Joint and method for manufacturing the same

Abstract

The purpose of the present invention is to provide: a joined body which is configured so that deformation caused by heating during joining is suppressed, removal of the joined body is facilitated, protein adsorption is suppressed, and low haze can be obtained; and a method for manufacturing the same. This joined body (3) is obtained by joining molded bodies (1) of one or more than one types via a joining layer (2) that has a different material composition than the molded bodies, wherein: the joining layer (2) contains 100 parts by weight of a cyclic olefin resin (4) and a softening agent (5); the amount of the softening agent (5) in the joining layer (2) is 6-99 parts by weight with respect to 100 parts by weight of the cyclic olefin resin (4); and the haze of the joining layer (2) is 1.0 or lower.

Description

[Technical Field]

[0001] This invention relates to a joint and a method for manufacturing the same. [Background technology]

[0002] A method for manufacturing a bonded structure by joining substrates together can be used, for example, to manufacture chips (microfluidic chips) in which micro-channels or reaction vessels on the order of micrometers are formed on the bonding surface of the substrates. Such microfluidic chips can be used in various fields such as the analysis and testing of biomolecules such as DNA, RNA, and proteins, drug discovery and development, organic synthesis, and water quality analysis.

[0003] The resin microfluidic chip is manufactured by bonding a resin substrate, on which fine channels are formed on at least one surface, with a resin lid substrate, which serves as a lid material, by heating and interposing a bonding layer between them (see, for example, Patent Documents 1 to 4). [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Patent No. 5948248 [Patent Document 2] International Publication No. 2014 / 178439 [Patent Document 3] International Publication No. 2011 / 083809 [Patent Document 4] Patent No. 5948248 [Overview of the project] [Problems that the invention aims to solve]

[0005] For example, when manufacturing a composite structure such as a microfluidic chip by joining molded bodies such as substrates via a bonding layer, there is a need to prevent deformation due to heating during bonding, facilitate the re-detachment of the composite structure for recycling and recovery of cells and drugs after testing (reworkability after bonding), suppress protein adsorption to the channels for use in the analysis and testing of biomaterials, and improve the transparency of the bonding layer by reducing the haze of the bonding layer to improve the accuracy of optical signal detection.

[0006] Therefore, the present invention aims to provide a joint and a method for producing the same, which enables the joining of molded articles at relatively low temperatures, thereby suppressing deformation due to heating during joining, facilitating the re-separation of the joint, suppressing protein adsorption, and reducing haze. [Means for solving the problem]

[0007] The inventors of the present invention conducted intensive research to solve the above problems and found that by incorporating a softening agent into the bonding layer, it becomes possible to bond molded bodies at relatively low temperatures, thereby suppressing deformation due to heating during bonding and making it easier to peel the bonded bodies again. Furthermore, by using a specific softening agent, protein adsorption is suppressed and haze is reduced, leading to the completion of the present invention. Thus, the present invention provides the following microfluidic chip and a method for manufacturing the same.

[0008] [1] A bonded body [3] obtained by joining at least one type of molded body [1] via a bonding layer [2] having a different material composition from the molded body, The bonding layer [2] comprises 100 parts by weight of a cyclic olefin resin [4] and a softening agent [5]. The content of the softener [5] in the bonding layer [2] is 6 to 99 parts by weight of the softener [5] per 100 parts by weight of the cyclic olefin resin [4], The haze of the junction layer [2] is 1.0 or less. Zygote [3]. 〔2〕The bonded body [3] according to 〔1〕, wherein the cyclic olefin resin [4] has a number average molecular weight of 12,500 or more. 〔3〕The bonded body [3] according to 〔1〕 or 〔2〕, wherein the cyclic olefin resin [4] has a glass transition temperature of 100°C or lower. 〔4〕The bonded body [3] according to any one of 〔1〕 to 〔3〕, wherein the softening agent [5] is composed of a hydride of liquid paraffin. 〔5〕The bonded body [3] according to any one of 〔1〕 to 〔4〕, wherein the cyclic olefin resin [4] has an alkoxysilyl group. 〔6〕The bonded body [3] according to any one of 〔1〕 to 〔5〕, wherein the molded body [1] is an organic substance, and at least one treatment selected from the group consisting of plasma irradiation, ultraviolet irradiation, corona discharge, and flame spraying is performed on the surface of the molded body [1].

Advantages of the Invention

[0009] According to the present invention, it is possible to provide a bonded body and a method for producing the same, in which deformation due to heating during bonding is suppressed, re-peeling of the bonded body is facilitated, protein adsorption is suppressed, and a low haze is obtained.

