WO2009119440A1

WO2009119440A1 - Microchip and molding die

Info

Publication number: WO2009119440A1
Application number: PCT/JP2009/055433
Authority: WO
Inventors: 信高木; 幹司関原
Original assignee: コニカミノルタオプト株式会社
Priority date: 2008-03-27
Filing date: 2009-03-19
Publication date: 2009-10-01
Also published as: TW200948706A

Abstract

Provided is a microchip in which the transferability in molding can be evaluated without quantitatively measuring the shapes of flow channel grooves. A first flow channel groove (2) and a second flow channel groove (3) are formed to intersect each other in one surface of a resinous substrate (1). A step portion (5) is provided at an intersection thereof. The depth d1 of the first flow channel groove (2) and the depth d2 of the second flow channel groove (3) have a relationship of depth d2 > depth d1, and a difference δt in depth is the height of the step portion (5). The flow channel grooves of the resinous substrate (1) are fabricated by molding using a molding die. The step portion (5) is used for evaluating the transferability in the molding. The shape of the step portion (5) is observed by an observation device such as a microscope, and the transferability is evaluated on the basis of the observation.

Description

Microchip and mold for molding

This invention relates to a microchip manufactured by bonding a resin substrate on which a channel groove is formed. The present invention also relates to a molding die for producing a resin substrate in which a channel groove is formed.

A micro-analysis chip that uses microfabrication technology to form fine channels and circuits on silicon and glass substrates, and to perform chemical reactions, separation, and analysis of liquid samples such as nucleic acids, proteins, and blood in a minute space Alternatively, an apparatus called μTAS (Micro Total Analysis Systems) has been put into practical use. As an advantage of such a microchip, it is conceivable to realize an inexpensive system that can be carried in a small space because the amount of sample or reagent used or the amount of discharged waste liquid is reduced.

A microchip is manufactured by bonding two members having at least one member subjected to microfabrication. Conventionally, a glass substrate is used for the microchip, and various fine processing methods have been proposed. However, since glass substrates are not suitable for mass production and are extremely expensive, development of inexpensive and disposable resin microchips is desired.

In order to manufacture a resin microchip, a resin substrate on which a channel groove is formed and a resin substrate that covers the channel groove are joined. The resin substrate on which the channel grooves are formed is produced by, for example, injection molding. Conventionally, in order to promote a swirling flow of liquid in a fine channel, there has been proposed a microchip in which a channel groove is formed by branching a plurality of channels in which spiral irregularities are formed in a channel groove by molding. (Patent Document 1).
JP 2006-142210 A

However, as disclosed in Patent Document 1, many of the recent channel grooves have a complicated pattern in which a plurality of channels are branched and intersected. When such a complicated flow path groove pattern is formed by injection molding, the resin transferability during molding may not be sufficient over the entire flow path groove. In that case, the transferability at a plurality of locations in the flow path is measured and evaluated, but there is a problem that it takes time to evaluate the transferability for each flow path. Moreover, the method of evaluating the evaluation based on the measurement result based on the measuring apparatus requires time for inspection, and it is further difficult to easily evaluate the transferability in molding. Also, the measuring device used for the measurement is expensive. Therefore, there has been a demand for a method that can reduce labor and cost required for inspection and can easily evaluate transferability by molding.

The present invention solves the above problems, and even when such a complicated flow groove pattern is formed, the transferability in molding can be evaluated without measuring each flow groove. It is an object of the present invention to provide a molding die for producing a microchip and a resin substrate in which a channel groove is formed.

According to a first aspect of the present invention, a channel groove is formed on the surface of at least one of the two resin substrates produced by molding a resin, and the two resin substrates are formed. Are joined with the surface on which the channel groove is formed facing inward, and the channel groove intersects the first channel groove and the first channel groove. The microchip includes a two-channel groove, wherein the first channel groove and the second channel groove have different groove depths.

According to a second aspect of the present invention, there is provided a microchip according to the first aspect, wherein there is a step formed at an intersection where the first flow path groove and the second flow path groove intersect. It is used for inspection of transferability in molding.

According to a third aspect of the present invention, there is provided the microchip according to the first aspect or the second aspect, wherein the first flow path groove and the second flow path groove intersect. The height of the step at the intersection is in the range of 0.3% to 5% of the deeper groove depth of the groove depth of the first flow path groove and the groove depth of the second flow path groove. It is characterized by being set to.

