Analytical cover film, analytical component, and analytical method

Abstract

The present invention provides an analytical cover film, analytical component, and analytical method that can suppress the leakage of the analyte. [Solution] An analytical cover film 1 to be attached to an analytical substrate 2 having a containment section 4 for containing a fluid to be analyzed and a planar adhesive attachment section 3 adjacent to the containment section 4, comprising a base film 10 and an adhesive layer 20 laminated on one side of the base film 10, wherein the arithmetic mean roughness Ra of the side of the adhesive layer 20 that is attached to the analytical substrate 2 is 500 nm or less.

Description

Technical Field

[0001] The present invention relates to an analysis member used for analyzing an analyte that is a fluid, an analysis cover film used for the analysis member, and an analysis method using the analysis member.

Background Art

[0002] There are methods for optically analyzing a sample for the purpose of measuring the turbidity in a sample such as a liquid or measuring a specific component amount in the sample. In such an optical analysis method, light is irradiated onto the sample, and the light generated thereby is measured. More specific examples of such an analysis method include a method of irradiating light onto a sample and measuring the degree of scattering of the light, a method of irradiating light onto a sample and measuring the amount of light absorbed by components in the sample when the light passes through the sample, a method of measuring fluorescence generated in the sample, and the like. In such an analysis method, conventionally, a sample was accommodated in a test tube or cell having a volume of several milliliters.

[0003] In recent years, an analysis method using an analysis member provided with a fine flow path for accommodating a sample has been developed instead of the above-mentioned test tube or cell. In such a method, even a small amount of sample can be analyzed, so that the amount of sample required for analysis can be very small. Furthermore, by using an analysis member having a plurality of grooves, intensive measurement can be performed, so that a large number of samples can be analyzed simultaneously.

[0004] As an example of the above-mentioned analysis member having a fine flow path, Patent Document 1 discloses a multilayer composite structure including a base material constituting the side surface of the groove, a first layer constituting the bottom surface of the groove, and a resealable film serving as a cover for covering the groove (paragraph 0032 and FIG. 2 of Patent Document 1). Further, Patent Document 2 discloses a plastic microchip formed by bonding a plastic substrate having the above-mentioned groove as a fine flow path on the surface and a plastic film serving as a cover for covering the groove via an adhesive (Claim 1 and paragraph 0019 of Patent Document 2).

Prior Art Documents

[0005] [Patent Document 1] Special Publication No. 2006-510384 [Patent Document 2] Japanese Patent Publication No. 2008-157644 [Overview of the project] [Problems that the invention aims to solve]

[0006] Incidentally, as is also the case with the analytical members described in Patent Documents 1 and 2, the grooves may be covered with a film having an adhesive layer in order to prevent evaporation, leakage, and contamination of the sample.

[0007] However, depending on the condition of the adhesive layer, the adhesion between the grooved substrate and the film may not be sufficient, causing the liquid sample contained in the grooves to seep out between the substrate and the adhesive layer. Such seepage can lead to an excessive reduction in the amount of sample to be analyzed, or, if there are multiple grooves, contamination may occur.

[0008] This invention has been made in view of the above-described circumstances, and aims to provide an analytical cover film, an analytical member, and an analytical method that can suppress the leakage of the analyte. [Means for solving the problem]

[0009] To achieve the above objective, firstly, the present invention provides an analytical cover film to be attached to an analytical substrate having a containment portion for containing a fluid to be analyzed and a planar adhesive attachment portion adjacent to the containment portion, wherein the analytical cover film comprises a base film and an adhesive layer laminated on one side of the base film, and the arithmetic mean roughness Ra of the side of the adhesive layer attached to the analytical substrate is 500 nm or less (Invention 1).

[0010] In the analytical cover film according to the above invention (Invention 1), having the above-mentioned arithmetic mean roughness Ra results in a smooth adhesive surface of the adhesive layer, allowing it to adhere closely to the planar adhesive surface adjacent to the containment portion. Therefore, gaps are less likely to occur between the adhesive layer and the adhesive surface at the boundary between the containment portion and the adhesive surface, and consequently, the leakage of fluid contained in the containment portion between the adhesive layer and the adhesive surface is effectively suppressed.

[0011] In the above invention (Invention 1), it is preferable that the housing portion is a groove having an opening (Invention 2).

[0012] In the above inventions (Inventions 1 and 2), it is preferable that the adhesive layer is laminated on the base film so that it can face the accommodating portion and the adhesive application portion of the analytical substrate (Invention 3).

[0013] In the above inventions (Inventions 1 to 3), it is preferable that the adhesive layer is an adhesive layer made of a pressure-sensitive adhesive or a thermoplastic resin layer (Invention 4).

[0014] In the above inventions (Inventions 1 to 4), it is also preferable that the adhesive layer is a pressure-sensitive adhesive layer, and that the thickness of the adhesive layer is 0.3 μm or more and 500 μm or less (Invention 5).

[0015] In the above inventions (Inventions 1 to 4), it is also preferable that the adhesive layer is a thermoplastic resin layer, and the thickness of the thermoplastic resin layer is greater than 4 μm and 500 μm or less (Invention 6).

[0016] In the above inventions (Inventions 1 to 6), it is preferable that a hard coat layer is formed on the surface of the substrate opposite to the adhesive layer (Invention 7).

[0017] Second, the present invention provides an analysis member including a housing portion for housing a fluid as an analysis target, an analysis substrate having a planar adhesive application portion adjacent to the housing portion, and the analysis cover film (Inventions 1 to 7) adhered to the analysis substrate, wherein a flow path is formed by sealing an opening of the housing portion with the analysis cover film (Invention 8).

[0018] Third, the present invention provides an analysis method, which comprises preparing the analysis member (Invention 8), housing a fluid as an analysis target in the flow path of the analysis member, and analyzing the analysis target in the flow path (Invention 9).

Advantages of the Invention

[0019] According to the analysis cover film, analysis member, and analysis method of the present invention, leakage of the analysis target can be suppressed.

Brief Description of the Drawings

[0020] [Figure 1] FIG. 1 is a cross-sectional view of an analysis cover film according to an embodiment of the present invention. [Figure 2] FIG. 2 is a cross-sectional view of an analysis member according to an embodiment of the present invention.

Modes for Carrying Out the Invention

[0021] Hereinafter, embodiments of the present invention will be described. Note that the term "analysis" in this specification is also intended to include the concept of "inspection".

[0022] 〔Analysis Cover Film〕 FIG. 1 shows an analysis cover film 1 according to an embodiment of the present invention. The analysis cover film 1 includes a base film 10 and an adhesive layer 20 laminated on one side of the base film 10. In the analysis cover film 1 according to the present embodiment, the adhesive layer 20 constitutes the outermost layer on one side of the analysis cover film 1.

[0023] The analytical cover film 1 according to this embodiment is for constructing an analytical member used for analysis, and preferably for constructing an analytical member 100 as shown in Figure 2. The analytical member 100 comprises an analytical substrate 2 and an analytical cover film 1 attached to the analytical substrate 2. The analytical substrate 2 has a groove 4 which is a containment part for containing a fluid as the object to be analyzed (for example, a sample), and a planar adhesive attachment part 3 adjacent to the groove 4. In this embodiment, the adhesive layer 20 of the analytical cover film 1 is laminated on the base film 10 so as to face the groove 4 and the adhesive attachment part 3. The analytical cover film 1 is fixed to the analytical substrate 2 by the adhesive layer 20 of the analytical cover film 1 being attached to the adhesive attachment part 3. The groove 4 of the analytical substrate 2 has its opening (the upper surface of the groove 4 in Figure 2) sealed by the analytical cover film 1, thereby forming a flow path. In this analytical member 100, analysis is performed on the object to be analyzed contained in the groove 4.

[0024] In the analytical cover film 1 according to this embodiment, the arithmetic mean roughness Ra of the side of the adhesive layer 20 that is attached to the analytical substrate 2 (adhesive surface) is 500 nm or less. As a result, the adhesive surface of the adhesive layer 20 becomes smooth and adheres closely to the planar adhesive adherend portion 3 adjacent to the groove 4. Therefore, gaps are less likely to occur between the adhesive layer 20 and the adhesive adherend portion 3 at the boundary between the groove 4 and the adhesive adherend portion 3, and thus, the leakage of fluid contained in the groove 4 between the adhesive layer 20 and the adhesive adherend portion 3 is effectively suppressed.

[0025] From the viewpoint of suppressing the above-mentioned seepage, the arithmetic mean roughness Ra is preferably 300 nm or less, more preferably 150 nm or less, particularly preferably 70 nm or less, and even more preferably 30 nm or less. The lower limit of the arithmetic mean roughness Ra is not particularly limited, but is usually preferably 0.5 nm or more, particularly preferably 1 nm or more, and even more preferably 3 nm or more. The method for measuring the arithmetic mean roughness Ra of the adhesive surface of the adhesive layer in this specification is as shown in the test examples described later.