Brief Description of the Drawings

[0010] [Figure 1] FIG. 1 shows a conceptual diagram of a method for producing a bonded body of the present invention. [Figure 2] FIG. 2 shows an example of a bonded body of the present invention.

Embodiments for Carrying Out the Invention

[0011] Hereinafter, embodiments of the present invention will be described in detail.

[0012] (Bonded body) The bonded body [3] of the present invention is a bonded body [3] in which at least one or more molded bodies [1] are bonded via a bonding layer [2] having a material composition different from that of the molded body, and the bonding layer [2] has a haze of 1.0 or less. It is characterized in that it has a material composition obtained by blending 6 to 99 parts by weight of a softening agent [5] with respect to 100 parts by weight of a cyclic olefin resin [4], and is a bonded body [3].

[0013] The bonded body [3] of the present invention is used, for example, in a microchannel chip, an inspection container, and a pixel display panel.

[0014] <Molded body> In the present invention, the molded body [1] serves as a substrate. In the present invention, the molded body [1] usually has a flat plate shape. In the bonded body [3], the molded body [1] is usually a pair (two sheets), but may be three or more sheets. When the bonded body [3] is used as a microchannel chip, the molded body [1] may have fine channels formed on at least one surface. The formation of fine channels on the molded body [1] can be carried out using, for example, microfabrication techniques such as photolithography and hot imprinting, cutting, injection molding, and the like.

[0015] Each molded body [1] is made of at least one type of material. That is, each molded body [1] may be made of the same material or different materials. The material of the molded body [1] may be organic or inorganic. Examples of organic materials include cyclic olefin resins, polycarbonate resins, aromatic polyetherketone resins, (meth)acrylic resins, vinyl alicyclic hydrocarbon resins, and aromatic vinyl resins. Here, "(meth)acrylic" means acrylic and / or methacrylic. Examples of inorganic materials include metals (e.g., iron alloys such as stainless steel) and metal oxides (glass, ceramics). When the bonded body [3] is used as a microfluidic chip, from the viewpoint of obtaining a microfluidic chip with excellent durability, with less decrease in bonding strength over time due to moisture absorption and less decrease in optical stability, it is preferable to use a cyclic olefin resin as the substrate resin, and more preferably a cyclic olefin resin with a water absorption rate of 0.01% by mass or less.

[0016] Furthermore, as monomers of cyclic olefin resins used as materials for molded articles [1], norbornene monomers are preferred. Norbornene monomers are monomers containing a norbornene ring. Examples of norbornene monomers include bicyclic monomers such as bicyclo[2.2.1]hept-2-ene (common name: norbornene), 5-ethylidene-bicyclo[2.2.1]hept-2-ene (common name: ethylidenenorbornene), and their derivatives (those having substituents on the ring); tricyclo[5.2.1.0 2,6 Deca-3,8-diene (common name: dicyclopentadiene), and its derivatives, etc., as tricyclic monomers; tetracyclo[7.4.0.0 2,7 .1 10,13 ] Tetradeca-2,4,6,11-tetraene (common name: methanotetrahydrofluorene), tetracyclo[6.2.1.1 3,6 .0 2,7 ] Dodeca-4-ene (common name: tetracyclododecene), 9-ethylidenetetracyclo[6.2.1.1 3,6 .0 2,7Examples include tetracyclic monomers such as dodeca-4-ene and their derivatives; these monomers may have substituents at arbitrary positions. The cyclic olefin resin as the material for the molded article [1] may be an addition polymer, a ring-opening polymer, or a hydride thereof, but it is preferably a ring-opening polymer or a hydride of a ring-opening polymer. The cyclic olefin resin may be amorphous or crystalline, but it is preferably amorphous.

[0017] The ring-opening polymers described above can be produced, for example, by a method using a metathesis reaction catalyst (ring-opening polymerization catalyst) such as the ruthenium carbene complex catalyst described in International Publication No. 2010 / 110323, or by a method using a ring-opening polymerization catalyst such as a tungsten (phenylimide) tetrachloride-tetrahydrofuran complex or tungsten hexachloride described in Japanese Patent Application Publication No. 2015-54885.

[0018] Furthermore, a method for producing alicyclic structure-containing ring-opening polymer hydrides by hydrogenating a ring-opening polymer includes, for example, the method using the hydrogenation catalyst described in International Publication No. 2010 / 110323. Alternatively, for example, the above-mentioned ruthenium carbene complex catalyst can be used as a ring-opening polymerization catalyst to produce an alicyclic structure-containing polymer, and then the ruthenium carbene catalyst can be used as a hydrogenation catalyst to hydrogenate the alicyclic structure-containing ring-opening polymer and produce alicyclic structure-containing ring-opening polymer hydrides.

