Laminate and laminate manufacturing method

Abstract

This laminate comprises: a first member formed of polystyrene or polycarbonate; a second member formed of a silicone rubber; and an adhesive layer which bonds a first surface of the first member and a second surface of the second member, wherein the adhesive layer is provided on the first surface by using a silane coupling agent having an amino group. Moreover, this laminate manufacturing method comprises: an application step for applying an adhesive, which contains a silane coupling agent having an amino group, onto a first surface of a first member formed of polystyrene or polycarbonate; and a bonding step for bonding the first surface of the first member and a second surface of a second member with the adhesive.

Description

Laminate and method for manufacturing laminate

[0001] The present disclosure relates to laminates and methods for manufacturing laminates.

[0002] A technique for joining two members made of different materials with a silane coupling agent has been known.

[0003] Patent Document 1 discloses a laminate including a first member made of silicone rubber, a second member made of polystyrene, and an adhesive that bonds a first surface of the first member to a second surface of the second member. The adhesive layer includes a first layer formed on the first surface using a silane coupling agent having an epoxy group, and a second layer formed on the second surface using a silane coupling agent having an amino group.

[0004] International Publication No. 2023 / 136157

[0005] The technology of Patent Document 1 uses two types of silane coupling agents, which may complicate the process for manufacturing the laminate. Therefore, there is a need for a laminate that is easy to manufacture and can ensure sufficient durability of the bond between the first member and the second member.

[0006] In order to solve the above problems, a laminate according to one embodiment of the present disclosure comprises a first member made of polystyrene or polycarbonate, a second member made of silicone rubber, and an adhesive layer bonding a first surface of the first member and a second surface of the second member, the adhesive layer being provided on the first surface using a silane coupling agent having an amino group.

[0007] A method for manufacturing a laminate according to one aspect of the present disclosure includes a coating step of applying an adhesive containing a silane coupling agent having an amino group to a first surface of a first member formed of polystyrene or polycarbonate, and a bonding step of bonding the first surface of the first member and the second surface of a second member with the adhesive.

[0008] According to the present disclosure, manufacturing is easier than ever before, and durability of the bond between the first member and the second member can be sufficiently ensured.

[0009] Fig. 2 is a cross-sectional view of a laminate according to an embodiment. Fig. 3 is a plan view of the laminate shown in Fig. 1. Fig. 4 is a flow diagram showing a method for manufacturing a laminate according to an embodiment. Fig. 5 is a diagram showing locations where adhesive layers were provided in Examples. Fig. 6 is a diagram for explaining a 90-degree peel test.

[0010] Preferred embodiments of the present disclosure will be described below with reference to the accompanying drawings. Note that the dimensions or scale of each part in the drawings may differ from the actual dimensions, and some parts are shown schematically to facilitate understanding. Furthermore, the scope of the present disclosure is not limited to the following forms unless otherwise specified in the following description.

[0011] A. Embodiment Fig. 1 is a cross-sectional view of a laminate 100 according to an embodiment. Fig. 2 is a plan view of the laminate 100 shown in Fig. 1. The cross section taken along line A-A in Fig. 2 corresponds to the cross-sectional view in Fig. 1.

[0012] The laminate 100 of this embodiment is used, for example, as a cell culture vessel for culturing various types of cells, more specifically, spheroids. The laminate 100 is suitably used, for example, in fields such as medicine, drug discovery, health care, and animal experiments.

[0013] The laminate 100 shown in Figures 1 and 2 includes a second member 20, a first member 10, and an adhesive layer 30. The first member 10 is made of polystyrene (PS) or polycarbonate. The first member 10 is in the form of a thin plate and has a first surface 15. A plurality of through holes 11 are formed in the first member 10. The plurality of through holes 11 are spaced apart from one another and arranged in a matrix. Each through hole 11 is an opening that penetrates the first member 10.

