The present invention relates to a molding die, a microchip, and a manufacturing apparatus of the microchip.
Conventionally, there has been practically used microchips (also referred to as micro analysis chips or micro fluid chips) or an apparatus called μTAS (Micro Total Analysis Systems) using the microchips, wherein a fine flow fluid passage or a circuit is formed on a silicon or glass substrate by using fine processing technology to conduct chemical reactions, separation, and analysis of a nucleic acid, a protein, and a liquid sample such as blood in a minute space. Such a microchip reduces the amounts of samples and reagents to be used and the discharge amount of waste fluid, thereby achieving a space-saving, portable, and inexpensive system.
A microchip is manufactured by attaching two members to each other, at least one of which is finely processed. Recently, a resin micro chip has been proposed to facilitate low-cost production. More specifically, the resin microchip is manufactured by bonding a resin substrate having a fluid passage groove on the surface to a resin cover (e.g., a film) for covering the fluid passage groove. Through holes are formed at the ends of the fluid passage groove on the substrate across the thickness direction, for example. The substrate having the fluid passage groove on the surface is bonded to the cover with the fluid passage groove inside. The bonding allows the cover to function as a lid for the fluid passage groove, and thus the fluid passage groove and the cover form a fluid passage. Thereby, a microchip including a fluid passage inside is manufactured. The through holes formed in the substrate link the fluid passage to the exterior of the microchip, thereby allowing the introduction and discharge of a liquid specimen via the through holes.
The resin substrate is manufactured by molding a melted resin.
With reference to
Regarding such resin molding, various techniques for preventing the generation of flashes B during resin molding have been recently developed to reduce the effect of the flashes B formed on the peripheries of a molded product (for example, refer to Patent Documents 1 to 4).
Patent Document 1: Japanese Patent Application Laid Open Publication No. 2009-126151
Patent Document 2: Japanese Patent Application Laid Open No. 2001-079887
Patent Document 3: Japanese Patent Application Laid Open No. 2001-038759
Patent Document 4: Japanese Patent Application Laid Open No. H10-315254
The cutting of the gate molded portion 106 in the direction toward the film bonding surface, as described above, forms a nub or a burr 108 of the resin on the cut surface adjacent to the film bonding surface and/or a swell or a bulge 109 of the resin on the remaining part of the gate molded portion 106 adjacent to the first die 100, as illustrated in
The present invention has been conceived in light of the circumstances described above and an object of the present invention is to provide a molding die, a microchip, and a manufacturing apparatus of the microchip that can reduce adverse effects caused by burrs and bulges.
In order to solve the above problem, according to the present invention, there is provided a molding die for molding a substrate to be included in a microchip, wherein the microchip is formed by forming a fluid passage groove on one surface of the substrate and attaching a cover to the one surface, the molding die includes a first die and a second die contactable with and separable from the first die, a molding space for molding the substrate and a gate for introducing resin into the molding space are formed between the first die and the second die, a molding surface of the first die includes a first-die substrate molding region which molds the one surface of the substrate, a gate-defining region which defines the gate, and a rising region which is located between the gate-defining region and the first-die substrate molding region and extends from an edge of the first-die substrate molding region toward the second die, and the gate-defining region is closer to the second die than the first-die substrate molding region.
According to the present invention, a rising region rises from the edge of the first-die substrate molding region toward the second die between the first-die substrate molding region and the gate-defining region, and the gate-defining region is disposed closer to the second die than the first-die substrate molding region. Thus, the gate molded portion (portion of the resin cured in the gate) is disposed further inward than the one surface (surface joined with the cover) when the molded product is viewed from the first die. Thus, a burr and/or a bulge formed as a result of cutting off the gate molded portion in the direction from the second die to the first die can be positioned closer to the other surface than the one surface. Such positions of the burr and the bulge can reduce the adverse effects of the burr and the bulge.
[
[
[
[
[
[
[
[
[
[
[
[
[
[
[
[
[
[
[
Embodiments of the present invention will now be described with reference to the drawings. The present invention, however, should not be limited to the embodiments. In the drawings, the same or equivalent elements will be designated by the same reference numerals, without redundant descriptions.
