JP2778599B2 - Photoinsolubilizing electrolyte composition, pattern forming method using the same, and method for manufacturing electrode element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Summary] The present invention relates to a method for producing a photoinsolubilizable polymer electrolyte composition and an electrode element that can be used for a biosensor. This solution containing a bisazide-based monomer crosslinking agent and a sensitizer is applied to a substrate, partially insolubilized by irradiating light to form a pattern, and this electrolyte pattern is formed at a connection portion between electrodes. Is made to come into contact with an oxidizing atmosphere to solubilize the electrolyte, and to cover it with an oxygen permeable membrane.

[Industrial applications]

The present invention relates to a photo-insolubilizable polymer electrolyte composition, a pattern forming method using the same, and a method for producing an electrode element usable for a biosensor.

The polymer electrolyte is used for manufacturing an element having a high function represented by a biosensor. For example, an electrode element such as an oxygen electrode is used as an indirect measurement target for local changes in oxygen concentration by combining it with an enzyme that oxidizes or reduces only a specific substrate or a microorganism that assimilates a specific substance. Thus, it is possible to form a biosensor that selectively measures only a specific substance.

There are a wide range of substances to be measured by biosensors, such as sugars such as glucose (glucose), sucrose (sucrose), and galactose, and organic acids such as ascorbic acid (vitamin C), lactic acid, and uric acid. Since quick and easy measurement is possible as compared with methods such as liquid chromatography, it can be applied to the fields of food, brewing industry, medical care and clinical examination.

The presence of an electrolyte is essential because the measurement of a biosensor is based on an electrochemical reaction. The present invention relates to a composition that can be used for forming an electrolyte layer that can be applied to devices in the above fields.

[Conventional technology]

Conventionally, the following method has been used for forming an electrolyte layer for producing an electric conversion element using the electrochemical principle.

Apply a photoresist or the like to the substrate, open a window in the area where the electrolyte layer is to be formed, then spread the electrolyte solution in a thin layer by spin coating, dip coating, toctor blade, etc. The portion is removed to form an electrolyte layer on a specific portion (lift-off method).

Apply a photoresist with surface hydrophobicity to the substrate,
A window is opened in a portion where an electrolyte layer is to be formed, and then dip-coated with an aqueous electrolyte solution to cause the electrolyte solution to adhere only to the window portion and then dried.

A mask made of an appropriate material (such as stainless steel) is placed on the substrate, and an electrolyte material is deposited thereon by a vacuum evaporation method or the like.

In any of the above methods, a certain mask is brought into contact with the substrate, and an electrolyte layer is formed only in a portion without the mask.

[Problems to be solved by the invention]

Therefore, in the above-mentioned method, it is necessary to apply or contact another material to the device to be manufactured, which complicates the manufacturing process, and therefore, the product yield is low, and the electrolyte that can be formed is also low. The miniaturization of the layers is also difficult, and thus has become a major obstacle in miniaturizing devices.

In particular, in the above, the relationship between the photoresist stripping target and the dissolution of the electrolyte material is complicated, and it is difficult to select an appropriate solvent.

In this case, the relationship between the surface tension and the viscosity of the electrolyte solution is complicated, and it cannot be applied to those having a high viscosity and a small surface tension like a general polymer electrolyte aqueous solution.

Is convenient for forming a low molecular weight electrolyte layer, but when it is desired to increase the thickness of the electrolyte layer, the time required for vapor deposition becomes extremely long, which is not practical.

In order to overcome the above-mentioned problems, a method has been devised in which a film is formed into a good film, a stable synthetic polymer electrolyte is given photoinsolubility, and a desired pattern of the electrolyte layer is directly obtained by light irradiation (Japanese Patent Application No. Hei 11 (1998) -108). -155207). However, this method uses a divinyl-based monomer as a cross-linking agent for the polymer electrolyte, so that the reaction amount to the irradiation light amount, that is, the sensitivity is low, and long-time light irradiation is required. Had a problem of deterioration. Some attempts have been made to increase the sensitivity by using a bisazide-based reagent as a crosslinking agent. However, the pattern insolubilized by cross-linking becomes gel when impregnated with a solvent, and the volume significantly expands. In particular, in an oxygen electrode formed by forming a fine pattern between the noble metal electrodes and covering this with an oxygen-permeable membrane, the solvent permeates over time, and the gelation of the pattern progresses with the passage of time. There is a drawback that the function is significantly reduced.