According to a fourth aspect of the present invention, at least two flow path grooves are formed to intersect each other on the surface of one of the at least two resin substrates, and the two resin substrates. A molding die for molding the resin substrate formed with the channel groove of the microchip to be joined with the surface on which the plurality of channel grooves are formed inside. A first convex portion corresponding to one of at least two intersecting channel grooves, and corresponding to a position of an upper surface of the first convex portion where the at least two channel grooves intersect The molding die is characterized in that a second convex portion is provided at a position where a step having the same width as that of at least one of the two flow path grooves is provided.

Further, a fifth aspect of the present invention is a molding die according to the fourth aspect, wherein the second convex portion is used for inspection of transferability in molding.

Further, a sixth aspect of the present invention is a molding die according to either the fourth aspect or the fifth aspect, wherein the height of the second convex part is the first convex part and the above-mentioned It is characterized by being set in the range of 0.3% to 5% of the total height of the second convex portion.

According to a seventh aspect of the present invention, there is provided a molding die according to any one of the fourth to sixth aspects, wherein each of the plurality of recesses is etched by etching so that the plurality of recesses intersect. By forming, using the electroforming master in which a step is formed on the bottom surface of the recess at the intersecting intersection, the projection corresponding to the recess is formed by electroforming.

According to the present invention, the step is provided at the intersection where the channel grooves intersect, and the transferability of the channel groove can be evaluated by the step at the intersection. Such a configuration is made in view of the knowledge that there is a possibility that the resin transferability at the time of injection molding may be the least satisfactory at an intersection where a plurality of flow paths intersect. In other words, by evaluating the resin transferability by providing stepped portions formed at the intersections, it is possible to evaluate a few intersections without having to evaluate the transferability of the shape of each channel groove one by one. As a result, it is possible to evaluate the transferability of the groove for the flow path with respect to the resin substrate, the labor can be reduced, and even the cost-related evaluation using the measuring apparatus leads to cost reduction.

In addition, by forming a step deeper than the step of the flow path, transferability can be easily estimated by observation evaluation using a microscope, etc., without using evaluation based on measurement results based on a measurement device. In that case, it leads to further cost reduction.

1 is a top view of a resin substrate according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of a resin substrate according to an embodiment of the present invention, and is a cross-sectional view taken along the line II-II in FIG. It is sectional drawing of the microchip which concerns on embodiment of this invention. 1 is a top view of an electroforming master according to an embodiment of the present invention. FIG. 5 is a cross-sectional view of an electroforming master according to an embodiment of the present invention, and is a VV cross-sectional view of FIG. It is sectional drawing of the metal mold | die for shaping | molding which concerns on embodiment of this invention. 1 is an enlarged cross-sectional view of a part of a molding die according to an embodiment of the present invention. It is a top view of the resin-made board | substrates concerning a modification. FIG. 9 is a cross-sectional view of a resin substrate according to a modification, and is a IX-IX cross-sectional view of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1A, 6

Resin substrate

2, 2A

1st channel groove

3, 3A

2nd channel groove

4, 4A, 13

Intersection

5, 5A, 14, 23 Step part 7 Through hole 8 Microchip 10 Electricity Casting master 11 First flow path forming groove 12 Second flow path forming groove 20 Molding die 21 First convex portion 22 Second convex portion

A microchip according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a top view of a resin substrate according to an embodiment of the present invention. 2 is a cross-sectional view of the resin substrate according to the embodiment of the present invention, and is a cross-sectional view taken along the line II-II in FIG. FIG. 3 is a cross-sectional view of a microchip according to an embodiment of the present invention.

As shown in FIG. 1, the resin substrate 1 is a plate-like substrate, and a linear first flow channel groove 2 and a straight second flow channel groove are formed on one surface of the resin substrate 1. 3 are formed. In this embodiment, as an example, the first flow path groove 2 and the second flow path groove 3 are formed orthogonally on the surface of the resin substrate 1. The first flow path groove 2 and the second flow path groove 3 may be formed on the resin substrate 1 without being orthogonal to each other.

Further, the depth of the first flow path groove 2 and the depth of the second flow path groove 3 are different, and the first flow path groove 2 and the second flow path groove 3 intersect each other at the bottom surface of the intersection 4. A step portion 5 is formed. In this embodiment, the depth of the second flow path groove 3 is deeper than the depth of the first flow path groove 2. Therefore, a stepped portion 5 that is orthogonal to the length direction of the first flow path groove 2 is formed on the bottom surface of the intersecting portion 4 across the width direction of the first flow path groove 2. The step portion 5 has the same width as the width of the first flow path groove 2. In addition, by making the depth of the first flow path groove 2 deeper than the depth of the second flow path groove 3, the second flow path groove 3 extends across the width direction of the second flow path groove 3. You may form the level | step-difference part orthogonal to this length direction.