[0026] In the analytical cover film 1 according to this embodiment, the adhesive layer 20 is laminated on the base film 10 so as to face the grooves 4 and adhesive adherends 3 of the analytical substrate 2, and in this embodiment in particular, it is laminated over the entire surface of one side of the base film 10. Therefore, when manufacturing the analytical cover film 1, there is no need for processes or means such as removing the formed adhesive layer 20 in accordance with the grooves 4 or not forming the adhesive layer 20 in accordance with the grooves 4, and the analytical cover film 1 can be manufactured easily and at low cost by the casting method described later.

[0027] Furthermore, if an adhesive layer 20 is not provided in the portion of the analytical cover film 1 facing the groove 4, it must be considered that the fluid contained in the groove 4 may seep out between the edge of the adhesive layer 20 near the groove 4 and the base film 10, or be absorbed into the interior of the adhesive layer 20 from its edge. However, with the analytical cover film 1 having the above configuration, such a need is eliminated.

[0028] Furthermore, if the adhesive layer 20 is a thermoplastic resin layer, the unevenness of the adhesive surface may deform when heated and bonded, reducing the arithmetic mean roughness Ra and potentially suppressing fluid seepage. However, as in the above configuration, if the adhesive layer 20 is laminated on the base film 10 so as to face the groove 4 of the analysis substrate 2, if the heating temperature and pressure during bonding are high, the thermoplastic resin may enter the groove 4, and the flow path may not be formed to the intended size. Therefore, the heat and pressure during bonding must be controlled to mild conditions, in which case the deformation of the unevenness of the adhesive surface as described above will be small, and the change in the arithmetic mean roughness Ra will also be small. Accordingly, in the analysis cover film 1 according to this embodiment, the arithmetic mean roughness Ra of the adhesive surface of the adhesive layer 20 is set to be small as described above at the stage before bonding.

[0029] Analytical methods for the analytical member 100 using the analytical cover film 1 according to this embodiment include, for example, optical analysis such as optical detection of the target substance by irradiation with laser light or LED light, and fluorescence detection of the target substance, as well as analysis and separation of substances by polymerase chain reaction (PCR) and electrophoresis. In this specification, the light used in the analysis may be referred to as "analytical light." Details of analytical light will be described later. Below, optical analysis will be mainly described as an analytical method, but the present invention is not limited thereto.

[0030] 1. Components of the analytical cover film 1-1. Base film The base film 10 in this embodiment can be any film that can perform the desired analysis well. For example, when performing optical analysis, it is preferable that the film be transparent to analytical light, and in particular, it is preferable that it be optically isotropic.

[0031] The base film 10 can be made of resin, glass, or the like, but resin is preferred because it is easy to manufacture and handle. In other words, the base film 10 is preferably a resin film.

[0032] Examples of the above-mentioned resins include polyesters such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; polyolefins such as polyethylene and polypropylene; polycarbonate, cycloolefin copolymer, diacetylcellulose, triacetylcellulose, acetylcellulose butyrate, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, ethylene-vinyl acetate copolymer, polystyrene, polymethylpentene, polysulfone, polyetheretherketone, polyethersulfone, polyetherimide, polyimide, polyamide, acrylic resin, norbornene-based resin, fluororesin, polyphenylene sulfide, and liquid crystal polymer. Resin films using these resins may be single layers or laminates of the same or different types of resins.

[0033] The above-mentioned resin film is preferably an unstretched film from the viewpoint of optical isotropy. Furthermore, among resin films, it is preferable to use a polycarbonate film, a cycloolefin copolymer film, a polyethylene terephthalate film, a polybutylene terephthalate film, or an acrylic resin film from the viewpoint of excellent transmittance to analytical light, and in particular, it is preferable to use a cycloolefin copolymer film or a polycarbonate film.

[0034] Furthermore, it is preferable that the material of the base film 10 is the same as the material of the analytical substrate 2, which will be described later. By using the same material, the difference in transmittance to analytical light between the base film 10 and the analytical substrate 2 can be reduced, and the influence of such differences on the measurement can be reduced.

[0035] The glass transition temperature (Tg) of the material constituting the base film 10 is preferably 100°C or higher, particularly preferably 120°C or higher, and even more preferably 140°C or higher. This makes it difficult for the base film 10 to melt even if the analytical member 100 is heated during analysis, effectively suppressing deformation of the base film 10 and effectively suppressing peeling and shifting at the interface between the base film 10 and the adhesive layer 20. Although there is no particular upper limit to the glass transition temperature (Tg) of the material constituting the base film 10, from the viewpoint of flexibility for attaching the analytical cover film 1, it is usually preferably 300°C or lower, particularly preferably 250°C or lower, and even more preferably 200°C or lower.

[0036] In the base film 10, it is preferable to form a hard coat layer on the side opposite to the adhesive layer 20. This improves the smoothness of the side of the base film 10 opposite to the adhesive layer 20 and also prevents scratches on that side, allowing for more accurate analysis, especially optical analysis. In particular, the formation of a hard coat layer is effective for cycloolefin copolymer films and polycarbonate films, as their surfaces are easily scratched.

[0037] The hard coat layer can be formed from known materials, and its thickness is not particularly limited and can be of a general thickness. For example, active energy ray curable components such as polyfunctional acrylate monomers and acrylate prepolymers can be used as materials. The thickness can be, for example, about 0.5 to 20 μm.

[0038] In the base film 10, surface treatments such as oxidation or embossing, or primer treatments, can be applied to the surface facing the adhesive layer 20 in order to improve adhesion with the adhesive layer 20. Examples of oxidation methods include corona discharge treatment, plasma discharge treatment, chromium oxidation treatment (wet), flame treatment, hot air treatment, ozone treatment, and ultraviolet irradiation treatment. Examples of embossing methods include sandblasting and thermal spraying. These surface treatment methods are appropriately selected depending on the type of material constituting the base film 10. Among these, oxidation or primer treatment is preferred from the viewpoint of maintaining the smoothness of the base film 10.

[0039] The thickness of the base film 10 is preferably 30 μm or more, particularly preferably 50 μm or more, even more preferably 75 μm or more, and most preferably 90 μm or more. This ensures that the base film 10 has sufficient strength, is easy to handle, and suppresses deformation and damage to the base film 10 when using the analytical member 100. Furthermore, the thickness is preferably 300 μm or less, particularly preferably 200 μm or less, even more preferably 150 μm or less, and most preferably 110 μm or less. This makes it easier to perform good analysis with the resulting analytical member 100. In particular, in optical analysis, the base film 10 tends to have excellent transmittance to analytical light.

[0040] The transmittance of analytical light through the base film 10 is preferably 60% or higher, particularly preferably 80% or higher, and even more preferably 90% or higher. This allows the analytical cover film 1 to have better transmittance to analytical light, enabling more accurate analysis. The upper limit of the above transmittance is not particularly limited, but is 100% or less.

[0041] The arithmetic mean roughness Ra of the surface of the base film 10 opposite to the adhesive layer 20 is preferably 200 nm or less, particularly preferably 100 nm or less, and even more preferably 50 nm or less. This effectively reduces the scattering of analytical light in the base film 10, enabling more accurate optical analysis. The lower limit of the arithmetic mean roughness Ra is not particularly limited, but is usually preferably 0.1 nm or more, particularly preferably 0.5 nm or more, and even more preferably 1 nm or more.

[0042] The arithmetic mean roughness Ra of the surface of the base film 10 opposite to the adhesive layer 20 can be obtained by fixing the analytical cover film 1 to the glass plate via double-sided tape so that the adhesive layer 20 side of the analytical cover film 1 faces the glass plate, and then measuring the surface of the analytical cover film 1 facing the base film 10 using a surface roughness measuring instrument (Mitutoyo Corporation, product name "rSV-3000S4", stylus type) in accordance with JIS B0601:2013.

[0043] 1-2.Adhesive layer The adhesive layer 20 of the analytical cover film 1 according to this embodiment is not particularly limited, as long as it can securely fix the analytical cover film 1 and the analytical substrate 2, the arithmetic mean roughness Ra of the side attached to the analytical substrate 2 (adhesive surface) can satisfy the aforementioned value, and it does not adversely affect the analysis.

[0044] The adhesive is preferably a pressure-sensitive adhesive (tack) or a thermoplastic resin. These adhesives offer excellent handling and adhesion to the analytical substrate 2, while minimizing adverse effects on the grooves 4 during and after application. When the adhesive is a pressure-sensitive adhesive, the adhesive layer 20 becomes a tack layer; when the adhesive is a thermoplastic resin, the adhesive layer 20 becomes a thermoplastic resin layer.

[0045] 1-2-1. Adhesive layer This section describes the case where the adhesive layer 20 is an adhesive layer made of a pressure-sensitive adhesive (tack).