[0019] The number-average molecular weight of the cyclic olefin resin used as the material for the molded article [1] may be, for example, 5000 or more, preferably 7500 or more, and more preferably 10000 or more. Alternatively, the number-average molecular weight of the cyclic olefin resin may be, for example, 200000 or less, preferably 100000 or less, and more preferably 80000 or less. The molecular weight distribution (Mw / Mn) of the cyclic olefin resin may be, for example, 1.2 or more, preferably 1.5 or more, and more preferably 2.0 or more. Alternatively, the molecular weight distribution (Mw / Mn) of the cyclic olefin resin may be, for example, 6.0 or less, preferably 5.0 or less, and more preferably 4.5 or less.

[0020] The molecular weight (number-average molecular weight Mn) can be measured by gel permeation chromatography (GPC) as described in the examples of this specification and determined as a value equivalent to standard polyisoprene. The molecular weight may also be measured by GPC using cyclohexane as the eluent and determined as a value equivalent to standard polyisoprene. If the sample does not dissolve in cyclohexane, it may be measured by GPC using tetrahydrofuran (THF) as the eluent and determined as a value equivalent to standard polystyrene.

[0021] The glass transition temperature Tg of the cyclic olefin resin used as the material for the molded article [1] is preferably 80°C or higher, and more preferably 100°C or higher. Having a Tg in this range results in good dimensional stability. Furthermore, the glass transition temperature Tg is preferably 170°C or lower, and more preferably 160°C or lower. Having a Tg in this range suppresses oxidation during processing and molding, resulting in less discoloration and yellowing, and a good appearance.

[0022] In this invention, the glass transition temperature can be measured by differential scanning calorimetry (DSC) in accordance with JIS-K7121.

[0023] The glass transition temperature of cyclic olefin resins can be appropriately adjusted depending on the type of monomer used in polymerization, the blending ratio, the average molecular weight, the molecular weight distribution, etc.

[0024] If the molded body [1] is made of organic material, at least one treatment selected from the group consisting of plasma irradiation, ultraviolet irradiation, corona discharge, and flame spraying may be performed on the surface of the molded body [1] (at least the surface on the joining side).

[0025] <Joining layer> The bonding layer [2] is a component for joining molded bodies [1] together and may be formed on at least one of the molded bodies [1]. The bonding layer [2] has a material composition obtained by blending 6 to 99 parts by weight of a softener [5] with 100 parts by weight of a cyclic olefin resin [4] so that the haze is 1.0 or less. The haze of the bonding layer [2] is 1.0 or less, preferably 0.8 or less, and more preferably 0.5 or less. The haze can be measured, for example, by the method described in the examples of this specification (a method using a measuring device such as a haze meter (NDH-7000SP; manufactured by Nippon Denshoku).

[0026] When the conjugate [3] of the present invention is used as a microfluidic chip for the analysis and testing of biomolecules such as DNA, RNA, and proteins, it is preferable that the conjugate layer [2] is made of a material that does not adsorb such biomolecules.

[0027] Examples of cyclic olefin resins [4] used in the bonding layer [2] include those exemplified above as cyclic olefin resins for the molded article [1].

[0028] The cyclic olefin resin [4] may have alkoxysilyl groups. The introduction of alkoxysilyl groups into the cyclic olefin resin [4] can be carried out by graft polymerization or end modification, for example, by impregnating the cyclic olefin resin [4] with an alkoxysilane compound and a peroxide while stirring onto a pellet. Examples of alkoxysilane compounds include trimethoxyvinylsilane, vinyltriethoxysilane, and 3-methacryloxypropyltrimethoxysilane. When the cyclic olefin resin [4] has alkoxysilyl groups, good adhesion can be achieved.

[0029] The number average molecular weight of the cyclic olefin resin [4] is preferably 12,500 or more, more preferably 13,000 or more. Also, the number average molecular weight of the cyclic olefin resin [4] is preferably 200,000 or less, more preferably 100,000 or less, and even more preferably 80,000 or less. When the number average molecular weight of the cyclic olefin resin [4] is within the above range, the fluidity during melt molding and the strength after molding can be made good.

[0030] The glass transition temperature of the cyclic olefin resin [4] is preferably 100°C or less, more preferably 90°C or less, and even more preferably 85°C or less. Also, the glass transition temperature of the cyclic olefin resin [4] is preferably 50°C or more, more preferably 60°C or more, and even more preferably 65°C or more. When the glass transition temperature of the cyclic olefin resin [4] is within the above range, the low-temperature moldability and the shape retention property in the use temperature range can be made good.