For example, as shown in FIG. 2, the depth of the first flow path groove 2 is defined as depth d1, and the depth of the second flow path groove 3 is defined as depth d2. In this embodiment, since the depth of the second flow path groove 3 is deeper than the depth of the first flow path groove 2, the relationship of depth d2> depth d1 is established, and the difference in depth δt is the height of the stepped portion 5.

Further, the resin substrate 6 which is a counterpart of the resin substrate 1 is a flat substrate. Then, as shown in FIG. 3, the resin substrate 1 and the resin substrate 6 are joined with the surface on which the first flow path groove 2 and the second flow path groove 3 are formed facing inward. The microchip 8 is manufactured. By this bonding, the resin substrate 6 functions as a cover (cover) for the first flow path groove 2 and the second flow path groove 3. As a result, a fine flow path is formed by the first flow path groove 2 and the resin substrate 6 formed in the resin substrate 1, and the fine flow path is formed by the second flow path groove 3 and the resin substrate 6. Is formed.

The resin substrate 6 has a thickness direction of the resin substrate 6 at positions corresponding to both ends of the first flow path groove 2 and positions corresponding to both ends of the second flow path groove 3. A through hole 7 penetrating therethrough is formed. By bonding the resin substrate 1 and the resin substrate 6, an opening corresponding to the through hole 7 is formed in the microchip 8. The opening part by this through-hole 7 is connected to the fine flow path, and is a hole for introducing, storing, or discharging the gel, sample, and buffer solution. The shape of the opening (through hole 7) may be various shapes other than a circular shape or a rectangular shape. A tube or nozzle provided in the analyzer is connected to the opening, and a gel, sample, buffer solution, or the like is introduced into the fine channel through the tube or nozzle, or a sample or the like is removed from the fine channel. Discharge.

It should be noted that a through hole may be provided in the resin substrate 1 without providing the through hole 7 in the resin substrate 6. For example, through holes penetrating in the thickness direction of the resin substrate 1 are formed at both ends of the first flow path groove 2, and the thickness of the resin substrate 1 is formed at both ends of the second flow path groove 3. A through hole penetrating in the direction is formed. Then, by joining the resin substrate 1 and the resin substrate 6, an opening connected to the fine flow path may be formed by a through hole formed in the resin substrate 1.

The shape of the resin substrates 1 and 6 may be any shape as long as it is easy to handle and analyze. For example, a size of 10 mm square to 200 mm square is preferable, and a size of 10 mm square to 100 mm square is more preferable. The shape of the resin substrates 1 and 6 may be matched to the analysis method and the analysis apparatus, and a shape such as a square, a rectangle, or a circle is preferable. Moreover, the diameter of the through-hole 7 should just be match | combined with an analysis method or an analyzer, and it is preferable that it is about 2 mm, for example.

The shape of the first flow channel groove 2 and the second flow channel groove 3 is that the amount of analysis sample and reagent used can be reduced, the production accuracy of the mold, transferability, releasability, etc. The width and depth are preferably values in the range of 10 μm to 200 μm, but are not particularly limited. The aspect ratio (groove depth / groove width) is preferably 0.1 to 3, and more preferably 0.2 to 2. The width and depth of the first channel groove 2 and the second channel groove 3 may be determined according to the use of the microchip. In order to simplify the explanation, the cross-sectional shapes of the first flow path groove 2 and the second flow path groove 3 shown in FIG. 2 are rectangular. It is an example and may be curved.

The plate thickness of the resin substrate 1 on which the first flow path groove 2 and the second flow path groove 3 are formed is preferably 0.2 mm to 5 mm in consideration of moldability, and preferably 0.5 mm to 2 mm is more preferable. The plate thickness of the resin substrate 6 that functions as a lid (cover) for covering the first flow path groove 2 and the second flow path groove 3 is preferably 0.2 mm to 5 mm in consideration of moldability. 0.5 mm to 2 mm is more preferable. In addition, when the flow path groove is not formed in the resin substrate 6 that functions as a lid (cover), a film (sheet-like member) may be used. In this case, the thickness of the film is preferably 30 μm to 300 μm, and more preferably 50 μm to 150 μm.
(Material of resin substrate)
Resin is used for the resin substrates 1 and 6. Examples of the resin include good moldability (transferability and releasability), high transparency, and low autofluorescence with respect to ultraviolet rays and visible light, but are not particularly limited. Absent. For example, polycarbonate, polymethyl methacrylate, polystyrene, polyacrylonitrile, polyvinyl chloride, polyethylene terephthalate, nylon 6, nylon 66, polyvinyl acetate, polyvinylidene chloride, polypropylene, polyisoprene, polyethylene, polydimethylsiloxane, cyclic polyolefin, etc. preferable. In particular, polymethyl methacrylate and cyclic polyolefin are preferable. The resin substrate 1 and the resin substrate 6 may be made of the same material or different materials.
(Joining resin substrates)
The resin substrate 1 and the resin substrate 6 are joined with the surface on which the first flow path groove 2 and the second flow path groove 3 are formed facing inward. The bonding of the resin substrates can be performed by, for example, heat fusion, ultrasonic fusion, or laser fusion. Further, the resin substrate may be bonded by activating the surface of the resin substrate with ultraviolet light, plasma, or ion beam.