[0046] The adhesive constituting the adhesive layer 20 may be any adhesive that satisfies the above conditions, and its type is not particularly limited. For example, it may be any of the following: acrylic adhesive, polyester adhesive, polyurethane adhesive, rubber adhesive, silicone adhesive, etc. Furthermore, the adhesive may be of emulsion type, solvent type, or solvent-free type, and may be of crosslinked type or non-crosslinked type, but a crosslinked type is preferred as it is easier to obtain cohesiveness of the adhesive layer. Among these, an acrylic adhesive is preferred as it has excellent adhesive properties, optical properties, etc. As for acrylic adhesives, a crosslinked type is preferred, and a thermally crosslinked type is even more preferred. Furthermore, the adhesive in this embodiment may be non-curable by active energy rays or curable by active energy rays.

[0047] The adhesive constituting the adhesive layer 20 is preferably obtained from an adhesive composition (hereinafter sometimes referred to as "adhesive composition P"), and more specifically, it is preferably obtained from an adhesive composition P containing a polymer (A). Furthermore, if the adhesive constituting the adhesive layer is of the crosslinking type, an adhesive layer obtained from an adhesive composition P containing a polymer (A) and a crosslinking agent (B) is preferred, and the adhesive composition P may optionally contain an active energy ray curable component (C). Note that the concept of "polymer" also includes the concept of "polymer".

[0048] (1) Each component (1-1) Polymer (A) Examples of polymer (A) include (meth)acrylic acid ester polymers, polyolefins, polyurethanes, and rubber-based polymers, but (meth)acrylic acid ester polymer (A1) is preferred from the viewpoint of easily adjusting various physical properties. In this specification, (meth)acrylic acid means both acrylic acid and methacrylic acid. The same applies to other similar terms. (Meth)acrylic acid ester polymer (A1) preferably contains a component derived from alkyl (meth)acrylate ester. This allows for the expression of good tackiness. The alkyl group may be linear or branched.

[0049] From the viewpoint of adhesiveness, alkyl (meth)acrylate esters with 1 to 20 carbon atoms in the alkyl group are preferred, and from the viewpoint of further improving adhesiveness, alkyl (meth)acrylate esters with 4 to 8 carbon atoms in the alkyl group are preferred. Examples of alkyl (meth)acrylate esters with 4 to 8 carbon atoms in the alkyl group include n-butyl (meth)acrylate, n-pentyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and isooctyl (meth)acrylate. Among these, n-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, or isooctyl (meth)acrylate are particularly preferred. These may be used individually or in combination of two or more.

[0050] The (meth)acrylic acid ester polymer (A1) preferably contains a component derived from a reactive group-containing monomer that has a reactive group within its molecule that reacts with the crosslinking agent (B). The reactive group derived from this reactive group-containing monomer reacts with the crosslinking agent (B) to form a crosslinked structure (three-dimensional network structure), resulting in an adhesive with the desired cohesive force.

[0051] Preferred reactive group-containing monomers include monomers having a hydroxyl group in the molecule (hydroxyl group-containing monomers) and monomers having a carboxyl group in the molecule (carboxyl group-containing monomers). Reactive group-containing monomers can be used individually or in combination of two or more. Among these, hydroxyl group-containing monomers or carboxyl group-containing monomers that exhibit excellent reactivity with the crosslinking agent (B) are preferred, and using both in combination is also preferable.

[0052] As the hydroxyl group-containing monomer, hydroxyalkyl (meth)acrylate esters having a hydroxyalkyl group with 1 to 4 carbon atoms are preferred from the viewpoint of reactivity with the crosslinking agent (B) and copolymerizability with other monomers. Examples include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate. These may be used individually or in combination of two or more.

[0053] Examples of carboxyl group-containing monomers include ethylenically unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, and citraconic acid. Among these, acrylic acid is preferred in terms of the reactivity of the carboxyl group in the resulting (meth)acrylic acid ester polymer (A1) with the crosslinking agent (B) and copolymerizability with other monomers. These may be used individually or in combination of two or more.

[0054] The (meth)acrylic acid ester polymer (A1) preferably contains 0.5 to 20% by mass of a component derived from a reactive group-containing monomer, and more preferably 1 to 10% by mass. This results in the formation of a good crosslinking structure in the resulting adhesive, and a suitable cohesive force is obtained.

[0055] The (meth)acrylic acid ester polymer (A1) may optionally contain components derived from other monomers. Examples of other monomers include alicyclic monomers such as isobornyl (meth)acrylate, nitrogen atom-containing monomers such as N-(meth)acryloylmorpholine, alkoxyalkyl (meth)acrylates such as methoxyethyl (meth)acrylate and ethoxyethyl (meth)acrylate, vinyl acetate, and styrene. These may be used individually or in combination of two or more.

[0056] The (meth)acrylic acid ester polymer (A1) is preferably a linear polymer. Being a linear polymer makes it easier for molecular chains to intertwine, which can be expected to improve cohesiveness.

[0057] The (meth)acrylic acid ester polymer (A1) may be polymerized in solution, without solvents, or in emulsion.

[0058] The polymerization mode of the (meth)acrylic acid ester polymer (A1) may be a random copolymer or a block copolymer.

[0059] The weight-average molecular weight of the (meth)acrylic acid ester polymer (A1) is preferably 10 to 3 million, and more preferably 300,000 to 2.5 million. This tends to result in a suitable adhesive strength for the resulting adhesive. Here, the weight-average molecular weight as used herein is the value on a standard polystyrene basis measured by gel permeation chromatography (GPC).

[0060] In the adhesive composition P, the (meth)acrylic acid ester polymer (A1) may be used alone or in combination of two or more types.

[0061] (1-2) Crosslinking agent (B) The crosslinking agent (B) can be any agent that can react with the reactive groups of the polymer (A). Examples of crosslinking agents (B) include isocyanate crosslinking agents, epoxy crosslinking agents, amine crosslinking agents, melamine crosslinking agents, aziridine crosslinking agents, hydrazine crosslinking agents, aldehyde crosslinking agents, oxazoline crosslinking agents, metal alkoxide crosslinking agents, metal chelate crosslinking agents, metal salt crosslinking agents, and ammonium salt crosslinking agents. The crosslinking agent (B) can be used alone or in combination of two or more types.

[0062] When polymer (A) has a hydroxyl group as a reactive group, it is preferable to use an isocyanate-based crosslinking agent that has high reactivity with the hydroxyl group. When polymer (A) has a carboxyl group as a reactive group, it is preferable to use an epoxy-based crosslinking agent or an isocyanate-based crosslinking agent that has high reactivity with the carboxyl group. Isocyanate-based crosslinking agents and epoxy-based crosslinking agents can also be used in combination.

[0063] When the adhesive composition P contains a crosslinking agent (B), the amount of the crosslinking agent (B) is preferably 0.05 to 10 parts by mass, and more preferably 0.1 to 8 parts by mass, per 100 parts by mass of the (meth)acrylic acid ester polymer (A1). This makes it easier to obtain an adhesive with desirable cohesive force and tackiness.

[0064] (1-3) Active energy ray curing component (C) The adhesive composition P may also preferably contain an active energy ray curable component (C). This results in an adhesive that is active energy ray curable, hardens upon irradiation with active energy rays, and exhibits excellent cohesiveness. This makes it difficult for the adhesive layer to penetrate the grooves of the analytical substrate, thus preventing a reduction in the cross-sectional area of ​​the flow path.

[0065] The active energy ray curable component (C) is not particularly limited as long as it hardens upon irradiation with active energy rays, and is preferably a compound having functional groups that can react with each other by active energy rays, such as vinyl groups, (meth)acryloyl groups, epoxy groups, and oxetanyl groups. The active energy ray curable component (C) may be a monomer, oligomer, or polymer, or a mixture thereof, or the polymer (A) described above may have the property of hardening upon irradiation with active energy rays and also serve as the active energy ray curable component (C). Among these, polyfunctional acrylate monomers or polyfunctional acrylate oligomers are particularly preferred.

[0066] As the polyfunctional acrylate monomer, 1- to 6-functional acrylate monomers are preferred, and 2- to 3-functional acrylate monomers are more preferred. Examples of 2- to 3-functional acrylate monomers include ethylene oxide-modified isocyanuric acid diacrylate, ethylene oxide-modified isocyanuric acid triacrylate, and dicyclopentanyl di(meth)acrylate. These may be used individually or in combination of two or more. Furthermore, from the viewpoint of compatibility with other compounding materials such as polymer (A), polyfunctional acrylate monomers with a molecular weight of less than 1000 are preferred.

[0067] Examples of polyfunctional acrylate oligomers include epoxy (meth)acrylate and urethane (meth)acrylate, and their molecular weight is usually 1000 or more.