[0031] The softening agent [5] is a substance that lowers the softening temperature of the mixed resin. By mixing it with the cyclic olefin resin used in the bonding layer, it is a substance that makes the haze of the mixture 1.0 or less. When the bonded body [3] of the present invention is used as a microchannel chip for analyzing and inspecting biological substances such as DNA, RNA, and proteins, the softening agent [5] is preferably a substance to which such biological substances do not adsorb. Examples of the softening agent [5] include olefin-based low molecular weight substances such as hydrogenated liquid paraffin, polyisobutylene, polybutene, poly-4-methylpentene, poly-1-octene, ethylene-α-olefin copolymer, and their hydrogenated products; conjugated diene-based low molecular weight substances such as polyisoprene, polyisoprene-butadiene copolymer, and their hydrogenated products, etc. Hydrogenated liquid paraffin is preferred. The hydrogenated liquid paraffin preferably has a density of 0.82 to 0.89 g / cm 3 It is preferred that it is so. The kinematic viscosity of the hydrogenated liquid paraffin is 4.0 to 89.0 mm 2It is preferable that the viscosity is / S. The hydride of the liquid paraffin is preferably SUS viscosity of 38 to 420. As the hydride of the liquid paraffin, commercially available products such as Hycol K-350 (manufactured by Kaneda) and Hycol K-140N (manufactured by Kaneda) can be used. By incorporating a softener [5], the glass transition temperature of the bonding layer [2] can be lowered, making it possible to bond molded bodies at a relatively low temperature. This is advantageous because deformation due to heating during bonding is suppressed, and the bonded bodies can be easily peeled off again. Furthermore, by using a hydride of liquid paraffin as the softener [5], protein adsorption to the bonding layer is suppressed, and a low haze is obtained in the bonding layer.

[0032] The thickness of the bonding layer may be, for example, 100 μm or less, preferably 50 μm or less, and more preferably 30 μm or less. The thinner the bonding layer, the thinner the bonding layer becomes, so when used as a microfluidic chip, for example, flow path deformation during steam sterilization is suppressed. The thickness of the bonding layer may also be the minimum thickness that is sufficient to ensure adhesion between the flow path substrate and the lid substrate, for example, 0.1 μm or more, preferably 0.5 μm or more, and more preferably 1.0 μm or more.

[0033] (Method of manufacturing the joint) The joint [3] of the present invention can be manufactured, for example, by the manufacturing method described below (hereinafter referred to as "the manufacturing method of the present invention").

[0034] The manufacturing method of the present invention includes joining molded bodies [1] together by heat fusion via a bonding layer [2]. More specifically, the manufacturing method of the present invention includes the steps of forming a bonding layer [2] on at least one molded body [1], overlapping the molded bodies [1] together via the bonding layer [2] to form a temporary bond, and heating the temporary bond to heat fusion.

[0035] Examples of methods for heat fusion include autoclaves, vacuum plate presses, vacuum diaphragm laminators, and hot roll presses. The heat fusion temperature is preferably 25°C or higher, and more preferably 35°C or higher. Furthermore, the heat fusion temperature is preferably 100°C or lower, and more preferably 60°C or lower. Before heat fusion, it is preferable to remove any trapped air from the temporary joint and then perform the bonding. However, small amounts of air bubbles will be exhausted during processing in a reduced pressure method such as a vacuum plate press, and will diffuse during processing in a pressurized method such as an autoclave, so there is no problem as long as large amounts of air are not trapped.

[0036] If the bonded body [3] of the present invention is a microfluidic chip, the manufacturing method of the present invention may be carried out by first forming a bonding layer [2] over the entire surface of the molded body [1], and then forming a channel on the molded body [1]. That is, the manufacturing method of the present invention may be carried out by the following steps. (1) A step of forming a bonding layer [2] on at least one molded body [1], (2) A step of forming a channel in a molded body [1] having a bonding layer [2] formed on it or a molded body [1] without a bonding layer [2] formed on it by cutting, photolithography, or thermal imprinting. (3) A step of joining a molded body [1] in which a flow channel has been formed and another molded body [1] by heat fusion via a bonding layer [2].

[0037] Alternatively, if the bonded body [3] of the present invention is a microfluidic chip, the manufacturing method of the present invention may be carried out by first creating a molded body [1] in which channels are formed, and then forming a bonding layer [2] on the surface of the molded body [1] other than the portion corresponding to the channels. That is, the manufacturing method of the present invention may be carried out by the following steps. (1) A step of forming a molded body [1] in which a flow channel has been formed, (2) A step of forming a bonding layer [2] on the surface of a molded body [1] in which a flow channel is formed or on a portion of the surface of a molded body [1] in which no flow channel is formed, other than the portion corresponding to the flow channel. (3) A step of joining molded bodies [1] together by heat fusion via a bonding layer [2], wherein at least one of the molded bodies [1] has a flow channel formed in it, and at least one of the molded bodies [1] has a bonding layer [2] formed in it.