It should be noted that a flow path groove may also be formed in the resin substrate 6 and the resin substrates having the flow rate groove formed thereon may be joined together. For example, by bonding the resin substrate 1 and the resin substrate 6 with the flow channel groove formed on the resin substrate 6 on the inside and the flow channel groove formed on the resin substrate 1 on the inside, Make a microchip. A plurality of resin substrates may be stacked and bonded.

The step portion 5 formed at the intersecting portion 4 where the first channel groove 2 and the second channel groove 3 intersect is used for evaluating the transferability of the channel groove in molding. The resin substrate 1 is manufactured by an injection molding method using a molding die. The molding die is formed with a convex portion corresponding to the first flow channel groove 2 and a convex portion corresponding to the second flow channel groove 3, and the shape of the convex portion of the molding die is a resin. The resin substrate 1 having the first flow path groove 2 and the second flow path groove 3 is produced. Furthermore, a step portion is provided on the upper surface of the convex portion of the molding die, at a position corresponding to the intersecting portion 4 where the first flow path groove 2 and the second flow path groove 3 intersect. Thereby, the step of the molding die is transferred to the resin, and the step portion 5 is formed on the bottom surface of the intersecting portion 4 where the first flow path groove 2 and the second flow path groove 3 intersect.

Then, by observing the shape of the step portion 5 formed on the resin substrate 1, the transferability of the first channel groove 2 and the second channel groove 3 can be evaluated. For example, using an observation device such as a microscope, the shape of the stepped portion 5 formed on the resin substrate 1 is compared with the shape of the stepped portion formed on the molding die, based on the difference in the shape of the stepped portion. Transferability can be evaluated. If the shape of the stepped portion 5 of the resin substrate 1 which is a molded product is maintained in view of the shape of the stepped portion of the molding die, the molding die is sufficiently filled with resin, and intersects there. It can be determined that the transfer of the entire first flow path groove 2 and the second flow path groove 3 is good. On the other hand, when the shape of the stepped portion 5 of the resin substrate 1 is not maintained, the molding die is not sufficiently filled with the resin, and the first flow path groove 2 and the second flow passage 2 intersect therewith. It can be determined that the transfer of the channel 3 is insufficient. As described above, according to the microchip using the resin substrate 1 according to this embodiment, it is possible to measure the level difference of the intersecting portion without measuring the shape of each channel groove, that is, the most transferable. By measuring the level difference at the intersection where there is a concern, it is possible to evaluate the transferability of the entire channel groove intersecting there. In addition, since it has a step shape that is deeper than the step of the channel groove, it is possible to transfer the channel groove using an observation device such as a microscope without measuring with a measuring device and evaluating it based on the measurement result. It becomes possible to evaluate sex. As a result, the cost required for inspection can be reduced, and the transferability by molding can be easily evaluated.

Further, by providing the step portion 5 at the intersection 4 where the first flow path groove 2 and the second flow path groove 3 intersect, the transferability can be evaluated at a deep portion of the flow path groove. By providing the stepped portion 5 at the intersecting portion 4, the depth of one of the flow channel grooves becomes deeper than the depth of the other flow channel grooves at the intersecting portion 4. In this embodiment, the depth of the second flow path groove 3 is deeper than the depth of the first flow path groove 2. Thus, at the intersection 4 where the flow path grooves intersect, the flow path grooves having different depths intersect with each other by the stepped portion 5. Therefore, by observing the shape of the stepped portion 5, it becomes possible to evaluate the transferability of the molding in the deep groove portion, and the transferability of the channel groove to the entire resin substrate 1 is evaluated by the evaluation. It becomes possible to do. In other words, if the transferability is good in the portion where the groove depth is deep, it can be estimated that the transferability is good even in the portion where the groove depth is shallow. Thus, by evaluating using the level | step-difference part 5 of the cross | intersection part 4, the necessity to evaluate the transcription | transfer state of every groove | channel is reduced, and the transfer of the whole flow-path groove | channel is simply made favorable. Can be determined.