[0068] When the adhesive composition P contains a polymer (A) and an active energy ray curable component (C), that is, when the adhesive composition P contains an active energy ray curable component (C) separately from the polymer (A), the content of the active energy ray curable component (C) in the adhesive composition P is preferably 3 to 100 parts by mass, and particularly preferably 5 to 50 parts by mass, per 100 parts by mass of polymer (A), from the viewpoint of improving the adhesive strength of the resulting adhesive.

[0069] (1-4) Photopolymerization initiator (D) When the adhesive composition P contains an active energy ray-curable component (C) and ultraviolet light is used as the active energy ray, it is preferable to include a photopolymerization initiator (D). By including a photopolymerization initiator (D), the active energy ray-curable component (C) can be cured efficiently, and the polymerization curing time and the amount of ultraviolet light irradiation can be reduced. As such a photopolymerization initiator (D), photoradical polymerization initiators, photocationic polymerization initiators, photoanionic polymerization initiators, etc., can be used.

[0070] If the adhesive composition P contains a photopolymerization initiator (D), the amount of the photopolymerization initiator (D) is preferably 2 to 20 parts by mass, particularly preferably 4 to 18 parts by mass, and even more preferably 6 to 15 parts by mass, per 100 parts by mass of the active energy ray curable component (C).

[0071] (1-5) Diluted solvent Adhesive composition P may contain a diluent. Examples of diluent solvents include aliphatic hydrocarbons such as hexane, heptane, and cyclohexane; aromatic hydrocarbons such as toluene and xylene; halogenated hydrocarbons such as methylene chloride and ethylene chloride; alcohols such as methanol, ethanol, propanol, butanol, and 1-methoxy-2-propanol; ketones such as acetone, methyl ethyl ketone, 2-pentanone, isophorone, and cyclohexanone; esters such as ethyl acetate and butyl acetate; and cellosolve solvents such as ethyl cellosolve. Adhesive composition P may also be a solvent-free composition that does not contain a diluent.

[0072] (1-6) Active energy ray curable monomer (C1) When the adhesive composition P contains an active energy ray curable component (C) and is solvent-free, it is preferable that the adhesive composition P contains an active energy ray curable monomer (C1) as the active energy ray curable component (C). This makes it possible to reduce the viscosity of the adhesive composition P (or its coating solution) during application, allowing for smooth application and making it easier to control the arithmetic mean roughness Ra of the adhesive surface of the adhesive layer (the adhesive surface of the adhesive layer 20) to the aforementioned value. It is preferable that the active energy ray curable monomer (C1) be used in combination with other active energy ray curable components (C), such as an active energy ray curable oligomer or an active energy ray curable polymer.

[0073] As the active energy ray curable monomer (C1), for example, an acrylic monomer (C11) can be used. The acrylic monomer (C11) may be a monofunctional acrylic monomer having one (meth)acryloyl group or a polyfunctional acrylic monomer having two or more (meth)acryloyl groups, but from the viewpoint of adjusting the crosslinking density in the molecular structure formed in the adhesive layer, a monofunctional acrylic monomer is preferred.

[0074] Examples of acrylic monomers (C11) include alkyl (meth)acrylates having 1 to 20 carbon atoms in the alkyl group. The alkyl group may be linear, branched, or partially or entirely cyclic. Examples of alkyl (meth)acrylates having 1 to 20 carbon atoms in the alkyl group include isooctyl (meth)acrylate, n-decyl (meth)acrylate, n-dodecyl ((meth)acrylate) (lauryl (meth)acrylate), and isobornyl acrylate. In addition, (meth)acrylate esters having functional groups other than alkyl groups may be used, such as carboxyethyl acrylate, phenoxyethyl acrylate, and phenoxyethylene glycol acrylate. These may be used individually or in combination of two or more. Among the above, n-dodecyl ((meth)acrylate) (lauryl (meth)acrylate) is preferred, and n-dodecyl (lauryl acrylate) is particularly preferred.

[0075] When the adhesive composition P contains an acrylic monomer (C11), the content of the acrylic monomer (C11) is preferably 5 to 40% by mass, and particularly preferably 8 to 35% by mass, based on the total mass of the adhesive composition P. This allows for a smoother application and formation of the adhesive layer when the (meth)acrylic acid ester polymer (A) is solvent-free.

[0076] (1-7) Various additives The adhesive composition P may optionally contain various additives commonly used in acrylic adhesives, such as silane coupling agents, ultraviolet absorbers, infrared absorbers, refractive index modifiers, antistatic agents, colorants, tackifiers, rust inhibitors, antioxidants, light stabilizers, and softeners.

[0077] (2) Preparation of adhesive composition The adhesive composition P can be prepared, for example, by producing a (meth)acrylic acid ester polymer (A1) and mixing the obtained (meth)acrylic acid ester polymer (A1) with other components.

[0078] (Meth)acrylic acid ester polymer (A1) can be produced by polymerizing a mixture of monomers constituting the polymer using a conventional radical polymerization method.

[0079] Once the (meth)acrylic acid ester polymer (A1) is obtained, a crosslinking agent (B), an active energy ray curable component (C), a photopolymerization initiator (D), additives, a diluent, etc., are optionally added to the solution of the (meth)acrylic acid ester polymer (A1), and the mixture is thoroughly mixed to obtain a solvent-diluted adhesive composition P (coating solution). If any of the above components are used in solid form, or if precipitation occurs when mixed with other components in an undiluted state, that component may be dissolved or diluted in a diluent beforehand before mixing with the other components.

[0080] The adhesive composition P may contain the above-mentioned active energy ray-curable monomer (C1) instead of the diluent. This makes it easy to impart fluidity to the adhesive composition P and adjust its viscosity without using a diluent.

[0081] 1-2-2.Thermoplastic resin layer The case where the adhesive layer 20 is a thermoplastic resin layer made of a thermoplastic resin will be described below.

[0082] The thermoplastic resin constituting the thermoplastic resin layer is not particularly limited, as long as it can securely fix the analytical cover film 1 and the analytical substrate 2 by heat fusion and does not adversely affect the analysis.

[0083] Specific examples of the thermoplastic resins mentioned above include polyolefin resins, polyester resins, polyurethane resins, polyester urethane resins, acrylic resins, amide resins, styrene resins, silane resins, and rubber resins. Polyolefin resins may be modified, for example, acid-modified polyolefin resins and silane-modified polyolefin resins. These can be used individually or in combination of two or more types.

[0084] Among the specific examples of thermoplastic resins described above, polyolefin resins, polyester resins, or acrylic resins are preferred, with polyester resins being particularly preferred, from the viewpoint of exhibiting good adhesion and being less likely to adversely affect analysis using the analytical cover film 1.

[0085] The glass transition temperature (Tg) of the thermoplastic resin constituting the thermoplastic resin layer is preferably 35°C or higher, particularly preferably 40°C or higher, and even more preferably 45°C or higher. This makes it difficult for the thermoplastic resin layer to melt even if the analytical member 100 is heated during analysis, effectively suppressing peeling and displacement at the interface between the thermoplastic resin layer and the base film 10 or analytical substrate 2. Furthermore, the glass transition temperature (Tg) is preferably 150°C or lower, particularly preferably 145°C or lower, and even more preferably 140°C or lower. This eliminates the need for excessive heating when fixing the analytical cover film 1 and the analytical substrate 2 by heat fusion of the thermoplastic resin layer for the manufacture of the analytical member 100, preventing deformation of other components and reducing manufacturing costs.

[0086] 2. Method for manufacturing analytical cover film (1) When using the heat-crosslinkable adhesive composition P When using a heat-crosslinkable adhesive composition P to form the adhesive layer 20 (adhesive layer), it is preferable to apply the adhesive composition P coating solution to the release surface of the release sheet and perform a heat treatment to thermally crosslink the adhesive composition P, and if necessary, allow for a curing period. This forms the adhesive layer 20 (adhesive layer).

[0087] Thermal crosslinking of the adhesive composition P can be performed by heat treatment. This heat treatment can also be combined with the drying treatment after application of the adhesive composition P. The heating temperature for the heat treatment is preferably 50 to 150°C, and particularly preferably 70 to 120°C. The heating time is preferably 10 seconds to 10 minutes, and particularly preferably 50 seconds to 2 minutes. After the heat treatment, a curing period of 1 to 2 weeks at room temperature (e.g., 23°C, 50% RH) may be provided as needed. If a curing period is necessary, the adhesive will be formed after the curing period has elapsed; if a curing period is not necessary, the adhesive will be formed after the heat treatment is completed.

[0088] The above heat treatment (and curing) forms a crosslinked product of the (meth)acrylic acid ester polymer (A) crosslinked with the crosslinking agent (B).

[0089] In this specification, the term "peel surface" of a release sheet refers to the surface of the release sheet that exhibits peelability, and includes both surfaces that have undergone a peeling treatment and surfaces that exhibit peelability even without a peeling treatment.

[0090] Methods for applying the coating solution of the above-mentioned adhesive composition P include, for example, bar coating, knife coating, roll coating, blade coating, die coating, etc.

