JP2005139016A - Method for producing joined member, and micro chemical chip obtained by using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that the flatness of the glass surface of a micro chemical chip, obtained by integrally laminating a plurality of glass sheets and joining the sheets by thermal fusion of glass, is insufficient because of the warpage of the glass sheet. <P>SOLUTION: In the method for producing a joined member, glass members each containing silicon dioxide as a main component are joined to each other, and a solution of a silicon alkoxide compound is used for bonding the joining faces. At the time of joining, heating or an external force is applied onto the joining face to press it in order to increase bonding strength. It is possible to obtain the micro chemical chip having a fine flow passages by integrally laminating a glass sheet having grooves and a glass sheet by the method. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a method for manufacturing a bonded member in which a plurality of members are bonded together, and relates to a microchemical chip obtained by this method.

In recent years, for the purpose of antibody analysis and minimization of chemical reaction fields, chemical reaction chips having minute spaces and channels have been actively used, and glass substrates are bonded together to manufacture such microchemical chips. Matching technology is essential. Conventionally, for bonding glass substrates to each other, there are a fusion method in which the glass substrates are heated to an annealing point or higher, a method using hydrofluoric acid, a method using an alkaline solution, a method using an organic adhesive, and the like. Are known.

For example, in Japanese Patent Application Laid-Open No. 2003-215140 (Patent Document 1) and Japanese Patent Application Laid-Open No. 2003-175330 (Patent Document 2), two glass plates are heated and the glass on the bonding surface is thermally fused. A method of manufacturing a chemical chip is disclosed. JP 2003-54971 A (Patent Document 3) discloses a method in which a bonded surface of a quartz glass component is wetted with water, and the bonded surfaces are brought into close contact with each other under pressure and heated. A method for manufacturing a quartz glass bonding member used as a component is disclosed.

JP 2003-215140 A JP 2003-175330 A JP 2003-54971 A

Further, in an optical lens body known as a contact-type achromatic lens in which a plurality of glass lenses are bonded together, as described in JP-A-2003-139913 (Patent Document 4), the bonding adhesion of lenses is described as follows. A silicone resin having excellent transparency is used as an adhesive for joining the lenses.

JP 2003-139913 A

In the joining of glass members by the heat fusion method, it is essential to heat the glass member to a glass annealing point or higher, so that the surface of the glass member is uneven, and the detection light used for detecting the chemical reaction is There was a problem of scattering due to surface irregularities.

The method of joining glass members using hydrofluoric acid uses a dangerous reagent called hydrofluoric acid, and therefore requires a corresponding equipment and is not a simple method. In addition, when the glass member is a multi-component glass, irregularities are generated on the surface due to the difference in reactivity of hydrofluoric acid to the glass component, and as a result, the glass has a haze (visible defect that appears cloudy). ) Is not suitable as a method for producing a microchemical chip for performing chemical analysis such as photothermal conversion analysis.

The method of bonding glass members using an alkaline solution is that when the glass is a multi-component glass, unevenness occurs in the bonding surface due to the difference in reactivity of the alkali chemicals to the glass component, resulting in haze on the bonding surface. Is likely to occur. For this reason, joining using an alkaline solution is not suitable for manufacturing a microchemical chip for chemical reaction.

The method of applying and bonding an organic adhesive such as silicone resin to the bonding surface is difficult to prevent the adhesive from entering the flow path of the microchemical chip, and the flow path into which the reaction reagent is introduced It is difficult to clean.

The present invention has been made for the purpose of solving the technical problems of the above-described prior art, and the first object of the present invention is to bond and bond a member mainly composed of silicon dioxide at a low temperature. A second object is to provide a microchemical chip in which unnecessary substances such as adhesives do not enter the flow path.

The present invention was obtained in the course of studying a simple bonding method between glass substrates at a lower temperature (below the glass annealing point) and that does not affect the chemical reaction, and is a main component of silicon dioxide. The present inventors have found that interposing a silicon alkoxide solution containing the same kind of metal component in the joint surface is useful for improving the adhesion strength of the joint surface.

The method for manufacturing a bonded member of the present invention is a method for manufacturing a bonded member in which members whose main components are silicon dioxide are bonded to each other, and a solution of a silicon alkoxide compound is used for bonding the bonded surfaces. Features.