Further, such a stepped portion 5 can relatively easily specify the position when inspecting transferability. As a result, the time required for the inspection can be shortened. If a step for inspection is provided at an arbitrary position in the channel groove, it is necessary to search for the place where the step is provided by an inspection device such as a microscope when inspecting transferability. In this embodiment, since the level difference part 5 is provided in the intersection part 4, the level difference part 5 can pinpoint a place immediately by a flow-path pattern. In the case of a step at an arbitrary position other than the intersection, is the step found as a step based on the step provided in the molding die or a step formed by another factor? Therefore, it is difficult to evaluate transferability with high accuracy.

In addition, if the stepped portion cannot be found by an observation device such as a microscope, the stepped portion was not transferred due to poor transferability even though the stepped portion was formed on the molding die. It is difficult to determine whether or not the step portion is not provided at the place being observed. Therefore, when all the locations of the channel groove are observed with an observation device such as a microscope, and no stepped portion is found at any location, it can be determined that the transfer property of the channel groove is poor. Further, even when a step portion is found in the channel groove, as described above, it is difficult to determine whether or not the step portion is based on the step portion formed in the molding die. .

On the other hand, according to the resin substrate 1 according to this embodiment, since the crossing portion 4 has the stepped portion 5, the stepped portion 5 can be easily specified, and further, the stepped portion 5 at the crossing portion 4 can be specified. By confirming the shape, the transferability of the resin substrate 1 can be evaluated.

If the height of the step portion 5 is too high, turbulence may occur in the sample flowing in the microchip at the step portion 5, and as a result, the analysis using the microchip may be affected. . In particular, since such a step is provided at a portion where the flow paths intersect, a more severe restriction on the step height is required as compared with other steps. Therefore, the height δt of the step portion 5 is preferably set in a range of 0.3% to 5% of the depth d2 of the second flow path groove 3. Further, the height δt of the stepped portion 5 only needs to be high enough that the inspector can recognize the shape of the stepped portion 5 with a microscope or the like when the transfer is performed well. For example, the height δt of the step portion 5 is preferably 0.01 μm to 1 μm.

In the resin substrate 1 according to this embodiment, one intersecting portion 4 is formed and a stepped portion 5 is provided at the intersecting portion 4, but the present invention is not limited to this example. For example, a plurality of step portions may be provided by forming a plurality of flow channel grooves in the resin substrate so that a plurality of intersections are formed. And when evaluating the transferability in shaping | molding, the shape of the level | step-difference part in each cross | intersection part may be observed with observation apparatuses, such as a microscope, and transferability may be evaluated based on the observation result. Moreover, when providing a several level | step-difference part, the height of each level | step-difference part may be the same height, and may differ in each height. For example, two step portions 5 are formed on the resin substrate 1 according to this embodiment. The heights of these two step portions 5 may be the same height or different heights. Further, the step portion 5 may be provided over the width direction of the first flow path groove 2, and the step portion may be further provided along the width direction of the second flow path groove 3.

In the resin substrate 1 according to this embodiment, the first flow path groove 2 and the second flow path groove 3 are orthogonal to each other, but the present invention is not limited to this example. For example, the channel groove may be formed in a Y shape or a T shape, and a stepped portion may be provided at a branch point where the channel groove branches or at an intersection where the channel groove intersects. In other words, the “first channel groove” and the “second channel groove” according to the present invention are both grooves formed in a straight line, and have intersections where they intersect each other. In this sense, the above-mentioned Y-shaped channel groove and T-shaped channel groove are also included in this category. Further, when three or more flow path grooves intersect, the stepped portion is not limited to one provided with one stepped portion, and two or more stepped portions may be provided. In the case where a step portion is provided at the branch point where the flow channel groove branches, similarly to the resin substrate 1 according to this embodiment, by observing the step portion with an observation device such as a microscope, Transferability can be evaluated.
(Production method)
In order to produce the resin substrate 1 on which the step portion 5 is formed, a molding die having a step portion corresponding to the step portion 5 is used. The mold is processed by a known etching process. Convex portions corresponding to the first flow path grooves 2 and the second flow path grooves 3 are formed on the molding die, and further, a step portion corresponding to the step portion 5 is formed on the upper surface of the convex portion. In this embodiment, a stepped portion corresponding to the stepped portion 5 is provided on the upper surface of the convex portion at a position corresponding to the intersecting portion 4 where the first flow path groove 2 and the second flow path groove 3 intersect. Form. Further, the molding die may be produced by electroforming. In this case, a flow path forming groove corresponding to the first flow path groove 2 and the second flow path groove 3 is formed in the electroforming master by etching. Then, a molding die is produced by the electroforming master.