(1. Inspection Apparatus)
An inspection apparatus according to the embodiment will now be described with reference to
As illustrated in
As illustrated in
(1-1. Fluid Delivering Unit)
The fluid delivering unit 14 delivers fluid to/from the microchip 2 and is connected to the microchip 2, which is conveyed into the inspection apparatus 1 through the conveying slit 11. The fluid delivering unit 14 includes at least one micropump 140, a chip connection section 141, a driving liquid tank 142, an driving liquid supply section 143 and such like.
The fluid delivering unit 14 is provided with one or more micropumps 140 performing fluid delivery to and from the microchip 2 by injecting driving liquid 146 into the microchip 2 and sucking fluid, such as an assay sample, from the microchip 2. If a plurality of micropumps 140 are provided, the micropumps 140 can be driven independently or in conjunction with each other. If a medium, an analyte, a reagent, and other fluid are injected into the microchip in advance, fluid delivery by driving liquid is not always necessary and otherwise only the micropump may be operated to support the transfer of the medium. Alternatively, the micropump may be used exclusively for injection of a reagent and an analyte.
The micropump 140 is in communication with the microchip 2 via the chip connection section 141.
The driving liquid tank 142 retains the driving liquid 146 while supplying the driving liquid 146 to the driving liquid supply section 143. The driving liquid tank 142 is detachable from the driving liquid supply section 143 for refill of the driving liquid 146.
The driving liquid supply section 143 supplies the driving liquid 146 from the driving liquid tank 142 to the micropump 140.
As described above, in the fluid delivering unit 14, the microchip 2 is in communication with the micropump 140 via the chip connection section 141. The micropump 140 is driven to inject/suck the driving liquid 146 to/from the microchip 2 via the chip connection section 141. The analyte, the reagent and such like that are stored in multiple storage sections in the microchip 2 are delivered through the microchip 2 by the driving liquid 146. As a result, the analyte and the reagent are mixed in the microchip 2 to trigger a reaction for detection of a target substance or the diagnosis of a disease, for example.
(1-2. Heating Unit)
The heating unit 15 generates thermal energy to heat the microchip 2 to several specific temperatures. For example, the heating unit 15 heats the microchip 2 to a thermal denaturation temperature of approximately 95 μC, an annealing temperature of approximately 55 μC, and a polymerizing temperature of approximately 70 μC. Such heating facilitates gene amplification through PCR method. The heating unit 15 is configured by including an element that generates heat with electricity, such as a heater or a Peltier element, an element that lowers the temperature through water conduction, and such like.
(1-3. Voltage Application Unit)
The voltage application unit 18 includes a plurality of electrodes. The electrodes are disposed in the liquid sample in the microchip 2 and directly apply a voltage to the liquid sample or are placed in contact with current-carrying portions 40, which are described below, and apply a voltage to the liquid sample via the after-mentioned current-carrying portions 40 for electrophoresis of the liquid sample in the microchip 2.
(1-4. Detection Unit)
The detection unit 16 includes a light source such as light-emitting diode (LED) or laser beams and a light-receiving unit such as photodiode (PD), and optically detects a target substance contained in the fluid generated through a reaction in the microchip 2 in a predetermined area (detection area 200, which is described below) on the microchip 2. The light source and the light-receiving unit are positioned in a transmission arrangement or a reflection arrangement, whichever is more desirable.
(1-5. Drive Controller)
The drive controller 17 includes a microcomputer and a memory (not shown in the drawings), and drives, controls and detects the components in the inspection apparatus 1.