[0014] The second member 20 is made of silicone rubber. Silicone rubber includes, for example, polydimethylsiloxane (PDMS). Therefore, the second member 20 and the first member 10 are made of different types of materials. The planar shape of the second member 20 is substantially the same as the planar shape of the first member 10. The second member 20 is a thin plate and has a second surface 25. The second surface 25 of the second member 20 and the first surface 15 of the first member 10 face each other. In addition, a plurality of recesses 21 are formed in the second surface 25. The recesses 21 are spaced apart from one another and arranged in a matrix. Each recess 21 is a hemispherical depression with a diameter of, for example, about 1 mm.

[0015] The width of each through-hole 11 in the first member 10 described above is sufficiently larger than the diameter of the opening of the recess 21 in the second member 20. In the example of Fig. 2, 21 recesses 21 correspond to one through-hole 11. Specifically, the 21 recesses 21 overlap one through-hole 11 in plan view. A culture solution or the like is contained in the through-holes 11 and the recesses 21. Cells S to be cultured are also contained in the recesses 21.

[0016] An adhesive layer 30 is interposed between the second member 20 and the first member 10. The adhesive layer 30 is a bonding material for bonding the second surface 25 and the first surface 15. The adhesive layer 30 is formed by an adhesive applied to the second surface 25. The adhesive is formed by a silane coupling agent having an amino group.

[0017] Examples of silane coupling agents having an amino group include N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, and 3-aminopropyltriethoxysilane (APTES). Among these, APTES is preferred.

[0018] As described above, the laminate 100 includes a first member 10 made of polystyrene or polycarbonate, a second member 20 made of silicone rubber, and an adhesive layer 30 that bonds the second surface 25 and the first surface 15 and is formed on the first surface 15 using a silane coupling agent having an amino group. Therefore, in the laminate 100, the second member 20 and the first member 10 are bonded together using a single type of silane coupling agent. Therefore, compared to a configuration in which the second member 20 and the first member 10 are bonded together using two or more types of silane coupling agents, the process for bonding the second member 20 and the first member 10 can be simplified. Therefore, the laminate 100 can be easily manufactured. Furthermore, because the adhesive is formed using a silane coupling agent having an amino group, the durability of the bond between the second member 20 and the first member 10 can be sufficiently ensured, even compared to a configuration in which the adhesive uses two types of silane coupling agents.

[0019] Furthermore, the second member 20, made of silicone rubber, has high oxygen permeability. The second member 20 is provided with multiple recesses 21 in which the cells S to be cultured are placed. The first member 10 has high oxygen permeability, making it particularly suitable for cell culture. Well plates made of a single material, such as polystyrene or polycarbonate, do not have the oxygen permeability necessary for cellular respiration. Therefore, the proliferation potential of cells cultured on such well plates is thought to differ from that in vivo. In contrast, the laminate 100 of this embodiment includes the second member 20 made of silicone rubber, thereby achieving the high proliferation potential of cells achieved by the high oxygen permeability of silicone rubber.

[0020] Furthermore, the first member 10 made of polystyrene or polycarbonate has higher rigidity than the second member 20 made of silicone rubber. Therefore, by providing such a first member 10, the rigidity of the laminate 100 can be increased compared to when the laminate 100 is composed of only the second member 20. This improves the handleability of the laminate 100, i.e., the ease of handling. Therefore, the laminate 100 of this embodiment can achieve both good handleability and high cell proliferation capacity.

[0021] 3 is a flow diagram showing a method for manufacturing the laminate 100 according to the embodiment. As shown in FIG. 3, the method for manufacturing the laminate 100 includes an activation step S1, a preparation step S2, a coating step S3, and a bonding step S4. These steps are performed in this order. However, the preparation step S2 may be performed before the activation step S1 or may be performed in parallel with the activation step S1.