Here, as an example, a case where a molding die is produced by electroforming and the resin substrate 1 is produced using the molding die will be described with reference to FIGS. 4 to 6. FIG. 4 is a top view of the electroforming master according to the embodiment of the present invention. FIG. 5 is a cross-sectional view of the electroforming master according to the embodiment of the present invention, and is a VV cross-sectional view of FIG. FIG. 6 is a cross-sectional view of a molding die according to an embodiment of the present invention.

As shown in FIG. 4, a linear first flow path forming groove 11 and a straight second flow path forming groove 12 are formed on one surface of the electroforming master 10. In this embodiment, as an example, the first flow path forming groove 11 and the second flow path forming groove 12 are formed orthogonally on the surface of the electroforming master 10.

Further, the depth of the first flow path forming groove 11 and the depth of the second flow path forming groove 12 are different, and the intersection where the first flow path forming groove 11 and the second flow path forming groove 12 intersect. A step portion 14 is formed on the bottom surface of 13. In this embodiment, the depth of the second flow path forming groove 12 is deeper than the depth of the first flow path forming groove 11. Therefore, a stepped portion 14 that is orthogonal to the length direction of the first flow path forming groove 11 is formed on the bottom surface of the intersecting portion 13 across the width direction of the first flow path forming groove 11. The step portion 14 corresponds to the step portion 5 formed on the resin substrate 1. In addition, the second flow path is formed across the width direction of the second flow path forming groove 12 by making the depth of the first flow path forming groove 11 deeper than the depth of the second flow path forming groove 12. You may form the level | step-difference part orthogonal to the length direction of the groove | channel 12 for formation.

For example, as shown in FIG. 5, there is a relationship of depth d2> depth d1 between the depth d1 of the first flow path forming groove 11 and the depth d2 of the second flow path forming groove 12. The depth difference δt is established and becomes the height of the step portion 14.

Next, a method for manufacturing the electroforming master 10 will be described. First, a metal layer is formed on the surface of the master blank by performing Ni—P plating or Cu plating on the master blank. Thereafter, the first flow path forming groove 11 and the second flow path forming groove 12 are formed by etching the upper surface of the metal layer. The electroforming master 10 obtained in this way becomes a base of a molding die for the resin substrate 1. The first flow path forming groove 11 corresponds to the first flow path groove 2 of the resin substrate 1, and the second flow path forming groove 12 corresponds to the second flow path groove 3 of the resin substrate 1. The step portion 14 corresponds to the step portion 5 of the resin substrate 1. Note that the metal layer may not be formed on the master blank. For example, the master blank may be made of a material such as an aluminum alloy or oxygen-free copper, and the master blank 10 may be manufactured by etching the master blank.

Then, an electroformed body is produced by electroforming the electroformed master 10, and then the electroformed body is released from the electroformed master 10. Thereby, the molding die which has a convex part corresponding to the groove for channel formation of electroforming master 10 can be produced.

A molding die produced by the electroforming master 10 is shown in FIG. On one surface of the molding die 20, a linear first convex portion 21 corresponding to the first flow path forming groove 11 and a linear second convex corresponding to the second flow path forming groove 12 are formed. A portion 22 is formed. The height of the first convex portion 21 and the height of the second convex portion 22 are different, and a step portion 23 is formed on the upper surface of the intersection where the first convex portion 21 and the second convex portion 22 intersect. In this embodiment, the height of the second convex portion 22 is higher than the height of the first convex portion 21. The relationship of height d2> height d1 is established between the height d1 of the first convex portion 21 and the height d2 of the second convex portion 22, and the height difference δt is It becomes height.

Then, the resin substrate 1 on which the first flow path groove 2, the second flow path groove 3, and the stepped portion 5 are formed is manufactured by injection molding of the resin using the molding die 20. A first flow path groove 2 having a depth d1 is formed by the first convex portion 21, and a second flow path groove 3 having a depth d2 is formed by the second convex portion 22. Further, the intersection 4 where the first flow path groove 2 and the second flow path groove 3 intersect with each other by the step portion 23 formed at the intersection where the first convex part 21 and the second convex part 22 intersect. A stepped portion 5 is formed on the surface.

When the transferability of the resin substrate 1 is evaluated, the shape of the step portion 5 formed on the resin substrate 1 is observed with an observation device such as a microscope, and the shape of the step portion 5 and the molding die 20 are formed. The shape of the stepped portion 23 is compared. Then, the transferability is evaluated based on the difference in the shape of the step portion.