(2. Microchip)
The microchip 2 according to this embodiment will now be described with reference to
With reference to
The substrate 3 is provided with fluid passage grooves 30 on the surface bonded to the film 4 (which hereinafter is referred to as “inner side surface 3A”). The fluid passage grooves 30 on the substrate 3 define micro fluid passages 20 in cooperation with the film 4 attached to the substrate 3. The micro fluid passages 20 include a detection area 200 in which the detection unit 16 of the inspection apparatus 1 detects a target substance. The micro fluid passages 20 (fluid passage grooves 30) having a width and depth within a preferred range of 10 to 200 μm require only small volumes of analytical samples and reagents and lead to excellent precision, transferability, and releasability of the mold; however, the micro fluid passages 20 can have any other width and depth. The width and depth of the micro fluid passages 20 may be selected in accordance with the usage of the microchip. The cross-section of the micro fluid passages 20 may be rectangular or rounded.
The substrate 3 has a plurality of through holes 31 in the thickness direction. These through holes 31 are formed at the ends and intermediate portions of the fluid passage grooves 30. The substrate 3 joined with the film 4 defines openings 21 through which the micro fluid passages 20 are in communication with the exterior of the microchip 2. The openings 21 are connected to the chip connection section 141 (tubes or nozzles) of the fluid delivering unit 14 of the inspection apparatus 1 to introduce/discharge a gel or liquid sample or a buffer solution to/from the micro fluid passages 20. Electrodes of the voltage application unit 18 of the inspection apparatus 1 can be disposed in the openings 21. The openings 21 (through holes 31) may have a circular, rectangular, or any other shape. As illustrated in
The film 4 corresponds to the cover according to the present invention and is formed in a sheet in this embodiment. Micro fluid passages and holes may also be formed on the film 4. The film 4, however, should not be excessively thick to ensure bonding with the substrate 3. Depending on the type of analyte, reagent or inspection, electrophoresis of the sample may be conducted in the micro fluid passages 20 by disposing the electrodes of the voltage application unit 18 in the openings 21 (through holes 31) and applying a voltage.
The openings 21 may be positioned and shaped as illustrated in
The substrate 3 and the film 4 may have any external shape that facilitates handling and analysis. The preferred shape in a plan view is a square or a rectangle. Each side is, for example, within the range of 10 to 200 mm. Alternatively, the side may be within the range of 10 to 100 mm. The substrate 3 having the fluid passage grooves 30 has a thickness in the range of preferably 0.2 to 5 mm, more preferably 0.5 to 2 mm to achieve excellent moldability. The film 4 serving as a lid (cover) covering the fluid passage grooves has a thickness within the range of preferably 30 to 300 m, more preferably 50 to 150 μm.
The substrate 3 and the film 4 are formed of resin. The resin of the substrate 3 and the film 4 should have excellent moldability (transferability and releasability), excellent transparency, and low autofluorescence to ultraviolet and visible rays. The substrate 3 and the film 4 are formed of, for example, thermoplastic resin. Preferred thermoplastic resins include polycarbonates, polymethyl methacrylate, polystyrene, polyacrylonitrile, polyvinyl chloride, polyethylene terephthalate, nylon 6, nylon 66, polyvinyl acetate, polyvinylidene chloride, polypropylene, polyisoprene, polyethylene, polydimethylsiloxane, cyclic polyolefins and such like. The resins particularly preferred are polycarbonates, polymethyl methacrylate and cyclic polyolefins. The substrate 3 and the film 4 may be formed of the same material or different materials. The substrate 3 and the film 4 made of the same material will have high compatibility, promoting bonding after melting.
The substrate 3 and the film 4 are joined together by heat bonding. For example, the substrate 3 and the film 4 are joined by heating with a heated plate, hot air, a hot roller, ultrasonic sound, vibration, or a laser beam. For example, the substrate 3 and the film 4 are disposed between heated plates of a hot press and pressed between the heated plates for a predetermined time to be bonded to each other. The pressed film 4 serves as a lid (cover) of the fluid passage grooves 30, and the fluid passage grooves 30 and the film 4 define the micro fluid passages 20 of the microchip 2. Heat bonding of the substrate 3 and the film 4 is only required at the interface of the substrate 3 and the film 4. Ultrasonic waves, vibration or a laser beam can heat only the interface.