Examples of the member whose main component is silicon dioxide include glass and ceramics. Examples of the glass include soda lime silica glass, aluminosilicate glass, aluminoborosilicate glass, and glass mainly composed of silicon dioxide (silica component) such as alkali-free glass.

Although the detailed mechanism for improving the adhesion strength by interposing the silicon alkoxide solution on the joint surface is not clear, the silicon alkoxide solution intervenes on the joint surface, so that the hydroxyl group on the member surface and the silicon alkoxide solution are bonded to each other. It is thought that the two adhere firmly.

The thickness of the silicon alkoxide solution present on the bonding surface is not particularly limited. However, if it is thicker than necessary, the reaction is difficult to proceed and the mechanical strength cannot be maintained. The silicon alkoxide is reduced in the organic component by the bonding with the silicon dioxide component of the member by the hydrolysis reaction, and approaches the glass containing the silicon dioxide component. For this reason, in the microchemical chip, there is no risk of inhibiting the chemical reaction even if the adhesive is in contact with the chemical reaction field in the flow path of the microchemical chip.

The silicon alkoxide compound used as the adhesive of the present invention is represented by the general formula Si (OC _m H _{2m + 1} ) ₄ , and the value of m is any integer from 1 to 3. Organosilicon compounds in which m is 4 or more alkoxides or alkoxyl groups partially substituted with alkyl groups, carbon constituting the compound remains on the bonding surface, resulting in a decrease in adhesive strength and a decrease in light transmittance at the bonding surface. Since it may invite, it is not preferable.

In the present invention, the joining of the members is preferably performed by heating. By heating the members at the time of joining, a larger adhesive strength can be obtained. When the member to be joined is glass, heating to the glass annealing point or higher causes unevenness on the surface of the member, so that the joining is performed at a temperature lower than that. Moreover, it is sufficient to increase the adhesive strength to press the members by applying an external force at the time of joining.

The microchemical chip of the present invention is a microchemical chip in which a glass plate having a groove formed on the main surface and the other glass plate are bonded and bonded so as to form a channel surrounded by the groove and the other glass plate. It is a chip | tip, Comprising: The joining surface is adhere | attached with the hydrolysis product of the silicon alkoxide compound, It is characterized by the above-mentioned.

According to the method for manufacturing a joining member of the present invention, the members can be joined and bonded at a low temperature. In particular, in the case of a glass member, it can be bonded and bonded at a low temperature below the glass transition point, and thus can be bonded without impairing the surface flatness of the glass member. In addition, since it can be joined without using a dangerous reagent such as hydrofluoric acid, it is good for the environment and safety and health.

The microchemical chip with a flow path obtained by joining the glass members of the present invention does not impede the chemical reaction operation because the organic adhesive does not enter the flow path. In addition, since bonding is possible at a low temperature, there is no unevenness on the glass surface or interface, and no light scattering occurs, so that accurate chemical analysis and chemical reaction operation can be performed.

The present invention will be described below with reference to the drawings and examples. 1A and 1B are diagrams for explaining one embodiment of a microchemical chip 1 of the present invention, in which FIG. 1A is a perspective view and FIG. 1B is a cross-sectional view taken along line AA in FIG. The microchemical chip 1 includes a glass plate 3 having a groove 5 on one main surface and the other glass plate 2 having the same dimensions as the glass plate 3, and a groove 5 (which serves as a flow path for the microchemical chip). It is arranged so as to face 2 and is bonded at the joint surface 6. The glass plate 2 and the glass plate 3 are applied and bonded together by dropping a silicon alkoxide, for example, an alcohol solution of silicon alkoxide, on the main surface thereof. If necessary, the glass is heated to a temperature at which no deformation occurs, thereby further strengthening the adhesion. Furthermore, adhesion may be made more reliable by applying a load from above the glass plate 2.

The dimension of glass is about 20 mm x 40 mm, and the thickness is about 0.5 to 1 mm. The groove has a rectangular or cross-sectional shape with a depth of about 0.3 mm and a width of about 0.3 mm, a wet etching method using a photoresist masking material and a hydrofluoric acid that is an etching agent for glass, and a sandblast for spraying a fine grinding stone. It is formed by the law etc.