Here, the transferability of the channel groove will be described with reference to FIG. FIG. 7 is an enlarged cross-sectional view of a part of the molding die according to the embodiment of the present invention. For example, the resin substrate 1 is manufactured by injection molding using a mold in which a flat groove for forming a cavity is formed and the molding mold 20 according to this embodiment. With the flat groove inside, the molding die 20 and the mold in which the groove is formed face each other and are brought into contact with each other, so that the molding die 20 and the mold in which the groove is formed are in contact with each other. Cavity is formed in By filling the cavity with resin, the resin substrate 1 to which the shape of the first protrusion 21 and the shape of the second protrusion 22 are transferred is produced.

For example, as shown in FIG. 7A, when the cavity formed by the molding die 20 is sufficiently filled with resin, the shape of the step portion 23 formed in the molding die 20 is made of resin. Good transfer onto the substrate 1. Specifically, the shape of the corner of the step portion 23 and the shape of the wall portion are transferred to the resin substrate 1, and the step portion 5 having a shape corresponding to the shape of the step portion 23 is formed on the resin substrate 1. The And when the level difference part 5 is observed with observation apparatuses, such as a microscope, the boundary line of the level difference part 5 can be recognized with a comparatively dark line. As a result, the inspector can confirm that the transfer has been successfully performed.

On the other hand, as shown in FIG. 7B, when the resin formed in the cavity formed by the molding die 20 is not sufficiently filled, the shape of the step portion 23 formed in the molding die 20 is resin. It is not transferred well to the substrate 1. Specifically, the shape of the corner of the step 23 and the shape of the wall are not transferred well to the resin substrate 1, and the corner and wall of the step 5 formed on the resin substrate 1 are curved. Thus, the shape corresponding to the shape of the stepped portion 23 is not formed on the resin substrate 1. And when the level difference part 5 is observed with observation apparatuses, such as a microscope, the boundary line of the level difference part 5 can be recognized blurry. Thereby, the inspector can confirm that the transfer is not performed well.

As described above, by observing the shape of the step portion 5 formed on the resin substrate 1, whether or not the shape of the convex portion formed on the molding die 20 has been successfully transferred to the resin substrate 1. Can be evaluated. This makes it possible to evaluate transferability by a simple method without quantitatively measuring the shape of the channel groove.
(Modification)
Next, a microchip according to a modification of the above-described embodiment will be described with reference to FIGS. FIG. 8 is a top view of a resin substrate according to a modification. FIG. 9 is a cross-sectional view of a resin substrate according to a modification, and is a IX-IX cross-sectional view of FIG. In this modification, a resin substrate in which a T-shaped groove is formed by two channel grooves having different depths will be described.

As shown in FIG. 8, the resin substrate 1A is a plate-shaped substrate, and on one surface of the resin substrate 1A, a linear first flow channel groove 2A and a linear second flow channel groove are formed. 3A is formed. In this modification, as an example, the first flow path groove 2A and the second flow path groove 3A are orthogonally formed on the surface of the resin substrate 1A. The second flow path groove 3A is formed halfway through the first flow path groove 2A. As a result, the first channel groove 2A and the second channel groove 3A constitute a T-shaped groove. Since the depth of the second flow path groove 3A is deeper than the depth of the first flow path groove 2A, the intersection of the first flow path groove 2A and the second flow path groove 3A intersects. A step portion 5A is formed on the bottom surface. For example, as shown in FIG. 9, the depth of the first flow path groove 2A is defined as depth d1, and the depth of the second flow path groove 3A is defined as depth d2. Since the depth of the second flow path groove 3A is deeper than the depth of the first flow path groove 2A, the relationship of depth d2> depth d1 is established, and the depth difference δt is the step portion 5A. Of height.

A microchip is manufactured by bonding the resin substrate 1A and the flat resin substrate with the surface on which the first flow channel groove 2A and the second flow channel groove 3A are formed inside. To do. As a result, a fine channel is formed by the first channel groove 2A and the second channel groove 3A.

The dimensions of the resin substrate 1A are the same as the dimensions of the resin substrate 1 according to the above-described embodiment, and the width and depth of the first flow path groove 2A and the second flow path groove 3A are the same as described above. This is the same as the width and depth of the channel groove of the resin substrate 1 according to the embodiment.