[0091] Examples of release sheets include polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, vinyl chloride copolymer film, polyethylene terephthalate film, polyethylene naphthalate film, polybutylene terephthalate film, polyurethane film, ethylene vinyl acetate film, ionomer resin film, ethylene-(meth)acrylic acid copolymer film, ethylene-(meth)acrylic acid ester polymer film, polystyrene film, polycarbonate film, polyimide film, fluororesin film, etc. Crosslinked films of these materials are also used. Furthermore, laminated films of these materials may also be used.

[0092] It is preferable that the release surface (the surface in contact with the adhesive layer 20) of the above-mentioned release sheet be subjected to a release treatment. Examples of release agents used for the release treatment include alkyd, silicone, fluorine, unsaturated polyester, polyolefin, and wax-based release agents.

[0093] As described above, when the adhesive composition P is applied to the release surface of the release sheet, the arithmetic mean roughness Ra of the release surface of the release sheet (the surface in contact with the adhesive layer 20) is preferably 100 nm or less, more preferably 50 nm or less, and particularly preferably 15 nm or less. This allows the surface shape of the release surface to be transferred to the side of the adhesive layer 20 that is attached to the analytical substrate 2 (the adhesive surface), resulting in a smooth adhesive surface of the adhesive layer 20, which makes it easier for the adhesive surface of the adhesive layer 20 to satisfy the aforementioned arithmetic mean roughness Ra. The lower limit of the arithmetic mean roughness Ra is not particularly limited, but is usually preferably 0.5 nm or more, and particularly preferably 1 nm or more. The method for measuring the arithmetic mean roughness Ra of the release surface of the release sheet in this specification is as shown in the test examples described later.

[0094] As described above, once the adhesive layer 20 is formed on the release surface of the release sheet, the adhesive layer 20 on the release sheet and the base film 10 are bonded together to obtain the analytical cover film 1. The release sheet protects the adhesive layer 20 until the analytical cover film 1 is used, and is peeled off when the analytical cover film 1 is used.

[0095] (2) When using an active energy ray curable adhesive composition P When using an active energy ray-curable adhesive composition P to form the adhesive layer 20 (adhesive layer), it is preferable to directly apply the coating solution of the adhesive composition P to one side of the base film 10, and then irradiate it with active energy rays to cure the coating layer of the adhesive composition P. This forms an adhesive layer 20 (adhesive layer) on one side of the base film 10, and an analytical cover film 1 is obtained. In this case, the side of the adhesive layer opposite to the side facing the base film 10 becomes the adhesive surface. With this manufacturing method, the adhesive layer is less likely to get embedded in the grooves 4 of the analytical substrate 2, and it is easier to obtain an adhesive layer with high cohesiveness.

[0096] Active energy rays refer to electromagnetic waves or charged particle beams that possess energy quanta, specifically including ultraviolet rays and electron beams. Among active energy rays, ultraviolet rays are particularly preferred because they are easy to handle.

[0097] Ultraviolet irradiation can be performed using high-pressure mercury lamps, Heraeus H lamps, xenon lamps, etc., with an illuminance of 50-1000 mW / cm². 2 It is preferable that the light intensity be around 50 to 10,000 mJ / cm². 2 Preferably, it is 80-5000 mJ / cm². 2 It is more preferable that the concentration be 300-2000 mJ / cm². 2 It is particularly preferable that this is the case. On the other hand, electron beam irradiation can be performed by an electron beam accelerator or the like, and the electron beam irradiation dose is preferably about 10 to 1000 krad.

[0098] In addition to the above-described coating method, known printing methods can be used to apply the coating liquid of the adhesive composition P. Examples include screen printing, gravure printing, offset printing, and inkjet printing. Among these, screen printing is preferred because it is easy to control the arithmetic mean roughness Ra of the adhesive surface of the resulting adhesive layer 20 to the aforementioned range by appropriately lowering the viscosity of the coating liquid of the adhesive composition P.

[0099] The analytical cover film 1, which has an adhesive layer formed on a base film 10, is usually stored with a release sheet attached to the adhesive layer, or it is bonded in-line to the analytical substrate 2 after the adhesive layer is formed. When the adhesive layer is irradiated with active energy rays before bonding with other components such as the release sheet or the analytical substrate 2, the surface shape of the adhesive surface immediately before irradiation with active energy rays after the application of the adhesive composition P is easily maintained. Therefore, the surface shape of the adhesive surface is influenced by the application conditions of the adhesive composition P, and the lower the viscosity of the adhesive composition P, the more smooth the surface shape of the adhesive surface tends to be.

[0100] Furthermore, similar to the case where a thermally crosslinkable adhesive composition P is used, an active energy ray-curable adhesive composition P can be applied to a release sheet, and the formed coating layer can be bonded to the base film 10. In this case, it is preferable to cure the coating layer by active energy ray irradiation before bonding it to the analytical substrate 2 to form an adhesive layer 20 (adhesive layer). It is preferable to use the same release sheet as when using a thermally crosslinkable adhesive composition P.

[0101] (3) When using thermoplastic resin When using a thermoplastic resin to form the adhesive layer 20 (thermoplastic resin layer), it is preferable to directly form the thermoplastic resin layer on one side of the base film 10. For example, methods include applying a coating solution containing the materials for the adhesive layer 20 and a diluent solvent onto one side of the base film 10 and drying it to form the thermoplastic resin layer; extruding and laminating the materials for the thermoplastic resin layer onto one side of the base film 10; and co-extruding the materials for the base film 10 and the materials for the thermoplastic resin layer. The diluent solvent can be the same as that used in the adhesive composition P.

[0102] An example of a method for forming a thermoplastic resin layer by applying a coating solution containing materials for forming a thermoplastic resin layer onto one side of a base film 10 and drying it is to prepare a coating solution containing materials for forming the thermoplastic resin layer and optionally a solvent or dispersion medium, apply the coating solution onto one side of the base film 10 using a casting method such as a bar coater, die coater, curtain coater, slit coater, or knife coater to form a coating film, and then dry the coating film. A spray coater or the like may also be used as the coating means.

[0103] An example of a method for extruding and laminating a thermoplastic resin layer onto a base film 10 is to use a T-die film-making machine or the like to melt and knead the material for constituting the thermoplastic resin layer, and then extrude and laminate the molten material onto one side of the base film 10 while moving the base film 10 at a constant speed, thereby obtaining an analytical cover film 1. The temperature at which the material constituting the thermoplastic resin layer is melted is preferably such that the base film 10 does not deform due to the temperature (heat) of the molten material, for example, preferably 120 to 300°C, and particularly preferably 150 to 250°C.

[0104] 3. Characteristics of the analytical cover film and adhesive layer (1) Thickness of the adhesive layer The thickness of the adhesive layer is preferably 0.3 μm or more, more preferably 0.6 μm or more, particularly preferably 0.8 μm or more, and even more preferably 1 μm or more. This makes it possible to fix the analytical cover film 1 to the analytical substrate 2 well. Furthermore, the above thickness is preferably 500 μm or less, more preferably 30 μm or less, particularly preferably 20 μm or less, and even more preferably 15 μm or less. This reduces the influence of the thickness of the adhesive layer 20 on the analysis, making it easier to perform good analysis on the resulting analytical member 100. For example, when irradiating an analyte in the groove 4 with laser light and analyzing scattered light and fluorescence, it becomes easier to focus the laser on the analyte, and the laser beam spot can be miniaturized, enabling analysis of a minute area.

[0105] Here, when using laser light with a wavelength of 450 nm or less as analytical light, the thickness of the adhesive layer 20 is preferably 15 μm or less, particularly preferably 13 μm or less, and even more preferably 11 μm or less, taking into consideration the transmittance of the laser light. If the thickness of the adhesive layer 20 is greater than 15 μm, after the analytical cover film 1 is attached to the analytical substrate 2, the strain caused by coarse protrusions on the adhesive surface of the adhesive layer 20 is more easily relieved within the adhesive layer 20. However, if the thickness of the adhesive layer 20 is 15 μm or less, it is necessary to control the reduction of coarse protrusions on the adhesive surface of the adhesive layer 20 in order to prevent such strain from occurring. For this reason, in this embodiment, the arithmetic mean roughness Ra of the adhesive surface of the adhesive layer 20 is set to 500 nm or less.

[0106] Furthermore, if the adhesive layer 20 is a thermoplastic resin layer, the thickness of the thermoplastic resin layer is preferably greater than 4 μm, and more preferably 5 μm or more. This makes it possible to improve the adhesion of the thermoplastic resin layer to the analytical substrate 2. On the other hand, when the analytical cover film 1 is attached to the analytical substrate 2, the thermoplastic resin layer is more likely to penetrate the grooves 4 of the analytical substrate 2 than when the thermoplastic resin layer is thinner (for example, 1 μm). However, in this embodiment, because the arithmetic mean roughness Ra of the adhesive surface of the adhesive layer 20 (thermoplastic resin layer) is small, attachment can be performed under mild conditions in which the thermoplastic resin layer is less likely to penetrate the grooves 4, and even then, fluid seepage from the grooves 4 is less likely to occur.