When viewed from the upper surface of the glass plate, the groove 10 has a Y-shaped pattern composed of two branch portions and one junction portion. Two kinds of sample solutions are injected into each of the branch portions from an injection port (not shown) provided in the glass plate 2 and mixed at the junction portion to perform a chemical reaction operation.

FIG. 2 shows another embodiment of the microchemical chip of the present invention, in which a glass plate 4 provided with a through groove 5 in advance is sandwiched and bonded between the glass plates 2 and 3. Since the silicon alkoxide compound applied to the glass bonding surface 6 does not flow into the groove 5 in the hydrolysis condensation process, the inner wall of the flow path formed by the groove 5 is not contaminated.

Examples 1 to 10
A commercially available soda lime silica glass (annealing point of about 550 ° C.) slide glass was used as the glass plate, and after thoroughly washed, tetraethoxysilane Si (OC ₂ H ₅ ) ₄ was dropped onto the joint surface to prepare two sheets. The slide glass was overlapped. Thereafter, the superposed slide glass was placed horizontally, and the sample temperature was changed as shown in Table 1 to change the standing temperature, the weight of the weight placed thereon, and the standing time.

When the adhesive strength of the bonded glass plate was evaluated by sensory evaluation, the results shown in Table 1 were obtained, and the adhesive strength was significantly improved as compared with Comparative Example 1 described later.

Example 11 to Example 14
A sample was obtained by performing the same bonding treatment as in Example 1 except that the silicon alkoxide shown in Table 1 was dropped and applied to the bonding surface. When the adhesive strength was evaluated by sensory evaluation, the results shown in Table 1 were obtained, and the adhesive strength was significantly improved as compared with Comparative Example 1. In Examples 13 and 14, although the adhesive strength was improved as compared with Comparative Example 1 described later, a light brown color attributed to the carbon compound that was considered to have occurred during heating was observed on the joint surface. This was expected to lead to loss of detection light when used for a chemical reaction chip.

Example 15
A sample was obtained by performing the same bonding treatment as in Example 1 except that borosilicate glass (glass annealing point 560 ° C.) was used as the glass plate. As a result, an adhesive strength equivalent to that of Example 1 could be obtained.

Comparative Example 1
A sample was obtained by performing the same treatment as in Example 1 except that pure water was dropped on the joint surface. Thereafter, an attempt was made to evaluate the adhesive strength, but no adhesion was found.

Comparative Example 2
A sample was obtained by performing the same treatment as in Example 1 except that nothing was dropped on the joint surface and the standing temperature was 500 ° C. in an electric furnace in order to improve the adhesive strength. The glass plate was not bonded at all.

Comparative Example 3
A sample was obtained by performing the same treatment as in Example 1 except that nothing was dropped on the joint surface and the standing temperature was 600 ° C. in order to improve the adhesive strength. Although the adhesive strength was improved, a lot of haze was generated on the glass surface due to surface irregularities, and it could not be used as a microchemical chip for chemical analysis and reaction operation.

Comparative Example 4
A sample was obtained by performing the same treatment as in Example 1 except that a commercially available hydrofluoric acid solution (47%) was dropped onto the joint surface. Although the adhesive strength was improved, haze was generated due to unevenness at the interface, which was not usable for a microchemical chip.

It is used for the production of a microchemical chip having a microchannel by bonding glass plates.

It is a figure explaining one Example of the microchemical chip obtained by implementation of this invention. It is sectional drawing of the other Example of the microchemical chip obtained by implementation of this invention.

Explanation of symbols

1: Micro chemical chip 2, 3, 4: Glass plate 5: Groove (flow path)
6: Joint surface

Claims (5)

A method for manufacturing a bonded member in which members whose main components are silicon dioxide are bonded to each other, wherein a solution of a silicon alkoxide compound is used for bonding the bonded surfaces. 2. The joining member according to claim 1, wherein the silicon alkoxide compound is represented by a general formula Si (OC _m H _{2m + 1} ) ₄ , and a value of m is an integer of 1 to 3. 3. Production method. The method for manufacturing a joining member according to claim 1, wherein the member is heated at the time of joining. The method for manufacturing a joining member according to claim 1, wherein the members are pressed together during joining. A microchemical chip in which a glass plate having a groove formed on the main surface and the other glass plate are bonded and bonded so as to form a channel surrounded by the groove and the other glass plate, the bonding surface Is bonded with a hydrolysis product of a silicon alkoxide compound.

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