(3. Manufacturing Apparatus of Microchip)
The manufacturing apparatus of a microchip 2 will now be described.
The manufacturing apparatus of the microchip 2 joins the substrate 3 with the film 4 which are preliminarily prepared to form a microchip 2. The apparatus includes a molding unit 5 for preparing the substrate 3, such as that illustrated in
The molding unit 5 includes a fixed platen 51 disposed on a base 50 and a movable platen 52.
The fixed platen 51 is a flat plate vertically disposed on the base 50. Columnar tie bars 53 are disposed at the four corners of the fixed platen 51 such that the tie bars 53 extend orthogonal to the fixed platen 51.
The movable platen 52 is a flat plate disposed parallel to the fixed platen 51 and is supported by the tie bars 53 disposed at the four corners of the fixed platen 51. The movable platen 52 is guided along the tie bars 53 with a driving mechanism (not shown in the drawings) in the horizontal direction (in the directions indicated by arrows A and Ab in the drawing), i.e., toward or away from the fixed platen 51.
A molding die 6 is disposed between the fixed platen 51 and the movable platen 52. The movement of the movable platen 52 in the direction indicated by arrow A causes clamping of the molding die 6, whereas the movement of the movable platen 52 in the direction indicated by arrow Ab causes opening of the molding die 6.
(3-1. Molding Die)
With reference to the drawing, the molding die 6 is an injection mold configured by including a fixed die 60 as a first die and a movable die 61 as a second die which moves toward or away from the fixed die 60. The fixed die 60 and the movable die 61 contact with each other to form a molding space 64 for molding melted resin J into the shape of the substrate 3. A runner 62 and a gate 63 for introducing the melted resin J to the molding space 64 are formed between the fixed die 60 and the movable die 61. The runner 62 is connected to an injection unit via a sprue (not shown in the drawings). The molding space 64 is filled with the melted resin J from the runner 62 through the gate 63.
The fixed die 60 shapes a portion of the inner side surface 3A (surface adjacent to the film 4) of the substrate 3 and is fixed to the fixed platen 51.
The fixed die 60 has a fixed-die molding surface 605. The drawing illustrates an imaginary view of a film 4 to be joined with the substrate 3 after molding. The thickness of the film 4 is exaggerated for illustrative purposes. The thickness of the film 4 is exaggerated in the same way in
The fixed-die molding surface 605 includes a fixed-die substrate molding region 606, a gate-defining region 607, and a rising region 608. The fixed-die substrate molding region 606 shapes the inner side surface 3A of the substrate 3 and, in this embodiment, extends along the same plane as a parting line PL of the molding space 64.
The gate-defining region 607 corresponds to a portion of the fixed die 60 defining the gate 63 and shapes the resin 103 cured in the gate 63 (hereinafter referred to as “gate molded portion G”) adjacent to the fixed die 60.
The rising region 608 is disposed between the gate-defining region 607 and the fixed-die substrate molding region 606 and extends from the edge of the fixed-die substrate molding region 606 toward the movable die 61 to shape a portion of the peripheral side surface of the substrate 3. The gate-defining region 607 is disposed closer to the movable die 61 than the fixed-die substrate molding region 606.
In this embodiment, the fixed die 60 includes an annular peripheral piece 600 and a columnar central piece 601 fit inside the peripheral piece 600. The gate-defining region 607 is provided on the peripheral piece 600, while the fixed-die substrate molding region 606 is provided on the central piece 601. The rising region 608 is provided along a portion (adjacent to the gate 63) of the circumference of the interface between the peripheral piece 600 and the central piece 601.
The movable die 61 shapes the outer side surface 3B (remote from the inner side surface 3A) of the substrate 3 and is fixed to the movable platen 52.
The movable die 61 includes an annular peripheral piece 610 and a columnar central piece 611 which is fitted inside the peripheral piece 610.
The peripheral piece 610 shapes the peripheral portion of the outer side surface 3B of the substrate 3 and the peripheral side surface of the substrate 3, while the central piece 611 shapes the center portion of the outer side surface 3B. The movable die 61 has an ejection pin (not shown in the drawings) that is ejectable from the molding surface to release the molded product from the movable die 61.