[0038] In the jointed body [3] of the present invention, if the molded body [1] is an organic material other than a cyclic olefin resin such as polycarbonate or acrylic, the manufacturing method of the present invention may further include performing at least one treatment selected from the group consisting of plasma irradiation, ultraviolet irradiation, corona discharge, and flame spraying on the surface of the molded body [1].

[0039] (Re-detachment of the joint) The bonded body [3] of the present invention may be peeled back for recycling, for example. Peeling back the bonded body [3] can be performed, for example, by leaving the bonded body [3] in an oven heated to a temperature at which the bonding layer softens for a predetermined time, or by heating the bonded body [3] with a dryer or the like. [Examples]

[0040] The present invention will be described in detail below based on examples, but the present invention is not limited to these examples.

[0041] <Methods for measuring and evaluating physical properties> The measurement and evaluation of various physical properties were performed according to the following methods.

[0042] (Method for measuring the number-average molecular weight Mn) The number-average molecular weight (Mn) was measured by gel permeation chromatography (GPC) using cyclohexane as the eluent and determined as a value equivalent to standard polyisoprene. Standard polyisoprene manufactured by Tosoh Corporation was used as the standard polyisoprene. If the sample did not dissolve in cyclohexane, it was measured by GPC using tetrahydrofuran (THF) as the eluent and determined as a value equivalent to standard polystyrene. Standard polystyrene manufactured by Tosoh Corporation was used as the standard polystyrene.

[0043] (Method for Measuring Glass Transition Temperature) The glass transition temperature (Tg) was measured using a differential scanning calorimeter (manufactured by Nanotechnology Co., Ltd., product name: DSC6220SII) based on JIS-K7121 under the condition of a heating rate of 10 °C / min.

[0044] [1. Production of Cyclic Olefin Polymer (COP)] [Production of COP-Tg156] (1-1) Production of Ring-Opening Polymer: Into a glass reaction vessel with the interior replaced by nitrogen, 200 parts by weight of dehydrated cyclohexane, 0.75 mol% of 1-hexene, 0.15 mol% of diisopropyl ether, and 0.44 mol% of triisobutylaluminum were placed in the reactor at room temperature and mixed with respect to a total of 100 parts by weight of the monomers described below. Then, while maintaining the temperature at 45 °C, 40 parts by weight of methanotetrahydrofluorene (MTF), 56 parts by weight of tetracyclododecene (TCD), and 4 parts by weight of dicyclopentadiene (DCPD) as monomers, and 0.02 mol% of tungsten hexachloride (0.65 wt% toluene solution) were continuously added in parallel over 2 hours and polymerized. Next, 0.2 mol% of isopropyl alcohol was added to the polymerization solution to inactivate the polymerization catalyst and stop the polymerization reaction. In the above description, the amounts indicated in the unit “mol%” are all values based on a total monomer amount of 100 mol%. The number average molecular weight (Mn) of the obtained norbornene-based ring-opening polymer was 1.33x10 4 , the weight average molecular weight (Mw) was 2.8×10 4 , and the molecular weight distribution (Mw / Mn) was 2.1. Also, the conversion rate of the monomers to the polymer was 100%.

[0045] (1-2) Production of Norbornene-Based Cyclic Olefin Polymer (COP-Tg156) by Hydrogenation: Next, 300 parts of the reaction solution containing the ring-opening polymer obtained in the above step (1-1) was transferred to an autoclave equipped with a stirrer, and 3 parts of a diatomaceous earth-supported nickel catalyst (manufactured by JGC Chemical Co., Ltd., “T8400RL”, nickel loading rate 57%) was added, and a hydrogenation reaction was carried out at a hydrogen pressure of 4.5 MPa and 160 °C for 4 hours.

[0046] After the hydrogenation reaction, the obtained solution was subjected to pressure filtration at a pressure of 0.25 MPa using Radiolite #500 as a filter bed (a "Hundaback filter" manufactured by Ishikawajima-Harima Heavy Industries Co., Ltd.) to remove the hydrogenation catalyst, and a colorless and transparent solution was obtained. The obtained solution was poured into a large amount of isopropanol to precipitate a norbornene-based cyclic olefin polymer (COP-Tg156) as a hydride of the ring-opening polymer. After filtering the precipitated norbornene-based cyclic olefin polymer (COP-Tg156), it was dried in a vacuum dryer (220 °C, 1 Torr) for 6 hours to obtain a norbornene-based cyclic olefin polymer (COP-Tg156). The number average molecular weight (Mn) of the norbornene-based cyclic olefin polymer (COP-Tg156) was 1.52×10 4 and the weight average molecular weight (Mw) was 3.5×10 4 , and the molecular weight distribution Mw / Mn was 2.3.