As in the above-described embodiment, the resin substrate 1A is manufactured by an injection molding method using a molding die. The molding die is formed with a convex portion corresponding to the first flow channel groove 2A and a convex portion corresponding to the second flow channel groove 3A, and the shape of the convex portion of the molding die is a resin. The resin substrate 1A having the first flow path groove 2A and the second flow path groove 3A is produced. Further, a step portion is provided on the upper surface of the convex portion of the molding die at a position corresponding to the intersecting portion 4A where the first flow path groove 2A and the second flow path groove 3A intersect. Thereby, the level difference of the molding die is transferred to the resin, and the level difference part 5A is formed on the bottom surface of the intersecting part 4A where the first flow path groove 2A and the second flow path groove 3A intersect. By observing the shape of the step portion 5A, the transferability of the first flow path groove 2A and the second flow path groove 3A can be evaluated.

Next, specific examples will be described.

In this example, a resin substrate 1A according to the above-described modification was produced. First, a molding die for producing the resin substrate 1A was produced. Specifically, a molding die having convex portions corresponding to the first channel groove 2A and the second channel groove 3A was produced. Then, by molding PMMA which is a transparent resin material with an injection molding machine using the molding die, the first flow path groove 2A and the second flow path are formed on the surface of a plate-like member having a 30 mm square and a thickness of 1 mm. A resin substrate having a channel groove 3A formed thereon was produced. The dimensions of the groove are shown below.

Depth d1 of first channel groove 2A = 26.5 [μm]
Depth d2 of second channel groove 3A = 26.7 [μm]
The depth δt of the step portion 5A = 0.18 [μm]
Width of first flow path groove 2A = 40.3 [μm]
(Evaluation)
Two resin substrates 1A were produced by molding PMMA, which is a transparent resin material, using an injection molding machine under two different molding conditions, and the transferability of each resin substrate 1A was examined. The appearance of the stepped portion 5A was observed with a general-purpose optical microscope having a magnification of about 400 times, and the difference in the shape of the stepped portion 5A in the resin substrate 1A could be confirmed. In one resin substrate 1A, the step portion 5A was observed to be thick, and in the other resin substrate 1A, the step portion 5A was observed to be thin.

Furthermore, the shape of the two resin substrates 1A was measured with a shape measuring device, and the transferability of the molding was confirmed. It was confirmed that the shape of the resin substrate 1A in which the stepped portion 5A was observed to be thick was largely different from the shape of the molding die, and sufficient molding transfer was not obtained. On the other hand, it was confirmed that the shape of the resin substrate 1A in which the step portion 5A was thinly observed was small in deviation from the shape of the molding die, and sufficient molding transfer was obtained. From the above, the correlation between the observation image by the optical microscope and the molding transferability was confirmed.

The materials and dimensions of the resin substrate shown in the above-described embodiments are for confirming the effects of the present invention, and the present invention is not limited to these. For example, even when the resin mentioned in the above-described embodiment is used, transferability in molding can be evaluated by providing a stepped portion.

Claims

A flow path groove is formed on the surface of at least one of the two resin substrates produced by molding the resin, and the flow path groove is formed on the two resin substrates. A microchip joined with the surface facing inward,
The flow path groove includes a first flow path groove and a second flow path groove intersecting the first flow path groove, and the first flow path groove and the second flow path groove; Is a microchip characterized by different groove depths.
2. The step according to claim 1, wherein a step formed at an intersecting portion where the first channel groove and the second channel groove intersect is used for transferability inspection in molding. Microchip.
The height of the step at the intersection where the first flow path groove and the second flow path groove intersect is determined by the groove depth of the first flow path groove and the groove depth of the second flow path groove. 3. The microchip according to claim 1, wherein the microchip is set in a range of 0.3% to 5% of a deeper groove depth.
Of the at least two resin substrates, at least two flow path grooves are formed on the surface of one resin substrate so as to cross each other, and the plurality of flow path grooves are formed on the two resin substrates. A molding die for molding a resin substrate on which the channel groove of the microchip to be joined with the formed surface inside is formed,
A first protrusion corresponding to one of the intersecting at least two flow path grooves;
The same width as the width of at least one of the two flow path grooves at a position corresponding to the position of the cross section where the at least two flow path grooves intersect on the upper surface of the first convex part. A molding die, wherein the second convex portion is provided with a step having a height.
5. The molding die according to claim 4, wherein the second convex portion is used for inspection of transferability in molding.
The height of the second convex portion is set in a range of 0.3% to 5% of the total height of the first convex portion and the second convex portion. 6. A molding die according to any one of items 4 and 5.
Using each of the plurality of recesses formed by etching so that the plurality of recesses intersect, an electroforming process is performed using an electroforming master in which a step is formed on the bottom surface of the recess at the intersecting intersection. The molding die according to any one of claims 4 to 6, wherein the convex portion corresponding to the concave portion is formed by.