By the fixed die 60 and the movable die 61 consisting of a central piece and a peripheral piece, only the central piece including the microstructures such as the micro fluid passages can be replaced. This reduces costs of the entire mold and readily allows modifications in the fluid passage structure.
In the molding die 6, flashes B of approximately 20 m are formed, for example, on the contacting portion between the fixed die 60 and the movable die 61 and on the contacting portion between the peripheral piece 600 and the central piece 601 in the fixed die 60.
(3-2. Manufacturing Method of Substrate)
A manufacturing method of the substrate 3 with the molding die 6 will now be described.
The melted resin J is injected to the molding space 64 from the runner 62 through the gate 63 and is molded under pressure inside the molding space 64.
When the molded product is cooled to a specific temperature, the movable die 61 is separated from the fixed die 60, and the molded product is released from the fixed die 60.
The ejection pin is ejected from the movable die 61 to release the molded product from the movable die 61.
The gate molded portion G is cut off from the molded product to acquire the substrate 3.
According to the embodiment, the rising region 608 extends from the edge of the fixed-die substrate molding region 606 toward the movable die 61 between the fixed-die substrate molding region 606 and the gate-defining region 607 of the fixed-die molding surface 605, and the gate-defining region 607 is disposed closer to the movable die 61 than the fixed-die substrate molding region 606. Thus, the gate molded portion G is disposed further inward than the inner side surface 3A when the molded product is viewed from the inner side surface 3A, as illustrated in
The second embodiment of the present invention will now be described with reference to
With reference to the drawing, the molding die 6A includes a fixed die 60A and a movable die 61A, alternative to the fixed die 60 and the movable die 61 according to the embodiment described above.
A fixed-die molding surface 605A in the fixed die 60A includes a rising region 608A, alternative to the rising region 608 according to the embodiment described above.
The rising region 608A surrounds the fixed-die substrate molding region 606 and shapes the entire peripheral side surface of a portion of the substrate 3 adjacent to the inner side surface 3A.
A movable-die molding surface 615A of the movable die 61A includes a movable-die substrate molding region 616A and a rising region 609.
The movable-die substrate molding region 616A shapes the outer side surface 3B of the substrate 3.
The rising region 609 extends from the edge of the movable-die substrate molding region 616A toward the fixed die 60 and shapes the entire peripheral side surface of a portion of the substrate 3 adjacent to the outer side surface 3B. A parting line PL of the molding space 64 of the molding die 6A according to this embodiment runs between the movable-die substrate molding region 616A and the fixed-die substrate molding region 606A.
In this embodiment, the movable-die substrate molding region 616A straddles the central piece 611 and the inner circumferential portion of the peripheral piece 610, while the rising region 609 is provided on the peripheral piece 610. Depressions in the peripheral piece 610 of the movable die 61 shape the runner 62 and the gate 63.
A film 4, which is indicated by the dotted lines in the drawing, is bonded to the area inside the peripheral portion of the inner side surface 3A of the substrate 3 which is shaped by the molding die 6A.
As described above, the same advantageous effects as those of the first embodiment are achieved in this embodiment. In addition, since the parting line PL of the molding space 64 runs between the movable-die substrate molding region 616A and the fixed-die substrate molding region 606A, the rising regions 608A and 609, which shape the peripheral side surface of the substrate, surround the peripheral portions of the movable-die substrate molding region 616A and the fixed-die substrate molding region 606A. The fixed die 60 is configured by including the central piece 601, which includes the fixed-die substrate molding region 606, and the peripheral piece 600, which surrounds the fixed-die substrate molding region 606. A gap can be readily formed between the central piece 601 and the peripheral piece 600, which are joined together in the thickness direction of the substrate 3, promoting the formation of a flash B on the peripheral portion of the inner side surface 3A of the substrate 3 rising in a direction orthogonal to the inner side surface 3A.