[0047] The glass transition temperature Tg of the obtained norbornene-based cyclic olefin polymer (COP-Tg156) was 156 °C.

[0048] The norbornene-based cyclic olefin polymer (COP-Tg156) obtained in the above step (1-2) was charged into a twin-screw extruder and formed into a strand-shaped molded body by hot melt extrusion molding. This molded body was shredded using a strand cutter to obtain pellets of a thermoplastic norbornene-based resin containing the norbornene-based cyclic olefin polymer (COP-Tg156).

[0049] <Production of COP-Tg68 (Twin-screw kneading reaction)> Except that 31 parts by weight of tetracyclododecene (TCD), 33 parts by weight of dicyclopentadiene (DCPD), and 36 parts by weight of norbornene (NB) were used as monomers, the production of COP-Tg156 was carried out in the same manner to obtain a norbornene-based cyclic olefin polymer (COP-Tg68) and pellets of a thermoplastic norbornene-based resin containing COP-Tg68. The number average molecular weight (Mn) of COP-Tg68 was 13,000, and the glass transition temperature Tg was 68 °C.

[0050] <Production of Silane-Modified COP-Tg68> With respect to 100 parts by weight of the thermoplastic norbornene resin containing COP-Tg68, 2 parts by weight of trimethoxyvinylsilane (KBM-1003; manufactured by Shin-Etsu Silicone) and 0.1 part by weight of peroxide (Perhexa 25B; manufactured by NOF Corporation) were weighed, and while stirring in a Henschel mixer (Super Mixer SMV manufactured by Kawata), they were attached to the pellets. The COP-Tg68 resin with external lubrication was charged into the metering hopper of a twin-screw kneader (TEM-37B; manufactured by Shibaura Machine), and melt kneading was performed at a screw barrel temperature of 220°C, a screw rotation speed of 150 rpm, and a residence time of 90 seconds. The taken-out strand was cooled in a water tank and pelletized with a pelletizer (Fan Cutter; manufactured by Hoshi Plastic) to prepare silane-modified COP-Tg68 (hereinafter referred to as "Si-COP-Tg68"). The number average molecular weight (Mn) of Si-COP-Tg68 was 12,700, and the glass transition temperature Tg was 65°C.

[0051] <Production of COP-Tg138> Except that 27 parts by weight of methanotetrahydrophenalene (MTF), 35 parts by weight of tetracyclododecene (TCD), and 38 parts by weight of dicyclopentadiene (DCPD) were used as monomers, in the same manner as the production of COP-Tg156, pellets of a norbornene-based cyclic olefin polymer (COP-Tg138) and a thermoplastic norbornene resin containing COP-Tg138 were obtained. The number average molecular weight (Mn) of COP-Tg138 was 13,000, and the glass transition temperature Tg was 138°C.

[0052] [2. Production of Substrate Molded Body] <Production of Substrate Molded Body by Injection Molding> The pellets of COP-Tg156 resin were dried at Tg - 20°C for 5 hours. Thereafter, by a conventional method, the pellets were injection molded using an injection molding machine (FANUC ROBOSHOT (registered trademark) α100B, manufactured by Fanuc) at a resin temperature of Tg + 150°C, a mold temperature of Tg - 10°C, and a holding pressure of 80 MPa to obtain a substrate molded body (hereinafter referred to as "injection molded body") in the form of a flat plate of 100 mm × 100 mm × 2 mm.

[0053] <Manufacturing of base material molded products by sheet molding> COP-Tg156 resin was fed into the hopper of a single-screw extruder (single-layer extruder; manufactured by GSI Crios) equipped with a T-die, extruded at a barrel temperature of 260°C and a screw rotation speed of 80 rpm, and wound up while being cooled and fixed with a mirror-finished cooling roll to obtain a base material molded body (hereinafter referred to as "sheet molded body") with a thickness of 125 μm.

[0054] <Base material molded body made of stainless steel> SUS304 (manufactured by Nippon Metal Co., Ltd.) was used as the stainless steel material. The stainless steel material was cut into flat plates of 100 mm x 100 mm x 2 mm to obtain a base molded body.

[0055] <Base material molded from corona discharge polycarbonate resin> As a corona discharge polycarbonate resin, one side of Panlite PC-2151#125 (manufactured by Teijin Corporation) was subjected to corona discharge treatment to obtain a corona discharge polycarbonate resin. The corona discharge polycarbonate resin was cut into flat sheets of 100 mm x 100 mm x 2 mm to obtain a base material molded body.