[0107] (2) Transmittance of analytical light When analytical light is used for analysis, the transmittance of the analytical light in the analytical cover film 1 is preferably 60% or higher, particularly preferably 80% or higher, and even more preferably 90% or higher. This allows the analytical cover film 1 to have better transmittance to the analytical light. As a result, it becomes possible to perform more accurate analysis with the analytical component 100 using the analytical cover film 1. The upper limit of the above transmittance is not particularly limited, but is 100% or less.

[0108] (3) Thickness of the cover film for analysis In this embodiment, the thickness of the analytical cover film 1 is preferably 10 μm or more, particularly preferably 30 μm or more, and even more preferably 75 μm or more. This ensures that the analytical cover film 1 has sufficient strength, is easy to handle, and suppresses deformation and damage to the analytical cover film 1 when using the analytical member 100. When laser light is used for analysis, a thickness of 75 μm or more in the analytical cover film 1 makes it easier to focus on the analyte in the flow path. Furthermore, the above thickness is preferably 300 μm or less, particularly preferably 250 μm or less, and even more preferably 200 μm or less. This makes it easier for the analytical cover film 1 to have excellent transmittance to analytical light, and facilitates good analysis of the resulting analytical member 100. Note that the thickness of the analytical cover film is the thickness excluding the release sheet if a release sheet is laminated to the analytical cover film.

[0109] [Analytical components] Figure 2 shows a cross-sectional view of the analysis member 100 according to this embodiment. The analysis member 100 comprises an analysis substrate 2 and the analysis cover film 1 described above, which is attached to the analysis substrate 2. The analysis substrate 2 has a groove 4 as a housing portion for housing the object to be analyzed, and a planar adhesive attachment portion 3 adjacent to the groove 4. The analysis cover film 1 is attached to the analysis substrate 2 by the adhesive layer 20 of the analysis cover film 1 being attached to the adhesive attachment portion 3. The groove 4 of the analysis substrate 2 has its opening (the upper surface of the groove 4 in Figure 2) sealed by the analysis cover film 1, thereby forming a flow path. In this analysis member 100, analysis is performed on the object to be analyzed housed in the groove 4 (flow path). In this embodiment, optical analysis will be mainly described as the analysis method, but the present invention is not limited thereto.

[0110] In the analytical member 100 according to this embodiment, the arithmetic mean roughness Ra of the side of the adhesive layer 20 of the analytical cover film 1 that is attached to the analytical substrate 2 (adhesive surface) is 500 nm or less (before attachment), so that it adheres closely to the planar adhesive attachment portion 3 adjacent to the groove 4 of the analytical substrate 2. Therefore, gaps are less likely to occur between the adhesive layer 20 and the adhesive attachment portion 3 at the boundary between the groove 4 and the adhesive attachment portion 3, and thus, the leakage of fluid contained in the groove 4 between the adhesive layer 20 and the adhesive attachment portion 3 is effectively suppressed.

[0111] The shape of the analysis member 100 in plan view according to this embodiment is not particularly limited, but it is preferably disc-shaped or chip-shaped. Disc-shaped means that the shape of the analysis member 100 in plan view is a perfect circle or a deformed shape thereof. If it is disc-shaped, a hole may be provided in the center of the analysis member 100, and the shape of the hole may be a circular shape that is concentric with the outer circumference of the analysis member 100 in plan view. Chip-shaped means that the shape of the analysis member 100 in plan view is a square, a rectangle, or a deformed shape thereof.

[0112] 1. Components of the analytical material (1) Cover film for analysis The analytical cover film 1 in this embodiment is the one described in the previously mentioned embodiment.

[0113] (2) Analysis base material In the analytical member 100 according to this embodiment, the analytical substrate 2 is not particularly limited as long as it is possible to perform analysis using the analytical member 100 equipped with the analytical substrate 2. When performing optical analysis, it is preferable that the analytical substrate 2 is transparent to analytical light from the viewpoint of enabling good analysis. The shape of the analytical substrate 2 is preferably plate-shaped, but is not limited thereto.

[0114] The material for the analytical substrate 2 can be resin, glass, etc., but it is preferable to use resin from the viewpoint of ease of manufacture and handling. The resin can be the same as the resin that makes up the resin film that can be used as the base film 10. Among such resins, it is preferable to use polycarbonate, cycloolefin copolymer, polyethylene terephthalate film, or acrylic resin from the viewpoint of excellent transmittance to analytical light and excellent moldability, and in particular, it is preferable to use cycloolefin copolymer or polycarbonate. Furthermore, as mentioned above, from the viewpoint of minimizing the difference in transmittance to analytical light, it is preferable to use the same material for the analytical substrate 2 as the material for the base film 10.

[0115] The glass transition temperature (Tg) of the material constituting the analytical substrate 2 is preferably 100°C or higher, particularly preferably 120°C or higher, and even more preferably 140°C or higher. A glass transition temperature (Tg) of 100°C or higher makes it difficult for the analytical substrate 2 to melt even if the analytical member 100 is heated during analysis, effectively suppressing deformation of the analytical substrate 2 and effectively preventing peeling or displacement at the interface between the adhesive layer 20 and the analytical substrate 2. While there are no particular upper limits on the glass transition temperature (Tg) of the material constituting the analytical substrate 2, it is generally preferably 300°C or lower, particularly preferably 250°C or lower, and even more preferably 200°C or lower.

[0116] When performing optical analysis, the transmittance of the analytical light in the analytical substrate 2 is preferably 60% or higher, particularly preferably 80% or higher, and even more preferably 90% or higher. A transmittance of 60% or higher allows the analytical component 100 to have better transmittance to the analytical light, enabling more accurate analysis. The upper limit of the above transmittance is not particularly limited, but is 100% or less.

[0117] When performing optical analysis, the haze value of the analytical substrate 2 is preferably 10% or less, particularly preferably 5% or less, and even more preferably 1% or less. By having a haze value of 10% or less of the analytical substrate 2, the scattering of analytical light on the analytical substrate 2 can be effectively reduced, making it possible to perform more accurate analysis on the analytical component 100. Although there is no particular limit to the lower limit of the haze value of the analytical substrate 2, it is usually 0% or higher.

[0118] In this embodiment, it is preferable that the analytical substrate 2 has at least one groove 4 on one side thereof. Here, in the analytical substrate 2 of the analytical member 100 shown in Figure 2, multiple grooves 4 with a width w1 and a depth d1 (three in Figure 2) are provided on the side of the analytical substrate 2 facing the adhesive layer 20.

[0119] The cross-sectional shape of groove 4 is not limited as long as it can accommodate the analyte and allow for good analysis. In Figure 2, the shape of the cross-section is triangular, but it is not limited to this and may be square, rectangular, semicircular, etc.

[0120] The shape of the groove 4 in plan view is not limited as long as it can accommodate the analyte and allow for good analysis; for example, it may be linear, dotted, etc. However, from the viewpoint of allowing the analytical light to be scanned along the groove 4, a linear shape is preferable.

[0121] The various dimensions of the groove 4 can be set according to the analysis method and the type of analyte being analyzed. For example, the width w1 of the groove 4 is preferably 50 nm or more, particularly preferably 100 nm or more, and even more preferably 150 nm or more. Furthermore, the width w1 is preferably 30 μm or less, particularly preferably 10 μm or less, and even more preferably 1 μm or less. The depth d1 of the groove 4 is preferably 50 nm or more, particularly preferably 100 nm or more, and even more preferably 150 nm or more. Furthermore, the depth d1 is preferably 30 μm or less, particularly preferably 10 μm or less, and even more preferably 1 μm or less. By having the width w1 and depth d1 of the groove 4 within the above ranges, it is possible to suppress the amount of analyte required while ensuring a sufficient length for the analytical light to pass through the analyte.

[0122] The thickness of the analytical substrate 2 (the distance between the surface to which the adhesive layer 20 is attached and the opposite surface) is preferably 0.5 mm or more, particularly preferably 0.8 mm or more, and even more preferably 1 mm or more. This ensures that the analytical substrate 2 has sufficient strength, effectively suppressing deformation of the analytical member 100 when containing the analyte and during analysis. Furthermore, the thickness is preferably 10 mm or less, particularly preferably 5 mm or less, and even more preferably 3 mm or less. This allows the analytical light to reach the analyte more easily during analysis, facilitating high-precision analysis.

[0123] The method for manufacturing the analytical substrate 2 is not particularly limited. However, if the analytical substrate 2 is made of resin, it is preferable to manufacture it by molding it by injection molding, compression molding, insert molding, etc., and applying surface treatment as necessary.