[0022] In the activation step S1, a surface treatment is performed to activate the first surface 15 of the first member 10 by light irradiation. Specifically, the surface treatment in the activation step S1 is a treatment in which excimer light (vacuum ultraviolet light: VUV) or oxygen plasma is irradiated onto each of the first surface 15 and the second surface 25. By performing this surface treatment, hydroxyl groups are exposed on each of the first surface 15 and the second surface 25.

[0023] As described above, in the activation step S1, before the coating step S3, hydroxyl groups are exposed on the first surface 15 by irradiating the first surface 15 with excimer light (VUV) or oxygen plasma.

[0024] In particular, it is preferable to use oxygen plasma in the activation step S1. By using oxygen plasma, hydroxyl groups are easily formed on each of the first surface 15 and the second surface 25, and therefore the subsequent bonding step S4 can be carried out favorably.

[0025] Next, in the preparation step S2, an adhesive containing a silane coupling agent having an amino group is prepared. Specifically, the adhesive is produced by mixing the silane coupling agent with a solvent. The solvent is, for example, water. The silane coupling agent having an amino group is mixed with the solvent at a concentration of 0.1 v / v% or more and 10 v / v or less relative to the solvent to prepare the adhesive. By preparing the silane coupling agent at such a concentration, an adhesive in which the silane coupling agent having an amino group is dissolved or suitably mixed in the solvent is obtained, and the bonding step S4 described below can be suitably performed using this adhesive.

[0026] As mentioned above, the adhesive contains water as a solvent. Silane coupling agents containing amino groups are water-soluble. Therefore, water can be used as a solvent without containing an organic solvent. This eliminates the need to prepare and mix an organic solvent, etc., and thus reduces the complexity of the process. The type of solvent is not limited to water, and may contain an organic solvent such as ethanol.

[0027] Furthermore, the silane coupling agent containing an amino group is particularly preferably aminopropyltriethoxysilane (APTES), which is easier to handle than other coupling agents and can be dissolved or mixed in water alone without containing an organic solvent.

[0028] Next, in the application step S3, an adhesive is applied to the first surface 15 of the first member 10. The adhesive is applied using, for example, a brush, a spray, a roller, or the like. Note that the adhesive may also be applied to the first surface 15 of the first member 10 by immersing the first surface 15 in the adhesive.

[0029] Next, in the joining step S4, the first surface 15 of the first member 10 and the second surface 25 of the second member are joined together. For example, the joining step S4 is started about 5 minutes after the application of the adhesive. The joining step S4 includes a positioning step S41 and a pressure-bonding step S42.

[0030] In the placement step S41, the second member 20 and the first member 10 are placed so that the adhesive on the first surface 15 and the second surface 25 come into contact with each other. In the placement step S41, excess solution is removed by blowing air onto the adhesive on the first surface 15. In the placement step S41, air bubbles between the adhesive and the second surface 25 are removed, thereby allowing the adhesive to adhere sufficiently to the second surface 25 without any gaps.

[0031] In the pressure-bonding step S42, the second member 20 and the first member 10 are pressed against each other at room temperature, thereby bonding the second member 20 and the first member 10 to each other. As described above, the adhesive contains a silane coupling agent containing an amino group, so the second member 20 and the first member 10 can be bonded by applying pressure at room temperature. This eliminates the need for heating, simplifying the process. Note that room temperature is between 5°C and 40°C.

[0032] By the pressure bonding step S42, an adhesive layer 30 containing mainly silicon and oxygen is formed, and the first member 10 and the second member 20 are bonded together.

[0033] As described above, the manufacturing method of the laminate 100 of this embodiment includes a coating step S3 of applying an adhesive containing a silane coupling agent having an amino group to the first surface 15 of the first member 10 formed of polystyrene or polycarbonate, and a bonding step of bonding the first surface 15 of the first member 10 and the second surface 25 of the second member 20 with the adhesive. According to this manufacturing method, the second member 20 and the first member 10 are bonded together using a single type of silane coupling agent. Therefore, compared to a configuration in which the second member 20 and the first member 10 are bonded together using two or more types of silane coupling agents, the process of bonding the second member 20 and the first member 10 can be simplified. Therefore, the laminate 100 can be easily manufactured. Furthermore, because the adhesive is formed using a silane coupling agent having an amino group, the durability of the bond between the second member 20 and the first member 10 can be sufficiently ensured, even compared to a configuration in which the adhesive uses two types of silane coupling agents.