[0056] [3. Formation of the bonding layer on the release film] For every 100 parts by weight of resin, a predetermined amount of softening agent was weighed out, and the total amount was considered the solid content. 20 parts by weight of this solid content was then mixed with 80 parts by weight of cyclohexane (special grade: manufactured by Wako Pure Chemical Industries) in sealed glass containers (Pyrex® medium bottles: manufactured by Corning), and dissolved by shaking at 60°C to prepare a cyclohexane solution with a solid content concentration of 20 parts by weight per 100 parts by weight of solution. The obtained solution was cast onto the silicon side of a 50μ silicone-coated PET film (separator SP-PET; manufactured by Mitsui Chemicals Tohcello) fixed on a glass plate, and wet coating was performed using an applicator with a 300μm gap (doctor blade film applicator; manufactured by Allgood Co., Ltd.). The coated film was dried at room temperature for about 10 minutes, and then heated and dried in an 80°C oven for 1 hour to obtain a bonded layer coated film in which a 30μm thick bonded layer was formed on the 50μ silicone-coated PET film (release film).

[0057] [4. Bonding of molded substrates via a bonding layer] A sheet molded body (125 μm thick x 26 mm x 76 mm) and a bonding layer coating film (80 μm thick x 26 mm x 76 mm) were cut to the respective dimensions onto a molded plate (3 mm thick x 26 mm x 76 mm). The bonding layer coating film was placed on top of the cut molded plate with the bonding layer side facing outwards and aligned. After alignment, the pieces were pressed several times with a rubber roll to remove trapped air and bond them together. After bonding, only the silicone-coated PET (release film) was peeled off to create a temporary bond A with the bonding layer on the molded plate. The 125 μm thick sheet molded body was placed on top of this temporary bond A, ensuring that it did not shift position, and pressed several times with a rubber roll to remove air bubbles and create a temporary bond B. Note that small amounts of air bubbles will diffuse during autoclave processing, so there is no problem as long as large amounts of air are not trapped. The temporary joint B was inserted into a retort pouch (manufactured by Meiwa Pax) and degassed using a vacuum packaging machine (TECHNOVAC T1000; manufactured by Nippon Packaging Machinery). This degassed package was placed in an autoclave container (Tandelion DL-2010; manufactured by Hanyuda Iron Works) and bonded and defoamed at 30°C, 0.5 MPa, and for 15 minutes, to obtain the joint.

[0058] [5. Rating] <Adhesive strength> Subsequently, the strength was measured in accordance with JIS K 6854-2 (180° peel). A cut with a width of 10 mm was made through the sheet molding body and the bonding layer on the sheet molding body side of the bonded body as shown in Figure 2. The 10-mm-wide portion where the cut was made from the end was exposed so that it could be chuck-fixed. The injection molding body side was fixed to the lower chuck of a universal testing machine with an oven (Autograph AGS-X10kN; manufactured by Shimadzu Corporation), and the sheet molding body side was fixed to the upper chuck. The temperature of the oven was set to 38°C, and after the temperature inside the oven stabilized at 38°C ± 1, it was held for 5 minutes. After holding, 180° peeling was performed at a peeling width of 10 mm and a peeling speed of 100 mm / min to obtain the peeling strength, which was taken as the adhesive strength. Similarly, for the measurement at 80°C, only the temperature of the oven was changed, and other operations were carried out in the same manner.

[0059] <Haze> The bonding layer coating film was cut to the same dimensions as a 28-mm × 48-mm microslide glass (S3132; manufactured by Matsunami Glass Industries Co., Ltd.), and it was overlapped with the adhesive surface facing up on the microslide glass for alignment. After alignment, it was pressed several times with a rubber roll to remove the trapped air and perform crimping. After crimping, only the silicon-coated PET was peeled off, and a microslide glass (S3132; manufactured by Matsunami Glass Industries Co., Ltd.) of the same dimensions was overlapped on the peeled bonding layer surface for alignment. After alignment, crimping was performed while removing the trapped air with a rubber roll to obtain a temporarily bonded body C. The temporarily bonded body C was inserted into a bag for retort pouches (manufactured by Meiwa Pax), and degassing packaging was performed with a vacuum packaging machine (TECHNOVAC T1000; manufactured by Nippon Packing Machine Co., Ltd.). This degassed package was placed in an autoclave container (Tanderion DL-2010; manufactured by Haneda Iron Works Co., Ltd.), and bonding and defoaming treatments were performed at 30°C, 0.5 MPa, and a heating and pressurizing time of 15 minutes to obtain a bonded body for haze measurement. The obtained bonded body for haze measurement was subjected to haze measurement with a haze meter (NDH-7000SP; manufactured by Nippon Denshoku Industries Co., Ltd.). At that time, the haze measurement value of the microslide glass alone was less than 0.1, and the value obtained by subtracting this value as a blank was taken as the haze.