[0124] (3) Others The analytical member 100 according to this embodiment may have a hole for receiving the object to be analyzed in the groove 4. The receiving hole may be provided in at least one of the analytical cover film 1 and the analytical substrate 2, but it is particularly preferable to provide it in the analytical cover film 1. The shape and size of the receiving hole are preferably suitable for the receiving means used to house the object to be analyzed in the groove 4. Furthermore, if the analytical member 100 according to this embodiment has the above-mentioned receiving hole, it is also preferable to have an air vent hole.

[0125] The containment section for the analyte has openings on both the front and back of the analysis substrate 2, and may also be a slit that penetrates both sides. In this case, both the front and back surfaces of the analysis substrate 2 function as adhesive application areas 3, and by attaching the analysis cover film 1 to both surfaces, the slit sandwiched between the analysis cover film 1 functions as a flow path.

[0126] 2. Method for manufacturing analytical components (1) When the adhesive layer 20 is a tack layer When the adhesive layer 20 is an adhesive layer, to manufacture the analytical member 100 according to this embodiment, the analytical cover film 1 should be attached to the analytical substrate 2 so that the adhesive layer 20 of the analytical cover film 1 is attached to the adhesive attachment portion 3 of the analytical substrate 2. If a release sheet is laminated on the adhesive layer 20 of the analytical cover film 1, the release sheet should be peeled off to expose the adhesive layer 20 before the above attachment is performed. In this way, the opening of the housing portion is sealed by the analytical cover film 1, and the analytical member 100 with a flow channel can be manufactured very easily.

[0127] (2) When the adhesive layer 20 is a thermoplastic resin layer When the adhesive layer 20 is a thermoplastic resin layer, the analytical member 100 according to this embodiment is manufactured by heat-sealing the adhesive layer 20 to bond the adhesive-side surface of the analytical cover film 1 to the adhesive-bonded portion 3 of the analytical substrate 2.

[0128] In particular, the manufacturing method of the analytical member 100 preferably includes a step of heat-sealing the adhesive-bonded portion 3 of the analytical substrate 2 and the surface of the analytical cover film 1 on the adhesive layer 20 side, so that the groove 4 is not filled by the adhesive layer 20, thereby bonding the analytical substrate 2 and the analytical cover film 1. In this case, the specific method is not limited as long as the adhesive layer 20, which is in a heated and molten state, can be laminated onto the analytical substrate 2, and can be carried out, for example, by thermocompression bonding.

[0129] The heat-sealing process can be performed using, for example, a heating press or heating roller. The heating temperature is preferably 60 to 170°C, and more preferably 70 to 150°C. The heat-sealing pressure is preferably 0.1 to 10 MPa, and more preferably 0.5 to 3 MPa. When using a heating press, the heat-sealing time is preferably 1 to 20 minutes, and more preferably 5 to 15 minutes. When using heating rollers, the conveying speed is preferably 0.1 to 5 m / min, and more preferably 0.5 to 1 m / min. By performing the heat-sealing process under these conditions, the intrusion of the thermoplastic resin into the grooves 4 can be effectively suppressed, and the analytical cover film 1 and the analytical substrate 2 can be well fixed together.

[0130] 3. How to use the analytical material The analytical member 100 according to this embodiment can be used, for example, for the optical analysis of an analyte. Specifically, after placing the analyte in the flow path of the analytical member 100, light is irradiated onto the placed analyte from outside the analytical member 100, and the resulting light (including transmitted light, scattered light, and fluorescence) is measured outside the analytical member 100.

[0131] The primary material to be analyzed is a specimen, but it is not limited to this. A specimen typically refers to material used for medical testing and analysis, such as blood, cerebrospinal fluid, urine, tissue, or cells, which are excreted or collected from the human body.

[0132] The analyte in this embodiment is a fluid, and examples include liquids, sol-like components, gel-like components, etc., but a liquid is particularly preferred. The liquid may also contain solid components. Specific examples of the analyte include water or extracts used in water quality or soil analysis, cell extracts, blood, cultured cell fluid, bacteria, archaea, viruses, proteins, algae, microorganisms, etc.

[0133] The analyte can be introduced into the flow path by, for example, supplying it to the flow path through a receiving hole provided in the analytical member 100 using the aforementioned introduction means. Alternatively, a syringe equipped with a needle may be used to insert the needle into a predetermined position in the analytical member 100, and then supply the analyte to the flow path through the needle.

[0134] The irradiation of the contained analyte with analytical light and subsequent measurements are selected according to the purpose of the analysis. Examples include absorbance measurement, Raman spectroscopy, and fluorescence analysis.

[0135] The type of analytical light can be selected according to the purpose of the analysis. For example, visible light, ultraviolet light, or laser light can be used.

[0136] When using the analytical member 100, the analytical member 100 may be cooled or heated depending on the analyte used and the analysis performed. However, when heating the analytical member 100, from the viewpoint of suppressing thermal deformation of the adhesive layer 20, it is preferable to use an adhesive layer instead of a thermoplastic resin layer as the adhesive layer, and more preferably to use an adhesive layer formed from an adhesive composition P containing an active energy ray curable component (C).

[0137] The analytical member 100 according to this embodiment can be used not only for optical analysis, but also for analysis and separation of substances by methods such as polymerase chain reaction (PCR) and electrophoresis.

[0138] The embodiments described above are provided to facilitate understanding of the present invention and are not intended to limit it. Accordingly, each element disclosed in the above embodiments is intended to include all design modifications and equivalents that fall within the technical scope of the present invention.

[0139] For example, the adhesive layer 20 of the analytical cover film 1 may be laminated only on a portion of one side of the base film 10, as long as it can be bonded to the analytical substrate 2 and the leakage of fluid contained in the groove 4 is suppressed. [Examples]

[0140] The present invention will be described in more detail below with reference to examples, but the scope of the present invention is not limited to these examples.

[0141] [Manufacturing Example 1] (Preparation of analytical substrate) An analytical substrate (see Analytical Substrate 2 in Figure 2) with three grooves on one side was formed by injection molding of polycarbonate resin (manufactured by Teijin, product name "Panlite AD-5503", Tg: 145℃). The analytical substrate has a disc shape with a diameter of 12 cm and a thickness of 1.2 mm, and a circular hole with a diameter of 1.5 cm is provided in the center of the substrate in a plan view, concentric with the outer circumference. The three grooves are provided at 0.25 mm intervals concentrically with the outer circumference of the analytical substrate in a plan view, and each has a width w1 of 200 nm and a depth d1 of 200 nm. The distance between the groove closest to the outer circumference of the analytical substrate and the outer circumference of the analytical substrate is 2 cm. The arithmetic mean roughness Ra of the surface of the analytical substrate opposite to the surface with grooves was measured to be 120 nm, the transmittance of analytical light (wavelength: 0.63 μm) was 92%, and the haze value was 0.1%.

[0142] [Preparation Example 1] (Preparation of coating solution (A1) of an active energy ray-curable adhesive composition) A coating solution (A1) of an active energy ray-curable adhesive composition was prepared by mixing 100 parts by mass of a UV-curable pressure-sensitive adhesive (manufactured by Jujo Chemical Co., Ltd., product name "JELCON RAYTACK-10N") containing an active energy ray-curable component and a photopolymerization initiator with 15 parts by mass of n-dodecyl acrylate (lauryl acrylate).

[0143] [Preparation Example 2] (Preparation of coating solution (A2) of an active energy ray-curable adhesive composition) A coating solution (A2) of an active energy ray-curable adhesive composition was prepared by mixing 100 parts by mass of a UV-curable pressure-sensitive adhesive (manufactured by Jujo Chemical Co., Ltd., product name "JELCON RAYTACK-10N") containing an active energy ray-curable component and a photopolymerization initiator with 30 parts by mass of n-dodecyl acrylate (lauryl acrylate).

[0144] [Preparation Example 3] (Preparation of thermoplastic resin coating solution (A3)) A thermoplastic resin coating solution (A3) with a solid content of approximately 15% by mass was prepared by mixing 100 parts by mass of polyester resin (manufactured by Toyobo Co., Ltd., product name "Byron 200", number average molecular weight: 17000, Tg: 56℃), methyl ethyl ketone, and toluene.

[0145] [Preparation Example 4] (Preparation of coating solution (A4) for a thermally crosslinkable adhesive composition) A (meth)acrylic acid ester polymer was prepared by copolymerizing 95.8 parts by mass of n-butyl acrylate, 4 parts by mass of acrylic acid, and 0.2 parts by mass of 2-hydroxyethyl acrylate using a solution polymerization method. The molecular weight of this acrylic acid ester copolymer was measured by the method described later, and the weight-average molecular weight (Mw) was found to be 1 million.