[0034] Examples of the present disclosure will be described below. Note that the following examples are examples of the present disclosure. Therefore, the scope of the present disclosure is not limited to the examples exemplified below.

[0035] 1. First Example [Example] A 110 mm x 74 mm polystyrene well plate was prepared as the first member 10. A 110 mm x 74 mm rectangular PDMS sheet was prepared as the second member 20. An APTES aqueous solution was prepared as the adhesive. The APTES aqueous solution was obtained by preparing a 1 v / v % aqueous solution of 3-aminopropyltriethoxysilane (product name: TCI A0439).

[0036] Next, oxygen plasma was irradiated to each of the well plate as the first member 10 and the PDMS sheet as the second member 20. The irradiation conditions were 100 W and 1 minute.

[0037] Next, the well plate serving as the first member 10 was immersed in an APTES aqueous solution as an adhesive at room temperature for 5 minutes. Next, the well plate serving as the first member 10 was removed from the APTES aqueous solution, and the moisture on the surface was removed. Next, a PDMS sheet serving as the second member 20 was attached to the surface of the well plate serving as the first member 10, and the resultant was left standing at room temperature for 5 minutes.

[0038] Figure 4 shows the location where an adhesive layer was provided in the example. Figure 4(a) is a plan view, and Figure 4(b) is a cross-sectional view. As shown in Figure 4, an adhesive layer 30 is provided in a portion between the first member 10 and the second member 20. By the method described above, a laminate 100 of the example was formed, which includes the first member 10, the second member 20, and the adhesive layer 30 that bonds portions of these members together, as shown in Figure 4.

[0039] Comparative Example: A 110 mm x 74 mm polystyrene well plate was prepared as the first member 10. A 110 mm x 74 mm rectangular PDMS sheet was prepared as the second member 20. The first adhesive was prepared by mixing 3-aminopropyltriethoxysilane as a silane coupling agent with a 90% aqueous ethanol solution to prepare a 1 wt % solution of the silane coupling agent. The product name for this 3-aminopropyltriethoxysilane is TCI A0439. The second adhesive was prepared by mixing 3-glycidyloxypropyltrimethoxysilane as a silane coupling agent with a 90% aqueous ethanol solution to prepare a 1 wt % solution of the silane coupling agent. The product name of this 3-glycidyloxypropyltrimethoxysilane is TCI G0210.

[0040] Next, the well plate serving as the first member 10 and the PDMS sheet serving as the second member 20 were each irradiated with excimer light (VUV). The irradiation conditions were 100 W and 1 minute. Next, the first adhesive was applied to the well plate serving as the first member 10, and the second adhesive was applied to the second member 20. Each was then left to stand for 5 minutes and air-dried. Next, the first member 10 and the second member 20 were bonded together using the first adhesive and the second adhesive, and then left to stand for 10 minutes.

[0041] In the comparative example, similarly to the example shown in FIG. 4, a laminate was formed in which parts of the first member 10 and the second member 20 were bonded together by an adhesive layer.

[0042] [90-degree Peel Test] Figure 4 is a diagram illustrating the 90-degree peel test. As shown in Figure 4, the first member 10 is fixed, and the second member 20 is peeled at a constant speed in the direction indicated by the arrow Ax, perpendicular to the first member 10. The strength measured when the adhesive surface breaks or when the PDMS sheet serving as the second member 20 breaks is defined as the adhesive strength. The results are shown in Table 1.

[0043] Table 1 shows the adhesive strength [N] of each of Examples 1 and 2 and Comparative Examples 1, 2, and 3 of the present disclosure, and whether the adhesive bond peeled off or the PDMS sheet serving as the second member 20 broke.