The present invention has a high sensitivity of being insolubilized by light irradiation,
Further, it is an object of the present invention to provide a stable polymer electrolyte composition having good film-forming properties and a method for forming an electrolyte pattern using the same, and further manufacturing an electrode element.

[Means for solving the problem]

The above-mentioned problems are a polymer electrolyte, a bisazide-based monomer crosslinking agent, and a photo-insolubilizable electrolyte composition including a sensitizer,
This solution is applied to a substrate and locally irradiated with light to form an electrolyte pattern that does not dissolve in a solvent, and this electrolyte pattern is formed at a connection portion between the electrodes, and then brought into contact with an oxidizing atmosphere. This can be solved by a method of manufacturing an electrode element including a step of solubilizing an electrolyte and coating an oxygen permeable membrane thereon.

[Action]

As the polymer electrolyte, a polymer having an acid group or activated nitrogen, sulfur or phosphorus, for example, a substance having a repeating unit shown in the following table can be used.

As the bisazide-based monomer, a substance capable of decomposing an azide group by light irradiation to release a nitrogen molecule and activating the remaining nitrogen atom can be used. The activated nitrogen abstracts hydrogen atoms from the main chain of the polyelectrolyte, so the polyelectrolyte creates unsaturated bonds in the main chain, which causes a crosslinking reaction, and only the light-irradiated portion decreases the solubility in the solvent. This part forms a pattern.

 For example, the following monomers can be used:

Etc. can be used.

As the sensitizer, commonly used photoinitiators, for example, dyes such as methylene blue, rhodamine, and riboflavin can be used. Light 250-3 to start the reaction
Although it is preferable to use 50 nm ultraviolet light, visible light can be used depending on the type of the sensitizer.

After the light irradiation, a local solvent such as water, alcohol, or dimethylformaldehyde is used as a solvent, and a portion of the polymer electrolyte which has not been irradiated with light is dissolved and removed to form a pattern.

After the pattern is formed, oxygen gas, ozone gas, or the like can be used as the oxidizing atmosphere for solubilizing the polymer again.

In forming the electrolyte layer on the substrate of the electrochemical element, after uniformly applying a solution of the composition according to the present invention to the substrate and drying, a specific portion is irradiated with light to form a pattern having a desired shape. Can be formed. As a result, a fine pattern can be easily formed, and since the electrolyte layer to be patterned is uniform, characteristics as a final device are also uniformed.

In addition, the sensitivity to light is about 10 times higher than when a divinyl monomer is used as a crosslinking agent. Therefore, deterioration of the polymer electrolyte due to light at the time of patterning can be reduced.

Furthermore, since the electrolyte pattern is brought into contact with an oxidizing atmosphere to be solubilized again and then coated with the oxygen-permeable film, damage to the film due to gelation of the pattern can be prevented.

〔Example〕

Example FIG. 1 shows a procedure for producing an oxygen electrode for forming an electrolyte using the photoinsolubilizable electrolyte composition of the present invention. As the photo-insolubilizing electrolyte composition, poly- (N-ethyl-4) is used.
-In a 10% aqueous solution of vinylviridinium bromide,
An aqueous solution in which sodium 4'diazidostilbene-2,2'-disulfonate was dissolved at 1% and rhodamine B at 0.1% was used. Hereinafter, the manufacturing method will be described step by step.

FIGS. 1A and 1G: An electrode pattern was formed on a glass substrate 1 by sputtering platinum and vacuum depositing silver. A plan view of the pattern is as shown in FIG.

The platinum cathode electrode 2 and the silver anode electrode 3 were formed through the following steps, respectively. A glass substrate is placed on one electrode of a parallel plate type sputtering apparatus, a platinum plate is placed on the other electrode side, a high frequency power of 13 MHz is applied between both electrodes, and argon gas is introduced, 5 × 10 ^-7 Torr
Then, the cathode electrode 2 having a thickness of 1000 mm was formed on the glass substrate 1 by platinum sputtering through a hole of a stainless steel mask placed on the glass electrode. Next, the glass substrate 1 is set in a vacuum evaporation apparatus, and silver is vacuum-deposited on the glass substrate 1 through a hole of a stainless steel mask placed on the glass substrate. Was formed.

