substrate at locations other than the ion-selective glass film layer using a patterning method and a blue gel method using a metal alkoxide as a raw material, respectively. By adopting a unique method such as a manufacturing process, it is significantly superior to conventional methods in terms of mass production, economy, stability of quality, diversity of products that can be manufactured, ease of implementation, etc. It has come to be effective.

[Brief explanation of the drawing]

The drawings are for explaining various embodiments of the present invention, and FIG. 1 shows a flowchart representing an example of a conceptual procedure of a basic embodiment of the method for manufacturing an ion-selective glass electrode according to the present invention. , FIG. 2 shows an explanatory diagram of the first embodiment, FIG. 3 shows an explanatory diagram of the second embodiment, and FIGS. 4(a), (b), Figure 5 (a)
, (b) FIGS. 6(a), (b), and 7 show more specific explanatory diagrams of the third embodiment. l: 1&plate, 2 (2A-, 2a-): ion-selective glass membrane layer, 3: ion-insensitive glass membrane layer.

Claims (1)

[Claims] at least one ion-selective glass membrane layer at a predetermined location on the surface of a substrate made of an ion-responsive material, and an ion-insensitive glass membrane layer at a location other than the ion-selective glass membrane layer on the surface of the substrate, 1. A method for producing an ion-selective glass electrode, comprising forming the electrode using a patterning method and a sol-gel method using a metal alkoxide as a raw material, respectively.