[0060] <BSA adsorption amount> As a protein adsorption test, the amount of fetal bovine serum albumin (BSA) adsorbed onto the conjugate layer was measured using the following method (micro-BCA method).

[0061] (1. Preparation of adhesive solution) For every 100 parts by weight of resin, a predetermined amount of softening agent was weighed out, and the total amount was considered the solid content. To this 20 parts by weight of solid content, 80 parts by weight of cyclohexane (special grade: manufactured by Wako Pure Chemical Industries) were sealed in glass airtight containers (Pyrex® medium bottles: manufactured by Corning) and dissolved by shaking under heating at 60°C to prepare a cyclohexane solution with a solid content of 20 parts by weight.

[0062] (2. Preparation of the adsorbed sample) To prepare a 35mm Petri dish (Nunc Petri Dish 150460; manufactured by Term Fisher), 1 mL of the cyclohexane solution prepared in step 1 above was added to each 35mm dish, spreading it evenly over the entire bottom surface of the dish. After drying at room temperature for about 10 minutes, the dish was heated and dried in an 80°C oven for 1 hour to create an adhesive-coated dish.

[0063] (3. Protein adsorption treatment and extraction) A BSA solution adjusted to 1 mg / mL with phosphate buffer was placed in a 2.5 mL adhesive-coated dish and incubated in a 37°C incubator for 2 hours to adsorb the BSA. The sample was removed from the incubator, the BSA solution was extracted, and the dish was washed with PBS solution. Next, a 2.5 mL 1 wt% sodium dodecyl sulfate (SDS) solution was placed in a dish and treated with an ultrasonic cleaner for 5 minutes to extract the solution.

[0064] (4. Protein quantification) For calibration purposes, 150 μL each of BSA solutions ranging from 20 mg / mL to a blank (PBS only) were placed in a 96-well plate, and 150 μL of the extract obtained in step 3 above was placed in the plate for measurement. Next, using a micro-BCA kit (micro-BCA assay kit; Thermo Fisher), 150 μL of the kit reagent was added to each 96-well plate, and the mixture was gently stirred with a plate shaker for about 30 seconds. To prevent evaporation, the 96-well plate was sealed, and the reaction was incubated in a 37°C incubator for 2 hours. After the reaction, the absorbance at 562 nm was measured using a plate reader, and the amount of protein adsorbed was calculated from the calibration curve.

[0065] <curve> The process was the same as described in [4. Bonding of base material molded bodies via a bonding layer] above, but with the dimensions changed from injection molded body (3mm thick x 15mm x 100mm) to sheet molded body (125μm thick x 15mm x 100mm) and bonding layer coating film (80μm thick x 15mm x 76mm), and was prepared in the same manner. The warping was measured by placing the bonded parts, which had been bonded in an autoclave, onto a horizontal surface such as a glass plate, and measuring the amount of lift at both ends with calipers.

[0066] [7. Results] The manufacturing conditions and the results of each evaluation are shown in Table 1.

[0067] [Table 1-1]

[0068] [Table 1-2] [Industrial applicability]

[0069] According to the present invention, it is possible to provide a joint in which deformation due to heating during joining is suppressed, the joint can be easily re-detached, protein adsorption is suppressed, and low haze is obtained, as well as a method for producing the same.

Claims

1. A microfluidic chip [3] is formed by joining at least one type of molded body [1] via a bonding layer [2] having a different material composition from the molded body, The bonding layer [2] comprises 100 parts by weight of a cyclic olefin resin [4] and a hydride of liquid paraffin [5]. The content of the liquid paraffin hydride [5] in the bonding layer [2] is 6 to 99 parts by weight of liquid paraffin hydride [5] per 100 parts by weight of cyclic olefin resin [4]. The haze of the bonding layer [2] is 1.0 or less. The cyclic olefin resin [4] has a glass transition temperature of 100°C or less. Microfluidic chip [3].

2. The microfluidic chip [3] according to claim 1, characterized in that the cyclic olefin resin [4] has a number average molecular weight of 12,500 or more.

3. The microfluidic chip [3] according to claim 1 or 2, characterized in that the cyclic olefin resin [4] has an alkoxysilyl group.

4. A microfluidic chip [3] according to any one of claims 1 to 3, characterized in that the molded body [1] is an organic material, and at least one treatment selected from the group consisting of plasma irradiation, ultraviolet irradiation, corona discharge, and flame blowing is performed on the surface of the molded body [1].

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