With respect to this, according to the embodiment, the film 4 is attached to the substrate 3 on an area inside the peripheral portion of the inner side surface 3A. Thus, the microchip 2 can be manufactured without involving the flash B of the peripheral portion in the bonding of the film 4 and the substrate 3.
In the second embodiment, the depressions in the peripheral piece 610 of the movable die 61 shape the runner 62 and the gate 63. Alternatively, as illustrated in
The third embodiment of the present invention will now be described with reference to
With reference to the drawing, the molding die 6B includes a fixed die 60B and a movable die 61B, alternative to the fixed die 60 and the movable die 61 in the embodiment described above.
A movable-die molding surface 615B of the movable die 61B has a movable-die substrate molding region 616B.
The movable-die substrate molding region 616B shapes the outer side surface 3B of the substrate 3. Specifically, the movable-die substrate molding region 616B shapes a depression or a protrusion (hereinafter referred to as “depression/protrusion T”) on the outer side surface 3B of the substrate 3. Referring to
A fixed-die molding surface 605B of the fixed die 60B has a rising region 608B, alternative to the rising region 608 according to the embodiment described above.
The rising region 608B surrounds the fixed-die substrate molding region 606 and shapes the entire peripheral side surface of the substrate 3 along the thickness direction. The parting line PL of the molding space 64 of the molding die 6B in the embodiment and the movable-die substrate molding region 616B are disposed on a single plane.
A film 4, which is indicated by the dotted lines in the drawing, is bonded to the substrate 3 shaped by the molding die 6B in the area inside the peripheral portion of the inner side surface 3A.
As described above, the same advantageous effects as those of the first embodiment are achieved in the embodiment. In addition, since the parting line PL of the molding space 64 and the movable-die substrate molding region 616B are disposed on a single plane, the rising region 608B, which shapes the peripheral side surface of the substrate 3, surrounds the peripheral portion of the fixed-die substrate molding region 606. The fixed die 60 is configured by including the central piece 601, which includes the fixed-die substrate molding region 606, and the peripheral piece 600, which surrounds the fixed-die substrate molding region 606. Thus, a gap can be readily formed between the central piece 601 and the peripheral piece 600, which are joined together in the thickness direction of the substrate 3, promoting the formation of a flash B on the peripheral portion of the inner side surface 3A of the substrate 3 in a direction orthogonal to the inner side surface 3A.
According to the embodiment, the film 4 is attached to the substrate 3 on an area inside the peripheral portion of the inner side surface 3A. Thus, the microchip 2 can be manufactured without involving the flash B of the peripheral portion in the bonding of the film 4 and the substrate 3.
The movable-die substrate molding region 616B shapes the depression/protrusion T on the outer side surface 3B of the substrate 3. Thus, even in a case where the substrate 3 is fit in the fixed die 60 for molding, the frictional resistance (demolding resistance) between the molded product and the movable die 61 is increased to facilitate the release of the molded product from the fixed die 60.
The present invention is not limited to the embodiments described above, and various modifications of the embodiments may be employed within the scope of the invention.
The entire disclosure of Japanese Patent Application No. 2010-243668, filed on Oct. 29, 2010, including Description, Claims, Drawings, and Abstract is herein incorporated in its entirety.
As described above, the present invention is suitable for a molding die, a microchip, and a manufacturing apparatus of the microchip that can reduce the adverse effects of flashes and bulges.
2 microchip
3 substrate
4 film (cover)
6, 6A, 6B molding die
3A inner side surface (one surface)
3B outer side surface (the other surface)
60 fixed die (first die)
61 movable die (second die)
63 gate
64 molding space
606 fixed-die substrate molding region
607 gate-defining region
608, 608A, 608B rising region
616A, 616B movable-die substrate molding region
PL parting line
T depression/protrusion (depression or protrusion)
Number | Date | Country | Kind |
---|---|---|---|
2010-243668 | Oct 2010 | JP | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/JP2011/074479 | 10/25/2011 | WO | 00 | 4/29/2013 |