[0146] A coating solution (A4) of a thermally crosslinkable adhesive composition was prepared by mixing 100 parts by mass (on a solid content basis; the same applies in this example) of the above (meth)acrylic acid ester polymer, 0.2 parts by mass of trimethylolpropane-modified tolylene diisocyanate as a crosslinking agent (isocyanate type), 0.02 parts by mass of 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane as a crosslinking agent (epoxy type), and 0.1 parts by mass of 3-glycidoxypropyltrimethoxysilane as a silane coupling agent, stirring thoroughly, and diluting with methyl ethyl ketone.

[0147] Here, the weight-average molecular weight (Mw) mentioned above is the weight-average molecular weight in polystyrene terms, measured using gel permeation chromatography (GPC) under the following conditions (GPC measurement). <Measurement conditions> • GPC measuring device: Tosoh Corporation, HLC-8020 • GPC column (passes through in the following order): Manufactured by Tosoh Corporation TSK Guard Column HXL-H TSK gel GMHXL (x2) TSK gel G2000HXL • Measurement solvent: tetrahydrofuran ·Measurement temperature: 40℃

[0148] [Preparation Example 5] (Preparation of an active energy ray-curable adhesive composition (A5)) A UV-curable pressure-sensitive adhesive (manufactured by Jujo Chemical Co., Ltd., product name "JELCON RAYTACK-10N") containing an active energy ray-curable component and a photopolymerization initiator was used as the coating solution (A5) for the active energy ray-curable adhesive composition.

[0149] [Example 1] A polyethylene terephthalate film (S1; manufactured by Toyobo Co., Ltd., product name "Cosmoshine A4360", thickness: 100 μm) was screen printed onto one side of the base film using a coating solution (A1) of the active energy ray-curable adhesive composition prepared in Preparation Example 1.

[0150] Then, the coating on the base film was irradiated with active energy rays (ultraviolet light; UV) to harden the coating and form a 10 μm thick adhesive layer, which was used as the cover film for analysis. The irradiation conditions for the active energy rays were as follows:

[0151] <Activated energy ray irradiation conditions> • UV irradiation device: Manufactured by GS Yuasa Corporation, product name "Nitrogen Purge Small Conveyor Type UV Irradiation Device CSN2-40" • Light source: High-pressure mercury lamp Lamp power: 1.4kW Conveyor speed: 1.2 m / min ·Illuminance: 100mW / cm 2 ·Light amount: 480mJ / cm 2

[0152] Next, the grooved surface of the analytical substrate prepared in Manufacturing Example 1 was bonded to the adhesive layer of the analytical cover film to obtain an analytical member.

[0153] [Example 2] The analytical cover film and analytical member were manufactured in the same manner as in Example 1, except that the coating solution (A2) of the active energy ray-curable adhesive composition prepared in Preparation Example 2 was used instead of the coating solution (A1) of the active energy ray-curable adhesive composition.

[0154] [Example 3] A cycloolefin copolymer film (manufactured by Zeon Corporation, product name "Zeonor ZF16-100", thickness: 100 μm) was used as the base film (S2).

[0155] The thermoplastic resin coating solution (A3) prepared in Preparation Example 3 was applied to the above-mentioned base film using a wire bar. The resulting coating film was heated and dried at 70°C for 1 minute to obtain an analytical cover film in which a thermoplastic resin layer with a thickness of 5 μm was laminated on one side of the base film.

[0156] Next, the grooved surface of the analytical substrate prepared in Manufacturing Example 1 and the thermoplastic resin layer side of the analytical cover film were heat-pressed together using a heating press at a heating temperature of 140°C and a pressure of 1 MPa for 10 minutes to bond them together and obtain an analytical component.

[0157] [Example 4] A release sheet (Lintec Corporation, product name "SP-PLZ38 3030", arithmetic mean roughness Ra: 10.8 nm of the release surface) was made by forming a silicone-based release agent layer on one side of a polyethylene terephthalate film with a thickness of 38 μm. The coating solution (A4) of the heat-crosslinkable adhesive composition prepared in Preparation Example 4 was applied to the release surface using a knife coater, and the resulting coating film was dried in a 100°C oven for 1 minute to form an adhesive layer with a thickness of 5 μm.

[0158] Next, the exposed surface of the adhesive layer on the release sheet was bonded to the base film (S2) prepared in Example 3. After curing for one week in an environment of 23°C and 50% relative humidity, an analytical cover film with a release sheet was obtained, in which the base film, adhesive layer (thickness 5 μm), and release sheet were laminated in this order.

[0159] Next, the release sheet was peeled off from the analytical cover film with the release sheet, and the surface of the exposed adhesive layer was adhered to the grooved surface of the analytical substrate prepared in Manufacturing Example 1 to obtain an analytical member.

[0160] [Comparative Example 1] The analytical cover film and analytical member were manufactured in the same manner as in Example 1, except that the coating solution (A5) of the active energy ray-curable adhesive composition prepared in Preparation Example 5 was used instead of the coating solution (A1) of the active energy ray-curable adhesive composition.

[0161] [Test Example 1] (Measurement of surface roughness of release sheet and adhesive layer) The arithmetic mean roughness Ra (nm) was measured on the surface (release surface) of the release sheet used in Example 4, and on the surface (exposed adhesive surface) of the adhesive layer (tack layer / thermoplastic resin layer) of the analytical cover film manufactured in the Examples and Comparative Examples. For this measurement, an optical interference surface shape observation device (Veeco, product name "WYKO-1100") was used, and a 91.2 μm × 119.8 μm area of ​​the surface of the release sheet or adhesive layer was measured in VSI mode at 10x magnification. In Example 4, the release sheet was peeled off from the analytical cover film with the release sheet attached, and the arithmetic mean roughness Ra (nm) of the exposed adhesive layer was measured. The results are shown in Table 1. The results for the arithmetic mean roughness Ra of the release surface of the release sheet are as described above.

[0162] [Test Example 2] (Evaluation of fluid seepage suppression) In the analytical components manufactured in the examples and comparative examples, an injection hole (receiving hole) for injecting fluid and an air vent hole for removing air were made in a portion of the analytical cover film located directly above the groove of the analytical substrate, and the fluid was filled into the flow path from the injection hole using a syringe. As the fluid, a solution of pure water colored with food coloring was used.

[0163] Thirty minutes after fluid filling, the fluid seepage from the flow path to the interface between the analytical substrate and the adhesive surface was visually evaluated, and the fluid seepage suppression performance was assessed according to the following criteria. The results are shown in Table 1. 5: There is absolutely no fluid leakage. 4: A small amount of fluid seepage is occurring in a few places. 3: Fluid seepage is occurring in a small number of locations, and in a quantity that is not insignificant. 2: Fluid seepage is occurring in multiple locations. 1: Fluid seepage is occurring throughout.

[0164] [Table 1]

[0165] As is clear from Table 1, the analytical cover film and analytical member manufactured in the examples were able to suppress fluid seepage from the grooves. [Industrial applicability]

[0166] The analytical cover film, analytical member, and analytical method according to the present invention are suitable for the analysis of trace amounts of analytes. [Explanation of symbols]

[0167] 1…Cover film for analysis 10…Base film 20…Adhesive layer (adhesive layer / thermoplastic resin layer) 100…Analytical component 2…Analysis base material 3… Adhesive application area 4… Groove (storage area)

Claims

1. An analytical cover film to be attached to an analytical substrate having a containment portion for containing a fluid to be analyzed and a planar adhesive application portion adjacent to the containment portion, The system comprises a base film and an adhesive layer laminated on one side of the base film, The arithmetic mean roughness Ra of the side of the adhesive layer that is attached to the analytical substrate is 500 nm or less. An analytical cover film characterized by the following features.

2. The analytical cover film according to claim 1, characterized in that the receiving portion is a groove having an opening.

3. The analytical cover film according to claim 1, characterized in that the adhesive layer is laminated on the base film so as to face the portion containing the analytical substrate and the portion to which the adhesive is applied.

4. The analytical cover film according to claim 1, characterized in that the adhesive layer is an adhesive layer made of a pressure-sensitive adhesive or a thermoplastic resin layer.

5. The adhesive layer is an adhesive layer made of a pressure-sensitive adhesive, The thickness of the adhesive layer is 0.3 μm or more and 500 μm or less. The analytical cover film according to feature 1.

6. The adhesive layer is a thermoplastic resin layer, The thickness of the thermoplastic resin layer is greater than 4 μm and less than or equal to 500 μm. The analytical cover film according to feature 1.

7. The analytical cover film according to claim 1, characterized in that a hard coat layer is formed on the surface of the substrate opposite to the adhesive layer.

8. An analytical substrate having a containment section for containing a fluid to be analyzed, and a planar adhesive application section adjacent to the containment section, An analytical cover film according to any one of claims 1 to 7, attached to the analytical substrate, Equipped with, An analytical member in which a flow path is formed by sealing the opening of the housing portion with the analytical cover film.

9. Prepare the analytical member described in claim 8, The fluid to be analyzed is contained in the flow path of the analytical member, An analytical method for analyzing the substance to be analyzed in the aforementioned flow path.

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