[0044]

[0045] As shown in Table 1, the adhesive strength of the Examples was not inferior to that of the Comparative Examples. In particular, it was found that the Examples had adhesive strength strong enough to cause the PDMS sheet as the second member to peel off without causing peeling of the adhesive surface.

[0046] As can be seen from the results in Table 1, with the laminate 100 of the example, adhesion using one type of silane coupling agent did not result in inferior adhesive strength compared to when two types of silane coupling agents were used. Furthermore, using one type of adhesive can significantly reduce the manufacturing effort compared to when two types of adhesives are used.

[0047] 2. Second Example An example in which the laminate 100 was used as a cell culture vessel is shown below. [Example] As the first member 10, a well bottomless plate manufactured by WATSON, model number: BTML-96, was prepared.

[0048] An APTES aqueous solution was prepared as an adhesive by preparing a 1 v / v % aqueous solution of 3-aminopropyltriethoxysilane. The product name of this 3-aminopropyltriethoxysilane is TCI A0439.

[0049] Next, oxygen plasma was irradiated to each of the well-bottomless plate as the first member 10 and the PDMS sheet as the second member 20. The irradiation conditions were 100 W and 1 minute.

[0050] Next, the well bottomless plate serving as the first member 10 was immersed in an APTES aqueous solution serving as an adhesive at room temperature for 5 minutes. The PDMS sheet serving as the second member 20 was covered and allowed to stand in a clean bench. The standing time was 10 minutes or less. Next, the well plate serving as the first member 10 was removed from the APTES aqueous solution and dried by removing moisture from the surface. Next, the PDMS sheet serving as the second member 20 was bonded to the surface of the well bottomless plate serving as the first member 10, and a pressure of 1 kN to 1.5 kN was applied for several seconds. This resulted in a laminate 100. The laminate 100 was then allowed to stand at room temperature for 5 minutes.

[0051] [Durability Test by Centrifugation] In the durability test by centrifugation, it was confirmed whether leakage occurred at the adhesive interface due to centrifugation. The centrifugation conditions were 3200 rpm, 400 G, and 5 minutes. To check for leakage during this centrifugation, a uranine fluorescent solution with a concentration of 100 ppm was used to make it easier to check for leakage. After centrifugation, it was confirmed using a fluorescence microscope whether or not there was leakage of the uranine fluorescent solution.

[0052] [Results of each durability test] In the durability test using vacuum drawing, no air bubbles were generated. Furthermore, in the durability test using centrifugation, no leakage of the uranine fluorescent solution was confirmed. From these results, it can be seen that in the second example in which the laminate 100 is used as a cell culture vessel, good adhesive strength can be obtained, similar to the first example.

[0053] B. Modifications Specific modifications that can be added to the above-described embodiments are exemplified below. Two or more embodiments arbitrarily selected from the following examples may be combined as appropriate within the scope of not mutually contradicting each other.

[0054] In the above embodiment, the laminate 100 used for cell culture is exemplified, but the use of the laminate 100 is not limited to the above example. In addition, the shapes or dimensions of the second member 20 and the first member 10 can be changed as desired depending on the use of the laminate 100.

[0055] C. Supplementary Notes The following aspects, for example, can be understood from the above embodiment and modified examples.

[0056] A first aspect of the laminate, which is a preferred example of the present disclosure, comprises a first member made of polystyrene or polycarbonate, a second member made of silicone rubber, and an adhesive layer that bonds a first surface of the first member and a second surface of the second member, and the adhesive layer is provided on the first surface using a silane coupling agent having an amino group.

[0057] According to this first aspect, the second member and the first member are bonded together using one type of silane coupling agent, which simplifies the process of bonding the second member and the first member compared to a configuration in which the second member and the first member are bonded together using two or more types of silane coupling agents. Furthermore, because the adhesive is formed using a silane coupling agent having an amino group, the durability of the bond between the second member and the first member can be sufficiently ensured compared to a configuration in which the adhesive uses two types of silane coupling agents.