FIGS. 1 (B) and 1 (C): Next, the photoinsolubilizable electrolyte composition was applied and dried by spin coating to form a film having a thickness of 50 μm.

FIG. 1 (D), FIG. 1 (E), FIG. 1 (H): A photomask for irradiating the anode part and the cathode part with light is placed on this substrate, and the light of a 500 W high-pressure mercury lamp is placed. To
After irradiating for 10 seconds, the polymer electrolyte layer was immersed in ethanol and developed to form an insolubilized polymer electrolyte layer only in the portion irradiated with light. The plan view of the pattern is as shown in FIG.

Place the substrate in a quartz container under a steam-saturated oxygen stream,
Ultraviolet rays were irradiated from the outside through a quartz window for 10 minutes. As a result, the electrolyte in the pattern is reduced in molecular weight and becomes soluble in water, and does not gel.

FIG. 1 (F): OMR-83 (Tokyo Ohka Co., Ltd.) which is a negative resist is applied as a material for an oxygen-permeable film on the surface of the substrate by dip coating, and dried at 80 ° C. for 20 minutes. 60 UV
Irradiation for 20 seconds, and reheating at 120 ° C. for 20 minutes, the oxygen permeable membrane 5 was formed. The thickness of the formed oxygen permeable membrane is about 20μm
Met.

The yield of the completed oxygen electrode was over 99%. Also, when the oxygen electrode was immersed in water saturated with air and the response characteristics were examined at a voltage between anode and cathode of 0.8 V,
Output fluctuations were within ± 3%. Further, the oxygen permeable membrane was not damaged during use.

Comparative Example In FIG. 1 (H), the electrode element manufactured in the same manner as in the example except that the step of irradiating the patterned crosslinked polymer electrolyte with ultraviolet light in an oxygen stream was not used in water. In addition, about half of the samples were broken due to swelling of the electrolyte pattern, resulting in breakage of the oxygen permeable membrane.

〔The invention's effect〕

According to the present invention, it is possible to form an electrolyte layer, which plays the most important role in producing an electrochemical measurement element, particularly an oxygen electrode, by light irradiation, thereby improving the yield and uniformity of characteristics of the element. In addition, the response speed of the element can be increased. In addition, the sensitivity of the electrolyte when insolubilized by light irradiation is remarkably improved as compared with the related art, so that photodeterioration of the polymer electrolyte is reduced and reliability is improved. Furthermore, during use as an electrode element, the polymer electrolyte swells,
The oxygen permeable membrane is not damaged.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view and a plan view showing a process of manufacturing an oxygen electrode using the photo-insolubilizing polymer electrolyte of the present invention. In the figure, 1 is a glass substrate, 2 is a platinum cathode, 3 is a silver anode, 4 is a photo-insolubilizing electrolyte, 5 is a photomask, and 6 is an oxygen permeable membrane.

Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI G03F 7/038 G03F 7/038 // G01N 27/404 G01N 27/30 341Z (72) Inventor Naomi Kojima 1015 Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Address Fujitsu Limited (56) References JP-A-3-20304 (JP, A) JP-A-62-159140 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C08F 2 / 00-2/60 C08L 1/00-101/14 G03F 7/00-7/038 C09D 4/00-4/06 C08F 291/00-291/18

Claims (3)

(57) [Claims] 1. A photo-insolubilizable electrolyte composition comprising a polymer electrolyte, a bisazide-based monomer crosslinking agent, and a sensitizer. 2. A solution of the photo-insolubilizing electrolyte composition according to claim 1, applied to a substrate, and locally irradiated with light to form an electrolyte pattern that is not dissolved in a solvent.
Pattern formation method. 3. A solution of the photo-insolubilizing electrolyte composition according to claim 1 is applied to a substrate, and a portion connecting between the electrodes is irradiated with light to form an electrolyte pattern that is not dissolved in a solvent, and then oxidized. A method for producing an electrode element, comprising the steps of: solubilizing an electrolyte of a pattern by contacting with an oxidizing atmosphere, and coating an oxygen-permeable membrane thereon.