[0058] A method for manufacturing a laminate of a first aspect, which is a preferred example of the present disclosure, includes a coating step of applying an adhesive containing a silane coupling agent having an amino group to a first surface of a first member formed of polystyrene or polycarbonate, and a bonding step of bonding the first surface of the first member and the second surface of a second member with the adhesive.

[0059] According to this second aspect, since the second member and the first member are bonded using one type of silane coupling agent, the process for bonding the second member and the first member can be simplified compared to a configuration in which the second member and the first member are bonded using two or more types of silane coupling agents. Furthermore, since the adhesive is formed using a silane coupling agent having an amino group, the durability of the bond between the second member and the first member can be sufficiently ensured, even compared to a configuration in which the adhesive uses two types of silane coupling agents.

[0060] In a third aspect, which is a preferred example of the second aspect, in the method for producing a laminate, the adhesive contains a silane coupling agent having an amino group at a concentration of 0.1 v / v % or more and 10 v / v % or less.

[0061] By preparing the adhesive at such a concentration, an adhesive can be obtained in which the silane coupling agent having an amino group is dissolved or suitably mixed in the solvent, and the adhesive can be used to suitably bond the first member and the second member.

[0062] A fourth aspect, which is a preferred example of the second aspect, further comprises an activation step of irradiating the first surface with excimer light or oxygen plasma before the coating step.

[0063] Hydroxyl groups are easily formed on both the first surface and the second surface, and therefore the first member and the second member can be suitably bonded together.

[0064] In a fifth aspect which is a preferable example of the second aspect, the adhesive contains water as a solvent.

[0065] Silane coupling agents containing amino groups are water-soluble. Therefore, water can be used as a solvent without the need for an organic solvent. This eliminates the need to prepare and mix an organic solvent, etc., and thus reduces the complexity of the process.

[0066] In a sixth aspect which is a suitable example of the second aspect, the silane coupling agent having an amino group is aminopropyltriethoxysilane.

[0067] Aminopropyltriethoxysilane is easier to handle than other coupling agents, and can be dissolved or mixed in a solvent containing only water without an organic solvent.

[0068] In a seventh aspect which is a preferred example of the second aspect, in the joining step, the joining with the adhesive is performed at room temperature.

[0069] The adhesive contains a silane coupling agent containing an amino group, so the second member and the first member can be joined by applying pressure at room temperature, eliminating the need for heating and simplifying the process.

[0070] 100...Laminate, 10...First member, 15...First surface, 20...Second member, 25...Second surface, 30...Adhesive layer.

Claims

1. A laminate comprising: a first member made of polystyrene or polycarbonate; a second member made of silicone rubber; and an adhesive layer bonding a first surface of the first member to a second surface of the second member, wherein the adhesive layer is provided on the first surface using a silane coupling agent having an amino group.

2. A method for manufacturing a laminate, comprising: a coating step of coating a first surface of a first member formed from polystyrene or polycarbonate with an adhesive containing a silane coupling agent having an amino group; and a bonding step of bonding the first surface of the first member and the second surface of a second member with the adhesive.

3. The method for producing a laminate according to claim 2, wherein the adhesive contains the silane coupling agent having an amino group at a concentration of 0.1 v / v % or more and 10 v / v % or less.

4. The method for producing a laminate according to claim 2, further comprising an activation step of irradiating the first surface with excimer light or oxygen plasma before the coating step.

5. The method for producing a laminate according to claim 2, wherein the adhesive contains water as a solvent.

6. The method for producing a laminate according to claim 2, wherein the silane coupling agent having an amino group is aminopropyltriethoxysilane.

7. The method for producing a laminate according to claim 2, wherein in the bonding step, bonding with the adhesive is carried out at room temperature.

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